Istraživanja i projektovanja za privredu - Applied Engineering Science 9(2011)2

CONTENTS

Dr Nenad Šekularac, Dr Jelena Ivanović Šekularac, Mr Jasna Čikić Tovarović FORMATION OF FOLDED CONSTRUCTIONS BY USING CONTEMPORARY 297 - 304 WOODEN TRUSSES Tatjana Mrđenović INTEGRATIVE URBAN DESIGN IN REGENERATION – PRINCIPLES FOR 305 - 316 ACHIEVING SUSTAINABLE PLACES

Darko Kosanović, Mr Suzana Filipović, Dr Nina Obradović, Dr Vladimir Pavlović, Momčilo Ristić 317 - 322 MICROSTRUCTURE EVOLUTION AND SINTERING KINETICS OF ZnO

Mr Dragan Ružić, Dr Ferenc Časnji AGRICULTURAL TRACTOR CAB CHARACTERISTICS RELEVANT 323 - 330 FOR MICROCLIMATIC CONDITIONS

Dr Dragiša Tolmač, Dr Slavica Prvulović, Mr Ljubiša Josimović, Dragana Dimitrijević CONCEPT MODEL AND THE SYSTEM OF SUPPLY AND 331 - 338 MANAGEMENT OF BIOMASS

Dr Dragan Ćoćkalo, Dr Dejan Đordjević, Savina Đurin BUSINESS STRATEGY OF PROVIDING CUSTOMER SATISFACTION 339 - 348 AN EXPLORATORY STUDY IN QM CERTIFIED SERBIAN COMPANIES

EVENTS REVIEW

349

ANNOUNCEMENT OF EVENTS

350

BOOK RECOMMENDATION

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INSTRUCTIONS FOR AUTHORS

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EDITORIAL AND ABSTRACTS IN SERBIAN LANGUAGE

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Institute for research and design in commerce & industry, Belgrade. All rights reserved

Journal of Applied Engineering Science 9(2011)2

IMPRESSUM Naučno-stručni časopis ISTRAŽIVANJA I PROJEKTOVANJA ZA PRIVREDU Journal of APPLIED ENGINEERING SCIENCE The journal publishes original and review articles covering the concept of technical science, energy and environment, industrial engineering, quality management and other realted sciencies. The Journal follows new trends and progress proven practice in listed fields, thus creating a unique forum for interdisciplinary or multidisciplinary dialogue.

All published articles are indexed throught international abstract base, Elsevier Bibliographic Databases that includes EMBASE, Compendex, GEOBASE, EMBiology, Elsevier BIOBASE, FLUIDEX and SCOPUS. Ministry of Science and technology development of Republic of Serbia admitted the Journal of Applied Engineering Science in a list of reference journals.

Publisher Institute for Research and Design in Commerce and Industry www.iipp.rs For publisher: Prof. dr Branko Vasić

Copublisher Faculty of Transport and Traffic Engineering – Belgrade University www.sf.bg.ac.rs

International Editorial Board Prof. dr Robert Bjeković, Germany; Prof. dr Jozef Aronov, Russia; Dr Jezdimir Knežević, England; Dr Nebojša Kovačević, England; Adam Zielinski, Poland; Doc. dr Miloš Knežević, Montenegro; Dr Vladimir Buljak, Italy; MSc Siniša Vidović, USA.

For copublisher: Prof. dr Slobodan Gvozdenović

Publishing Council Editor in Chief Prof. dr Jovan Todorović Faculty of Mechanical Engineering, Belgrade; Assistant Editor Dr Predrag Uskoković Belgrade Waterworks and Sewerage, Belgrade;

Editorial Board Prof. dr Gradimir Danon, Faculty of Forestry, Belgrade; Doc. dr Dušan Milutinović, Institute for Transport and Traffic CIP, Belgrade; Mr Đorđe Milosavljević, CPI - Process Engineering Center, Belgrade; Prof. dr Miodrag Zec, Faculty of Philosophy, Belgrade; Prof. dr Nenad Đajić, Mining and Geology Faculty, Belgrade; Prof. dr Vlastimir Dedović, Faculty of Transport and Traffic Engeneering, Belgrade; Dr Dejan Curović, Faculty of Mechanical Engineering, Belgrade; Doc. dr Vladimir Popović, Faculty of Mechanical Engineering, Belgrade.

ISSN 1451-4117 UDC 33 Papers are indexed by SCOPUS Journal Istraživanja i projektovanja za privredu (Applied Engineering Science) is also available on www.engineeringscience.rs

Nebojša Divljan, Delta Generali, Belgrade; Prof. dr Miloš Nedeljković, Faculty of Mechanical Engineering, Belgrade; Milutin Ignjatović, Institute for Transport and Traffic CIP, Belgrade; Dragan Belić, Transport Company “Lasta”, Belgrade; Dr Miljko Kokić, Zastava, Kragujevac; Dr Zdravko Milovanović, Faculty of Mechanical Engineering, Banja Luka; Dr Drago Šerović, Adriatic Shipyard, Bijela; Vladimir Taušanović, Belgrade Waterworks and Sewerage, Belgrade; Nenad Jankov, Power Plant Kostolac B, Kostolac; Ljubiša Vuletić, National Bank of Serbia, Belgrade; Dušan Đurašević, Euro Sumar, Belgrade.

Editorial Office Nada Stanojević, Aleksandra Stevanić, Miloš Vasić, Miloš Dimitrijević, Institute IIPP, Belgrade; Bojan Mančić, Ivana Spasojević, Faculty of Mechanical Engineering, Belgrade.

Printed by: R - print, Beograd Design and prepress: IIPP Journal of Applied Engineering Science 9(2011)2

EDITORIAL After nine years in the Journal Editorial Board, this is my first opportunity to write editorial for the improved magazine with new title and new policy of printing in English as main language. The decision regarding these changes has been made after careful examination of advantages and disadvantages of such a step. We were also aware that the language barrier or insufficient knowledge of English could discourage a number of national authors and possibly even higher number of potential national readers.

On the other hand, Ministry of Education and Science encourages publishers to publish their results in journals with impact factor as high as possible, which should also represent unique verification and international confirmation to the achievement of their work. Journal issued in English can count on the authors from the region and Europe as well, apart from the national authors. New Website, which is under construction at the moment, will enable potential visitors to read published papers on-line, to download and use them or give comments in their researches. Expected enlargement of readers will also have indirect impact on increased influence of our journal, namely the increased quotations of published papers - primarily internationally.

Improved journal has another important function. Its intention is to act as platform for comparing national and international research results and achievements in the area of engineering sciences. This is the priority at the moment, due to the ambitions to join the EU and become medium developed country with at least 7,000 EUR per capita. Out of that, not less than a half should be achieved through international trade of products and services. In order to achieve this, Serbia needs competitive economy, or wide range of products, which could be offered to international purchasers by the national economy. The issue is which products these should be since our goal should not be export at any cost but export usually called “sustainable” which should provide sufficient accumulation for future development.

All potential products can be arranged into three groups. The first contains products the production of which should not be entered into at any cost. These are mass products with which certain factories have covered global or regional market. This group includes, for example, ballpoint pens or single use lighters. When you hear the price and look where they are made, you ask yourselves how the seller finds the interest to sell these and the producer to produce them and ship to Belgrade.

The second group of products involves products the production of which should be started only in case of emergency, for a limited period of time, until getting ready for something better and more profitable. Here are two examples for this. The first is FAS, Fiat Automobiles Serbia. Revival of automobile production in Serbia is surely an act to compliment on. This factory and its manufacturing associates will provide employment for a part of citizens of Kragujevac who previously worked in Zastava or for their children. The second example is a big furniture producer and seller, Ikea. Disadvantages of such businesses lie in the fact that almost the same number of workers will be employed in FAS as the number of engineers who once used to work in Zastava. University in Kragujevac emerged from the need for educating experts for Zastava and its manufacturing associates at that time. Now, the situation differs greatly. Participation of domestic experts in the development of the new model was so low that even the national delegation during their visit to Torino knew more about the new model than the staff in Kragujevac. Similar situation will probably occur for every future automobile if the entire projects lasts, hoping it will. Ikea case is similar as well. Such a large system has central development in a Swedish village. It employs mostly the Swedes and occasional super talented foreigner. All those pretty items originate from that place. There is no need for designers in factories in Serbia. The conclusion is that such businesses should not be avoided, especially in our case; however, they should not be relied on if we really want “better” future. They provide for existence but not for improvement.

The third group of products is the right one which should be aspired to. These are the products which you personally conceive, prepare for production and launch on the market. For some time, you are the only one on the market thus you can command both the price and terms of sale. It can be seen on daily basis; however these products are rarely from Serbia. New experts and plenty of time, effort and money are required for the development of such products. These people will need quality training on faculties as well as the opportunity to obtain a part of their knowledge abroad. Also, new factories and new technologies are necessary as well as many other things. This chain has free space for the projects of the Ministry of Education and Science as well as for domestic scientific journals and thus for our new old Journal of Applied Engineering Science.

Institute for research and design in commerce & industry, Belgrade. All rights reserved

Journal of Applied Engineering Science 9(2011)2

Paper number: 9(2011)2,195, 297- 304

FORMATION OF FOLDED CONSTRUCTIONS BY USING CONTEMPORARY WOODEN TRUSSES Dr Nenad Šekularac* University of Belgrade, Faculty of Architecture Dr Jelena Ivanović Šekularac University of Belgrade, Faculty of Architecture Mr Jasna Čikić Tovarović University of Belgrade, Faculty of Architecture Folded structures represent three-dimensional constructions, i.e. spatial structures and as such belong to the field of structural systems. For very long time this type of construction has been realized in practice only in reinforced concrete and executed on site, which resulted in the use of a very complicated shutter. Development of prefabricated building led to the improvement of this type of constructions so that folded structures could be derived by assembly of prefabricated elements and their relationship, monolithization, on site. For decades, this type of construction was carried out solely in reinforced concrete and only in the second half of the twentieth century emerged the realization of folded structures using other materials: steel, wood, glass, polyester resin and a combination of different materials.

This paper the analyzes the existing folded structures made of wood as well as their systematization in terms of applied materials and shapes of cross-section of a folded structure, form of the basis and the method of execution. All the factors that affect the acceptance and transfer of load and static stability of spatial structures have also been analyzed. The focus of this paper is to research the possibilities and ways of forming folded constructions by using wooden trusses. A prototype of cylindrical folded constructions, realized in this system, is shown.

The area of application of wooden trusses as elements of the folded structure represents the area that has not been sufficiently explored in the world and our country, in the field of theory and practice.

This work and its actual results represent the expansion of knowledge of the area of folded constructions materialized in wood and contribute to modern engineering structures.

Key words: Wood, Wooden constructions, Wooden trusses, Folded constructions, Formation of folded constructions, Cylindrical folded constructions, Calculation of three-dimensional structures - spatial structures.

INTRODUCTION Wood and steel are the materials of which are mostly formed in-line bearing elements. Those elements, with different options of combination, can form a surface supporting elements, and, by further spatial combination, spatial folded structures. This way leads to the development of prefabricated folded structures with outstanding engineering solutions.

Striving for a more rational and economical construction, and using wood as a building material of exceptional mechanical, physical and aes-

thetical properties influenced the use of wooden trusses as elements of folded construction.

The term folded construction defines a folded form of construction, including constructions made of elements which from a folded shape by their mutual relationship in space.

Folded structures made of wooden trusses represent the follow-up of a research on development and possibilities of the application of wooden trusses in building practices. Three-dimensional spatial structures obtained in this way, formed by assembly of pre- fabricated wooden trussed elements with unified connections, enable industrial

* Faculty of Architecture, Bulevar kralja Aleksandra 73/II, Belgrade, Serbia; nseki@sezampro.rs

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production, simple operation and efficient on-site installation, which provides technological, functional and economic advantage of this construction compared to the folded structures of reinforced concrete.

This paper presents the analysis of possibilities of the application of wooden trusses as elements of the folded structure in theory. It has also been realized the prototype of cylindrical folded structure, span 24.0 m, as a test of a computational model of formation of folded construction using wooden trusses in which the node connections have been realized with denticular steel plates - connectors. In this way, there has also been carried out a practical examination of solution of interconnections of trusses, their stiffening by diaphragms formed of trusses, as well as the spatial stability of the structure formed in such way.

FOLDED STRUCTURES Folded structures - folds represent spatial i.e. three-dimensional structures, in which the size of elements is very small compared to the range of construction [4].

The term folded construction defines the folded form of construction, including constructions made of plates and structures made of sticks which make a folded form by their mutual relationship in space.

Some authors also name a folded structure the origami construction [1].

Folded structures of wood Due to limitations in terms of the possibility of overcoming large spans, as well as the reduction of world’s reserves of wood, other materials (steel, reinforced concrete) prevailed over wood early in the second half of the nineteenth century [3]. Modern technology has enabled good protection of solid wood and its processing into wooden products, creating new possibilities of the application of wood.

Wood represents a renewable material in nature (it fits into the modern trends of sustainable development) and has advantages over other materials: exceptional physical and mechanical properties, the material is environmentally friendly, has low own weight, it is easy to handle - suitable for mechanical processing, has a possibility of using simple structural joints, it is subject to recycling, and it is possible to move the

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structure made of wood [2].

Forms of folded wooden structures Folded structures made of wood are easy to transport, manipulation and assembly. This type of prefabricated folds on the basis of the primary supporting structure of the segment of folds can be divided into: • •

panel, truss constructions.

Panel folded constructions of wood Folded constructions of wood are usually formed as a panel (Figure 1.). Wooden panel folded constructions by their primary structure can be divided into: • • • •

full-wall panels, panels with grid supporting structure, panels with framework (Panel) supporting structure, panels with arch supporting structure.

Elements of full-wall panel folded construction are made as compact elements of solid timber or of laminated elements - plywood panels and the frame structure panels covered with plywood.

Folded constructions of wooden trusses Elements of folded structure can be formed of wooden trusses. By combining the trusses it is possible to get different forms of folded structures. Connecting the trusses is done on site.

Band members in the deflections and hip of the folded structure, and diagonal bars, are made from solid timber or laminated wood.

The choice of dimensions of the cross-section of the wooden truss rod is affected by: the span, load, shape and dimensions of the elements of folds. Structural design accurately determines the dimensions of each rod in the wooden trussed element.

Wooden folded structure of line elements of monolithic timber (planks and billets) can be divided into: • the system of folds Zahorski, • the system of folds Kroher, • folded construction in LKV System, • folded construction formed from members of glued laminated timber (Figure 2).

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Dr Nenad Ĺ ekularac and etc. - Formation of folded constructions by using contemporary wooden trusses

Figure 1. The roof of the factory hall constructed as a wooden panel folded construction, span 43.60 m, the architect Josef Lackner, Jenbach, Tyrol, Austria, 1996.

Figure 2. Folded truss structure Hartwald Clinic Pavilion, Bad Zwesten Germany, architect A. Frank, the designer of the construction Natterer,1977.

Folded structure formed of contemporary wooden trusses Contemporary wooden trusses represent industrialized system for prefabricated building of wooden roof structures of small and mediumspan. With this type of girder node connections are achieved by using special metal plate fasteners - connector.

Journal of Applied Engineering Science 9(2011)2, 195

Static analysis of structures of folded constructions formed of contemporary wooden trusses Nowadays, by using contemporary computational methods, software packages; it is possible to do analysis and structural design of various types of structures, from simple to very complex spatial structures.

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Dr Nenad Ĺ ekularac and etc. - Formation of folded constructions by using contemporary wooden trusses

In cooperation with the company Radimpex one of the authors of this paper, Nenad Sekularac, PhD, made the algorithm for dimensioning the elements of spatial wooden structures. Based on this algorithm the Module for dimensioning of wooden structures as a part of a software package Tower 3D Model Builder 6 was developed; company Radimpex (Figure 3). With this

program, apart from structural design of constructions and dimensioning of members from massive timber, it is possible to calculate design and dimensioning of the elements of glued laminated timber. The software package provides the choice of the standard by which the sizing of elements will be done, according to Yugoslav standards or according to European standards.

Figure 3. The appearance of Tower 3D Model Builder 6, Programme for static and dynamic analysis of spatial structures, displaying the intensity of normal forces in the member

Correlation between wooden trusses can be formed in several ways, but for this type of cylindrical folded form has been adopted the formation of connections of two lattice elements indirectly through a wooden bar - beam, as an additional element. The connection between the wooden trusses as elements of folds was achieved with screws. Combining the elements of the fold, two wooden trusses, is always carried out in the place of nodes of each element.

Since two adjacent wooden trusses of the folded structure do not lie in the same plane, but trusses mutually form an angle of 90 Âş; thus each truss prevents lateral buckling of the compressed band members in the neighboring wooden truss. Mutual spatial relationship of the elements of folded structure constructed in such way enables that band members of wooden trusses have a very small cross section in regard to the compressive force in them.

Cylindrical folded structure that is designed and presented in this work consists of triangular trusses. This spatial structure has 12 fields and

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the span is 24.0 m (Figure 4). Cylindrical form was converted into a polyhedral. Static system of the designed and constructed roof structure can be represented as a two-axle arch construction.

The construction is formed of triangular trusses that are rotated by 45 degrees in relation to the cylindrical plane.

One field of this folded structure consists of 10 base and 4 triangular trusses that are ½ of the base truss, spatially combined. In this way is formed a folded structure of cylindrical shape with a small number of various trusses, the maximum length of up to 9.0 m.

Prototype of the cylindrical folded structure As a logical consequence, after making the software package and computation of one model, appeared the aspiration for its implementation in practice. During the month of September 2005 the prototype of cylindrical folded construction was realized in the Fair of Civil Engineering in Budva, Montenegro.

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Dr Nenad Šekularac and etc. - Formation of folded constructions by using contemporary wooden trusses

to overcome the span of 24.00 m (and more), and successful use of the principle of mutual prevention of lateral buckling of compressed band members of trusses. Such construction is formed with a small number of different trusses, which makes it very rational in production and technological terms. In this way, the production is simplified, enabled transport of relatively small elements (up to 9.0 m long), and assembly and fitting of elements are easily done on site.

Figure 4. Isometric view of cylindrical folded construction made of wooden trusses

Conceptual and structural design of this construction was made by architect Nenad Šekularac, who used his own authorized programmes. The production of trussed elements was realized in the factory of “Lisina” company from Niksic, and was managed by architect Nebojsa Adzic.

The company “Lisina” from Niksic performed the building of this construction, with the instructions of the designer architect. Nenad Šekularac and architect. Nebojša Adžić as the main contractor.

During the design and execution of the construction the consultant was the Academician, Professor Vojislav Kujundžić, architect. The prototype of cylindrical folded structure, span 24.0 m, is constructed as a prototype of a hall, which consists of two fields of the folded structure (Figure 5) and represents only one segment of the cylindrical folded structure.

Figure 5. Isometric view of the prototype of folded construction

The prototype of the cylindrical folded structure, consists of 20 basic triangular trusses and 8 which are ½ of the base truss. (Figure 5, Figure 6). Formation of a structure in this way enables Journal of Applied Engineering Science 9(2011)2, 195

Figure 6. View of the calculation of structures in Tower 3D Model Builder 5.4 programme, from the period when the structure was designed and carried out.

In order to stiffen the folded structure, the diaphragms have beenformed in places of the change of the inclination of the roof planes of the folded structure, and the axis of the longest vertical rod of the truss core element from which the folded structure is formed. Diaphragm, apart from spatial stiffening of the structure, also has the role to receive the load of the roofing, snow and wind. (Figure 8). Rafters placed on the roof plane, in the area of truss nodes, are also designed so that in addition to accepting the load of the roofing, snow and wind, have a role to stiffen the cylindrical folded structure (Figure 8).

All workshop documentation and estimate of the connections by connectors have been made using a programme for calculation and design of modern wooden trusses (autor of software Nenad Šekularac, PhD, engineer of architecture).

The estimate foresees for the use of wood of class II quality, conifers, adequately protected by coatings. Metal connectors LKV-C are made of steel, C-0146 quality, 1.50 mm thick, previously protected from corrosion by zinc. Hardware has been protected by paint and painted with finishes.

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Figure 7. Comparative view of 3D model of the calculated and performed cylindrical folded structure - prototype

Figure 8. Diaphragm connection detail and rafters of cylindrical folded structure

Installation of a prototype of cylindrical folded structure When installed the designed system proved good results. The first step in the assembly was to form a package of four triangular elements of folded structure, connected to diaphragms which also represent the rafters that support the roofing with all the layers of insulation. Formed packages of trusses are interconnected into a fold-

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ed construction on the ground (Figure 9). The structure was put on the projected position by lifting - rotation with a car crane (Figure 10). In this way the use of large scaffold was avoided, and only handy elevators were used, since the packages of 3:56 m height were moved. Almost all work was done on the ground, allowing easy and quick installation of the complete structure (Figure 11).

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Dr Nenad Šekularac and etc. - Formation of folded constructions by using contemporary wooden trusses

Consumption of material in making a prototype of cylindrical folded structure

Figure 9. Installation of cylindrical folded construction on the ground

For the prototype of a 24.00 m span, which consists of two folded fields, the total width of 3.56 m, and covering the surface of 91.35 m2 and 110.00 m2 of developed area of the roof, was spent a total of 4:47 m³ of wooden elements, 175.33 kg of melal plate fasteners and 295.66 kg of metal bond elements - along with the shackle and bolts. The total consumption of material to build a prototype of cylindrical folded construction is given in Table 1, Consumption of material needed for the performance of a prototype of cylindrical folded structure[5]. It is necessary to emphasize that the total amount of timber includes elements which prevent lateral buckling of the structure-diaphragm and the rafter, as well as elements for mutual connection of adjacent sticks of top and bottom trusses.

Table 1. Consumption of material needed for the performance of a prototype of cylindrical folded structure Recapitulation By m² of horizontal projection Wooden

By m² of developed roof surface

0.049 m³/m²

0.041 m³/m²

Metal plate fasteners

1.919 kg/m²

1.594 kg/m²

Hardware and metal bond elements

3.237 kg/m²

2.688 kg/m²

elements

Figure 10. Lifting the prototype of construction with a car crane

Total weight

~ 30.156 kg/m² ~ 25.282 kg/m²

CONCLUSION

Figure 11. Mounted prototype of cylindrical folded structure at the Fair in Budva

Journal of Applied Engineering Science 9(2011)2, 195

Folded roofs, as well as three-dimensional roof structures, are formed by the assembly of prefabricated elements - wooden trusses, with unified joints, and thus enable industrial production of wooden trusses as elements of folded structures. The aspiration for more economical and rational construction resulted in the selection of wood as a building material with excellent physical, mechanical and aesthetic properties. With the application of the principles of unification and systematization of wooden trusses as basic elements of the structural system, with a small number of different elements, we get a flexible

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system of building of folded structures in terms of technology and facilitate the process of production, transport and installation of folded structures.

The research presented in this work confirmed that the formation of folded structures by the use of wooden trusses represents a modern technical and technological solution. Folded structures formed by using wooden trusses can meet high aesthetic requirements. From an economic point of view this type of folded structure has an extremely low consumption of cut timber and a possibility of rational utilization of material, since the constructions with a big span can be obtained from members of a relatively small dimension.

In terms of a formal and visual effect with formation of folded structures by using wooden trusses we can get shapes and design solutions that make the structure obtained in this way different and special compared to this type of structures realized in a different material.

This paper should contribute to the reaffirmation of wood as a material and trusses as technologically improved elements that enable the fulfillment of modern architectural requirements for design and construction of spatial structures.

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REFERENCES 1) Hani B., Yves W. (2008) Origami - Folded Plate Structures, Architecture, THE PROCEEDING OF 10th WORLD CONFERENCE ON TIMBER ENGINEERING, Miyazaki, Japan, IBOIS-CONF-2008-021 2) Ivanović Šekularac J. (2010), Functional, and Representational potential of Wood as an Element of Architectural Buildings′ Lining, doctoral dissertation, Faculty of Architecture, University of Belgrade, pp.3-5 3) Petrović М. (1978) Arhitektonske konstrukcije II, Izdavačko-informativni centar (ICS), Beograd, pp. 5 4) Romić S. (1980) Ljuskaste konstrukcije, Naučna knjiga, Beograd, pp. 100 5) Šekularac N. (2010), Shaping of the Folded Structures by Using Wood trusses, doctoral dissertation, Faculty of Architecture, University of Belgrade, pp. 121 Paper sent to revision: 26.02.2011.

Paper ready for publication: 21.04.2011.

Journal of Applied Engineering Science 9(2011)2, 195

Paper number: 9(2011)2,196, 305 - 316

INTEGRATIVE URBAN DESIGN IN REGENERATION - PRINCIPLES FOR ACHIEVING SUSTAINABLE PLACES Tatjana Mrđenović* University of Belgrade, Faculty of Architecture Urban design is nowadays challenged by contemporary concept of regeneration. Regeneration meens creating sustainable places, with specific identity, protection and promotion of cultural values, social cohesion and economic prosperity. The aim of the paper is to discussa role of urban design as a transformative insrument in the regeneration process. It will question the possibilities of urban design to provide strategic framework for regeneration through the process that enable creative milieu for integration of different developmental aspects and interests in plural society. The scope of the research is bounded by the urban design process in line with rational and collaborative approach in urban decision making.The theoretical and conceptual framework will be elaborated on the case of Plan of tourist valorisation of Golubac fortress in Serbia, as a place of great cultural importance and as a generator of socio-economic development in Municipality of Golubac. Describing an integrative model for urban design as an instrument for regeneration is a main contribution of the paper.

Expected results of the research are definition of basic principles for achieving sustainable places in regeneration.

Key words: Urban design, Regeneration, Sustainability, Urban decision making.

INTRODUCTION In line with contemporary dynamic relations in the process of globalization the identity and quality of places is crucial factor of place recognition in global network [1].The competition for global recognition opens many chances to local cultures for socio-economic development, developing new relations in global networking. According to Castells local community and local cultures becomes core factor in cultural identity [2],[3].Globalization as complex process carries plurality of cultures, interests and needs that should be recognized and accepted in urban development process.

The plurality carries conflicts and contradictions that are balanced by concept of sustainability.

Sustainable development 2 is a process of balancing plurality of cultures, interests and needs, integrating them into coherent whole [4],[5] { 2 Concept of sustainability has evolved from the study “Limits of growth 1972” and represent rational paradigm in managing resources systematically through feedback on the effects of growth using technology (according to op-

timistic and pessimistic estimations on future development of renewable and non-renewable resources) [46]. After the study, sustainability is supported and developed through various documents on UN and EU level, such as [44] [43] [42] [41] [4] [38] [39], [40], [47]. Authors in Serbia puts focus on managing resources in sustainable manner, in such a way Brković emphasize 3E concept [45], and Janić managing resources in integral manner [48]}.Baker recognizes four models of sustainability according to their philosophical orientation: anthropocentrism and eco-centrism. The models are defined as ideal (which is on the extreme position of eco-centrism, where nature is intrinsic value), Strong model of sustainable development (which is between eco-centrism and anthropocentrism), Weak sustainable development, and Pollution control (which is on the outermost position of anthropocentrism) [6]. This paper will stand for the models that are more on the side of anrtopocentrism, as culture is a product of civilization, taking into account environmental and ecological problems through integrated approach.

* Faculty of Architecture, Bulevar kralja Aleksandra 73/II, Belgrade, Serbia; tmrdjenovic@arh.bg.ac.rs

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Tatjana Mrđenović - Integrative urban design in regeneration - principles for achieving sustainable places

Integration of sectors of sustainability - economy, society, environment (both built and natural) is conceptualized through different diagrams (models): The Venn Diagram, The Nesting model, The Mercury model and The Swedish prism model. The last takes into account institutional development as fourth dimension of sustainability [7]. Serbia has adopted National strategy of sustainable development where it defines tree pillars for sustainability in domestic context: 1) Intensive care for environment(built and natural), 2) Knowledge economy which means innovation, education and “software economy” that is oriented towards commerce, tourism, information society, 3) Social solidarity 3 [5]. The concept gives new meaning to regeneration. { 3 Also, the strategy lean on Venn diagram of integration economy, society and environment (Image 1 in Annex) in a way that economic growth is possible if it has positive effects built natural environment and social justice [5]. Therefore, in practice in Serbia it means gradually implementation of concept starting from “pollution control” towards Venn diagram} Taking into account sustainability as a global concept, contemporary approach to regeneration means creating sustainable places, integrating different developmental sectors, identities and interests into place creation through decision making process [7],[8], providing quality of life for citizens {Which is in line with the concept of New Urbanism, (49)} . In Serbia regeneration is, according to Bazik: “Process of defining integral policies that integrates global and local level, through inter-sectoral relations between economic, social, environmental and institutional development” [9]. Also, Vaništa Lazarević says that regeneration in Serbia needs multidisciplinary approach, which bounds architects, urban designers and planners, landscape architects, spatial planers, economists, financial experts, sociologists, marketing experts. Apart from interdisciplinarity, regeneration needs participation, wider social inclusiveness as well as public-private partnerships that contribute to active regeneration [10].

This also, puts forward urban decision making process as a carrier of quality of regeneration.

Globalization and sustainable regenerationframe new context for urban design and its relation to development. Theories of urban design vary in line with different socio-economic context and it is seen more as a product or process. In line

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with complexity of regeneration and its focus on decision making, I would say that urban design is a process of integration rational and collaborative paradigm of decision making, mediating different realities through communicative action.

Therefore, the hypothesis is that urban design is the field werethis integration is possible to achieve, developing “hard” and “soft” infrastructure4 for cultural diversity, diversity of needs and interests. {4 According to Healey “hard” and “soft” infrastructure are necessary preconditions for urban creativity, where “hard” mean rules, procedures, protocols, and “soft” social networking based on trust and reciprocity} Seen as a process of place creation, urban design integrates different dimensions of space production [34].

Seen as a process of decision making, urban design can provide sustainable framework for regeneration considering main principles of sustainability. EU recognizesneed for developing European methodology for managing cultural heritage in the frame of sustainable development, creating an instrument for qualitative and quantitative assessment of public and private investments on developing cultural heritage, defining the role of cultural heritage in providing new jobs, creating preconditions for sustainable development through partnership between public, private and civil sector [11]. Serbia is in the process of expert and public discussion on the model of integration that is appropriate for domestic context.

ROLE OF URBAN DESIGN IN REGENERATION This chapter will discuss the role of urban design in regeneration in line with different sectors and dimensions that should be integrated in sustainable development. According to Bazik conditions for regeneration in domestic context are extremely specific. In relation to socio-economic transition, process re-affirms urban design as an initiator of regeneration, that is on the way towards approach in developed countries where urban design practice is an integrative process of urban production [9].

On the other hand, the need for innovative and integrative approach in regeneration questions possibilities of urban design to become an integrative instrument5 . The discussion will be led by the thought that urban design as multidimensional process can provide creative solutions for difJournal of Applied Engineering Science 9(2011)2, 196

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ferent developmental sectors of sustainable regeneration: economy, society and environment, overcoming problems of rational and collaborative paradigm in urban decision making through communicative action. This position should give a holistic answer to the problems that standagainst sustainable regeneration in Serbia, both in theory and practice. { 5 After many years of co called “rational” or functionalistic urban planning”, after decades of a kind of naïve and aggressive radicalism in the field of cities, after so many of ‘’original” concepts and “new” options concerning urban milieu and fabric – time is coming to remake and reconstruct the whole body of urban philosophy and kind of “recycling urban process” not only of spaces, but also of ideas and principles, is becoming obvious. I promote, in this sense, a kind of “sensitive urban planning”, taking care of all dimensions and interests in urban matters, trying to combine the pragmatic realities and high ideals together, and developing pluralistic, complex and integrated thinking of the urban functions as of the urban spaces.” [35]} The holistic thought of urban design integrates different crosscutting dimensions where it is produced. Firstly, it is a space of imagination and creation of urban designers when it is subjectiveexpressive process of creating specific identity of places. In the context of social production of space it is more objective-rational or socio-communicative process of creating new socio-spatial relations and its visual artifacts. Thirdly, it is an interdisciplinary process as a field for communication of different expert’s view pointsthrough argumentation. Fourthly, urban design can be seen as a technical process that represents politics and regulation form higher level [12].

On the other hand Tošković and Petrić emphasize different theoretical orientations (TM: I would say dimensions) of urban design that are mutually exclusive 6 (functionalists, systematic, humanistic, formalistic) {6TM: these orientations are mostly correlated to the urban design dimension of socio-spatial practice}. Authors openinspirational questions 7 for urban designers in search for an integrative instrument of positive aspects of each theoretical approach [13]. According to Živkovićurban design in Serbia is reduced to designing large scale designs and focuses on physical space and its esthetical dimensions.

In contrasts, she points out that contemporary tendencies lead towards fusion of different disJournal of Applied Engineering Science 9(2011)2, 196

ciplines and different dimensions of space production, and urban design as follows [14]. {7 ‘’In that manner, in attempt to understand different theoretical orientations, researcher should answer to the following questions: 1) How cities are versioned in each?, 2) How each of the orientation is proofed in the process of urban design and planning decision making?, 3) What factors are instruments in achieving quality of urban space?, 4) On which methods each of the orientation lean on?, 5) What is their relation to the past?, 6) What are the attitudes of proponents towards urban centers?, 7) What are their typical critiques?”(13)}.In general this position holds Nikezić, when he elaborates different instruments8 for territorial development in Serbia. His observation is focused on the need for creating and defining wide range of instruments9 that will enable horizontal and vertical integration of territorial governance10 [15]. { 8 TM: Concept of territory integrates all factors of its integrative development, including also disciplines such as urban design is.

9 Nikezić makes distinctions between three types of instruments that should be developed: (1) Universal instruments, covering the whole territory of Serbia, (2) Particular instruments, covering undeveloped or endangered parts of the country, (3) Specific instruments independent from spatial scale, but in relation to the specific public interest that should be protected or promoted. (15) For this research the relevant is last mentioned.

10 TM: institutional development towards multilevel governance is fourth dimension of sustainable regeneration Swedish prism model.} This paper will be led by holistic approach to urban design where it is seen as a process of communicating its different dimensions leading to integration of multilevel governance as well as different developmental sectors when it can become specific instrument for regeneration.Therefore, the process of urban design can provide positive atmosphere for communicative action negotiating different viewpoints and interests into coherent whole, becoming an integrative, specific instrument for different theoretical orientations, sectors of sustainability, urban design dimensions. I would say that key words for urban design process as are creativity and communication through argumentation.

Seen as a communicative process it is strongly related to the traditions of urban decision making when it is more rational (“top-down”) or col

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laborative (“bottom-up”) process. The key factor in this dilemma is the type of rationality that is practiced in wider social context. Rational paradigm is based on objective rationality and positivistic approach to development. It means setting and evaluating all possible solutions and forming defined scope of action.”It is based on instrumental rationality, namely on expert’s analysis which enables setting of goals, identification of alternative courses of action, evaluation of the means by which the goals would be achieved and the creation of systems of implementation”[16]. In urban planning and design theory it is mostly supported with Faludi’s model of planning agencies where they practice systematic and rational approach to urban development integrating different levels of governance into coordinated multi-planning system [17].

The main critique to rational paradigm comes from Simon’s rational constrains where it is not possible to generate and evaluate all possible alternatives because of constrains of human thinking. On the other hand Lindblom in his theory of “muddling through” says that rational approach to development is not realistic in the real politics with complexity of different interests and stands for generating solutions in incremental approach [18]. Both systematic and incremental approaches have their positive and negative side. We can’t for sure perceive reality in positivistic manner, and on the other hand if we lean on incremental approach we can be in situation without any developmental options.

Healy in theory of collaborative planning sees urban development as putting fragments of viewpoints and interests into common picture through communicative process of bottom-up participation in different social arenas. She argues rational paradigm saying that it is not applicable in plural society and its complexity of different interests and thoughts. On the other hand, Bajec identifies main risks for collaborative/communicative paradigm, especially in domestic context. The risk is that participants can be in situation when they do not decide based on their interests [16], when collaborative decision making becomes a field for manipulation, or as Vujošević and Petovar say “an arena for organized mobilizing biases” [19]. According to Habermass it means instrumental action that focuses of gaining success of individuals in contrast to strategic and communicative action that11

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are socially oriented [20], [21] providing developmental social capital [22] in process of strategizing development. {11Habermas make differences between instrumental and communicative action in relation to effects that they have to further social processes. The further provides consensus and win-win solution in development. [20]} Healy stands for Habermasian communicative action through argumentation and sees strategic development as defining framework for action, more than defining final set of actions. She says that process of urban decision making should frame development through socio-sensitive decision making, developing “hard” and “soft” infrastructure as a base for creative milieu [23].“A creative milieu is a place…that contains necessary preconditions in terms of “hard” and “soft” infrastructure to generate flow of ideas and inventions. Such a milieu is a physical setting where a critical mass of entrepreneurs, intellectuals, social activists, artists, administrators, power brokers or students can operate in an openminded, cosmopolitan context and where face to face interaction creates new ideas, artifacts, products, services and institutions and as consequence contributes to economic success.”[24].

Creative milieu can be an arena that makes preconditions for communicative action, integrating actors from different developmental sectors, as well as from public, private and civil sector through building bridges and partnership in fragmented societies. By my opinion both paradigms rational and collaborative arein line with sustainable and integrated development in plural society. Rational paradigm provides vertical and systematic integrationwhile collaborative horizontal mediating different pictures of reality into coherent whole.

Also, in plural societywhere interests should be recognized at all levels, integrated approach in urban decision making integrates positive factors of rational and collaborative paradigm, providing sustainable framework for development.

Considered as decision making and communicative process, as well as creative and imaginative, urban design can provide framework for sustainable regeneration. In relation to urban12 planning urban design as a creative process makes crucial difference to planning in terms of regeneration. I would say that seen as a communicative process of integrated decision making, it can provide strategic framework for regeneration. Hildebrand Frey defines role of urban deJournal of Applied Engineering Science 9(2011)2, 196

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sign as strategic process of framing places on different spatial levels with emphasis on identity as a core factor of integration [25]. Brković, gives high importance to definition of adequate strategy for regeneration of devastated urabn spaces in Serbia over past decades. As Hildebrand, she stands for the strategy that should provide a framework for activation of multilevel urban potentialities, defining both stimuluses for its development, lining on specifities and special Serbian identity [26]. { 12Uskokovic defines planning as “open system with adaptive factor that manages and directs activities.” [36]} Seen as a strategic process,providing framework for action, urban design is composed of different phases in urban decision making.

(P) Preparing, (V) Visioning, (A) Analysis of present conditions, (S) creating aims, objectives, alternative scenarios as strategies defined through different programs, projects and activities and (I) Implementation.The ways of the travel through phases differ according to specific context and are given in the figure 1:

Figure 1. Different ways of travel through strategic process in integrated urban design (UN-Habitat & SIRP, 2005)

(1) is applied in situations when there are urgent problems that should be solved, (2) is applied in situations when desirable future is clear, (3) is applied on bigger spatial areas and includes long term development, (4) is applied on midterm development [27]. In line with sustainable regeneration, integration of rational and collaborative paradigm should be practiced in each of the phase, considering specific context and situation. For this to be achieved necessity is to describe an integrative model of the process of urban design decision making.

INTEGRATIVE MODEL FOR URBAN DESIGN PROCESS This chapter will give an integrative model for urban design process as a theoretical and methodological support to regeneration. The model should enable creating quality of urban spaces that both protect specific values and enable development towards sustainabilityand creating “collective form ” 13 that is founded on collective/ collaborative good reasoning. The model will be elaborated on the case in next chapter, when the hypothesis of the research will be proofed or refuted. The model and the case will be a base for generating principles for sustainable places in regeneration. {13 the problem of wrong reason (TM: related to collective form) has its own history. Its fragments are found in modern urbanization of the cities in Serbia, at the neighborhood level – shaped by the tension between power directives and the desire of ordinary people.” [54]} Discussion on type of rationality that is adequate in crating sustainable places for regeneration of urban areas of cultural importance led research to the concept of integrated development, that make linkages between different sectors of sustainability and levels of governance. Folić under-

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lines need for integrative strategies in Serbia that will harness economic, social and environmental sectors of sustainability in regeneration. She believes that only in this manner urban areas can develop towards provision of quality of life for its citizens [28]. Here, we come again to the need for describing integrative model in regeneration using rational and collaborative approach.

Theoretical discussion, in previous chapter, emphasized positive and negative sides of rational and collaborative paradigm in urban decision making. It is said that each of them can have developmental characteristics, gained through different practice of rationality. According to Bajec, Serbia is in the position of two processes: (1) reevaluation of socialist and post-socialist rational approach, and (2) introducing, mostly by international organizations, collaborative model through different non-salutatory documents and strategies [16].My opinion is thatthis trendcan branch in two alternatives as final outcomes.

The first, I would say negative one, willlead to the confusion in choosing adequate approach in regeneration which will stop or slow development. The second, optimistic one, will develop innovative theory and instruments for regeneration in Serbia towards collective action.

Position that I stand for is optimistic one, based on the assumption that communicative action can integrate positive and overcome negative aspects of each the paradigm, using creativity as a mean for open communication, flow of ideas and thoughts.14 Therefore argumentative approach use creativity to make linkages in strategy making crosscutting both paradigms providing particular identities, interests and needs to be recognized as well as having an ideal picture of development as a coherent whole (see Table 1). {14According to Foresters’s “designing as making sense together” [31]}

Table 1. Creating strategies in rational and collaborative manner, T. Mrdjenovic according to Healey CREATING STRATEGIES RATIONAL PARADIGM

COLLABORATIVE PARADIGM

Type of strategy

Definite set of action

Framework for action

Type of knowledge

Positivistic

Social

Type of connections

Rules, procedures, web

Social networks

The role of urban designer

Consultant to decision makers

Facilitator of in the process of consensus building

Role of the strategy

Rational assessment of in the way of setting the goals and means for the implementation

Creating strategy means building up hard and soft infrastructure

Pristup

Problems, facts and values are positivistic.

Problems, facts and values are in social knowledge.

Type of space and place

Institutional space

Shared place

Place where strategy is created

Public agencies

Social arenas

Space for integration through communicative action through different social arenas

Space for integration is achieved though different social arenas as spaces for divergent communicative networks enabling creativity and argumentation, together providing innovative and realistic development. Therefore, we can developFaludi’s model of multi-planning agencies by providing social arenas were diversity of interests and conflicts are present, which is in line with Healy’s theory.

It will provide an integrative model for the urban design process in regeneration. (see Figure 2).

Figure 2. Integrative model for urban design process in regeneration, T. Mrdjenovic

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The Figure 2 shows different types of social arenas according to their position, inside or outside the agency. Their purpose is to gather various formal and informal communicative canals. Social arenas inside the agency are oriented towards building capacities through trainings on different topics relevant to governance (such as better communication, participatory planning, conflict management, etc). The second type supports solving complex public problems, like regeneration is, that goes beyond the boundaries of one organization or institution. This type can be in two positions, where the first is in between two agencies, and the second is in between multi-planning agencies and surrounding. The forms of social arenas vary according to their position and phase of developmental process. They can be organized through different workshops, round tables, public discussions, trainings, or presentations.

Social arenas should support different dimensions of urban design process like creativity, social and interdisciplinary communication, imagination and argumentation using appropriate methods and techniques. Methods and techniques of integrative urban design process can be grouped in three types: 1) disciplinary, 2) interdisciplinary,3 )collaborative. In each of the phase of the urban designprocess they support different expertise, creativity, raising awareness, argumentation, and collaboration. Some of them are Morphological studies15 , Art workshops, Space syntax analysis [51], Planning for real, Urban design workshops, Urban design games, Systematic assessment of urban space, Digital maps, Thematic workshops [52], [53] , Diagrams like SWOT, Problem tree, Objective tree [52], [53]. { 15 Morphological studies are very important for defining identity of place as one of the dimensions of sustainable regeneration. “The second principle of morphologicalresearchers in architecture and urbanism is the principle of identity, so that for morphological researchers it is necessary to make corresponding adjustments of the objectives and instruments to each individual situation.” [50]} In general, they should provide a space for communicative action leaning on creativity as a mean for overcoming obstacles for open communication. In that manner it integrates categories showed in Table 1.Also, my position is that the model is base for creative milieus were different social arenas stands for “soft” and planning agencies for “hard” infrastructure.The Journal of Applied Engineering Science 9(2011)2, 196

model will be elaborated on the example of Plan for tourist valorization of the Golubac fortress.

INTEGRATIVE URBAN DESIGN STRATEGY FOR TOURIST VALORIZATION OF GOLUBAC FORTRESS This chapter will present a Plan for tourist valorization of Golubac fortress 16 as an integrated urban design development strategy. The strategy will be discussed from the point of creating framework for development, using integrative model for regeneration. The purpose of the plan is to provide flexibility in regeneration in relation to available financial, organizational and legislative resources. In that manner plan treats different dimensions of sustainability: protection and promotion of cultural heritage and place identity, development of social capital in inclusive manner and economic development 17 that is sensitive to natural resources in near surrounding Danube river and National park of Djerdap. The main aim of the strategy is to activate tourist potential of the fortress in short period of time. {16 The plan was done in collaboration with GTZ, Faculty of Architecture University of Belgrade, Stefan Krell consulting and Municipality of Golubac. Authors of the plan are: UrošRadosavljević, TatjanaMrđenović, Stefan Krell, JovanaPavić 17 In line with sustainable regeneration Nikolić identifies preservation of authentic of place, that is guaranteed by The Nara document of authenticity (37), as one of main problems for economic development, as well as identification of contemporary functions inside historical sites. [55]} Methodological approach considered different developmental sectors of sustainability through wide participation: (1) Improvements of organizational and governance capacities on local level, through trainings, (2) Improvements of legislative framework, producing relevant statutory plans, (3) Improvement of mobility, (4) Improvements of stability of the fortress, (5) Visual identity and character of place, (6) Promotion and information, (7) Development of tourist infrastructurein surroundings .Also, the process flowed through different phases of the strategizing showed in the Figure 3. This way was chosen as appropriate one as it was related to mid-term development, where focus was on defining sustainable measures that should activate tourist potential of the Fortress in short period of time.

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Figure 3. The process of strategizing applied to the case of Golubac

Participation included rational and collaborative approach in which “hard” infrastructure was provided by inclusion of organizations and institutions form local, regional, national and supranational level. Complex issues of the Fortress regeneration, that crosscut different developmental sectors of sustainability, were communicated in “soft” spaces using different types of social arenas as well as appropriate methods and techniques.

Therefore, plan used integrative model of urban design process to achieve sustainability in regeneration setting up creative milieu for development.

Creative milieu provided open dialogue and flow of ideas, information and communication towards identification of main problems and developmental potentials for regeneration. Each developmental sector wasconsidered through discussion of problems, opportunities, developmental alternatives, strategies and measures in forms of workshops, round tables, meetings, public presentations. Therefore, second type of social arenas was established using imaginative/creative, collaborative and rational methods and techniques. Social arenas that enable building organizational capacities were recognized as specific measures to be implemented in future.

Argumentative approach was supported by using different diagrams like SWOT, Problem tree, Objective tree. The process led towards identification of problem causes to define specific measures that are appropriate and can be defined as separate pilot-projects. In that manner 11 measures were identified and cover all four dimensions of sustainability (Swedish prism model). The measures can be implemented separately and are base for application to national or EU funds. The structure of each measure is in line with its purpose and can be a project for

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implementation. Therefore each measure has its objectives, three different developmental alternatives, and effects to socio-economic development, as well as costs of implementation of each measureThe process of creating the strategy had initiated different activities on local level, like providing necessary legislative documents and project documentation as well as improving organizational capacity. Strategy has positive effects on other programs and projects that are in line with Tourist activation of the Fortress. Expertise is included in preparing material for integrative urban design process and in its facilitation. Principles of the strategy are: (1)Integrating sectors of sustainable development, (2) Providing framework for action,(3) Openness and flexibility in implementation, (4) Inclusiveness through participation and collaboration, (5) Education and trainings,(6) Character and identity of place, (7) Improvement of mobility in the area, (8) Promotion of tourist attractions, (9) Diversity of activities, (10) Providing new jobs.

CONCLUSIONS - PRINCIPLES FOR ACHIEVING SUSTAINABLE PLACES Cultural heritage with its unique values is a crucial factor in European identity, based on tolerance and democracy. Wide knowledge of cultural diversity is a base for tolerance and respect, overcoming differences and building bridges between different cultures as a unique part of European identity. Cultural heritage is recognized as socio - economic potential and each country should develop alternative strategies for sustainable regeneration. (29)(30)(11). As regeneration crosscuts different sectors of sustainability in place creation it is best achieved through urban design process.

Urban design, considered as decision making and communicative process, as well as creative imaginative (Creativity promotes and develops special identity) and rational can provide framework for sustainable regeneration. Setting up a creative milieu it becomes an instrument for integration of plural identities, interests and needs into a coherent whole, incorporating different types of social arenas into multiplanningagency system. Such a model provides social capital that has developmental characteristic enabling and facilitating partnerships between public, private and civil sector on local, regional, national and supranational level. Therefore, as Journal of Applied Engineering Science 9(2011)2, 196

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Figure 4. Integrative model of urban design process implemented on The Plan for tourist valorization of Golubac fortress, T. Mrdjenović Journal of Applied Engineering Science 9(2011)2, 196

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a creative and communicative process it can be an instrument of integration, providing specific identity and framework for development.

The case of Golubac has two important dimensions. The first is creative milieu that was set up during the process of generating the Plan., using creativity of urban designers to define universal unity integrating bottom-up and top-down interests and needs, defining as Forester says “common meaning”(31)for overcoming differences.

That meant establishing social arenas during the process, bounding stakeholders from different agencies, institutions and organizations, that come from public, private and civil sector and are on level, regional and national level.

The second dimension, enables sustainability of integration in further implementation of the plan establishing working group, management unit or person in charge as strategic planning agency attached with social arena for communicative action. The strategic agency should provide both rational and collaborative approach through procedural and systematic planning, also with discussing and collaboration within social arenas for creation new solutions to possible future problems and funding. Also, Measure panticipates social arenas within planning agencies, for building capacities through trainings, that will enable effectiveness and efficiency of the Plan implementation, it’s possible reevaluation, or wider strategizing of the whole municipality of Golubac (which would need different process of integrative urban design, including visioning as well), in iterative manner. Therefore, the integrative model applied on the case develops “hard” and ‘’soft” infrastructure, and is shown on the Figure 4 (see Annex): Integrative model of urban design process applied on the case of Golubac, T. Mrdjenovic.

According to previously elaborated I can say that the hypothesis of the research is proofed, meaning that creativity of urban design and urban designers can provide preconditions for communicative action, overcoming obstacles for open communication, facilitating collective objective reality and future through argumentation and good reasoning, neglecting individual or group “simulations and simulacrums” [32], main disadvantages of collaborative approach.

In that manner process of urban design can provide an integration of rational and collaborative paradigm in urban decision making.

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According to theoretical discussion, and its application on practical exampleI would define main principles for specific urban design integrative instrumentin regeneration: •

• • •

•

It should provide strategic framework for regeneration in rational and collaborative manner, It should integrate different sectors of sustainability, It should integrate different levels of governance, policies and legislative, It should be inclusive for stakeholders on local, regional, national and supranational level, It should promote and develop specific character and identity of place.

ANNEX

Figure 5. Venn diagram in National Strategy for Sustainable development in Serbia, (ВладаРС, 2009)

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40) UNEP. Declaration of the United Nations Conference on the Human Environment. ttp://www.unep.org/Documents.Multilingual/ Default.asp?documentid=97&articleid=1503 . [Online] June 16, 1972. [Cited: 11 9, 2010.]

41) EU. Sustainable Development Strategy. s.l. : EU Commision, 2001.

42) Lisbon Strategy. s.l. : EU Commision, 2000.

43) European urban charter. [Online] March 18, 1992. [Cited: 11 9, 2010.]

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44) Charter of European Cities and Towns towards Sustainability. http://ec.europa. eu/environment/urban/pdf/aalborg_charter. pdf. [Online] 1994. [Cited: 11 9, 2010.]

45) Brkovic, Milica Bajic.Odrzivost i grad. Beograd : Arhitektonski fakultet Univerziteta u Beogradu, 1996.

46) Tietenberg, Tom and Collins, Harper.Limits to growth: A report to Club of Rome/ Environmental and natural resource economics. s.l. : Sierra Club Books, 1992.

47) WCED. Brutland report - Our common future. http://www.re-set.it/documenti/1000/1800/1850/1856/brundtland_reportpdf.pdf. [Online] 1987. [Cited: 11 9, 2010.]

48) Janić, Miodrag.Održiv razvoj ljudskih naselja zemalja u tranziciji. Beograd : Direkcija za građevinsko zemljište i izgradnju, 1997.

49) CNU. New Urbanism Charter. http://www. cnu.org. [Online] 1996. [Cited: October 1, 2010.]

50) Đokić, Vladan. 2009,Morphology and Typology as a Unique Discourse of Research.

Serbian Architectural Journal, pp. 107-128.

51) Hiller, Bill.Space is the Machine. London : Space Syntax, 2007.

52) Fisher, Fred. Building Bridges Through Managing Conflict and Differences. s.l. : FPDL, LGI, UNCHS, 2006.

53) Buildnig Bridges Through Participatory Planning. s.l. : FPDL, LGI, UNCHS, 2005.

54) Milojevic, Milica. 2009,Re-conceptualization of the Idea of Neighborhood in Post-socialist Belgrade. Serbian Architectural Journal, pp.

45-64.

55) Nikolić, Marko. 2011, Visitors’ Centers at Archeological Sites in Serbia as an Imput for Sustainable Development of the Country.

Journal of Applied Engineering Science, No 1, Vol 9, pp. 253-268.

Paper sent to revision: 24.02.2011.

Paper ready for publication: 26.05.2011.

Journal of Applied Engineering Science 9(2011)2, 196

Paper number: 9(2011)2,197, 317 - 322

MICROSTRUCTURE EVOLUTION AND SINTERING KINETICS OF ZnO Darko Kosanović * Serbian Academy of Sciences and Arts, Institute of Technical Sciences Mr Suzana Filipović Serbian Academy of Sciences and Arts, Institute of Technical Sciences Dr Nina Obradović Serbian Academy of Sciences and Arts, Institute of Technical Sciences Dr Vladimir Pavlović Serbian Academy of Sciences and Arts, Institute of Technical Sciences Momčilo Ristić Serbian Academy of Sciences and Arts The aim of this work was to analyse the kinetics and microstructure evolution of ZnO sintering process. ZnO powder was isothermally sintered (15, 30, 60, 90 and 120 min) in the temperature range from 8000C to 12000C. The values of Lenel parameter were calculated and used for the analysis of the densification and mass transport processes. Using scanning electron microscopy the analysis of the microstructure evolution and dependence of the average grain size with temperature and time of sintering was obtained. The results of this research could enable development of a new phenomenological equations in the analyses of ZnO-based materials sintering kinetics.

Keywords: ZnO, Sintering, Kinetics.

INTRODUCTION Complex requirements in the synthesis of materials with pre-defined functional, physical, technological and exploitage properties are the result of the rapid development in modern technology [1]. Recently, special attention was paid to the research of the ways of synthesis and properties of multifunctional materials which are used in the production of new and/or technologically advanced equipment in different fields; from electronics to medicine [2].

In the group of metal-oxide materials zinc-oxide is abstracted as a material which has been for a very long time studied whether in form of a single crystal, polycrystalline powder, film or ceramic, and in recent years in various nanostructured forms [3]. Thanks to its exceptional physical and chemical properties, ZnO has a wide range of applications, from the production of pigment, rubber, composite materials, cosmetics and pharmaceutical creams for the protection from ultraviolet (UV) radiation or anti-bacterial effect to the production of piezoelectric converters,

optical wires, acoustic-wave devices, varistors, chemical and gas sensors, light emitters [4] and etc.

ZnO-based materials have been obtained by different physical and chemical methods, such as evaporation deposition, spray pyrolysis, a variety of aerosol and sol-gel techniques, ion implantation, laser ablation, etc. Using these methods significant success has been achieved recently in obtaining the various ZnO nanostructures with homogeneous and uniform particle size distribution. Sintering process has particularly important role in the synthesis of these materials. Sintering leads to shrinkage and reduce porosity which gives the possibility for obtaining materials with desired microstructural parameters [5]. Kinetics and mechanism of these macro changes have not yet been fully clarified even though the shrinkage during sintering is relatively easy to measure. Bearing all this in mind in this paper the kinetics of isothermal sintering and changes in morphology and microstructure of sintered ZnO were analyzed.

* Institute of Technical Sciences of the Serbian Academy of Sciences and Arts,Knez Mihailova 35/IV, 11000 Belgrade, Republic of Serbia; darko.kosanovic@itn.sanu.ac.rs

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Darko Kosanović and etc. - Microstructure evolution and sintering kinetics of Zno

EXPERIMENTAL PROCEDURE For the experimental study in this paper commercial ZnO powder (Kemika-Zagreb, and 99%, Mr = 81.37) was used. The powder was compacted in double steel mold with diameter of 8 mm. In our research the two-sided pressing of 1 t/cm2 (98 MPa) was used.

Sintering of ZnO green samples was carried out in a laboratory chamber furnace. Green samples were directly pulled in a preheated oven at 800, 900, 1000, 1100 and 12000C and then rapidly cooled and extracted after 15, 30, 60, 90 and 120 min.

Scanning electron microscope was used to investigate the microstructural properties of ZnO sintered samples.

RESULTS AND DISCUSSION One of the most important technological processes, used for the synthesis of modern materials that provides the possibility of obtaining materials with pre-defined properties, is certainly the process of sintering [6]. In this study, we analyzed the kinetics of ZnO isothermal sintering by monitoring the changes of Lenel parameter, morphology and microstructural characteristics of sintered samples and the dependence of average grain size of ZnO with the temperature and sintering time.

Analysis of the densification process, in other words the reduction of pore volume, usually has a phenomenological character, but based on the obtained relations, using different models, some information on the mechanism of mass transport that are essential to the process of sintering could be obtained. The course of densification could be characterized using the changes in relative density, porosity, volume and linear shrinkage or through some of the relations that connect the initial, sintered and theoretical density [7]. In this work the changes of relative density and porosity were investigated.

Theoretical density (TG) of ZnO is ρT = 5,657g/ cm3, while the densities of the sintered samples (ρs) were determined based on the measurenents of the mass (ms) and sample dimensions: height (h) and diameter (D), a relative density of sintered samples were determined as a ratio between theoretic and measured density values (ρs) and (ρT), as shown in Table 1.

The analysis of the results given in Table 1, clearly have shown that the values of the relative densities of sintered ZnO samples increased with the temperature and the time of sintering.

Maximum values are obtained for ZnO samples activated for 90 and 120 minutes and sintered at 1100oC. Based on our previous investigations, prolonged milling times can cause formation of agglomerates that can prevent sintering process at high temperatures.

Table 1. Relative densities of ZnO sintered samples expressed in (%)TG. T(0C)

Time (min) 15

30

60

90

120

800

71,68

72,51

74,61

75,05

76,31

900

82,73

83,33

84,20

84,33

84,58

1000

86,62

86,95

88,19

89,27

89,66

1100

91,23

91,79

92,36

93,19

93,58

1200

91,67

91,78

92,75

92,98

92,98

The degree of densification during sintering is usually characterized with Lenel parameter, L [8], which describes a simple relation between the sintered PS and the initial porosity P0 i.e. theoretical ρT, sintered ρS and initial ρ0 density of the samples: (1) The usage of Lenel parameter, the variable dependent with temperature and sintering time, in

318

our analysis, was conditioned by the fact that it is connected with simple relations to the other parameters used in such investigations, that simplifies the comparison of the results.

A mathematical analysis of the obtained experimental values of Lanel parameter was performed with sufficient accuracy by fitting the results with the equation: (2) Journal of Applied Engineering Science 9(2011)2, 197

Darko Kosanović and etc. - Microstructure evolution and sintering kinetics of Zno

L0, A and n are constants, t is time of sintering. L0 corresponds to the value of Lanel parameter at the beginning of isothermal sintering, therefore it represents the degree of densification at the beginning of isothermal heating regime. The calculated values of Lenel parameter for the sintered samples at different temperatures during isothermal sintering, are graphically presented in Fig. 1.

From obtained results for L0 can be seen to be increasing with temperatures up to 11000C, which indicates that at a given mode the system enters the final stage of sintering, in which the density approaches its maximum (relative density of these samples is about 95%), as shown in Table 2.

Figure 1. Changes of Lenel parameter during ZnO isothermal sintering.

Table 2. Values of L0, A and n parameters at different temperatures obtained by fitting.

T(0C) Parameters

800

900

1000

1100

1200

L0

0,259

0,580

0,663

0,760

0,682

A

0,031

0,012

0,004

0,013

0,088

n

0,383

0,563

0,654

0,405

0,124

The other two parameters A and n that characterize, in fact, the rate of the densification process during sintering, have a little more complexed dependence with temperature.

The parameter n is increased to temperature of 10000C, which affects the increase in density, while lowering the temperature parameter A points to the the initial stage of sintering is still present (Tab.2).

the process of mass transport during sintering of ZnO was intensified in the temperature range 800-10000C, which certainly had to do with the system’s increased activity due to its higher porosity at lower temperatures.

Scanning electron micrograph of the initial ZnO powder is shown in Fig. 2. It indicated the uniform distribution of particles and their polygonal shape.

On the basis of this it could be concluded that Journal of Applied Engineering Science 9(2011)2, 197

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Darko Kosanović and etc. - Microstructure evolution and sintering kinetics of Zno

and that the process of grain growth was intensified. It was found that large grains retained their polygonal shape which led to their merger, while the mass transport through the contact zone and surface diffusion was dominant in the smaller grains. Increasing sintering time intensified the process of mass transport and grain polygonisation. Increased sintering temperature led to the grain growth and caused the formation of irregularly shaped, closed pores, clearly seen in Figure 3.b.

Figure 2. SEM of ZnO initial powder.

Figure 3. shows the micrographs of samples sintered for 90 min at different temperatures. SEM micrograph of sample sintered at 8000C (Fig. 3.a) shown that the microstructure of this sample was characterized by large, open porosity and inhomogeneity, which is in accordance with the principles of the recrystallization and grain growth theory [9], present within initial sintering stage.

The grains with irregular polygonal shapes were observed as well. It may be noticed that some grains were consisted of a number of particles

Figure 3a. SEM of ZnO sintered for 90 min at 800 0C

320

0

Figure 3b. SEM of ZnO sintered for 90 min at 1000 C

0

Figure 3c. SEM of ZnO sintered for 90 min at 1100 C

Journal of Applied Engineering Science 9(2011)2, 197

Darko Kosanović and etc. - Microstructure evolution and sintering kinetics of Zno

Sintering at 11000C, presented in Figure 3. c. led to anisotropic grain growth and mass transport which consequently created spheroide, closed pores, characteristic for final sintering stage. The microstructure of samples sintered at 12000C was not much different from the microstructures of the samples sintered at 11000C (the calculated densities indicated this as well), but the uniform grain growth and the disappearance of open porosity was still noticed.

Fig. 4. shows the dependence of average grain size G of ZnO with the temperature and time of sintering. This diagram shows that after sintering at 1000, 1100 and 12000C the grains remain approximately with same size, but with increasing sintering temperature, up to 12000C (more than 60 minutes), leads to further grain growth.

0

Figure 3d. SEM of ZnO sintered for 90 min at 1200 C

Figure 4. The dependency of the grain size of ZnO with the temperature and time of sintering.

CONCLUSION In this work we analyzed the kinetics of sintering and changes in the microstructure of sintered ZnO. It was also found that the initial sintering process is characterized by intensive mass transport during sintering of ZnO in the tempera-

Journal of Applied Engineering Science 9(2011)2, 197

ture range from 8000C to 10000C, which certainly had to do with the system’s activity due to its higher porosity at lower temperatures. Based on the experimental results the values of Lanel parameter were determined and it was found that it reaches its maximum values for samples activated for 90 and 120 min and sintered at

321

Darko Kosanović and etc. - Microstructure evolution and sintering kinetics of Zno

11000C, indicated the final sintering stage.

SEM analysis determined a balanced densification of the material with the increase of sintering temperature, as well as the pore spheroidization and reduction. It was noted that the system entered the final stage of sintering at temperatures above 11000C, while the grains were in uniform polygonal shape. The results of these research is a contribution to the existing investigations of the ZnO-based materials sintering kinetics.

ACKNOWLEDGEMENT This research was a part of projects: 142011G, financed by the Ministry of Science and Technological Development of the Republic of Serbia and Ф-7 financed by the Serbian Academy of Sciences and Arts.

RERERENCES 1) Minić V. M., (1998) Dijagrami sinterovanja oksida cinka i kadmijuma, Magistarska teza, Univerzitet u Beogradu 2) Brown E. H., (1976) Zinc oxide: Properties and application, Pergamon pres, New York.

3) Klingshirn C., (2007) ZnO: Material, Physics and Applications, ChemPhysChem.

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4) Ristić M. M. (1993) Principi nauke o materijalima, SANU, Beograd.

5) Ristić M. M., Pryadko L. F., Kunicki Ja. A., Nikolić Z. S., Živković M. M., Radić S. M. (1996) Prognoza fizičkohemijskih svojstava materijala, CMS, Beograd 6) Ивенсен В. А., (1985) Феноменология спекания и некоторые вопросы теории, Металлургия, Москва.

7) Lee W. S., Chen W. T., Lee Y. C., Yang T., Su C. Y., Hu C. L., (2007) Influence of sintering on microstructure and electrical properties of ZnO-based multilayer varistor (MLV), Ceram.

Int., 33, 1001-1005.

8) Exner H. E., (1979) Principles of Single Phase Sintering, in Reviews on Powder Metallurgy and Physical Ceramics, Edited by Fritz V. Lenel, Freund Publishing H o u s e LTD, Tel-Aviv. Israel.

9) Ristić M.M., Maričić A. M., Kosanović D.A., (2009). Rekristalizacija i rast zrna, ITN-SANU i TFČ Čačak, Čačak.

Paper sent to revision: 17.02.2011.

Paper ready for publication: 21.04.2011.

Journal of Applied Engineering Science 9(2011)2, 197

Paper number: 9(2011)2,198, 323 - 330

AGRICULTURAL TRACTOR CAB CHARACTERISTICS RELEVANT FOR MICROCLIMATIC CONDITIONS Mr Dragan Ružić* University of Novi Sad, Faculty of Technical Science Dr Ferenc Časnji University of Novi Sad, Faculty of Technical Science

The basic purposes of an agricultural tractor cab are to provide comfortable environment for an operator and to protect him from vibrations, noise and other adverse influences. The microclimatic features of middle-sized tractor cabs are the focus of this paper. The microclimatic conditions are related with design features that influence heat processes between the cab and the environment, including the effects on the operator.

One of methods for improvement of the microclimatic conditions and for reducing of air-conditioning energy consumption is prevention of cab heat gain, achieving this by appropriate heat rejection and insulation. Since the cab material characteristics and cab design play the main role in the heat transfer processes between the cab and the environment, these features are analyzed on existing middle-sized tractor’s cabs. The aim of the paper is to identify and evaluate most important influences, in order to create the basis for microclimatic and energy consumption reduction aspects of a tractor cab design. The results showed that the cab glazing is probably the most influencing factor, where the selection of the appropriate properties could be the way for cab and operator heat load reduction.

Key words: Tractor, Cab, Ergonomics, Microclimate, Glass INTRODUCTION Modern agricultural tractors are complex and highly-efficient systems, whose development is constantly directed towards reduction of negative impact on the environment (higher fuel efficiency and lower pollution, less soil compaction, to mention a few), but also towards operator’s space ergonomics. Conditions inside the cab have significant impact on operator performance, therefore on total result in the man-tractor-environment system too. From the operator’s point of view, cab ergonomic is a key factor in ensuring of his optimum working performance, which could easily become the weakest link in the working process. While, on the one hand, the cab offers the mechanical protection and protection from adverse ambient conditions, on the other hand, even under moderate outside conditions the closed cab act like green house and its closed interior could become unpleasant, unbearable and even dangerous.

This paper covers designing aspects of tractor cab that have direct or indirect effect on ergonomics of the thermal environment on operator’s working place. Ergonomics of the thermal environment is based on the relationship among air temperature, interior surfaces radiant temperature, air velocity and relative humidity, which in combination should obtain the absence of discomfort, for given operator’s activity and clothing [6], [15].

Thermal processes in cab system are almost independent from tractor’s working operation, in contrast to noise and vibration, but are depending on outside thermal conditions (air temperature, air velocity, intensity of solar radiation).

Therefore, the cab is here taken as a separate unit. Since decreasing the heat gain of the cab means also reduction of thermal load to the operator, relevant design parameters are analyzed in this paper. The aim of the paper is to identify most influencing factors in order to consider pos-

* Faculty of Technical Sciences, Trg D. Obradovića 6, 21000 Novi Sad; ruzic@uns.ac.rs

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Mr Dragan Ružić and etc. - Agricultural tractor cab characteristics relevant for microclimatic conditions

sibility for improvement of the microclimatic design aspects of agricultural tractor cab.

MAIN DESIGN FEATURES OF TRACTOR CABS RELATED TO THERMAL LOAD Brief overview of the design features related to the thermal processes and HVAC characteristics was made, based on the available documentation and by inspection of the agricultural tractors that are present on local market. The analysis involved 26 different cabs that are installed on 90 models made by 11 tractor manufacturers. Orchard and vineyard tractors (narrow track tractors) were not included into the analysis. All tractors from the sample are 4WD wheeled tractors, with power ranging from 40.5 to 155 kW, weight ranging from 2750 to 8410 kg and wheelbase ranging from 2.055 to 3.089 m.

Main outer cab dimensions are evaluated from 9 different cab data, which are installed on 29 models of tractors made by 5 tractor manufacturers. These tractors are powered by 54.5 – 118 kW rated diesel engines, weighting from 3330 to 6555 kg and with wheelbases ranging 2.316 – 2.800 m. Cab outer lengths are from 1.40 to 1.77 m, cab widths are from 1.38 to 1.70 m, and cab heights are from 1.45 to 1.80 m. The dimensions of the cabs meet relevant standards ([14], [20], [21]). Correlations between basic tractor design features and cab dimensions are given in Table 1. It can be seen that the cab length has the largest correlation coefficient with wheelbase, the cab width has the largest correlation coefficient with engine power and the cab height has no significant correlation with any of the parameters.

Table 1. Correlation coefficients between basic tractor design parameters and cab dimensions Correlation Cab length Cab width coefficients

Cab height

Engine rated power

0.234

0.503

0.197

Tractor weight

0.366

0.741

-0.032

Tractor wheelbase

0.498

0.420

0.041

from 150 to 250 kg.

Basic materials for cab frame are steel profiles, taking in account demands for mechanical protection of an operator. Cab frames mostly have six pillars, although there are designs with four pillars [14]. In order to provide the best visibility from the operator seat (according to [23]), vision obstructing elements need to be minimized, which is in contrast to the requirement for high mechanical strength of the cab structure. For that reason, main and the thickest pillars are usually placed in the rear part of the cab, behind of main field of the vision. Cab roof is made of polymers and contains the ventilation air distribution system, as well as evaporator and blower of air-conditioner.

The cab glazing (excluding the roof window) in modern tractors are approximately 60% of total cab surface area. Glass is generally tempered and tinted.

All cabs have air distribution system with outlets placed on the ceiling (top air distribution system).

Cabs of larger tractors from the sample have also outlets on the instrument panel (front air distribution systems). Additional air distribution system placed laterally can be seen rarely, only in top-class tractors. The air outlets (nozzles) on the ceiling can have symmetrical or asymmetrical layout, while the nozzles on the instrument panel always have symmetrical layout. Nozzles have mostly circular cross-section and air jet direction could be changed by the operator.

Automotive vapour compression closed systems are used for air-conditioning (AC). Installed compressors could take around 4 – 6 kW from the tractor engine, which presents 2.5 - 15% of the rated power in this tractor category.

DESIGN PARAMETERS RELATED TO THE HEAT EXCHANGE BETWEEN THE CAB AND THE ENVIRONMENT The analysis of thermal characteristics of the cabs was done for adverse environmental conditions that can be encountered in the local region [7], [18]: •

The weights of the cabs are determined as a difference of the tractor weights with and without cab. The data were available for 6 cabs of 3 tractor manufacturers and cab weight is ranging

324

• •

maximum outdoor air temperature greater than 30°C, total solar irradiation on outer surfaces up to 1000 W/m2, prolonged periods of unchanged tractor poJournal of Applied Engineering Science 9(2011)2, 198

Mr Dragan Ružić and etc. - Agricultural tractor cab characteristics relevant for microclimatic conditions

sition related to the sun, over the flat landscape without shade, • closed cab because of protection from noise and air pollution, • low tractor velocity that limits the natural cab ventilation.

• Sum of cab heat gain in hot environment under the steady-state conditions, without sensible QH and latent heat QHw released by the operator, is consisted of (Fig. 1.): • heat transfer through the cab envelope due to temperature difference Qk, • heat transfer through the cab roof caused by the solar radiation Qsun, • solar radiation transmission through the glazing QGsun, • heat gain from the powertrain QPT. In order to maintain interior temperature constant, heat release by the air-conditioning QAC should be equal to the heat gain. According to the requirements for thermal comfort in summer conditions, interior air temperature should be in range of 23 to 28°C, combined with adequate local air velocities [16], [17].

neglected, because of complexity and relatively small surface temperature difference.

Heat transfer through the cab walls due to temperature difference Assuming that temperature in vicinity of the walls are uniform on inner as well as outer side, onedimensional heat flow through this part of cab walls is (Fig 2):

Figure 2. Heat transfer through the cab wall due to air temperature difference.

Parameter U is total heat transfer coefficient which combines convections from each side of the wall and conduction. General equation for a wall of area Aj with number of layers equal to m is:

For all surfaces with the heat transfer due to air temperature difference, the total value of U is: Figure 1. Thermal processes between a tractor cab and hot environment.

For the analytical investigation of influencing parameters, it was assumed that the heat flow is one-dimensional steady flow through a plane wall with natural convection on both sides. Radiant heat exchanges among inner surfaces are Journal of Applied Engineering Science 9(2011)2, 198

This value is dependent on wall layer material thermal characteristics (thermal conductivity k, W/mK), layer thickness and their areas. The

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Mr Dragan Ružić and etc. - Agricultural tractor cab characteristics relevant for microclimatic conditions

surfaces where this mode of heat transfer takes place are surfaces that are not exposed to the solar radiation neither radiation from the powertrain. For example, these surfaces are windows on the shaded side of the cab. Therefore, main factors for this mode of heat transfer are dependent on glass thermal characteristics, the glass area and thickness.

Based on very limited sources, it is assumed that for cab of standing vehicle U = 3 ÷ 8 W/m2K [1], [11], [22]. For chosen outside-inside air temperature difference equal to 36° – 23° = 13°C, heat flux through the cab wall qk would be in the range of 40 – 100 W/m2.

Heat transfer through the cab roof caused by the solar radiation Caused by absorbed part of the solar irradiation, cab outer surface is heated and its temperature is increased. Maximum solar irradiation on horizontal surface (roof) on a summer day in the central region of Vojvodina may exceed 900 W/m2 [7]. After the certain time of exposure to the sun radiation, the heat gain by the radiation and heat release reach the thermal equilibrium. From the outer surface heat is released by longwave radiation to the environment (mostly to the sky) and by convection to the colder surrounding air. Part of the heat passes through the wall, heats the material up and being released to the colder interior air by convection and emitted by the longwave radiation. Cab surfaces involved in this part of heat process are roof, pillars and glasses exposed to the sun (Fig. 3.). Cab glazing will be analyzed in the part of the paper that deals with transmission of thermal radiation through the glass.

Figure 3. Heat transfer through the cab roof caused by the solar radiation.

326

Cab roof is generally hollow and contains ventilation and AC components, so heat transfer from hot outer surface is not direct, but through the air space. For that reason, such roof is not very critical from the solar radiation problems, as single wall roof (or such part of the roof) is. Inside the hollow roof, heated outer layer transmits energy to the air and radiate to the inner layer. Inner layer receive the thermal energy and transmits it to the cab interior. Similar situation is valid for pillars too, since the pillars are made from hollow steel profiles. In contrast to the roof, steel pillars present a thermal bridge to the cab interior due to higher thermal conductivity of the steel, unless some kind of upholstery is used on the inner side of the pillar.

Thermal balance equation for outer surface of the roof can be written as:

while the thermal balance on the inner roof surface is:

Heat radiation of warm wall has direct influence on an operator, and it is depending on wall surface temperature and wall’s emissivity, which is generally high for non-metallic surfaces (larger than 0.9 [8]). Using an example of heat flux assessment for the opaque roof, treating the roof as a single layer wall, design parameters will be discussed. Hence, equation of heat flux that flows through the roof, caused by solar radiation, is:

For selected thermal properties of the roof material, its thickness and for 900 W/m2 of solar irradiation on horizontal surface with solar absorption coefficient of 0.3 (Table 2.), calculated heat flux through the roof was greater than 40 W/m2. This presents at least 15% of total radiation on the surface, assuming that the AC keeps interior air temperature on level of 23°C. Using Journal of Applied Engineering Science 9(2011)2, 198

Mr Dragan Ružić and etc. - Agricultural tractor cab characteristics relevant for microclimatic conditions

the iterative method for outside and inside roof surface temperatures calculation, interior surface temperature was estimated on more than 50°C. Large uncertainty for analytical determination of the heat flux was caused by calculation of the convection coefficients, which could differ according to the various sources [2], [4], [8].

Consequently, the most influencing factors are solar absorptivity and longwave emissivity of the roof material, then its thickness and conductivity. Therefore, outer roof surface should have low solar absorptivity coefficient and high emissivity (small αs / ε ratio is preferable [8]), with low ther-

mal conductivity in the same time. Although, in order to reduce thermal radiation towards operator’s body surface, interior roof surface should have low thermal emissivity.

Thermal properties of materials are given in Table 2. Solar absorptivity is depending also on surface colour [1], [8]. From this point of view, more preferable are light colours, which are widely used for tractor roofs. Despite the high thermal conductivity, one of most popular material for reflection of thermal radiation is aluminium (αs = 0.09 – 0.15 [8]), but it is not utilized for these purposes in tractor cab design.

Table 2. Thermal characteristics of cab materials

plastic, white tempered single glass, clear tempered single glass, green tinted metal, painted white metal, painted black

solar absorptivity, αs 0.23 – 0.49 [2], 0.08 [19] 0.45 [19]

0.21 – 0.25 [1], [8], [11] 0.80 [11]

surface emissivity, ε 0.90 – 0.97 [2], [8], [11] 0.8 – 0.95 [1], [2], [8], [11] 0.8 – 0.95 [1], [2], [8], [11]

thermal conductivity, normal solar k (W/mK) transmissivity, τ 0.12 /11/ 0.8 [19] 0.8 [19]

0.85 -0.96 [1], [8], 40 – 45 [11], [12] [11] 0.97 [1], [8], [11] 40 – 45 [11], [12]

Cab glazing is semitransparent medium where solar irradiation can be partially reflected, absorbed and transmitted, Fig. 4.

Solar irradiation on a cab surface is variable because of sun position as well as orientation of the cab surfaces. Maximum (“clear sky”) intensity of

0.84 – 0.90 [1], [19] 0.49 [19]

-

normal irradiation and its variations in time and due to various positioning of the cab surfaces are showed on Fig. 5 and Fig. 6, for vertical surface and for 20° inclined surface, respectively.

Heat transmitted through the glass exposed to the solar radiation is:

As can be seen, absorbed part of the solar energy will be emitted to the cab interior by both convection and longwave radiation. Using available values of glass properties (Table 2) with solar irradiation on inclined glass equal to 876 W/m2 (west-faced glass, afternoon, Fig. 2), estimated total heat flux will be around 760 W/m2 for clear, and less than 500 W/m2 for tinted glass (green, with 75% transmittance of visible light /19/).

Figure 4. Solar energy transmission through the glass Journal of Applied Engineering Science 9(2011)2, 198

Within the sample of tractors, windshield inclination is in range of 8 – 20° and side windows in-

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Mr Dragan Ružić and etc. - Agricultural tractor cab characteristics relevant for microclimatic conditions

clination is in range of 7 – 10°. According to the Fig. 5 and Fig. 6, the vertically positioned glass receives around 16% less solar irradiation than the glass inclined at an angle 20°.

Total amount of heat transmitted through the glass caused by solar radiation is related with cab surface projection normal to the radiation direction. Since maximum solar transmissivity of the glass is in region of incident angles less than 30°, areas that are directed within this angle to the radiation direction are critical, for two reasons. First, because of maximum solar radiation transmittance to the cab interior, and second because of direct effect on the operator, increasing his skin temperature and hence producing the discomfort.

tractors partly “protrude” in the cab space, while larger tractors have a flat floor. For the purposes of sound and heat insulation, floor is generally multi-layer (rubber or polymer as interior flooring, steel sheet floor and in some designs, with a foam insulation material or composite heat shield on the powertrain side of the floor).

Figure 7. Heat gain from the powertrain

Figure 5. Global solar clear-sky irradiation Gs on a vertical plane for different orientation, in a central part of Vojvodina on a day in July [7]

In this case, heat transfer through the floor is modelled as a combination of radiation from hot powertrain surfaces and natural convection from hot surrounding air on the bottom side of the floor, Fig. 7. It was assumed that the air between the powertrain and the floor has a temperature of 80°C as well as powertrain outer surfaces (taken from service manual as maximal recommended transmission oil temperature). In addition to radiative properties and temperatures of the surfaces, geometry has also influence on heat exchange, which is included through a view factor.

Because of parallelism and small distance between the powertrain and the floor, it is assumed that view factor is equal to unity [8], [12]. Heat flux that floor absorbs from hot powertrain surface and surrounding air can be written as:

where /12/:

Figure 6. Global solar clear-sky irradiation Gs on a plane inclined at an angle 20° from vertical, for different orientation, in a central part of Vojvodina on a day in July [7]

Under the thermal equilibrium, the same amount of heat is transferred through the floor and transmitted to the interior air:

Heat gain from the powertrain Powertrain (transmission) is situated beneath the cab of typical tractors. Powertrain of smaller

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Mr Dragan Ružić and etc. - Agricultural tractor cab characteristics relevant for microclimatic conditions

The calculated value of heat flux through the cab floor caused by powertrain heat is greater than 120 W/m2, while interior floor surface temperatures would reach 50°C. With the outer insulation or heat shield, the heat flux would be halved, with the lower floor temperature.

Total thermal load of the tractor cab Total thermal load of the cab under chosen moderate summer conditions will be depending on the size of the cab and on its orientation in relation to the sun. Worst case from the heat gain and direct influence of the solar radiation on the operator could be the case when largest side of the cab is faced to the sun. Roughly, this could be approximately 1/4 of glazed area, e. g. around 1.5 m2, which gives solar heat load of order of 1100 W. Rest of area faced to the environment (app. 7 m2) would transfer up to 700 W of heat, and estimated heat gain from the powertrain would be 200 W. In total, without the heat released from the operator, estimated heat load of the cab is around 2 kW. CONCLUSIONS The cabs of the modern tractors have many common features, from the material to design, and can be stated that cabs have high level ergonomic characteristics. However, the possibility for implementation of solutions for further improvement of microclimatic conditions exists, especially within the lower range of analysed tractor category. Based on presented simplified calculations, the principal conclusions may be summarized as follows: •

General cab design tendency is towards larger cabs, in addition to fact that larger tractors have larger cab too. Larger cab means more volume and mass to cool, but obviously the spacious and comfortable working space for an operator has priority. Therefore, increasing in the cab size does not mean such considerable increase in the cab thermal load.

•

Most intensive heat flux that enters the cab is caused by solar radiation through the glass (5 to 10 times more than by other analysed modes of heat transfer). Less inclined glasses and solar radiation selective glasses offers possibilities for solar load reduction. In comparison to solar absorbing glasses (such tinted glasses are), better but more expen-

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sive solution would be infra-red reflective glass that rejects almost half of solar radiation energy with less obstruction of visible light transmission. Also, overhangs of the roof could help in reduction of glass area exposed to the strong solar radiation around the noon time.

•

Heat shield made from reflective material placed on the bottom side of the cab could minimize the powertrain radiant heat effect on the cab floor.

•

Due to significant variations among many coefficients, experimentally validated numerical methods are recommended for calculation of thermal loads, optimization of cab shape, choice of the materials and design of the air distribution system.

ACKNOWLEDGMENT This research was done as a part of project TR31046 “Improvement of the quality of tractors and mobile systems with the aim of increasing competitiveness and preserving soil and environment”, supported by Serbian Ministry of Science and Technological Development.

NOMENCLATURE AGs – area of glass exposed to the solar radiation, (m2) Ak – area of cab outer surface with conductive heat transfer, (m2) As – area of cab outer surface exposed to the solar radiation, (m2) Gs – total solar irradiation, (W/m2) hc – convection heat transfer coefficient, (W/ m2K) k – thermal conductivity, (W/mK) Qc – heat transfer by convection, (W) qsun – heat flux caused by solar radiation, (W/ m2) Qk – heat transfer through the wall, (W) qPT – heat flux gained form powertrain, (W/m2) ta, Ta – air temperature, (°C, K) Tsky – apparent sky temperature, (K) /1/ α – surface absorptivity, (-) αs – surface solar absorptivity, (-) δ – layer thickness, (m)

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ε – surface emissivity, (-) σ – Stefan-Boltzmann constant (5.670•10-8 W/ m2K4) θ – incident angle of solar radiation, τ – normal solar transmittance, (-) Indexes floor – cab floor material or surface G – cab glazing i – internal, inside the cab o – outer roof –cab roof material or surface REFERENCES 1) ASHRAE Applications Handbook (1999).

Chapter 32 – Solar Energy Use, ASHRAE 2) ASHRAE Fundamentals Handbook (1997).

Chapter 3 – Heat transfer, ASHRAE 3) Bohm M., Holmer I., Nilsson H., Noren O. (2002). Thermal effects of glazing in driver’s cabs, JTI-rapport, 2002

ing Demand in a Truck Compartment, Master thesis, Uppsala Universitet 12) Kozić, Đ., Vasiljević B., Bekavac V. (1994).

Priručnik za termodinamiku, Beograd: Univerzitet u Beogradu, Mašinski fakultet 13) Mc Adams, W. (1969). Prostiranje toplote, Beograd: Građevinska knjiga 14) Mitić, S. (2004). Uticaj zaštitnih struktura traktora na povećanje bezbednosti rukovalaca u eksploataciji, Istraživanja i projektovanja za privredu (4, 5), 41 – 49.

15) Parsons K. (2003). Human thermal environments: The effects of hot, moderate and cold environments on human health, comfort and performance, 2nd ed. Taylor & Francis, London 16) Ružić D, Časnji F (2011). Personalized ventilation concept in mobile machinery cab, International Journal for Vehicle Mechanics, Engines and Transportation Systems, 1(37), 7 – 22.

4) Conceicao, E., Silva, M., Andre J., Viegas.

(1998). A Computational Model to Simulate the Thermal Behavior of the Passengers Compartment of Vehicle, SAE Paper 199901-0778

17) Ružić, D. (2010). Improvement of thermal comfort in a passenger car by localized air distribution, 11th International Symposium “Interdisciplinary Regional Research ISIRR 2010”, Szeged 13-15 October, Abstracts, 210 – 210.

5) Časnji, F., Ružić, D., Muzikravić, V., Poznanović, N., Stojić, B. (2003) Ergonomske karakteristike savremenih traktora snage 60-120 kW, Traktori i pogonske mašine, 8(4), 7 - 12.

18) Ružić, D., Časnji F., Muzikravić V. (2007).

Karakteristike stakla kao faktor od uticaja na mikroklimu u traktorskoj kabini, Traktori i pogonske mašine, 4(12), 92 – 97.

6) Fanger P. O. (1970) Thermal comfort, New York: McGraw-Hill 7) http://re.jrc.ec.europa.eu/pvgis/apps3/pvest. php, retrieved on April 2011 8) Incropera F. P., DeWitt D. P. (1981). Fundamentals of heat and mass transfer, New York: John Wiley & Sons 9) Jahns G. von, Janssen J. (1982) Klimatizierung von Fahrerkabinen landwirtschaftlicher Fahrzeuge, Grundl. Landtechnik 32, 164 – 171.

10) Janssen J. (1984). Luftführung in Fahrerkabinen unter dem Gesichtspunkt der thermischen Behaglichkeit, Grundl. Landtechnik 34 (5), 198 - 205.

19) Saint-Gobain Sekurit, Glazing Manual, 2003 20) SRPS ISO 4252 (1997). Agricultural tractors – Operator’s workplace, access and exit - Dimensions 21) SRPS M.L2.156 (1994). Agricultural and forestry wheeled tractors – Operating space 22) Tavast, J. (2007). Solar Control Glazing for Trucks, Master thesis, Uppsala Universitet 23) UN ECE Regulation No. 71 (1987) – Driver’s field of vision of agricultural tractors, Geneva: United Nations Paper sent to revision: 11.05.2011.

Paper ready for publication: 03.06.2011.

11) Karlsson, Anika (2007). Simulation of Cool-

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Paper number: 9(2011)2,199, 331 - 338

CONCEPT MODEL AND THE SYSTEM OF SUPPLY AND MANAGEMENT OF BIOMASS Dr Dragiša Tolmač * University of Novi Sad, Technical faculty „Mihajlo Pupin“, Zrenjanin Dr Slavica Prvulović University of Novi Sad, Technical faculty „Mihajlo Pupin“, Zrenjanin Mr Ljubiša Josimović Technical school, Požarevac Dragana Dimitrijević University of Novi Sad, Technical faculty „Mihajlo Pupin“, Zrenjanin The biomass supply chain constitutes a system that is highly dynamic. The developed and proposed systems architectures for the management of the supply chains of typical industrial products do not directly apply to the case of the biomass supply chain. Nevertheless, it is imperative that a dedicated framework is needed according to the industrial standards. In this paper, a framework for the biomass Concept Model and the System of Supply and Management of Biomass (CMSB) supporting the efficient management of organizational events within the examined supply chain is proposed and analyzed. The conceptual model includes the identification and specification of events and the preparation of necessary notification based on information needs. On this basis, the paper presents the following relevant elements: Overview of existing literature on the system CMSB, supply chain networks and biomass, the concept of supply chain management system, the types of events that occur in the supply chain of biomass, the concept of supply and management of biomass.

Keywords: Model, Concept, Management, Bioenergy, Biomass INTRODUCTION Biomass has been recognized as one of the most promising renewable energy sources in the near to mid-term perspective. The biomass supply chain is characterised by a number of special characteristics and thus, it is not adequate to analyse it in the same way as a general supply chain, Figure 1. In the case of the traditionally biomass supply chain aimed at producing ethanol and biodiesel, i.e. corn, and soybean, the special characteristics include: - Long distance transportation. It must adhere to the economies of scale and be cost effective in terms of facility sizing and thus requiring a large arable area dedicated to “raw material supply”.

This characteristic increases the need for long distance transportation. Furthermore, due to the wide spatial distribution of the fields that constitute this area, the transportation will have to take place through a complicated public as well as rural road network.

•

High inventory cost. Although bioenergy is used all year around, the “raw material” is produced once a year.

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Short operational time window. The short harvesting time window is caused by the time- sensitive crop maturity. Furthermore, these operations have to be carried out within a short time-window using resources also necessary for other concurrent field operations.

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Weather dependency. The weather conditions are a restrictive factor in terms of the available time period for the execution of the operation and thus can create variations in time, cost and equipment for the scheduled procedure. For example, if harvest conditions regarding crop maturity are poor, the moisture of harvested material may be more than the permissible moisture content for longterm storage and a drying process should be added to the total procedure.

* Technical faculty „Mihajlo Pupin“, Đure Đakovića bb, 23000 Zrenjanin; dtolmac@sbb.rs

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•

Land availability restriction. Since there is an upper limit associated with the land available for the cultivation of the “raw material”, the market prices is highly connected to the demand, and thus the increase or decrease of the demand will subsequently increase or decrease its price.

•

Sustainability aspects. The soil must be in a condition suitable for the machinery to operate minimising damage to the soil. Soil condition depends upon soil type, crop type and current as well as recent weather conditions.

Figure 1. Supply chain networks and biomass

It is estimated that about 20–40% of the cost of ethanol is related to the biomass supply chain, while about 90% of that cost is logistics related cost (Reynolds, 2002). In order to partiallyovercome the uncertainty imposed by the above mentioned factors, research studies are considering as an alternative the use of ligno-cellulosic biomass to produce bioenergy. Ligno-cellulosic biomass includes by-products from forestry and agriculture, referred to as biomass waste (e.g., residues from maintenance work in green parks, thinning wood, and straw from cereal farming), municipal solid waste, and perennial grasses (Aden et al., 2002). Potential benefits includes harvesting windows that differ across the different species which increase the annual use of the specialized field machinery reducing the fixed costs of harvesting and collecting biomass, less inventory of biomass due to the fact that biomass is supplied all year around. Furthermore, perennial grasses can grow in soils that are not

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suitable for grain production, and, finally, using a variety of perennial species enables a diversified landscape and reduces the potential for insect and disease risk inherent with monocultures (Eksioglu et al., 2009). Also, solid waste as a “raw material” for bioenergy production include waste from household and industry (food, paper, demolition wood, and saw dust) which is available at a low cost.

Although that a vast amount of literature exists in the area of supply-chain design and logistics management for industrial products, the previously described special characteristics of the biomass supply chain determine that the biomass flow within a network cannot be considered in the same way as the flow of, e.g., heat, electricity, and gas. As a result, a number of dedicated optimisation models related to biomass supply network have been presented. Following some selected examples from the recent literature. (Frombo et al., 2009) developed a decision support system based on geographic information systems (GIS) and involving a non-linear mixed-integer programming for the optimal planning of forest biomass use for energy production. (Rentizelas et al., 2009) analyzed logistic issues of biomass related to the storage problem and the advantages a multi-biomass supply chain might have on the logistic cost. (Sokhansanj et al., 2006) presented a dynamic simulation program for collection and transportation of large quantities of biomass, which considers time-dependent availability of biomass under the influence of weather conditions and predicts the number and size of equipment needed to meet a certain demand.

The delivered cost of biomass was calculated based on the utilization rate of the machines and storage spaces. (Freppaz et al., 2004) presented a non-linear decision support model which considers the optimal exploitation of biomass resources with several dispersed harvesting sites and a number of centralized combustion plants on a regional level aiming to find the optimal capacity of heat and power generation as well as the optimal utilization of biomass resources and transport options in a time horizon of one year.

(Dyken et al., 2010) presented a linear mixed-integer modelling framework that can be applied to components in a biomass supply chain, including sources, handling/processing, storage and end use.

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prehensive research have been conducted on the adaptation and implementation of formalised planning tools and methods from the industrial domain in planning and scheduling of the field operations constituting the first link of the supply chain and involving the primary production of the material (biomass) that connects to the rest more industrialised links. (Bocthis et al., 2010), evaluated the functionalities, feasibility and longterm perspectives of implementing a modelling suite for determining the optimal time for initiating various operations related to the harvesting and treatment of grass forage based on moisture content predictions. (Basnet et al., 2006) presented an approach aimed at the scheduling of crop harvesting in multi-farms operations. (Guan et al., 2008) introduced Hybrid Petri nets into the modelling of farm work flows in agricultural production. This latter procedure is based on the fundamental that agricultural operations involve both continuous and discrete events. By usingappropriate abstracted representations of field operations planning problems, (Bochtis and Sorensen, 2009) and (Bochtis and Sorensen, 2010) developed a methodology for casting these planning problems as instances of the well known combinatorial optimisation problem, the Vehicle Routing Problem (VRP). (Sorensen and Bochtis, 2009) developed a conceptual model based on participatory approach for the fleet management of agricultural vehicles.

From the literature dedicated to the biomass supply chain, it is clear that the biomass supply chain constitutes a system that is highly dynamic and stochastic. The developed and proposed systems architectures for the management of the supply chains of typical industrial products do not directly apply to the case of the biomass supply chain. Nevertheless, a dedicated framework is needed according to the industrial standards, (Prvulovic et al., 2008).

This paper proposes a framework for the Concept model and the system of supply and management of biomass (CMSB) supporting the efficient management of inter-organizational events within the examined supply chain. The developed conceptual model will support the identification and specification of events and for the preparation of necessary notification based on information needs, (Prvulovic et al., 2009).

The paper is organized as follows: in the first section, the concept of CMSB is examined from Journal of Applied Engineering Science 9(2011)2, 199

the biomass supply chain perspective. The identification and categorization of the analogous events are the main objectives of the second section. Furthermore, the main requirements of a CMSB generic conceptual model are presented. These requirements will help the design of the proposed model.

MATERIAL AND METHOD The concept of supply chain management system During the last decade, an increasing focus for the CMSB has been observed. (Moreover, as Zimmermann, 2006) argued this has been addressed also by a large number of available CMSB systems in the IT market. Generally speaking, the main objective of a CMSB system is to introduce a control mechanism for managing events, in particular, exceptions, and responding to them dynamically (Meydanoglu, 2009). An event is just a signal that the internal data of a system which are being monitored has changed.

In case of the CMSB systems, the event is any individual outcome of a supply chain cycle, logistics process, activity, or task (Alvarenga and Schoenthaler, 2003). Enterprise information systems already generate events, if only for their own internal use. Events can originate from various sources, including logistics information systems and applications, data flow over a messaging platform, database updates, and messages from typical web applications.

The following table synthesises the existed literature defining the CMSB systems and presenting their main characteristics, Table 1.

It is possible to examine and evaluate the CMSB systems by three perspectives; a conceptual, a technical, and a business point of view.

From a conceptual point of view, a CMSB system is subdivided into the following five core aspects (Knickle and Kemmeter, 2002): monitoring, notification, simulation, controlling, measuring.

Based on the above aspects, (Knickle and Kemmeter, 2002) proposed the following tasks: definition of supply chain processes, identification of relevant logistical reference objects; definition of related events, and the design of status notifications with relevant information.

Moreover, from a technical view, the CMSB sys-

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tems promise to unlock additional value from supply chain processes beyond what has been realized from the implementation of Supply Chain Planning (SCP), Supply Chain Execution (SCE), Customer Relationship Management (CRM), and Enterprise Resource Planning (ERP) systems.

From a business perspective a CMSB solution aims to improve the management of supply chain processes and support the decision making, by providing the required information in order for supply chain partners to act proactive.

Table 1. Overview of existing literature on the system CMSB

Definition Author(s) … they are application systems that monitor, register, and Hunewald, 2005 evaluate disruptions, deviations within an enterprise and/ or among enterprises of a supply chain in real time to be able to take actions in real time … they can help the simulation, control, and measurement functions in supply chains … monitoring and notification are their two core functions … they decide by a set of rules how to react to occurred supply chain and logistics events … they gather logistics processes performance data … they allow the short-term planning, management and controlling of information regarding the operative logistic processes. It is a proactive concept that allows diverging high process complexity … they foster the inter-organizational visibility of critical objects throughout the supply chain … they introduce a control mechanism for managing events, in particular, exception events, and responding to them dynamically ... they ideally should be able to link the entire supply chain monitoring the flow of goods and information and alerting any time an event arises

Nissen, 2002 Meydanoglu, 2009 Straube, Vogeler and Bensel, 2007 Winkelmann, Beverungen, Janiesch, and Becker, 2008

Wieser and Lauterbach, 2001 Liu, Kumar and Aalst, 2007

Fantozzi, 2003

What is the meaning of the concept model of supply in case boimass (CMSB)

responding logistics and operations processes (Folinas et al., 2010), Table 2.

From the literature, a number of events’ categorization efforts can be identified. At first, (Nissen, 2002) categorised the events based on the exact time of their occurrence; an event is early or late if it occurs before or after the planned point of time. (Heusler et al., 2006) identified the events that occur as a result of an unplanned, unpredicted process (called unexpected or unplanned events) or not (expected or planned events).

(Bretzke and Klett, 2004) identified two categories based on the same criterion: those that require no corrective actions (regular events) and those that are unexpected (irregular events). For the examined supply chain, the categorisation can be based on the requirements of the cor-

Furthermore, in order to establish an effective and efficient framework for monitoring biomass supply chain activities (as well as field operation activities as far they are directly connected) the following characteristics / challenges need to be achieved:

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•

Information is gathered in real time from the native data sources (tags, sensors, etc.) without any attempts to duplicate data in a secondary repository

•

Associations, transformations, and metadata elements are implemented in real time to further describe and enrich existing data in the underlying data sources

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Table 2. The types of events that occur in the supply chain of biomass

Type Monitoring of urgent events

Monitoring of ordinary events Monitoring of the system’s performance Monitoring of the discrete events

Description Events that can cause an operational situation preset to be labelled an emergency (e.g., machine failure). The detected error/ alert information should be provided by barcodes, Radio Frequency Identification (RFID) or sensors and automatically being sent to an appropriate server, which can be accessed and analysed by the manager, service engineer or manufacturer Events that although they are expected, the exact time and place where they will take place are only known with uncertainty This monitoring type provides the data required for the estimation of the predetermined metrics that measure the system’s progress against the initial goals or latest planning.

This monitoring type provides the information of the start and termination of the continuous processes as well as of the discrete events occurring

•

Both structured and un-structured information are incorporated under a common framework with reference data being transferred from one format to the other

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Monitoring requirements are easily represented within the architecture according to semantics, without technical interpretation and the heavy need of information technologies to cope with the data sources

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Vital information is monitored and real-time events and intelligence are delivered directly in a totally visual manner to decision-makers that need to take action

•

Only exception conditions in the operations process are delivered to decision-makers, in order to be further analyzed and examined in detail.

off-line and online activities, since it refers to the operational planning and execution of field operations (mainly to the harvesting operation). The proposed architecture for the biomass supply chain is not divided into on-line and off-line activities since it regards the activities and events that take place concurrently with the physical “flow” of material, i.e. biomass.

RESULTS AND DISCUSSION The concept of supply and management of biomass A generic conceptual model is proposed for the management of events in a biomass supply chain. The focus is on the event management of inter-organisational logistics processes and the outline of the proposed model is depicted in Figure 2. The model constitutes a generalisation of the one presented by (Folinas et al., 2010) on the in-field logistics process management which was based on the business activities monitoring system paradigm. The devised framework for that proposed architecture was divided into Journal of Applied Engineering Science 9(2011)2, 199

Figure 2. Conceptual model of supply system biomes (CMSB)

The main structural elements of the conceptual model are presented and analysed in the following sections: Assessment: Initially, the related events of the examined supply chain need to be assessed and

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documented. Thus, this action involves the identification of the various types of events (urgent, ordinary, system’s performance and discrete events) that are presented in the previous section. Furthermore, this step includes the identification of the rules and the corresponding key factors. An important aspect of in supply chain management is that the various rules must comply with the constraints formed by the stochasticy of the “raw material” production system (agricultural operations management) in terms of availability and capacity of the labour and machinery resources, the biological attributes of the crop and soil, and the development of the weather. This layer consists of the identification of the thresholds and events that are important to monitor, note and / or will activate automatic behaviours.

Monitoring: This step includes the data acquisition process. First, it will be necessary to acquire detailed information about the actual machinery system that operates within the biomass supply chain (type, performance rate, reliability, operational state, etc.) and the crops to be harvested (yield maturity state, etc.). Secondly, at a particular point in time of the harvest season, the situation should be recognised with regard to development state of the crop, whether or not the schedule has been met so far, etc.

Identification: The role of this layer is to identify and capture the event that occurs and provide appropriate action to take according to predefined rules or settings. The next step will be the collection of the required contextual information to enhance these events.

Visualisation: Once the events have been identified and described, information needs to be delivered to the appropriate person or system for review and action. The visualization layer is simply a visual exception report and involves multi-delivery mechanisms such as alerts via email, dashboards, instant messaging, wireless devices, cellular phones, etc. The purpose of the visualization layer is not to overwhelm users with arrays of reports or analytical options but only to provide the information users need and when they need it. Thus, it must keep things simple by highlighting anomalies that users need to investigate and providing additional information only as needed. Once the events have been captured and visualized, the next step is to provide context to these events so that they can be ana-

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lyzed. For example, context may come from historical or real time sources, so, there is a need to understand and pass critical information without delay. Sometimes events need to be analyzed and business rules applied to derive key factors and alert content. In this stage, the proposed framework acts as an analytical tool that the user access by clicking on a metric or performance icon. It enables users to quickly see when performance is above or below expectations. Then, if desired, they can “click-on” a metric and get more information about what is causing the exceptional condition.

Response: The next step is the deployment of a specific and pre-defined action based on the contextual information that appeared in a visualised manner to the decision maker.

Feedback: Response outcomes are linked in a system monitoring effects of actions, unexpected events and any new information that can attribute to a validation, a refinement, or a reconsideration of the inter-organisational logistics processes, so that supplementary knowledge from observations, databases, sensors, etc., can be incorporated in order to revise plans. Finally, the above steps are deployed from the start since monitoring is a continuous operation.

CONCLUSIONS In this paper, a conceptual model for the management of inter-organizational events within the biomass supply chain was proposed. The proposed model is built on the Supply Chain Events Management technology. The goals of this model are: •

The identification and specification of events that occur during the execution of logistics and production processes in the biomass supply chain.

•

The provision of real time information in a visual manner (this is very critical in the examined business domain where users do not have a technical background) regarding critical data and performance measurements indexes.

•

The preparation of necessary notification based on information needs of the end users and managers. The main objectives were the provision of real-time information

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22) Reynolds, R. E. (2002). Transportation and infrastructure requirements for a renewable fuels standard. Technical report, No. 4500010570, Oak Ridge National Laboratory. http://www.ethanol-gec.org/information/ briefing/18.pdf.

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Paper sent to revision: 12.05.2011.

Paper ready for publication: 06.06.2011.

Journal of Applied Engineering Science 9(2011)2, 199

Paper number: 9(2011)2, 200, 339 - 348

BUSINESS STRATEGY OF PROVIDING CUSTOMER SATISFACTION AN EXPLORATORY STUDY IN QM CERTIFIED SERBIAN COMPANIES Dr Dragan Ćoćkalo * University of Novi Sad, Technical faculty “Mihajlo Pupin” in Zrenjanin Dr Dejan Đordjević University of Novi Sad, Technical faculty “Mihajlo Pupin” in Zrenjanin Savina Đurin University of Novi Sad, Technical faculty “Mihajlo Pupin” in Zrenjanin The key strategic objective of a company should be achieving and understanding the optimum level of customers’ satisfaction. This allegation is, conceptually, the objective of a wider analyses in this paper, as well as the model for providing customers’ satisfaction in the form of business strategy.

This theoretically-based model is harmonized with the following important concepts: quality management, business excellence and relationship marketing. The research (survey) which was carried out in companies and among the experts, on the territory of the Republic of Serbia, indicated justifiability of this model and its structure. The total of 600 organizations (all sizes; all QM certified) and about 100 experts (from the field of interest) were included in the research – the call for participation was accepted by 84 companies and 37 experts.

Keywords: Business strategy, Customer satisfaction, Quality management, Business excellence, Relationship marketing

INTRODUCTION

THEORETICAL BACKGROUND

Achieving business excellence and creating world class products and services, as a basic precondition for company’s growth and development in modern economy, are not functions of one organizational unit within the company, but the result of synchronized activities of all company’s functions, according to precisely defined objectives of the company. The objective of an organisation should be achieving and understanding the optimum level of customers’ satisfaction. This field represents a base of, at least, three concepts: quality management, total quality management and business excellence, as well as relationship marketing, which is conceptually, the subject of a wider analyses of this paper.

Customer satisfaction as a strategic objective Customer satisfaction (CS) can be defined in different ways. According to Kotler [1], satisfaction is “the level of a person’s felt state resulting from comparing a product’s perceived performance (or outcome) in relation to the person’s expectations.” Briefly, satisfaction level is a function of the difference between perceived performance and expectation.

In the contemporary global economy and highly competitive business environment, it might be fatal for a business organization to be non-customer oriented. In fact, only those customer-centered organizations that can deliver value to their customers will survive in the modern business arena. To “make” highly satisfied and loyal cus-

* Technical faculty “Mihajlo Pupin” in Zrenjanin, 23000 Zrenjanin, Đure Đakovica bb, Republic of Serbia; cole@tfzr.uns.ac.rs

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tomers, organizations throughout the world are striving to produce world class products and services of high quality. For a long time, CS was considered to be the key success factor for every profit-oriented organization as it affects companies’ market share and customer retention.

In addition, satisfied customers tend to be less influenced by competitors, less price sensitive, and stay loyal for a longer time [2].

collect customer demands and then compare the importance and performance (satisfaction) between the collected customers demands [10].

Concurrently, customer demands are not stagnant and cannot be manipulated by enterprises.

Therefore enterprises must periodically diagnose and filter these demands to set reasonable strategies to insure the survival of CS activities [11].

Many executives seem to trust their intuitive sense that high customer satisfaction will eventually translate into higher loyalty and with it ultimately into improved company performance /3/.

Thus achieving high customer satisfaction has become a central focus of corporate strategy for most enterprises [4]. However, “despite the claim that satisfaction ratings are linked to repurchase behavior, few attempts can be found that relate satisfaction ratings to actual repurchase behavior” [5]. That the validity of this assumption is all but given is nicely illustrated by Reichheld [6], who reports that while around 90% of industry customers report to be satisfied or even very satisfied, only between 30% and 40% actually do repurchase. Apparently, current knowledge doesn’t fully explain the prevalence of satisfied customers who defect and dissatisfied customers who do not [7, 8]. One of the reasons is that the relationship between satisfaction and retention is not a linear one, but moderated by several different variables. Oliva, Oliver, and MacMillan [9] stated that “the response function linking (…) satisfaction to customer response may not operate as is frequently assumed because the complexity of the relationship may be underestimated”.

Concepts related to customers’ satisfaction

Leading companies make customer focus a key element of the company’s overall strategy to differentiate themselves from competitors.

Satisfaction becomes a primary theme for top management in communications with a broad range of stakeholders. Focusing on satisfying high-value customers can be powerful part of the company fabric because it is meaningful to a broad set of stakeholders including employees, financial analysts, suppliers, and other allies.

Putting the customer first becomes part of the corporate positioning and differentiation in the market. The lack of management in CS strategies could be one of the many factors leading to an enterprise’s downfall. To effectively draft CS strategies, one must respect customer value and

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Quality components, such as solving complaints, cooperation of company’s representatives with customers, availability of products and services, cost and price policy and activities related to making contracts, have a great influence on customers’ satisfaction [12]. On the other hand, customers’ satisfaction influences the company’s characteristics, such as spreading positive information about the company and its services and products [13].

Many entrepreneurs do business by building and managing relationships without using the term of relationship marketing, which enables them to gain a better insight into customers’ needs and therefore act accordingly. The term “relationship marketing” (RM) itself was first introduced by Berry [14] in a services marketing context. Defined as marketing activities that attract, develop, maintain, and enhance customer relationships [14], RM has changed the focus of a marketing orientation from attracting short-term, discrete transactional customers to retaining long-lasting, intimate customer relationships.

Relationship marketing is a continual process which demands the following from companies: (1) continual communication with customers (provides correct definition of requirements) and (2) to integrate relationship marketing process into strategic planning (enables better resource management and anticipation of future customers’ needs). Brookes and Little [15] enhance the explanation of the effective marketing process by saying that this concept is based on data base management, interactive market communication and web marketing.

Business excellence presents a business strategy which demands from management complete commitment and acceptance of concept [16]. The EFQM model of business excellence is based on eight principles. The belonging criJournal of Applied Engineering Science 9(2011)2, 200

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teria are: leadership, policy and strategy, people – management of employees, partnership and resources, processes, customer results – customer satisfaction, people results – employees’ satisfaction, society results – the influence on society and key performance results [17]. All of them are the basis for self-evaluation whose purpose is to evaluate the “maturity phase” of the organization and to focus on the problems of further business improvement [18, 19, 20, 21, 22].

METHODOLOGY SETTINGS OF THE RESEARCH The companies coming from transitional countries, like those from the West Balkans (Serbia is among them), have problems with quality of their business and production productivity. Inherited inefficient production system, as well as transitional recession common for all countries in transition, influence these companies and may be blamed for their insufficient competitive capacity. The problem is especially obvious in the companies dominated by autochthonous private capital. The reason for relatively small number of Serbian companies that implemented quality system can be found in difficult financial situation of domestic economy and the implementation of QMS asks for considerable business efforts on the side of companies. What concerns most is the fact that almost all big companies have already implemented QMS. On the other hand, the majority of Serbian companies belong to small and medium size company sector (SME). Taking all the mentioned facts into account, it is not surprising that the concept of integrated management systems is mostly applied on Serbian market while the elements of business excellence serve more as theoretic-methodological base.

The concept of relationship marketing does exist, but only on the basic level and in small number of companies (mainly those in foregn ownership). There are, however, no clear indicators concerning this.

The presented model starts from, at least, two key pre-conditions: 1. The very incorporating of principles and criteria of business excellence in the given conditions, in other words – input and output elements of relationship marketing in defining policy, objectives and tasks in the organization (the sphere of planning quality in Journal of Applied Engineering Science 9(2011)2, 200

the future), showing strategic determination of certified Serbian companies to satisfy the requirements of customers and other stakeholders.

2. Wide involvement of organizational and management structure in the processes of expectations identification and monitoring, measuring and analyses would mean making stronger bonds between current activities and strategic decisions, where a satisfied customer is in focus.

Argumentation, even an indirect one, of these pre-conditions would be enough to show justifiability and acceptance of the model which, in the centre of the presented form puts satisfaction of customers and other stakeholders. In order to provide stable bonds between the rings it is necessary to incorporate wider organizational and management structures, especially in the processes directly oriented towards the customers.

Target groups in the research were: •

companies (production and/or services) which are certified according to the ISO 9000 standards and which work and/or have residence in Republic of Serbia; managers in quality and/or marketing sector in these companies, as the primary group,

•

experts, in the sphere of quality and/or marketing (with reference to the subject sphere, published works and/or cited), as a control group. They were to confirm the companies’ attitudes. It was interesting to see whether considerable differences would appear in the companies’ answers and the answers of those who were dealing with this matter from academic (university professors) or some other standpoint (e.g. consultants).

Surveying the available companies and experts was primarily realized over e-mail. The survey included about 600 companies and 100 experts.

The selection of companies was done primarily using Serbian Chamber of Commerce’s Database, while selecting the sample of experts was conveyed through the database of conatcts in JUSK – United Association of Serbia for Quality, as an independent and sufficiently representative body for Serbia. The total of 84 companies accepted the invitation to participate in the research (which is between 4,5 and 5,5% out of all certified companies in Serbia), as well as 37 ex-

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perts from the subject sphere. For the survey’s purpose a special questionnaire was created, taking care of methodology of the research; the communication principle was: one questionnaire – one company/expert. The survey was mainly realized in the first quarter of 2008.

This means that for p <= 0,05 there is a statistically significant difference in results. It was determined that significant statistic exception in the companies and experts’ answers (in general) didn’t exist, therefore, there was no discussion on this matter.

The structure of the surveyed companies was as follows: according to ownership structure the companies were mainly private (61 (72,6%)) and public (10 (11,9%)); according to the field of work: agriculture, hunting, forestry and water management 3 (3,4%), ore and stone mining 1 (1,1%), manufacturing industry 46 (52,3%), electrical, gas and water generation and supply 5 (5,7%), building construction 9 (10,2%) wholesale and retail trade; motor vehicles, motorcycles and house-ware/personal repair 8 (9,1%), traffic, warehousing and connection 3 (3,4%), administration and defence; compulsory social insurance 2 (2,3%), education 3 (3,4%), health and social care 3 (3,4%), other communal, social and individual services 5 (5,7%); according to the size: micro and small 14 (16,7%), medium 38 (45,2%) and big 32 (38,1%); position of the interviewed: mainly directors 10 (11,9%), leading managers 49 (58,3%), and consultants 3 (3,6%).

THE MODEL OF BUSINESS STRATEGY

The structure of the interviewed experts was: the majority of the interviewed were male (31 (83,8%)); the greatest number of the interviewed were over 50 years of age (13 (41,9%)) and between 30 and 40 (11 (35,5%)); level of education: the majority were PhD (15 (40,6%)), Master’s degree and Bachelors (10 (27%)); occupation (answered 22 (59,5%)): the majority (11) were university professors/college professors and 5 experts were employed as consultants; work position of the interviewed in their organizations (answered 36 (97,3%)): directors and/or owners and leading managers.

During the check phase of statistically relevant differences in the answers of different-size companies (types of companies: 1 – micro and small, 2 – medium and 3 – big, given in the following tables), the data types which appeared in the survey caused the application of two different methods of statistic analyses: Kruskal Wallis and One way ANOVA. ANOVA was used in comparison for both companies (total) and experts’ data as well. It was taken that the evaluation limit of results’ reliability, i.e. probability which enabled proclaiming that the data were error consequences or the random variations was p =0,05.

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In accordance with the previously said, modelling the acceptable concept that would satisfy customers’ requirements, integrate QMS, business excellence and relationship marketing seems possible and transitional solution. Therefore, the objective of the research was to create and present a qualitative theoretic model of a system for providing satisfaction of a company’s customers needs. This model assumes a process approach, appropriate marketing research in the beginning and corresponding evaluation in the end. The model is created to enable easier managing of these processes with the aim to achieve business excellence. Acceptance and justifiability of this mixture of concepts and the model should be proved in the future.

In the part of the research presented here, the framework of the business strategy for satisfying the customers’ requirements acceptable for Serbian companies is given, supported by statistic analyses of the answers provided by surveying the target groups. The attitude on justifiability and acceptance of the model will be created later on the ground of some quantitative indicators related to the mentioned qualitative theoretic model. The part of planning or incorporating the principles and criteria of business excellence and relationship marketing into the standard (ISO 9000) defined framework is the subject of a separate analysis. This serves to show justifiability and acceptance of strategically oriented form presented in the following picture.

Presentation of the model Figure 1 presents a model in a form of a cycle, in order to describe the model as a business strategy which puts the focused modules (subprocesses) in the environment of customers and other stakeholders, whose objective is the progress of the organization in whole. Such a business strategy is supported by business excellence and relationship. It can be the matter of dispute which “ring” of support is “older” and/or more important. The author of this paper thinks Journal of Applied Engineering Science 9(2011)2, 200

Dr Dragan Ä&#x2020;oÄ&#x2021;kalo and etc. - Business Strategy of Providing Customer Satisfaction An Exploratory Study in QM Certified Serbian Companies

that it is the matter of attitude, but their existence or the need for it has been shown in this research.

Analysis of research results concerning strategic components of the model Asked to evaluate the importance (using Likert 5-point scale) that should be paid to the principles of business excellence while defining policy, objectives and tasks in the organization, 66 (85,7%) (out of 77 (91,7%) of the interviewed in companies, or 33 (91,7%) (out of 36 (97,3%)) ex-

perts gave the answers which are shown, comparably, in the Table 1. All the principles were evaluated as significant or particularly significant (the lowest grade was given to corporative social responsibility by the experts - 3,39).

Having been asked to evaluate significance paid, or the one which should be paid, to criteria of business excellence at defining policy, objectives and tasks in the organization, the interviewed (63 (85,1%) out of 74 (88,1%)) in companies, and experts (33 (91,7%) out of 36 (97,3%)) evaluated the criteria and their application as significant (table 2).

Figure 1. The model for providing satisfaction of customerâ&#x20AC;&#x2122;s requirements as a business strategy Table 1. Comparative survey of average significance grade that should be paid to the principles of business excellence while defining policy, objectives and tasks in the organization

PRINCIPLES Average grade of the of business excellence interviewed in companies Results Orientation 4,17 Customer Focus 4,42 Leadership 3,82 Management by Processes and 3,80 Facts People Development and In3,76 volvement Continuous Learning, Innovation 3,68 and Improvement Partnership Development 3,94 Corporate Social Responsibility 3,58

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Average grade of the experts 4,39 4,61 4,18 4,06 3,88 3,79 3,94 3,39

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Таble 2. Comparative survey of average significance grade which should be paid to the criteria of business excellence at defining policy, objectives and tasks in the organization.

CRITERIA of business excellence Leadership Policy and Strategy People Partnership and Resources Processes Customer Results People Results Society Results Key Performance Results

Average grade of the interviewed in companies 3,73 3,87 3,68 3,65 3,90 4,47 3,58 3,52 4,23

Table 3, including the companies and experts’ grades, shows how important it is to take care about the criteria of business excellence by the leading management in management review. Affirmative answer was given by 65 (83.3%) out of 78 (92.9%) companies and 33 (91.7%) out of 36 (97.3%) experts. Here, statistically signifi-

Average grade of the experts 4,00 4,24 4,21 3,97 4,15 4,48 4,15 3,70 4,27

cant difference was noticed in the answers of the different-type companies (p = 0,043<0.05) and the grades are shown separately. High average grade of significance, paid to the criteria of business excellence, was noticed. In other words, they were evaluated as significant and particularly significant – the lowest grade was 3.50.

Таble 3. Comparative survey of the average significance grade paid, and which should be paid to the criteria of business excellence at management review

CRITERIA of business excellence Leadership Policy and Strategy People Partnership and Resources Processes Customer Results People Results Society Results Key Performance Results ANOVA significance test

Average grade of the interviewed in companies

1

2

3

3,67 4,08 4,33 4,17 4,17 4,67 3,92 3,92 4,67

3,54 4,04 3,69 3,69 3,73 4,42 3,81 3,46 4,35

3,73 3,88 3,50 3,62 4,04 4,23 3,50 3,62 4,12

Average grade of the experts 4,00 4,24 4,21 3,97 4,15 4,48 4,15 3,70 4,27

Group: companies

Between Groups Within Groups Total

344

Sum of Squares 0,727 2,434 3,161

df

2 24 26

Mean Square 0,363 0,101

F

Sig.

3,584

0,043

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It is interesting that a particular significance is paid to the principles and criteria which are directly oriented towards customers (the lowest average grade is 4.23); that shows readiness of the organizations to devote themselves to their customers, as well as the importance which the

experts give to this question.

Both companies and experts consider significant or satisfying input elements of relationship marketing concept, especially in the sphere of planning (Table 4).

Тable 4. Comparative survey of the average significance grade of input elements in relationship marketing concept

Input Elements of Relationship Average grade of the interviewed Average grade of the experts Marketing Concept in companies Understanding Customers Expectations

4,31

3,88

Building Service Partnerships

3,92

3,42

Empowering Employees

3,66

3,71

Total Quality Management

3,76

3,26

Comparative survey of the average grades which the interviewed used to evaluate the significance of output elements of relationship marketing, especially in the sphere of planning, is given in the

Table 5. It should be emphasized that all the elements were evaluated as significant, both by companies (81 (96,4%) answered the question) and by experts (35 (94,6%) of the interviewed).

Тable 5. Comparative survey of average significance grade of output elements in relationship marketing concept

Output Elements in Relationship Marketing Concept

Average grades of the interviewed in companies

Average grades of experts

Quality Product

4,64

4,06

Customer Satisfaction

4,44

4,26

Customer Loyalty

4,04

4,09

Increased Profitability

4,19

3,91

Considering the question which demands definition of management and responsibility over processes, identification of expectations, monitoring, measuring and analyses, a certain generalization can be noticed in the answers, given by experts, when they are compared to those obtained in companies. Nevertheless, we can find some similarities which are presented in the Table 6a for process identification of expectations and Table 6b for proces monitoring, measuring and analyses.

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It is interesting to notice the moving of responsibility (both companies and experts agree in this) from marketing top manager, for the process identification of expectations, towards sale top manager, for the process of monitoring, measuring and analyses. Especially expressed significance of organizational units (sectors) can be noticed: trade/sale, marketing, development sector and quality sector.

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Table 6a. Comparative review of management and responsibility over processes identification of expectations

Given answers

a) b) c) d) e) f) g) h)

Process identification of expectations Companies Experts 1 2 3 Top manager and/or owner 1 (5,6%) 15 (14%) 6 (9,2%) 13 (17,6%) Executive management 10 (9,3%) 3 (4,6%) Developement unit manager 1 (5,6%) 12 (11,2%) 4 (6,2%) 7 (9,5%) Marketing unit manager 3 (16,7%) 4 (3,7%) 15 (23,2%) 25 (33,8%) Trade/sale unit manager 5 (27,8%) 18 (16,8%) 14 (21,5%) 13 (17,6%) Quality unit manager (or QMS man- 3 (16,7%) 9 (8,4%) 9 (13,8%) 10 (13,5%) ager) Unit managers (generally) 3 (16,7%) 9 (8,4%) 6 (9,2%) Staff in direct contact with services 10 (9,3%) 6 (9,2%) 4 (5,4%) customers or those directly involved in services realization.

Kruskal Wallis Test Grouping Variable: companies Ranks frequency

companies 1 2 3 Total

N

Mean Rank 15,33 30,77 22,90

15 15 15 45

Test Statistics frequency 10,740 2 0,005

Chi-Square df Asymp. Sig.

Table 6b. Comparative review of management and responsibility over processes monitoring, measuring and analyses

Process monitoring, measuring and analyses Companies 12 (6,9%)

Experts

Given answers

10 (12,7%)

Top management and/or executive management

(a)

4 (2,3%)

7 (8,9%)

Developement unit manager

(b)

25 (14,3%)

24 (30,4%)

Marketing unit manager

(c)

41 (23,5%)

13 (16,5%)

Trade/sale unit manager

(d)

36 (20,6%)

21 (26,6%)

Quality unit manager (QMS manager) (e)

17 (9,7%)

2 (2,4%)

Employees in sale network

10 (5,7%)

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(f)

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DISCUSSION Certain problems concerning the acceptance of business excellence and relationship marketing in Serbian economy have the following consequences: the concept of integrated management systems are mainly applied on Serbian market with ISO 9000 series of standards as base.

However, it is obvious that strategic orientation towards satisfaction of customers and other stakeholders’ requirements is present in certified domestic companies. This is directly confirmed through accepting the incorporation of the principles and criteria of business excellence, concerning planning quality in the future. According to the research results, the criteria of business excellence should also be incorporated in the reconsidering phase by the management. Taking all into account, it is not surprising that considerable significance is paid to the principles and criteria which are directly oriented towards customers, with the lowest average grade of 4.23; this shows readiness of the organizations to devote themselves to their customers.

Wide incorporation of organizational and management structure in processes of measuring and analyses, according to the model, from top to employees in direct contact with customers, means making stronger bonds between current activities and strategic decisions where a satisfied customer and his expectations are in the focus. The analyzed results indirectly confirmed this aspect of the model, emphasizing the functions of top manager and/or owner, along with the other managers. Moving management and responsibility over processes can be noticed, going from marketing and top management towards sale top manager. As expected, special attention is paid to organizational units (sectors) like trade/sale, marketing, development sector and quality sector and their management.

It can be noticed from the results’ analyses and discussion that theoretic, strategic business model for providing satisfaction of customers’ requirements proved to be acceptable and justifiable for Serbian companies in relation to the context presented here.

CONCLUSIONS AND IMPLICATIONS The company’s objective should be achieving and understanding the optimum level of cusJournal of Applied Engineering Science 9(2011)2, 200

tomer satisfaction. The important step in achieving customer satisfaction is to make research of customers’ requirements in order to make good business decisions.

The model of business strategy for providing customer satisfaction, presented in this work, is harmonized with the requirements of ISO 9001:2000 series of standards, as well as with relevant proposals and criteria of business excellence, marketing requirements and specific characteristics and requirements of Republic of Serbia’s economy.The presented quality model can be considered acceptable and justifiable which has been supported indirectly by statistic indicators concerning planning and management, in other words, by incorporating the principles and criteria of business excellence and relationship marketing defined by the standard (ISO 9000).

The model itself has not been applied in practice or tested but, in our opinion, its use would contribute to a more complete and wider acceptance of the concept of business excellence and/or relationship marketing in the part of certified companies (standards ISO 9000 series) on the territory of the Republic of Serbia. In relation to some limits, we think that the model’s validity would be more complete if the research included a greater number of domestic companies, as a sample, even better if this research could cross the borders of Serbian territory and transfer to the countries of the West Balkans.

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10) Naumann, E., Jackson, D.W. Jr, Rosenbaum, M.S. (2001). How to implement a customer satisfaction program, Business Horizons, Vol. 44 (1), pp. 37-48.

11) Te-King, C., Chao-Ton, S. (2003). Using the QFD concept to resolve customer satisfaction strategy decisions, International Journal of Quality & Reliability Management,Vol. 20 (3), pp. 345-359.

12) Saraph, J., Benson, G., Schroeder, R. (1989). An instrument for measuring the critical factors of quality management, Decision Sciences, Vol,. 20, pp. 810-829.

13) /Evans, S., Burns, A. D. (2007). An investigation of customer delight during product evaluation: Implications for the development of desirable products, Proc. IMechE Vol. 221 Part B: J. Engineering Manufacture, pp.

1625-1640.

20) Rusjan, B. (2005, May). Usefulness of the EFQM Excellence Model: Theoretical Explanation of Some Conceptual and Methodological Issues, Total Quality Management Vol. 16, (3), pp. 363-380.

21) Teo, W. F., Dale, B. G. (2007). Self-assessment: methods, management and process, Proc Instn Mech Engrs, Vol 211 Part B, pp.

365-375.

22) Brkić-Spasojević, V., Klarin, M., & Curović, D. (2009). Dimenzije menadžmenta kvalitetom isporučioca u industrijskim preduzećima Srbije. Istraživanja i projektovanja za privredu, 7(23-24), pp. 67-71.

23) Petrović, P., & Milačić, V. (2010). Nacionalne tehnološke platforme Srbije - novi formalni okvir za reinženjering industrije Srbije.

Istraživanja i projektovanja za privredu, 8(3), pp. 147-161.

Paper sent to revision: 03.05.2011.

Paper ready for publication: 10.06.2011.

14) Berry, L.L. (1983). Relationship Marketing, Berry, L.L., Shostack, G.L., Upah, G.D., Emerging Perspectives of Services Marketing, Chicago, IL, American Marketing Association, pp. 25-8.

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EVENTS REVIEW

XXXVII International Conference - JUPITER 10. - 11. May 2011, Faculty of Мechanical Engineering, Belgrade During two days, 10 - 11.05. 2011, XXXVII JUPITER Conference (Jedinstveno Upravljanje Proizvodno - Informacionim Tehnološkim Resursima) was held at Faculty of Mechanical Engineering in Belgrade.

Total of 55 domestic and foreign papers were presented throught plenary sessions and five symposium s that includes the most important directions of development of contemporary and new technologies: 30. Symposium „CIM in the strategy of technological development”, 24. Symposium “CAD / CAM”, 33. Symposium “NU - Robots - FTS”, 39. Symposium “Management of production in the metal processing industry” and 17. Symposium “Quality Management”.

JUPITER Conference, as the most important activity of JUPITER Association (association of industry, universities, institutes, colleges and chambers) presented the most important results achieved during the last year.

The Conference was organised by Department of Production Engineering, with focus on three main goals: 1) to emphasize the importance of continuious education as a precondition to the development of Republic Serbia and industry and economy based on knowledge, 2) to initiate a new scientific and technological trends in the function of the domestic industry development, especially its reindustrialization, 3) to define the concept of a new scientists generation in the field of manufacturing engineering.

Round table discussion with title: Center for New Technology – decade 2010th – 2020th , has defined the role of Center as a scientific and technological base for new ideas, new concepts and products for industries. This implies the necessity of constant knowledge innovation through association with relevant scientific institutions and scientists from abroad, return of our scientists from abroad, organisation of national and international scientific conferences and international projects.

Between the two conferences at the Centre for New Technologies, modern computer classroom dedicated to students training in CAD software - Autodesk Inventor was formed. The idea is to make this classrom into commercial education center.

Prof. dr Ljubodrаg Tаnović Journal of Applied Engineering Science 9(2011)2

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ANNOUNCEMENT OF EVENTS IIPP QUALITY MANAGEMENT SCHOOL Considering business conditions of European market, quality has a significant role, not only in providing new markets, but also in maintaining the existing ones. Nowadays, customers do not only expect a quality product, but they require a proof that the company is capable to produce high quality products and provide quality services. Obtaining of this evidence should be the first goal for each company that has high aspirations when it comes to new markets but also standard’s procedure in order to maintain its reputation. Implementation is not complete if employees are not familiar with standards.

With the aim to closer inform the employees of the meaning and significance of ISO standards, Institute for research and design in commerce & industry – IIPP organize training “School of Quality”.

During the training participants will: • expend their knowledge about implementation of ISO standards, • learn how to maintain and improve quality level of companies • learne how to verify and improve business performance of companies Training will be held during four days in two locations. First lectures will be held at the Faculty of Mechanical Engineering in Belgrade, while the final lecture and the test will take place in attractive location in Serbia - Vrnjačka Banja.

Programme • Fundamentals of quality concepts, definitions, approaches • Standards, review and interpretation • Management Responsibility • System and process approach • Data management, information system • Statistical methods (engineering methods, quality management methods) • RISK, FMEA, FTA • Supply and storage, evaluation of supplier • Maintenance • Evaluation, audit, certification • Examples, practice, Deming management experiment • PAS 99 - Integrated Management Systems Result After implemented training, Qiipp consultant is able to assume responsibility for independent work in the following fields of activity: • Implementation of quality standards • Maintaining a high level of quality • Constant improvement of the quality system • Assessment and audits of own companies and their suppliers Candidates who passe the test will get a diploma “Qiipp consultant for implementation, maintenance, analysis, evaluation and testing, design and improvement of the quality system”.

Time and location: 19.11.2011. (first part) – Faculty of Mechanical Engineering, Belgrade 24-26.11.2011. (second part) -Hotel Aleksandar, Vrnjačka Banja Institute for research and design in commerce & industry Phone: 011/6300750; Fax: 011/6300751; E-mail: office@iipp.rs; web: www.iipp.rs

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ANNOUNCEMENT OF EVENTS

IIPP MAINTENANCE MANAGEMENT SCHOOL Maintenance Management School presents practical experience in combination with adopted theoretical knowledge, thus creating maintenance management experts capable to perform and coordinate the maintenance of complex technical systems. Use unique opportunity to expand knowledge in the field of technical systems maintenance.

During fourdays training focus will give to the following topics: • • • • • • •

Maintenance Objectives and Policies Maintenance Concepts Maintenance Terminology Laws and Regulations Condition Monitoring Fault Finding Techniques Spare Part Management

• • • • • •

Corporate/Company Environment Work Planning Team Working and Communications Information Technology Quality Assurance (Systems) Environment and Occupational Health and Safety

The school program merges best local knowledge and experience modernized and harmonized with the recommendations of European Federation of National Maintenance Societies.

Since Maintenance Management School connected and unified local tradition and experience in the maintenance process with the European norms and requirements, it’s result is thus twofold - to all who signed up gives a chance to gain national certificate ’’Expert for maintenance management” and to those who can and want more, Maintenance management school opens the possibility of obtaining the International certificate “European maintenance manager”.

Result: More than 240 national certificates and 16 internationally recognized certificates: European Maintenance Manager.

Time and location: 19.11.2011. (first part) – Faculty of Mechanical Engineering, Belgrade 24-26.11.2011. (second part) -Hotel Aleksandar, Vrnjačka Banja The 24th International Conference on Efficiency, Cost, Optimization, Simulation and Environmental Impact of Energy Systems July 4–7, 2011 - Novi Sad, Serbia Central theme: International and regional cooperation for sustainable development of energy systems: Needs, methodologies, technologies, accomplishments, plans, and potential. An important area of emphasis would be the rapidly developing region of South-Eastern Europe.

Every effort would be made to encourage scientific, business, and personal connections between the SouthEast European energy community and its overall international complement.

Energy resource fossil: Biomass within broad coverage of renewable energies.

“Clean Coal” within broad coverage of fossil and nuclear power generation.

Organised by:

Faculty of Mechanical Engineering, University of Niš Faculty of Technical Sciences, University of Novi Sad Faculty of Mechanical Engineering, University of Belgrade Faculty of Mechanical Engineering, University of Kragujevac

The 2011 conference motto: International Smart Energy Networks of Cooperation for Sustainable Development Journal of Applied Engineering Science 9(2011)2

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BOOK RECOMMENDATION Complex vehicle comfort

By Jovanka Lukić, Ph.D. associate professor

Contemporary vehicles have to satisfy very high comfort level. In the other hand, vehicle comfort is strongly correlated with vehicle and passenger safety. Comfort aspect is very important both in design and refinement phase of vehicle development.

Monograph Complex vehicle comfort is retrospective of author`s research results. Book consists of seven chapters.

Topics covered included: •

Vehicle packaging,

•

Ride comfort,

•

Acoustics comfort,

•

Thermal comfort,

•

Visual comforts and

•

Infotainment systems.

Author`s references are results of projects financed by Ministry of Science and Technology of Republic of Serbia.

This book is written for practicing engineers, designers, researchers and students.

Reviewers are: professor Miroslav Demić, Faculty of Mechanical Engineering Kragujevac, professor Ferenc Časnji, Faculty of Technical Sciences Novi Sad and Đorđe Diligenski, Senior Research Scientist, Vinča Institute of Nuclear Sciences.

Published by: Faculty of Mechanical Engineering Kragujevac Published: April 2011 Pages: 198 ISBN: 978-86-86663-71-9

The book is recommended by: Prof. dr Gradimir Danon

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INSTRUCTIONS FOR AUTHORS Send to: Institut za istraživanja i projektovanja u privredi Jurija Gagarina 12b, 11 070 Novi Beograd Phone: +381 11 6300750 Fax: +381 11 6300751 E-mail: nstanojevic@iipp.rs; astevanic@iipp.rs All manuscripts must be in English free of typing errors (please use Spell Checking).The maximum length of contributions is 10 pages.

Every manuscript submitted to IIPP will be considered only if the results contained in the paper were not already published, that are not currently in the process of publishing and not to be published in another journal. Each paper is sent to a review by two independent experts and the authors are obligated to adopt the observations and comments of the reviewers.

THE FORMAT OF THE MANUSCRIPT The manuscript should be written in the following format: • A Title, which adequately describes the content of the manuscript.

• An Abstract should not exceed 250 words. The Abstract should state the principal objectives and the scope of the investigation, as well as the methodology employed. It should summarize the results and state the principal conclusions.

• Not more than 10 significant key words should follow the abstract to aid indexing.

• An Introduction, which should provide a review of recent literature and sufficient background information to allow the results of the article to be understood and evaluated.

• A Theory or experimental methods used.

• An Experimental section, which should provide details of the experimental set-up and the methods used for obtaining the results.

• A Results section, which should clearly and concisely present the data using figures and tables where appropriate.

• A Discussion section, which should describe the relationships and generalizations shown by the results and discuss the significance of the results making comparisons with previously published work. (It may be appropriate to combine the Results and Discussion sections into a single section to improve the clarity).

• Conclusions, which should present one or more conclusions that have been drawn from the results and subsequent discussion and do not duplicate the Abstract.

• References, which must be cited consecutively in the text using brackets [1] and collected together in a reference list at the end of the manuscript and in alphabetic order.

Units - standard SI symbols and abbreviations should be used.

Abbreviations should be spelt out in full on first appearance, e.g., variable time geometry (VTG).

Meaning of symbols and units belonging to symbols should be explained in each case or quoted in a special table at the end of the manuscript before References Figures must be cited in a consecutive numerical order in the text and referred to in both the text and the caption as Fig. 1, Fig. 2, etc. Figures should be prepared without borders and on white grounding and should be sent separately in their original formats.

Pictures may be saved in resolution good enough for printing in any common format, e.g. BMP, GIF or JPG. Tables should carry separate titles and must be numbered in consecutive numerical order in the text and referred to in both the text and the caption as Table 1, Table 2, etc. The tables should each have a heading. Tables should not duplicate data found elsewhere in the manuscript.

Acknowledgement of collaboration or preparation assistance may be included before References.

Please note the source of funding for the research.

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INSTRUCTIONS FOR AUTHORS REFERENCES must be written in alphabetical order and in the following form: Journal: /Number/ (must match number in the text), Last name, Initial of the authors name, (Year of publication). Article title: secondary title. Title of the Journal (italic), volume number (number of the journal), page number. // Petrović, G., Petrović, N., Marinković, Z. (2008). Primena teorije Markova u mrežnim sistemima masovnog opsluživanja. FACTA UNIVERSITATIS Series Mechanical Engineering, 6 (1), 45 – 56.

Book: /Number/ (must match number in the text), Last name, Initial of the authors name, (Year of publication) Book title: secondary title, Place of publishing: Publisher. /2/ Vasić, B., Popović, V. (2007) Inženjerske metode menadžmenta, Beograd: Institut za istraživanja i projektovanja u privredi.

Book chapter: /Number/ (must match number in the text), Last name, Initial of the authors name, (Year of publication) Chapter title: secondary title, Book title: secondary title, Place of publishing: Publisher, page numbers. /3/ Vasić, B. (2004) Model Hardverskog resursa, Menadžment i inženjering u održavanju, Beograd: Institut za istraživanja i projektovanja u privredi, 95 – 97.

Internet source: /Number/ (must match number in the text), link to the page from which the text is taken, retrieved on (state the date) /4/ http://www.autogume.net/veleprodaje/kelena/, retrieved on November 7th, 2010 INDEXING Starting from 2006., only three years since the launch of the journal “Istraživanja i projektovanja za privredu“, all published articles are indexed in international ELSEVIER database through SCOPUS service. In this way, the work and results of the local scientiest are widely available as the SCOPUS is the largest database of abstracts and citations in terms of scientific publications and quality web sources which, above all, give the results of research in various fields.This database provides excellent information necessary for further work and scientists training with extensive search capabilities.

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SADRŽAJ

OD UREĐIVAČKOG ODBORA Dr Gradimir Danon

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REZIMEI RADOVA Dr Nenad Šekularac, Dr Jelena Ivanović Šekularac, Mr Jasna Čikić Tovarović OBLIKOVANJE NABORASTIH KONSTRUKCIJA PRIMENOM SAVREMENIH DRVENIH REŠETKASTIH NOSAČA

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Tatjana Mrđenović INTEGRALNI URBANI DIZAJN U REGENERACIJI – PRINCIPI ZA KREIRANJE ODRŽIVIH MESTA

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Darko Kosanović, Mr Suzana Filipović, Dr Nina Obradović, Dr Vladimir Pavlović, Momčilo Ristić EVOLUCIJA MIKROSTRUKTURE I KINETIKA SINTEROVANJA ZnO

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Mr Dragan Ružić, Dr Ferenc Časnji KARAKTERISTIKE TRAKTORSKIH KABINA OD ZNAČAJA ZA MIKROKLIMU

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Dr Dragiša Tolmač, Dr Slavica Prvulović, Mr Ljubiša Josimović, Dragana Dimitrijević KONCEPT MODELA I SISTEMA SNABDEVANJA I UPRAVLJANJA BIOMASOM

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Dr Dragan Ćoćkalo, Dr Dejan Đordjević, Savina Đurin POSLOVNA STRATEGIJA ZA OBEZBEĐIVANJE ZADOVOLJENJA KORISNIKA EKSPLORATORNO ISTRAŽIVANJE U SRPSKIM PREDUZEĆIMA SERTIFIKOVANIM PREMA QM STANDARDIMA

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OD UREĐIVAČKOG ODBORA Nakon devet godina rada u izdavačkom savetu časopisa, prvi put sam u prilici da pišem uvodnik za broj unapređenog časopisa sa novim naslovom koji sada izlazi isključivo na engleskom. Odlučili smo se za ove promene pažljivo mereći mane i prednosti ovakvog koraka. Bili smo svesni da će jezička barijera, odnosno nedovoljno poznavanje engleskog jezika, možda odbiti jedan broj domaćih autora i možda još više potencijalnih domaćih čitalaca.

Sa druge strane, Ministarstvo prosvete i nauke stimuliše istraživače da svoje rezultate objavljuju u časopisima sa što većim impact faktorom - što bi trebalo da pretstavlja istovremeno i svojevrsnu verifikaciju, odnosno međunarodnu potvrdu uspešnosti njihovog rada. Časopis koji izlazi na engleskom jeziku može da računa, osim na domaće i na autore iz regiona i iz Evrope. Na novom sajtu koji je u pripremi, potencijalnim čitaocima biće na raspolaganju objavljeni radovi koje će moći da “on line” pročitaju, što su istina i do sada mogli, ali ono što je novo jeste mogućnost da ih eventualno “skinu”, iskoriste ili komentarišu u svojim istraživanjima. Očekivano povećanje kruga čitalaca posredno će uticati i na povećanje uticaja našeg časopisa, odnosno na povećanu citiranost objavljenih radova i to pre svega u inostranstvu.

Unapređeni časopis ima još jednu važnu funkciju - stvaranje platforme za poređenje domaćih i stranih rezultata istraživanja i dostignuća iz oblasti inženjerskih nauka. To je trenutno prioritet jer imamo ambicije da ubrzano uđemo u EU i postanemo srednje razvijena zemlja sa bar 7.000 EUR po stanovniku.

Od toga bi trebalo bar polovina da se ostvari razmenom proizvoda i usluga sa inostranstvom. Za to Srbiji treba konkurentna privreda, odnosno širok asortiman proizvoda koje bi domaća privreda mogla da ponudi stranim kupcima. Pitanje je samo koji bi to proizvodi trebalo da budu, s obzirom da naš cilj ne bi trebalo da bude izvoz po svaku cenu - već onaj koji se danas obično naziva „održivim” i koji bi trebalo da obezbedi i dovoljnu akumulaciju za budući razvoj.

Sve potencijalne proizvode možemo podeliti u tri grupe: U prvu spadaju oni u čiju proizvodnju nikako ne treba ulaziti. To su masovni proizvodi kojima su pojedine fabrike prekrile svetsko ili regionalno tržište. U tu grupu, na primer, spadaju hemijske olovke ili upaljači za jednokratnu upotrebu. Kada čujete cenu i pogledate gde su proizvedeni, zapitate se kako se prodavcu isplati da ga prodaje, a proizvođaču da ga prozvede i dopremi do Beograda.

U drugu grupu proizvoda spadaju oni u čiju proizvodnju treba ući samo ukoliko se mora, na ograničeno vreme, dok se ne pripremite za nešto bolje i profitabilnije. Tu bih naveo dva primera. Prvi je FAS, odnosno Fiat automobili Srbija. Obnavljanje proizvodnje automobila u Srbiji svakako treba pozdraviti.

Ova fabrika i njeni kooperanti obezbediće posao za jedan deo Kragujevčana koji su ranije radili u Zastavi ili za njihovu decu. Drugi primer je veliki proizvođač i prodavac nameštaja Ikea. Mana ovakvih poslova je u tome što će u FAS-u raditi otprilike isto radnika koliko je u Zastavi nekada bilo inženjera.

Univerzitet u Kragujevcu je svojevremeno izrastao zbog potrebe za školovanjem stručnjaka za Zastavu i njene kooperante. Sada je situacija sasvim drugačija. Učešće domaćih stručnjaka u razvoju novog modela je bilo toliko malo da je i državna delegaciji, koja je bila u Torinu, više znala o novom modelu od Kragujevčana. Tako će verovatno biti i sa svakim narednim automobilom ako ceo projektat potraje, a nadamo se da hoće. Slično je i sa Ikeom. Tako veliki sistem ima centralni razvoj u jednom švedskom selu. Zapošljava uglavnom Šveđane i ponekog super talentovanog stranca. Sve one lepe stvari potiču odatle. Za dizajnerima u fabrikama u Srbiji nema potrebe. Zaključak je da ovakve poslove ne treba izbegavati, pogotovu u našoj situaciji, ali ne treba se na njih oslanjati ukoliko stvarno želimo u „bolju“ budućnost. Oni obezbeđuju egzistenciju, ali ne i napredak.

Treća grupa proizvoda je ona prava - kojoj treba stremiti. To su proizvodi koje sami osmislite, pripremite za proizvodnju i lansirate na tržište. Neko vreme ste jedini na tržištu i možete upravljati i cenom i uslovima prodaje. To svakodnevno viđamo, ali veoma retko se radi o proizvodima iz Srbije.

Za razvoj takvih proizvoda trebaju neki novi stručnjaci i dosta vremena, rada i para. Tim ljudima će trebati kvalitetna obuka na fakultetima kao i mogućnost da deo znanja steknu u inostranstvu. Potrebne su takođe nove fabrike i nove tehnologije i puno toga drugog. U tom lancu ima mesta i za projekte Ministarstva za prosvetu i nauku, ali i za naučne časopise, pa tako i za naš novi, a stari časopis Journal of Applied Engineering Science.

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REZIMEI RADOVA Broj rada: 9(2011)2, 195

OBLIKOVANJE NABORASTIH KONSTRUKCIJA PRIMENOM SAVREMENIH DRVENIH REŠETKASTIH NOSAČA Dr Nenad Šekularac - Univerzitet u Beogradu, Arhitektonski fakultet Dr Jelena Ivanović Šekularac - Univerzitet u Beogradu, Arhitektonski fakultet Mr Jasna Čikić Tovarović - Univerzitet u Beogradu, Arhitektonski fakultet Nаborаste konstrukcije predstаvljаju trodimenzionаlne konstrukcije odnosno prostorne strukture i kаo tаkve pripаdаju oblаsti konstruktivnih sistemа. Ovаj tip konstrukcijа se veomа dugo reаlizovаo u prаksi isključivo u аrmirаnom betonu izvođenjem nа licu mestа, što je uslovljаvаlo primenu veomа komplikovаne oplаte. Rаzvojem prefаbrikovаne grаdnje došlo je do unаpređenjа ovog tipа konstrukcijа tаko dа su nаborаste konstrukcije mogle biti izvedene montаžom prefаbrikovаnih elemenаtа i njihovom vezom, monolitizаcijom, nа licu mestа. Decenijаmа je ovаj tip konstrukcijа bio reаlizovаn isključivo u аrmirаnom betonu i tek u drugoj polovini XX vekа dolаzi do reаlizаcijа nаborаstih konstrukcijа primenom drugih mаterijаlа: čelikа, drvetа, stаklа, poliesterskih smolа i kombinаcijom više mаterijаlа.

U ovom rаdа izvršenа je аnаlizа postojećih nаborаstih konstrukcijа izvedenih u drvetu kаo i njihovа sistemаtizаcijа u pogledu primenjenog mаterijаlа, oblikа poprečnog presekа nаborаste konstrukcije, oblikа osnove i nаčinа izvođenjа. Anаlizirаni su svi fаktori koji utiču nа prijem i prenošenje opterećenjа kаo i stаtičku stаbilnost prostorne konstrukcije. Težište ovog rаdа predstаvljа istrаživаnje mogućnosti i nаčinа formirаnjа nаborаstih konstrukcijа primenom drvenih rešetkаstih nosаčа. Prikаzаn je i prototip cilindrične nаborаste konstrukcije reаlizovаne u ovom sistemu.

Oblаst primene drvenih rešetkаstih nosаčа kаo elemenаtа nаborаste konstrukcije predstаvljа oblаst kojа do sаdа nije dovoljno istrаženа u svetu i kod nаs i to u domenu teorije, kаo i prаkse. Ovаj rаd i njegovi konkretni rezultаti predstаvljаju proširenje sаznаnjа o oblаsti nаborаstih konstrukcijа mаterijаlizovаnih u drvetu i dаju doprinos sаvremenim inženjerskim konstrukcijаmа.

Ključne reči: drvo, drvene konstrukcije, drveni rešetkаsti nosаči, nаborаste konstrukcije, oblikovаnje nаborаstih konstrukcijа, cilindrične nаborаste konstrukcije, prorаčun trodimenzionаlnih konstrukcijа – prostornih strukturа Broj rada: 9(2011)2, 196

INTEGRALNI URBANI DIZAJN U REGENERACIJI – PRINCIPI ZA KREIRANJE ODRŽIVIH MESTA Tatjana Mrđenović - Univerzitet u Beogradu, Arhitektonski fakultet Regeneracija urbanih celina sa ambijentalnim vrednostima u kontekstu održivog razvoja preispituje ulogu urbanog dizajna. Savremeno shvatanje regeneracije se vezuje za kreiranje održivih mesta, koje karakteriše specifičan identitet, kroz zaštitu i promociju kulturnih vrednosti, socijalnu koheziju i ekonomski razvoj. Cilj rada je da razmotri ulogu urbanog dizajna kao transformativnog instrumenta u procesu regeneracije. U tom smilslu preispitaće se njegove mogućnosti u funkciji obezbeđivanja strateškog okvira za razvoj sa naglaskom na proces koji obezbeđuje kreativni milje za integraciju razvojnih sektora i pluralnih interesa. Obuhvat rada je definisan procesom urbanog dizajna u odnosu na racionalnu i kolaborativnu paradigmu u urbanom odlučivanju. Teorijski i konceptualni okvir će biti razmotren na primeru Plana za turističko aktiviranje Golubačke tvrđave. Glavni doprinos rada je opis integralnog modela procesa urbanog dizajna kao instumenta regeneracije. Očekivani rezultati istraživanja se odnose na opisivanje principa za kreiranje održivih mesta u regeneraciji.

Ključne reči: urbani dizajn, regeneracija, održivi razvoj, urbano odlučivanje Journal of Applied Engineering Science 9(2011)2

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REZIMEI RADOVA Broj rada: 9(2011)2, 197

EVOLUCIJA MIKROSTRUKTURE I KINETIKA SINTEROVANJA ZnO Darko Kosanović Institut tehnickih nauka-SANU Mr Suzana Filipović Institut tehnickih nauka-SANU Dr Nina Obradović Institut tehnickih nauka-SANU Dr Vladimir Pavlović Institut tehnickih nauka-SANU Momčilo Ristić Srpska Akademija Nauka i Umetnosti Cilj ovoga rada je proučavanje mikrostrukturne evolucije i analiza kinetike izotermskog sinterovanja ZnO. Prah ZnO je izotermski sinterovan (15, 30, 60, 90 i 120 min) u temperaturskom intervalu od 800 do 1200оC. Izračunate su vrednosti Lenelovog parametra i na osnovu njih analizirani procesi zgušnjavanja i transporta mase. Primenom skenirajuće elektronske mikroskopije izvršena je analiza evolucije mikrostrukture i utvrđena zavisnost srednje vrednosti veličine zrna ZnO od temperature i vremena. Rezultati ovih istraživanja omogućavaju razvoj novih fenomenoloških jednačina koje se mogu primeniti u analizi kinetike sinterovanog materijala na bazi ZnO. Ključne reči: ZnO, Sinterovanje, Kinetika.

Broj rada: 9(2011)2, 198

KARAKTERISTIKE TRAKTORSKIH KABINA OD ZNAČAJA ZA MIKROKLIMU Mr Dragan Ružić - Univerzitet u Novom Sadu, Tehnički fakultet Dr Ferenc Čašnji - Univerzitet u Novom Sadu, Tehnički fakultet Osnovni zadaci traktorske kabine su da obezbedi povoljno i udobno okruženje za rukovaoca i da ga zaštiti od vibracija i buke i drugih nepovoljnih uticaja. Težište ovog rada je na mikroklimatskim karakteristikama traktorskih kabina srednje kategorije. Pod mikroklimatskim karakteristikama kabine se misli na one konstruktivne faktore koji imaju uticaja na toplotne procese između kabine i njenog okruženja, uključujući i dejstvo na rukovaoca.

Jedan od načina za poboljšanje mikroklimatskih uslova i smanjenje energije potrebne za to je smanjenje toplotnog opterećenja kojem je izložena kabina. To se na prvom mestu postiže odgovarajućim merama izolacije od dotoka toplote iz okruženja kabine. Tu glavnu ulogu igraju karakteristike materijala i konstrukcija omotača kabine, koje su analizirane na postojećim rešenjima kabina traktora srednje snage, sa aspekta uticaja posmatranih konstruktivnih faktora na toplotne procese između kabine i okoline. Cilj rada je identifikacija najvažnijih uticaja, što bi trebalo da predstavlja podloge za projektovanje kabine za određeni traktor sa aspekta obezbeđivanja povoljnih mikroklimatskih uslova i smanjenja potrošnje energije na njeno ostvarivanje. Rezultati su pokazali da jedan od najuticajnijih činilaca predstavljaju zastakljene površine kabine, gde bi se izborom odgovarajućih osobina moglo postići značajno smanjenje toplotnog opterećenja kabine i direktno rukovaoca.

Ključne reči: traktor, kabina, ergonomija, mikroklima, stakla

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Journal of Applied Engineering Science 9(2011)2

REZIMEI RADOVA Broj rada: 9(2011)2, 199

KONCEPT MODELA I SISTEMA SNABDEVANJA I UPRAVLJANJA BIOMASOM Dr Dragiša Tolmač - Univerzitet u Novom Sadu, Tehnički fakultet “Mihajlo Pupin” Dr Slavica Prvulović - Univerzitet u Novom Sadu, Tehnički fakultet “Mihajlo Pupin” Mr Ljubiša Josimović - Tehnička škola, Požarevac Dragana Dimitrijević - Univerzitet u Novom Sadu, Tehnički fakultet “Mihajlo Pupin” Koncept modela i lanac snabdevanja biomasom, predstavlja sistem koji je veoma dinamičan. Razvijeni i poznati sistemi za upravljanje lancima snabdevanja tipično industrijskih proizvoda, direktno se ne odnose na slučaj biomase i lanaca snabdevanja. Ipak predložena metodologija u okviru ovog rada je u skladu sa industrijskim standardima. U okviru ovaga rada o biomasi - koncept modela i sistema snabdevanja i upravljanja biomasom (СMSB), data je podrška efikasnom upravljanju organizacionim događajima u okviru ispitivanih lanaca snabdevanja. Izvršena je analiza predloženog modela. Konceptualni model uključuje identifikaciju i specifikaciju događaja i pripremu neophodnih obaveštenja na osnovu potrebe za informacijama. Na osnovu toga u radu su dati sledeći relevantni elementi: pregled literature o sistemu CMSB, lanac i mreže snabdevanja biomasom, koncept sistema snabdevanja i upravljanja biomasom i vrste događaja koji se dešavaju u lancu snabdevanja biomasom.

Ključne reči: model, koncept, upravljanje, bioenergija, biomasa Broj rada: 9(2011)2, 200

POSLOVNA STRATEGIJA ZA OBEZBEĐIVANJE ZADOVOLJENJA KORISNIKA EKSPLORATORNO ISTRAŽIVANJE U SRPSKIM PREDUZEĆIMA SERTIFIKOVANIM PREMA QM STANDARDIMA Dr Dragan Ćoćkalo - Univerzitet u Novom Sadu, Tehnički fakultet “Mihajlo Pupin” Dr Dejan Đordjević - Univerzitet u Novom Sadu, Tehnički fakultet “Mihajlo Pupin” Savina Đurin - Univerzitet u Novom Sadu, Tehnički fakultet “Mihajlo Pupin” Ključni strateški cilj kompanije treba da bude postizanje i razumevanje optimalnog nivoa zadovoljenja korisnika. Ova tvrdnja je, konceptualno, cilj šire analize u ovom radu, kao i model za obezbeđivanje zadovoljenja korisnika u vidu poslovne strategije. Ovaj teorijski zasnovan model je usklađen sa sledećim važnim konceptima: upravljanje kvalitetom (QM), poslovna izvrsnost i marketing odnosa.

Istraživanje (anketa) koje je sprovedeno u preduzećima i među stručnjacima na teritoriji Republike Srbije, potvrđuje opravdanost ovog modela i njegovu strukturu. Ukupno 600 preduzeća (svih veličina, sva sertifikovana prema QM standardima) i oko 100 stručnjaka (iz predmetne oblasti) su bili uključeni u istraživanje - poziv za učešće je prihvatilo 84 preduzeća i 37 eksperata.

Ključne reči: poslovna strategija, zadovoljenje korisnika, menadžment kvalitetom, poslovna izvrsnost, marketing odnosa

Journal of Applied Engineering Science 9(2011)2

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