I
ESO
TECHNOLOGIES Alfredo Perucha and M.ª Dolores González
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Book cover design: Sergio Ramírez Book desing: RAG Illustrations: Alfredo Perucha, KUBIKARTE and Ana Hernández Junciel (Anph Boxed) Translation: Fernando Toda Iglesia and Daniel Peter Linder Molin
All Rights Reserved. No part of this publication may be reproduced or transmitted in any form or by any means, electronic or mechanical, including photocopy, recording or any other information storage and retrieval system, without prior permission in writing from the publisher.
© Alfredo Perucha Sanz and M.ª Dolores González Martínez, 2011 © Ediciones Akal, S. A., 2011 Sector Foresta, 1 28760 Tres Cantos Madrid - Spain Tel.: 918 061 996 Fax: 918 044 028 www.akaleducacion.com ISBN: 978-84-460-3399-8 Depósito legal: M-21.678-2011 Printed by Varoprinter Coslada (Madrid)
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INDEX 1 The Process of Solving Technical Problems..................
6
2 Expression and Communication Techniques...............
32
3 Stress-Resistant Structures............................................
54
4 Electricity........................................................................
72
5 Energy............................................................................
98
6 Machines and Mechanisms........................................... 126 7 Materials........................................................................ 148 8 Computers: Hardware and Software........................... 176 9 Communication Technologies. The Internet................ 204 Glossary.......................................................................... 222
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What
you’ll find in this book? Each unit in Technologies I follows the same basic outline:
Introduction Each unit begins with a double page which introduces the contents in a thought-provoking way. Each short introductory text will make you reflect on what you already know about the subject.
Presentation of the contents The contents are explained in texts written in fairly simple language, yet using the technical terms and language needed to write about them in English, of course. There are many illustrations to make the text easier to understand.
«Did you know?» Insertions Each «Did you know?» insertion will give you extra information and curious facts that can help you relate your new knowledge to your everyday life.
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References to the ATI program The ATI program is a sort of «virtual laboratory» which will help you to understand better the main contents of this book. You can find it at www.akaleducacion.com, where you have to select «Tecnologías» (Technologies) as the subject matter and then «Nivel ESO» (ESO Level) as your level. Apart from the ATI program, you will find many other amusing activities for practice at home.
Summary This section summarizes the main points and ideas that you need to remember from each unit.
Self-assessment In this final section you get the chance to assess for yourself how well you have understood the contents presented in the unit.
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1 The Process of Solving Technical Problems We live in a society that demands new and better levels of satisfaction, and we can reach those levels thanks to technology. All the objects that we use every day have been designed, analysed and built in order to cover the needs of humankind. In order to develop the things that we need, we use what is known as the projects method, which is a system that guides us so that we can analyse with precision the needs that we have to cover. Then we study the possible solutions, we choo足se the one that is best adapted to our needs, and we build a model. Finally, we eval足uate how the model works and correct any deficiencies that we have observed. In this unit, we will study the different stages (that is, the different steps or phases) in the projects method, and we will also learn how to write technical reports. We will also see how Information Technology (IT, the use of computers) offers us a set of tools that will make our work easier.
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1
he different stages in a technical T Project
Since the earliest times, humankind has always wanted to improve its living conditions. In order to do that, it has created new instruments or tools to make everyday life easier. We use technology to help us solve the inconveniences that we encounter. In ancient times, people built objects by intuition. They started with one element and then, over time, they modified it to make it better and more useful. Do you remember what prehistoric axes looked like? The basic principle on which axes work has not changed, but now the materials are more resistant and the tool is more effective.
Prehistoric axe.
Present-day axe.
Even though nowadays we still design objects intuitively, many of our every day utensils did not even exist until a short time ago. Bread toasters, for instance, were invented at the end of the 19th century. First the toaster had to be designed and then mass production began.
2
D esigning Products
Whether an object will be useful or not is one of the first considerations in the design process. There is no sense in manufacturing a product that serves no purpose. The fly-swatter in the illustration below could be call ed a «fly-friendly swatter», because it would be very hard to kill a fly with it, with that hole in the middle. This is what in technical terms is called the root cause: every design should serve the purpose it was designed for. The formal cause consists in analysing the reasons for creating a prod uct and examining the needs it will fulfil: we envision what it will look like, we draw it out on paper or on computer and we determine its size, and so on. But these preliminary ideas have to lead to something concrete, a prod uct with its own personality, shape, texture, colour, and so on. The ma terial cause is what we call the way a product’s design best makes use of the materials used in creating it. The last of these causes, the technical cause, is what we call the tech nical conditions that govern most designs. These conditions determine such aspects as aesthetics (colour, texture, and so on) and ergonomics (suitability of an object to the human body).
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The Process 3
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Planning the Design Process
As you can see, in the process of designing objects we have to follow cer tain guidelines, in the order mentioned. In the Technologies classroom, we are going to use a method known as the projects method, which will be very useful in carrying out our work. It is basically a process that is devel oped in a sequence, in a logical and coherent way. In this process we are given a number of suggested actions that will help us to analyze particular needs and to design products that can help us to satisfy those needs. Now, let’s see, step by step, the design process that we have to follow. Step 1: Identifying the problem and looking for solutions As an example, let’s imagine that the entrance to our school is on a street which has heavy traffic, and so it is dangerous for pupils entering and leav ing the building. Obviously this is a problem, and we have to try to solve it. If we ask a classroom group for ideas, we often get different solutions. Some people may suggest placing rumble strips on the street so that the sound will make drivers slow down; others may say that it would be better to place speed bumps so that cars have to go slower; still others may suggest a zebra crossing or perhaps a traffic light that the pupils can activate by pressing a button when they need to cross the street. Step 2: Choosing the best solution and planning the work After ideas are shared by all group members, we need to choose the solution that best solves our problem. In the example given, the best alternative appears to be the traffic lights, although it is the most expensive one and may cause more technical problems, or even have an excessively high level of difficulty. The distribution of tasks is the best way we have of carrying out our work correctly. Each person is assigned the activity that they can do best according to their abilities. Step 3: Building the model This is, undoubtedly, the step that we all like best. It is the moment when what we have planned starts to become a reality. To help you carry out your projects, in this book you will find information about materials, structures, mechanisms, electricity and so on. On the internet you will also be able to find useful ideas for building your project. Step 4: Evaluating our work This is a fundamental part of our project. We have to check to see if our model functions properly and complies with the specifications which we had set for ourselves. This is the time to make any necessary adjustments, modify things that are not working properly, etc. Step 5: Writing the technical project Once we have finished building our project, we have to prepare a tech nical report, known as the technical project. This document should contain the following sections:
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• Cover page: it must include the name of the project, the names of the members of the working group, the name of the school, and the date when it has to be turned in. • Table of contents: here is where you need to list the different sec tions of your technical project, giving the page where each one can be found. This includes the report, plans, outlines, etc. • Descriptive report: this is a detailed account of the steps that you have followed in building your model. It is a good idea to put some one in your working group in charge of writing down the things you do every day so that those notes can be used to write out the final version of the technical project. • Plans: this is a basic part of any technical report. As they say, «an image is worth a thousand words», and this is especially true when we need to get a mental image of what our model will look like. In this section you should include not only the plans of the most important parts, but also the diagrams for any electrical systems and for the differ ent mechanisms. In the coming units you will find information about the symbols that you will need to use when you draw these diagrams and the most important rules for an adequate presentation of your plans. • Process sheet: this is a detailed account of all the components that you have used, including the type of materials they are made of, their measurements and the function they carry out in the model. In the following illustration you can see an example of a process sheet. • Budget: in any technical project, economic considerations are very important. The last part of your report should include an account of the different products and materials that you have used, their cost per unit and the total cost once everything has been added up.
1
Year:
PROCESS SHEET
Group: N.
Date
Description
Material
N. of pieces
Fence Sketch
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The Process 4
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Building the Models
Once we have a clear idea of what we are going to build and how we are going to plan it, we can start working on our model. The first question that arises is the base on which we are going to place our model. Obviously, it will have to be made of material strong enough to support it, and also have the adequate measurements. Wood makes the best material for the base; you can use chipboard (about 10 mm thick) or plywood (about 4 mm thick). If you are going to build a small model you can use strong cardboard. When cutting the base for your model you should try not to waste mate足 rials, making your cuts starting from the edges of the original board.
2 2
Incorrect cuts.trazadas Piezas mal Piezas mal trazadas
Correct Piezas bien cuts. trazadas Piezas bien trazadas
If your project is about structures, you can recycle materials. For example, you can use lollipop or ice cream sticks. You can also build your own com足 ponents by rolling up sheets of used paper (scrap paper). Using simple components like these, if you place them well, you can build very resistant structures. In the following unit you can find resources for structures which may be useful in solving problems that you may find when building your models.
Chipboard and plywood boards of different sizes.
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5
Evaluating the Design Process
Once the project is finished, all members of the group have to check that it works as planned. Depending on the level of difficulty, it may be better to carry out this evaluation part by part. In the first place, the electrical circuit should be checked, making sure that the contacts have been prop足 erly made, that the power source has the right voltage, and so on. Since our traffic lights example is fairly difficult, the electrical diagram should be made first. If necessary, ask your teacher for advice. Now we can check the functioning of the electric programmer and the sequence of the traffic lights, solving any possible errors.
Having come to this point, some members can start building the two traffic lights while others prepare the structure on which to mount the complete model.
Now we can assemble the model, and then we need to check a number of things: does it work properly? Can anything be improved? Have we carried out the process in the way we had planned it? We have to analyse these questions.
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6 Information
Technology Resources for Writing Technical Reports
From what has been said above, it is easy to see that in order to prepare a technical report you need to write, draw, and make calculations. Information Technology (IT), the use of computers, offers us applications that can be of great help for all this.
6.1. Text Processing Software Text processing programs (also called word processors), which are probably familiar to you by now, allow us to edit our written work and present it in a clear and orderly way. Depending on the operating system in your computer, you will be able to use either Word, if it is running on Windows (part of the Office pack) or Writer, if it is running on Windows or Linux (part of the OpenOffice pack).
6
Microsoft
Office
7
Word
OpenOffice.org
Writer
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6.1.1. General Aspects of a Text Processor (also called a Word Processor) Any text processing program offers nearly endless possibilities for editing your writing. However, in this unit we will look only at the most impor tant features. When you are familiar with them, you will be able to pres ent your work in a neat and orderly way. The text processing programs presented here basically work in the same way, and the only differences are usually in the location of the different tools and the way in which they are presented on the start screen. If your computer runs on Windows and includes the Office 2007 pack, then the text processor included is Word 2007, and the start screen is the one you can see in the following illustration. Fichas Tabs
26
Grupos de herramientas Groups of tools
The most relevant elements on the start screen are: BotonMicrosoft de Microsoft OfficeOffice button
Herramientas de Quick access tools acceso rapido
27
• On the upper left hand side, the Microsoft Office Button. When you click on it, the most common options for documents are displayed: open a document, save it, print it, and so on.
Redo Undo Save
• Next to the Microsoft Office Button are the quick access tools, Save, Undo, Redo (Guardar, Deshacer, Rehacer). You can include new tools by clicking on the black arrow to the right of Redo (Rehacer).
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As you can see, the commands for different tools are shown in command tabs: Home, Insert (Inicio, Insertar) etc. Within each of these tabs they are grouped in a homogenous way, for example Clipboard, Font (Porta足 papeles, Fuente) etc. We will now describe briefly the most important commands included under the Home tab (Inicio). Clipboard group:
Home
29
Cut Copy
Paste
Font Group: Font type
30
Clipboard
Paste
Paragraph group
Font size
Bullets and Numbering
Indent buttons
Sort Selected Lines
31
Bold Italics Underline
Highlight Font colour Superscript
Subscript
Align text
Line spacing
Shadow
Table borders
When you have finished your work session, you have to save your doc足 ument. In Word 2007 you click on the Microsoft Office Button and a window opens, showing you the most important options. Click on Save as (Guardar como) and a new window will open showing you the places where you can save information (hard drive, pen drive, etc.). Choose one, give your document a name and press Enter (Intro) to save it.
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When you wish to exit the program, click on the Microsoft Office Button and then on Close (Cerrar). If the word processor on your computer is Writer, which is part of the OpenOffice.org pack (there are versions for Windows and for Linux), then you will see this:
34
Untitled 1 - OpenOffice.org Writer File Edit View Insert Format Table Tools Widows Help ABC PDF
Arial
ABC
?
NC S
18
ab
On the upper part of the Start window you will find the Menu bar (Barra de menús desplegables). The most important commands can be seen in the following illustration.
35
File Edit View Insert Format Table Tools Widows Help
Inside each of the menus you can find other options. The most important ones are shown in the following figures. Many of the commands can also be accessed more easily from the Tool Bar.
36
38
File Edit View Insert Format Table
File Edit View Insert Format Table New
37
Open... Close Save
t View Insert Format Table Tools Wido
Undo: Change style
Character...
Can´t Restores
Parrgraph...
Cut
Bulles and Numbering...
Copy
Alignment
Paste
Save as...
Find & Replace...
Print... Exit
Just below the Menu Bar you will see the Tool Bar, and on it you will find the buttons for the most frequent commands used in editing texts. Open
Save
AutoCorrect ABC
39
Undo
Redo
ABC
Cut
?
Copy
Paste
Below the Tool Bar you will find the Formatting toolbar (Barra de for mato). On it you will find all the options the program offers for editing letter types and sizes, paragraphs, etc.
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Font type Arial
Font size 18
Align text
Font colour
NC S
Bold Italics Underline
Background colour ab
Bullets and Indent Numbering
Highlight
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Now we are going to look at two operations which will be especially important when preparing your projects: How to insert drawings, photo graphs, etc. and how to write formulas. 6.1.2. Inserting Illustrations in your Texts One of the most frequent actions you will need to carry out when prepar ing your reports is inserting drawings or photographs. To insert an image (called a picture in the program) when using Writer, you must do the following:
1.º On the Menu Bar, click on Insert (Insertar) using the left button on your mouse, and you will see all the options for this menu. 2.º Then choose the Picture option (Imagen). When you place the mouse cursor (also called pointer) on top of it, other options will open. Click on From file (A partir de archivo). 3.º A new window will open, showing you all the storage devices available on your computer. Go to the one where you have your picture file, click to open it, and the image will appear in the centre of the page that you are working on. Notice that on the edges of the picture, in the corners and in the middle, small green squares appear. These are «extenders» (called sizing handles). To adapt the dimensions of your image to the size that you want, click on one of the squares in the corners using the mouse cursor and resize the image. In this way you will maintain the proportions of the original image when you change the size. 4.º If you want to have your image surrounded («wrapped») by text, first select it, and then click on the corresponding button on the Frame toolbar (Barra de propiedades) which opens when you have inserted an image and choose Page Wrap (Ajuste de página).
8
Graphics
Wrap Off Page Wrap
Wrap Through
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If your computer is running on Windows, and you are using Word 2007, click on Insert and then click on Picture (Imagen).
Just as in the case of Writer, a new dialogue window opens showing the storage devices on your computer. Select the one that has your picture file and when you click on it the image will appear on the page of your document where you have your cursor. Notice that now a small circle appears in the centre at the top of the image; you can use this to rotate the image.
Now if you look at the upper part of the screen you will see a toolbar with different styles, from which you can choose borders, shadows, etc.
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If you want to have your image surrounded (“wrapped”) by text, with your cursor on any part of the image, click on the right button. A menu is displayed. There, you choose Arrange (Ajuste de texto) and then Text Wrapping (Cuadrado). 6.1.3. Editing Formulas in Your Text Both Word and Writer have very powerful formula editors. You can use them to compose all sorts of formulas that you may need. In Word 2007, on the Insert menu, you have two options. When you click on Insert, on the right side of the toolbar you will see the command for Equa tion (Ecuación). When you click on it, a dialogue window will open, offering you several possibilities.
The other option in Word 2007 is to click on the Insert menu and then go to the Object option (again on the right side of the toolbar). When the window opens, choose Microsoft Equation Editor 3.0. The new window that will open has all the editing options (Greek letters, symbols, etc.) and you write your formula in the lower part.
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With Writer you can proceed in the same way. From the menu bar, in Insert, select Object. When the new window opens, click on Formula. What the program does then is to open an application called OpenOf足 fice.org Math.
Something else that you may need to do in preparing your technical reports is to include tables for things like budgets or process sheets. The system is very similar in Word and Writer. In both cases you need to click on Table in the menu bar.
If in your tables you need to include numerical data with mathemati足 cal operations involving different data in the table, you will probably be better off using another application, a spreadsheet, which is used for making calculations. Spreadsheets are described here briefly, and then in more detail in the following unit.
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6.2. Spreadsheet Programs As you probably know, most computer operating sys足 tems include a calculator, which is often very useful. However, when we need to operate with a large number of figures and do many calculations, it is better to use a spreadsheet. Spreadsheets are computer applications that allow us to enter figures into a table and to establish mathematical relationships among them. Just as in the case of word processors, the application you use will depend on the operating system in your computer. You will be using Ex足 cel (which is part of the Office pack) if it runs on Win足 dows, and Calc (part of the OpenOffice pack) if it runs on Linux (but also on Windows).
Linux Calculator. Windows Calculator.
9
Microsoft
Office
Excel
10 OpenOffice.org
Calc
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B3
11
A
The basic element in these programs is the cell. Cells are the squares where you insert your data. To name a cell we use a system like the one used when you play «Sink the Fleet» (also called «Battleships»): first you name the column (vertical cells) and then the row (horizontal cells). The following illustration shows how cell B3 is named.
HIT B
C
D
E
F
1 2
Inside each cell you can introduce numerical data, text, graphs, etc. Here we will only be looking at the introduction of figures (numbers).
3 4
6.2.1. Selecting Cells, Columns and Rows
5
In order to select a cell, move the mouse pointer over the cells and leftclick on the one you want. The border around the cell then becomes A thicker and you can see a small black square in the bottom right-hand corner of that border. You will also see that the cells showing the row (numbers) and column (letters) have changed colour. A
12
B
C
D
E
1 2 3
If you want to select a complete row or column, all you have to do is click on the cell showing the number or letter for that particular row or column. A
13
B
D
E
1
A
14
2
3
3
1 2 3
B
C
D
B
C
D
E
1
2
A
15
C
E
Finally, if you want to select a group of cells, all you need to do is click on the one where you want to begin and move your mouse cursor, keeping the left button pressed, until you have selected all the cells you need. Such a group of cells is known as a rank.
Rank
6.2.2. A Practical Case As an example, let’s create a table with some materials that you may need to use in the Technologies classroom and their prices. • 2 chipboard planks at 2.5 € each • 3 plywood boards at 1.25 € each • 2 bars of thermoplastic glue at 0.35 € each • 1 motor at 2.35 €. • 2 small pulleys at 0.45 € each • 2 large pulleys at 1.20 € each
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NOTE: in English you use points (dots), not commas, for decimals. But if you use a spread sheet in Spanish, you will need to use commas. In the first row we write the names of the data that we want to introduce: amount, descrip tion, price per unit and total price. First, click on cell A1 and write «amount». Then move to cell B1, click on it, and write «description». Carry on like this until you have entered all the data you need in the first row. (In this case, C is «price per unit» and D is «total price»). A
16
1
B
Amount
C
D
Description Price/unit
E
Price/tot
2 3
The next step is to complete the table by introducing all the data. Fill in the cells under each of the columns (A, B and C in this case). Notice that in column B, if you wrote, for example, «description of the item», then the text is longer than the cell, and you will only see the first part of it. A
B
1 Amount
17
C
D
Description Price/u
E
Price/tot
2
2
chipboard pl
2,5
3
3
plywood boar
1,25
4
2
bars or thermo
0,35
5
1
motor
2,35
6
2
small pulley
0,45
7
2
large pulley
1,2
8 9 10
In order to adjust the cell to the length of your text, set the mouse pointer on the line separating cell B (which is where you have the problem) from cell C. Notice that18 the pointer mark changes, and will now look like the one in the illustration on the left.
A
B
C
When you double-click with the left button on the dividing line, the width of the column adjusts to the length of your text. A 1 Amount
19
B Description
C
D
Price/u
2
2 chipboard planks
2,5
3
3 plywood boards
1,25
4
2 bars of thermolastic glue
0,35
5
1 motor
2,35
6
2 small pulleys
0,45
7
2 large pulleys
1,2
E
Price/tot
8 9 10
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6.2.3. How to Introduce Formulas In column D you are going to get the result of multiplying the number of units of each of the materials by the price per unit. To do that, you need to introduce the formulas available in the spreadsheets. All the mathematical operations that you need to carry out on the spreadsheet are introduced in the formula bar (Barra de fórmulas) located just above the letters for the different columns. VERY IMPORTANT: before you type a formula, you have to type the “equals” sign (=), otherwise the spread sheet will not recognize it as a formula.
20
= 0
Sign =
Formula bar
Our results will be shown in column D, and in or der to carry out the operation you need to place the mouse pointer on cell D2 and click on it. Now type the equals sign ( = ) and you will see that it also appears in the formula bar.
Formula bar
Did you know? Basic mathematical operations21 are carried out with the following keys:
Subtract Add + (Sum)
*
Multiply
The first operation we need to carry out is to multiply the number of chipboard planks (2) in cell A2 by the price per unit (2.5) on cell C2. It’s very easy: click on cell A2, press the asterisk (*) key, and then click on cell C2. You will see that the formula (=A2*C2) appears in cell D2 and also on the formula bar. For the spreadsheet to accept the formula you have to take the cursor to the button on the formula bar and click on it. Then the result (5, in this case) will appear in D2.
Divide
In order to extend this formula (multiplication) to all the other materials and their prices, click on the cell which contains the formula which you wish to extend (in this case cell D2). Set the cursor on the little square in the bottom right-hand corner of the cell. The large white cross on the cursor becomes the smaller black cross. Press the left button on the mouse and drag the cursor along the line of the cells to which you want to apply the formula. You will now get all the results. The finished table should look like this: A
22
1 Amount
B Description
C
D
Price/u
E
Price/tot
2
2 chipboard planks
2,5
5
3
3 plywood boards
1,25
3,75
4
2 bars of thermoplastic glue
0,35
7,7
5
1 motor
2,35
2,35
6
2 small pulleys
0,45
0,9
7
2 large pulleys
1,2
2,4
8 9 10
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If you want to obtain the result of adding all the materials, you can use the Au toSum command (S, Autosuma) on the upper right hand part of your screen. To use this command, all you need to do is select the rank in which all the total prices are listed (in this case cells D2, D3, etc.). Then you click on S. You will see that the total sum appears in the cell just below the last figure listed in column D (in this case, D8). A 1 Amount
23
B Description
C
D
Price/u
E
Price/tot
2
2 chipboard planks
2,5
5
3
3 plywood boards
1,25
3,75
4
2 bars of thermoplastic glue
0,35
7,7
5
1 motor
2,35
2,35
6
2 small pulleys
0,45
0,9
7
2 large pulleys
1,2
2,4 14,1
8 9 10
Result of the addition (Sum)
6.3. Drawing Programs Something else that you will need to do when you are preparing technical reports is to include drawings. As you may know, there are basically two types of computer applications for drawing: bitmap editors and vector graph ics editors. Bitmap editors draw objects using small points, known as pixels, and they take up a lot of space in your computer when you save them. In Windows, you can find the application called Paint, under Accessories in the pro gram menu. This is a bitmap editor.
Vector graphics editors have many advantages over bitmap editors. Some of them are: • They take up very little space in the computer. • Drawings can be modified easily, and they can be enlarged when you print them without losing definition. • They offer a very wide range of colours and textures to fill in your drawings. • You can make complex drawings by combining several simpler shapes. • As you carry out different parts of a drawing, the new parts are situated in the upper layers, though they are unaltered. Later you can modify the order of the different «layers» of your drawing until you obtain the result you want.
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Two well-known computer-assisted drawing programs that use vector graph足 ics editors are:
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1) OpenOffice.Draw, which can be run on Windows or Linux and is included in the OpenOffice.org suite. This is free software.
Start screen for Draw.
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2) CorelDRAW. This program is much more powerful than Draw, but it is not free (it is licensed software).
Start screen for CorelDRAW.
OpenOffice.Draw will be explained in more detail in the following units.
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The Process 7
of
Solving Technical Problems
Safety in the School Workshop
In Technologies we will be using a number of machines, materials and elements that will help us to learn easily. Apart from the normal class room, we will be working in the school workshop and in the compu ter room. In each of these places a number of rules must be followed so that we can work safely and efficiently. It is very important to follow the safety regulations in the school work shop. In the following illustrations you can see some examples of how you must act when using certain tools.
The tip of the soldering iron is very hot: – Be careful not to burn your clothes. – The power cord should be in good condition. – Be careful with fellow pupils near you. – Do not inhale smoke arising from the soldering iron. – Do not put the welding wire in your mouth; it contains lead.
Do not use your hand to hold objects that you need to saw: use the clamp. Materials that have been cut or sawed may have sharp ends: use protective gloves.
When using a cutter or any other cutting object, always make the cut away from your body.
Thermoplastic glue guns have very hot tips. If you burn yourself, tell your teacher and put ointment on the burn.
If you are using the drill: – Do not forget to remove the key that tightens the drill bit. – Make sure that you know where the STOP switch is located.
Did you know? In the Technologies school workshop there must be a first-aid kit with the basic elements needed in case of minor accidents. The basic equipment should consist of: • Tweezers and scissors • Alcohol and hydrogen peroxide • Betadine (iodine solution) • Sticking plaster (band-aids), cotton and sterile bandages • Ointment for minor burns
First-aid kit.
Do not handle cutting tools in a way that you may lose your hold on them and injure yourself.
When painting a model, if you are using enamel paint, protect your clothing and make sure you have good ventilation.
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Summary When designing a product, the first thing that has to be considered is its utility. In technical language this is known as the root cause. The ideas and reasons for creating a product, examining the needs it will fulfil, and envisioning what it will look like are known as the formal cause. The way in which a product’s design best makes use of the qualities of the materials used in creating it is known as the material cause. The technical conditions governing the manufacture of designs are known as the technical cause. These conditions include such aspects as aesthetics (colour, texture, and so on) and ergonomics (suitability of an object to the human body). In planning our designs, we need to follow these steps, in this order: • 1.st Identify the problem or need and look for solutions. • 2.nd Choose the best solution and plan our work. • 3.rd Build the model. • 4.th Evaluate the product of our work. • 5.th Write the technical project. Once we have completed our preliminary study, we have to build a model that complies with the specifications given, and then evaluate it. We need to check that it works properly and, if we find any faults, we must correct them. Information Technology (IT) offers us a range of applications that help us to prepare our reports in a clear and accurate way. • Word processors: -W ord for Windows (in the Office pack) or Writer for Linux or Windows (in the OpenOffice pack) • Spreadsheets (for calculations): - E xcel for Windows (in the Office pack) or Calc for Linux or Windows (in the OpenOffice pack) • Drawing software: -O penOffice.Draw for Linux or Windows (in the OpenOffice pack). This is free software. -C orelDRAW: much more powerful than Draw, but it is licensed software (not free).
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Microsoft
Office
Word
OpenOffice.org
Writer
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The Process
SELF-ASSESSMENT
1
of
Solving Technical Problems
I n technical language, when we speak about the root cause, we are referring to:
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a) The idea that the product designed should be sold in as many commercial outlets as possible. b) The idea that the product designed must be ergonomic and safe. c) The idea that the product designed must satisfy the needs for which it was designed.
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The term ergonomics refers to: a) The logic that must be followed in de signing products. b) The suitability of manufactured products to the human body. c) The distribution and sale of products to satisfy market needs.
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hen we talk about the aesthetic aspects W in the design of an object, we mean that: a) Its measurements must be adequate so that it can be used comfortably. b) The manufacturing process must be adequate in order to bring a competitive product to the market. c) The colour, texture, finish, etc. are pleas ing to the eye and satisfying to use.
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The projects method is the name given to: a) An ordered sequence of steps that must be followed in the building of a model. b) A series of logically ordered steps that help us to identify and solve problems. c) A way of working in the school work shop, guided by safety regulations that we must follow in order to avoid accidents.
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I n order to build a resistant base for a mod el, the most adequate material would be: a) Plywood b) Chipboard c) Corrugated cardboard
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T he most important sections that should appear on a process sheet are:
mong the Information Technology re A sources that we can use to prepare our tech nical reports, the most frequent ones are: a) Word processors, spreadsheets and dig ital applications. b) Drawing software, word processors and process sheets. c) Word processors, spreadsheets and drawing software.
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T he main difference between the word processors called Word and Writer is: a) Word is free software. b) Writer is free software. c) There is no difference; they are almost the same.
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In order to identify a cell on a spreadsheet, you should name: a) First the row and then the column. b) It makes no difference. c) First the column and then the row.
10 In order to introduce a formula in a spread sheet, first of all you need to write this sign: a) + b) / c) =
11 In order to add the figures in a selected group of cells (a rank) you should use the following formula: a) =SUM(A1_C3) b) =SUM(A1-C3) c) =SUM(A1:C3)
12 On the formula bar of a spreadsheet, you see the following: =PRODUCT(A1/A2). The result that you will obtain in the cell where you have your cursor is: a) The multiplication of the value of cell A1 by that of cell A2. b) The division of the value of cell A1 by that of cell A2. c) This formula cannot be carried out.
a) The description of the model, the ma terials employed, and a plan or outline. b) The order number, a description of the model and the materials. c) A description of the model, the mate rials and the date.
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