Hello, everyone, this is our first class in Engineering Graphics, and today's topic is "Language for Engineers". What is the Language for Engineers? Let us think about this. Actually, among the engineers, we have a way of communicating with each other across different fields, and that language used for communication is Engineering Graphics. In the years I teach Engineering Graphics, I realise that, it is less of a course for learning a technique, just drawing, how to draw a straight line straight or how to draw with precision. it is actually more of a course for learning a language, how to communicate with engineers, how an engineer can express the ideas in his mind effectively to his fellow engineers, and they complete a project together. From one engineer, completing his work, and passing it onto the next engineer and eventually, they accomplish magnificent work. So, I really enjoy teaching this course, because I don't feel like I am teaching a technique, I feel like I am teaching a course about communication and language. Let us look at this, we see a city. You can imagine how this city was constructed? When you see this city, you can imagine that a century ago, it might be vast grassland next to the mountains, and it has a river, it has a very different, natural scenery. But human may have lived here since hundreds of years ago, and gradually, they developed a city with such scale. This is the campus of National Taiwan University, so, you can see this city is Taipei. From what you can see, there are a great number of high-rise buildings; there is the school campus, the buildings, and in places that you cannot see, there are pipelines under the roads, there are over-passes above the roads, there is also the Mass Rapid Transit etc. There are many different types of engineering work in here. You can imagine, all these engineers in the city, from the past generations, many generations, the accumulation of all their work up to today, it became a city that is fit for human to habitat. This is the wisdom of uncountable engineers. How do they communicate their ideas among themselves? You can imagine that, for an engineer to express his imagination, his wisdom, his expertise, he must have an excellent tool, Engineering Graphics. In different fields of engineering work, there must be a tool that allows communication: Engineering Graphics. The engineers of the past must be able to communicate with the engineers of the present. There may be a city plan from a century ago, and now, we are to construct a building, how is it related to that hundred-year-old city plan? That also requires the basis of Engineering Graphics. So, we can imagine, in the current engineering environment, in the fine world that we live in, the basis of Engineering Graphics allows the communication between engineers, and so we are able to build such a world. There are two main focuses today: One, to understand the responsibilities of an engineer and the workflow of solving problems. Two, how to solve problems with Engineering Graphics, when should engineers use Engineering Graphic tools to solve problems, and which tool should he choose to use. So, what are the responsibilities of an engineer? Today, I can give you a brief introduction. There are many different types of engineers, but mostly, their responsibilities are as follows: Let's see, he needs to propose his ideas pointed directly to a problem in a project, a practical problem. After he proposes his ideas, he must use the knowledge in his specialised field to compose a good engineering design. After forming the good design, he must be able to analyse his design with the tools he had: is the design going to solve the problem? After analysis is done, he also needs to optimise, use different methods to see which one is the best option to solve the problem. During the process of optimisation, he may discover that the original design may not be the best, then, he need to adjust it. After the adjustment, he may need another analysis. So, as we can see, after we have a problem, idea, design, analysis, optimisation, and if there is another problem, go back to design. It is a process like this, back and forth, back and forth. After all these, after the design is completed, when everyone believes that the current design will solve the problem, then, we document it. So, in the whole process, we need the help of graphics, a great deal of it. Let us see what is the language used by an engineer in such a process. You see, during the stage of idea and design, an engineer need a lot of sketch. Sketch is not just something messy drawn with haste. A sketch helps the engineer to think and communicate as he draws. So it is a tool for speedy exploration to find answers or ideas that may solve our problem. Therefore, I think this is a very important ability for an engineer, especially for the modern engineers. There are many computerised methods of analysis, so the only thing that that makes an engineer irreplaceable by machines is this, the thoughts and creativity for prediction of problems and discovery of solutions. This is the ability a modern engineer need the most. Therefore, I believe that modern engineers must value good sketching skills, which you will gradually learn in this course. I hope that everyone will learn these sketching skills and apply them in real life, not just treating it as a technique, but it is a thinking tool. So you can see here, this is sketching skill. This is one of the courses we offered here at Department of Civil Engineering of National Taiwan University. We asked students to think about how to connect the different spaces of the school campus. As you can see, the students sketch this in a very short time. You can imagine that originally, this sketch might be sketched by pencil, and the student was talking, thinking, and gradually, sketched the ideas on paper. Something wasn't right, erased it and sketched again, Or something was really wrong, after ten minutes, get another piece of paper and start afresh. You can imagine that such a sketch may just take about ten minutes, and you can come up with four to six types possibilities to solve the problem with different engineering concepts. Therefore, we can see that this is indeed a very important tool�C Then, when we design, we need the design drawing. This design drawing will be more precise. For example, this is a 3D design drawing, it has the dimensions, the shapes, the figures of the components of this engineering work. So this design has moved from the idea, how to solve the problem, are we going to use a round shape or a square shape etc, to a real design of what is the approximate dimensions are, what will it probably look like. In this course, we emphasise on the computer drawing of this kind we stressed on the 2D computer drawing, and this is what we call CAD, Computer Aided Drawing 2D CAD is another essential skill for engineers. After he has the concepts, he needs to tell others. his co-workers, people from other fields of engineering, or even the proprietor, he need to tell them what the accurate, precise design looks like. Such engineering graphic is essential. For analysis, we need analytic diagram. This is an example on the blackboard. In the Department of Civil Engineering, we always come across such analytic diagram. It is a simple diagram, but it contains the element of mechanics, the concept and structure of mechanics, even the abstract forces, how they work etc. Among our engineers, we always come across such diagrams, whereby it expresses abstract concepts in it. An engineer needs to familiarise with this kind of presentation. Then, there is optimisation, to optimise we need to make different diagrams very often. This is a good example, you can see here, we made a structure, we have a design for engineering work, and we make a model, we can run some tests. This model you see right now, it may be an actual model or a virtual model. it maybe a model for a pillar, and we are going to keep running tests for different circumstances. Like in this case, our students made a structure of a roof, we will apply different forces and observe its deformation. At this stage, engineers need to make this kind of diagram, and from this diagram, we see which solution is the most suitable one. So even in the last stage, the stage of optimisation. in this stage, we need good diagrams as the resources to make good decisions. Lastly, we need a good engineering drawing. I have collected a very good one here. This is a very ancient design drawing of a bridge, a structural design drawing. Such an ancient document, we can see it today, not just see it, but we can use it today, This bridge maybe a hundred years old, and now we need to do some repairs, so we need the original drawings. and from there, we continue with the design. So the whole thing is very important, this one, the last documentation. This is the precise engineering drawing, and it is saved in our department, we can access it when we need it So this becomes a very essential basis for engineering work. So, engineers, we need to practice all kinds of graphics, practice them well, because this is a language, no matter it is problem analysis, or the collection of documentations, the whole structure is the language of Engineering Graphics, just we communicate in various ways. This course of ours cannot teach you everything, as you can see, this does not sound like traditional Engineering Graphics. So, mostly we will focus on three parts: first is the sketch, that is, the ability to speedily draw your concepts, I do hope that students will be able to acquire such ability in the following weeks. You have a concept, and you are able to draw it. Others tell you a concept or you see a scenario at the site, you are able to draw it in the engineering way. Secondly, there is design. We sketched, we have the concept, then, we can go back home, use the computer and the program, we can use computer-aided drawing to express this concept more accurately. This precision is good enough to be taken directly to the construction site for work to be done. Or now, we have the CAD/CAM, that is, after the CAD file, we can go to a 3D printer to print it out directly. This is another ability I want you to have at the end of the course. Lastly, I also hope this course can teach you the technique of Engineering Graphics to help you produce engineering documentation. This is the official output of the result of your engineering design, and you can eventually produce the documentation. So that's about it. I hope that everyone will learn a lot in this course.