英语翻译
As we look around us we see a world full of “things”:machines,devices,tools; things that we have designed,built,and used; things made of wood,metals,ceramics,and plastics.We know from experience that some things are better than others; they last longer,cost less,and quieter,look better,or are easier to use.Ideally,however,every such item has been designed according to some set of “functional requirements” as perceived by the designers-that is,it has been designed so as to answer the question,“Exactly what function should it perform?” in the world of engineering,the major function frequently is so support some type of loading due to weight,inertia,pressure,etc.From the beams in our homes to the wings of an airplane,there must be an appropriate melding of materials,dimensions,and fastenings to produce structures that will perform their functions reliably for a reasonable cost over a reasonable lifetime.