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【正文】 There is a growing: awareness, however, among engineers and in the munity at large that the exponential increase in population and living standards is raising formidable problems in pollution of the environment and the exhaustion of natural resources。 thermodynamics, dealing with the relations among the various forms of heat, energy, and power。Mechanical EngineeringIntroduction to Mechanical Engineering Mechanical engineering is the branch of engineering that deals with machines and the production of power. It is particularly concerned with forces and motion.History of Mechanical EngineeringThe invention of the steam engine in the latter part of the 18th century, providing a key source of power for the Industrial Revolution, gave an enormous impetus to the development of machinery of all types. As a result a new major classification of engineering, separate from civil engineering and dealing with tools and machines, developed, receiving formal recognition in 1847 in the founding of the Institution of Mechanical Engineers in Birmingham, England. Mechanical engineering has evolved from the practice by the mechanic of an art based largely on trial and error to the application by the professional engineer of the scientific method in research, design, and production.The demand for increased efficiency, in the widest sense, is continually raising the quality of work expected from a mechanical engineer and requiring of him a higher degree of education and training. Not only must machines run more economically but capital Costs also must be minimized.Fields of Mechanical EngineeringDevelopment of machines for the production of goods the high material standard of living in the developed countries owes much to the machinery made possible by mechanical engineering. The mechanical engineer continually invents machines to produce goods and develops machine tools of increasing accuracy and plexity to build the machines.The principal lines of development of machinery have been an increase in the speed of operation to obtain high rates of production, improvement in accuracy to obtain quality and economy in the product, and minimization of operating costs. These three requirements have led to the evolution of plex control systems.The most successful production machinery is that in which the mechanical design of the machine is closely integrated with the control system, whether the latter is mechanical or electrical in nature. A modern transfer line (conveyor) for the manufacture of automobile engines is a good example of the mechanization of a plex series of manufacturing processes. Developments are in hand to automate production machinery further, using puters to store and process the vast amount of data required for manufacturing a variety of ponents with a small number of versatile machine tools. One aim is a pletely automated machine shop for batch production, operating on a three shift basis but attended by a staff for only one shift per day.Development of machines for the production of power Production machinery presuppose an ample supply of power. The steam engine provided the first practical means of generating power from heat to augment the old sources of power from muscle, wind, and water One of the first challenges to the new profession of mechanical engineering was to increase thermal efficiencies and power。 automatic control。 lubrication。 there have been eight failures in the last six weeks. Do something about it.On the other hand, the statement of a particular need to be satisfied may be so nebulous and ill defined that a considerable amount of thought and effort is necessary in ( order to state it dearly as a problem requiring a solution. Here are two 1. Lots of people are killed in airplane accidents.2. In big cities there are too many automobiles on the streets and highways.This second type of design situation is characterized by the fact that neither the need nor the problem to be solved has been identified. Note, too, that the situation may contain not one problem but many.We can classify design, too. For instance, we speak of:1. Clothing design 7. Bridge design2. Interior design 8. Computeraided design3. Highway design 9. Heating system design. 4. Landscape design 10. Machine design5. Building design 11. Engineering design6. Ship design 12. Process designIn fact, there are an endless number, since we can classify design according to the particular article or product or according to the professional field,In contrast to scientific or mathematical problems, design problems have no unique answe
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