软件和软件工程(文献翻译

软件和软件工程(文献翻译内容摘要：

form vacuum tube processors to microelectronic deviced that are capable of processing 200 million include uctions per second .In popular books on “the puter revolution,”Osborne characterized a “new industrial revolution,” Toffer called the advent of microelectronics part of “the third wave of change” in human history , and Naisbitt predicted that the transformation from an industrial society to an “information society” will have a profound impact on our lives. Feigenbaum and McCorduck suggested that information and knowledge will be the focal point for power in the twentyfirst century, and Stoll argued that the “ electronic munity” created by works and software is the key to knowledge interchange throughout the world . As the 1990s began , Toffler described a “power shift” in which old power structures( governmental, educational,industrial,economic,and military) will disintegrate as puters and software lead to a “democratization of knowledge.”depicts the evolution of software within the context of puterbased system application areas. During the early years of puter system development, hardware underwent continual change while software was viewed by many as an afterthought. Computer programming was a seatofthepants art for which few systematic methods existed. Software development was virtually unmanageduntil schedules slipped or costs began to escalate. During this period, a batch orientation was used for most systems. Notable exceptions were interactive systems such as the early American Airlines reservation system and realtime defenseoriented systems such as SAGE. For the most part, however, hardware was dedicated to the Performance ution of a single program that in turn was dedicated to a specific application. During the early years, generalpurpose hardware became monplace. Software,on the other hand,was customdesigned for each application and had a relativelylimited software(.,programs developed to be sold to one or more cunstomers) was in irs infancy . Most software was developed and unltimately used by the same person or anization. You wrote it, you got it running , and if it failed, you fixed it. Because job mobility was low , managers could rest assured that you’d be there when bugs were encountered. Because of this personalized software environment, design was an implicit process performed in one’s head, and text file was often nonexistent. During the early years we learned much about the implementation of puterbased systems, but relatively little about puter system engineering .In fairness , however , we must acknowledge the many outstanding puterbased systems that were developed during this era. Some of these remain in use today and provide landmark achievements that continue to justify admiration. The second era of puter system evolution (Figure ) spanned the decade from the mid1960s to the late 1970s. Multiprogramming and multiuser systems introduced new concepts of humanmachine interaction. Interactive techniques opened a new world of applications and new levels of hardware and software sophistication . Realtime system。