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外 文 专 业 文 章 翻 译 指导老师： 姓 名： 工程中的微型计算机 在过去 25 年间,许多新的计算机功能已经转换为实践社会和行为研究, 计算机在每个方面之内对于社会研究来说发挥了巨大的作用。 包括许多对以前来说不太可能工作，如文本的分析和一些以前不能做到的分析,而这些在数年以前是不可能完成的。 当我们进入新的世纪时候 , 社会科学的水平急剧地加速。直到 19世纪80 年代早期因为价格和当时主流的社会科学家开始打算获得新型的计算机的原因，所以导致普通的微型计算机的性能的发展。这个主意是明显的因为其他的原因, 但是无论如何它是情绪的反应，没有人宣称不需要的学习更多有关计算机的知识。唯一的主要不合适是在人们明确地的基础上为了要快速地发展计算机而要避免荒废的技术。 为了要确定多少学问才是被科学家认可的平均量科学家需要新的微型计算机技术,许多社会的研究员开始找寻一个原始资料帮助找出其中原因，而且使用的主要方法是使用计算机。 这就是我们这本书发 表 关于同志近三年现实表现材料材料类招标技术评分表图表与交易pdf视力表打印pdf用图表说话 pdf 的原因。其他的书籍已经在社会科学的计算机上写出，但是他们容易偏向软件的编程的特性应用。 20世纪70年代的微型计算机发展引起了工程设计的一场革命。在19世纪之初的工业革命宣布了用机械工具代替繁重的体力劳动的机器有了进展。但除了少数例外，这些机器需要人的操作管理，这是因为控制这种机械的动力的问题并不都是简明的。 在20世纪，出现了许多种基于电子、机械、液压和流体原理的自动控制系统。由于系统中的每一元件通常对系统的运转状态只起单一确定的功能，各种类型系统的设计技术是相似的。 微型计算机代表了一种根本不同的系统设计方法。其物理形式是非常简单可靠的，包括一些通用元件，通过编程取得所需的系统功能。控制程序的设计必须给与系统所需的功能作用，它像其他工程类型一样包含“元件”和“组件”。程序或软件，如同物理硬件形成的工程系统，但如果设计正确，是不易出问题的。 可编程系统的设想很早以前就有了，电子计算机已使用了几十年。但是，它的应用得益于大规模集成电路-硅片的发展，从而使生产的计算机变得足够的便宜、耐用且可靠，能够以部件的形式综合到工程设计中去。软件设计技术对计算机科学家来说已是十分清楚的，而且并不奇怪好的工程设计和“软件工程”是好的工程设计的基本条件，我们会看到使用软件的工程设计使系统设计比使用更常规的方法更为简便。 正是由于电子器件技术的发展和计算机技术发展的综合产生了微型计算机。这些技术“汇集起来”形成了今天的电子工业。 从计算机到微型计算机 尽管最早的计算机先于电子学好几十年，电子工业的发展是计算机发展的基础。事实上，对“第一台计算机”的代表的选择主要取决于我们将何种东西看作是计算机，例如一种计算机辅助工具，算盘，在古代就已被人所知了。 布莱斯帕斯卡于1642年发明第一台真正的计算器；这是包含一组齿轮传动轮的纯机械装置，齿轮的分布使任何一齿轮旋转一周就驱动其紧邻的齿轮向左旋转十分之一周。在19世纪前半叶，巴贝奇由机械技术设计了可编程计算机器，尽管我们今天知道这些计算机是不实用的，因为要建造他们需要很精细的工程。20世纪出现了电机计算机，开发用于诸如密码破译、枪的瞄准等特殊的军事任务，但是这些机器速度不高，并迅速被使用热离子管的全电子设计所取代。 二次大战后，民用的计算机被开发来作为一种商务的科学用途的大型昂贵的执行算术运算的机器。热离子管的功耗和使用的不可靠限制了计算机的使用，直至晶体管的出现取代了热离子管，而且新的信息存储技术的采用使得生产的计算机更小更强大。 20世纪60年代目睹了小型计算机的出现，这种计算机很小并且价格低廉至几千英镑，所以可以被较大数量的生产并用于工业控制和实验仪器。当集成电路被采用时，小型计算机就变得更为便宜。随着这些电路变得更加复杂，建造功能化计算机所需要的集成电路数量则下降，直至可能只用一块或两块印刷电路板构成小型计算机，这些小型计算机使得在设计、开发和委托加工工具有大量电子逻辑的 方案 气瓶 现场处置方案 .pdf气瓶 现场处置方案 .doc见习基地管理方案.doc关于群访事件的化解方案建筑工地扬尘治理专项方案下载 时，所需的时间就大为减少。 集成电路技术的更新发展促使了微型计算机的出现，也就是用相对较少量的集成电路元件构成了小计算机。事实上一个完整的计算机可用一个芯片做出。在任一计算机中，其核心是中央处理器即CPU，而微型计算机的核心是微处理器或MPU，它是用一个硅片制成的CPU。它的处理能力比早先的巨大芯片还要强，并且对仅仅作为另一种工程部件来说，已足够强大。 微型计算机被设想为能以非常灵活的方式进行编程的装置，通过一组电子指令 清单 安全隐患排查清单下载最新工程量清单计量规则下载程序清单下载家私清单下载送货清单下载 就能给出几乎任何所希望的功效。使用计算机会涉及在生成指令清单时的编程技巧以及常用的电子和机械设计技术。正如它的名字所指示的，微型计算机以常用计算机十分相同的方法组成；事实上，它可看作是从最早的计算机“进化”的“自然”结果。 微型计算机的优缺点 第一个优点已经提到过了，就是电子系统的大规模集成已经降低了所用的元件数量，促使系统的总体可靠性的提高和装配费用的降低。由于大规模集成引起的尺寸减小意味着基于微型计算机的设备功能通常要小得多，轻的多，并且比用旧技术制成的设备要更为强大。 由于微型计算机是通用设备，能够大量的从生产线上产生，所以与构成同样复杂性系统的常规方法相比，会使单位成本低得多。这种 标准 excel标准偏差excel标准偏差函数exl标准差函数国标检验抽样标准表免费下载红头文件格式标准下载 化可扩大到安装集成电路的印刷电路，这样就能以相当合理的价格购到用单位印数电路板形成的非常复杂的微型计算机的微机系统。而且标准元件的使用使标准测试附件在故障诊断中的应用成为可能。 是程序限定了微机化系统的功能，通常也正是在这个程序环境下，大多数的系统设计得以开展。在软件工程设计中，工程师会遇到许多熟悉的概念，例如模块设计的重要性，以及可测试性和可维护性设计的必要性。事实上，假如某些系统错误可被设计者所预见，微机在系统中的存在就使得错误查找问题变得容易，这些因为微机可用来诊断错误的确切性。但是，基于时间的错误是不容易探测的，这些错误可能要运行许多小时后才会变得清楚。 到此，微机看起来给了工程人员某些万灵药，但是不幸得是在使用微机时也会引发某些不利因素。首先是纯电子系统仍具有吸引力；微机逻辑比硬件连接的电子逻辑大约慢100倍。在许多应用中，例如具有机械接口的场合，这是不重要的，因为响应速度是由外部因素而不是微机本身速度所限制的。 在不良的微机系统中，错误的查找问题就更加严重。这种错误可能存在于电子硬件中，或者是由于编程错误，而涉及硬软件交互的错误则特别难以克服。常用的错误查找技术和仪器，如示波器，常常对他们无能为力，但幸运的是用于错误定位和辨别的方法已经被开发出来。 附录：英文原件 Microcomputer in engineering During the past 25 years many new computer capabilities have transformed the practice of social and behavioral research, Computer continue to be drawn into every facet of social research. including such unlikely tasks as textual analysis and field note-taking, which were totally untouched by computers only a few years ago. This transformation of the social sciences dramatically accelerated when we entered the new century. It was not until the early 1980s that the price and performance of the average microcomputer had evolved to the point when typical social scientists began to comtenpalte acquiring desktop computers. Such idear was more obtrsive for some than for others, but whatever the emotional reaction, no one claim ed immunity from the need to learn more about computers. The only major disagreement was over what people specifically need to know in order to avoid obsolescence from the rapidly advancing technology of computing. In order to decide how much learning is needed by the average social scientist to harness the power of the new microcomputer technology, many social researchers began looking for a sourcebook to help locate and evalutate the principal ways computers can be used. It is this need to which we address this book .Other books have been written on computers in the social sciences, but they tend to merely explain how specific soft ware is used. The development of the microcomputer during the 1970s brought about a revolution in engineering design. The industrial revolution at the turn of the nineteenth century heralded the development of machines which could replace physical drudgery by mechanical means. Apart from a few exceptions, however, these machines required manual supervision because the problem of controlling this mechanical power was not at all straightforward. Many types of automatic control systems have appeared during the twentieth century, based on electronic, mechanical, hydraulic, and fluidic principles. In each case the design techniques have been similar because each component of the system usually contributes a single well defined function to the system behavior. The microcomputer represents a fundamentally different approach to the design of a system. Its physical form is quite simple and reliable, consisting of a few general-purpose elements which can be programmed to make the system function as required. It is the controlling program which must be designed to give the system the required behavior, and which will contain components and “subassemblies” just like any other kind of engineering. The program, or software, is just of the engineered system as the physical hardware, but it is much less susceptible to failure, provided that it is designed properly. The idea of programmed systems is not new; electronic computers have been in existence for many years. However, it has taken the development of the large scale integrated circuit-the silicon chip-to produce computers which are cheap, rugged, and reliable enough to be incorporated into engineering designs as components. The techniques of software design are well known to computer scientists and it is not surprising that the principles of good engineering design and “software engineering” are essentially those of good engineering design. We shall see that engineering design using software allows systems to be designed more easily than using more conventional techniques. It is the combination of developments in electronic device technology with those in computer technology which has enabled the microcomputer to be produced, and these technologies have “converged” to produce the microcomputer industry. Which we see today. FROM COMPUTER TO microcomputer The development of electronic technology has been the basis of the development of the computer, although the earliest computer antedates electronics by many decades. In fact the choice of candidate for “first computer” depends very much upon what we choose to regard as a computer; for example one calculating aid, the abacus, has been knows since antiquity. Blaise Pascal invented the first real calculating machine in 1642; this was a purely mechanical device consisting of a set of geared wheels arranged so that a complete revolution of any wheel rotated the wheel immediately to its left through one-tenth of a revolution . In the first half of the nineteenth century Babbage designed programmable calculation “engines” using mechanical techniques, although computers as we know them today were impractical because of the precision engineering required to construct them. The twentieth century saw the arrival of electromechanical computers, which were developed for special military tasks such as code-breaking and gun-aiming. However, these lacked speed and they were soon superseded by full electronic designs using thermionic valves. After the Second World War Ⅱ the computer was developed for civilian use as a large and expensive arithmetic-performing machine for business and scientific purpose. The power consumption and unreliability of valves limited the use fullness of computers until valves were ousted by the introduction of the transistor, and new information of transistor, and new information storage techniques appeared which allowed smaller and more powerful computer to be produced. The 1960s saw the introduction of the minicomputer which was small and cheap enough at a few thousands of pounds-or dollars-to be produced in relative large numbers for industrial control and laboratory instrumentation purposes. The minicomputer became yet cheaper when integrated circuits were introduced. As these circuits became more complex the number of integrated circuit required to construct a functioning computer fell, until simple minicomputers using only one or two printed circuit boards became possible. These minicomputers enabled significant reductions to be made in the time needed to design, develop, and commission many projects requiring large amount of electronic logic. More recent develop in integrated circuit technology have led to the introduction of microcomputer, small computers fabricated using relatively few integrated circuit components. In fact an entire microcomputer can be made as a single chip. At the heart of any computer is a Central Processing Unit or CPU, and the corresponding heart of the microcomputer is the microprocessor, which is simply a CPU implemented on a silicon chip. Its processing power is greater than that of its giant predecessors and yet it is cheap and robust enough to be treated as simply another engineering component. The microcomputer was conceived as a device which could be programmed in a very flexible fashion to give almost any desired behavior by means of a list of electronic instructions. Using a microcomputer involves programmed skill in producing these lists of instructions as well as more conventional electronic and mechanical design techniques. As its name suggests, the microcomputer is organized in much the same way as a conventional computer; indeed, it may be regarded as the “natural” outcome of the “evolution” of the computer from its earliest days. The Advantages and Disadvantages of microcomputer system The first advantage has already been mentioned; the large-scale integration of electronic systems has reduced the number of components which are used, leading to an increase in the overall reliability of the system and a reduction in assembly costs. The decrease in size which results from large-scale integration means that equipment based on microcomputers is usually much smaller, lighter, and more robust than that using older technologies. Microcomputer can be made in large quantities because they are general purpose devices, and this leads to a much lower unit cost when compared with more conventional methods of producing system with similar complexity. This standardization can be extended to the printed circuits on which the integrated circuits are mounted, and very sophisticated microcomputer systems can be purchased as single printed circuit boards at quite reasonable cost. The use of standard components also offers the possibility of standard test fixtures for use in fault diagnosis. It is the program which defines the function of a microcomputer based system and usually it is in this program that most of the system design is carried out. Many concepts which ate similar to the engineers are found in software engineering, such as the need for modular design and the need to design for testability and maintainability. In fact, the presence of a microcomputer in a system can case the problem of fault finding if the possibility of such faults has been anticipated by the designer, since the microcomputer may be used to provide diagnose the precise nature of the fault. However, time dependent faults are less easily detected, and may become apparent only when the equipment has been operating for many hours. The microcomputer might appear at this point to have been presented as something of an engineer’s panacea, but unfortunately there are also some disadvantages which arise from using a microcomputer. The first is mainly of interest in purely electronic systems; microcomputer logic is slower than hardwired electronic logic by a factor of perhaps 100. In many applications, for example those which have mechanical interfaces, this is not important because the speed of response is limited by external factors rather than the speed of the microcomputer itself. The problem of fault finding in a malfunctioning microcomputer system is more serious. The fault could be in the electronic hardware, or it might be due to a programming error, and faults which involve interactions between hardware and software are especially inscrutable. Conventional fault-finding techniques and instruments such as oscilloscopes are frequently useless in such cases, but fortunately methods for locating and identifying faults have been developed. INTRODUCTION TO MICROPROCESSORS 作者：Herbert Brunner 出版商：Reston publishing company, inc. PAGE 2