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计算机专业外文资料翻译----微机发展简史

计算机专业外文资料翻译----微机发展简史
计算机专业外文资料翻译----微机发展简史

附录外文文献及翻译

Progress in computers

The first stored program computers began to work around 1950. The one we built in Cambridge, the EDSAC was first used in the summer of 1949.

These early experimental computers were built by people like myself with varying backgrounds. We all had extensive experience in electronic engineering and were confident that that experience would standus in good stead. This proved true, although we had some new things to learn. The most important of these was that transients must be treated correctly; what would cause a harmless flash on the screen of a television set could lead to a serious error in a computer.

As far as computing circuits were concerned, we found ourselves with an embarrass de riches. For example, we could use vacuum tube diodes for gates as we did in the EDSAC or pentodes with control signals on both grids, a system widely used elsewhere. This sort of choice persisted and the term famillogic came into use. Those who have worked in the computer field will remember TTL, ECL and CMOS. Of these, CMOS has now become dominant.

In those early years, the IEE was still dominated by power engineering and we had to fight a number of major battles in order to get radio engineering along with the rapidly developing subject of electronics. dubbed in the IEE light current electrical engineering. properlyrecognized as an activity in its own right. I remember that we had some difficulty in organizing a co nference because the power engineers? ways of doing things were not our ways. A minor source of irritation was that all IEE published papers were expected to start with a lengthy statement of earlier practice, something difficult to do when there was no earlier practice

Consolidation in the 1960s

By the late 50s or early 1960s, the heroic pioneering stage was over and the computer field was starting up in real earnest. The number of computers in the world had increased and they were much more reliable than the very early ones . To those years we can ascribe the first steps in high level languages and the first operating systems. Experimental time-sharing was beginning, and ultimately computer graphics was to come along.

Above all, transistors began to replace vacuum tubes. This change presented a formidable challenge to the engineers of the day. They had to forget what they knew about circuits and start again. It can only be said that they measured up superbly well to the challenge and that the change could not have gone more smoothly.

Soon it was found possible to put more than one transistor on the same bit of silicon, and this was the beginning of integrated circuits. As time went on, a sufficient level of integration was reached for one chip to accommodate enough transistors for a small number of gates or flip flops. This led to a range of chips known as the 7400 series. The gates and flip flops were independent of one another and each had its own pins. They could be connected by off-chip wiring to make a computer or anything else.

These chips made a new kind of computer possible. It was called a minicomputer. It was something less that a mainframe, but still very powerful, and much more affordable. Instead of having one expensive mainframe for the whole organization, a business or a university was able to have a minicomputer for each major department.

Before long minicomputers began to spread and become more powerful. The world was hungry for computing power and it had been very frustrating for industry not to be able to supply it on the scale

required and at a reasonable cost. Minicomputers transformed the situation.

The fall in the cost of computing did not start with the minicomputer; it had always been that way. This was what I meant when I referred in my abstract to inflation in the computer industry …going the other way?. As time goes on people get more for their money, not less.

Research in Computer Hardware.

The time that I am describing was a wonderful one for research in computer hardware. The user of the 7400 series could work at the gate and flip-flop level and yet the overall level of integration was sufficient to give a degree of reliability far above that of discreet transistors. The researcher, in a university orelsewhere, could build any digital device that a fertile imagination could conjure up. In the Computer Laboratory we built the Cambridge CAP, a full-scaleminicomputer with fancy capability logic.

The 7400 series was still going strong in the mid 1970s and was used for the Cambridge Ring, a pioneering wide-band local area network. Publication of the design study for the Ring came just before the announcement of the Ethernet. Until these two systems appeared, users had mostly been content with teletype-based local area networks. Rings need high reliability because, as the pulses go repeatedly round the ring, they must be continually amplified and regenerated. It was the high reliability provided by the 7400 series of chips that gave us the courage needed to embark on the project for the Cambridge Ring.

The RISC Movement and Its Aftermath

Early computers had simple instruction sets. As time went on designers of commercially available machines added additional features which they thought would improve performance. Few comparative measureme nts were done and on the whole the choice of features depended upon the designer?s intuition.

In 1980, the RISC movement that was to change all this broke on the world. The movement opened with a paper by Patterson and ditzy entitled The Case for the Reduced Instructions Set Computer.

Apart from leading to a striking acronym, this title conveys little of the insights into instruction set design which went with the RISC movement, in particular the way it facilitated pipelining, a system whereby several instructions may be in different stages of execution within the processor at the same time. Pipelining was not new, but it was new for small computers

The RISC movement benefited greatly from methods which had recently become available for estimating the performance to be expected from a computer design without actually implementing it. I refer to the use of a powerful existing computer to simulate the new design. By the use of simulation, RISC advocates were able to predict with some confidence that a good RISC design would be able to out-perform the best conventional computers using the same circuit technology. This prediction was ultimately born out in practice.

Simulation made rapid progress and soon came into universal use by computer designers. In consequence, computer design has become more of a science and less of an art. Today, designers expect to have a roomful of, computers available to do their simulations, not just one. They refer to such a roomful by the attractive name of computer farm.

The x86 Instruction Set

Little is now heard of pre-RISC instruction sets with one major exception, namely that of the Intel 8086 and its progeny, collectively referred to as x86. This has become the dominant instruction set and the RISC instruction sets that originally had a considerable measure of success are having to put up a hard fight for survival.

This dominance of x86 disappoints people like myself who come from the research wings. both academic and industrial. of the computer field. No doubt, business considerations have a lot to do with the survival of x86, but there are other reasons as well. However much we research oriented people would like

to think otherwise. high level languages have not yet eliminated the use of machine code altogether. We need to keep reminding ourselves that there is much to be said for strict binary compatibility with previous usage when that can be attained. Nevertheless, things might have been different if Intel?s major attempt to produce a good RISC chip had been more successful. I am referring to the i860 (not the i960, which was something different). In many ways the i860 was an excellent chip, but its software interface did not fit it to be used in aworkstation.

There is an interesting sting in the tail of this apparently easy triumph of the x86 instruction set. It proved impossible to match the steadily increasing speed of RISC processors by direct implementation ofthe x86 instruction set as had been done in the past. Instead, designers took a leaf out of the RISC book; although it is not obvious, on the surface, a modern x86 processor chip contains hidden within it a RISC-style processor with its own internal RISC coding. The incoming x86 code is, after suitable massaging, converted into this internal code and handed over to the RISC processor where the critical execution is performed. In this summing up of the RISC movement, I rely heavily on the latest edition of Hennessy and Patterson?s books on computer design as my supporting authority; see in particular Computer Architecture, third edition, 2003, pp 146, 151-4, 157-8.

The IA-64 instruction set.

Some time ago, Intel and Hewlett-Packard introduced the IA-64 instruction set. This was primarily intended to meet a generally recognized need for a 64 bit address space. In this, it followed the lead of the designers of the MIPS R4000 and Alpha. However one would have thought that Intel would have stressed compatibility with the x86; the puzzle is that they did the exact opposite.

Moreover, built into the design of IA-64 is a feature known as predication which makes it incompatible in a major way with all other instruction sets. In particular, it needs 6 extra bits with each instruction. This upsets the traditional balance between instruction word length and information content, and it changes significantly the brief of the compiler writer.

In spite of having an entirely new instruction set, Intel made the puzzling claim that chips based on IA-64 would be compatible with earlier x86 chips. It was hard to see exactly what was meant.

Chips for the latest IA-64 processor, namely, the Itanium, appear to have special hardware for compatibility. Even so, x86 code runs very slowly.

Because of the above complications, implementation of IA-64 requires a larger chip than is required for more conventional instruction sets. This in turn implies a higher cost. Such at any rate, is the received wisdom, and, as a general principle, it was repeated as such by Gordon Moore when he visited Cambridge recently to open the Betty and Gordon Moore Library. I have, however, heard it said that the matter appears differently from within Intel. This I do not understand. But I am very ready to admit that I am completely out of my depth as regards the economics of the semiconductor industry.

Shortage of Electrons

Although shortage of electrons has not so far appeared as an obvious limitation, in the long term it may become so. Perhaps this is where the exploitation of non-conventional CMOS will lead us. However, some interesting work has been done. notably by HuronAmend and his team working in the Cavendish Laboratory. on the direct development of structures in which a single electron more or less makes the difference between a zero and a one. However very little progress has been made towards practical devices that could lead to the construction of a computer. Even with exceptionally good luck, many tens of years must inevitably elapse before a working computer based on single electron effects can be contemplated.

微机发展简史

第一台存储程序的计算开始出现于1950前后,它就是1949年夏天在剑桥大学,我们创造的延迟存储自动电子计算机(EDSAC)。

最初实验用的计算机是由象我一样有着广博知识的人构造的。我们在电子工程方面都有着丰富的经验,并且我们深信这些经验对我们大有裨益。后来,被证明是正确的,尽管我们也要学习很多新东西。最重要的是瞬态一定要小心应付,虽然它只会在电视机的荧幕上一起一个无害的闪光,但是在计算机上这将导致一系列的错误。

在电路的设计过程中,我们经常陷入两难的境地。举例来说,我可以使用真空二级管做为门电路,就象在EDSAC中一样,或者在两个栅格之间用带控制信号的五级管,这被广泛用于其他系统设计,这类的选择一直在持续着直到逻辑门电路开始应用。在计算机领域工作的人都应该记得TTL,ECL和CMOS,到目前为止,CMOS已经占据了主导地位。

在最初的几年,IEE(电子工程师协会)仍然由动力工程占据主导地位。为了让IEE 认识到无线工程和快速发展的电子工程并行发展是它自己的一项权利,我们不得不面对一些障碍。由于动力工程师们做事的方式与我们不同,我们也遇到了许多困难。让人有些愤怒的是,所有的IEE出版的论文都被期望以冗长的早期研究的陈述开头,无非是些在早期阶段由于没有太多经验而遇到的困难之类的陈述。

60年代的巩固阶段

60年代初,个人英雄时代结束了,计算机真正引起了重视。世界上的计算机数量已经增加了许多,并且性能比以前更加可靠。这些我认为归因与高级语言的起步和第一个操作系统的诞生。分时系统开始起步,并且计算机图形学随之而来。

综上所述,晶体管开始代替正空管。这个变化对当时的工程师们是个不可回避的挑战。他们必须忘记他们熟悉的电路重新开始。只能说他们鼓起勇气接受了挑战,尽管这个转变并不会一帆风顺。

小规模集成电路和小型机

很快,在一个硅片上可以放不止一个晶体管,由此集成电路诞生了。随着时间的推移,一个片子能够容纳的最大数量的晶体管或稍微少些的逻辑门和翻转门集成度达到了一个最大限度。由现了我们所知道7400系列微机。每个门电路或翻转电路是相互独立的并且有自己的引脚。他们可通过导线连接在一起,作成一个计算机或其他的东西。现了我们所知道7400系列微机。每个门电路或翻转电路是相互独立的并且有自己的引脚。他们可通过导线连接在一起,作成一个计算机或其他的东西。

这些芯片为制造一种新的计算机提供了可能。它被称为小型机。他比大型机稍逊,但功能强大,并且更能让人负担的起。一个商业部门或大学有能力拥有一台小型机而不是得到一台大型组织所需昂贵的大型机。

随着微机的开始流行并且功能的完善,世界急切获得它的计算能力但总是由于工业上不能规模供应和它可观的价格而受到挫折。微机的出现解决了这个局面。

计算消耗的下降并非起源与微机,它本来就应该是那个样子。这就是我在概要中提到的“通货膨胀”在计算机工业中走上了歧途之说。随着时间的推移,人们比他们付出的金钱得到的更多。

硬件的研究

我所描述的时代对于从事计算机硬件研究的人们是令人惊奇的时代。7400系列的用户能够工作在逻辑门和开关级别并且芯片的集成度可靠性比单独晶体管高很多。大学或各地的研究者,可以充分发挥他们的想象力构造任何微机可以连接的数字设备。在剑桥大学实验室力,我们构造了CAP,一个有令人惊奇逻辑能力的微机。

7400在70年代中期还不断发展壮大,并且被宽带局域网的先驱组织Cambridge Ring所采用。令牌环设计研究的发表先于以太网。在这两种系统出现之前,人们大多满足于基于电报交换机的本

地局域网。

令牌环网需要高可靠性,由于脉冲在令牌环中传递,他们必须不断的被放大并且再生。是7400的高可靠性给了我们勇气,使得我们着手Cambridge Ring.项目。

精简指令计算机的诞生

早期的计算机有简单的指令集,随着时间的推移,商业用微机的设计者增加了另外的他们认为可以微机性能的特性。很少的测试方法被建立,总的来说特性的选取很大程度上依赖于设计者的直觉。1980年,RISC运动改变了微机世界。该运动是由Patterson 和Ditzel发表了一篇命名为精简指令计算机的情况论文而引起的。

除了RISC这个引人注目缩略词外,这个标题传达了一些指令集合设计的见解,随之引发了RISC 运动。从某种意义上说,它推动了线程的发展,在处理器中,同一时间有几个指令在不同的执行阶段称为线程。线程不是个新概念,但是它对微机来说是从未有过的。

RISC受益于一个最近的可用的方法的诞生,该方法使估计计算机性能成为可能而不去真正实现该微机的设计。我的意思是说利用目前存在的功能强大的计算机去模拟新的设计。通过模拟该设计,RISC的提倡者能够有信心的预言,一台使用和传统计算机相同电路的RISC计算机可以和传统的最好的计算机有同样的性能。

模拟仿真加快了开发进度并且被计算机设计者广泛采用。随后,计算机设计者变的多些可理性少了一些艺术性。今天,设计者们希望有满屋可用计算机做他们的仿真,而不只是一台。

x86指令集

除非出现很大意外,要不很少听到有计算机使用早期的RISC指令集了。INTEL 8086及其后裔都与x86密切相关。x86构架已经占据了计算机核心指令集的主导地位。被认为是相当成功的RISC 指令集现在的生存空间越来越小了。

对于我们这些从事计算机学术研究的人,x86的统治地位让我们感到失望。毫无疑问,商业上对于x86的生存会有更多的考虑,但是这里还有很多原因,尽管我们多么希望人们考虑其他的方面。高级语言并没有完全消除对机器原始编码的的使用。我们仍需要不断提醒我们自己:我们应该严格的与先前的应用在机器层面上保持兼容。然而,情况也许有所不同,如果Intel的主要目的是为是生产一个好的RISC芯片。有一个已经取得了更大的成功,我所说的i860(不是i960,它们有一些不同)。从许多方面来说,i860是个卓越的芯片,但是它的软件借口不适合在工作站上应用。对于x86取得胜利的最后有一件有意思的事情。直接应用先前x86的实现方式对于满足RISC处理器的持续增长的速度要求,是不可能的。因此,设计者们没有完全实现RISC指令集,尽管这不是很明显。表面上,一片现代的x86芯片包含了隐藏实现的部分,好象和实现RISC指令集的芯片一样。当致命的异常发生时,x86引入的代码是,经过适当的篡改后,被转化为它的内部代码并且被RISC芯片处理。

对于以上RISC运动的总结,我非常信赖最新版本的哈里斯和培生出版社的有关计算机设计的书籍。请参考特殊计算机体系构造,第三版,2003,P146,151-4,157-8

IA-64指令集

很久以前,Intel 和Hewlett-Packard引进了IA-64指令集。这最初主要是为了满足通常的64位地址空间问题。在这种情况下,随后出现了MIPS R4000和Alpha。然而,人们普遍认为Intel应该与x86构架保持兼容,可令人疑惑的是恰恰相反。

进一步说,IA-64的设计与其他所有的指令集在主要实现方式上有所不同。特别的,每条指令它需要附加的6位。这打乱了传统的在指令字长和信息内容的平衡,并且它改变了编译器作者的原先的大纲。

尽管IA-64是个全新的指令集,但Intel发表了一个令人困惑的声明:基于IA-64的芯片将与早期的x86芯片保持兼容。很难弄懂它所指的是什么。

最新的称为Itaninu IA-64处理器显然需要特殊的兼容性的硬件,尽管如此,x86编码运行的相

当慢。

由于以上的复杂因素,IA-64的实现需要更大的体积相对与传统的指令集,这暗示着更大的消耗。因此,在任何情况下,作为常识和一般性的标准,Gordon Moore在访问剑桥最近开放的Betty and Gordon Moore 图书馆时所反复强调。在听到他说问题出现在Intel内部也许有所不同,我很不理解。但是我已经作好了准备,去接受这样的事实,我已经完全不了解半导体经济学了。

电子的不足

尽管目前为止,电子每表现出明显的不足,然而从长远看来,它最终会不能满足要求。也许这是我们开发非传统CMOS管的原因。在Cavendish实验室里,HaroonAmed已经作了很多有意义的工作,他们想通过一个单独电子或多或少的表现出0和1的区别。然而对于构造实用的计算机设备只取得了一点点进展。也许由于偶然的好运气,数十年后一台基于一个单独电子的计算机也许是可以实现的

计算机专业外文文献及翻译

微软Visual Studio 1微软Visual Studio Visual Studio 是微软公司推出的开发环境,Visual Studio可以用来创建Windows平台下的Windows应用程序和网络应用程序,也可以用来创建网络服务、智能设备应用程序和Office 插件。Visual Studio是一个来自微软的集成开发环境IDE,它可以用来开发由微软视窗,视窗手机,Windows CE、.NET框架、.NET精简框架和微软的Silverlight支持的控制台和图形用户界面的应用程序以及Windows窗体应用程序,网站,Web应用程序和网络服务中的本地代码连同托管代码。 Visual Studio包含一个由智能感知和代码重构支持的代码编辑器。集成的调试工作既作为一个源代码级调试器又可以作为一台机器级调试器。其他内置工具包括一个窗体设计的GUI应用程序,网页设计师,类设计师,数据库架构设计师。它有几乎各个层面的插件增强功能,包括增加对支持源代码控制系统(如Subversion和Visual SourceSafe)并添加新的工具集设计和可视化编辑器,如特定于域的语言或用于其他方面的软件开发生命周期的工具(例如Team Foundation Server的客户端:团队资源管理器)。 Visual Studio支持不同的编程语言的服务方式的语言,它允许代码编辑器和调试器(在不同程度上)支持几乎所有的编程语言,提供了一个语言特定服务的存在。内置的语言中包括C/C + +中(通过Visual C++),https://www.doczj.com/doc/4614560049.html,(通过Visual https://www.doczj.com/doc/4614560049.html,),C#中(通过Visual C#)和F#(作为Visual Studio 2010),为支持其他语言,如M,Python,和Ruby等,可通过安装单独的语言服务。它也支持的 XML/XSLT,HTML/XHTML ,JavaScript和CSS.为特定用户提供服务的Visual Studio也是存在的:微软Visual Basic,Visual J#、Visual C#和Visual C++。 微软提供了“直通车”的Visual Studio 2010组件的Visual Basic和Visual C#和Visual C + +,和Visual Web Developer版本,不需任何费用。Visual Studio 2010、2008年和2005专业版,以及Visual Studio 2005的特定语言版本(Visual Basic、C++、C#、J#),通过微软的下载DreamSpark计划,对学生免费。 2架构 Visual Studio不支持任何编程语言,解决方案或工具本质。相反,它允许插入各种功能。特定的功能是作为一个VS压缩包的代码。安装时,这个功能可以从服务器得到。IDE提供三项服务:SVsSolution,它提供了能够列举的项目和解决方案; SVsUIShell,它提供了窗口和用户界面功能(包括标签,工具栏和工具窗口)和SVsShell,它处理VS压缩包的注册。此外,IDE还可以负责协调和服务之间实现通信。所有的编辑器,设计器,项目类型和其他工具都是VS压缩包存在。Visual Studio 使用COM访问VSPackage。在Visual Studio SDK中还包括了管理软件包框架(MPF),这是一套管理的允许在写的CLI兼容的语言的任何围绕COM的接口。然而,MPF并不提供所有的Visual Studio COM 功能。

计算机专业毕业设计说明书外文翻译(中英对照)

Talking about security loopholes Richard S. Kraus reference to the core network security business objective is to protect the sustainability of the system and data security, This two of the main threats come from the worm outbreaks, hacking attacks, denial of service attacks, Trojan horse. Worms, hacker attacks problems and loopholes closely linked to, if there is major security loopholes have emerged, the entire Internet will be faced with a major challenge. While traditional Trojan and little security loopholes, but recently many Trojan are clever use of the IE loophole let you browse the website at unknowingly were on the move. Security loopholes in the definition of a lot, I have here is a popular saying: can be used to stem the "thought" can not do, and are safety-related deficiencies. This shortcoming can be a matter of design, code realization of the problem. Different perspective of security loo phole s In the classification of a specific procedure is safe from the many loopholes in classification. 1. Classification from the user groups: ● Public loopholes in the software category. If the loopholes in Windows, IE loophole, and so on. ● specialized software loophole. If Oracle loopholes, Apach e,

外文翻译

Load and Ultimate Moment of Prestressed Concrete Action Under Overload-Cracking Load It has been shown that a variation in the external load acting on a prestressed beam results in a change in the location of the pressure line for beams in the elastic range.This is a fundamental principle of prestressed construction.In a normal prestressed beam,this shift in the location of the pressure line continues at a relatively uniform rate,as the external load is increased,to the point where cracks develop in the tension fiber.After the cracking load has been exceeded,the rate of movement in the pressure line decreases as additional load is applied,and a significant increase in the stress in the prestressing tendon and the resultant concrete force begins to take place.This change in the action of the internal moment continues until all movement of the pressure line ceases.The moment caused by loads that are applied thereafter is offset entirely by a corresponding and proportional change in the internal forces,just as in reinforced-concrete construction.This fact,that the load in the elastic range and the plastic range is carried by actions that are fundamentally different,is very significant and renders strength computations essential for all designs in order to ensure that adequate safety factors exist.This is true even though the stresses in the elastic range may conform to a recognized elastic design criterion. It should be noted that the load deflection curve is close to a straight line up to the cracking load and that the curve becomes progressively more curved as the load is increased above the cracking load.The curvature of the load-deflection curve for loads over the cracking load is due to the change in the basic internal resisting moment action that counteracts the applied loads,as described above,as well as to plastic strains that begin to take place in the steel and the concrete when stressed to high levels. In some structures it may be essential that the flexural members remain crack free even under significant overloads.This may be due to the structures’being exposed to exceptionally corrosive atmospheres during their useful life.In designing prestressed members to be used in special structures of this type,it may be necessary to compute the load that causes cracking of the tensile flange,in order to ensure that adequate safety against cracking is provided by the design.The computation of the moment that will cause cracking is also necessary to ensure compliance with some design criteria. Many tests have demonstrated that the load-deflection curves of prestressed beams are approximately linear up to and slightly in excess of the load that causes the first cracks in the tensile flange.(The linearity is a function of the rate at which the load is applied.)For this reason,normal elastic-design relationships can be used in computing the cracking load by simply determining the load that results in a net tensile stress in the tensile flange(prestress minus the effects of the applied loads)that is equal to the tensile strength of the concrete.It is customary to assume that the flexural tensile strength of the concrete is equal to the modulus of rupture of the

外文资料及其翻译

A Wavelet Based Approach for Fast Detection of Internal Fault in Power Transformers The power transformer is one of the most expensive elements of power system and its protection is an essential part of the overall system protection strategy. The differential protection provides the best protection for power transformer. Its operation principle is based on this point that the differential current during an internal fault is higher than normal condition. But, a large transient current (inrush current) can cause mal-operation of differential relays. Then, studies for the improvement of the transformer protection have focused on discrimination between internal short circuit faults and inrush currents in transformers. The magnetizing inrush current has a large second order harmonic component in comparison to internal faults. Therefore , some transformer protection systems are designed to halt operating during the inrush current by sensing this large second order harmonic. The second harmonic component in the magnetizing inrush currents tend to be relatively small in modern large power transformers because of improvements in the power transformer core materials. Also , it has been seen that the fault current can contain higher second order harmonics than the inrush current due to nonlinear fault resistance, CT saturation .the distributed capacitance in the transmission line, which transformer is connected to, or due to the use of extra high voltage underground cables. Various methods have been suggested for overcoming this protection system mal-operation. This paper presents a wavelet based method for discrimination among inrush current, internal short circuit ,external short circuit and energizing and it is not affected by CT saturation and it is able to detect internal faults while transformer energization. Unlike Artificial Neural Network and Fuzzy logic based algorithms. This approach is not system dependent. The operating time of the scheme is less than 10ms. The Daubechies mother wavelet is used with a sample rate of 5 kHz. Then , the differential currents of the three phases are decomposed into two details and only the second level will be considered by using db5 mother wavelet. Discrete Wavelet Transform The wavelet transform is a powerful tool to extract information from the non-stationary signals simultaneously in both time and frequency domains. The ability of the wavelet transform to focus on short time intervals for high-frequency components and long intervals for low-frequency components improves the analysis

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外文文献翻译(译成中文2000字左右): As research laboratories become more automated,new problems are arising for laboratory managers.Rarely does a laboratory purchase all of its automation from a single equipment vendor. As a result,managers are forced to spend money training their users on numerous different software packages while purchasing support contracts for each. This suggests a problem of scalability. In the ideal world,managers could use the same software package to control systems of any size; from single instruments such as pipettors or readers to large robotic systems with up to hundreds of instruments. If such a software package existed, managers would only have to train users on one platform and would be able to source software support from a single vendor. If automation software is written to be scalable, it must also be flexible. Having a platform that can control systems of any size is far less valuable if the end user cannot control every device type they need to use. Similarly, if the software cannot connect to the customer’s Laboratory Information Management System (LIMS) database,it is of limited usefulness. The ideal automation software platform must therefore have an open architecture to provide such connectivity. Two strong reasons to automate a laboratory are increased throughput and improved robustness. It does not make sense to purchase high-speed automation if the controlling software does not maximize throughput of the system. The ideal automation software, therefore, would make use of redundant devices in the system to increase throughput. For example, let us assume that a plate-reading step is the slowest task in a given method. It would make that if the system operator connected another identical reader into the system, the controller software should be able to use both readers, cutting the total throughput time of the reading step in half. While resource pooling provides a clear throughput advantage, it can also be used to make the system more robust. For example, if one of the two readers were to experience some sort of error, the controlling software should be smart enough to route all samples to the working reader without taking the entire system offline. Now that one embodiment of an ideal automation control platform has been described let us see how the use of C++ helps achieving this ideal possible. DISCUSSION C++: An Object-Oriented Language Developed in 1983 by BjarneStroustrup of Bell Labs,C++ helped propel the concept of object-oriented programming into the mainstream.The term ‘‘object-oriented programming language’’ is a familiar phrase that has been in use for decades. But what does it mean? And why is it relevant for automation software? Essentially, a language that is object-oriented provides three important programming mechanisms:

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计算机外文资料翻译---Visual Basic简介

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文献翻译 原文 Combining JSP and Servlets The technology of JSP and Servlet is the most important technology which use Java technology to exploit request of server, and it is also the standard which exploit business application .Java developers prefer to use it for a variety of reasons, one of which is already familiar with the Java language for the development of this technology are easy to learn Java to the other is "a preparation, run everywhere" to bring the concept of Web applications, To achieve a "one-prepared everywhere realized." And more importantly, if followed some of the principles of good design, it can be said of separating and content to create high-quality, reusable, easy to maintain and modify the application. For example, if the document in HTML embedded Java code too much (script), will lead the developed application is extremely complex, difficult to read, it is not easy reuse, but also for future maintenance and modification will also cause difficulties. In fact, CSDN the JSP / Servlet forum, can often see some questions, the code is very long, can logic is not very clear, a large number of HTML and Java code mixed together. This is the random development of the defects. Early dynamic pages mainly CGI (Common Gateway Interface, public Gateway Interface) technology, you can use different languages of the CGI programs, such as VB, C / C + + or Delphi, and so on. Though the technology of CGI is developed and powerful, because of difficulties in programming, and low efficiency, modify complex shortcomings, it is gradually being replaced by the trend. Of all the new technology, JSP / Servlet with more efficient and easy to program, more powerful, more secure and has a good portability, they have been many people believe that the future is the most dynamic site of the future development of technology. Similar to CGI, Servlet support request / response model. When a customer submit a request to the server, the server presented the request Servlet, Servlet responsible for handling requests and generate a response, and then gave the server, and then from the server sent to

计算机专业外文翻译

专业外文翻译 题目JSP Technology Conspectus and Specialties 系(院)计算机系 专业计算机科学与技术 班级 学生姓名 学号 指导教师 职称讲师 二〇一三年五月十六日

JSP Technology Conspectus and Specialties The JSP (Java Server Pages) technology is used by the Sun micro-system issued by the company to develop dynamic Web application technology. With its easy, cross-platform, in many dynamic Web application programming languages, in a short span of a few years, has formed a complete set of standards, and widely used in electronic commerce, etc. In China, the JSP now also got more extensive attention; get a good development, more and more dynamic website to JSP technology. The related technologies of JSP are briefly introduced. The JSP a simple technology can quickly and with the method of generating Web pages. Use the JSP technology Web page can be easily display dynamic content. The JSP technology are designed to make the construction based on Web applications easier and efficient, and these applications and various Web server, application server, the browser and development tools work together. The JSP technology isn't the only dynamic web technology, also not the first one, in the JSP technology existed before the emergence of several excellent dynamic web technologies, such as CGI, ASP, etc. With the introduction of these technologies under dynamic web technology, the development and the JSP. Technical JSP the development background and development history In web brief history, from a world wide web that most of the network information static on stock transactions evolution to acquisition of an operation and infrastructure. In a variety of applications, may be used for based on Web client, look no restrictions. Based on the browser client applications than traditional based on client/server applications has several advantages. These benefits include almost no limit client access and extremely simplified application deployment and management (to update an application, management personnel only need to change the program on a server, not thousands of installation in client applications). So, the software industry is rapidly to build on the client browser multilayer application. The rapid growth of exquisite based Web application requirements development of

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