计算机英语学习.docx

计算机英语翻译100010001=i=1na2+b237英语学习网第一章1By using various coding techniques, groups of bits can be made to represent not only binary numbers but also other discrete symbols, such as decimal digits or letters of the alphabet.应用多种编码技术，一组二进制数字不但可以表示二进制数据，而且还可以表示其它的离散符号，如十进制数字或字母表中的字母。2System software includes not only the complex programs used by technicians to create application software in the first place but also the organizational programs needed to start up the computer and govern its use of other programs.系统软件不仅包括技术人员用于创建应用软件的复杂程序，而且还包括用于启动计算机和提供给其他程序使用的管理程序。3Data are numbers and other binary-code information that are operated on to achieve required computational results.数据是数字和其他的二进制代码信息，通过处理这些数据得到所需要的计算结果。4Rather than arithmetically or logically manipulating characters, a computer may concatenate strings of characters, replace some characters with others, or otherwise manipulate character strings.计算机能将若干字符连成串，用一些字符代替其他字符或另行处理字符串，而不是用算术方法或逻辑方法处理字符。5Software applications like word processing, electronic spreadsheets, database management programs, painting and drawing programs, desktop publishing, and so forth became commercially available, giving more people reasons to use a computer.软件应用，像文字处理、电子表格、数据库管理程序、绘图程序及桌面印刷等进入商业市场，使更多的人去使用计算机。第二章1 By asserting these internal and external control signals in the proper sequence, the control unit causes the CPU and the rest of the computer to perform the operation needed to correctly process instructions.通过维护内部和外部控制信号的正确顺序，控制单元促使CPU和计算机的其他部件根据正确的处理指令完成操作。2 In a computer with virtual memory, less-used parts of programs are shifted from RAM to a hard disk and are moved back only when needed.在使用了虚拟存储器的计算机中，很少使用的程序被从RAM移到硬盘中，仅当需要时才被移回来。3 A technique used to compensate for the mismatch in operating speeds is to employ an extremely fast, small cache between the CPU and main memory whose access time is close to processor logic clock cycle time.用于弥补操作速度的不匹配的一项技术是在CPU和内存之间采用非常快的小容量高速缓冲存储器，它的存取时间接近于处理器的逻辑时钟周期。4 The data transfer rate of peripherals is usually slower than the transfer rate of the CPU, and consequently, a synchronization mechanism may be needed.外部设备的数据传输速率通常比CPU的数据传输率更慢，相应的，需要一种同步机制。5 In some computers the interrupt vector is an address that points to a location in memory where the beginning address of the I/O service routine is stored.在一些计算机中，中断向量是一个地址，它指向存储器中存储I/O 服务程序其实地址的单元。第三章1The purpose of parallel processing is to speed up the computer processing capability and increase its throughout, that is, the amount of processing that can be accomplished during a given interval of time.并行处理的目的是加快计算机的处理速度并增加其吞吐量，所谓吞吐量是在制定规定的时间间隔内所完成的指令。2 It is characteristic of pipelines that several computations can be in process in distinct segments at the same time.流水线的特征就在于在同一时间里可以在不同的子过程中处理几个不同的运算。3. To achieve the required level of high performance it is necessary to utilize the fastest and most reliable hardware and apply innovative procedures from vector and parallel processing techniques.为了获得所需要的高性能，有必要采用最快和最可靠的硬件并应用向量处理与并行处理等新技术的革新过程。4. In general, the greater the number of instructions set, the larger the propagation delay is within the CPU.总的来说，指令集中的指令数越多，CPU中的传播延迟越大。5. Although CISC processors are more complex, this complexity does not necessarily increase development costs尽管CISC处理器更为复杂，但这并不一定导致开发成本的增加。第四章1. Primitives In short, Communication problems arise when the language used for an algorithms representation is not precisely defined or when information is not given in adequate detail.原语 简而言之，算法描述所采用的语言不具有精确的定义或者信息不够详细也会使交流产生问题。2. Another common algorithmic structure involves that the need to continue executing a statement or sequence of statements as long as some condition remains true.另一种常见的算法结构是当条件为“真”时，循环执行一条语句或者语句序列。3. In many algorithms, running time will vary not only for inputs of different sizes, but also for different inputs of the same size.在众多算法中，影响运行时间的不仅有不同长度的输入，也包括相同长度的不同输入。4. Thus, dynamic programming is bottom-up technique that usually begins by solving the smallest subproblems ,saving these results, and then reusing them to solve larger and larger subproblems until the solution to the original problems obtained.因此，动态程序设计是一种从下而上的方法，这种方法通常先解决最小的子问题，并保存其解，再利用这些解对较大问题求解，一步一步地进行直至得到原问题的解。5. The conversion from this conceptual one-dimensional array organization to the actual arrangement within the machines memory is straightforward, and the data can be stored in a sequence of 24 memory cells with consecutive addresses in the same order envisioned by the programmer.从这种概念性的一维的 方式到机器内存中的实际安排的转换是非常直接的。这些数据可以保存在由程序员想象的相同顺序的24个相邻的内存单元中。第五章1. Documentation is needed for everyone who will be involved with the program-users, operators, and programmers.与程序设计相关的每一个人-用户、操作员和程序员都需要文档。2. Rather, programs written in a high-level language or assembly language are converted to machine language, which is then executed by the computer.而是，用高级语言或者汇编语言编写的程序被转换成机器语言，然后由计算机执行。3. The corresponding programs set forth precise procedures, or series of instructions, and the programmer has to follow a proper order of actions to solve a problem.相应的程序建立了精确的过程，或者执行序列，并且程序员必须按照正确的执行序列来解决问题。4.4GLs may not entirely replace third-generation languages because they are usually focused on specific tasks and hence offer fewer options.4Gls可能并不能完全替换掉第三代语言是因为她们通常集中解决专门的任务并因此可供的选择很少.5. Inheritance is the means by which objects of a class can access member variables and functions contained in previously defined class, without having to restate those definitions.继承是一种方法，通过它，类的对象可以访问以前精确定义过的类中的成员变量和函数，而不用重新声明那些定义.第六章1. The majority of an installations utility software consists of programs for performing activities that are fundamental to computer installations yet not included in the operating system.安装实用软件大都包括用于执行动作的程序，这些动作对于计算机的安装非常重要但是没有包括在操作系统之中2. Modern shells perform this task by means of a graphical user interface (GUI) in which objects to be manipulated, such as files and programs, are represented pictorially on the monitor screen as icons.现代的外壳程序是通过图形用户界面（GUI）来完成这一工作的，在图形界面中要操作的诸如文件和程序等对象是在计算机屏幕上以图形化的图标方式表示的。3. The basic technique for a time-sharing system is to have multiple users simultaneously using the system through terminals, with the operating system interleaving the execution of each user program in a short burst ,or quantum, of computation. 分时系统的基本技术是要有多个用户通过终端同时使用这一系统，操作系统在一个短暂的时间片内定时交替执行每一个用户程序4. A real-time process or task is one that is executed in connection with some process or function or set of events external to the computer system and that must meet one or more deadlines to interact effectively and correctly with the external environment.实时的进程或任务是指那种运行时要与一些处理或函数或者计算机系统以外的一系列事件相联系，并且它必须满足一个或多个时间界限来与外部环境有效地和正确地交互的进程或任务5. Providing a similar interface to Windows 9x, it is a multitasking , multiprocessing operating system with built-in support for large networks of computersthat is, Windows NT is a multi-user system.它提供了与Windows 9x类似的用户界面，是一个多任务、多进程的操作系统，它在系统内提供了对大型计算机网络的支持-这就是说，Windows NT是一个多用户系统。第七章1. Application software is the software designed to help you solve problems specific to business or perform specific business task.应用软件是设计用来帮助你们解决专用于商业或执行专门商业任务的软件。2Although applications software packages differ in their use of specific commands and functions, most of them have some features in common.虽然应用软件包在特定命令和功能的使用上不同，绝大多数应用软件有一些共同的特征。3Many applications software programs allow you to copy an item from one document and then paste it into another document or application, or copy an item and place the copy in another part of the same document.许多应用软件程序允许你从一个文件中复制一项然后粘贴到另一个文件或应用程序中，或者复制一项然后把它放置在同一文档的另一个位置。4. The user can do all these manipulations on screen, in“ wysiwyg” fashion, before printing out hardcopy.用户在打印之前可以在屏幕上以所见即所得的方式完成这些操作。5. Its worth nothing that word processing programs(and indeed most forms of applications software) come from the manufacturer with default settings.值得一提的是来自于生产商的文字处理程序（实际上绝大多数的应用程序）具有默认设置。第八章1. Since the files and application programs are created by different programmers over a long period, the various files are likely to have different formats and the programs may be written in several programming languages.由于文件和程序是由不同的程序员创建的，因此不同的文件可能采用不同的格式，不同的程序也可能是采用不同的计算机语言来编写。2. In what follows, we shall see the concepts and algorithms that have been developed for database systems to solve the problems mentioned.接下来看一看数据库系统为了解决上述问题而提出的概念和算法。3. Despite the use of simpler structures at the logical level, some complexity remains, because of the large size of the database.尽管在逻辑层使用了比较简单的结构，但由于数据库的规模巨大，所以仍存在一定程度的复杂性。4. Returning to the customer-record type definition, note that, in declaring the type customer, we have not declared any variables.在回过头来看一下customer记录类型的定义，注意，我们只是定义了customer类型而没有定义任何变量。5. Ensuring the atomicity and durability properties is the responsibility of the database system itself-specifically,of the transaction-management component.确保原子性和持久性的属性是数据库本身的任务，更确切一些， 是事务管理部件的任务。第九章1. Just as manufactures look for ways to assure the quality of the products they produced, so too must software engineers find methods to assure that their products are of acceptable quality and utility.正如生产商寻求方法以保证他们所生产的产品的质量一样，软件工程师也必须设法保证他们的产品在质量上和效用上是可接受的。2. An abstraction is a description of the problem at some level of generalization that allows us to concentrate on the key aspects of the problem without getting mired in the details。抽象是问题在某些概括层次上的描述，它使得我们将注意力集中于问题的关键方面而不至于陷于细节的泥潭之中。3. The importance of these approaches is their capture of our design experience, enabling us to capitalize on our past projects by reusing both what we have done and what we have learned by doing it.这些方法的重要性在于它们集中了我们的设计经验，使我们能够通过复用已有的成果和通过完成那个项目所学到的知识充分地利用过去开发的项目。4. Upon completion of acceptance testing, the accepted system is installed in the environment in which it will be used; a final installation test is run to make sure that the system still functions as it should.验收测试完成之后，验收过的系统就要被安装在实际的运行环境中，通过安装测试来确保系统仍然按照期望的那样正常运行。5. Software development is both a creative and a step-by-step process, often involving many people producing many different kinds of products.软件开发既是一个创造性的过程又是一个按部就班的过程，经常涉及到多个不同的人生产不同类型的产品。第十章1Encapsulation is then the technique for packaging the information in such a way as to hide what should be hidden, and make visible what is intended to be visible.封装是一种将应该隐藏的信息隐藏起来，将应该可见的信息是可见的方式的包装技术。2This across-the process consistency is a key difference between more traditional procedural development and the OO development process.这种贯穿于开发过程的一致性是传统的过程式开发与OO开发过程的根本区别。3Domain knowledge enables the developers to understand the context in which the system will be used and to describe the requirements in a way that the user will understand them.领域知识使开发人员以系统所使用的方式理解系统的使用环境，并且以用户将要理解方式描述需求。4. The system design is considered to be a high-level abstraction of what will eventually be the program design.系统设计被认为是最终成为程序设计的高级抽象。5. It is usually necessary for the implementers to refine the hierarchical structures and make adjustments as the requirements grow and mature.实施者通常有必要对层次结构加以精炼，并且随着需求的变化和成雪进行适当的调整。第十一章1. Organizations with hundreds of offices spread over a wide geographical area routinely expect to be able to examine the current status of even their most remote outpost at the push of a button.拥有数百个办公室的组织向更广的区域扩展，并且期望只需按一下某一个按钮，就能够了解位于遥远地区的机构当前运作的情况。2. The old model of a single computer serving all of the organizations computational needs has been replaced by one in which a large number of separate but interconnected computers do the job.单台计算机为机构中所有的计算机需求服务这一概念很快被大量分散但又互联的计算机来共同完成的模式所代替。3 .Technological advances are making it possible for communications links to carry more and faster signals. As a result, services are evolving to allow use of the expanded capacity, including extensions to established telephone service.技术的进步 建立可以传输更多更快信号的通信链路成为可能，从而提供了对这些扩展的通信能力的使用的新业务也出现了。4. There is no generally accepted taxonomy into which all computer networks fit, but two dimensions stand out as important: transmission technology and scale.不存在被普遍接受的所有计算机网络都是用的分类法，但是有两个标准很重要：传输技术和规模。5. ISOs purpose is to promote the development of standardization and related activities to facilitate international exchange of goods and services.ISO的目标是推动标准化及其相关活动的发展，以促进国际间的贸易和服务往来。第十三章 1. The ARPAnet was designed so that even if part of its physical structure were destroyed, information could still be sent to any remaining destination. 设计ARPAnet的目的是，即使网络中的某一具体部分遭到破坏，信息仍能传递到任一个残存的目标点。2. To map a name onto an IP address, an application program calls a library procedure called the resolver, passing it the name as a parameter.为了把一个名字映射为一个IP地址，应用程序调用一种名叫解析器的库程序，将名字作为参数进行传递。3. Within the Internet, e-mail is delivered by having the source machine establish a TCP connection to port 25 of the destination machine.在因特网中，通过在源机器和目的机器的第25号端口之间建立TCP连接来传递电子邮件4. An intranet uses network technologies as a tool to facilitate communication between people or workgroups to improve the data sharing capability and overall knowledge base of an organizations employees.企业内部网把网络技术当作一个工具利用人们或者工作组间的通信来提高企业雇员的数据共享能力和总体知识库。5. An organizations intranet typically includes Internet access but is firewalled so that its computers cannot be reached directly from the outside.一个组织机构的企业内部网典型地包括Internet接入但还有防火墙以从使外部不能直接访问到其计算机。C/C+中Const用法总结const类型定义：指明变量或对象的值是不能被更新,引入目的是为了取代预编译指令 *常量必须被初始化* cons的作用 （1）可以定义const常量 例如： const int Max=100; int ArrayMax; （2）便于进行类型检查 例如： void f(const int i) . 编译器就会知道i是一个常量，不允许修改； （3）可以保护被修饰的东西，防止意外的修改，增强程序的健壮性。 还是上面的例子，如果在函数体内修改了