计算机专业英语论文

1、专业英语课程作业 学生姓名 学 号 院 系 专 业 任课教师 二一五年六月一、英译中（英文科技资料翻译）原文：An operating system is the software which acts as an interface between a user of a computer and the computer hardware.The purpose of an operating system is to provide an environment in which a user may execute program. The primary goal of an ope

2、rating system is thus to make the computer system convenient to use. A secondary goal is to use the computer hardware in an efficient way. We can view an operating system as a resource allocator. A computer system has many resources which may be required to solve a problem: CPU time, memory space, ,

3、 input/output(I/O) devices, and so on.The operating system acts as the manager of these resources and allocates them to specific programs and users as necessary for their tasks. Since there may be many, possibly conflicting, requests for resources, the o/s must decide which requests are allocated re

4、sources to operate the computer system fairly and efficiently. Multimedia means, from the users perspective, that computer information can be represented through audio and/or video, in addition to text, image, graphics and animation . The integration of these media into the computer provides additio

5、nal possibilities for the use of computational power currently available (e.g., for interactive presentation of huge amounts of information ). Furthermore, these data can be transmitted though computer and telecommunication networks, which implies applications in the areas of information distributio

6、n and cooperative work.Multimedia provides the possibility for a spectrum of new applications, many of which are in place today.A multimedia system distinguishes itself from other systems through several properties. We elaborate on the most important properties such as combination of the media, medi

7、a-independence, computer control and integration.Not every arbitrary combination of media justifies the usage of the term multimedia. A simple text processing program with incorporated images is often called a multimedia application because two media are processed through one program.But one should

8、talk about multimedia only when both continuous and discrete media are utilized.A text processing program with incorporated images is therefore not a multimedia application. An important aspect of different media is their level of independence from each other. In general, there is a request for inde

9、pendence of different media, but multimedia may require several levels of independence. On the one hand, a computer-controlled video recorder stores audio and video information, but there is an inherently tight connection between the two types of media. Both media are coupled together through the co

10、mmon storage medium of the tape. On the other hand, for the purpose of presentations, the combination of DAT recorder (Digital Audio Tape) signals and computer-available text satisfies the request for media-independence.Early computers were(physically) very large machines run from a console.The prog

11、rammer would write a program and then operate the program directly from the operators console. Software such as assemblers, loaders, and compilers improved on the convenience of programming the system, but also required substantial set-up time. To reduce the setup time, operators were hired and simi

12、lar jobs were batched together.Batch systems allowed automatic job sequencing by a resident monitor and improved the overall utilization of the computer greatly.The computer no longer had to wait for human operation. CPU utilization was still low, however, because of the slow speed of the I/O device

13、s relative to the CPU. Offline operation of slow devices was tried.Buffering was another approach to improving system performance by overlapping the input, output, and computation of a single job. Finally, spooling allowed the CPU to overlap the input of one job with the computation and output of ot

14、her jobs.Spooling also provides a pool of jobs which have been read and are waiting to be run. This job pool supports the concept of multiprogramming. With multiprogramming, several jobs are kept in memory at one time; the CPU is switched back and forth between them in order to increase CPU utilizat

15、ion and to decrease the total real time needed to execute a job. Multiprogramming, which was developed to improve performance, also allows time sharing. Time-shared operating systems allow many users (from one to several hundred) to use a computer system interactive at the same time. As the system s

16、witches rapidly from one user to the next, each user is given the impression that he has his own computer. Other operating systems types include real-time systems and multiprocessor systems. A real-time system is often used as control device in a dedicated application. Sensors bring data to the comp

17、uter. The computer must analyze the data and possibly adjust controls to modify the sensor inputs. Systems, which control scientific experiments, medical computer systems, industrial control systems, and some display systems are real-time systems. A real-time operating system has well-defined fixed

18、time constraintsProcessing must be done within the defined constraints, or the system will fail. A multiprocessor system has more than one CPU. The obvious advantages would appear to be greater computing power and reliability. There are various types of operating systems for multiprocessors and mult

19、icomputers. It is more or less possible to distinguish two kinds of operating systems for multiple CPU systems: Loosely coupled, such as network operating system and distributed o/s, and tightly coupled, such as parallel o/s. As we shall see, loosely and tightly-coupled s/w is rought analogous to lo

20、osely and tight-coupled h/w. The operating system must ensure correct operation of the computer system. To prevent user programs from interfering with the proper operation of the system, the h/w was modified to create two modes: user mode and monitor mode. Various instructions(such as I/O instructio

21、ns and halt instructions) are privileged and can only be executed in monitor mode. The memory in which the monitor resides must also be protected from modification by the user. A time prevents infinite loops. Once these changes (dual mode, privileged instructions, memory protection, timer interrupt)

22、 have been made to the basic computer architecture, it is possible to write a correct operating system. 译文：操作系统是作为计算机用户和计算机硬件之间接口的软件。操作系统的目的是提供给用户可以执行程序的环境。因此，操作系统的主要目标是使计算机系统便于使用。其次的目标是给计算机硬件提供高效的使用路径。我们可以把操作系统看作是一个资源分配器。一个计算机系统拥有许多资源，因此需要去解决问题，例如CPU时间，内存空间，文件的存储，输入输出的设备等。操作系统就像是这些资源的管理员，在需要的时候，它会把

23、资源分配给特定的程序和用户。因此，会有很多有可能产生冲突的资源请求，操作系统必须决定分配资源给哪个请求，使得计算机系统合理有效的运行。从用户的观点，多媒体技术意味着，计算机信息不仅可以通过文本、图象、图形和动画，还可以通过音频或者视频表现出来。多媒体与计算机的综合为计算机的普遍应用提供了额外的可行性（例如：大量信息的交互式表现）。此外，这些数据可虽然计算机和电信网络中，这意味着应用程序在信息分发和协同工作的区域中传输。多媒体技术为一连串的新应用程序提供了可能性（多媒体技术是一连串的新应用程序成为可能），并且许多已经开发到位。一个多媒体系统通过数个属性使自己有别于其他系统。我们对最重要的一些属性

24、进行详细解释，如媒体的组合，媒体的独立性，计算机控制和集成。并不是任意的媒体组合都能满足术语“多媒体”的要求。一个支持图像处理的简单文本处理程序通常被称为一个多媒体应用程序，这是因为两种媒体通过一个程序被处理。但是我们说到的“多媒体“应该是使用了连续媒体和离散媒体。一个支持图像处理的简单文本处理程序因此并不是一个多媒体应用程序。 媒体的一个重要性质是他们之间的独立性。一般说来，对于不同媒体间需要一个关于独立性的要求，但是多媒体可能需要几个等级的独立性。一方面，一个计算机控制的录像机存储音频和视频信息，但是在这两种类型的媒体间存在一个内在的紧密联系。那就是，这两种媒体通过共同的磁带存储媒介联接在

25、一起。另一方面，出于表达的目的，数字录音带信号和有效的计算机文本组合满足媒体独立性的需求。早期的计算机是从控制台运行的体积非常大的机器。程序员要写一条程序然后直接从操作者的控制台操作程序。像汇编程序、装入程序及编译程序这样的软件使系统软件编程更加方便，但是同时也需要大量的启动时间。为了减少这些启动时间，操作者被雇佣，同时相似的工作被成批的处理。批处理系统通过一个常驻内存的监控程序允许自动的作业定序。批处理系统由常驻监视和改进计算机自动允许测序工作.因此计算机不再需要等待人工操作。 然而，CPU使用率仍然低，这是因为I/O设备的处理速度比CPU的处理速度慢。慢速设备的脱机操作已经尝试。缓冲是以通

26、过重叠的输入，输出，和计算单个作业的改善系统性能的另一种方法。最后，假脱机允许在CPU和其他作业的计算和输出重叠作业的输入。伪脱机也为那些已经被读入并且还在等待运行的作业提供一个作业池。这个作业池支持一种叫做多程序设计的概念。在这种多程序设计技术中，多个作业可以同时存放在内存中。CPU在这些作业中来回切换控制，以增加CPU使用率，同时减少执行一条作业的总时间。多道程序设计被开发来提高性能，也允许分时。分时操作系统允许多个用户（从一个到几百个）同时交互式地使用计算机系统。由于系统迅速地从一个用户切换到下一个用户，每一个用户被给予一种他拥有自己的计算机的印象。其他操作系统类型包括实时系统和多处理机

27、系统。实时系统通常被用作专用的应用的控制设备。传感器把数据带给计算机。计算机必须分析数据，也可能调整控制去修改传感器的输入。控制科学的实验，医学的计算机系统，工业的控制系统和一些显示系统等系统都是实时系统。实时操作系统有定义明确的固定的时间约束。处理必须在定义的约束中完成，否则系统将失败。多处理机系统有不只一个CPU。显著的优势好像是强大的计算能力和可靠性。有各种各样的操作系统用于多处理机和多计算机。这或多或少可能区分两种多CPU系统的操作系统：松耦合，例如网络操作系统和分布式操作系统，和紧耦合，如并行操作系统。我们应该看到，松紧耦合软件大概类似于松紧耦合硬件。操作系统必须确保改正计算机系统的操作。为了阻止用户程序干扰系统适当的操作，硬件被修改成两种模式：用户模式和监控模式。许多指令（例如I/O指令和中断指令）是有特权的，只能在监控模式下被执行。监控程序所在的内存也必须保护起来以防用户修改。定时器可以防止死循环。一旦这些对基本计算机体系结构的改变（双模，权限指令，内存保护，定时器中断）被做到，这可能写成一个改进的操作系统。二、中译英（将中文科技资料翻译成英文）原文：GPS接收器使用它接收的消息来确定每个消息的传输时间和计算到各个卫星的距离。这些距离连同诸卫星的位置被用来计算接收器的位置。然后显示这个位置，或许连同移动