計算機專業(yè)英語論文

1、專業(yè)英語課程作業(yè) 學生姓名 學 號 院 系 專 業(yè) 任課教師 二一五年六月一、英譯中（英文科技資料翻譯）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. 譯文：操作系統(tǒng)是作為計算機用戶和計算機硬件之間接口的軟件。操作系統(tǒng)的目的是提供給用戶可以執(zhí)行程序的環(huán)境。因此，操作系統(tǒng)的主要目標是使計算機系統(tǒng)便于使用。其次的目標是給計算機硬件提供高效的使用路徑。我們可以把操作系統(tǒng)看作是一個資源分配器。一個計算機系統(tǒng)擁有許多資源，因此需要去解決問題，例如CPU時間，內存空間，文件的存儲，輸入輸出的設備等。操作系統(tǒng)就像是這些資源的管理員，在需要的時候，它會把

23、資源分配給特定的程序和用戶。因此，會有很多有可能產生沖突的資源請求，操作系統(tǒng)必須決定分配資源給哪個請求，使得計算機系統(tǒng)合理有效的運行。從用戶的觀點，多媒體技術意味著，計算機信息不僅可以通過文本、圖象、圖形和動畫，還可以通過音頻或者視頻表現(xiàn)出來。多媒體與計算機的綜合為計算機的普遍應用提供了額外的可行性（例如：大量信息的交互式表現(xiàn)）。此外，這些數(shù)據(jù)可雖然計算機和電信網(wǎng)絡中，這意味著應用程序在信息分發(fā)和協(xié)同工作的區(qū)域中傳輸。多媒體技術為一連串的新應用程序提供了可能性（多媒體技術是一連串的新應用程序成為可能），并且許多已經(jīng)開發(fā)到位。一個多媒體系統(tǒng)通過數(shù)個屬性使自己有別于其他系統(tǒng)。我們對最重要的一些屬性

24、進行詳細解釋，如媒體的組合，媒體的獨立性，計算機控制和集成。并不是任意的媒體組合都能滿足術語“多媒體”的要求。一個支持圖像處理的簡單文本處理程序通常被稱為一個多媒體應用程序，這是因為兩種媒體通過一個程序被處理。但是我們說到的“多媒體“應該是使用了連續(xù)媒體和離散媒體。一個支持圖像處理的簡單文本處理程序因此并不是一個多媒體應用程序。 媒體的一個重要性質是他們之間的獨立性。一般說來，對于不同媒體間需要一個關于獨立性的要求，但是多媒體可能需要幾個等級的獨立性。一方面，一個計算機控制的錄像機存儲音頻和視頻信息，但是在這兩種類型的媒體間存在一個內在的緊密聯(lián)系。那就是，這兩種媒體通過共同的磁帶存儲媒介聯(lián)接在

25、一起。另一方面，出于表達的目的，數(shù)字錄音帶信號和有效的計算機文本組合滿足媒體獨立性的需求。早期的計算機是從控制臺運行的體積非常大的機器。程序員要寫一條程序然后直接從操作者的控制臺操作程序。像匯編程序、裝入程序及編譯程序這樣的軟件使系統(tǒng)軟件編程更加方便，但是同時也需要大量的啟動時間。為了減少這些啟動時間，操作者被雇傭，同時相似的工作被成批的處理。批處理系統(tǒng)通過一個常駐內存的監(jiān)控程序允許自動的作業(yè)定序。批處理系統(tǒng)由常駐監(jiān)視和改進計算機自動允許測序工作.因此計算機不再需要等待人工操作。 然而，CPU使用率仍然低，這是因為I/O設備的處理速度比CPU的處理速度慢。慢速設備的脫機操作已經(jīng)嘗試。緩沖是以通

26、過重疊的輸入，輸出，和計算單個作業(yè)的改善系統(tǒng)性能的另一種方法。最后，假脫機允許在CPU和其他作業(yè)的計算和輸出重疊作業(yè)的輸入。偽脫機也為那些已經(jīng)被讀入并且還在等待運行的作業(yè)提供一個作業(yè)池。這個作業(yè)池支持一種叫做多程序設計的概念。在這種多程序設計技術中，多個作業(yè)可以同時存放在內存中。CPU在這些作業(yè)中來回切換控制，以增加CPU使用率，同時減少執(zhí)行一條作業(yè)的總時間。多道程序設計被開發(fā)來提高性能，也允許分時。分時操作系統(tǒng)允許多個用戶（從一個到幾百個）同時交互式地使用計算機系統(tǒng)。由于系統(tǒng)迅速地從一個用戶切換到下一個用戶，每一個用戶被給予一種他擁有自己的計算機的印象。其他操作系統(tǒng)類型包括實時系統(tǒng)和多處理機

27、系統(tǒng)。實時系統(tǒng)通常被用作專用的應用的控制設備。傳感器把數(shù)據(jù)帶給計算機。計算機必須分析數(shù)據(jù)，也可能調整控制去修改傳感器的輸入?？刂瓶茖W的實驗，醫(yī)學的計算機系統(tǒng)，工業(yè)的控制系統(tǒng)和一些顯示系統(tǒng)等系統(tǒng)都是實時系統(tǒng)。實時操作系統(tǒng)有定義明確的固定的時間約束。處理必須在定義的約束中完成，否則系統(tǒng)將失敗。多處理機系統(tǒng)有不只一個CPU。顯著的優(yōu)勢好像是強大的計算能力和可靠性。有各種各樣的操作系統(tǒng)用于多處理機和多計算機。這或多或少可能區(qū)分兩種多CPU系統(tǒng)的操作系統(tǒng)：松耦合，例如網(wǎng)絡操作系統(tǒng)和分布式操作系統(tǒng)，和緊耦合，如并行操作系統(tǒng)。我們應該看到，松緊耦合軟件大概類似于松緊耦合硬件。操作系統(tǒng)必須確保改正計算機系統(tǒng)的操作。為了阻止用戶程序干擾系統(tǒng)適當?shù)牟僮鳎布恍薷某蓛煞N模式：用戶模式和監(jiān)控模式。許多指令（例如I/O指令和中斷指令）是有特權的，只能在監(jiān)控模式下被執(zhí)行。監(jiān)控程序所在的內存也必須保護起來以防用戶修改。定時器可以防止死循環(huán)。一旦這些對基本計算機體系結構的改變（雙模，權限指令，內存保護，定時器中斷）被做到，這可能寫成一個改進的操作系統(tǒng)。二、中譯英（將中文科技資料翻譯成英文）原文：GPS接收器使用它接收的消息來確定每個消息的傳輸時間和計算到各個衛(wèi)星的距離。這些距離連同諸衛(wèi)星的位置被用來計算接收器的位置。然后顯示這個位置，或許連同移動