单选题软件工程的结构化生命周期方法是将软件开发的全过程划分为相互独立而又相互依存的阶段,软件的逻辑模型是形成于 (52) ,数据流图描述数据在软件中流动和被处理变换的过程,它是以图示的方法来表示 (53) ,数据字典是软件需求分析阶段的最重要的工具之一,其最基本的功能是, (54) ,软件测试方法中,黑盒测试法和白盒测试法是常用的方法,其中黑盒测试法主要是用于测试 (55) 。
单选题The purpose of (66) is to enlarge the (67) , the set of addresses a program can utilize. For example, it might contain twice as many addresses as main memory. A program using all of it, therefore, would not be able to fit in main memory all at once. Nevertheless, the computer could execute such a program by Copying into main memory those portions of the program needed at any given point during execution.To facilitate copying (66) into real memory, the operating system divides it into pages, each of which contains a fixed number of addresses. Each page is stored on a disk until ii is needed. When the page is needed, the operating system copies it from disk to main memory, translating the (68) into real addresses. The process of translating virtual addresses into real addresses is called (69) . The copying of virtual pages from disk to main memory is known as (70) or swapping.
单选题分布式数据库用户无需知道数据的物理位置,称为 (60) 。 A.分片透明 B.复制透明 C.位置透明 D.逻辑透明
单选题甲经销商擅自复制并销售乙公司开发的OA软件光盘已构成侵权。丙企业在未知的情形下从甲经销商处购入10张并已安装使用。在丙企业知道了所使用的软件为侵权复制品的情形下,以下说法正确的是______。
单选题RS-232C的机械特性规定使用的连接器类型为______。
单选题在文件管理系统中,位示图(Bitmap)可用来记录磁盘存储器的使用情况。假如计算机系统的字长为32位,磁盘存储器上的物理块依次编号为0,1,2……那么3552号物理块在位示图中的第______个字。 A.111 B.112 C.223 D.224
单选题设有关系R(S,D,M),其函数依赖集F=S→D,D→M。则关系R至多满足 (56) 。
单选题______简称CRC,在计算机网络中用得最广泛。其编码过程使用______运算。假设采用的生成多项式是G(X)=X
4
+X
3
+X+1,给定为11001010101,则编码后的报文为______。
单选题The ARPANET (66) ( the rules of syntax that enable computers to communicate on a network) were originally designed for openness and flexibility, not for (67) The ARPA researchers needed to share information easily, so everyone needed to be an unrestricted "insider" on the network. Although the approach was appropriate at the time, it is not one that lends itself to today's commercial and government use. As more locations with computers (known as (68) in Internet parlance)joined the ARPANET, the usefulness of the network grew. The ARPANET consisted primarily of university and government computers, and the applications supported on this network were simple: electronic mail ( E - mail), electronic news groups, and (69) connection to other computers. By 1971, the Internet linked about two dozen research and government sites, and researchers had begun to use it to exchange (70) not directly related to the ARPANET itself. The network was becoming an important tool for collaborative research.
单选题有如下关系R、S、T、U,则关系代数表达式(R*T-S)÷U为(56)。
单选题B/S体系结构中属于客户端的是 (64) 。 A.浏览器 B.Web服务器 C.应用服务器 D.数据库服务器
单选题如果希望别的计算机不能通过ping命令测试服务器的连通情况,可以(7)。如果希望通过默认的Telnet端口连接服务器,则下面对防火墙配置正确的是(8)。
单选题在操作系统中引入并发可以提高系统效率。若有两个程序A和B,A程序执行时所做的工作按次序需要用CPU:10秒,DEV1:5秒;CPU:5秒;DEV2:10秒;CPU:l0秒。B程序执行时所作的工作按次序需要用DEV1:10秒;CPU:10秒;DEV2:5秒;CPU:5秒;DEV2:10秒,则:如果有顺序环境下执行A、B两个程序,CPU的利用率为 (9) 。
单选题以下关于触发器的说法不正确的是______
单选题防火墙的安全性包括 (23) 。 ①用户认证 ②域名服务 ③邮件处理 ④IP层的安全性 ⑤防火墙的IP安全性
单选题软件维护是一项非常复杂和困难的工作,以下哪个不属于其表现 (42) 。
单选题在计算机的浮点数表示中,主要影响数值表示范围的是______。
单选题火车售票点T1、T2 分别售出了两张2007 年10 月20 日到北京的硬卧票,但数据库里的剩余票数却只减了两张,造成数据的不一致,原因是 (46) 。
单选题对于给定的关键字序列{47, 34, 13, 12, 52, 38, 33, 27, 5},若用链地址法(拉 链法)解决冲突来构造哈希表,且哈希函数为H(key)=key%ll,则( )
