单选题《中华人民共和国计算机信息网络国际联网管理暂行规定》规定：从事国际联网经营活动的和从事非经营活动的接入单位必须具备下列条件： (54) 。 (1) 是依法设立的企业法人或者事业法人 (2) 具有相应的计算机信息网络、装备以及相应的技术人员和管理人员 (3) 具有健全的安全保密管理制度和技术保护措施 (4) 符合法律和国务院规定的其他条件

单选题 当某程序执行时，利用重定位存储管理方式来访问内存，是将{{U}} {{U}} 22 {{/U}} {{/U}}相加得到{{U}} {{U}} 23 {{/U}} {{/U}}来进行访问的。

单选题 (49) 的发展在80年代末至90年代中出现了一个高潮，UML就是其产物。

单选题某系统中有四种互斥资源R1、R2、R3 和R4，可用资源数分别为3、5、6 和8。假设在T0 时刻有P1、P2、P3 和P4 四个进程，并且这些进程对资源的最大需求量和已分配资源数如下表所示，那么在T0 时刻系统中R1、R2、R3 和R4 的剩余资源数分别为（22） 。如果从T0 时刻开始进程按 （23） 顺序逐个调度执行，那么系统状态是安全的。

单选题One of the functions of the (71) is to store the applications programs or the various secondaries. The (72) may have similar or dissimilar functions. The same control code received from two different, secondaries may warrant two different actions on the part of the host computer. If the system so requires, the host computer must also provide (73) for the centralized data and the software for database management. Data information is normally stored in auxiliary memories to which the computer has ready access. The (74) peripherals connected to the host computer allow for human entry and intervention. As needs change, application programs may require additions, deletions, or changes. Data link problems also arise which are (75) the range of the computer's programmed capabilities. In such cases, human entry is required to make the necessary changes to resolve the existing problems.

单选题Typically, these are concern with the establishment of (66) the network and with the control of the flow of messages across this channel. The provision of such facilities is only part of the network requirements, however, since in many applications the communicating computers may be of different types. This means that they may use different programming languages and, more importantly, different forms of (67) interface between user(application)program, normally referred to, as application processes or APs, and the underlying communication services may be (68) For example, one computer may be a small single -user computer, while another may be a large (69) system. In the earlier days of computer communication, these issues meantthat only closed communities of computers ( that is, from the same manufacturer) could communicate with each other in a meaningful way. IBM’s Systems Network. Architecture (SNA) and DEC's Digital Network Architecture (DNA) are just two examples of Communication software packages produced by manufacturers to allow their systems to be int erconnected together. These proprietary packages, however, of which there am still many inexistence, do not address the problem of universal interconnect ability, or open systems interconnection. In an attempt to alleviate this problem, (70) , in the late 1970s, formulated a reference model to provide a common basis ( or the coordination of standards developments and to allow existing and evolving standards activities to beplaced into perspective with one another.

单选题把网络117.15.32.0/23划分为117.15.32.0/27，则得到的子网是______个。每个子网中可使用的主机地址是______个。

单选题以下IP地址中，属于私有专用IP地址的是______。

单选题 关系数据库用______来表示实体之间的联系，其任何检索操作的实现都是由______三种基本操作组合而成的。

单选题软件开发的螺旋模型综合了瀑布模型和演化模型的优点，并增加了______。采用螺旋模型时，软件开发沿着螺线自内向外旋转，每转一圈都要对______进行识别、分析，并采取相应的对策。螺旋线第一圈的开始点可能是一个______。从第二圈开始，一个新产品开发项目开始了，新产品的演化沿着螺旋线进行若干次迭代，一直运转剑软件生命期结束。

单选题为了解决高速CPU与内存之间的速度匹配问题，在CPU与内存之间增加了 (3) 。

单选题某一计算机系统连接有三台外设，其数据传输率分别为：20Mbps，30Mbps，60Mbps如果采用数组多路通道方式连接这三台外设，则通道的设计极限流量应不小于 (20) ；如果采用字节多路通道方式连接这三台外设，则通道的设计极限流量应不小于 (21) 。

单选题数据库镜像技术的优点是（ ）。

单选题关于ARP表，以下描述中正确的是 (67) 。

单选题在用多模光纤传输基带脉冲信号时，光缆越长，偏差 (16) ，波形失真 (16) 。

单选题下列有关存储器的读写速度，正确的排序是 (4) 。 A) 硬盘＜光盘＜随机存取存储器Ram＜Cache B) 硬盘＜光盘＜Cache＜随机存取存储器Ram C) 光盘＜硬盘＜随机存取存储器Ram＜Cache D) 光盘＜硬盘＜Cache＜随机存取存储器Ram

单选题若给定的关系模式为良，U={A，B，C），F={AB→C，C→B），则关系R（ ）。

单选题下列指令中有几条指令是不合法的? (12) 。 ①MOV[SI)，[DI] ②IN AL，DX ③JMP WORD PTR[BX] ④PUSH WORD PTR 10[BX+2]