31●IEEE802.11定义了无限局域网的两种工作模式，其中__(51)__模式是一种点对点连接，不需要无线接入点和有线网络的支持，用无线网卡连接的设备之间就可以直接通信。IEEE802.11的物理层规定了三种传输技术：即红外技术、直接序列扩频（DSSS）和频率跳动扩频（FHSS）技术，这两种扩频技术都工作在__(52)__的ISM频段。无线LAN的最小构成模块是基本服务集（BBS），它由__(53)__同一共享介质的站点组成。
A.Roaming
B.Ad Hoc
C.Infrastructure
D.DiffuseIR
开始考试练习点击查看答案32●设Mk={1，2，…，k-1}（整数k>1），Xk表示Mk上的模k乘法，则当k为__(58)__时，<Mk，Xk>不是群。
A.2
B.3
C.4
D.5
开始考试练习点击查看答案33●现需设计有6个元件的单层电路板，把6个元件分成两组，每组有三个元件，设计时要求每组中的任一个元件必须与另一组中的所有元件用导线连接，但每组内部任何两个元件之间没有导线连接。不管怎样设计，电路中导线的交叉数至少为__(60)__。
A.1
B.2
C.3
D.4
开始考试练习点击查看答案34●为了表示软件项目管理工作中各项任务之间的进度衔接关系，最常用的计划管理工具是__(64)__。
A.程序结构图
B.数据流图
C.E-R图
D.甘特（Gantt）图
开始考试练习点击查看答案35●软件项目管理一般包含以下几个方面的内容：任务划分、计划安排、经费管理、审计控制、__(65)__和项目保证等。
A.市场管理
B.用户管理
C.风险管理
D.设备管理
开始考试练习点击查看答案36●Across a wide variety of fields, data are being collected and accumulated at a dramatic pace. There is an urgent need for a new generation of computational theories and tools to assist humans in __(66)__ useful information (knowledge) from the rapidly growing __(67)__ of digital dat
A.These theories and tools are the subject of the emerging field of knowledge discovery in database (KDD) . At an abstract level, the KDD field is concerned with the development of methods and techniques for making __(68)__ of data. The basic problem addressed by the KDD process is one of mapping low-level data (witch are typically too voluminous to understand and digest easily) into other form that might be more __(69)__ (for example, a short report) , more __(70)__(for example, a descriptive approximation or model of the process that generated the data) , or more useful (for example, a predictive model for estimating the value of future cases) , At the core of the process is the application of specific data-mining methods for pattern discovery and extraction.A.expiring
B.examining
C.extracting
D.extricating
开始考试练习点击查看答案37●Public Key Infrastructure (PKI) service providers offer organizations fully integrated PKI-managed services designed to secure Intranet, Extranet, Virtual Private Network (VPN) , and e-commerce applications. PKI solutions can enable a number of security services, including strong authentication and non-repudiation of transaction. eToken enables the users of PKI systems to generate and store __(71)__ and digital certifications inside yhe token, creating a secure environment and allowing full __(72)__ operations, ensuring that users’ keys are never exposed to PC environment, eToken eliminates the need to store __(73)__ and keys on a hard disk or browser file, or to transmit them across the Internet/Extranet, assuring peace-of-mind and confidence during online communications. A digital signature is created using the private key of an individual to ensure the validity of his request. This technology can be used to guarantee __(74)__ of various transactions. The strength of either the authentication level or the digital signture relies on the level of protection offered to the private key. eToken PRO offers the maximum level of security, since it enables the use of the private key for signing and authenticating inside the eToken. The most secure use of authentication involves enclosing at least one pertificate with every signed message. The message __(75)__ verifies the certificate using the CA’s public key. If the sender’s public key is legitimate, the recipient verifies the message’s signature. Digital signatures created with a private key are verified with the digital certificate containing the public key.
A.private keys
B.public keys
C.authentication codes
D.message digests
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