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UML活动图用于系统的功能建模，并强调对象间的控制流。在以下4种UML图形中，（）是一个UML活动图。

某数据处理流水线如图所示，若每隔3Δt流入一个数据，连续处理4个数据。此数据处理流水线的实际吞吐率为（）。

若某分页管理的虚拟存储器共有8个页面，每页为1024个字节，实际主存为4096个字节，采用页表法进行地址映像。若页表的内容如下表所示，则虚拟地址1023所对应的主存实地址为（）。
某分页管理系统的页表

某软件公司欲构造一文件/目录树，采用（）进行设计所得类图如图所示。

若对表A按（）进行运算，可以得到表B。

系统中有R类资源m个，现有n个进程互斥使用。若每个进程对R资源的最大需求为w，那么当m、n、w取下表中的数值时，对于表中的a～e共5种方案，（）可能会发生死锁。

如图a所示是某一个时刻J₁、J₂、J₃、J₄共4个作业在内存中的分配情况，若此时操作系统先为J₅分配5KB空间，接着又为J₆分配10KB空间，那么操作系统采用分区管理中的（）算法，使得分配内存后的情况如图b所示。

若某航空公司的飞机订票系统有n个订票终端，系统为每个订票终端创建一个售票终端的进程。假设P_i（i=1，2，…，n）表示售票终端的进程，H_j（j=1，2，…，m）表示公共数据区，分别存放各个航班的现存票数，Temp为工作单元。P_i进程的工作流程如图所示，a、b和c处将执行P操作和V操作，则图中a、b和c应分别填入（）。

下图是一个软件项目的活动网络图，其中项点表示项目里程碑，边表示包含的活动，边上的权重表示活动的持续时间（单位：天），则项目总工期为（）天。
 

某系统集成项目为满足某种软件产品的市场需求，拟提出自主开发、部分研发任务外包和外购3个方案。假设各方案中销路好的概率为0.3，销路一般的概率为0.5，销路差的概率为0.2。不同销路的损益值如下表所示。假设该项目经营期为10年，那么该项目所作的决策最可能是（）。

某系统集成公司为做好项目风险管理，给风险定义了风险严重性、风险可能性、风险系数3个参数。其中，风险系数是风险严重性和风险可能性的乘积。
该公司对项目进度延误、费用超支的风险严重性等级和风险可能性等级的定义如下表所示。

假定该企业将风险系数大于等于10的情况定义为红灯状态，需要优先处理，则下列（）的情况属于红灯状态。

如图所示中UML类图的设计模式的意图是（65）。在（66）情况中，应该使用该设计模式。

Pharming is a scamming practice in which malicious code is installed on a personal computer or server, misdirecting users to （71） Web sites without their knowledge or consent. Pharming has been called"phishing without a lure".
In phishing, the perpetrator sends out legitimate-（72） e-mails, appearing to come from some of the Web’s most popular sites, in an effort to obtain personal and financial information from individual recipients. But in pharming, larger numbers of computer users can be （73） because it is not necessary to target individuals one by one and no conscious action is required on the part of the victim. In one form of pharming attack, code sent in an e-mail modifies local host flies on a personal computer. The host files convert URLs into the number strings that the computer uses to access Web sites. A computer with a compromised host file will go to the fake Web site even if a user types in the correct Internet address or clicks on an affected （74） entry. Some spyware removal programs can correct the corruption, but it frequently recurs unless the user changes browsing （75）.

设有员工实体Employee(employeeID,name,sex,age,tel,department)，其中employeeID为员工号，name为员工姓名，sex为员工性别，age为员工年龄，tel为员工电话(要求记录该员工的手机号码和办公室电话)，departID为员工所在部门号(要求参照另一部门实体Department的主码departID)。
Employee实体中存在的派生属性及其原因是（69）；对Employee实体中属性departmentID的约束是（70）。

某软件公司欲开发一个图像浏览系统，要求该系统能够显示BMP、JPEG和GIF共3种格式的文件，并且能够在Windows和Linux两种操作系统上运行。系统首先将相关图片格式的文件解析为像素矩阵，然后将像素矩阵显示在屏幕上。为满足上述需求并减少所需生成的子类数目，采用（67）进行设计所得的类图如图所示。假设该系统需要支持8种格式的图像文件和4种操作系统，不考虑类Matrix，若采用该设计模式则至少需要设计（68）个类。

RSA是一种公开密钥加密算法。假定表示利用X的密钥Y对消息M进行加密，表示利用X的密钥Y对消息M进行解密，其中Y=P表示公钥，Y=S表示私钥。A利用RSA进行数字签名的过程可以表示为（63），A利用RSA实施数字签名后不能抵赖的原因是（64）。

63（）

如图所示中UML类图的设计模式的意图是（65）。在（66）情况中，应该使用该设计模式。

Pharming is a scamming practice in which malicious code is installed on a personal computer or server, misdirecting users to （71） Web sites without their knowledge or consent. Pharming has been called"phishing without a lure".
In phishing, the perpetrator sends out legitimate-（72） e-mails, appearing to come from some of the Web’s most popular sites, in an effort to obtain personal and financial information from individual recipients. But in pharming, larger numbers of computer users can be （73） because it is not necessary to target individuals one by one and no conscious action is required on the part of the victim. In one form of pharming attack, code sent in an e-mail modifies local host flies on a personal computer. The host files convert URLs into the number strings that the computer uses to access Web sites. A computer with a compromised host file will go to the fake Web site even if a user types in the correct Internet address or clicks on an affected （74） entry. Some spyware removal programs can correct the corruption, but it frequently recurs unless the user changes browsing （75）.

设有员工实体Employee(employeeID,name,sex,age,tel,department)，其中employeeID为员工号，name为员工姓名，sex为员工性别，age为员工年龄，tel为员工电话(要求记录该员工的手机号码和办公室电话)，departID为员工所在部门号(要求参照另一部门实体Department的主码departID)。
Employee实体中存在的派生属性及其原因是（69）；对Employee实体中属性departmentID的约束是（70）。

某软件公司欲开发一个图像浏览系统，要求该系统能够显示BMP、JPEG和GIF共3种格式的文件，并且能够在Windows和Linux两种操作系统上运行。系统首先将相关图片格式的文件解析为像素矩阵，然后将像素矩阵显示在屏幕上。为满足上述需求并减少所需生成的子类数目，采用（67）进行设计所得的类图如图所示。假设该系统需要支持8种格式的图像文件和4种操作系统，不考虑类Matrix，若采用该设计模式则至少需要设计（68）个类。

RSA是一种公开密钥加密算法。假定表示利用X的密钥Y对消息M进行加密，表示利用X的密钥Y对消息M进行解密，其中Y=P表示公钥，Y=S表示私钥。A利用RSA进行数字签名的过程可以表示为（63），A利用RSA实施数字签名后不能抵赖的原因是（64）。

Pharming is a scamming practice in which malicious code is installed on a personal computer or server, misdirecting users to （71） Web sites without their knowledge or consent. Pharming has been called"phishing without a lure".
In phishing, the perpetrator sends out legitimate-（72） e-mails, appearing to come from some of the Web’s most popular sites, in an effort to obtain personal and financial information from individual recipients. But in pharming, larger numbers of computer users can be （73） because it is not necessary to target individuals one by one and no conscious action is required on the part of the victim. In one form of pharming attack, code sent in an e-mail modifies local host flies on a personal computer. The host files convert URLs into the number strings that the computer uses to access Web sites. A computer with a compromised host file will go to the fake Web site even if a user types in the correct Internet address or clicks on an affected （74） entry. Some spyware removal programs can correct the corruption, but it frequently recurs unless the user changes browsing （75）.

Pharming is a scamming practice in which malicious code is installed on a personal computer or server, misdirecting users to （71） Web sites without their knowledge or consent. Pharming has been called"phishing without a lure".
In phishing, the perpetrator sends out legitimate-（72） e-mails, appearing to come from some of the Web’s most popular sites, in an effort to obtain personal and financial information from individual recipients. But in pharming, larger numbers of computer users can be （73） because it is not necessary to target individuals one by one and no conscious action is required on the part of the victim. In one form of pharming attack, code sent in an e-mail modifies local host flies on a personal computer. The host files convert URLs into the number strings that the computer uses to access Web sites. A computer with a compromised host file will go to the fake Web site even if a user types in the correct Internet address or clicks on an affected （74） entry. Some spyware removal programs can correct the corruption, but it frequently recurs unless the user changes browsing （75）.

Pharming is a scamming practice in which malicious code is installed on a personal computer or server, misdirecting users to （71） Web sites without their knowledge or consent. Pharming has been called"phishing without a lure".
In phishing, the perpetrator sends out legitimate-（72） e-mails, appearing to come from some of the Web’s most popular sites, in an effort to obtain personal and financial information from individual recipients. But in pharming, larger numbers of computer users can be （73） because it is not necessary to target individuals one by one and no conscious action is required on the part of the victim. In one form of pharming attack, code sent in an e-mail modifies local host flies on a personal computer. The host files convert URLs into the number strings that the computer uses to access Web sites. A computer with a compromised host file will go to the fake Web site even if a user types in the correct Internet address or clicks on an affected （74） entry. Some spyware removal programs can correct the corruption, but it frequently recurs unless the user changes browsing （75）.