学校：密云电大分校
班级：2009计算机信息管理（专）
姓名：毕华丽
学号：20097110140128
Control unit
Main articles: CPU design and Control unit
①Diagram showing how a particular MIPS architecture instruction would be decoded by the control system.
The control unit (often called a control system or central controller) manages the computer's various components; it reads and interprets (decodes) the program instructions, transforming them into a series of control signals which activate other parts of the computer. Control systems in advanced computers may change the order of some instructions so as to improve performance.
A key component common to all CPUs is the program counter, a special memory cell (a register) that keeps track of which location in memory the next instruction is to be read from.
The control system's function is as follows—note that this is a simplified description, and some of these steps may be performed concurrently or in a different order depending on the type of CPU:
1.Read the code for the next instruction from the cell indicated by
the program counter.
2.Decode the numerical code for the instruction into a set of commands
or signals for each of the other systems.
3.Increment the program counter so it points to the next instruction.
4.Read whatever data the instruction requires from cells in memory
(or perhaps from an input device). The location of this required data is typically stored within the instruction code.
5.Provide the necessary data to an ALU or register.
6.②If the instruction requires an ALU or specialized hardware to
complete, instruct the hardware to perform the requested operation.
7.
register or perhaps an output device.
8.Jump back to step (1).
Since the program counter is (conceptually) just another set of memory cells, it can be changed by calculations done in the ALU. Adding 100 to the program counter would cause the next instruction to be read from a place 100 locations further down the program. Instructions that modify the program counter are often known as "jumps" and allow for loops (instructions that are repeated by the computer) and often conditional instruction execution (both examples of control flow).
It is noticeable that the sequence of operations that the control unit goes through to process an instruction is in itself like a short computer program—and indeed, in some more complex CPU designs, there is another yet smaller computer called a microsequencer that runs a microcode program that causes all of these events to happen.
Arithmetic/logic unit (ALU)
Main article: Arithmetic logic unit
③The ALU is capable of performing two classes of operations: arithmetic and logic.
The set of arithmetic operations that a particular ALU supports may be limited to adding and subtracting or might include multiplying or dividing, trigonometry functions (sine, cosine, etc.) and square roots. Some can only operate on whole numbers (integers) whilst others use floating point to represent real numbers—albeit with limited precision. However, any computer that is capable of performing just the simplest operations can be programmed to break down the more complex operations into simple steps that it can perform. Therefore, any computer can be programmed to perform any arithmetic operation—although it will take more time to do so if its ALU does not directly support the operation. An ALU may also compare numbers and return boolean truth values (true or false) depending on whether one is equal to, greater than or less than the other ("is 64 greater than 65?").
Logic operations involve Boolean logic: AND, OR, XOR and NOT. These can be useful both for creating complicated conditional statements and processing boolean logic.
④Superscalar computers may contain multiple ALUs so that they can process several instructions at the same time.
ALUs that can perform arithmetic on vectors and matrices.
Memory
Main article: Computer data storage
⑤Magnetic core memory was the computer memory of choice throughout the 1960s, until it was replaced by semiconductor memory.
A computer's memory can be viewed as a list of cells into which numbers can be placed or read. Each cell has a numbered "address" and can store a single number. The computer can be instructed to "put the number 123 into the cell numbered 1357" or to "add the number that is in cell 1357 to the number that is in cell 2468 and put the answer into cell 1595". The information stored in memory may represent practically anything. Letters, numbers, even computer instructions can be placed into memory with equal ease. Since the CPU does not differentiate between different types of information, it is the software's responsibility to give significance to what the memory sees as nothing but a series of numbers.
In almost all modern computers, each memory cell is set up to store binary numbers in groups of eight bits (called a byte). Each byte is able to represent 256 different numbers (2^8 = 256); either from 0 to 255 or ?128 to +127. To store larger numbers, several consecutive bytes may be used (typically, two, four or eight).⑥ When negative numbers are required, they are usually stored in two's complement notation.
applications or historical contexts. A computer can store any kind of information in memory if it can be represented numerically. Modern computers have billions or even trillions of bytes of memory.
The CPU contains a special set of memory cells called registers that can be read and written to much more rapidly than the main memory area.⑦There are typically between two and one hundred registers depending on the type of CPU. Registers are used for the most frequently needed data items to
constantly being worked on, reducing the need to access main memory (which
is often slow compared to the ALU and control units) greatly increases the computer's speed.
Computer main memory comes in two principal varieties: random-access memory or RAM and read-only memory or ROM. RAM can be read and written to anytime the CPU commands it, but ROM is pre-loaded with data and software that never changes, so the CPU can only read from it. ROM is typically used to store the computer's initial start-up instructions. In general, the contents of RAM are erased when the power to the computer is turned off, but ROM retains its data indefinitely. In a PC, the ROM contains a specialized program called the BIOS that orchestrates loading the computer's operating system from the hard disk drive into RAM whenever the computer is turned on or reset. In embedded computers, which frequently do not have disk drives, all of the required software may be stored in ROM. Software stored in ROM is often called firmware, because it is notionally more like hardware than software. Flash memory blurs the distinction between ROM and RAM, as it retains its data when turned off but is also rewritable. It is typically much slower than conventional ROM and RAM however, so its use is restricted to applications where high speed is unnecessary.
⑧In more sophisticated computers there may be one or more RAM cache memories which are slower than registers but faster than main memory.
frequently needed data into the cache automatically, often without the need for any intervention on the programmer's part.
Multitasking
Main article: Computer multitasking
While a computer may be viewed as running one gigantic program stored in its main memory, in some systems it is necessary to give the appearance of running several programs simultaneously. This is achieved by multitasking i.e. having the computer switch rapidly between running each program in turn.
One means by which this is done is with a special signal called an interrupt which can periodically cause the computer to stop executing instructions where it was and do something else instead. By remembering where it was executing prior to the interrupt, the computer can return to that task later. ⑨If several programs are running "at the same time", then the interrupt generator might be causing several hundred interrupts per second, causing a program switch each time. Since modern computers
typically execute instructions several orders of magnitude faster than human perception, it may appear that many programs are running at the same time even though only one is ever executing in any given instant. This method of multitasking is sometimes termed "time-sharing" since each program is allocated a "slice" of time in turn.
Before the era of cheap computers, the principal use for multitasking was to allow many people to share the same computer.
Seemingly, multitasking would cause a computer that is switching between several programs to run more slowly —in direct proportion to the number of programs it is running. However, most programs spend much of their time waiting for slow input/output devices to complete their tasks. ⑩If a program is waiting for the user to click on the mouse or press a key on the keyboard, then it will not take a "time slice" until the event it is waiting for has occurred. This
speed loss.
生词部分
1.articles 物品
2.diagram 线图
3.particular 特别的
4.central 中央的
5.manages 经营
6.various 各种不同的
https://www.doczj.com/doc/1214875601.html,ponents 元件
8.instructions 指令
9.transforming 转变
10.performance 绩效
11.special 特别报导
12.register 记录器
13.track 轨道
14.location 位置
15.function 功能
16.description 类型
17.concurrently 并发、同时存在的
18.numerical 数值的
19.calculation 计算
20.microsequencer 微序列器
21.microcode 微代码
22.boolean 布尔数学体系的
23.graphics 图案
24.vectors 引导
25.matrices 母体
26.storage 储存
27.Magnetic 有磁性的
28.semiconductor 半导体
29.significance 重要性
30.principal 主要的
句子分析
①Diagram showing how a particular MIPS architecture instruction would be decoded by the control system.
图中显示如何解码的特定任务执行计划体系结构教学控制系统。主谓宾结构
②If the instruction requires an ALU or specialized hardware to complete, instruct the hardware to perform the requested operation.
如果指令要求算术逻辑运算器或专用的硬件才能完成，指示硬件执行请求的操作。
条件状语从句
③The ALU is capable of performing two classes of operations: arithmetic and logic.
这种算术逻辑单元能够进行两类业务：算术和逻辑。主系表结构
④Superscalar computers may contain multiple ALUs so that they can process several instructions at the same time.
超标量的计算机可以控制多个运算器运算，以便他们可以同时处理多个说明。主谓宾结构
⑤Magnetic core memory was the computer memory of choice throughout the 1960s, until it was replaced by semiconductor memory.
核心内存是在二十世纪六十年代期间的计算机内存，直到替换为半导体存储器。主系表结构
⑥ When negative numbers are required, they are usually stored in two's complement notation.
当需要负数的时候，他们通常存储在两个补充表示法。时间状语从句
⑦ There are typically between two and one hundred registers depending on the type of CPU.
通常有2到100个寄存器取决于CPU类型。There be结构
⑧In more sophisticated computers there may be one or more RAM cache memories which are slower than registers but faster than main memory. 在更复杂的计算机可能有一个或更多的RAM缓存的记忆低于寄存器但快于主内存中。状语从句
⑨If several programs are running "at the same time", then the interrupt generator might be causing several hundred interrupts per second, causing a program switch each time.
如果多个程序运行"在同一时间"，然后中断发生器可能导致每秒数以百计的中断，造成程序每次都要切换。条件状语从句
⑩If a program is waiting for the user to click on the mouse or press a key on the keyboard, then it will not take a "time slice" until the event it is waiting for has occurred.
如果程序正在等待用户单击鼠标或按键盘上的键，那么它将不会采取"时间段"，直到等事件发生。条件状语从句
中文翻译
控制单元
主要文章：CPU设计及控制单元
图中显示如何解码的特定任务执行计划体系结构教学控制系统。控制单元控制系统或中央控制器通常称为管理计算机的各种组件，它读取并解释解码程序指令，把他们变成一个激活其他地区的一系列控制信号的计算机。先进的电脑控制系统可能会改变一些说明的顺序，以提高性能。常见的一个关键组件的所有cpu是程序计数器，一种特殊的存储单元的登记，跟踪内存中的位置读取下一个指令。控制系统的功能如下：请注意，这是一个简单描述，其中的某些步骤可能会并发执行的或不同的顺序根据CPU类型：
1. 读取单元格中的下一个指令的代码所指示的程序计数器。
2. 指令的解码的数值代码设置命令或每个其他系统的信号。
3. 增量程序计数器，使其指向下一个指令。
4. 从单元格中读取指令要求的任何数据在内存中，或者从输入设备。这所需
的数据通常存储的位置在指令的代码。
5. 提供必要的数据铝或注册。
6. 如果指令要求算术逻辑运算器或专用的硬件才能完成，指示硬件执行请求的
操作。
7. 算术逻辑单元回来的结果写入内存位置或注册或者输出设备。
8. 跳到步骤1。
程序计数器以来就在概念上另一组的记忆细胞，它可以更改计算算术逻辑单元。 100添加到程序计数器会导致下一个要读取的指令从100个地点进一步程序的地方。修改程序计数器的说明，常被称为"跳跃"，并允许计算机重复循环指令和通常的条件指令的执行这两个示例控制流。是明显序列操作控制单位去通过过程教学是在本身像短计算机程序和事实上，在一些更复杂中央处理器设计，有是另一个还小计算机叫微序列器运行微码程序原因所有这些事件发生。
算术逻辑单元
主要文章：算术逻辑单元
这种算术逻辑单元能够进行两类业务：算术和逻辑。设置特定的算术逻辑单元支持的算术运算可能仅限于添加和减去或可能包括乘以或分立、三角函数的正弦、余弦和平方根。全数字整数而其他的一些只能使用有限的浮点表示实际的
数字，尽管精度。但是，可以执行的任何计算机只是简单的操作可通过编程打破更加复杂的操作简单的步骤，它可以执行。因此，任何计算机可以执行任何算术操作的程序--尽管这需要更多的时间做如果算术逻辑单元不直接支持该操作。算术逻辑单元可能也比较数字，并返回布尔值的真相值真或假，具体取决于是否等于、大于或小于另一个"64大于65的？ "。逻辑操作涉及布尔逻辑：与、或、异或，非。这些可以创建复杂的条件语句和处理的都是有用的布尔逻辑。超标量的计算机可以控制多个运算器运算，以便他们可以同时处理多个说明。图形处理器技术和多指令流的计算机可以执行的功能往往提供运算器运算算法的矢量和矩阵。
内存
主要文章：计算机数据存储
核心内存是在二十世纪六十年代期间的计算机内存，直到替换为半导体存储器。计算机内存中的列表可以查看数字可以放置或读到的单元格。每个单元都有一个编号"地址"并可以存储一个数字。计算机可以指示"把123号到单元格编号为1357"或"添加单元格中的数字1357的号码是2468和1595把答案到单元格的单元格"。在内存中存储的信息可以代表任何东西。字母、数字，即使计算机指令，也可以同样轻松地放入内存。由于CPU不区分不同类型的信息，这是软件的责任给内存所看到的意义除非一系列数字。在几乎所有的现代计算机，每个内存单元格设置为组中的存储进制数字有八个位叫字节。每个字节是能代表256个不同的数字（2-8=256）；要么从0到255或?128 到127。存储较大的数值，也可以使用连续的字节通常是（2、4、8）。当需要负数的时候，他们通常存储在两个补充表示法。其他的安排是可能的，但是通常没有看到外面的专用应用程序或历史背景。计算机可在内存中存储任何类型的信息，如果它可以表示的数值。现代计算机已经上亿，甚至数兆字节的内存。
CPU包含一组特殊的内存寄存器单元可以读取和写入远快于主内存区域。通常有2到100个寄存器取决于CPU类型。最常用的寄存器所需的数据项为避免每次访问主内存中的数据需要。随着数据不断地工作，减少了访问主内存的需要往往缓慢相比，算术和逻辑单元和控制的单位大大提高计算机的速度。
计算机内存来自两个主要品种：随机存取内存RAM和只读内存ROM。 RAM 可以读取和写入任何CPU的命令，但ROM预装载的数据和软件，永远不会改变，因此，CPU只能读取它。 ROM通常用于存储计算机的试运转的说明。通常，计算机电源关闭时内存的内容删掉了，但ROM无限期地保留其数据。在PC中，包含一个专门的项目叫做协调加载计算机的操作系统的BIOS从硬盘驱动器到内存当计算机打开或重置。嵌入式计算机中，这通常没有磁盘驱动器，可以将所有必需的软件存储在ROM。 ROM通常称为固件中存储的软件，因为它更像是名义上的硬件。 ROM和RAM之间的模糊的区别，关闭但也可擦写的时候它会保留其数据。它通常远低于传统的ROM和RAM然而，所以它的使用是受限制的高速度是不必要的应用程序。
在更复杂的计算机可能有一个或更多的RAM缓存的记忆低于寄存器但快于主内存中。通常这类的计算机设计是经常需要移动数据缓存到高速缓存中自动，通常不需要任何干预程序员的一部分。
多任务处理
主要文章：计算机任务
当计算机可以被视为一个巨大的程序存储在主内存中，在一些系统必须让同
时运行多个程序的外观。这是通过多任务即把计算机运行的每个程序之间快速切换。
一个这样做的方法是用一种特殊的信号可以定期的所谓的中断导致计算机停止执行说明在哪里，而不是做一件事。记得在执行之前中断，计算机可以返回到该任务以后。如果多个程序运行"在同一时间"，然后中断发生器可能导致每秒数以百计的中断，造成程序每次都要切换。因为现代计算机通常执行指令的几个数量级的速度比人类感知要快，虽然只有一个程序是在任何给定的时间执行，它可能也会出现许多程序是运行在相同的时间。一心多用的这种方法有时称为"分时技术法"因为每个程序分配是一个"切片"的时间段。
廉价电脑的时代之前，主要用于多任务是让许多人共享同一台计算机
从表面上看，多任务会导致多个程序之间切换的计算机运行缓慢。然而，大多数程序花太多时间等待缓慢输入输出设备来完成他们的任务。如果程序正在等待用户单击鼠标或按键盘上的键，那么它将不会采取"时间段"，直到等事件发生。这将释放其他程序来执行的时间，这样许多程序可以运行在相同的时间，而不会丢失不可接受的速度。
大学英语1考试卷 总分：100分 简答题 1、将下列句子翻译成汉语 1.We can do a lot of things onlinesuch assearching for information and communicating with friendsno matter how far.答案：我们可以在网上做很多事情，例如寻找信息及和朋友沟通，不管相距多远。 2.Some people seem tohave their own ability in learning language答案：有些人在学习语言方面似乎有自己的天赋. 3.It is necessary for them to learn the language in order to communicate with these people and to learn from them.答案：为了与这些人进行交流，向他们学习，学习这门语言是必要的 4.Our likes and dislikes, tastes and preferences that hide in our choices of such activities such as reading books, going to the cinema, camping, or certain cultural pursuits, are all related to social background and learning experiences.答案：我们的好恶、品位、喜好决定了我们是选择看书、看电影、露营或某种文化追求，这又同社会环境和学习经验有关。 5.Occasionally, for a formal party or dinner, an invitation requires an answer,either in writing or by telephone. 答案：偶尔,一个正式的聚会或晚宴, 被邀请人是需要做出明确答复的, 无论是通过书面或者电话. 选择性答案2：应邀出席正式宴会或晚餐，不管是用书面还是用电话，有时是要回复的。（意思差不多，哪个通顺写哪个吧） 6.They not only like playing or watching games, but also like talking about them, or even thinking about them. 答案：他们不仅喜欢玩游戏、看游戏，而且喜欢谈论和思考它们。 7.There are plenty out there that are good and plenty that are bad. 答案：那里有很多是好的，很多是坏的。 8.Yet putting off something we know we should do is a bad habit to get into. 答案：然而，拖延我们知道应该做的事就会染上一个坏习惯。 9.And don’t you feel stressed and worried when you have to hurry?
2017电大开放英语1形成性考核册答案（最新 无错版） 开放英语（1）形成性考核册作业1答案 选择题请在在选项上画√
1、请写出下列名词的复数形式。 Parent photo bus life half child w oman tooth Parents photos buses lives haves children women teeth 2、频度副词often,always,sometimes等在句中的位置是有规律的，请写出这些规律，并各举一个例句。 （1）在动词 to be之后： Are you always at home on Sunday? （2）在实意动词之前： I sometimes go to London. （3）在含有助动词的句子中，置于助动词之后，实意动词之前。 I do not often go to work by bus. 3、请写现在进行时的两种用法，并分别举一个例句。 （1）现在进行时表示此刻正在发生的事情或正在进行的动作。 He is talking to a customer.
（2）现在进行时也可以表示这一段时期正在进行的活动，虽然在此时此刻江没有进行。 LiJun is working on a new database at the moment ,but right now she is sleeping. 4、请用学过的功能句型介绍你自己的姓名、年龄、所在城市、工作。请用英语写（略） 开放英语（1）作业1 第一部分交际用语 1. A 2. B 3. B 4. B 5. A 第二部分词汇与结构 6. B 7. A 8. C 9 .C 10. C 11 .B 12 .B 13. C 14 .C 15. C 16. B 17. A 18. B 19. B 20. A 21. B 22. A 23. C 24. C 25. A 第三部分句型变换 26. He is a manager. Is he a manager? 27. She usually goes to work by bus. Does she usually go to work by bus? 28. There are fifty students in the class. Are there fifty students in the class? 29. They have a large house.
专业英语大作业 一：英译汉 翻译范围TCP/IP Illustrated, V olume 1: The Protocols 5.1~5.5 15.1~15.2 第5章RARP：逆地址解析协议 5.1简介 5.2 RARP报文格式 5.3 RARP示例 5.4 RARP服务的设计 5.5小结 练习 5.1简介 一个拥有本地磁盘的系统通常是从磁盘文件读取配置文件中获取其IP地址。但一个没有磁盘的系统，如X终端或无盘工作站，需要一些其它方式去获得其IP地址。 每个系统在网络上都有一个唯一的硬件地址，由网络接口的制造商分配。 RARP的原则是无盘系统从接口卡上读取其独特的硬件地址，并发送RARP请求（网络上的广播帧）要求别人对无盘系统的IP地址（使用RARP回应）进行应答。 虽然这个概念很简单，执行往往比ARP更难，在本章后面会描述其原因。 RARP的正式规范是RFC 903。 5.2 RARP报文格式 RARP报文的格式几乎与ARP报文是相同的（图4.3）。唯一的区别是，RARP 的请求或应答帧类型为0×8035，并且在操作层RARP请求值为3、RARP应答值为4。 图4-3 ARP在网络上请求与应答报文的格式 与ARP一样，RARP服务器请求是广播和RARP应答通常是单播。 5.3 RARP示例 在我们的网络，我们可以强制sun主机从网络引导，而不是它的本地磁盘。 如果我们在主机bsdi上运行RARP服务器和tcpdump，我们得到如图5.1所示的输出。我们使用-e参数去标记tcpdump的打印硬件地址：
图5.1 RARP请求和应答。 该RARP请求是广播（1号线）的，第2行的RARP应答是单播的。第2行的输出，“at sun”,意味着RARP应答包含了主机sun（140.252.13.33）的IP地址。 在第3行，我们看到，一旦sun接收其IP地址，它会发出一个TFTP读请求（RRQ）的文件8CFCOD21.SUN4C。（TFTP是简单文件传输协议，我们在第15章进行详细描述）。在文件名中的8个十六进制数字是sun主机的IP地址140.252.13.33的十六进制表示形式。这是在RARP应答中返回的IP地址。该文件名的其余部分，后缀SUN4C表示系统正在引导的类型。 Tcpdump表示第3行是一个长度为65的IP数据报，而不是一个UDP数据报（实际上它确实是），因为我们运行tcpdump命令使用-e参数，看硬件级别的地址。另一点，在图5.1要注意的是在第2行的以太网帧的长度似乎比最小较短（我们所说的是在4.5节60字节）。原因是我们的系统，该系统上运行的tcpdump 发送该以太网帧（BSDI）。该应用程序rarpd，写42字节到BSD分组过滤器装置（14字节的以太网报头和28字节的RARP应答），这是什么的tcpdump收到的副本。但以太网设备驱动程序垫这个短帧的最小尺寸为传输（60 ）。如果我们在另一个系统上已经运行的tcpdump ，长度会是60。 我们可以看到在这个例子，当这种无盘系统接收在RARP应答它的IP地址，它会发出一个TFTP请求来读取一个引导映像。在这一点上，我们不会进入其他详细介绍无盘系统是如何引导自己。（第16章介绍了使用RARP ，BOOTP和TFTP无盘X终端的引导顺序。） 图5.2表示出了如果有在网络上没有RARP服务器所得到的数据包。每个数据包的目的地址为以太网的广播地址。以太网地址跟随的是目标硬件地址，并按照发送端的硬件地址发送。
10108 大学英语（B） 一、单选题 What is NOT mentioned in US education system?（B） 选择一项： A. major courses B. teaching methods C. self-discipline of the students D. comparison with Chinese students 2.Which of the following statements is TRUE?（C） 选择一项： A. There are fewer and fewer universities and private colleges in America. B. The academic advisor is in charge of the student's living conditions. C. Required core classes are taken in the first school year. D. The student must stick to his majors throughout his college time. 3.About the courses in US colleges, which of the following is NOT TRUE?（C） 选择一项： A. Subjects of arts, sciences and languages are taken by most first year students. B. There are a number of other courses for students to choose from besides their major ones. C. Students would still get certain credits if they do not attend the courses. D. A typical course load means the credits of courses a student has for one semester. 4.If students have problems in finding jobs, they can turn to _____ for help.（B） 选择一项： A. academic advisors B. the Career Counseling and Placement Office C. some fraternities D. no organization 5.The successful college students probably are the following EXCEPT______.（A） 选择一项： A. self-centered B. active members of society during school C. members of some fraternities D. those who know how to control themselves 6.The fact that wife beating was legal in America in 1850 shows that ____C______. 选择一项： A. America's legal system was in favor of the husband B. American husbands didn't love their wives C. American wives were servants to their husbands
开放英语I（1）作业1 （Unit 1~6） 第一部分交际用语（10分） 1－5题: 阅读下面的小对话，判断稚是否恰当，恰当的选A（Right），不恰当的选B（Wrong）,并将答案写在各题前的（）中。（每题2分，共10分） (A) 1.－How old is the manager? -- He is 35 year old. A. Right B. Wrong (A) 2. – What do they do ? -- They work in a bank. A Right B. Wrong (B) 3. –Would you like some crisps? - No, I’m sorry.. A. Right B. Wrong (B) 4. – How much does the flat cost a month? - It’s on the tenth floor. A. Right B. Wrong (A) 5. – Could you sign the register, please? - Of course. A. Right B. Wrong 第二部分词汇与结构（40分） 6~25小题：阅读下面的句子，选择正确答案，并将所选项的字母符号写在各题前的（）中。（每题2分，共40分） （B）6. He _____ for an IT company. A. work B. works C. working (A) 7. I have coffee _____ breakfast time A. at B. in C. on (C) 8. _____ name is Wanghua. A. He B. He’s C. His (C) 9. She is _______ only accountant in my son’s company. A. a B. an C. the (C) 10. Maria often has a walk with _______ parents in the morning. A. she B. their C. her (B) 11. _________ you got any family ? A. Do B. Have C Has (B) 12. He’s responsible _____ the central computer system. A. in B. for C. of (C) 13. The Business Banking Department is on ____ floor. A. second B. the two C. the second (C) 14. Wang Li is _______ a new market campaign at the moment. A. plan B. planing C. planning (C) 15. Polly enjoys ________ the guitar in a band in her free time.
《自动化专业英语》翻译大作业 所选文字出处：选自论文《PLC的发展和应用》 班级：学号：姓名：成绩： PLC全名为可编程控制器，定义是种数字运算操作的电子系统，专为在工业环境应用而设计的，主要结构由电源，中央处理单元，存储器，输入输出接口电路，功能模块，通信模块组成。PLC具有通用性强、使用方便、适应面广、抗干扰性强、编程简单等特点，在军事、国防、航空航天、交通、工业生产中的地位，在可预见的将来中是无法取代的。PLC有很多流派，我国的PLC研发、生产和应用发展很快，尤其在应用方面更为突出。 PLC的发展历程和主要流派 在工业生产过程中，大量的开关量顺序控制，它按照逻辑条件进行顺序动作，并按照逻辑关系进行连锁保护动作的控制，及大量离散量的数据采集。传统上，这些功能是通过气动或电气控制系统来实现的。1968年美国GM（通用汽车）公司提出取代继电气控制装置的要求，第二年，美国数字公司研制出了基于集成电路和电子技术的控制装置，首次采用程序化的手段应用于电气控制，这就是第一代可编程序控制器，称Programmable Controller（PC）。个人计算机（简称PC）发展起来后，为了方便，也为了反映可编程控制器的功能特点，可编程序控制器定名为Programmable Logic Controller（PLC），现在，仍常常将PLC简称PC。PLC的定义有许多种。国际电工委员会（IEC）对PLC的定义是：可编程控制器是一种数字运算操作的电子系统，专为在工业环境下应用而设计。它采用可编程序的存贮器，用来在其内部存贮执行逻辑运算、顺序控制、定时、计数和算术运算等操作的指令，并通过数字的、模拟的输入和输出，控制各种类型的机械或生产过程。可编程序控制器及其有关设备，都应按易于与工业控制系统形成一个整体，易于扩充其功能的原则设计。上世纪80年代至90年代中期，是PLC发展最快的时期，年增长率一直保持为30~40%。在这时期，PLC在处理模拟量能力、数字运算能力、人机接口能力和网络能力得到大幅度提高，PLC逐渐进入过程控制领域，在某些应用上取代了在过程控制领域处于统治地位的DCS系统。在世界上200多家PLC厂商，400多品种的PLC产品大体可以按地域分成三个流派：一个流派是美国产品，一个流派是欧洲产品，还有一个流派是日本产品。同一地区的产品相互借鉴的比较多，相互影响比较大，技术参透比较深，面临的主要市场相同，拥护要求接近，这一切就使得同一地域的PLC产品表现出比较多的相似性。美国PLC技术的形成与欧洲PLC技术的形成是在相互隔离的情况下，独自研究开发获得的，因此美国的PLC产品与欧洲的PLC产品常表现出来明显的差异性。日本的PLC技术是由美国引进的，因此日本的产品对美国的产品有一定的继承性。世界上比较先进的PLC生产厂家有德国的的西门子、日本的三菱、美国的A-B公司等等。
电大开放英语《一》（1）形成性考核 册开放英语（1）作业1 第一部分交际用语（10分） 1一5小题：阅读下面的小对话，选择正确答案，并将所选项的字母符号写在各题前的（）中，红色为参考答案。（每题2分，共10分） （A）1．— How old is the manager? — He is 35 years old. A. Right. B. Wrong. （A）2．— What do they do? — They work in a bank. A. Right. B. Wrong. （B）3．— Would you like some crisps？ —No, I’m sorry. A. Right. B. Wrong. （B）4．— How much does the flat cost a month？ —It’s on the tenth floor. A. Right. B. Wrong. （A）5．— Could you sign the register, please?.
— Of course. A. Right. B. Wrong. 第二部分词汇与结构（40分） 6-25小题：阅读下面的句子，选择正确答案，并将所选项的字母符号写在各题前的（）中。（每题2分，共40分） （ B ）6. He __________ for an IT company. A. work B. works C. working （ A ）7. I have coffee _______ breakfast time. A. at B. in C. on （ C ）8. ______ name is Wanghua. A. He B. He’s C. His （ C ）9. She is _______ only accountant in my son's company. A. a B. an C. the （ C ）10. Maria often has a walk with ________parents in the morning. A. she B. their C. her （ B ）11. ___________ you got any family?
1、(5) Which of the following is not true? ADick stayed at a nice hotel in the center of the city. BDick didn't work on the first night of his arrival. CDick forgot to send his wife a telegram. DDick wanted to go back to his hotel in a taxi. 正确答案C 2、题目Reading comprehension 1(4) Who would send him the name and address of his hotel? AThe manager of his hotel. BThe police office. CThe taxi driver. DHis wife.
正确答案D 3、题目Reading comprehension 1(3)Where did Dick stay in New York? A In the center of the city. BIn a hotel. CIn a restaurant. DAt his friend's house. 正确答案B 4、题目Reading comprehension 1(2) Why did his wife want a telegram from him? ABecause she didn’t know his address yet
BBecause she wanted to go to New York, too CBecause she might send him another telegram DBecause she couldn't leave her husband by himself in New York. 正确答案A 5、1) Dick flew to New York because _________. Ahe went there for a holiday Bhe had work there Che went there for sightseeing D his home was there 正确答案B
大学英语三离线作业答 案 Document serial number【NL89WT-NY98YT-NC8CB-NNUUT-NUT108】
离线作业试卷列表2 一、单选? 1.第一部分：交际用语（共5小题；每小题3分，满分15分）- Would you be interested in seeing a film tonight- ____C______?分值：3 A. Not at all.??? B. Are you sure??? C. Great! I'd love to ??? D. You're welcome.???? 2.第一部分：交际用语（共5小题；每小题3分，满分15分）- Excuse me, could you tell me the way to P eople's Square- ____B______?分值：3 A. I don't understand you.??? B. Sorry, I'm a stranger here.??? C. Why don't you take a taxi??? D. Don't bother me.???? 3.第四部分：完形填空（共10小题；每小题1分，满分10分）30?C 分值：1 A. on mind??? B. in heart??? C. in mind??? D. on your mind???? 4.第四部分：完形填空（共10小题；每小题1分，满分10分）29 B?分值：1 A. with??? B. for??? C. to??? D. in???? 5.第四部分：完形填空（共10小题；每小题1分，满分10分）28 B?分值：1 A. impossible??? B. wonderful??? C. incapable??? D. practical???? 6.第一部分：交际用语（共5小题；每小题3分，满分15分）- I've got the first prize in the dancing ____C______?分值：3 A. You're welcome.??? B. It's very kind of you.??? C. Please accept my congratulations.??? D. Oh, really, I can't believe my ears.???? 7.第一部分：交际用语（共5小题；每小题3分，满分15分）- I've passed the ___D_______?分值：3 A. What a pity!??? B. I have the examination.??? C. Come on.??? D. Congratulations.???? 8.第一部分：交际用语（共5小题；每小题3分，满分15分）- I'm suffering from a ________A__?分值：3
Abstract: In the modern society, database technology is developing rapidly, and the data information contained therein is also increasing. In the process of enterprise operation, the database system is gradually being widely applied to daily information management, which is to effectively organize and utilize the massive information in the database through relevant technical means to help relevant data owners find valuable information and knowledge. Guide the development planning of the enterprise and improve the operational efficiency of the enterprise. This has become one of the hot topics of current e-commerce industry operators, and data mining technology can help e-commerce operators solve such problems. Data mining is a comprehensive use of related technologies such as artificial intelligence and natural language understanding. The purpose is to extract useful and valuable information or patterns from large amounts of data. This topic first analyzes and summarizes the research results of scholars at home and abroad, and makes a preliminary understanding of the application of data mining in e-commerce. Then it expounds the methods of data mining and e-commerce concepts and data mining. This paper also uses theoretical analysis and Case studies and other research methods, as well as questionnaire surveys of employees from different enterprises, fully discuss the difficulties in data mining technology in the field of e-commerce, the difficulties in the process of promotion, and the related methods to solve the bottleneck of e-commerce development. Research, in this way to explore the convergence of e-commerce development and data mining, and comprehensively promote the application of technological innovation. Through the research of this paper, we have an understanding of the application status of data mining technology in e-commerce. The problems and solutions can also provide a good platform for better application of data mining in e-commerce. Keywords: e-commerce; data mining; technical research; 1 Application status and development of data mining technology in e-commerce Data Mining Technology Application Overview: From a macro perspective, data mining technology is conducive to identifying and analyzing user behavior. In a larger depth and breadth, it summarizes users' consumption habits and behavioral preferences, which is beneficial to the subject and object to improve their service methods and product performance. To get a better customer experience and customer satisfaction. Data mining, as a high-level modern technology, has extremely complex logic and computational methods. The internal logic and methods also have different characteristics. According to a survey of 50 employees from different companies, data mining technology is widely used in e-commerce. In 74% of e-commerce, up to 81% of enterprises surveyed use data mining technology. The application of data mining technology in e-commerce is much higher than the percentage I expected. It can be seen that the current application is very wide.
开放英语（1）形考作业答案 作业1 第一部分交际用语 1. A 2. B 3. B 4. B 5. A 第二部分词汇与结构 6. B 7. A 8. C 9 .C 10. C 11 .B 12 .B 13. C 14 .C 15. C 16. B 17. A 18. B 1 9. B 20. A 21. B 22. A 23. C 24. C 25. A 第三部分句型变换 26. He is a manager. Is he a manager? 27. She usually goes to work by bus. Does she usually go to work by bus? 28. There are fifty students in the class. Are there fifty students in the class? 29. They have a large house. Have they a large house? / Do they have a large house? 30. He’s curren tly working on TV advertisements. Is he currently working on TV advertisements? 第四部分阅读理解 31．B 32．A 33．A 34．B 35．B 36.B 37.B 38.B 39.A 40.C 第五部分翻译41--45题：将下列英文句子翻译成中文。 41. The Meeting Rooms are on the ground floor. 会议室在一楼。 42. He ’s talking to a customer right now. 他此刻正在和一顾客讲话。 43. David usually have a sandwich in his office at lunchtime. 大卫午餐时间经常在办公室吃三明治。 44. I have a reservation for a single room. 我预定了一间单人间。 45. I’m waiting for an important telephone call from my boss in Shanghai.我在等我的上海老板的一个重要电话。 作业2 第一部分交际英语 1.A 2.B 3.B 4.A 5.A 第二部分词汇与结构 6.B 7.C 8.B 9.A 10.C 11.C 12.A 13.A 14.A 15.A 16.B 17.A 18.B 19.A 20.A 21.A 22.C 23.A 24.B 25.C 第三部分句型变换 26—30小题；将下列句子改写为否定句。 26. You can smoke in the bedrooms. You can not ( can’t ) smoke in the bedrooms. 27. It usually snows in winter in Ireland.
Exercises 1.When and where shall we ___A____. A.meet B. met C. to meet D. meeting A.You __D_____show more respect for your elders. A.can B. could C. would D. must 3. It is necessary that I ___D____ return the books to him tomorrow. A. will B. can C. may D. should 4. She __B_____ to school by school bus at eight in the morning. A. go B. goes C. went D. gone 5. What __C_____the notice say? A. is, say B. is, said C. did, say D. does, say 6. I’ll tell her after Ruby __B____. A. leave B. leaves C. left D. is leaving 7. We __D_____ the result tomorrow. A. know B. knew C. has known D. will know 8. On November 1 we __D_____ in this house for thirty years. A. live B. will have C. are living D. will have been living 9. It __B_____ to rain soon. A. is B. is going C. will D. shall 10. Mary ___C_____ a dress when she cut her finger.
Unit 1 1.—You speak very good English. — ___________________. A. No, my English is poor B. Don’t say that C. Thank you D. It’s a pleasure 2.— __________ have dinner with me this evening? —Yes. It’s very kind of you. A. Would you like to B. Don’t you like to C. Why don’t you D. Shouldn’t you 3. - I’m afraid Susan’s question made you angry. - ______. If I had been angry, I would have refused to answer. A. Do be afraid B. You are right C. Don’t worry D. Yes, it did 4.－I’m afraid I’ve got a terrible flu. －______________________. A. Never mind B. Keep away from me C. Better go and see a doctor. D. You need to be more careful 5.－It’s cold in here. Do you mind if I close the door?－______________________. A. With pleasure B. Yes, please C. Of course not D. Thank you 6.－I’m going to America for a holiday next week.－______________________. A. Goodbye B. Wish you success C. For sure D. That’s great 7.－Would you like a cup of coffee? －______________________. A. It’s very kind of you. B. No, I wouldn’t C. Yes, please D. Here you are 8. －Haven't seen you for ages. _______ －I've been in California for the past month. A. What are you up to recently? B. How soon will you be back? C. What are you going to do? D. Where did you hide? 9.－Can I borrow your camera for a week?－______________________. A. Sure, here you are B. Yes, you can borrow C. Yes, bring it with you D. It doesn’t matter 10.－Sorry, I have kept you waiting. －______________________. A. That’s all right B. I don’t care C. I’m sad D. No, not at all. Unit 2 1.－Mary, your dress is really beautiful. How is John?－ . A. Thank you very much. B. No, no, John is not bad. C. Thank you. He is fine. D. Don’t say that. It’s ugly. John is good. 2.－Do you mind telling me where you’re from?－ . A. Certainly. I’m from London. B. Sure. I was born in London. C. Not really, you can do it. D. Certainly not. I’m from London. 3.－May I see t he menu, please? I’ve been waiting an hour already.－ . A. That is the menu, sir. B. Yes, please go on. C. Here you are, sir. D. Of course, sir. 4.－I was worried about chemistry, but Mr. Brown gave me an A! － . A. Don’t worry about it. B. Congratulations! That’s a difficult course. C. Mr. Brown is very good. D. Good luck to you! 5.—Did Tom tell you to water the flowers? －___________________. A. No. And so did I B. No. And neither did I C. He did. And so I did D. He did. And so do I 6.—Shall we sit up here on the grass or down there near the water? — _____________. A. I’d rather stay here if you don’t mind B. Sorry, I don’t like neither