计算机网络小题翻译
网络小题练习题：
1. In TCP, the acknowledgement number that a host puts in a segment（段）is the sequence（序列，顺序）number of the next byte（字节）the host is expecting from the sender.
2. There are two fundamental （基（根）本的）approaches （接近，通往的方法）to moving data through a network of links and switches（交换机）:
circuit switching（线路交换） and packet switching（包交换）.
有两种基本途径移动数据通过网络的链接和开关:电路交换和分封交换
3. Switch（交换机）is usually used to separate（分开，隔开）collision
domains（碰撞域，冲突域）.
开关通常是用来分离冲突域
4. The length of an IPv6 address is 128 bits.
IPv6的长度的地址是一个128位。
5. Generally, there are two types of network routing（路由选择）
algorithms（算法）: distance vector（距离矢量路由协议） and Link State（链路状态路由协议）.
一般来说,有两种类型的网络路由算法:距离向量和链路状态
6. The network portion（部分，一部分） of an IP address is the same for all the hosts on the same IP network.
网络部分(部分,一部分)的一个IP地址是同为所有的主机在同一IP网络
7. Compared with Stop-and-Wait（停止等待协议）, which is a non-
pipelined reliable data transfer protocol(协议), two pipeline-based reliable data transfer approaches are go-back-n （倒退N协议）and Selective Repeat (SR)（选择重传）.
Stop-and-Wait相比,这是一个可靠的数据传送协议爆炸,两pipeline-based可靠的数据传输方法和选择性go-back-n重复(SR)。
8. Two parties often use public-key encryption（数据加密） to agree on a
shared one-time symmetric session key.
双方同意经常使用公钥加密在分享一次性对称的会话密钥。
9. 10BaseT Ethernet（以太网） use twisted pair（双绞线） copper（铜）
as physical media.
10 BaseT使用铜绞线以太网物理媒体
10. With a datagram（数据报）network layer, each packet carries the
address of the destination host（目的主机）.
与一个相应的网络层,每个包携带目的地主机的地址。
11. In a Link-State routing（路由选择） algorithm（算法）, each node（节
点）has a map of the entire network and determines the shortest path from itself to all other nodes in the network.
链路状态路由算法中,每个节点有一个地图,它决定了整个网络最短路径从自身所有其他节点的网络。
12. Typically, a wireless（无线的） network with "infrastructure" includes
base stations（基点）.
通常情况下,一个无线网络基站的“基础设施”包括
13. With non-pipelined persistent mode between the browser（浏览器）
and the Web server（服务器）, it is possible for the browser to send two distinct（不同的） HTTP request messages over one TCP connection.
持续的模式和爆炸在浏览器和服务器之间,它可能两种截然不同的浏览器发送HTTP请求一个TCP 连接信息。
14. We usually refer to transport layer packets as segments, refer to link
layer packets as frame（一次定格）.
我们通常指的是传输层段包,请参阅链路层数据包的帧。
15. There are three general categories of shared media multiple（多重的）
access protocols: Channel Partition, random access and Taking Turns.
有三个一般类共享介质多址接入协议:通道分离、随机存取和轮流等。
16. The MAC protocol （协议）in 802.11 wireless network is CSMA/CA,
and here “CA” stands for collision avoidance（避免碰撞）.
AC协议在802.11无线网络CSMA / CA,这里的“CA”代表避碰。
17. For TCP connections with congestion（拥塞）window(CongWin) of
size W , timeout （超时）triggers（触发器） an another slow-start（慢启动）phase, resulting in Threshold (ssthresh) set to W/2 and CongWin set to 1.
TCP连接拥塞窗口(CongWin)大小的W,暂停slow-start触发另一个阶段,导致阈值ssthresh)设置为W / 2和CongWin设置为1
18. If a Web server has established 5 TCP connections with different
browsers（浏览器）, it uses a total of 6 TCP socket(s)（套接字，插口）.如果一个网络服务器建立TCP连接5不同的浏览器,它使用了一个共有六TCP插座(年代)。
19. host-to-host（主机到主机） communication the following functions does
network layer .
host-to-host沟通以下功能并网路层
20. OSI 7-layer network model is not used by the Internet.
七层的OSI网络模型不被互联网
21. Hub（集线器） can’t be used to separate collision domains.（冲突域）
集线器能不被用来分离冲突域。
22. A UDP socket（套接字，插座，插口）is identified by a 2-tuple: source
port and source IP address..
一个UDP插座经一个2-tuple:源端口和源IP地址。
23. NAT technology could help to save public IP address resource.
NAT技术有助于节省公共IP地址资源。
24. the default（默认值）mask（掩码）for class C in CIDR（无类别域间路
由） notation？
默认的面具在丙级在CIDR符号吗?
25. well-known port of SMTP？25
26. “Sequence number” is not the field in a typical IP header ？
“序列号”不是场在一个典型的IP报头吗?
27. we can use SSL to provide transport layer security .
我们可以使用SSL提供传输层安全。
28. CSMA/CD is most likely to introduce conflicts（冲突） .
CSMA / CD是最有可能引进的冲突
29. The protocol stacks implemented at the switch typically consists of 2
layers.
在协议栈的实现开关典型地由两层。
30. Two important reasons that the Internet is organized as a hierarchy of
networks（层次网络） for the purposes of routing（路由选择） are ？
两个重要原因,互联网是由一系列的网络路由的目的是什么?
31. What is the last address of a block of classless addresses if one of the
addresses is 12.2.2.127/28?
什么是最后一次演讲一块阶级地址的如果有一个12.2.2.127/28地址吗?
32. The 802.11 protocol does not implement collision detection because
…？
802.11协议并不实现碰撞检测,因为…?
33. In order to show current network connections in your system, you
should use command ？（实验一）
为了展示当前网络连接在您的系统,你应该使用命令呢?
34. In Selective Repeat ARQ, if packets 0~4 are sent, but only packet 1 is
acknowledged, when packet 0 and 2 timeout（超时，暂时休息）simultaneously（同时）, how many packet(s) should be retransmitted？在选择性重复ARQ,如果包0 ~ 4是送去,但是只有包1被确认,当包0和2暂停同时,多少包(s)应被重传?
35.Given the following lines from a Java program segment:
Socket connectionSocket;
ServerSocket listenSocket = new ServerSocket(7890);
Which code could be used to establish an incoming connection with a requesting host?
给下列线路从java程序:
插座connectionSocket;
ServerSocket listenSocket =新ServerSocket(7890);
哪些代码可以被用来建立一个进料连接在一个请求主人?
【计算机专业文献翻译】计算机网络
附录1英文及其译文 Computer Networks Network Goals Some reasons are causing centralized computer systems to give way to networks. The first one is that many organizations already have a substantial number of computers in operation, often located far apart .Initially, each of these computers may have worked in isolation from the other ones, but at a certain time, and management may have decided to connect them to be able to correlate information about the entire organization. Generally speaking, the goal is to make all programs, data, and other resources available to anyone on the network without regard to the physical location of the resource and the user. The second one is to provider high reliability by having alternative sources of supply. With a network, the temporary loss of a single computer is much less serious, because its users can often be accommodated elsewhere until the service is restored. Another important reason for distributing computing power has to do with the relative price of computing versus communication. Now the cost of a small computer is negligible, so it becomes attractive to analyze the data at where it is captured, and only to send occasional summaries back to the computer center, to reduce the communication cost, which now represents a larger percentage of the total cost than it used to. Yet another reason of setting up a computer network is that a computer network can provider a powerful communication medium among widely separated people. Application of Networks One of the main areas of potential network use is access to remote data bases. It may someday be easy for people sitting at their terminals
变速器论文中英文对照资料外文翻译文献
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齿轮并将它锁定输出轴上，动力经输入轴、中间轴和输出轴上的1档齿轮，1档齿轮带动输出轴，输出轴将动力传递到传动轴上（红色箭头）。典型1档变速齿轮传动比是3:1,也就是说输入轴转3圈，输出轴转1圈。 当汽车增速司机选择2档时，拨叉将1/2档同步器与1档分离后接合2档齿轮并锁定输出轴上，动力传递路线相似，所不同的是输出轴上的1档齿轮换成2档齿轮带动输出轴。典型2档变速齿轮传动比是2.2:1，输入轴转2.2圈，输出轴转1圈，比1档转速增加，扭矩降低。 当汽车加油增速司机选择3档时，拨叉使1/2档同步器回到空档位置，又使3/4档同步器移动直至将3档齿轮锁定在输出轴上，使动力可以从轴入轴—中间轴—输出轴上的3档变速齿轮，通过3档变速齿轮带动输出轴。典型3档传动比是1.7:1，输入轴转1.7圈，输出轴转1圈，是进一步的增速。 当汽车加油增速司机选择4档时，拨叉将3/4档同步器脱离3档齿轮直接与输入轴主动齿轮接合，动力直接从输入轴传递到输出轴，此时传动比1:1，即输出轴与输入轴转速一样。由于动力不经中间轴，又称直接档，该档传动比的传动效率最高。汽车多数运行时间都用直接档以达到最好的燃油经济性。 换档时要先进入空档，变速器处于空档时变速齿轮没有锁定在输出轴上，它们不能带动输出轴转动，没有动力输出。 一般汽车手动变速器传动比主要分上述1－4档，通常设计者首先确定最低（1档）与最高（4档）传动比后，中间各档传动比一
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机械毕业设计英文外文翻译436手动变速器 (2)
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计算机网络体系结构外文翻译
附录A With the new network technology and application of the continuous rapid development of the computer network should. Use of becoming increasingly widespread, the role played by the increasingly important computer networks and human. More inseparable from the lives of the community's reliance on them will keep growing. In order for computers to communicate, they must speak the same language or protocol. In the early days of networking, networks were disorganized in many ways. Companies developed proprietary network technologies that had great difficulties in exchanging information with other or existing technologies; so network interconnections were very hard to build. To solve this problem, the International Organization for Standardization（ISO）created a network model that helps vendors to create networks compatible with each other. Finding the best software is not easy. A better understanding of what you need and asking the right questions makes it easier. The software should be capable of handling challenges specific to your company. If you operate multiple distribution centers, it may be beneficial to create routes with product originating from more than one depot. Few software providers though, are capable of optimizing routes using multiple depots. The provider should be able to support installation of its product. Make sure to clearly understand what training and software maintenance is offered. Obviously, selecting the right routing/scheduling software is critically important. Unfortunately, some companies are using software that may not be best suited to their operation. Logistics actives with responsibility for approving the software ought to be comfortable they've made the right decision. It is important to realize that not all routing/scheduling software is alike！ There questions to ask are：Which operating system is used？How easy is the software to use？Here is a good way to tell. Ask if its graphical user interface（GUI）is flexible. Find out about installation speed - how long does it take？Is the software able to route third party customers with your core business？When was the software originally released and when was it last upgraded？ In 1984, ISO released the Open Systems Interconnection（OSI）reference model,
计算机网络中英文互译
AN (Access Network) 接入网 ADSL (Asymmetric Digital Subscriber Line)：非对称数字用户线 ADSL (Asymmetric Digital Subscriber Line)：非对称数字用户线 ATU (Access Termination Unit) 接入端接单元 ARP (Address Resolution Protocol) 地址解析协议 ARQ (Automatic Repeat reQuest) 自动重传请求 BER (Bit Error Rate) 误码率 CBT (Core Based Tree) 基于核心的转发树 CIDR (Classless Inter-Domain Routing) 无分类域间路由选择 DSL (Digital Subscriber Line) 数字用户线 DMT (Discrete Multi-Tone) 离散多音调 DSLAM (DSL Access Multiplexer) 数字用户线接入复用器 DVMRP (Distance Vector Multicast Routing Protocol) 距离向量多播路由选择协议EGP (External Gateway Protocol外部网关协议 FTTH (Fiber To The Home) 光纤到家 FTTB (Fiber To The Building) 光纤到大楼 FTTC (Fiber To The Curb) 光纤到路边 FCS (Frame Check Sequence) 帧检验序列 HDSL (High speed DSL)：高速数字用户线 IGP (Interior Gateway Protocol内部网关协议 ICMP(Internet Control Message Protocol) 网际控制报文协议 ISP (Internet Service Provider) 因特网服务提供者 ICMP(Internet Control Message Protocol) 网际控制报文协议 IGMP (Internet Group Management Protocol) 网际组管理协议 LCP (Link Control Protocol) 链路控制协议 LLC (Logical Link Control) 子层逻辑链路控制 LAN (Local Area Network) 局域网 MAC (Medium Access Control) 媒体接入控制 MOSPF (Multicast Extensions to OSPF) 开放最短通路优先的多播扩展 MAN (Metropolitan Area Network) 城域网 NCP (Network Control Protocol) 网络控制协议 NAT (Network Address Translation) 网络地址转换 NIC (Network Interface Card) 网络接口卡 OSPF (Open Shortest Path First) 光内部网关协议 ODN (Optical Distribution Node) 分配结点 PAN (Personal Area Network) 个人区域网 PPP (Point-to-Point Protocol) 点对点协议对等方式（P2P 方式） PIM-SM (Protocol Independent Multicast-Sparse Mode) 协议无关多播-稀疏方式PIM-DM (Protocol Independent Multicast-Dense Mode) 协议无关多播-密集方式RTO (RetransmissionTime-Out) 超时重传时间 RPB (Reverse Path Broadcasting) 反向路径广播
二轴式手动变速器外文翻译
外文翻译 文章出处《Tribology International》, 2009, 42(5):714-723 译文： 有限元热分析的陶瓷离合器 1 引言 磨料空转车辆离合器是力封闭联轴器。扭矩和高速传输被压紧表面之间产生的摩擦力所保证。应用陶瓷是因为它作为摩擦介质具有好耐热和耐磨损性能，提供了机会以驱动更高的压力，以及一个低的密度。因此，一个提功率密度启用了一个平行的最小化建筑空间。 测量使用陶瓷饰面离合器盘的第一个原型在卡尔斯鲁厄大学的一个实验室专门从事客车驱动系统进行了测试执行。在分析过程中的有限元（FE）模型是将与测量数据和测量条件的知识所构成。计算的目的是要确定在离合器盘上温度的分布以及环境中的在每一时刻的及时测量目。至关重要的是熟悉的温度范围，为了检验该系统的耐磨特性。因此，重要信息从测量数据中得出。在临界负载的情况下，预计最高温度必须在时间和空间上进行预测，为保护接近发热体的位置测量工具的。 本研究的目的是分析和修改该离合器系统通过改进，以提供更好的工作条件热传导和系统或增加转化成摩擦热的能量的对流。此外，人们希望找到更有效的更好的离合器系统设计方案。 计算是由宇宙星空的设计的软件进行的。在模型开发阶段，非常谨慎，必须采取几何元素，选择适当的简化尺寸，并且由于正确调整的时间步长大量的硬件要求瞬态计算。热物性参数的改变，如表面热对流化系数和热负荷，必须考虑到到在一个持续的基础上在时间和地点方面。离合器系统的分析测试这两方面，只能通过加热隔板连接的两个独立的模型来管理，根据该假说认为，接触温度必须是在两个相同的双方，同时他们要有适当接触，其价值需通过迭代来进行调整。计算显示，该热分区按周期变化，它沿不同的内，外接触环。在不同的冷却特性下，在陶瓷和钢之间的结果是不同的，热流从陶瓷侧面向钢侧流动。此热流也通过迭代确定;它的价值也改变了周期和不同沿着所述内和外接触环。 2 采用工程陶瓷作为摩擦材料的第一个原型机 这款检查过的离合器盘是根据“特定的陶瓷”产品而开发的，此材料的研发过程在流程在卡尔斯鲁厄大学的Institute for Product Development (IPEK)杂志上发表过。此开发过程已经具有的可能性，用于连接到一个真实的传动轴；甚至，它为面板有一个好的初始行为起到一个很好的缓冲作用。磨料配件必须符合以下基本要求：
计算机网络外文翻译
附录 一、英文原文： The NetWorks Birth of the Net The Internet has had a relatively brief, but explosive history so far. It grew out of an experiment begun in the 1960's by the U.S. Department of Defense. The DoD wanted to create a computer network that would continue to function in the event of a disaster, such as a nuclear war. If part of the network were damaged or destroyed, the rest of the system still had to work. That network was ARPANET, which linked U.S. scientific and academic researchers. It was the forerunner of today's Internet. In 1985, the National Science Foundation (NSF) created NSFNET, a series of networks for research and education communication. Based on ARPANET protocols, the NSFNET created a national backbone service, provided free to any U.S. research and educational institution. At the same time, regional networks were created to link individual institutions with the national backbone service. NSFNET grew rapidly as people discovered its potential, and as new software applications were created to make access easier. Corporations such as Sprint and MCI began to build their own networks, which they linked to NSFNET. As commercial firms and other regional network providers have taken over the operation of the major Internet arteries, NSF has withdrawn from the backbone business. NSF also coordinated a service called InterNIC, which registered all addresses on the Internet so that data could be routed to the right system. This service has now been taken over by Network Solutions, Inc., in cooperation with NSF. How the Web Works The World Wide Web, the graphical portion of the Internet, is the most popular part of the Internet by far. Once you spend time on the Web,you will begin to feel like there is no limit to what you can discover. The Web allows rich and diverse communication by displaying text, graphics, animation, photos, sound and video. So just what is this miraculous creation? The Web physically consists of your personal computer, web browser software, a connection to an Internet service provider, computers called servers that host digital data and routers and switches to direct the flow of information. The Web is known as a client-server system. Your computer is the client; the remote computers that store electronic files are the servers. Here's how it works: Let's say you want to pay a visit to the the Louvre museum website. First you enter the address or URL of the website in your web browser (more about this shortly). Then your browser requests the web page from the web server that hosts the Louvre's site. The Louvre's server sends the data over the Internet to your computer. Your web
(完整版)计算机网络课后作业以及答案(中英文对照)
Chapter1 1-11.What are two reasons for using layered protocols? (请说出使用分层协议的两个理由) 答：通过协议分层可以把设计问题划分成较小的易于处理的片段。分层意味着某一层的协议的改变不会影响高层或低层的协议。 1-13. What is the principal difference between connectionless communication and connection-oriented communication? (在无连接通信和面向连接的通信两者之间，最主要的区别是什么？) 答：主要的区别有两条。 其一：面向连接通信分为三个阶段，第一是建立连接，在此阶段，发出一个建立连接的请求。只有在连接成功建立之后，才能开始数据传输，这是第二阶段。接着，当数据传输完毕，必须释放连接。而无连接通信没有这么多阶段，它直接进行数据传输。 其二：面向连接的通信具有数据的保序性，而无连接的通信不能保证接收数据的顺序与发送数据的顺序一致。 1-20. A system has an n-layer protocol hierarchy. Applications generate messages of length M bytes. At each of the layers, an h-byte header is added. What fraction of the network bandwidth is filled with headers? (一个系统有n层协议的层次结构。应用程序产生的消息的长度为M字节。在每一层上需要加上一个h字节的头。请问，这些头需要占用多少比例的网络带宽) 答：hn/(hn+m)*100% 1-28. An image is 1024 x 768 pixels with 3 bytes/pixel. Assume the image is uncompressed. How long does it take to transmit it over a 56-kbps modem channel? Over a 1-Mbps cable modem? Over a 10-Mbps Ethernet? Over 100-Mbps Ethernet? (一幅图像的分辨率为1024 x 768像素，每个像素用3字节来表示。假设该图像没有被压缩。请问，通过56kbps的调制解调器信道来传输这幅图像需要多长时间？通过1Mbps的电缆调制解调器呢？通过10Mbps的以太网呢？通过100Mbps的以太网呢?) 答：The image is 1024*768*3 bytes or 2359296 bytes.This is 18874368 bit. At 56,000 bits/sec, it takes about 337.042 sec. At 1,000,000 bits/sec, it takes about 18.874 sec. At 10,000,000 bits/sec, it takes about 1.887 sec. At 100,000,000 bits/sec, it takes about 0.189 sec. Chapter2 2-2. A noiseless 4-kHz channel is sampled every 1 msec. What is the maximum data rate? (一条无噪声4kHz信道按照每1ms一次进行采样，请问最大数据传输率是多少？)
汽车变速器外文翻译
外文翻译 Auto Transmission First, an overview of automotive transmission and the development trend Automobile available more than a century, especially from the mass production of motor vehicles and the automotive industry since the development of large, Car has been the economic development of the world for mankind to enter the modern life and have had a tremendous impact on the immeasurable, The progress of human society has made indelible contributions to the great, epoch-making set off arevolution. From From the vehicle as a power plant using internal combustion engine to start, auto transmission has become an important component. Is Generation is widely used in automotive reciprocating piston internal combustion engine with a small size, light weight, reliable operation and the use of The advantages of convenience, but its torque and speed range of smaller changes, and complex condition requires the use of motor vehicles Traction and the speed can be considerable changes in the scope. Therefore, its performance and vehicle dynamics and economy of There are large inter-contradictions, which contradictions of modern automotive internal combustion engine by itself is insoluble. Because Here, in the automotive power train set up the transmission and main reducer in order to achieve the purpose of deceleration by moment. Speed The main function of performance: ⑴ change gear ratio of motor vehicles, and expand the wheel drive torque and rotational speed of the Fan Wai, in order to adapt to constantly changing driving cycle, while the engine in the most favorable conditions within the scope of work; ⑵no change in the direction of engine rotation, under the premise of the realization of cars driving back; ⑶the realization of the free, temporary Interruption of power transmission, in order to be able to start the engine, idling, etc.. V ariable-speed drive transmission by the manipulation of institutions and agencies. Change the transmission ratio by way of transmission is divided into There are class-type, non-stage and multi-purpose three. Have class most widely used transmission. It uses gear drive, with a number of transmission ratio setting. Stepless transmission Continuously V ariable Transmission (CVT) transmission ratio of a certain The framework of multi-level changes may be unlimited, there is a common type of power and torque (dynamic fluid-type) and so on. Continuously V ariable Transmission Transmission development is the ultimate goal, because only it can make the most economical engine in working condition Can provide the best vehicle fuel economy and optimal power in order to provide the most comfortable By the feeling. Today's CVT is a typical representative of the CVT
变速器外文资料翻译
外文资料翻译 学生姓名：常世鹏 专业班级：车辆工程07级5班 指导教师：朱天军 河北工程大学机电学院 2011 年 6 月 Dual-clutch transmission technology highlights Transmission technology motor vehicles as a whole is shifting from manual to automatic transmission development, especially at this stage of rapid development of computer technology used in variable-speed transmission system, so that the car automatic transmission technology has been rapid development. In recent years, the automotive automatic transmission there are three main types: mechanical electronic control automatic transmission (AMT), Stepless automatic transmission (CVT) automatic transmission and hydraulic machinery (AT). In the electronically controlled automatic transmission in the field of mechanical, in recent years, there is a new