《专业英语》课程论文
论文题目：Wireless sensor network node
Positioning algorithm
学院(系)：信息工程学院
专业：电子科学与技术
班级：信研135 班
学生姓名：胡剑
学号：1049721303194
教师：徐文君
2014年 5月 16 日
Wireless sensor network node positioning
algorithm
Hu jian
School of Information Engineering,
Wuhan University of Technology, Wuhan, China
434474935@https://www.doczj.com/doc/773210335.html,
Abstract- Wireless sensor networks as a new type of data acquisition technology, combined with microelectronics, wireless communications and wireless networks, such as multi-discipline, have broad application prospects in the field of industrial control, military, medical assistance, and environmental monitoring. In most applications, the physical location of the guide to the sensor node is a basic requirement, however, due to the large number of sensor nodes, randomly distributed, and the software and hardware resources are limited, so study effective positioning algorithm to determine the location of each node has an important theoretical significance and practical value.
Access to large amounts of literature on the basis of the lessons do an overview of the wireless sensor network-based positioning technology, wireless sensor networks, highlights several typical distributed positioning algorithm principle and characteristics, including Amorphous , APIT, Centroid, DV-Hop, RSSI, etc., its Matlab simulation environment simulation analysis, and compare the positioning accuracy of the various algorithms and error.
Keywords: wireless sensor networks, localization algorithm, Matlab, simulation analysis
I. INTRODUCTION
Positioning of wireless sensor networks is the wireless, self-organizing network to provide location information of nodes in the network in some way, self-organizing network localization process can be divided into self-positioning and targeting node node positioning itself to determine the coordinates of the information network node . The targeting information is needed to determine the coordinates of a target within the network coverage or an event. Node itself is the process of determining the positioning properties of the network itself, or you can use the manual calibration of various node localization algorithm to complete. Targeting the location of the network nodes is known as the reference node, the destination node determines that the event or the location in the network.
II. SYSTEM DESIGN
TIn sensor networks, most existing node localization algorithms, reference anchor nodes are positioned to take advantage of the way place. A large number of sensor nodes in the target area in the layout: a portion called the particular node, also called anchor node (beacon), which themselves can be obtained by carrying the exact location of the GPS positioning apparatus or artificial means, and have more than node powerful capabilities, but such a small proportion of nodes; node other unknown locations themselves, through their neighbor nodes to communicate to get information of each anchor nodes, these nodes using the location information as a reference, and use some calculations to get their position known to the unknown is called a node (node)
In wireless sensor networks usually used only two-dimensional coordinate system of .So long as we know from the unknown node with three anchor nodes
can calculate the position of the unknown node.
Figure 1. Schematic trilateral positioning
Assuming three anchor node coordinates are (X1,
Y1), (X2, Y2), (X3, Y3), the coordinates of the unknown node (Xu, Yu), unknown node distances from three anchor nodes are R1, R2 , R3, shown in Figure 3-2, the distance formula based on a two-dimensional coordinate system of equations can be obtained as
follows:
(1)
The above equations are usually solved using the maximum likelihood method estimates the unknown node coordinate multilateral used (Xu, Yu)：
(2)
In summary, it may obtain a plurality of unknown nodes as long as the anchor node that the unknown distance from the node to the anchor node 3 may be positioned on the practical application of the unknown node, this calculation can be different for each selected three points, and finally The results were averaged for several times and thus improve the positioning accuracy.
III. Specific positioning algorithm
A. APIT Algorithm
APIT algorithm theoretical basis is the best point inside the triangle test method PIT. PIT test principle is that if there is a direction unknown nodes simultaneously moving along this direction away from or close to three beacon nodes, then the unknown nodes located in three beacon nodes outside the triangle; otherwise unknown nodes located within the triangle. Point test using the network in a relatively high density of nodes to simulate the mobile nodes using wireless signal propagation characteristics to determine whether far or near beacon nodes within the approximate triangle, usually in a given direction, a node from another node the farther the received signal strength is weaker. Neighbor nodes exchange their received signal strength determination of a distance of beacon nodes, the nodes to move mimic PIT. B.Centroid Positioning Algorithm
Centroid algorithm, the beacon node to a neighboring node periodically broadcasts a beacon packet, a beacon packet contains the identification number and the location information of beacon nodes. When the node receives the unknown number of different beacon beacon packet from a node or reception exceeds a certain threshold time, the position of which determines its beacon nodes consisting of the centroid of the polygon.
Centroid algorithm based solely on network connectivity, and therefore relatively easy to implement. However, this method is affected by the density of the beacon nodes. Centroid algorithm for improved algorithm, density adaptive HEAP algorithm, by increasing the beacon beacon nodes nodes in a low density area in order to improve the positioning accuracy.
C. DV-Hop Positioning Algorithm
An advantage of the proposed method of ideological distance vector routing and GPS positioning. Consists of three phases: First, all nodes in the network to obtain the number of hops from a beacon node; Secondly, when obtaining the position and the other beacon nodes hop distance apart, the beacon nodes calculate the average hop distance of the network, giving their survival period, then the survival of the school with a positive value in the webcast. Unknown node receives only record the first correction, and forwarded to the neighbors. This strategy ensures that the vast majority of node receives an average hop distance from the nearest beacon node. According unknown node hops records to calculate distance to jump beacon nodes.... D. RSSI Algorithm
RSSI measurement model and the theoretical model of general experience using the signal propagation. For empirical model before the actual positioning, first select a number of test points, records the received signal strength at these points of the base stations, to establish the relationship between position and signal strength line database (x, y, ss1, ss2 respective points, ss3 ). In the actual positioning, based on the measured signal strength (ss1 ', ss2', ss3 ') and the signal strength recorded in the database by comparing the variance of the coordinates of the minimum signal strength that are used as the coordinates of the node point.
IV. The simulation results
A.
APIT Algorithm
Figure 2. Node Distribution
（300 nodes, including 60 anchor nodes, red * indicates anchor
nodes, blue O represents the unknown node ）
Figure 3. Neighbor relationship diagram
（300 nodes, including 60 anchor nodes, red * indicates anchor
nodes, red O indicates unknown node communication radius: 200m, anchor node communication radius:200m, communication model: Regular Model, the average connectivity of the network is: 31.1133, the average number of neighbor nodes of the network anchor is: 6.18）
Figure 4. Figure positioning error
（Red * indicates anchor nodes, blue O represents an estimate of
the position of the unknown node, black O that they can not be positioned unknown nodes, blue - shows the positioning error of unknown nodes (nodes connected to an unknown location and estimate the true position), a total of 300 node: 60 anchor nodes, 240 unknown nodes, 0 unknown nodes can not be located, the positioning error of 0.29857）
V. CONCLUSIONS
Five algorithms are square_random selected node distribution, GPS errors are 30m, communication radius comm-r are 200 unified communication model for the same communication model Regular Model folder, a list of error will be calculated by the five algorithms ，As shown in Figure 5:
Figure 5. Positioning deviation
Seen from the table, the maximum error and the Centroid APIT algorithm followed DV-Hop algorithm then Amorphous algorithm is the smallest error RSSI algorithm.
REFERENCES
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7. 报价书；标书；建议书proposal；quotation; bid; tender; offer 8. 图细标书评审；报价评审bid evaluation 9.标书评选表;报价评选表bid tabulation form;tabulation of bids 10.谈判negotiation 11. 厂商协调会议；协调会议vendor coordination meeting[ VCM];coordination meeting 12. 订货合约；定约成交commitment 13. 订货电传；订货通知（书）telex order；notification of commitment 14.订单（即定单）采买订单;订货合同purchase order[PO] 15. 签订合同；合同签约contract award 16. 询价；招标Inquiry;invitation to bid 17.资格预审pre-qualification 18. 合格投标商表；合格供货商表qualified bidders list;qualified 19. 询价书；招标文件Inquiry（package）;request for quotation （package）[RFQ] request for proposal [RFP]；invitation to bid[TB] 20. 请购文件；请购单requisition（package）；requisition documents 21. 采购规格书；采购说明书purchasing specification [PS] 22. 投标者须知；报价须知Instructions to bidders[TB] 23.变更change 24. 用户变更；合同变更client change；contract change 25.待定的用户变更pending client change 26.认可的用户变更approved client change
第一课 土木工程学土木工程学作为最老的工程技术学科，是指规划，设计，施工及对建筑环境的管理。此处的环境包括建筑符合科学规范的所有结构，从灌溉和排水系统到火箭发射设施。 土木工程师建造道路，桥梁，管道，大坝，海港，发电厂，给排水系统，医院，学校，公共交通和其他现代社会和大量人口集中地区的基础公共设施。他们也建造私有设施，比如飞机场，铁路，管线，摩天大楼，以及其他设计用作工业，商业和住宅途径的大型结构。此外，土木工程师还规划设计及建造完整的城市和乡镇，并且最近一直在规划设计容纳设施齐全的社区的空间平台。 土木一词来源于拉丁文词“公民”。在1782年，英国人John Smeaton为了把他的非军事工程工作区别于当时占优势地位的军事工程师的工作而采用的名词。自从那时起，土木工程学被用于提及从事公共设施建设的工程师，尽管其包含的领域更为广阔。 领域。因为包含范围太广，土木工程学又被细分为大量的技术专业。不同类型的工程需要多种不同土木工程专业技术。一个项目开始的时候，土木工程师要对场地进行测绘，定位有用的布置，如地下水水位，下水道，和电力线。岩土工程专家则进行土力学试验以确定土壤能否承受工程荷载。环境工程专家研究工程对当地的影响，包括对空气和地下水的可能污染，对当地动植物生活的影响，以及如何让工程设计满足政府针对环境保护的需要。交通工程专家确定必需的不同种类设施以减轻由整个工程造成的对当地公路和其他交通网络的负担。同时，结构工程专家利用初步数据对工程作详细规划，设计和说明。从项目开始到结束，对这些土木工程专家的工作进行监督和调配的则是施工管理专家。根据其他专家所提供的信息，施工管理专家计算材料和人工的数量和花费，所有工作的进度表，订购工作所需要的材料和设备，雇佣承包商和分包商，还要做些额外的监督工作以确保工程能按时按质完成。 贯穿任何给定项目，土木工程师都需要大量使用计算机。计算机用于设计工程中使用的多数元件（即计算机辅助设计，或者CAD）并对其进行管理。计算机成为了现代土木工程师的必备品，因为它使得工程师能有效地掌控所需的大量数据从而确定建造一项工程的最佳方法。 结构工程学。在这一专业领域，土木工程师规划设计各种类型的结构，包括桥梁，大坝，发电厂，设备支撑，海面上的特殊结构，美国太空计划，发射塔，庞大的天文和无线电望远镜，以及许多其他种类的项目。结构工程师应用计算机确定一个结构必须承受的力：自重，风荷载和飓风荷载，建筑材料温度变化引起的胀缩，以及地震荷载。他们也需确定不同种材料如钢筋，混凝土，塑料，石头，沥青，砖，铝或其他建筑材料等的复合作用。 水利工程学。土木工程师在这一领域主要处理水的物理控制方面的种种问题。他们的项目用于帮助预防洪水灾害，提供城市用水和灌溉用水，管理控制河流和水流物，维护河滩及其他滨水设施。此外，他们设计和维护海港，运河与水闸，建造大型水利大坝与小型坝，以及各种类型的围堰，帮助设计海上结构并且确定结构的位置对航行影响。 岩土工程学。专业于这个领域的土木工程师对支撑结构并影响结构行为的土壤和岩石的特性进行分析。他们计算建筑和其他结构由于自重压力可能引起的沉降，并采取措施使之减少到最小。他们也需计算并确定如何加强斜坡和填充物的稳定性以及如何保护结构免受地震和地下水的影响。 环境工程学。在这一工程学分支中，土木工程师设计，建造并监视系统以提供安全的饮用水，同时预防和控制地表和地下水资源供给的污染。他们也设计，建造并监视工程以控制甚至消除对土地和空气的污染。他们建造供水和废水处理厂，设计空气净化器和其他设备以最小化甚至消除由工业加工、焚化及其他产烟生产活动引起的空气污染。他们也采用建造特殊倾倒地点或使用有毒有害物中和剂的措施来控制有毒有害废弃物。此外，工程师还对垃圾掩埋进行设计和管理以预防其对周围环境造成污染。
第一课现代数字设计及数字信号处理 课文 A: 数字信号处理简介 1.什么是数字信号处理？ 数字信号处理，或DSP，如其名称所示，是采用数字方式对信号进行处理。在这种情况下一个信号可以代表各种不同的东西。从历史的角度来讲，信号处理起源于电子工程，信号在这里意味着在电缆或电话线或者也有可能是在无线电波中传输的电子信号。然而，更通用地说，一个信号是一个可代表任何东西--从股票价格到来自于远程传感卫星的数据的信息流。术语“digital”来源于“digit”，意思是数字（代可以用你的手指计数），因此“digital”的字面意思是“数字的，用数字表示的”，其法语是“numerique”。一个数字信号由一串数字流组成，通常（但并非一定）是二进制形式。对数字信号的处理通过数字运算来完成。 数字信号处理是一个非常有用的技术，将会形成21世纪的新的科学技术。数字信号处理已在通信、医学图像、雷达和声纳、高保真音乐产生、石油开采等很广泛的领域内引起了革命性的变革。这些领域中的每一个都使得DSP技术得到深入发展，有该领域自己的算法、数学基础，以及特殊的技术。DSP发展的广度和深度的结合使得任何个人都不可能掌握已发展出的所有的DSP技术。DSP教育包括两个任务：学习应用数字信号处理的通用原则及学习你所感兴趣的特定领域的数字信号处理技术。 2.模拟和数字信号 在很多情况下，所感兴趣的信号的初始形式是模拟电压或电流，例如由麦克风或其它转换器产生的信号。在有些情况下，例如从一个CD播放机的可读系统中输出的信号，信号本身就是数字的。在应用DSP技术之前，一个模拟信号必须转换成数字信号。例如，一个模拟电压信号，可被一个称为模数转换器或ADC的电路变换成数字信号。该转换器产生一系列二进制数字作为数字输出，其值代表每个采样时刻的输入模数转换设备的电压值。 3.信号处理 通常信号需要以各种方式处理。例如，来自于传感器的信号可能被一些没用的电子“噪声”污染。测心电图时放在病人胸部的电极能测量到当心脏及其它肌肉活动时微小的电压变化。信号也常会被来自于电源的电磁干扰所影响。采用滤波电路处理信号至少可以去掉不需要的信号部分。如今，对信号滤波以增加信号的质量或抽取重要信息的任务越来越多地由DSP技术完成而不是采用模拟电路完成。 4.DSP的发展和应用 数字信号处理的发展起源于60年代大型数字计算机进行数字处理的应用，如使用快速傅立叶变换（FFT）可以快速计算信号的频谱。这些技术在当时并没有被广泛应用，因为通常只有在大学或者其它的科研机构才有合适的计算机。 由于当时计算机很贵，DSP仅仅局限于少量的非常重要的应用。先驱们的探索工作主要集中在4个关键领域：雷达和声纳，用于保卫国家安全；石油开采，可以赚大量的钱；空间探索，其中的数据是不能重复产生的；及医学图像，可以救治生命。 20世纪80年代到90年代个人电脑的普及使得DSP产生了很多新的应用。与以往由军方或政府的需求驱动不同，DSP突然间由商业市场的需求驱动了。任何认为自己能在这个飞速发展的领域赚钱的人都会立即成为DSP供应商。DSP通过在移动电话、CD播放器及语音邮件等产品中应用进入了公共应用领域。 这些技术革命是自上而下发生的。在20世纪80年代早期，DSP是电子工程专业的研究
一、二、 十一、汉译英时分多址：TDMA （Time Division Multiple Address/ Time Division Multiple Access）2、通用无线分组业务：GPRS General Packet Radio Service 3、国际电报电话咨询委员会：CCITT 4、同步数字体系：SDH Synchronous Digital Hierarchy （同步数字序列） 5、跳频扩频：FHSS frequency hopping spread spectrum 6、同步转移模块：STM synchronous transfer module 7、综合业务数字网：ISDN Integrated Services Digital Network 8、城域网：MAN Metropolitan Area Network 9、传输控制协议/互联网协议：TCP/IP Transmission Control Protocol/Internet Protocol 10、服务质量：QOS Quality of Service 11、中继线：trunk line 12、传输速率：transmission rate 13、网络管理：network management 14、帧结构：frame structure 15、移动手机：Mobile Phone 手机 Handset 16、蜂窝交换机：（Cellular switches）（电池开关cell switch）(cell 蜂房) 17、天线：Antenna 18、微处理器：microprocessor 19、国际漫游：International roaming 20、短消息：short message 21、信噪比：SNR(Signal to Noise Ratio) 22、数字通信：Digital communication 23、系统容量：system capacity 24、蜂窝网：cell network（cellular network）（Honeycomb nets） 25、越区切换：Handover 26、互联网：internet 27、调制解调器：modem 28、频谱：spectrum 29、鼠标：Mouse 30、电子邮件：electronic mail E-mail 31、子网：subnet 32、软件无线电：software defined radios 33、网络资源：network resources 十二、英译汉 1、mobile communication：移动通信 2、Computer user：计算机用户 3、Frame format：帧格式 4、WLAN：wireless local area network 无线局域网络 5、Communication protocol：通信协议 6、Transmission quality：传输质量 7、Remote terminal：远程终端 8、International standard：国际标准 9、GSM：全球移动通信系统 Global System for Mobile Communications 10、CDMA：码分多址Code Division Multiple Access 11、ITU：国际电信联盟 International Telecommunication Union 12、PCM：pulse code modulation 脉冲编码调制 13、WDM：波分复用Wavelength Division Multiplex 14、FCC：联邦通信委员会 Federal communications commission 15、PSTN：公用电话交换网 Public Switched Telephone Network 16、NNI：网络节点借口Network Node Interface 17、WWW：万维网World Wide Web 18、VOD：视频点播Video-On-Demand 19、VLR：访问位置寄存器 Visitor Location Register 20、MSC：移动交换中心Mobile Switching Centre 21、HLR：原籍位置寄存器Home Location Register 22、VLSI：超大规模集成电路 Very Large Scale Integrated Circuits 23、Bluetooth technology：蓝牙技术 24、Matched filter：匹配滤波器 25、ADSL：非对称数字用户环路Asymmetrical Digital Subscriber Loop非对称数字用户线路(Asymmetric Digital Subscriber Line) 26、GPS：全球定位系统Global Position System 27、ATM：异步传输模式Asynchronous Transfer Mode
The General Situation of AT89C51 The AT89C51 is a low-power, high-performance CMOS 8-bit microcomputer with 4K bytes of Flash Programmable and Erasable Read Only Memory (PEROM) and 128 bytes RAM. The device is manufactured using Atmel’s high density nonvolatile memory technology and is compatible with the industry standard MCS-51?instruction set and pin out. The chip combines a versatile 8-bit CPU with Flash on a monolithic chip; the Atmel AT89C51 is a powerful microcomputer which provides a highly flexible and cost effective solution to many embedded control applications. Features: ?Compatible with MCS-51?Products ?4K Bytes of In-System Reprogrammable Flash Memory ?Endurance: 1,000 Write/Erase Cycles ?Fully Static Operation: 0 Hz to 24 MHz ?Three-Level Program Memory Lock ?128 x 8-Bit Internal RAM ?32 Programmable I/O Lines ?Two 16-Bit Timer/Counters ?Six Interrupt Sources ?Programmable Serial Channel ?Low Power Idle and Power Down Modes The AT89C51 provides the following standard features: 4K bytes of Flash, 128 bytes of RAM, 32 I/O lines, two 16-bit timer/counters, a five vector two-level interrupt architecture, a full duplex serial port, on-chip oscillator and clock circuitry. In addition, the AT89C51 is designed with static logic for operation down to zero frequency and supports two software selectable power saving modes. The Idle
中英文对照：国际工程招标说明书中英文对照：国际工程招标说明书 国际工程招标说明书 日期： 合同招标 一、中华人民共和国从世界银行申请获得贷款，用于支付＿＿＿＿＿项目的费用。部分贷款将用于支付工程建筑、＿＿＿＿等各种合同。所有依世界银行指导原则具有资格的国家，都可参加招标。 二、中国＿＿公司邀请具有资格的投标者提供密封的标书，提供完成合同工程所需的劳力、材料、设备和服务。 三、具有资格的投标者可从以下地址获得更多的信息，或参看招标文件： 中国A公司 四、每一位具有资格的投标者在交纳＿＿＿＿＿美元，并提交书面申请后，均可从上述地址获得招标文件。 五、每一份标书都要附一份投标保证书，且应不迟于＿＿＿＿＿提交给A公司。 六、所有标书将在＿＿＿＿＿当着投标者代表的面开标。 七、如果具有资格的国外投标者希望与一位中国国内的承包人组建合资公司，需在投标截止日期前30天提出要求。业主有权决定是否同意选定的国内承包人。 八、标前会议将在＿＿＿＿＿＿＿＿＿＿召开。 投标者须知 一、工程概述 二、资金来源 中华人民共和国向世界银行申请一笔贷款，用以支付＿＿＿＿＿工程。其中部分贷款将用于支付此合同工程。只有应中国政府的要求，根据贷款协议的条件，IFI才会同意付款。除中国外，任何组织不能从贷款协议中获得权利或取得贷款。 世行贷款只用于支付瑞士和与中国有商贸关系世行成员国生产的产品和提供的服务。 世行贷款不足的部分将由业主用中国政府提供的资金支付。 三、资格要求 所有根据世行的“采购指导原则”具有资格的国家均可投标。 本合同项下的一切货物、服务均应来自上述具有资格的国家。本合同项下的一切开支仅限于支付这样的货物和服务。 货物、服务来源地与投标者国籍含义不同。 为说明自己有资格中标，投标者应向业主提供所规定的证明，保证有效地执行合同。为此，业主和中国A公司在公布中标者前，可要求投标者更新其先前提供的资格证明材料。投标者提供的材料应包括：法律地位证明文件复本，注册地及主要经营场所。如果是合资公司，应提供合资者的材料。 提供主要合同执行人的资格、经历证明材料。 填写执行合同计划所需设备。 填写可能的分包人。 目前进行中涉及投标者的诉讼的情况。 建设构想细节。 投标者可更新资格证明申请，在投标日亲手交出。 由两家或两家以上公司组成的合资企业应满足以下条件： 标书和投标成功后的协议书对所有合资人都有法律约束力。 由所有合资人的授权签字人签署并提交一份委托书，提名合资人中的一个为主办人。 合资主办人被授权承担义务，代表任何一位或全体合资人接受指导。整个合同的执行，包括款项支付
Building construction concrete crack of prevention and processing Abstract The crack problem of concrete is a widespread existence but again difficult in solve of engineering actual problem, this text carried on a study analysis to a little bit familiar crack problem in the concrete engineering, and aim at concrete the circumstance put forward some prevention, processing measure. Keyword: Concrete crack prevention processing Foreword Concrete's ising 1 kind is anticipate by the freestone bone, cement, water and other mixture but formation of the in addition material of quality brittleness not and all material.Because the concrete construction transform with oneself, control etc. a series problem, harden model of in the concrete existence numerous tiny hole, spirit cave and tiny crack, is exactly because these beginning start blemish of existence just make the concrete present one some not and all the characteristic of quality.The tiny crack is a kind of harmless crack and accept concrete heavy, defend Shen and
Unit 13 Comparison between GSM and CDMA GSM与CDMA之比较 Using CDMA/FDD technology, subscribers of CDMA cellular mobile communication system can transmit their information simultaneously through the same channel. On the other hand, the GSM system adopts TDMA/FDD method to transmit and distinguish information from different GSM mobile stations. In addition, in favor of QCELP arithmetic, RAKE receiver, power control and soft switching etc., CDMA shows more advantages in its system performance than the GSM, such as greater anti-interference capability, bigger system capacity, higher successful connection ratio, fewer off-line chances, low probability of intercept(LPI), and so on. 使用码分多址/频分双工技术，用户的蜂窝移动通信系统的传输信息的同时，通过同样的渠道。另一方面，该系统采用时分多址/频分双工传输的方法和识别信息从不同的移动台。此外，有利于中国电信集团广州研发中心算术，耙式接收器，功率控制和软开关等，显示出更多的优势在码分多址系统性能比，如更高的抗干扰能力，更大的系统容量，连接成功率较高，离线的机会少，低截获概率（低截获概率），等。 1, Power Control and RAKE Receiver功率控制和瑞克接收机 When different subscribers send their information to the same BS(base station), different signal power caused by different transmitting distances will consequentially cause interference with each other, especially for those MSs(mobile station) being far away from BS will be seriously disturbed because of their almost submerged signals by signals of the close-to-BS MSs.[2] p110 In order to solve this problem and keep high system performance, power control technique is introduced in CDMA communication system, which can effectively overcome this cross-disturbance. As one of the core techniques in CDMA cellular mobile communication system, power control can make the signal power from all subscribers to the BS equivalent through adjusting the transmitting power from each subscriber. 为解决这一问题，保持较高的系统性能，功率控制技术介绍了码分多址通信系统，它可以有效地克服这cross-disturbance。作为一个核心技术在蜂窝移动通信系统的功率控制，可以使信号功率从所有用户的学士学位相当于通过调整发射功率，从每个用户。 Power control can be not only divided to open-loop control and closed-loop control, but also to forward (down) power control and backward (up) power control. For open-loop control method, subscriber adjusts emitting power according to the measured frame error probability, while for the closed-loop power control, base station measures the signal-to-noise ratio of received signals and then adjust the transmitting power of corresponding MS. 功率控制不仅可以分为开环控制和闭环控制，而且还提出了（下）功率控制和反向功率控制（上）。开环控制方法，用户调整发射功率根据测量帧错误概率，同时为闭环功率控制，基站测量接收信号的信噪比，然后调整发射功率相应的女士 The backward power control in CDMA system can be divided into two kinds of control technique, the open-loop backward power control only used by mobile station, and the closed-loop
通信工程专业英语翻译 JXTA is a crystallization by Sun company's chief scientist Bill Joy's more than twenty years of brewing."JXTA technology is a platform for Network programming and calculation.To solve the modern distribution calculation especially peer-to-peer (Peer to Peer, P2P) in the calculation of the problem".[1] JXTA research project,which will provide a new framework that make the user more convenient to access to connect on the Internet's personal computer resources, thus further expand Internet 's space. At the same time JXTA is also the Sun's "ONE Internet" strategic continuance, and will take a more positive attitude to compete with the .net strategy of Microsoft and Hailstorm plan . JXTA agreement defines a set of six agreement based on XML, the organization of node into node group, release and found some resources, communication and mutual monitoring provides standardized method.(Endpoint Routing Protocol,ERP) is used for node found routing.To send a message to other nodes, and through the potential firewall and connection.(Rendezvous Protocol,RVP) s used for the nodes in the group to spread information.(Peer Resolver Protocol,PRP) is Used to one or more points to send general inquiries, and receive the response of inquiries.
兰州交通大学 学期论文 中文题目建筑市场及其发展 英文题目Construction Market and its Development 专业通信工程 姓名徐宏 学号201210048 指导教师刘虹 提交日期December.24 兰州交通大学
学期论文评语
摘要 随着市场经济快速的发展，作为领军行业的工程建筑行业发展势头迅猛，并成为我国市场经济发展中的领军行业，带动我国市场经济的发展。 自从改革开放以来，我国建筑业得到了很大的发展，其产值在国民生产总值中的比重逐年增加，它的发展带动了一大批相关产业，如钢铁、建材、化工、家电等上下游产业的迅猛发展。从发达工业化国家建筑业发展的规律来看，我国正处在农业国逐步转变为工业化国家的历史阶段。在这个较长的历史发展阶段，建筑市场潜力巨大，建筑业具有广阔的发展前景。建筑业作为国有经济的重要的物质生产部门，将随着我国工业化进程的加快，而进入长期稳定发展的时期。本论文通过对建筑市场及其发展的介绍，让我们进一步了解我国建筑行业的发展。 本论文由五部分组成。第一章，简介建筑市场及其分类方式。第二章，从广义和狭义两个方面来简述建筑市场的概念。第三章，说明建筑市场的主体，包括业主，承包商，中介机构三方面。第四章，介绍建筑市场的客体，也就是建筑产品。第五章，结论部分，介绍我国建筑市场现状及其发展趋势。 关键词：建筑行业建筑市场现状发展
Abstract With the rapid development of market economy, construction industry as the leading industry is developing rapidly, and become China's market economy development in the leading industry, promote the development of market economy in china. ○1“Since the reform and opening up, China's construction industry has been greatly developed, the proportion of its output value in GDP has increased year by year, which led to the development of a large number of related industries, such as the rapid development of iron and steel, building materials, chemical, home appliances and other downstream industries.”From the view of development of construction industry of developed industrial countries, China is in an agricultural country gradually into the historical stage of industrialized countries. In the long historical development stage, the construction market has great potential, the construction industry has a broad development prospect. The construction industry as a state-owned economy the important material production sector, along with the acceleration of China's industrialization, and enter a long-term stable development period. In this paper, through the construction market and its development is introduced, let us further understand the development of the construction industry in our country. This thesis consists of five parts. The first chapter, introduction of the construction market and its classification. The second chapter, from the broad sense and narrow sense concept of two aspects of the construction market. The third chapter, the main body, the construction market include the owner, contractor, agencies from three aspects. The fourth chapter introduces the architecture, object market, also is the building products. The fifth chapter, the conclusion part, introduces the status quo of China's construction market and its development trend. Keywords: Construction industry Construction market The present situation Development