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雷电感应电压matlab
matlab雷电过电压。该程序是在计算电力系统输电线路上由于雷电冲击在避雷线上而在其他三相上产生的雷电过电压程序
- 2020-12-02下载
- 积分：1
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NACA翼型生成软件
自动生成NACA翼型数据点，为后续画网格，做流体仿真做准备！
- 2020-07-02下载
- 积分：1
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电力系统自动化课程设计
电网频率是衡量电能质量的主要指标，对保持电力系统稳定安全运行具有重要意义，作为自动发电控制(automatic generation control，AGC)基本目的之一的负荷频率控制(load frequency control，LFC)是实现电网频率稳定的重要手段[1]，其通过调节系统中发电机有功功率输出以保持互联电网区域间联络线交换功率和频率偏移在给定范围内。自从Kirchmayer[2]提出该问题以来，广大研究人员也先后提出了许多设计控制方法来解决LFC 问题，如滑模技术、鲁棒控制、人工神经网路、遗传算法、粒子群算法、预测控制等。由于水轮发电系统是一个非最小相位系统，要把这些计算量大且
- 2020-11-29下载
- 积分：1
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基于MATLAB/Simulink 的双电机伺服控制系统仿真模型
设计通过位置调节器 APR(Automatic position regulator)、 转速调节器ASR(Automatic speed regulator)、电流调节器 ACR(Automatic current regulator)构成三闭环位置伺服控制系统， 来控制直流电机。实现两台电机（电机 x， 电机 y） 位置联动， 在二维平面工作台上实现准确位置跟随。 利用 MATLAB/Simulink 软件建立了双电机伺服控制系统仿真模型。
- 2021-05-06下载
- 积分：1
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HS8546V 华为光猫Shell补全补丁
这个补丁可以补全shell。需要web界面打开LAN侧的telnet，打开tftp服务器，然后登陆telnet，在WAP提示符load pack by tftp svrip 192.168.1.2 remotefile hs8546v_shell_spbin。更具体步骤在此不做说明。
- 2020-12-06下载
- 积分：1
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Vehicle Dynamics Theory and Application
不错的汽车动力学教材，是参与汽车底盘电子开发的动力学基础。Reza n. jazarVehicle DynamicsTheory and ApplicationsSpringerReza n. jazarDept of Mechanical EngineeringManhattan collegeRiverdale. NY 10471ISBN:978-0-387-74243-4e-ISBN:978-0-387-74244-1Library of Congress Control Number: 200794219c 2008 Springer Science+ Business Media, LLCAll rights reserved. This work may not be translated or copied in whole or in part without thewritten permission of the publisher(Springer Science+Business Media, LLC, 233 SpringStreet, New York, NY 10013, USA), except for brief excerpts in connection with reviews orscholarly analysis. Use in connection with any form of information storage and retrievalelectronic adaptation, computer software, or by similar or dissimilar methodology now knownor hereafter developed is forbidden. The use in this publication of trade names, trademarksservice marks and similar terms, even if they are not identified as such, is not to be taken as anexpression of opinion as to whether or not they are subject to proprietary rightsPrinted on acid-free paper987654321springer. comKavoshmy daughter, Vazan,and my wife, MojganHappiness is when you win a race against yourselfPrefaceThis text is for engineering students. It introduces the fundamental knowledge used in vehicle dymamics. This knowledge can be utilized to developcomputer programs for analyzing the ride, handling, and optimization ofroad vehiclesVehicle dynamics has been in the engineering curriculum for more thana hundred years. Books on the subject are available, but most of themare written for specialists and are not suitable for a classroom applicationA new student, engineer, or researcher would not know where and howto start learning vehicle dynamics. So, there is a need for a textbook forbeginners. This textbook presents the fundamentals with a perspective onfuture trendsThe study of classical vehicle dynamics has its roots in the work ofgreat scientists of the past four centuries and creative engineers in thepast century who established the methodology of dynamic systems. Thedevelopment of vehicle dynamics has moved toward modeling, analysisand optimization of multi-body dynamics supported by some compliantmembers. Therefore, merging dynamics with optimization theory was anexpected development. The fast-growing capability of accurate positioninsensing, and calculations, along with intelligent computer programming arethe other important developments in vehicle dynamics. So, a textbook helpthe reader to make a computer model of vehicles, which this book doesLevel of the bookThis book has evolved from nearly a decade of research in nonlineardynamic systems and teaching courses in vehicle dynamics. It is addressedprimarily to the last year of undergraduate study and the first year graduatestudent in engineering. Hence, it is an intermediate textbook. It providesboth fundamental and advanced topics. The whole book can be coveredin two successive courses, however, it is possible to jump over some sections and cover the book in one course. Students are required to know thefundamentals of kinematics and dynamics, as well as a basic knowledge ofnumerical methodsThe contents of the book have been kept at a fairly theoretical-practicallevel. Many concepts are deeply explained and their application empha-sized, and most of the related theories and formal proofs have been explained. The book places a strong emphasis on the physical meaning andapplications of the concepts. Topics that have been selected are of highinterest in the field. An attempt has been made to expose students to aPrefacebroad range of topics and approachese There are four special chapters that are indirectly related to vehicle dy-amics: Applied Kinematics, Applied Mechanisms, Applied dynamics, andApplied vibrations. These chapters provide the related background to understand vehicle dynamics and its subsystemsOrganization of the bookThe text is organized so it can be used for teaching or for self-studyChapter 1"Fundamentals, "contains general preliminaries about tire andrim with a brief review of road vehicle classificationsPart I"One Dimensional Vehicle Dynamics, " presents forward vehicledynamics, tire dynamics, and driveline dynamics. Forward dynamics refersto weight transfer, accelerating braking, engine performance, and gear ratiodesignPart II"Vehicle Kinematics, presents a detailed discussion of vehiclemechanical subsystems such as steering and suspensionsPart IIT"Vehicle Dynamics, employs Newton and Lagrange methodsto develop the maneuvering dynamics of vehiclesPart Iv "Vehicle Vibrations, presents a detailed discussion of vehi-cle vibrations. An attempt is made to review the basic approaches anddemonstrate how a vehicle can be modeled as a vibrating multiple degreeof-freedom system. The concepts of the Newton-Euler dynamics and La-grangian method are used equally for derivation of equations of motionThe RMS optimization technique for suspension design of vehicles is intro-duced and applied to vehicle suspensions. The outcome of the optimizationtechnique is the optimal stiffness and damping for a car or suspended equipmentMethod of presentationThis book uses a fact-reason-application"structure. The "fact"is themain subject we introduce in each section. Then the reason is given as a" proof. The application of the fact is examined in some examples. Theexamplesare a very important part of the book because they show howto implement the facts. They also cover some other facts that are neededto expand the subjectPrerequisitesSince the book is written for senior undergraduate and first-year graduatelevel students of engineering, the assumption is that users are familiar withmatrix algebra as well as basic dynamics. Prerequisites are the fundamentals of kinematics, dynamics, vector analysis, and matrix theory. Thesebasics are usually taught in the first three undergraduate yearsPrefaceUnit SystemThe system of units adopted in this book is, unless otherwise stated, theinternational system of units(SI). The units of degree(deg)or radian(rad)are utilized for variables representing angular quantitiesSymbolse Lowercase bold letters indicate a vector. Vectors may be expressed inan n dimensional Euclidian space. ExamplerCUppercase bold letters indicate a dynamic vector or a dynamic matrix, such as force and moment. ExampleFo Lowercase letters with a hat indicate a unit vector. Unit vectors arenot bolded. ExampleLowercase letters with a tilde indicate a 3 x 3 skew symmetric matrixassociated to a vector. Examplea3211An arrow above two uppercase letters indicates the start and endpoints of a position vector. ExampleON = a position vector from point o to point Ne The length of a vector is indicated by a non-bold lowercase letterExampleCapital letter B is utilized to denote a body coordinate frame. ExampleB(ocgB(Oxyz)B1(o1x19121)ⅹ11PrefaceCapital letter G is utilized to denote a global, inertial, or fixed coordinate frame. ExampleG(XYZG(OXYZRight subscript on a transformation matrix indicates the departureframes. ExampleRB= transformation matrix from frame B(oxyz)Left superscript on a transformation matrix indicates the destinationframe. ExampleRBtransformation matrix from frame B(o cgz)to frame G(OxYZ)Capital letter R indicates rotation or a transformation matrix, if itshows the beginning and destination coordinate frames. Example0BSIn a0Whenever there is no sub or superscript, the matrices are shown in abracket. ExampleCOS asin a osIn aCOs O0e Left superscript on a vector denotes the frame in which the vectoris expressed. That superscript indicates the frame that the vectorbelongs to; so the vector is expressed using the unit vectors of thatEr= position vector expressed in frame G(OXYZ)Right subscript on a vector denotes the tip point that the vector isreferred to. ExamplePsition vector ofexpressed in coordinate frame G(OXYZ)Right subscript on an angular velocity vector indicates the frame thatthe angular vector is referred to. ExampleB= angularof the body coordinate frame B(oxyz)
- 2020-12-12下载
- 积分：1
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多进制LDPC码改进算法研究
对多进制LDPC码的构造、译码、码长及码率等方面进行仿真研究，以期为多进制LDPC码的实用化发展提供设计参考。76科技论坛如图1建立了多进制LDPC码的仿真平台,主要对多进制LD-时,对多进制LDPC码的译码算法复杂度进行计算。经仿真分析和PC码构造方法、译码算法、不同码长和不同码率进行了仿真对比。计算,基于3种算法的多进制IDPC码在高码率时均具有逞近香农系统运用高斯编码,信道是高斯白噪声信道,调整方式釆用BPSK限的特性。Ig-FF-BP译码算法的计算复杂度低于FTBP和调制,最大迭代次数为30,并且i-PG随机构造方法构造的非规BP算法,虽然BP算法表现出更好的系统性能但前者更适合于硬则LDPC码的变量节点度分布服从4(x)-038354x+0023x2+0.574092。件实现。这对多进制LDPC码的实用化有较大意义,并且对有关多表1给出了用于仿貞实验的多进制IDPC码参数,他们均为八元域进制IDC码译码算法的应用领域也有重婆的参考意义。码型且校验矩阵H的列重为4。现在对多进制LDPC码的编译码整参考文献体系统中能够对码字纠错效果产生影响的参数分别进行性能仿真。[] Gallager R.G.L灬 w Density Parity Check Codes. IRE Transac-3仿真结果tions on Information Theory 1962, 8: 208-220图2分别给出了LDPC-Ⅰ按照 Mackay、r-FS、 rg-PEG、ir-PE、[2] MacKay D.J.C. and ncal r.m. Ncar Shannon limit performanccir-QC构造方法基丁Lg-FFT-B译码算法得到的八进制LDPC码 of low- density parity- -check codes. Electronics Letters,199,32:在不同信噪比条件下的误码率曲线。由图可以看出,随着信噪比的1645-1646增加,五种码的性能开始出现差异。ir-PEC构造方法的误码率性能「3] MACKAY D, W ISON S, DAY Y M.Corconstruc明显优于其它几种构造方法,在2dB的信噪比时,误码性能接近 tions of irregular Gallager codes[J. I Transaction on Communica106数量级。其次为ir-QC、rg-PEG、rg-PS,可以看出i-QC对比于tion,199,47(10:1449-1454ir-PEG构造方法,在2dB时有10数量级的误码率性能损失。并且[4]MC. Davey and D JC. Mac Kay. Low density parity check codesrg-PEG、rg-PS两种构造方法在低信噪比下误码率性能比较接近, over GF(q) J. IEEE Communication Letter,1998,2(6):165-167但其性能明显差于ir-QC构造方法。 Mackay构造方法性能最差,当[5jLan,YY.rai, L Chen,S.Lin,andK, Abdel- Ghaffar. a trellis信噪比大于2B时,已经呈蚬差错平底效应的趋势。由图可以看出 based method for removing cycles from bipartite graphs and corir-PEG构造方法的随机性好于ir-QC结构化构造算法码字伫能, struction of low density parity check codes[ J]. IEEE Communicarg-PEG构造方法的随机性也好于rg-PS结构化构造算法码字性 tion letters,2004,8(7):443-45能,这说明非规则随机构造算法的码字性能优于随机构造算法构造[6JmXu, Lei cher, Ivana Djurdjevic, Shu lin, and Khaled ah的码字性能;对应随机构造算法构造的码字性能优于结构构造算法dl- Chaffer. Construction of Regular and Irregular LDPC Codes:构造的码字性能。因此选用ir-PEG构造方法来构造校验矩阵。 Geometry Decomposition and Masking[. iEeE Transactions orl图3分别给出了LDPC-1采用i-PG构造方法基于 Information Theory,2007,53(1:121-134Log-FFT-BP、FT-BP和BP译码算法得到的八进制LDPC码在不[7] David J C. MacKay. ood Error Correcting Codes Based on同信噪比情况下的误码率血线。从图对比可看岀,随着信噪比的增 very Sparse. EEE Transaction on Information Theory,19加BP译码算法的性能优于Iog-FT-BP和FFT-BP译码算法,而(2:399-431Log-FFT-BP和上I-BP两种译码算法在相同的伽罗华域和高信噪[8 DAVEY MC. Error correction using low density parity check比下,误码率性能没有很大的差异。同时,Log-FFT-BP的译码性能 codes. Cambridge,U.K.Uniw. Cambridge,199在2B的信噪比时,误码性能接近⑩05数量级,已满足大部分通信⑨9 Wymeersch F., Steendam H and Moeneclaey M.Iog- domain要求。decoding of LDPC codes over GF(q IC). IEEE International Con-图4分别给出了使用i-PEG构造方法相同码率不同码长基于 ference on Communications,2004:772-775多进制Lg-FI-BP译码算法得到的八进制LDPC码在低信噪比情况下的误码率曲线。由图可得出,由于传输码字长度变大,多进制LDPC码的性能随之有着显著的提高由此可知多进制LDPC码的传输码字长度变长的话,其误码纠错性能会较短码更好。这是因为码字长度的增大,使得稀疏矩阵里非零元素所占据的百分比在对应减少,进而 anner图所看到的坏长在增大,纠错性能就变的更加好。从码长度来考志,码长度为1536时,误码率曲线基于GF8在信噪比为2dB时接近106数量级,首先考虑性能问题,基于满足大部分通信要求。其次考虑码长增长,会给系统编译码带来很高的复杂度,这对实际系统来说是很严峻的问题,最后考虑硬件系统在实际仿真测试中带来性能损失,需要软件仿真来留出至少1个数量级弹性变化范围,最终确定选取码长度1536为多进制IDPC码为系统码长图5分别给出了使用ir-PEG构造方法相同码长不同码率基于多进制Iog-FFT-BP译码算法得到的八进制IDC码在低信噪比情况下的误码率曲线从图中都可以看出,在码长相同的条件下,码率越低,多进制IDC码的性能越好,但是码率越低,信息的传输速率也随之下降,则导致系统的频带利用率越低。反之,随着码率的增大,系统的误码率性能随之下降。这是因为码率越高,参加校验的校验比特越少,也就是信道编码增加的冗余度越小,系统的可靠性也随之降低。由于在码长相同的情况下,码率12性能与其他码率相比有较好的性能,所以系统方案最终选取码率1/2的多进制LDPC码。结束语本文对多进制LDPC码的编译码整体系统中能够对码字纠错效果产生影响的参数分别进行验证,运用统变量的原则分别对校验矩阵构造算法,译码算法,码长和码率等参数进行仿真对比。同
- 2020-11-27下载
- 积分：1
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opencv中文参考手册chm
opencv中文参考手册chm
中文手册 介绍很详细 分类很清晰
- 2021-08-24 00:31:08下载
- 积分：1
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瑞萨的can的资料CAN的入门书。做的很好的资料
瑞萨的can的资料CAN的入门书，很好的学习资料，RENESAS应用手册是什么?是的缩写(以下称为),是国际标准化的串行通信协议。在当前的汽车产业中,出于对安全性、舒适性、方便性、低公害、低成本的要求,各种各样的电子控制系统被开发了出来。巾于这些系统之间通信所用的数据类型及对可靠性的要求不尽相同,巾多条总线构成的情况很多,线束的数量也随之增加。为适应“诚少线束的数量”、“通过多个,进行大量数据的高速通信”的需要牛德国电气商博世公司开发出面向汽车的通信协议。此后,通过及行了标准化,现在在欢洲已是汽车网络的标准协议。现在,的高性能和可靠性已被认同,并被广泛地应用于工业自动化、船舶、医疗设备、工业设备等方面。图是车载网终的构想示意图。等通信协议的开发,使多种通过网关进行数据交换得以实现。马达马达。。马达开关开关。安全画乘客检测空调子网车门雷达且且且子网白线检测伙表级遥控车身部自逗应引爆管巡航前大灯窗电动组合灯网关囊控制发动机胎压部信息部MCcD音视频父通信电子防发动机转向制动子网碟盒息导航盗系统动变底盘部故障诊断部(规格)诊断工具图车载网络构想注】国际标准化组织为戴姆勒克莱斯勒公司注册商标。RENESAS应用手册的应用示例图为的应用示例图的应用示例ENESAS应用手册总线拓扑图控制器根据两根线上的电位差来判断总线电平。总线电平分为显性电平和隐性电平,者必居其一。发送方通过使总线电平发生变化,将消息发送给接收方。图是的连接小意图收发器收发器连接图R∈NEs∧s应用手册的特点协议只有以下特点多主控制在总线空闲吋,所有的单元都可开始发送消息(多主控制)最先访问总线的单元可获得发送权(方式)。多个单元同时开始发送时,发送高优先级消息的单元可获得发送权。消息的发送在协议中,所有的消息都以固定的柊式发送。总线空闲时,所有与总线相连的单元都可以开始发送新消息。两个以上的单元同时开始发送消息时,根据标识符(以下称为)决定优先级。并不是表示发送的目的地址,而是表示访问总线的消息的优先级。两个以上的单元同时开始发送消息时,对各消息的每个位进行逐个仲裁比较。仲裁获胜(被判定为优先级最扃)的单元可继续发送消息,仲裁失利的单元则立刻停止发送而进行接收工作。系统的柔软性与总线相连的单元没有类似于“地址”的信息。因此在总线上增加单元时,连接在总线上的其它单元的软硬件及应用层都不需要改变通信速度根据整个网络的规模,可设定适合的通信速度。在同一网络中,所冇单元必须改定成统一的通信速度。即使有一个单元的通信速度与其它的不一样,此单元也会输岀错误信号,妨碍整个网络的通信。不同网终间则可以有不同的通信速度。远程数据请求可通过发送“遥控帧”请求其他单元发送数据。错误检测功能·错误通知功能·错误恢复功能所有的单元都可以检测错误(错误检测功能)。检测出错误的单元会立即同时通知其他所有单元(错误通知功能)正在发送消息的单元一旦检测出错误,会强制结東当前的发送。强制结束发送的单元会不断反复地重新发送此消息直到成功发送为止(错误恢复功能)。故障封闭可以判断出错误的类型是总线上暂时的数据错误(如外部噪声等)还是持续的效据错误(如单元内部改障、驱动器故障、断线等)。由此功能,当总线上发生持续数据错误时,可将引起此故障的单元从总线上隔离出去。连接总线是可同时连接多个单元的总线。可连接的单元总数理论上是没有限制的。但实际上可连接的单元数受总线上的吋间延迟及电气负载的限制。降低通信速度,可连接的单元数增加;提扃通信速度,则可连接的单元数减少。【注】R∈NEs∧s应用手册错误错误状态的种类单元始终处于种状态之一。主动错误状态动错误状态是可以正常参加总线通信的状态处于主动错误状态的单元检测出错误时,输出主动错误标志被动错误状态被动错误状态是易引起错误的状态。处于被动错误状态的单元虽能参加总线通信,但为不妨碍其它单元邇信,接收时不能秋极地发送错误通知。处于被动错误状态的单元即使检测出错误,而貫它处于主动错误状态的单元如果没发现错误,整个总线也被认为是没有错误的处于被动错误状态的单元检测出错误时,输出被动错误标志。另外,处于被动错误状态的单元在发送结束后不能马上再次开始发送。在开始下次发送前,在间隔帧期间内凶须插入“延迟传送个位的隐性位总线关闭态总线关闭态是不能参加总线上通信的状态信息的接收和发送均被禁止。这些状态依靠发送错误计数和接收错误计数来管理,根据计数值决定进入何种状态。错误状态和计数值的关系如表及图所小。表错误状态和计数值单元错误状态发送错误计数值()接收错误计数值()主动错误状态被动错误状态且或总线关闭态ENESAS应用手册初始状态主动错误状态或在总线上检测到次连续的个位的隐性位被动错误状态总线关闭态发送错误计数值接收错误计数值图单元的错误状态R∈NEs∧s应用手册错误计数值发送错误计数值和接收错误计数值根据一定的条件发生变化。错误计数值的变动条件如表所示。一次数据的接收和发送可能同时满足多个条件错误计数器在错误标志的第一个位出现的时间点上开始计数。表错误计数值的变动条件接受和发送错误计数值的变动条件发送错误计数值接收错误计数值接收单元检测出错误时例外:接收单元在发送错误标志或过载标志中检测出“位错误”时,接收错误计数值不增加接收单元在发送完错误标志后检测到的第一个位为显性电平时。发送单元在输出错误标志时发送单元在发送主动错误标志或过载标志时,检测出位错误接收单元在发送主动错误标志或过载标志时,检测出位错误各单元从主动错误标志、过载标志的最开始检测出连续发送时接收时个位的显性位时之后,每检测出连续的个位的显性位时。检测岀在被动错误标志后追加的连续个位的显性位时。发送时接收时发送单元正常发送数据结束时(返回且到帧结束也未检测出错误时)。时±接收单元正常接收数据结束时(到未检测出错误且正时常返回时)时设处于总线关闭态的单元,检测到连续个位的隐性位。R∈NEs∧s应用手册协议的基本概念协议如表所示涵盖了规定的基本参照模型中的传输层、数据链路层及物理层协议中关于基本参照模型中的传输层、数据链路层及物理层,具体有哪些定义如图所示。表基本参照模型基本参照模型各层定义的主要项目层:应用层由实际应用程序提供可利用的服务。层:表示层进行数据表现形式的转换。如:文字设定、数据压缩、加密等的控制指层:会话层为建立会话式的通信,控制数据正确地接收和发送。探层:传输层控制数据传输的顺序、传送错误的恢复等,保证通信的品质。如:错误修正、再传输控制。层:网络层进行数据传送的路由选择或中继如:单元间的数据交换、地址管理。层:数据链路层将物理层收到的信号(位序列)组成有意义的数据,提供传输错误控制等数据传输控制流程。如:访问的方法、数据的形式通信方式、连接控制方式、同步方式、检错方式一共应答方式、通信方式、包(帧)的构成。位的调制方式(包括位时序条件)。层:物理层规定了通信时使用的电缆、连接器等的媒体、电气信号规格等,以实现设备间的信号传送。如:信号电平、收发器、电缆、连接器等的形态【注】(开放式系统间互联)
- 2020-12-10下载
- 积分：1
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低压开关柜cad电气图
低压开关柜cad电气图(包含电器柜制作、电气一、二次回路)
- 2021-05-06下载
- 积分：1
