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用极零点法分析线性网络
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作者 凌树涛 《杭州教育学院学报》 CAS 1997年第6期117-121,共5页
用极零点分析,它将清楚地表明线性网络的传输功能,确实是一个有效的方法.
关键词 拉普拉斯变换 极零点 线性网络分析
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戴维南定理在含受控源网络中的应用 被引量:1
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作者 夏全福 徐茜 《电工技术》 1998年第1期57-59,共3页
本文讨论了满足存在性和唯一性解的含受控源线性网络中戴维南定理的应用。从受控源的性质出发,对一种简便得到戴维南等效电路的方法及其普遍性进行了较深入的探讨。
关键词 线性网络分析 受控源 网络分析 戴维南定理
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戴维南定理对含受控源电路的新分析法 被引量:1
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作者 贺汉平 汤放奇 《株洲工学院学报》 2000年第4期29-30,46,共3页
讨论了当线性有源二端网络中含有受控源 ,且控制量在外部电路时 ,仍然可以应用戴维南定理或诺顿定理分析 ,从而扩展了戴维南定理和诺顿定理的应用。
关键词 戴维南定理 含受控源电路 线性网络分析
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卷积积分的几种计算方法归纳 被引量:2
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作者 余玲玲 《电气电子教学学报》 1994年第2期45-48,共4页
卷积积分在《信号与系统》课的时域分析中是一个很重要的概念和数学工具。除了卷积的图解法和数值解以外,直接根据卷积定义的函数式求积分也可以采用几种不同的方法来进行,本文作了归纳,意在为对此内容有兴趣的读者提供一点参考。
关键词 卷积积分 计算方法 卷积方法 《信号与系统》 数值解 时域分析 阶跃信号 图解法 线性网络分析 求积分
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简论支路电流法的普遍性
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作者 王毅 《淮北煤师院学报(自然科学版)》 1989年第4期52-53,70,共3页
关于支路电流法的普遍性问题,一般电工学中未作严格论证.本文引用网络拓扑学中几个基本概念,简要论证了这个结论,以利于认识上的完整性与科学性.
关键词 电网 线性网络分析 支路电流法
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Wavelet neural network based fault diagnosis in nonlinear analog circuits 被引量:16
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作者 Yin Shirong Chen Guangju Xie Yongle 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2006年第3期521-526,共6页
The theories of diagnosing nonlinear analog circuits by means of the transient response testing are studled. Wavelet analysis is made to extract the transient response signature of nonlinear circuits and compress the ... The theories of diagnosing nonlinear analog circuits by means of the transient response testing are studled. Wavelet analysis is made to extract the transient response signature of nonlinear circuits and compress the signature dada. The best wavelet function is selected based on the between-category total scatter of signature. The fault dictionary of nonlinear circuits is constructed based on improved back-propagation(BP) neural network. Experimental results demonstrate that the method proposed has high diagnostic sensitivity and fast fault identification and deducibility. 展开更多
关键词 fault diagnosis nonlinear analog circuits wavelet analysis neural networks.
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Drainage Network and Lineament Analysis:An Approach for Potwar Plateau(Northern Pakistan) 被引量:2
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作者 Faisal SHAHZAD Syed Amer MAHMOOD Richard GLOAGUEN 《Journal of Mountain Science》 SCIE CSCD 2009年第1期14-24,共11页
Drainage responds rapidly to tectonic changes and thus it is a potential parameter for teetonogeomorphological analysis. Drainage network of Potwar is a good geological record of movement, displacements, regional upli... Drainage responds rapidly to tectonic changes and thus it is a potential parameter for teetonogeomorphological analysis. Drainage network of Potwar is a good geological record of movement, displacements, regional uplifts and erosion of the tectonic units. This study focuses on utilizing drainage network extracted from Shuttle Radar Digital Elevation Data (SRTM-DEM) in order to constrain the structure of the Potwar Plateau. SWAN syncline divides Potwar into northern Potwar deformed zone (NPDZ) and southern Potwar platform zone (SPPZ). We extracted the drainage network from DEM and analyzed 112 streams using stream power law. Spatial distribution of concavity and steepness indices were used to prepare uplift rate map for the area. DEM was further utilized to extract lineaments to study the mutual relationship between lineaments and drainage patterns. We compared the local correlation between the extracted lineaments and drainage network of the area that gives us quantitative information and shows promising prospects. The streams in the NPDZ indicate high steepness values as compared to the streams in the SPPZ. The spatial distribution of geomorphic parameters distinctive deformation and uplift rates suggest the among eastern, central and western parts. The local correlation between drainage network and lineaments from DEM is strongly positive in the area within I km of radius. 展开更多
关键词 Drainage network LINEAMENTS streamprofile analysis uplift rate local correlation
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Tree-Based Proactive Routing Protocol for Wireless Mesh Network 被引量:2
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作者 Ji Wenjiang Ma Jianfeng +1 位作者 Ma Zhuo Ran Youliang 《China Communications》 SCIE CSCD 2012年第1期25-33,共9页
Wireless Mesh Network (WMN) is seen as an effective Intemet access solution for dynamic wireless applications. For the low mobility of mesh routers in WMN, the backbone topography can be effectively maintained by pr... Wireless Mesh Network (WMN) is seen as an effective Intemet access solution for dynamic wireless applications. For the low mobility of mesh routers in WMN, the backbone topography can be effectively maintained by proactive routing protocol. Pre-proposals like Tree Based Routing (TBR) protocol and Root Driven Routing (RDR) protocol are so centralized that they make the gateway becorre a bottleneck which severely restricts the network performance. We proposed an Optimized Tree-based Routing (OTR) protocol that logically separated the proactive tree into pieces. Route is partly computed by the branches instead of root. We also discussed the operation of multipie Intemet gateways which is a main issue in WMN. The new proposal lightens the load in root, reduces the overhead and improves the throughput. Numerical analysis and simulation results confirm that the perforrmnce of WMN is improved and OTR is more suitable for large scale WMN. 展开更多
关键词 wireless mesh network 802. lls routing protocol tree-based routing
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Convergence Analysis and Its Application in the Fixed Point Formulation of Medium Access in Wireless Network
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作者 周安福 刘敏 焦学武 《China Communications》 SCIE CSCD 2011年第1期43-49,共7页
In the Internet of things, it is of critical importance to fully utilize the potential capacity of the network with efficient medium access control (MAC) mechanisms. In this paper, we study the convergence property ... In the Internet of things, it is of critical importance to fully utilize the potential capacity of the network with efficient medium access control (MAC) mechanisms. In this paper, we study the convergence property of the fixed point formulation of distributed coordination function (DCF), which is widely used for medium access control in wireless networks. We first Kind that the fixed point could be repelling, which means that it is impossible for an MAC system to converge at its fixed point. Next, we show the existence of periodic points to prove that the fixed point function will oscillate between two periodic points when the fixed point is repelling. We also find that the average of the two periodic points is a close approximation of the fixed point. Based on the findings, we propose an algorithm to compute the fixed point efficiently. Simulation results verify the accuracy and efficiency of our algorithm compared with the previous fixed point computing method. 展开更多
关键词 resource allocation in wireless networks DCF fixed point formulation convergence property
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Quality of Service Improvement for High-Speed Railway Communications 被引量:1
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作者 ZHOU Yuzhe AI Bo 《China Communications》 SCIE CSCD 2014年第11期156-167,共12页
With the fast development of highspeed railways,a call for fulfilling the notion of communication at "anytime,anywhere" for high-speed train passengers in the Train Operating Control System is on the way.In ... With the fast development of highspeed railways,a call for fulfilling the notion of communication at "anytime,anywhere" for high-speed train passengers in the Train Operating Control System is on the way.In order to make a realization of that,new railway wireless communication networks are needed.The most promising one is the Long Term Evolution for Railway which will provide broadband access,fast handover,and reliable communication for high mobility users.However,with the increase of speed,the system is subjected to high bit error rate,Doppler frequency shift and handover failure just like other system does.This paper is trying to solve these problems by employing MIMO technique.Specifically,the goal is to provide higher data rate,higher reliability,less delay,and other relative quality of services for passengers.MIMO performance analysis,resource allocation,and access control for handover and various services in a two-hop model are proposed in this paper.Analytical results and simulation results show that the proposed model and schemes perform well in improving the system performances. 展开更多
关键词 high-speed railway QOS M1MO HANDOVER access control
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A NOVEL CALL ADMISSION CONTROL SCHEME IN CELLULAR/WLAN INTEGRATION AND PERFORMANCE ANALYSIS 被引量:1
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作者 Xia Weiwei Shen Lianfeng 《Journal of Electronics(China)》 2009年第2期168-178,共11页
In order to achieve the Quality of Service(QoS) provisioning and efficient resource utili-zation in cellular network and Wireless Local Area Network(WLAN) integration,an Integrated Ser-vice-Based Call Admission Contro... In order to achieve the Quality of Service(QoS) provisioning and efficient resource utili-zation in cellular network and Wireless Local Area Network(WLAN) integration,an Integrated Ser-vice-Based Call Admission Control(ISB-CAC) scheme is proposed in this paper.The integrated network is modeled by using multi-dimensional Markov chains.The numerical analysis is presented to evaluate the important performance measures such as the blocking probability of originating calls,the dropping probability,and the average transfer time,etc.The steady-state probabilities of the multi-dimensional Markov chains are obtained by using an iterative approach,and the CAC pa-rameters are optimally designed.The analytical model is validated by the computer simulation.It is shown that compared with the conventional WLAN-First Call Admission Control(WF-CAC) scheme,the proposed ISB-CAC scheme not only provides better QoS for mobile users but also utilizes the bandwidth resources more efficiently. 展开更多
关键词 Cellular/WLAN integration Call Admission Control(CAC) Quality of Service(QoS) Vertical handoff Markov process
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Seismic Health Monitoring of Foundations Using Artificial Neural Networks
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作者 Azlan bin Adnan Mohammadreza Vafaei 《Journal of Civil Engineering and Architecture》 2012年第6期730-737,共8页
Damage identification plays an important role in structural health monitoring systems. Despite variety in damage identification methods, little attention has been paid to the seismic damage identification of foundatio... Damage identification plays an important role in structural health monitoring systems. Despite variety in damage identification methods, little attention has been paid to the seismic damage identification of foundations. When shear walls serve as the lateral load resistance system of structures, foundations may subject to the high level of concentrated moment and shear forces. Consequently, they can experience severe damage. Since such damage is often internal and not visible, visual inspections cannot identify the location and the severity of damage. Therefore, a robust method is required for damage localization and quantification of foundations. According to the concept of performance-based seismic design of structures, the seismic behavior of foundations is considered as Force-Controlled. Therefore, for damage identification of foundation, internal forces should be estimated during ground motions. In this study, for real-time seismic damage detection of foundations, a method based on artificial neural networks was proposed. A feed-forward multilayer neural network with one hidden layer was selected to map input samples to output parameters. The lateral displacements of stories were considered as the input parameters of the neural network while moment and shear force demands at critical points of foundations were taken into account as the output parameters. In order to prepare well-distributed data sets for training the neural network, several nonlinear time history analyses were carried out. The proposed method was tested on the foundation of a five-story concrete shear wall building. The obtained results revealed that the proposed method was successfully estimated moment and shear force demands at the critical points of the foundation. 展开更多
关键词 Structural health monitoring seismic damage detection artificial neural networks performance-based design.
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