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Low-power system model for quantum entangled photon-pair source
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作者 FENG Tianxuan ZHANG Hanyi +3 位作者 FAN Rong MA Honghao DONG Mengcheng LI Lijing 《Journal of Systems Engineering and Electronics》 SCIE CSCD 2024年第5期1287-1294,共8页
The quantum entangled photon-pair source,as an essential component of optical quantum systems,holds great potential for applications such as quantum teleportation,quan-tum computing,and quantum imaging.The current wor... The quantum entangled photon-pair source,as an essential component of optical quantum systems,holds great potential for applications such as quantum teleportation,quan-tum computing,and quantum imaging.The current workhorse technique for preparing photon pairs involves performing spon-taneous parametric down conversion(SPDC)in bulk nonlinear crystals.However,the current power consumption and cost of preparing entangled photon-pair sources are relatively high,pos-ing challenges to their integration and scalability.In this paper,we propose a low-power system model for the quantum entan-gled photon-pair source based on SPDC theory and phase matching technology.This model allows us to analyze the per-formance of each module and the influence of component cha-racteristics on the overall system.In our experimental setup,we utilize a 5 mW laser diode and a typical type-II barium metabo-rate(BBO)crystal to prepare an entangled photon-pair source.The experimental results are in excellent agreement with the model,indicating a significant step towards achieving the goal of low-power and low-cost entangled photon-pair sources.This achievement not only contributes to the practical application of quantum entanglement lighting,but also paves the way for the widespread adoption of optical quantum systems in the future. 展开更多
关键词 low-power system model optical quantum system entangled photon-pair source spontaneous parametric down conversion
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Support Vector Machine-Based Nonlinear System Modeling and Control 被引量:1
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作者 张浩然 韩正之 +1 位作者 冯瑞 于志强 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2003年第3期53-58,共6页
This paper provides an introduction to a support vector machine, a new kernel-based technique introduced in statistical learning theory and structural risk minimization, then presents a modeling-control framework base... This paper provides an introduction to a support vector machine, a new kernel-based technique introduced in statistical learning theory and structural risk minimization, then presents a modeling-control framework based on SVM. At last a numerical experiment is taken to demonstrate the proposed approach's correctness and effectiveness. 展开更多
关键词 Support vector machine Statistical learning theory Nonlinear systems modeling and control.
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UML-based combat effectiveness simulation system modeling within MDE 被引量:5
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作者 ZHU Zhi LEI Yonglin +2 位作者 SARJOUGHIAN Hessam LI Xiaobo ZHU Yifan 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2018年第6期1180-1196,共17页
To reduce complexity, the combat effectiveness simulation system(CESS) is often decomposed into static structure,physical behavior, and cognitive behavior, and model abstraction is layered onto domain invariant knowle... To reduce complexity, the combat effectiveness simulation system(CESS) is often decomposed into static structure,physical behavior, and cognitive behavior, and model abstraction is layered onto domain invariant knowledge(DIK) and application variant knowledge(AVK) levels. This study concentrates on the specification of CESS’s physical behaviors at the DIK level of abstraction, and proposes a model driven framework for efficiently developing simulation models within model-driven engineering(MDE). Technically, this framework integrates the four-layer metamodeling architecture and a set of model transformation techniques with the objective of reducing model heterogeneity and enhancing model continuity. As a proof of concept, a torpedo example is illustrated to explain how physical models are developed following the proposed framework. Finally, a combat scenario is constructed to demonstrate the availability, and a further verification is shown by a reasonable agreement between simulation results and field observations. 展开更多
关键词 domain specific modeling model-driven development system engineering effectiveness simulation
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基于Modelica的发电湿汽轮机系统仿真及特性分析
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作者 王劲韬 曾国庆 +3 位作者 谢旭阳 谢罗涛 邹梓仪 陈国兵 《舰船科学技术》 北大核心 2025年第4期105-111,共7页
本文旨在解决船用发电湿汽轮机系统在使用传统模型和数字驱动方法时,数据完整性和动态仿真精度方面存在局限性的问题。在船用发电湿汽轮机物理试验平台的基础上,采用模块化建模方法,结合自顶向下的需求分析策略和自下而上的建模思想,明... 本文旨在解决船用发电湿汽轮机系统在使用传统模型和数字驱动方法时,数据完整性和动态仿真精度方面存在局限性的问题。在船用发电湿汽轮机物理试验平台的基础上,采用模块化建模方法,结合自顶向下的需求分析策略和自下而上的建模思想,明确模型的功能要求,并逐步完成各设备模块功能的调试和组合。分析结果显示,静态和变工况仿真结果的数据误差均低于5%,且在变工况下与实际机组情况基本一致。这些仿真结果能够较为真实地反映系统的运行状况,能够为后续船舶动力数字孪生系统的建立和虚实交互提供了基础。 展开更多
关键词 模块化建模 系统仿真 modelICA语言 船用发电湿汽轮机 MWorks仿真平台
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Modeling of electrode system for three-phase electric arc furnace 被引量:6
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作者 王琰 毛志忠 +2 位作者 田惠欣 李妍 袁平 《Journal of Central South University》 SCIE EI CAS 2010年第3期560-565,共6页
To simulate the process of electrode operation, a dynamic model describing the electrode system of three-phase electric arc furnace was developed. This new model can be divided into three submodels in terms of the pra... To simulate the process of electrode operation, a dynamic model describing the electrode system of three-phase electric arc furnace was developed. This new model can be divided into three submodels in terms of the practical situation. They are the power supply system model the electric arc model and the hydraulic actuator system model. According to the basic circuit theory, the power supply system model where the high voltage transmission circuit and mutual inductances were considered, was set up. The electric arc model, which was novel for the electrode control, served as the electrical load and was connected to the power supply system model. The hydraulic actuator system model consists of the proportional valve part that is modeled to capture the dead-zone nonlinear characteristics and the hydraulic cylinder part where the impact of the load force is taken into account. By comparing simulation data and actual data, the results show that the electrode system model is proved to be accurate. 展开更多
关键词 electric arc furnace electrode system model electric arc model SIMULATION
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基于24Model的动火作业事故致因文本挖掘 被引量:1
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作者 牛茂辉 李威君 +1 位作者 刘音 王璐 《中国安全科学学报》 北大核心 2025年第3期151-158,共8页
为探究工业动火作业事故的根源,提出一种基于“2-4”模型(24Model)的文本挖掘方法。首先,收集整理220篇动火作业事故报告,并作为数据集,构建基于来自变换器的双向编码器表征量(BERT)的24Model分类器,使用预训练模型训练和评估事故报告... 为探究工业动火作业事故的根源,提出一种基于“2-4”模型(24Model)的文本挖掘方法。首先,收集整理220篇动火作业事故报告,并作为数据集,构建基于来自变换器的双向编码器表征量(BERT)的24Model分类器,使用预训练模型训练和评估事故报告数据集,构建分类模型;然后,通过基于BERT的关键字提取算法(KeyBERT)和词频-逆文档频率(TF-IDF)算法的组合权重,结合24Model框架,建立动火作业事故文本关键词指标体系;最后,通过文本挖掘关键词之间的网络共现关系,分析得到事故致因之间的相互关联。结果显示,基于BERT的24Model分类器模型能够系统准确地判定动火作业事故致因类别,通过组合权重筛选得到4个层级关键词指标体系,其中安全管理体系的权重最大,结合共现网络分析得到动火作业事故的7项关键致因。 展开更多
关键词 “2-4”模型(24model) 动火作业 事故致因 文本挖掘 指标体系
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The Fuzzy Modeling Algorithm for Complex Systems Based on Stochastic Neural Network
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作者 李波 张世英 李银惠 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2002年第3期46-51,共6页
A fuzzy modeling method for complex systems is studied. The notation of general stochastic neural network (GSNN) is presented and a new modeling method is given based on the combination of the modified Takagi and Suge... A fuzzy modeling method for complex systems is studied. The notation of general stochastic neural network (GSNN) is presented and a new modeling method is given based on the combination of the modified Takagi and Sugeno's (MTS) fuzzy model and one-order GSNN. Using expectation-maximization(EM) algorithm, parameter estimation and model selection procedures are given. It avoids the shortcomings brought by other methods such as BP algorithm, when the number of parameters is large, BP algorithm is still difficult to apply directly without fine tuning and subjective tinkering. Finally, the simulated example demonstrates the effectiveness. 展开更多
关键词 Complex system modeling General stochastic neural network MTS fuzzy model Expectation-maximization algorithm
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采用STAMP-24Model的多组织事故分析 被引量:4
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作者 曾明荣 秦永莹 +2 位作者 刘小航 栗婧 尚长岭 《安全与环境学报》 CAS CSCD 北大核心 2024年第7期2741-2750,共10页
安全生产事故往往由多组织交互、多因素耦合造成,事故原因涉及多个组织。为预防和遏制多组织生产安全事故的发生,基于系统理论事故建模与过程模型(Systems-Theory Accident Modeling and Process,STAMP)、24Model,构建一种用于多组织事... 安全生产事故往往由多组织交互、多因素耦合造成,事故原因涉及多个组织。为预防和遏制多组织生产安全事故的发生,基于系统理论事故建模与过程模型(Systems-Theory Accident Modeling and Process,STAMP)、24Model,构建一种用于多组织事故分析的方法,并以青岛石油爆炸事故为例进行事故原因分析。结果显示:STAMP-24Model可以分组织,分层次且有效、全面、详细地分析涉及多个组织的事故原因,探究多组织之间的交互关系;对事故进行动态演化分析,可得到各组织不安全动作耦合关系与形成的事故失效链及管控失效路径,进而为预防多组织事故提供思路和参考。 展开更多
关键词 安全工程 系统理论事故建模与过程模型(STAMP) 24model 多组织事故 原因分析
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Innovative approaches in high-speed railway bridge model simplification for enhanced computational efficiency
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作者 ZHOU Wang-bao XIONG Li-jun +1 位作者 JIANG Li-zhong ZHONG Bu-fan 《Journal of Central South University》 CSCD 2024年第11期4203-4217,共15页
In the realm of high-speed railway bridge engineering,managing the intricacies of the track-bridge system model(TBSM)during seismic events remains a formidable challenge.This study pioneers an innovative approach by p... In the realm of high-speed railway bridge engineering,managing the intricacies of the track-bridge system model(TBSM)during seismic events remains a formidable challenge.This study pioneers an innovative approach by presenting a simplified bridge model(SBM)optimized for both computational efficiency and precise representation,a seminal contribution to the engineering design landscape.Central to this innovation is a novel model-updating methodology that synergistically melds artificial neural networks with an augmented particle swarm optimization.The neural networks adeptly map update parameters to seismic responses,while enhancements to the particle swarm algorithm’s inertial and learning weights lead to superior SBM parameter updates.Verification via a 4-span high-speed railway bridge revealed that the optimized SBM and TBSM exhibit a highly consistent structural natural period and seismic response,with errors controlled within 7%.Additionally,the computational efficiency improved by over 100%.Leveraging the peak displacement and shear force residuals from the seismic TBSM and SBM as optimization objectives,SBM parameters are adeptly revised.Furthermore,the incorporation of elastoplastic springs at the beam ends of the simplified model effectively captures the additional mass,stiffness,and constraint effects exerted by the track system on the bridge structure. 展开更多
关键词 high-speed railway bridge engineering track-bridge system model simplified bridge model artificial neural networks particle swarm optimization seismic analysis
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Research on modeling of nonlinear vibration isolation system based on Bouce Wen model 被引量:2
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作者 Zhi-ling PENG Chun-gui ZHOU 《Defence Technology(防务技术)》 SCIE EI CAS 2014年第4期371-374,共4页
A feedforword neural network of multi-layer topologies for systems with hysteretic nonlinearity is constructed based on Bouce Wen differential model. It not only reflects the hysteresis force characteristics of the Bo... A feedforword neural network of multi-layer topologies for systems with hysteretic nonlinearity is constructed based on Bouce Wen differential model. It not only reflects the hysteresis force characteristics of the Bouce Wen model, but also determines its corresponding parameters. The simulation results show that restoring forceedisplacement curve hysteresis loop is very close to the real curve. The model trained can accurately predict the time response of system. The model is checked under the noise level. The result shows that the model has higher modeling precision, good generalization capability and a certain anti-interference ability. 展开更多
关键词 BOUC-WEN模型 建模精度 非线性隔振系统 迟滞非线性系统 基础 前馈神经网络 位移曲线 抗干扰能力
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Identification and nonlinear model predictive control of MIMO Hammerstein system with constraints 被引量:3
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作者 李大字 贾元昕 +1 位作者 李全善 靳其兵 《Journal of Central South University》 SCIE EI CAS CSCD 2017年第2期448-458,共11页
This work is concerned with identification and nonlinear predictive control method for MIMO Hammerstein systems with constraints. Firstly, an identification method based on steady-state responses and sub-model method ... This work is concerned with identification and nonlinear predictive control method for MIMO Hammerstein systems with constraints. Firstly, an identification method based on steady-state responses and sub-model method is introduced to MIMO Hammerstein system. A modified version of artificial bee colony algorithm is proposed to improve the prediction ability of Hammerstein model. Next, a computationally efficient nonlinear model predictive control algorithm(MGPC) is developed to deal with constrained problem of MIMO system. The identification process and performance of MGPC are shown. Numerical results about a polymerization reactor validate the effectiveness of the proposed method and the comparisons show that MGPC has a better performance than QDMC and basic GPC. 展开更多
关键词 model predictive control system identification constrained systems Hammerstein model polymerization reactor artificial bee colony algorithm
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An Improved H∞ Filter Design for Nonlinear System with Time-delay via T-S Fuzzy Models 被引量:1
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作者 HUANG Sheng-Juan ZHANG Da-Qing HE Xi-Qin ZHANG Ning-Ning 《自动化学报》 EI CSCD 北大核心 2010年第10期1454-1459,共6页
关键词 非线性系统 自动化系统 研究 模糊性
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Parameter estimation for multirate multi-input systems using auxiliary model and multi-innovation 被引量:3
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作者 Lili Han Feng Ding 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2010年第6期1079-1083,共5页
The multirate multi-input systems have different updating periods and sampling periods such that the conventional identification algorithms cannot be used to identify such multirate systems. By using the auxiliary mod... The multirate multi-input systems have different updating periods and sampling periods such that the conventional identification algorithms cannot be used to identify such multirate systems. By using the auxiliary model identification idea, the multiinnovation stochastic gradient algorithm is developed to estimate the parameters of multirate systems. Finally, an illustrative example is given to verify the effectiveness of the proposed algorithm. 展开更多
关键词 parameter estimation multirate systems multiinnovation auxiliary model.
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A New Method with High Confidence for Validation of Computer Simulation Models of Flight Systems 被引量:5
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作者 Zhou XianminShanghai Research & Development Centre, 412 Guil in Road, Shanghai 200233, P.R.China 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 1993年第4期43-52,共10页
Computer simulation models may by used to gain further information about missile performance variability. Model validation is an important aspect of the test program for a missile system. Validation provides a basis f... Computer simulation models may by used to gain further information about missile performance variability. Model validation is an important aspect of the test program for a missile system. Validation provides a basis for confidence in the model's results and is a necessary step if the model is to be used to draw inference about the behavior of the real missile. This paper is a review of methods useful for validation of computer simulation models of missile systems and provides a new method with high degree of confidence for validation of computer simulation models of missile systems. Some examples of the use of the new method in validating computer simulation models are given. 展开更多
关键词 model validation model credibility Simulation modeling system simulation.
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Uniformed model of networked control systems with long time delay 被引量:4
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作者 Zhu Qixin Liu Hongli Hu Shousong 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2008年第2期385-390,共6页
Feedback control systems wherein the control loops are closed through a real-time network are called networked control systems (NCS). The defining feature of an NCS is that information is exchanged using a network a... Feedback control systems wherein the control loops are closed through a real-time network are called networked control systems (NCS). The defining feature of an NCS is that information is exchanged using a network among control system components. Two new concepts including long time delay and short time delay are proposed. The sensor is almost always clock driven. The controller or the actuator is either clock driven or event driven. Four possible driving modes of networked control systems are presented. The open loop mathematic models of networked control systems with long time delay are developed when the system is driven by anyone of the four different modes. The uniformed modeling method of networked control systems with long time delay is proposed. The simulation results are given in the end. 展开更多
关键词 networked control systems time delay model driving mode.
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Building up a Mathematical Model of Shaftes System and CAD for Linked Tetra-Shaft and Double-Cantilever Flat Flap Gate 被引量:1
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作者 FuQ满怀 ZhaoZe-bin 《Journal of Northeast Agricultural University(English Edition)》 CAS 1999年第2期139-146,共8页
Linked tetra shaft and double cantilever flat flap gate is a new type of structure in water conservancy projects,but the traditional method is now adopted in its design.In order to the application and dissemination ... Linked tetra shaft and double cantilever flat flap gate is a new type of structure in water conservancy projects,but the traditional method is now adopted in its design.In order to the application and dissemination of the type of sluice,this paper researches the difficult points of design advance,through researching the motion locus & stress coundition of linked tetra shaft system.The writer will build up the mathmatical model and handle it with the computer.Thus,we can achieve the modern desing on the basis of the software of linked tetra shaft system development. 展开更多
关键词 linked tetra shaft flap gate shaft system mathematical model CAD
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Accuracy analysis of a single-fault Markov model for FADEC system 被引量:2
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作者 CAI Jing HU Wei CAI Kunye 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2019年第5期1044-1052,共9页
Time-limited dispatching(TLD)analysis of the full authority digital engine control(FADEC)systems is an important part of the aircraft system safety analysis and a necessary task for the certification of commercial air... Time-limited dispatching(TLD)analysis of the full authority digital engine control(FADEC)systems is an important part of the aircraft system safety analysis and a necessary task for the certification of commercial aircraft and aeroengines.In the time limited dispatch guidance document ARP5107B,a single-fault Markov model(MM)approach is proposed for TLD analysis.However,ARP5107B also requires that the loss of thrust control(LOTC)rate error calculated by applying the single-fault MM must be less than 5%when performing airworthiness certification.Firstly,the sources of accuracy errors in three kinds of MM are analyzed and specified through a case study of the general FADEC system,and secondly a two-fault MM considering maintenance policy is established through analyzing and calculating the expected repair time when two related faults happen.Finally,a specific FADEC system is given to study on the influence factors of accuracy error in the single-fault MM,and the results show that the accuracy error of the single-fault MM decreases with the increase of short or long prescribed dispatch time,and the range values of short time(ST)and long time(LT)are determined to satisfy the requirement of accuracy error within 5%. 展开更多
关键词 full AUTHORITY digital engine control(FADEC)system MARKOV model(MM) accuracy analysis loss of THRUST control(LOTC)
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XML-based integration data model and schema mappingin multidatabase systems 被引量:5
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作者 LiRuixuan 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2005年第2期437-444,共8页
Multidatabase systems are designed to achieve schema integration and data interoperation among distributed and heterogeneous database systems. But data model heterogeneity and schema heterogeneity make this a challeng... Multidatabase systems are designed to achieve schema integration and data interoperation among distributed and heterogeneous database systems. But data model heterogeneity and schema heterogeneity make this a challenging task. A multidatabase common data model is firstly introduced based on XML, named XML-based Integration Data Model (XIDM), which is suitable for integrating different types of schemas. Then an approach of schema mappings based on XIDM in multidatabase systems has been presented. The mappings include global mappings, dealing with horizontal and vertical partitioning between global schemas and export schemas, and local mappings, processing the transformation between export schemas and local schemas. Finally, the illustration and implementation of schema mappings in a multidatabase prototype - Panorama system are also discussed. The implementation results demonstrate that the XIDM is an efficient model for managing multiple heterogeneous data sources and the approaches of schema mapping based on XIDM behave very well when integrating relational, object-oriented database systems and other file systems. 展开更多
关键词 multidatabase systems common data model schema mapping extensible markup language (XML).
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A Systematic Analysis Approach to Discrete-time Indirect Model Reference Adaptive Control 被引量:1
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作者 XIE Xue-Jun LI Jun-Ling 《自动化学报》 EI CSCD 北大核心 2007年第11期1170-1175,共6页
这份报纸论述间接模型引用的设计和分析有为分离时间的系统的一个类的规范的适应法律的适应控制(MRAC ) 。主要工作包括三部分。第一,构造工厂参数评价算法不仅拥有传统的评价算法的象那些的一样的性质而且在零避免分割的可能性。第二... 这份报纸论述间接模型引用的设计和分析有为分离时间的系统的一个类的规范的适应法律的适应控制(MRAC ) 。主要工作包括三部分。第一,构造工厂参数评价算法不仅拥有传统的评价算法的象那些的一样的性质而且在零避免分割的可能性。第二,由发现在工厂参数之间的关系,估计和控制器参数估计并且用工厂参数的性质估计,控制器参数估计的类似的性质也被建立。第三,基于关系,在使正常化之间的性质发信号并且在靠近环的系统并且在分离时间的系统上的一些重要数学工具上的所有信号作为在连续时间的盒子中,到分离间接 MRAC 计划的系统的稳定性和集中分析途径严厉地被开发。 展开更多
关键词 模型参考自适应控制 不连续时间系统 标准化适应定律 系统分析
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A Complete Analytic Model for Fault Diagnosis of Power Systems 被引量:33
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作者 LIU Daobing GU Xueping LI Haipeng 《中国电机工程学报》 EI CSCD 北大核心 2011年第34期I0008-I0008,10,共1页
现代大规模互联电网提高了电力系统运行的稳定性和经济性,同时也给电网的故障诊断增加了难度。对电网保护配置和断路器动作规则进行深入分析,提出一种新的电网故障诊断模型——完全解析模型,并为基于此模型的故障诊断提出一种实用有效... 现代大规模互联电网提高了电力系统运行的稳定性和经济性,同时也给电网的故障诊断增加了难度。对电网保护配置和断路器动作规则进行深入分析,提出一种新的电网故障诊断模型——完全解析模型,并为基于此模型的故障诊断提出一种实用有效的求解方法。在完全解析模型中,故障假说(即可疑故障设备的故障情况)与保护、断路器的动作情况及拒动和误动情况一同表示成逻辑变量,而保护配置和断路器动作规则以逻辑方程组形式进行充分表达,逻辑方程组的每个解析解对应一个故障模式(设备故障状态和保护动作、断路器跳闸状态及拒动/误动情况),是对故障情形的完整解释。本模型对故障诊断规则和保护、断路器的动作逻辑进行完全解析,并完整保留了故障设备、保护动作和断路器跳闸之间的耦合关系,克服了已有解析模型的缺陷。算例表明,保留完整耦合关系的完全解析模型可有效提高故障诊断的准确性和容错能力。 展开更多
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