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A scattering matrix approach to quantum pumping:beyond the small-AC-driving-amplitude limit 被引量:4
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作者 朱瑞 《Chinese Physics B》 SCIE EI CAS CSCD 2010年第12期437-442,共6页
In the adiabatic and weak-modulation quantum pump, net electron flow is driven from one reservoir to another by absorbing or emitting an energy quantum nω from or to the reservoirs. This paper considers high-order de... In the adiabatic and weak-modulation quantum pump, net electron flow is driven from one reservoir to another by absorbing or emitting an energy quantum nω from or to the reservoirs. This paper considers high-order dependence of the scattering matrix on the time. Non-sinusoidal behaviour of strong pumping is revealed. The relation between the pumped current and the ac driving amplitude varies from power of 2, 1 to 1/2 when stronger modulation is exerted. Open experimental observation can be interpreted by multi-energy-quantum-related processes. 展开更多
关键词 quantum pumping scattering matrix approach multi-energy-quantum-related processes
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Cauchy matrix approach to three non-isospectral nonlinear Schrödinger equations 被引量:1
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作者 Alemu Yilma Tefera Shangshuai Li Da-jun Zhang 《Communications in Theoretical Physics》 SCIE CAS CSCD 2024年第5期1-15,共15页
This paper aims to develop a direct approach,namely,the Cauchy matrix approach,to non-isospectral integrable systems.In the Cauchy matrix approach,the Sylvester equation plays a central role,which defines a dressed Ca... This paper aims to develop a direct approach,namely,the Cauchy matrix approach,to non-isospectral integrable systems.In the Cauchy matrix approach,the Sylvester equation plays a central role,which defines a dressed Cauchy matrix to provideτfunctions for the investigated equations.In this paper,using the Cauchy matrix approach,we derive three non-isospectral nonlinear Schrödinger equations and their explicit solutions.These equations are generically related to the time-dependent spectral parameter in the Zakharov–Shabat–Ablowitz–Kaup–Newell–Segur spectral problem.Their solutions are obtained from the solutions of unreduced non-isospectral nonlinear Schrödinger equations through complex reduction.These solutions are analyzed and illustrated to show the non-isospectral effects in dynamics of solitons. 展开更多
关键词 Cauchy matrix approach Sylvester equation nonlinear Schrödinger equation non-isospectral integrable system explicit solution
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Transfer Matrix Approach for Two-State Scattering Problem with Arbitrary Coupling
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作者 Diwaker Aniruddha Chakraborty 《Chinese Physics Letters》 SCIE CAS CSCD 2015年第7期5-8,共4页
The present work deals with the calculation of transition probability between two diabatic potentials coupled by any arbitrary coupling. The method presented in this work is applicable to any type of coupling while fo... The present work deals with the calculation of transition probability between two diabatic potentials coupled by any arbitrary coupling. The method presented in this work is applicable to any type of coupling while for numerical calculations we have assumed the arbitrary coupling as Gaussian coupling. This arbitrary coupling is expressed as a collection of Dirac delta functions and by the use of the transfer matrix technique the transition probability from one diabatic potential to another diabatic potential is calculated. We examine our approach by considering the case of two constant potentials coupled by Gaussian coupling as an arbitrary coupling. 展开更多
关键词 Transfer matrix approach for Two-State Scattering Problem with Arbitrary Coupling
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Graph Theory and Matrix Approach(GTMA)Model for the Selec­tion of the Femoral-Component of Total Knee Joint Replacement
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作者 Amber Gul Malik Naqash Mehmood Malik Sajjad Mehmood 《Non-Metallic Material Science》 2021年第1期1-9,共9页
Total Knee Replacement(TKR)is the increasing trend now a day,in revision surgery which is associated with aseptic loosening,which is a challenging research for the TKR component.The selection of optimal material loose... Total Knee Replacement(TKR)is the increasing trend now a day,in revision surgery which is associated with aseptic loosening,which is a challenging research for the TKR component.The selection of optimal material loosening can be controlled at some limits.This paper is going to consider the best material selected among a number of alternative materials for the femoral component(FC)by using Graph Theory.Here GTMA process used for optimization of material and a systematic technique introduced through sensitivity analysis to find out the more reliable result.Obtained ranking suggests the use of optimized material over the other existing material.By following GTMA Co_Cr-alloys(wrought-Co-Ni-Cr-Mo)and Co_Cr-alloys(cast-able-Co-Cr-Mo)are on the 1st and 2nd position respectively. 展开更多
关键词 Femoral component Knee replacement Graph theory and matrix approach Sensitivity analysis
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A Matrix Approach to Study Prism-Waveguide Coupler
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作者 金恩培 叶奕煌 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 1995年第3期11-13,共3页
AMatrixApproachtoStudyPrism-WaveguideCouplerJINEnpei;YEYihuang金恩培,叶奕煌(DepartmentofPhysics,HarbinInstituteofT... AMatrixApproachtoStudyPrism-WaveguideCouplerJINEnpei;YEYihuang金恩培,叶奕煌(DepartmentofPhysics,HarbinInstituteofTechnology,Harbin,... 展开更多
关键词 ss: Optical WAVEGUIDE PRISM COUPLER matrix approach
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A Vicious Script in HTML Detection Method Using Judgment Matrix Approach
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作者 李志勇 张昊 +1 位作者 陶然 杜华 《Defence Technology(防务技术)》 SCIE EI CAS 2009年第1期76-80,共5页
A vicious script detection method based on statistic is proposed by analyzing the vicious script in the hypertext markup language(HTML).We utilize the judgment matrix approach which is one of the subjective weighting ... A vicious script detection method based on statistic is proposed by analyzing the vicious script in the hypertext markup language(HTML).We utilize the judgment matrix approach which is one of the subjective weighting approaches to set the different weights for various statistic methods.Then we make use of the weighted geometric method to perfect the statistic results.Experimental results show the validity of this method. 展开更多
关键词 判断矩阵 HTML 脚本 恶性 检测 超文本标记语言 统计分析 加权方法
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Wide-Area Delay-Dependent Adaptive Supervisory Control of Multi-machine Power System Based on Improve Free Weighting Matrix Approach
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作者 Ziyong Zhang Zhijian Hu +3 位作者 Yukai Liu Yang Gao He Wang Jianglei Suo 《Energy and Power Engineering》 2013年第4期435-441,共7页
The paper demonstrates the possibility to enhance the damping of inter-area oscillations using Wide Area Measurement (WAM) based adaptive supervisory controller (ASC) which considers the wide-area signal transmission ... The paper demonstrates the possibility to enhance the damping of inter-area oscillations using Wide Area Measurement (WAM) based adaptive supervisory controller (ASC) which considers the wide-area signal transmission delays. The paper uses an LMI-based iterative nonlinear optimization algorithm to establish a method of designing state-feedback controllers for power systems with a time-varying delay. This method is based on the delay-dependent stabilization conditions obtained by the improved free weighting matrix (IFWM) approach. In the stabilization conditions, the upper bound of feedback signal’s transmission delays is taken into consideration. Combining theoriesof state feedback control and state observer, the ASC is designed and time-delay output feedback robust controller is realized for power system. The ASC uses the input information from Phase Measurement Units (PMUs) in the system and dispatches supplementary control signals to the available local controllers. The design of the ASC is explained in detail and its performance validated by time domain simulations on a New England test power system (NETPS). 展开更多
关键词 ADAPTIVE Supervisory Controller (ASC) DELAY-DEPENDENT Damping Control Power Oscillation IFWM LMI Free Weighting matrix approach TIME-VARYING Delay WAMS
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A Relation Matrix Approach to Labelling Temporal Relations in Scheduling
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作者 张钹 张铃 《Journal of Computer Science & Technology》 SCIE EI CSCD 1991年第4期339-346,共8页
In this paper,we present a relation matrix description of temporal relations.Based on this modela new algorithm for labelling temporal relations is proposed.Under certain conditions the algorithm iscompleted and has a... In this paper,we present a relation matrix description of temporal relations.Based on this modela new algorithm for labelling temporal relations is proposed.Under certain conditions the algorithm iscompleted and has a polynomial complexity.In general cases it is still an efficient algorithm comparedto some known algorithms. 展开更多
关键词 A Relation matrix approach to Labelling Temporal Relations in Scheduling
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A Novel Approach to Practical Matrix Converter Motor Drive System With Reverse Blocking IGBT
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《变频器世界》 2006年第7期25-26,共2页
a Pole voltage waveforms (VA20 and VA40) for modulation index 0.4 (middle trace is A-phase voltage waveform) x-axis: 1 div.=10ms, y-axis: 1 div.= 100V b Normalized harmonic spectrum for pole voltage of Fig. 9a c A-pha... a Pole voltage waveforms (VA20 and VA40) for modulation index 0.4 (middle trace is A-phase voltage waveform) x-axis: 1 div.=10ms, y-axis: 1 div.= 100V b Normalized harmonic spectrum for pole voltage of Fig. 9a c A-phase current and phase voltage for modulation index 0.4 (reference space vector is in inner layer) 展开更多
关键词 A Novel approach to Practical matrix Converter Motor Drive System With Reverse Blocking IGBT mode PWM
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A Novel Approach to Practical Matrix Converter Motor Drive System With Reverse Blocking IGBT (To continue)
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《变频器世界》 2006年第8期28-29,共2页
a Pole voltage waveforms (VA20 and VA40) for modulation index 0.4 (middle trace is A-phase voltage waveform) x-axis: 1 div.=10ms, y-axis: 1 div.= 100V b Normalized harmonic spectrum for pole voltage of Fig. 9a c A-pha... a Pole voltage waveforms (VA20 and VA40) for modulation index 0.4 (middle trace is A-phase voltage waveform) x-axis: 1 div.=10ms, y-axis: 1 div.= 100V b Normalized harmonic spectrum for pole voltage of Fig. 9a c A-phase current and phase voltage for modulation index 0.4 (reference space vector is in inner layer) 展开更多
关键词 口口 口门 mode To continue A Novel approach to Practical matrix Converter Motor Drive System With Reverse Blocking IGBT
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Semi-tensor product approach to controllability and stabilizability of finite automata 被引量:14
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作者 Yongyi Yan Zengqiang Chen Zhongxin Liu 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2015年第1期134-141,共8页
Using semi-tensor product of matrices, the controllability and stabilizability of finite automata are investigated. By expressing the states, inputs, and outputs in vector forms, the transition and output functions ar... Using semi-tensor product of matrices, the controllability and stabilizability of finite automata are investigated. By expressing the states, inputs, and outputs in vector forms, the transition and output functions are represented in matrix forms.Based on this algebraic description, a necessary and sufficient condition is proposed for checking whether a state is controllable to another one. By this condition, an algorithm is established to find all the control sequences of an arbitrary length. Moreover, the stabilizability of finite automata is considered, and a necessary and sufficient condition is presented to examine whether some states can be stabilized. Finally, the study of illustrative examples verifies the correctness of the presented results/algorithms. 展开更多
关键词 finite automata CONTROLLABILITY STABILIZABILITY semitensor product of matrices matrix approach
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Cauchy matrix structure of the Mel’nikov model of long-short wave interaction 被引量:2
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作者 Hong-Juan Tian Da-Jun Zhang 《Communications in Theoretical Physics》 SCIE CAS CSCD 2020年第12期83-93,共11页
We propose a systematic method to construct the Mel’nikov model of long–short wave interactions,which is a special case of the Kadomtsev–Petviashvili(KP)equation with self-consistent sources(KPSCS).We show details ... We propose a systematic method to construct the Mel’nikov model of long–short wave interactions,which is a special case of the Kadomtsev–Petviashvili(KP)equation with self-consistent sources(KPSCS).We show details how the Cauchy matrix approach applies to Mel’nikov’s model which is derived as a complex reduction of the KPSCS.As a new result wefind that in the dispersion relation of a 1-soliton there is an arbitrary time-dependent function that has previously not reported in the literature about the Mel’nikov model.This function brings time variant velocity for the long wave and also governs the short-wave packet.The variety of interactions of waves resulting from the time-freedom in the dispersion relation is illustrated. 展开更多
关键词 Mel’nikov model of long–short wave interaction Cauchy matrix approach self-consistent sources KP equation
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Near-field 3D imaging approach combining MJSR and FGG-NUFFT 被引量:3
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作者 WANG Shuzhen FANG Yang +2 位作者 ZHANG Jin’gang LUO Mingshi LI Qing 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2019年第6期1096-1109,共14页
A near-field three-dimensional(3 D)imaging method combining multichannel joint sparse recovery(MJSR)and fast Gaussian gridding nonuniform fast Fourier transform(FGGNUFFT)is proposed,based on a perfect combination of t... A near-field three-dimensional(3 D)imaging method combining multichannel joint sparse recovery(MJSR)and fast Gaussian gridding nonuniform fast Fourier transform(FGGNUFFT)is proposed,based on a perfect combination of the compressed sensing(CS)theory and the matched filtering(MF)technique.The approach has the advantages of high precision and high efficiency:multichannel joint sparse constraint is adopted to improve the problem that the images recovered by the single channel imaging algorithms do not necessarily share the same positions of the scattering centers;the CS dictionary is constructed by combining MF and FGG-NUFFT,so as to improve the imaging efficiency and memory requirement.Firstly,a near-field 3 D imaging model of joint sparse recovery is constructed by combining the MF-based imaging method.Secondly,FGG-NUFFT and reverse FGG-NUFFT are used to replace the interpolation and Fourier transform in MF-based imaging methods,and a sensing matrix with high precision and high efficiency is constructed according to the traditional imaging process.Thirdly,a fast imaging recovery is performed by using the improved separable surrogate functionals(SSF)optimization algorithm,only with matrix and vector multiplication.Finally,a 3 D imagery of the near-field target is obtained by using both the horizontal and the pitching interferometric phase information.This paper contains two imaging models,the only difference is the sub-aperture method used in inverse synthetic aperture radar(ISAR)imaging.Compared to traditional CS-based imaging methods,the proposed method includes both forward transform and inverse transform in each iteration,which improves the quality of reconstruction.The experimental results show that,the proposed method improves the imaging accuracy by about O(10),accelerates the imaging speed by five times and reduces the memory usage by about O(10~2). 展开更多
关键词 interference imaging joint sparse recovery compressed sensing(CS) matching filtering(MF) fast Gaussian gridding nonuniform fast Fourier transform(NUFFT) near-field 3D imaging
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Risk assessment: an approach to control hazards in mines 被引量:2
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作者 Shis Bhattacherjee 《中国安全生产科学技术》 CAS CSCD 2014年第S1期129-135,共7页
Accidents and injuries related to work are major occupational health problems in most of the industrialized countries.Traditional approaches to manage workplace safety in mines have mainly focused on job redesign and ... Accidents and injuries related to work are major occupational health problems in most of the industrialized countries.Traditional approaches to manage workplace safety in mines have mainly focused on job redesign and technical aspects of engineering systems.It is being realized that compliance to rules and regulations of mines is a prerequisite;however,it is not sufficient to achieve further reduction in accident and injury rates in mines.Proactive approaches are necessary to further improve the safety standards in mines.Unsafe conditions and practices in mines lead to a number of accidents,which in turn may cause loss and injury to human lives,damages to property,and loss of production.Hazard identification and risk assessment is an important task for the mining industry which needs to consider all the risk factors at workplaces.Applications of risk management approaches in mines are necessary to identify and quantify potential hazards and to suggest effective solutions.In this paper,the following risk estimation techniques were discussed:(i)DGMS(Directorate General of Mines Safety,India)risk rating criterion,and(ii)a matrix based approach.The proposed tools were demonstrated through an application in an opencast coal mine in India.It was inferred that the risk assessment approach can be used as an effective tool to indentify and control hazards in mines. 展开更多
关键词 HAZARD identification RISK ASSESSMENT DGMS matrix based approach
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Ranking Method for Complementary Judgment Matrixes with Fuzzy Numbers Based on Hausdorff Metric Distance 被引量:1
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作者 侯福均 吴祈宗 《Journal of Beijing Institute of Technology》 EI CAS 2005年第4期458-461,共4页
A method for ranking complementary judgment matrixes with traspezoidal fuzzy numbers based on Hausdorff metric distance and fuzzy compromise decision approach is proposed. With regard to fuzzy number complementary jud... A method for ranking complementary judgment matrixes with traspezoidal fuzzy numbers based on Hausdorff metric distance and fuzzy compromise decision approach is proposed. With regard to fuzzy number complementary judgment matrixes given by a decider group whose members have various weights, the expert's information was aggregated first by means of simple weight average(SWA) method and Bonissone calculational method. Hence a matrix including all the experts' preference information was got. Then the matrix' column members were added up and the fuzzy evaluation values of the alternatives were got. Lastly, the Hausdorff metric distance and fuzzy compromise decision approach were used to rank the fuzzy evaluation values and then the ranking values of all the alternatives were got. Because exact numbers and triangular fuzzy numbers could all be transformed into trapezoidal fuzzy numbers, the method developed can rank complementary judgment matrixes with trapezoidal fuzzy numbers, triangular fuzzy numbers and exact numbers as well. An illustrative example is also given to verify the developed method and to demonstrate its feasibility and practicality. 展开更多
关键词 complementary judgment matrix trapezoidal fuzzy number Bonissone calculational method fuzzy compromise decision approach Hausdorff metric distance
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Squeezed Coherent States in Non-Unitary Approach and Relation to Sub- and Super-Poissonian Statistics
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作者 Alfred Wünsche 《Advances in Pure Mathematics》 2017年第12期706-757,共52页
After developing the concept of displaced squeezed vacuum states in the non-unitary approach and establishing the connection to the unitary approach we calculate their quasiprobabilities and expectation values in gene... After developing the concept of displaced squeezed vacuum states in the non-unitary approach and establishing the connection to the unitary approach we calculate their quasiprobabilities and expectation values in general form. Then we consider the displacement of the squeezed vacuum states and calculate their photon statistics and their quasiprobabilities. The expectation values of the displaced states are related to the expectation values of the undisplaced states and are calculated for some simplest cases which are sufficient to discuss their categorization as sub-Poissonian and super-Poissonian statistics. A large set of these states do not belong to sub- or to super-Poissonian states but are also not Poissonian states. We illustrate in examples their photon distributions. This shows that the notions of sub- and of super-Poissonian statistics and their use for the definition of nonclassicality of states are problematic. In Appendix A we present the most important relations for SU (1,1) treatment of squeezing and the disentanglement of their operators. Some initial members of sequences of expectation values for squeezed vacuum states are collected in Appendix E. 展开更多
关键词 SU (1 1) Group of SQUEEZING and Rotation WIGNER Quasiprobability Unitary approach to SQUEEZING NONCLASSICAL STATES Uncertainty matrix Distance of STATES Jacobi Ultraspherical LEGENDRE and Hermite Polynomials Poisson STATISTICS
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MOCHA:一种面向移动自组织网络的分布式机器学习优化方法
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作者 赵玮 赵佳 《长春工程学院学报(自然科学版)》 2025年第2期87-93,共7页
针对移动自组织网络中设备性能的异构性和网络拓扑的动态变化,提出了一种面向移动自组织网络的分布式机器学习优化方法(A Distributed Machine Learning Optimization Method for Mobile Adhoc Networks,MOCHA),MOCHA创新性地引入了基... 针对移动自组织网络中设备性能的异构性和网络拓扑的动态变化,提出了一种面向移动自组织网络的分布式机器学习优化方法(A Distributed Machine Learning Optimization Method for Mobile Adhoc Networks,MOCHA),MOCHA创新性地引入了基于设备计算能力、电量等性能指标的通信概率机制,并通过目标值子矩阵法完成最优适配,最后以模型参数的传递完成设备间信息的交互。理论分析与试验结果表明,相比传统的分布式学习方法,MOCHA在移动环境下展现出了显著的性能提升优势,为移动分布式机器学习实践提供了新的思路。 展开更多
关键词 移动自组织网络 分散式训练 目标值子矩阵法
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混合基质气体分离膜渗透性能模型的研究进展 被引量:1
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作者 赵娟 艾宏儒 《化工新型材料》 北大核心 2025年第1期54-61,共8页
混合基质膜(MMMs)通过结合无机填料的优异选择性和聚合物基质的卓越渗透性,展现出超越传统聚合物膜的气体分离性能。针对目前流行的用于预测混合基质膜的有效介质(EMA)渗透模型,讨论了其基本假设和局限性。通过对渗透模型预测值与实验... 混合基质膜(MMMs)通过结合无机填料的优异选择性和聚合物基质的卓越渗透性,展现出超越传统聚合物膜的气体分离性能。针对目前流行的用于预测混合基质膜的有效介质(EMA)渗透模型,讨论了其基本假设和局限性。通过对渗透模型预测值与实验数据的比较分析,揭示了这些模型在预测MMMs渗透性能时的应用范围。在此基础上,提出了未来模型发展的方向,旨在为高性能气体分离膜材料的设计和优化提供理论基础和指导。 展开更多
关键词 混合基质膜 气体分离 数学模型 有效介质法 渗透性能
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基于全驱系统方法的非线性系统的自适应事件触发控制
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作者 彭王冲 崔阳 牛芳琳 《辽宁科技大学学报》 2025年第2期120-129,共10页
针对一类带有未知控制增益矩阵的高阶非线性全驱系统,提出一种鲁棒自适应事件触发控制的全驱系统方法。控制器设计包括三部分,基础部分能够消除系统中已知的非线性项,指定闭环系统中线性主导项,鲁棒部分能够克服未知非线性项对系统的影... 针对一类带有未知控制增益矩阵的高阶非线性全驱系统,提出一种鲁棒自适应事件触发控制的全驱系统方法。控制器设计包括三部分,基础部分能够消除系统中已知的非线性项,指定闭环系统中线性主导项,鲁棒部分能够克服未知非线性项对系统的影响,自适应部分能够在线调整以适应未知参数的影响。通过未知控制增益的有界性及不等式放缩,能够有效减小其对系统的影响。通过引入新的事件触发控制机制,可以减少不必要的控制更新,增加系统的灵活性。仿真证明控制方法的有效性及优势。 展开更多
关键词 全驱系统方法 鲁棒自适应控制 未知控制增益矩阵 事件触发控制
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景观格局分析法与土地利用转换矩阵在土地利用特征研究中的应用 被引量:35
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作者 蔡为民 唐华俊 +1 位作者 吕钢 陈佑启 《中国土地科学》 CSSCI 北大核心 2006年第1期39-44,共6页
研究目的:以黄河三角洲为例,研究景观格局分析方法与土地利用转换矩阵在土地利用特征研究中的应用。研究方法:景观格局分析和土地利用转换矩阵。研究结果:近20年山东省来东营市的土地利用主导变化过程是耕地、城镇建设用地、农村居民点... 研究目的:以黄河三角洲为例,研究景观格局分析方法与土地利用转换矩阵在土地利用特征研究中的应用。研究方法:景观格局分析和土地利用转换矩阵。研究结果:近20年山东省来东营市的土地利用主导变化过程是耕地、城镇建设用地、农村居民点用地增加,天然草地大量减少,土地利用类型有向单一化发展的趋势。这种土地利用模式对黄河三角洲地区发展、湿地保护是不利的,应该引起足够的重视。研究结论:将景观格局分析法和土地利用转换矩阵结合,可以快速的对一个地区的土地利用特征进行定性理解和定量分析,为政府管理部门提供数据支持和决策依据。 展开更多
关键词 土地资源 土地利用转换矩阵 景观格局分析法 黄河三角洲
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