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也说周遍性构式中的“都”和“也” 被引量:2
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作者 张怡春 《汉语学习》 CSSCI 北大核心 2011年第4期29-35,共7页
周遍性构式中,"都"分布自由,"也"分布受限;"都"倾向于肯定形式,"也"倾向于否定形式;"都/也"有时可互换而构式义不变。针对这些现象,本文从句法演变的角度和构式与"都/也"... 周遍性构式中,"都"分布自由,"也"分布受限;"都"倾向于肯定形式,"也"倾向于否定形式;"都/也"有时可互换而构式义不变。针对这些现象,本文从句法演变的角度和构式与"都/也"的互动入手,考察"都/也"的不均衡分布,提出构式义与"都/也"语义的融合以及构式形成过程中"前附词"的脱落或产生等解释性理论和说明。 展开更多
关键词 构式义 语义融合 “不论什么……都” “连……都/也”
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Characterization of discontinuous yielding phenomenon in isothermal compression of TC8 titanium alloy 被引量:3
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作者 王柯 李淼泉 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2016年第6期1583-1588,共6页
The discontinuous yielding phenomenon (DYP) during high temperature deformation was investigated based on the isothermal compression of TC8 titanium alloy. The DYP of TC8 titanium alloy was characterized by quan... The discontinuous yielding phenomenon (DYP) during high temperature deformation was investigated based on the isothermal compression of TC8 titanium alloy. The DYP of TC8 titanium alloy was characterized by quantifying the yield drop of the DYP (△σUL) and ending strain of flow oscillation (εOSC) based on the flow stress?strain curves, and then the effect of deformation parameters on the △σUL and εOSC values was analyzed. The results show that the △σUL and εOSC values increase with the increase of strain rate. The effect of deformation temperature on the ?σUL value depends on the strain rate. Finally, the transmission electron microscope (TEM) observation shows the evidence for the dynamic theory, which ascribes the DYP to the generation of mobile dislocation at the grain boundary. Meanwhile, the optical microscope (OM) observation shows that both the primary α grain and β grain become smaller with the increase of strain, which well interprets the effect of deformation parameters on the △σUL and εOSC values. 展开更多
关键词 titanium alloy flow stress discontinuous yielding dynamic theory
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The Theory of Field-Effect Transistors:XI. The Bipolar Electrochemical Currents(1-2-MOS-Gates on Thin-Thick Pure-Impure Base)
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作者 薩支唐 揭斌斌 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2008年第3期397-409,共13页
The field-effect transistor is inherently bipolar, having simultaneously electron and hole surface and volume channels and currents. The channels and currents are controlled by one or more externally applied transvers... The field-effect transistor is inherently bipolar, having simultaneously electron and hole surface and volume channels and currents. The channels and currents are controlled by one or more externally applied transverse electric fields. It has been known as the unipolar field-effect transistor for 55-years since Shockley's 1952 invention,because the electron-current theory inevitably neglected the hole current from over-specified internal and boundary conditions, such as the electrical neutrality and the constant hole-electrochemical-potential, resulting in erroneous solutions of the internal and terminal electrical characteristics from the electron channel current alone, which are in gross error when the neglected hole current becomes comparable to the electron current, both in subthreshold and strong inversion. This report presents the general theory, that includes both electron and hole channels and currents. The rectangular ( x, y, z) parallelepiped transistors,uniform in the width direction (z-axis),with one or two MOS gates on thin and thick,and pure and impure base, are used to illustrate the two-dimensional effects and the correct internal and boundary conditions for the electric and the electron and hole electrochemical potentials. Complete analytical equations of the DC current-voltage characteristics of four common MOS transistor structures are derived without over-specification: the 1-gate on semi-infinite-thick impure-base (the traditional bulk transistor), the 1-gate on thin impure-silicon layer over oxide-insulated silicon bulk (SOI) ,the 1-gate on thin impure-silicon layer deposited on insulating glass (SOI TFT), and the 2-gates on thin pure-base (FinFETs). 展开更多
关键词 bipolar field-effect transistor theory MOS field-effect transistor simultaneous electron and hole surface and volume channels and currents surface potential two-section short-channel theory double-gate impure-base theory
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Invariant Determinants in Banach Algebras
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作者 许天周 《Journal of Beijing Institute of Technology》 EI CAS 1997年第1期25-29,共5页
The invariant determinants ha Banach algebras are discussed and a necessary and sufficient condition for those integral traced unital Barach algebra(A,τ) admitting a G-invari- ant determinant is obtained,where G is a... The invariant determinants ha Banach algebras are discussed and a necessary and sufficient condition for those integral traced unital Barach algebra(A,τ) admitting a G-invari- ant determinant is obtained,where G is a group of trace preserving automorphisms of A. 展开更多
关键词 TRACE invariant determinant K-theory group Banach algebra
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'The Theory of Field-Effect Transistors XII.The Bipolar Drift and Diffusion Currents(1-2-MOS-Gates on Thin-Thick Pure-Impure Base)
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作者 揭斌斌 薩支唐 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2008年第7期1227-1241,共15页
The previous report (XI) gave the electrochemical-potential theory of the Bipolar Field-Effect Transistors. This report (XII) gives the drift-diffusion theory. Both treat 1-gate and 2-gate, pure-base and impure-ba... The previous report (XI) gave the electrochemical-potential theory of the Bipolar Field-Effect Transistors. This report (XII) gives the drift-diffusion theory. Both treat 1-gate and 2-gate, pure-base and impure-base, and thin and thick base. Both utilize the surface and bulk potentials as the parametric variables to couple the voltage and current equations. In the present drift-diffusion theory, the very many current terms are identified by their mobility multiplier for the components of drift current,and the diffusivity multiplier for the components of the diffusion current. Complete analytical driftdiffusion equations are presented to give the DC current-voltage characteristics of four common MOS transistor structures. The drift current consists of four terms: 1-D (One-Dimensional) bulk charge drift term, 1-D carrier space-charge drift term,l-D Ex^2 (transverse electric field) drift term,2-D drift term. The diffusion current consists of three terms: 1-D bulk charge diffusion term,l-D carrier space-charge diffusion term,and 2-D diffusion term. The 1-D Ex^2 drift term was missed by all the existing transistor theories, and contributes significantly, as much as 25 % of the total current when the base layer is nearly pure. The 2-D terms come from longitudinal gradient of the longitudinal electric field,which scales as the square of the Debye to Channel length ratio, at 25nm channel length with nearly pure base, (LD/L)^2 = 10^6 but with impurity concentration of 10^18cm^-3 , (LD/L)^2 = 10^-2 . 展开更多
关键词 bipolar field-effect transistor theory surface potential drift and diffusion theory single-gate impure-base double-gate impure-base
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IMPROVEMENT OF MATRIX REPRESENTATION METHOD IN NORMAL FORM THEORY 被引量:1
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作者 韩景龙 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2002年第2期166-171,共6页
In this paper, based on the invariant subspace theory and adjoint operator concept of linear operator, a new matrix representation method is proposed to calculate the normal forms of n order general nonlinear dyna... In this paper, based on the invariant subspace theory and adjoint operator concept of linear operator, a new matrix representation method is proposed to calculate the normal forms of n order general nonlinear dynamic systems. In the method, there is no need to determine the structure of the class of normal forms in advance. Because the subspace is not related to the dimensions of the system and the order of the normal forms directly, it is determined only by a given vector field. So the normal forms with high orders and dimensions can be calculated by the method without difficulties. In this paper, is used the method for selecting the minimal subspace and solving homological equations in the subspace, the examples show that the method is very effective. 展开更多
关键词 dynamic system normal forms NONLINEARITY linear space adjoint operator
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Seismological method for prediction of areal rockbursts in deep mine with seismic source mechanism and unstable failure theory 被引量:23
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作者 唐礼忠 XIA K W 《Journal of Central South University》 SCIE EI CAS 2010年第5期947-953,共7页
The research on the rock burst prediction was made on the basis of seismology,rock mechanics and the data from Dongguashan Copper Mine(DCM) ,the deepest metal mine in China.The seismic responses to mining in DCM were ... The research on the rock burst prediction was made on the basis of seismology,rock mechanics and the data from Dongguashan Copper Mine(DCM) ,the deepest metal mine in China.The seismic responses to mining in DCM were investigated through the analyses of the spatio-temporal distribution of hypocenters,apparent stress and displacement of seismic events,and the process of the generation of hazardous seismicity in DCM was studied in the framework of the theory of asperity in the seismic source mechanism.A method of locating areas with hazardous seismicity and a conceptual model of hazardous seismic nucleation in DCM were proposed.A criterion of rockburst prediction was analyzed theoretically in the framework of unstable failure theories,and consequently,the rate of change in the ratio of the seismic stiffness of rock in a seismic nucleation area to that in surrounding area,dS/dt,is defined as an index of the rockburst prediction.The possibility of a rockburst will increase if dS/dt>0,and the possibility of rock burst will decrease if dS/dt<0.The correctness of these methods is demonstrated by analyses of rock failure cases in DCM. 展开更多
关键词 areal rockburst prediction seismic source mechanism unstable failure deep mine seismic stiffness seismic nucleation
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The Optimal Nash Equilibrium Strategies Under Competition 被引量:1
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作者 孟力 王崇喜 +1 位作者 汪定伟 张爱玲 《Journal of Shanghai Jiaotong university(Science)》 EI 2004年第4期91-96,共6页
This paper presented a game theoretic model to study the competition for a single investment oppertunity under uncertainty. It models the hazard rate of investment as a function of competitors' trigger level. Unde... This paper presented a game theoretic model to study the competition for a single investment oppertunity under uncertainty. It models the hazard rate of investment as a function of competitors' trigger level. Under uncertainty and different information structure, the option and game theory was applied to researching the optimal Nash equilibrium strategies of one or more firm. By means of Matlab software, the paper simulates a real estate developing project example and illustrates how parameter affects investment strategies. The paper's work will contribute to the present investment practice in China. 展开更多
关键词 real options irreversible investment game theory UNCERTAINTY
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秦汉律中的“失刑罪”
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作者 宋磊 《古代文明(中英文)》 CSSCI 2021年第4期105-113,M0006,共10页
秦汉律中专门追究司法责任的罪名有“不直”“纵囚”和“失刑罪”,其中“失刑罪”是指司法中因过失造成的定罪量刑失当。“失刑罪”的渊源十分久远,但“失刑罪”的发展却是在春秋时期铸刑书刑鼎以后的罪刑严格精准对应时代。秦汉时期通... 秦汉律中专门追究司法责任的罪名有“不直”“纵囚”和“失刑罪”,其中“失刑罪”是指司法中因过失造成的定罪量刑失当。“失刑罪”的渊源十分久远,但“失刑罪”的发展却是在春秋时期铸刑书刑鼎以后的罪刑严格精准对应时代。秦汉时期通过覆讯、覆治(覆狱)、乞鞫、监御史和刺史监察劾举、录囚和使者循行“举冤狱”等多种途径发现和纠正“失刑罪”。“失刑罪”的罪名在秦末短暂消失,在汉代以后彻底消亡,但其体现出来的严格、精确追究司法责任的精神却为后世法律所沿用,并影响深远。 展开更多
关键词 失刑罪 司法责任 举冤狱 失纵不直论令 官司出入人罪
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Application of Bipartite and Tripartite Entangled State Representations in Quantum Teleportation of Continuous Variables 被引量:1
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作者 YUAN Hong-Chun QI Kai-Guo 《Communications in Theoretical Physics》 SCIE CAS CSCD 2005年第2X期269-273,共5页
We mostly investigate two schemes. One is to teleport a multi-mode W-type entangled coherent state using a peculiar bipartite entangled state as the quantum channel different from other proposals. Based on our formali... We mostly investigate two schemes. One is to teleport a multi-mode W-type entangled coherent state using a peculiar bipartite entangled state as the quantum channel different from other proposals. Based on our formalism,teleporting multi-mode coherent state or squeezed state is also possible. Another is that the tripartite entangled state is used as the quantum channel of controlled teleportation of an arbitrary and unknown continuous variable in the case of three participators. 展开更多
关键词 entangled state representation continuous variable quantum teleportation
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Non-Noether Conserved Quantity for Relativistic Nonholonomic System with Variable Mass 被引量:1
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作者 QIAOYong-Fen LIRen-Jie MAYong-Sheng 《Communications in Theoretical Physics》 SCIE CAS CSCD 2005年第2期197-200,共4页
Using form invariance under special infinitesimal transformations in which time is not variable, the non-Noether conserved quantity of the relativistic nonholonomic system with variable mass is studied. The differenti... Using form invariance under special infinitesimal transformations in which time is not variable, the non-Noether conserved quantity of the relativistic nonholonomic system with variable mass is studied. The differential equations of motion of the system are established. The definition and criterion of the form invariance of the system under infinitesimal transformations are studied. The necessary and sufficient. condition under which the form invariance is a Lie symmetry is given. The condition under which the form invariance can be led to a non-Noether. conserved quantity and the form of the conserved quantity are obtained. Finally, an example is given to illustrate the application of the result. 展开更多
关键词 analytical mechanics RELATIVITY nonholonomic system variable mass non-Noether conserved quantity
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Quantum Entropy of Black Hole with Internal Global Monopole 被引量:4
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作者 HANYi-Wen YANGShu-Zheng LIUWen-Biao 《Communications in Theoretical Physics》 SCIE CAS CSCD 2005年第2期382-384,共3页
Using the generalized uncertainty relation, the new equation of state density is obtained, and then the entropy of black hole with an internal global monopole is discussed. The divergence that appears in black hole en... Using the generalized uncertainty relation, the new equation of state density is obtained, and then the entropy of black hole with an internal global monopole is discussed. The divergence that appears in black hole entropy calculation through original brick-wall model is overcome. The result of the direct proportion between black hole entropy and its event horizon area is drawn and given. The result shows that the black hole entropy must be the entropy of quantum state near the event horizon. 展开更多
关键词 generalized uncertainty relation state density quantum entropy black hole
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Quality Characteristics Distribution and Its Simulation Based on Asymmetric Tolerances 被引量:1
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作者 祝伟 李元生 《Journal of China University of Mining and Technology》 2003年第2期223-225,共3页
The application of normal distribution for quality characteristics has its limits on the condition that specification interval is asymmetric. In this paper, the compound normal distribution N(L,σ12,σ22) was proposed... The application of normal distribution for quality characteristics has its limits on the condition that specification interval is asymmetric. In this paper, the compound normal distribution N(L,σ12,σ22) was proposed and simulated, the property of the parameters Lσ1 and σ2 was studied. The distribution was further applied toangle quality process control. 展开更多
关键词 specification interval asymmetric tolerance quality characteristics SIMULATION
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Fluid–solid coupling analysis of rock pillar stability for concealed karst cave ahead of a roadway based on catastrophic theory 被引量:9
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作者 Zhao Yanlin Peng Qingyang +2 位作者 Wan Wen Wang Weijun Chen Bin 《International Journal of Mining Science and Technology》 SCIE EI 2014年第6期737-745,共9页
In order to study the mechanism of water inrush from a concealed, confined karst cave, we established a fluid–solid coupling model of water inrush from a concealed karst cave ahead of a roadway and a strength reducti... In order to study the mechanism of water inrush from a concealed, confined karst cave, we established a fluid–solid coupling model of water inrush from a concealed karst cave ahead of a roadway and a strength reduction method in a rock pillar for preventing water inrush based on catastrophic theory. Fluid–solid coupling effects and safety margins in a rock pillar were studied. Analysis shows that rock pillar instability, exerted by disturbance stress and seepage stress, is the process of rock pillar catastrophic destabilization induced by nonlinear extension of plastic zones in the rock pillar. Seepage flow emerges in the rock pillar for preventing water inrush, accompanied by mechanical instability of the rock pillar. Taking the accident of a confined karst cave water-inrush of Qiyi Mine as an example, by studying the safety factor of the rock pillar and the relationship between karst cave water pressure and thickness of the rock pillar,it is proposed that rock pillar thickness with a safety factor equal to 1.5 is regarded as the calculated safety thickness of the rock pillar, which should be equal to the sum of the blasthole depth, blasting disturbance depth and the calculated safety thickness of the rock pillar. The cause of the karst water inrush at Qiyi Mine is that the rock pillar was so small that it did not possess a safety margin. Combining fluid–solid coupling theory, catastrophic theory and strength reduction method to study the nonlinear mechanical response of complicated rock engineering, new avenues for quantitative analysis of rock engineering stability evaluation should be forthcoming. 展开更多
关键词 Rock mechanics Catastrophic theory Shear strength reduction method Karst water inrush Safety factor
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Parametric Instability Analysis of Deepwater Top-Tensioned Risers Considering Variable Tension Along the Length 被引量:1
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作者 ZHANG Jie TANG Yougang 《Journal of Ocean University of China》 SCIE CAS 2015年第1期59-64,共6页
Parametric instability of a riser is caused by fluctuation of its tension in time due to the heave motion of floating platform. Many studies have tackled the problem of parametric instability of a riser with constant ... Parametric instability of a riser is caused by fluctuation of its tension in time due to the heave motion of floating platform. Many studies have tackled the problem of parametric instability of a riser with constant tension. However, tension in the riser actually varies linearly from the top to the bottom due to the effect of gravity. This paper presents the parametric instability analysis of deepwater top-tensioned risers(TTR) considering the linearly varying tension along the length. Firstly, the governing equation of transverse motion of TTR under parametric excitation is established. This equation is reduced to a system of ordinary differential equations by using the Galerkin method. Then the parametric instability of TTR for three calculation models are investigated by applying the Floquet theory. The results show that the natural frequencies of TTR with variable tension are evidently reduced, the parametric instability zones are significantly increased and the maximum allowable amplitude of platform heave is much smaller under the same damping; The nodes and antinodes of mode shape are no longer uniformly distributed along the axial direction and the amplitude also changes with depth, which leads to coupling between the modes. The combination resonance phenomenon occurs as a result of mode coupling, which causes more serious damage. 展开更多
关键词 deepwater risers parametric instability variable tension mode coupling
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Appointment scheduling with customer impatience based on operating cost model 被引量:1
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作者 Song Minshan Zhang Yulin 《Journal of Southeast University(English Edition)》 EI CAS 2019年第2期252-256,共5页
An appointment scheduling problem is studied with the consideration of customer impatience.On the assumption that both the time of leaving queue and the time of service are exponentially distributed,in order to minimi... An appointment scheduling problem is studied with the consideration of customer impatience.On the assumption that both the time of leaving queue and the time of service are exponentially distributed,in order to minimize the joint cost,the optimal appointment schedule of the fixed number of customers is studied.The joint cost function is composed of customers expected delay time and service availability time.The expected delay time of each customer in the queue is recursively computed in terms of customer interarrival time.Furthermore,the effect of impatience on the optimal schedule as well as the total operating cost is studied.The results show that as the impatience rate increases,the optimal interarrival time becomes shorter and the interarrival time of the last few customers gradually approaches that of the customers in the middle.In addition,impatient behaviors can increase the joint cost. 展开更多
关键词 APPOINTMENT customer impatience queueing theory single server
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Security analysis of access control model in hybrid cloud based on security entropy 被引量:2
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作者 车天伟 Ma Jianfeng +1 位作者 Li Na Wang Chao 《High Technology Letters》 EI CAS 2015年第2期200-204,共5页
To resolve the problem of quantitative analysis in hybrid cloud,a quantitative analysis method,which is based on the security entropy,is proposed.Firstly,according to the information theory,the security entropy is put... To resolve the problem of quantitative analysis in hybrid cloud,a quantitative analysis method,which is based on the security entropy,is proposed.Firstly,according to the information theory,the security entropy is put forward to calculate the uncertainty of the system' s determinations on the irregular access behaviors.Secondly,based on the security entropy,security theorems of hybrid cloud are defined.Finally,typical access control models are analyzed by the method,the method's practicability is validated,and security and applicability of these models are compared.Simulation results prove that the proposed method is suitable for the security quantitative analysis of the access control model and evaluation to access control capability in hybrid cloud. 展开更多
关键词 hybrid cloud security entropy classificatory access control model directly unauthorized access right about access indirectly unauthorized access
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Sign-invariant and Explicit Solutions of Nonlinear Reaction-Diffusion Systems 被引量:1
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作者 ZHU Xiao-Ning ZHANG Shun-Li 《Communications in Theoretical Physics》 SCIE CAS CSCD 2008年第6期1361-1364,共4页
Using the sign-invariant theory, we study the nonlinear reaction-diffusion systems. We also obtain some new explicit solutions to the nonlinear resulting systems.
关键词 sign-invariant theory nonlinear reaction-diffusion system explicit solutions
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Delay-dependent robust control for uncertain discrete singular systems with time-varying delay 被引量:2
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作者 Hui-jiao WANG Xiao-dong ZHAO +1 位作者 An-ke XUE Ren-quan LU 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2008年第8期1034-1042,共9页
The design problem of delay-dependent robust control for uncertain discrete singular systems with time-varying delay is addressed in this paper. The uncertainty is assumed to be norm-bounded. By establishing a finite ... The design problem of delay-dependent robust control for uncertain discrete singular systems with time-varying delay is addressed in this paper. The uncertainty is assumed to be norm-bounded. By establishing a finite sum inequality based on quadratic terms, a new delay-dependent robust stability condition is derived and expressed in terms of linear matrix inequalities (LMIs). A suitable robust state feedback control law is presented, which guarantees that the resultant closed-loop system is regular, causal and stable for all admissible uncertainties. Numerical examples are given to demonstrate the applicability of the proposed method. 展开更多
关键词 Uncertain discrete singular system Time-varying delay Robust control Linear matrix inequality (LMI)
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AN INTRUSION DETECTION SYSTEM BASED ON EVIDENCE THEORY AND ROUGH SET THEORY 被引量:2
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作者 Ye Qing Wu Xiaoping Zhang Changhong 《Journal of Electronics(China)》 2009年第6期777-781,共5页
In this paper,we propose a novel Intrusion Detection System (IDS) architecture utilizing both the evidence theory and Rough Set Theory (RST). Evidence theory is an effective tool in dealing with uncertainty question. ... In this paper,we propose a novel Intrusion Detection System (IDS) architecture utilizing both the evidence theory and Rough Set Theory (RST). Evidence theory is an effective tool in dealing with uncertainty question. It relies on the expert knowledge to provide evidences,needing the evidences to be independent,and this make it difficult in application. To solve this problem,a hybrid system of rough sets and evidence theory is proposed. Firstly,simplification are made based on Variable Precision Rough Set (VPRS) conditional entropy. Thus,the Basic Belief Assignment (BBA) for all evidences can be calculated. Secondly,Dempster’s rule of combination is used,and a decision-making is given. In the proposed approach,the difficulties in acquiring the BBAs are solved,the correlativity among the evidences is reduced and the subjectivity of evidences is weakened. An illustrative example in an intrusion detection shows that the two theories combination is feasible and effective. 展开更多
关键词 Intrusion Detection System (IDS) Evidence theory Rough Set Theory (RST)
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