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RECURRENT NEURAL NETWORK MODEL BASED ON PROJECTIVE OPERATOR AND ITS APPLICATION TO OPTIMIZATION PROBLEMS
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作者 马儒宁 陈天平 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2006年第4期543-554,共12页
The recurrent neural network (RNN) model based on projective operator was studied. Different from the former study, the value region of projective operator in the neural network in this paper is a general closed con... The recurrent neural network (RNN) model based on projective operator was studied. Different from the former study, the value region of projective operator in the neural network in this paper is a general closed convex subset of n-dimensional Euclidean space and it is not a compact convex set in general, that is, the value region of projective operator is probably unbounded. It was proved that the network has a global solution and its solution trajectory converges to some equilibrium set whenever objective function satisfies some conditions. After that, the model was applied to continuously differentiable optimization and nonlinear or implicit complementarity problems. In addition, simulation experiments confirm the efficiency of the RNN. 展开更多
关键词 recurrent neural network model projective operator global convergence OPTIMIZATION complementarity problems
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Multi-Parameter Design and Optimization for the Decomposition Projective Method and Its Applications
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作者 孙连友 洪伟 《Journal of Southeast University(English Edition)》 EI CAS 2002年第3期205-207,共3页
In order to solve the electromagnetic problems on the large multi branch domains, the decomposition projective method(DPM) is generalized for multi subspaces in this paper. Furthermore multi parameters are designed fo... In order to solve the electromagnetic problems on the large multi branch domains, the decomposition projective method(DPM) is generalized for multi subspaces in this paper. Furthermore multi parameters are designed for DPM, which is called the fast DPM(FDPM), and the convergence ratio of the above algorithm is greatly increased. The examples show that the iterative number of the FDPM with optimal parameters decreases much more, which is less than one third of the DPM iteration number. After studying the ... 展开更多
关键词 decomposition projective method projective operator cavity filter
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Accelerated Primal-Dual Projection Neurodynamic Approach With Time Scaling for Linear and Set Constrained Convex Optimization Problems
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作者 You Zhao Xing He +1 位作者 Mingliang Zhou Tingwen Huang 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2024年第6期1485-1498,共14页
The Nesterov accelerated dynamical approach serves as an essential tool for addressing convex optimization problems with accelerated convergence rates.Most previous studies in this field have primarily concentrated on... The Nesterov accelerated dynamical approach serves as an essential tool for addressing convex optimization problems with accelerated convergence rates.Most previous studies in this field have primarily concentrated on unconstrained smooth con-vex optimization problems.In this paper,on the basis of primal-dual dynamical approach,Nesterov accelerated dynamical approach,projection operator and directional gradient,we present two accelerated primal-dual projection neurodynamic approaches with time scaling to address convex optimization problems with smooth and nonsmooth objective functions subject to linear and set constraints,which consist of a second-order ODE(ordinary differential equation)or differential conclusion system for the primal variables and a first-order ODE for the dual vari-ables.By satisfying specific conditions for time scaling,we demonstrate that the proposed approaches have a faster conver-gence rate.This only requires assuming convexity of the objective function.We validate the effectiveness of our proposed two accel-erated primal-dual projection neurodynamic approaches through numerical experiments. 展开更多
关键词 Accelerated projection neurodynamic approach lin-ear and set constraints projection operators smooth and nonsmooth convex optimization time scaling.
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Projection Operator and Feynman Propagator for a Free Massive Particle of Arbitrary Spin
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作者 HUANGShi-Zhong ZHANGPeng-Fei +2 位作者 RUANTu-Nan ZHUYu-Can ZHENGZhi-Peng 《Communications in Theoretical Physics》 SCIE CAS CSCD 2004年第3期405-418,共14页
Based on the solution to the Bargmann Wigner equations, a direct derivation of the projection operator and Feynman propagator for a free massive particle of arbitrary spin is worked out. The projection operator constr... Based on the solution to the Bargmann Wigner equations, a direct derivation of the projection operator and Feynman propagator for a free massive particle of arbitrary spin is worked out. The projection operator constructed by Behrends and Fronsdal is re-deduced and confirmed, and simplified in the case of half-integral spin, the general commutation rules and Feynman propagator with additional non-covariant terms for a free massive particle with any spin are derived, and explicit expressions for the propagators for spins 3/2, 2, 5/2, 3, 7/2, and 4 are provided. 展开更多
关键词 free massive particle arbitrary spin projection operator Feynman propagator
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Projection Operator on Rational Noncommutative Orbifold T^2/Z_4
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作者 冯俊 杨战营 +2 位作者 张凯 侯伯宇 石康杰 《Communications in Theoretical Physics》 SCIE CAS CSCD 2011年第7期107-118,共12页
In this paper, we introduce the reduced matrix in kq representation and provide the reduced matrix elements of a projection operator P on the rational noncommutative orbifold T^2/Z_4.we give the closed form for the pr... In this paper, we introduce the reduced matrix in kq representation and provide the reduced matrix elements of a projection operator P on the rational noncommutative orbifold T^2/Z_4.we give the closed form for the projector by Jacobi elliptical functions. Since projectors correspond to soliton solutions of the field theory on the noncommutative orbifold, we thus present a corresponding soliton solution. 展开更多
关键词 SOLITON projection operator noncommutative orbifold T2/Z4
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SINGULAR INTEGRAL EQUATIONS WITHCOMPLEX TRANSLATIONS 被引量:1
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作者 杜金元 胡继承 《Acta Mathematica Scientia》 SCIE CSCD 1999年第4期469-480,共12页
In this paper, a class of singular integral equations with complex translations is discussed. By using the Plemelj projection method the authors reduce them to the boundary value problem of analytic functions in A(+)(... In this paper, a class of singular integral equations with complex translations is discussed. By using the Plemelj projection method the authors reduce them to the boundary value problem of analytic functions in A(+)(H) over cap(0) with upper translation and the boundary value problem of analytic functions in A-(H) over cap(0) with lower translation, which are solved here. 展开更多
关键词 singular integral equation singular integral operator singular projection operator upper translation lower translation
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Non-Markovian dynamics of a qubit in a reservoir: different solutions of non-Markovian master equation 被引量:1
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作者 丁邦福 王小云 +2 位作者 唐艳芳 米贤武 赵鹤平 《Chinese Physics B》 SCIE EI CAS CSCD 2011年第6期25-29,共5页
We present a non-Markovian master equation for a qubit interacting with a general reservoir, which is derived according to the Nakajima-Zwanzig and the time convolutionless projection operator technique. The non-Marko... We present a non-Markovian master equation for a qubit interacting with a general reservoir, which is derived according to the Nakajima-Zwanzig and the time convolutionless projection operator technique. The non-Markovian solutions and Markovian solution of dynamical decay of a qubit are compared. The results indicate the validity of non-Markovian approach in different coupling regimes and also show that the Markovian master equation may not precisely describe the dynamics of an open quantum system in some situation. The non-Markovian solutions may be effective for many qubits independently interacting with the heated reservoirs. 展开更多
关键词 Nakajima-Zwanzig and time convolutionless projection operator technique non- Markovian solutions Markovian solutions correlation function QUBIT
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Arnoldi Projection Fractional Tikhonov for Large Scale Ill-Posed Problems 被引量:1
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作者 Wang Zhengsheng Mu Liming +1 位作者 Liu Rongrong Xu Guili 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2018年第3期395-402,共8页
It is well known that Tikhonov regularization in standard form may determine approximate solutions that are too smooth for ill-posed problems,so fractional Tikhonov methods have been introduced to remedy this shortcom... It is well known that Tikhonov regularization in standard form may determine approximate solutions that are too smooth for ill-posed problems,so fractional Tikhonov methods have been introduced to remedy this shortcoming.And Tikhonov regularization for large-scale linear ill-posed problems is commonly implemented by determining apartial Arnoldi decomposition of the given matrix.In this paper,we propose a new method to compute an approximate solution of large scale linear discrete ill-posed problems which applies projection fractional Tikhonov regularization in Krylov subspace via Arnoldi process.The projection fractional Tikhonov regularization combines the fractional matrices and orthogonal projection operators.A suitable value of the regularization parameter is determined by the discrepancy principle.Numerical examples with application to image restoration are carried out to examine that the performance of the method. 展开更多
关键词 ill-posed problems fractional matrix Tikhonov regularization orthogonal projection operator image restoration
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A NOVEL DIRECTION OF ARRIVAL ESTIMATOR 被引量:1
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作者 ShaoChao LuGuangyue BaoZheng 《Journal of Electronics(China)》 2004年第2期97-103,共7页
A Direction Of Arrival(DOA) estimator based on the signal separation principle is introduced, and one of representative multidimensional estimators is established by introducing Matrix Operator projection signal steer... A Direction Of Arrival(DOA) estimator based on the signal separation principle is introduced, and one of representative multidimensional estimators is established by introducing Matrix Operator projection signal steering Vector Excision(MOVE) operation. Thanks to Alternating Separation (AS) technique, the multidimensional problem is transformed into a series of one-dimensional optimal ones. Furthermore, an equivalent simplified implementation of the AS is obtained. Finally the definiteness and uniqueness of the estimator are analyzed. 展开更多
关键词 Matrix operator projection signal steering Vector Excision(MOVE) estimator Alternating Separation(AS) algorithm Alternating projection algorithm
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Generalized Quantum Master Equation:A Tutorial Review and Recent Advances
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作者 Dominikus Brian Xiang Sun 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2021年第5期497-524,I0002,共29页
The generalized quantum master equation(GQME)provides a general and exact approach for simulating the reduced dynamics in open quantum systems where a quantum system is embedded in a quantum environment.Dynamics of op... The generalized quantum master equation(GQME)provides a general and exact approach for simulating the reduced dynamics in open quantum systems where a quantum system is embedded in a quantum environment.Dynamics of open quantum systems is important in excitation energy,charge,and quantum coherence transfer as well as reactive photochemistry.The system is usually chosen to be the interested degrees of freedom such as the electronicstates in light-harvesting molecules or tagged vibrational modes in a condensed-phase system.The environment is also called the bath,whose influence on the system has to be considered,and for instance can be described by the GQME formalisms using the projection operator technique.In this review,we provide a heuristic description of the development of two canonical forms of GQME,namely the time-convoluted Nakajima-Zwanzig form(NZ-GQME)and the time-convolutionless form(TCL-GQME).In the more popular NZ-GQME form,the memory kernel serves as the essential part that reflects the non-Markovian and non-perturbative effects,which gives formally exact dynamics of the reduced density matrix.We summarize several schemes to express the projection-based memory kernel of NZ-GQME in terms of projection-free time correlation function inputs that contain molecular information.In particular,the recently proposed modified GQME approach based on NZ-GQME partitions the Hamiltonian into a more general diagonal and off-diagonal parts.The projection-free inputs in the above-mentioned schemes expressed in terms of different system-dependent time correlation functions can be calculated via numerically exact or approximate dynamical methods.We hope this contribution would help lower the barrier of understanding the theoretical pillars for GQME-based quantum dynamics methods and also envisage that their combination with the quantum computing techniques will pave the way for solving complex problems related to quantum dynamics and quantum information that are currently intractable even with today’s state-of-the-art classical supercomputers. 展开更多
关键词 Open quantum system Generalized quantum master equation Quantum dynamics Projection operator Nakajima-Zwanzig Quantum computing Reduced density matrix System-bath
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ERROR ESTIMATE FOR INFLUENCE OF MODEL REDUCTION OF NONLINEAR DISSIPATIVE AUTONOMOUS DYNAMICAL SYSTEM ON LONG-TERM BEHAVIOURS
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作者 张家忠 刘雁 陈党民 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2005年第7期938-943,共6页
From viewpoint of nonlinear dynamics, the model reduction and its influence on the long-term behaviours of a class of nonlinear dissipative autonomous dynamical system with higher dimension are investigated theoretica... From viewpoint of nonlinear dynamics, the model reduction and its influence on the long-term behaviours of a class of nonlinear dissipative autonomous dynamical system with higher dimension are investigated theoretically under some assumptions. The system is analyzed in the state space with an introduction of a distance definition which can be used to describe the distance between the full system and the reduced system, and the solution of the full system is then projected onto the complete space spanned by the eigenvectors of the linear operator of the governing equations. As a result, the influence of mode series truncation on the long-term behaviours and the error estimate are derived, showing that the error is dependent on the first products of frequencies and damping ratios in the subspace spanned by the eigenvectors with higher modal damping. Furthermore, the fundamental understanding for the topological change of the solution due to the application of different model reduction is interpreted in a mathematically precise way, using the qualitative theory of nonlinear dynamics. 展开更多
关键词 nonlinear dynamical system dissipative system projection operator long-term behaviour
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Non-Markovian dynamics of two non-coupled qubits interacting with two separate reservoirs with different spectral densities
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作者 王小云 丁邦福 赵鹤平 《Chinese Physics B》 SCIE EI CAS CSCD 2013年第4期128-132,共5页
The dynamics of two non-coupled qubits independently interacting with their reservoirs is solved by the time convolutionless projection operator method. We study two-qubit quantum correlation dynamics for two differen... The dynamics of two non-coupled qubits independently interacting with their reservoirs is solved by the time convolutionless projection operator method. We study two-qubit quantum correlation dynamics for two different types of spectral densities, which are a Lorentzian distribution and an Ohmic spectral density with a Lorentzian–Drude cutoff function. For two qubits initially prepared in the initial Bell state, quantum discord can keep longer time and reach larger values in nonMarkovian reservoirs for the first spectral distribution or by reducing the cutoff frequency for the second case. For the initial Bell-like state, the dynamic behaviors of quantum discord and entanglement are compared. The results show that a long time of quantum correlation can be obtained by adjusting some parameters in experiment and further confirm that the discord can capture quantum correlation in addition to entanglement. 展开更多
关键词 Lorentzian and Ohmic spectral densities the time convolution-less projection operator method non-Markovian and Markovian regime quantum discord and entanglement
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Operation safety risk analysis method of hydropower project considering time-dependent effect
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作者 Zhang Sherong Yan Lei 《Engineering Sciences》 EI 2012年第5期45-50,共6页
In order to consider the time-dependent characteristic of risk factors of hydropower project,the method of stochastic process simulating structure resistance and load effect is adopted.On the basis of analyzing the st... In order to consider the time-dependent characteristic of risk factors of hydropower project,the method of stochastic process simulating structure resistance and load effect is adopted.On the basis of analyzing the structure characteristics and mode of operation,the operation safety risk rate assessment model of hydropower project is established on the comprehensive application of the improved analytic hierarchy process,the time-dependent reliability theory and the risk rate threshold.A scheme to demonstrate the time-dependent risk rate assessment method for an example of the earth-rock dam is particularly implemented by the proposed approach.The example shows that operation safety risk rate is closely related to both the service period and design standard;considering the effect of time-dependent,the risk rate increases with time and the intersection of them reflects the technical service life of structures.It could provide scientific basis for the operation safety and risk decision of the hydropower project by predicting the trend of risk rate via this model. 展开更多
关键词 operation safety of hydropower project risk analysis risk rate assessment time-dependent reliability improved analytic hierarchy process
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Jilin Tongyu Wind Power Farm 2nd Phase Project put into operation
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《Electricity》 2001年第1期51-51,共1页
关键词 WIND PROJECT Jilin Tongyu Wind Power Farm 2nd Phase Project put into operation
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The Second-Order Differential Equation System with the Feedback Controls for Solving Convex Programming
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作者 Xingxu Chen Li Wang +1 位作者 Juhe Sun Yanhong Yuan 《Open Journal of Applied Sciences》 2022年第6期977-989,共13页
In this paper, we establish the second-order differential equation system with the feedback controls for solving the problem of convex programming. Using Lagrange function and projection operator, the equivalent opera... In this paper, we establish the second-order differential equation system with the feedback controls for solving the problem of convex programming. Using Lagrange function and projection operator, the equivalent operator equations for the convex programming problems under the certain conditions are obtained. Then a second-order differential equation system with the feedback controls is constructed on the basis of operator equation. We prove that any accumulation point of the trajectory of the second-order differential equation system with the feedback controls is a solution to the convex programming problem. In the end, two examples using this differential equation system are solved. The numerical results are reported to verify the effectiveness of the second-order differential equation system with the feedback controls for solving the convex programming problem. 展开更多
关键词 Convex Programming Lagrange Function Projection operator Second-Order Differential Equation
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Research on Safety Risk Assessment Method for Large Scale Field Operation Project
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作者 JIANG Wei-yang ZHAO Man-yun +1 位作者 ZHANG Lian SONG Wei-dong 《International Journal of Plant Engineering and Management》 2016年第2期65-74,共10页
By applying man-machine-environment system engineering theory, safety risks on large scale field operation project have been evaluated in this article. The factors concerning with the man, machine and environment in s... By applying man-machine-environment system engineering theory, safety risks on large scale field operation project have been evaluated in this article. The factors concerning with the man, machine and environment in system were proposed separately. The value for lowest indexs was determined by decision-making of expert group. The weights were calculated based on AHP, and then safety risk assessment in different layers was made. The results show that the assessment method is reasonable, and it is significant for large scale field operation project safety managerment. 展开更多
关键词 large scale field operation project safety risk assessment man-machine-environment system
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Risk Management and Operation Strategies of Chinese Overseas Risk Exploration Projects
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作者 Li Juntin Li Song Wen Zhifeng 《China Oil & Gas》 CAS 2013年第4期41-47,共7页
Currently,the investment of oil and gas industry is still facing an unfavorable environment,in which,instable factors,such as financial crisis,terrorist,religious conflicts and rigorous environmental regulations,keep ... Currently,the investment of oil and gas industry is still facing an unfavorable environment,in which,instable factors,such as financial crisis,terrorist,religious conflicts and rigorous environmental regulations,keep mucking up the business all around the world.Meanwhile,China’s rapid energy consumption growth boosted by a booming economy has put the country to rely heavily on exported oil.It is therefore extremely urgent to expand and diversify petroleum supply channel in consideration of the country’s energy security.As the world’s economy has been slowly recovering from the slump and 展开更多
关键词 HSE Risk Management and Operation Strategies of Chinese Overseas Risk Exploration Projects
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West-East Gas Project Operational This Year
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《Journal of Natural Gas Chemistry》 CAS CSCD 2004年第4期248-248,共1页
China’s massive project to transfer natural gas from the Tarim Basin of Xinjiang Uygur autonomous region all the way to the coastal metropolis of Shanghai in the east will go into commercial operation on Dec. 30, acc... China’s massive project to transfer natural gas from the Tarim Basin of Xinjiang Uygur autonomous region all the way to the coastal metropolis of Shanghai in the east will go into commercial operation on Dec. 30, according to the National Development and Reform Commission (NDRC). 展开更多
关键词 PROJECT West-East Gas Project Operational This Year
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The Connection Between the Metric and Generalized Projection Operators in Banach Spaces 被引量:4
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作者 Yakov ALBER Jin Lu LI 《Acta Mathematica Sinica,English Series》 SCIE CSCD 2007年第6期1109-1120,共12页
In this paper we study the connection between the metric projection operator PK : B →K, where B is a reflexive Banach space with dual space B^* and K is a non-empty closed convex subset of B, and the generalized pr... In this paper we study the connection between the metric projection operator PK : B →K, where B is a reflexive Banach space with dual space B^* and K is a non-empty closed convex subset of B, and the generalized projection operators ∏K : B → K and πK : B^* → K. We also present some results in non-reflexive Banach spaces. 展开更多
关键词 Banach spaces normalized duality mappings metric and generalized projection operators variational inequalities minimization problems closed and convex subsets and cones
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Some Applications of Projection Operators in Wavelets 被引量:5
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作者 Han Bin Institute of Mathematics Academia Sinica Beijing,100080 China 《Acta Mathematica Sinica,English Series》 SCIE CSCD 1995年第1期105-112,共8页
By rewriting the projection operator P<sub>0</sub> in wavelets in another formula,we obtain a characterization of dim J<sub>V</sub><sub>0</sub>(x)where V<sub>0</sub> i... By rewriting the projection operator P<sub>0</sub> in wavelets in another formula,we obtain a characterization of dim J<sub>V</sub><sub>0</sub>(x)where V<sub>0</sub> is a Γ-shift-invariant subspace of L<sup>2</sup>(R<sup>n</sup>)derived from a dual wavelet basis and prove that there does not exist a wavelet function ψ ∈ L<sup>2</sup>(R)such that (?)has compact support and ∪<sub>k</sub>∈ZZ(supp■+4πk)=R up to a zero subset of R. 展开更多
关键词 Some Applications of Projection operators in Wavelets
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