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Wigner function of optical cumulant operator and its dissipation in thermo-entangled state representation
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作者 张科 李兰兰 范洪义 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第6期205-210,共6页
To conveniently calculate the Wigner function of the optical cumulant operator and its dissipation evolution in a thermal environment, in this paper, the thermo-entangled state representation is introduced to derive t... To conveniently calculate the Wigner function of the optical cumulant operator and its dissipation evolution in a thermal environment, in this paper, the thermo-entangled state representation is introduced to derive the general evolution formula of the Wigner function, and its relation to Weyl correspondence is also discussed. The method of integration within the ordered product of operators is essential to our discussion. 展开更多
关键词 Wigner function optical cumulant operator dissipation evolution thermo-entangled state representation integration within ordered product of operators
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Chaos game representation of functional protein sequences,and simulation and multifractal analysis of induced measures 被引量:1
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作者 喻祖国 肖前军 +2 位作者 石龙 余君武 Vo Anh 《Chinese Physics B》 SCIE EI CAS CSCD 2010年第6期556-568,共13页
Investigating the biological function of proteins is a key aspect of protein studies. Bioinformatic methods become important for studying the biological function of proteins. In this paper, we first give the chaos gam... Investigating the biological function of proteins is a key aspect of protein studies. Bioinformatic methods become important for studying the biological function of proteins. In this paper, we first give the chaos game representation (CGR) of randomly-linked functional protein sequences, then propose the use of the recurrent iterated function systems (RIFS) in fractal theory to simulate the measure based on their chaos game representations. This method helps to extract some features of functional protein sequences, and furthermore the biological functions of these proteins. Then multifractal analysis of the measures based on the CGRs of randomly-linked functional protein sequences are performed. We find that the CGRs have clear fractal patterns. The numerical results show that the RIFS can simulate the measure based on the CGR very well. The relative standard error and the estimated probability matrix in the RIFS do not depend on the order to link the functional protein sequences. The estimated probability matrices in the RIFS with different biological functions are evidently different. Hence the estimated probability matrices in the RIFS can be used to characterise the difference among linked functional protein sequences with different biological functions. From the values of the Dq curves, one sees that these functional protein sequences are not completely random. The Dq of all linked functional proteins studied are multifractal-like and sufficiently smooth for the Cq (analogous to specific heat) curves to be meaningful. Furthermore, the Dq curves of the measure μ based on their CCRs for different orders to link the functional protein sequences are almost identical if q 〉 0. Finally, the Ca curves of all linked functional proteins resemble a classical phase transition at a critical point. 展开更多
关键词 chaos game representation recurrent iterated function systems functional proteins multifractal analysis
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Oxygen Reduction Reaction Activity of Fe-based Dual-Atom Catalysts with Different Local Configurations via Graph Neural Representation
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作者 Xueqian Xia Zengying Ma Yucheng Huang 《Chinese Journal of Chemical Physics》 SCIE EI CAS CSCD 2024年第5期599-604,I0038-I0040,I0099,共10页
The performance of proton exchange membrane fuel cells depends heavily on the oxygen reduction reaction(ORR)at the cathode,for which platinum-based catalysts are currently the standard.The high cost and limited availa... The performance of proton exchange membrane fuel cells depends heavily on the oxygen reduction reaction(ORR)at the cathode,for which platinum-based catalysts are currently the standard.The high cost and limited availability of platinum have driven the search for alternative catalysts.While FeN4 single-atom catalysts have shown promising potential,their ORR activity needs to be further enhanced.In contrast,dual-atom catalysts(DACs)offer not only higher metal loading but also the ability to break the ORR scaling relations.However,the diverse local structures and tunable coordination environments of DACs create a vast chemical space,making large-scale computational screening challenging.In this study,we developed a graph neural network(GNN)-based framework to predict the ORR activity of Fe-based DACs,effectively addressing the challenges posed by variations in local catalyst structures.Our model,trained on a dataset of 180 catalysts,accurately predicted the Gibbs free energy of ORR intermediates and overpotentials,and identified 32 DACs with superior catalytic activity compared to FeN4 SAC.This approach not only advances the design of high-performance DACs,but also offers a powerful computational tool that can significantly reduce the time and cost of catalyst development,thereby accelerating the commercialization of fuel cell technologies. 展开更多
关键词 Oxygen reduction reaction Dual-atom catalyst Graph neural representation Density functional theory Artificial intelligence
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Relationship Between Wave Function and Corresponding Wigner Function Studied in Entangled State Representation 被引量:2
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作者 XU Xing-Lei LI Hong-Qi FAN Hong-Yi 《Communications in Theoretical Physics》 SCIE CAS CSCD 2008年第5期1159-1162,共4页
By using the explicit form of the entangled Wigner operator and the entangled state representation we derive the relationship between wave function and corresponding Wigner function for bipartite entangled systems. Th... By using the explicit form of the entangled Wigner operator and the entangled state representation we derive the relationship between wave function and corresponding Wigner function for bipartite entangled systems. The technique of integration within an ordered product (IWOP) of operators is employed in our discussions. 展开更多
关键词 Wigner function entangled state representation IWOP technique
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Simulation for chaos game representation of genomes by recurrent iterated function systems 被引量:1
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作者 Zu-Guo Yu Long Shi +1 位作者 Qian-Jun Xiao Vo Anh 《Journal of Biomedical Science and Engineering》 2008年第1期44-51,共8页
Chaos game representation (CGR) of DNA sequences and linked protein sequences from genomes was proposed by Jeffrey (1990) and Yu et al. (2004), respectively. In this paper, we consider the CGR of three kinds of sequen... Chaos game representation (CGR) of DNA sequences and linked protein sequences from genomes was proposed by Jeffrey (1990) and Yu et al. (2004), respectively. In this paper, we consider the CGR of three kinds of sequences from complete genomes: whole genome DNA sequences, linked coding DNA sequences and linked protein sequences. Some fractal patterns are found in these CGRs. A recurrent iterated function systems (RIFS) model is proposed to simulate the CGRs of these sequences from genomes and their induced measures. Numerical results on 50 genomes show that the RIFS model can simulate very well the CGRs and their induced measures. The parameters estimated in the RIFS model reflect information on species classification. 展开更多
关键词 GENOMES CHAOS GAME representation RECURRENT ITERATED function systems.
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From the Green's Function in Tight-Binding Representation to Interatomic Many-body Potentials 被引量:1
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作者 Shaojun LIU(Department of physics, Beijing Normal University, Beijing 100875, China)Xiaobo WEI(Department of Physics, Liuzhou College of Education, Liuzhou 545005, China)Zhaodou CHEN Jun CAI and Benkun MA(Department of Physics, Beijing Normal University, 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 1999年第4期315-319,共5页
In this paper, we deduce the analytical form of many-body interatomic potentials based on the Green's function in tight-binding representation. The many-body potentials are expressed as the functions of the hoppin... In this paper, we deduce the analytical form of many-body interatomic potentials based on the Green's function in tight-binding representation. The many-body potentials are expressed as the functions of the hopping integrals which are the physical origin of cohesion of atoms. For thesimple case of s-valent system, the inversion of the many-body potentials are discussed in detail by using the lattice inversion method. 展开更多
关键词 Rev Li CHEN From the Green’s function in Tight-Binding representation to Interatomic Many-body Potentials body
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Relations Between Characteristic Function,Positive P-Representation and Coherent Thermal State 被引量:1
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作者 FAN Hong-Yi XU Xing-Lei Department of Material Science and Engineering,University of Science and Technology of China,Hefei 230026,China2 Department of Physics,Shanghai Jiao Tong University,Shanghai 200030,China3 Department of Physics,Heze University,Heze 274015,China 《Communications in Theoretical Physics》 SCIE CAS CSCD 2007年第7期67-70,共4页
We employ the coherent thermal states(a kind of entangled states)in thermal field dynamics to establisha complete entangled state formalism expressing pseudo-classical representations of density operator for light fie... We employ the coherent thermal states(a kind of entangled states)in thermal field dynamics to establisha complete entangled state formalism expressing pseudo-classical representations of density operator for light field.Especially,the relationship between the coherent thermal state and the characteristic function and the positive Prepresentation in quantum optics theory are obtained. 展开更多
关键词 coherent thermal state characteristic function positive P-representation
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Application of Angular Momentum Theory to Constructing Basis Functions of Irreducible Representations of Icosahedral Group
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作者 LIAn-yong 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2004年第2期166-175,共10页
A new method based on angular momentum theory was proposed to construct the basis functions of the irreducible representations(IRs) of point groups. The transformation coefficients, i. e., coefficients S, are the com... A new method based on angular momentum theory was proposed to construct the basis functions of the irreducible representations(IRs) of point groups. The transformation coefficients, i. e., coefficients S, are the components of the eigenvectors of some Hermitian matrices, and can be made as real numbers for all pure rotation point groups. The general formula for coefficient S was deduced, and applied to constructing the basis functions of single-valued irreducible representations of icosahedral group from the spherical harmonics with angular momentum j≤7. 展开更多
关键词 Irreducible representation Basis function I group Angular momentum
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STRONG REPRESENTATIONS OF THE SURVIVAL FUNCTION ESTIMATOR ON INCREASING SETS FOR TRUNCATED AND CENSORED DATA
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作者 孙六全 郑忠国 《Acta Mathematica Scientia》 SCIE CSCD 1999年第3期251-260,共10页
In this paper, based on random left truncated and right censored data, the authors derive strong representations of the cumulative hazard function estimator and the product-limit estimator of the survival function. wh... In this paper, based on random left truncated and right censored data, the authors derive strong representations of the cumulative hazard function estimator and the product-limit estimator of the survival function. which are valid up to a given order statistic of the observations. A precise bound for the errors is obtained which only depends on the index of the last order statistic to be included. 展开更多
关键词 truncated and censored data cumulative hazard function product-limit estimator strong representations
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Wave function for the squeezed atomic coherent state in entangled state representation and some of its applications
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作者 王继锁 孟祥国 梁宝龙 《Chinese Physics B》 SCIE EI CAS CSCD 2010年第1期326-331,共6页
Based on the Einstein, Podolsky, and Rosen (EPR) entangled state representation, this paper introduces the wave function for the squeezed atomic coherent state (SACS), which turns out to be just proportional to a ... Based on the Einstein, Podolsky, and Rosen (EPR) entangled state representation, this paper introduces the wave function for the squeezed atomic coherent state (SACS), which turns out to be just proportional to a single-variable ordinary Hermite polynomial of order 2j. As important applications of the wave function, the Wigner function of the SACS and its marginal distribution are obtained and the eigenproblems of some Hamiltonians for the generalized angular momentum system are solved. 展开更多
关键词 squeezed atomic coherent state entangled state representation Wigner function eigen- value and eigenstate
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Some New Properties of Wigner Function Studied in Entangled State Representation
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作者 范洪义 《Communications in Theoretical Physics》 SCIE CAS CSCD 2010年第8期241-243,共3页
Based on the Wigner operator in the entangled state representation we study some new important propertiesof Wigner function for bipartite entangled systems,such as size of an entangled state,upper bound of Wigner func... Based on the Wigner operator in the entangled state representation we study some new important propertiesof Wigner function for bipartite entangled systems,such as size of an entangled state,upper bound of Wigner functions,etc.These discussions demonstrate the beauty and elegance of the entangled state representation. 展开更多
关键词 Wigner function entangled state representation Wigner operator
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Study Hankel Transforms and Properties of Bessel Function via Entangled State Representation Transformation in Quantum Mechanics
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作者 FAN Hong-Yi WANG Yong 《Communications in Theoretical Physics》 SCIE CAS CSCD 2006年第5期819-824,共6页
In Phys. Lett. A 313 (2003) 343 we have found that the self-recipràcal Hankel transformation (HT) is embodied in quantum mechanics by a transform between two entangled state representations of continuum varia... In Phys. Lett. A 313 (2003) 343 we have found that the self-recipràcal Hankel transformation (HT) is embodied in quantum mechanics by a transform between two entangled state representations of continuum variables. In this work we study Hankel transforms and properties of Bessel function via entangled state representations' transformation in quantum mechanics. 展开更多
关键词 entangled state representation Hankel transform Bessel function
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An elementary proof for the representation theorem of analytic isotropic tensor functions of a second-order tensor
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作者 Tianbo WANG Dinglin YANG +1 位作者 Chen LI Diwei SHI 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2021年第5期747-754,共8页
Based on the Cayley-Hamilton theorem and fixed-point method,we provide an elementary proof for the representation theorem of analytic isotropic tensor functions of a second-order tensor in a three-dimensional(3D)inner... Based on the Cayley-Hamilton theorem and fixed-point method,we provide an elementary proof for the representation theorem of analytic isotropic tensor functions of a second-order tensor in a three-dimensional(3D)inner-product space,which avoids introducing the generating function and Taylor series expansion.The proof is also extended to any finite-dimensional inner-product space. 展开更多
关键词 representation theorem analytic tensor function fixed-point method
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Series Representation of Power Function
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作者 Petro Kolosov 《Applied Mathematics》 2016年第3期327-333,共7页
This paper presents the way to make expansion for the next form function: to the numerical series. The most widely used methods to solve this problem are Newtons Binomial Theorem and Fundamental Theorem of Calculus (t... This paper presents the way to make expansion for the next form function: to the numerical series. The most widely used methods to solve this problem are Newtons Binomial Theorem and Fundamental Theorem of Calculus (that is, derivative and integral are inverse operators). The paper provides the other kind of solution, except above described theorems. 展开更多
关键词 Series Expansion Series representation Binomial Theorem Power function Cube Number Number to Power
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Generation of endurance time excitation functions using spectral representation method
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作者 Parsa Parvanehro Mohammad Safi 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2023年第2期441-452,共12页
In this study,application of the spectral representation method for generation of endurance time excitation functions is introduced.Using this method,the intensifying acceleration time series is generated so that its ... In this study,application of the spectral representation method for generation of endurance time excitation functions is introduced.Using this method,the intensifying acceleration time series is generated so that its acceleration response spectrum in any desired time duration is compatible with a time-scaled predefined acceleration response spectrum.For this purpose,simulated stationary acceleration time series is multiplied by the time dependent linear modulation function,then using a simple iterative scheme,it is forced to match a target acceleration response spectrum.It is shown that the generated samples have excellent conformity in low frequency,which is useful for nonlinear endurance time analysis.In the second part of this study,it is shown that this procedure can be extended to generate a set of spatially correlated endurance time excitation functions.This makes it possible to assess the performance of long structures under multi-support seismic excitation using endurance time analysis. 展开更多
关键词 endurance time analysis endurance time excitation functions spatial variation of seismic ground motions multi-support excitation spectral representation method
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THE PROBABILISTIC REPRESENTATION FORMULAE FOR COSINE OPERATOR FUNCTIONS
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作者 周密 陈文忠 《Analysis in Theory and Applications》 1993年第1期42-52,共11页
In this paper we obtained general representation formulae for strongly continuous cosine operator functions via probabilistic approach,which include Webb's[1]and Shaw's[2]formulae and some new one as special c... In this paper we obtained general representation formulae for strongly continuous cosine operator functions via probabilistic approach,which include Webb's[1]and Shaw's[2]formulae and some new one as special cases.We also give the quantitative estimations for the general formulae. 展开更多
关键词 TH THE PROBABILISTIC representation FORMULAE FOR COSINE OPERATOR functionS
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Applications of Fractional Lower Order Time-frequency Representation to Machine Bearing Fault Diagnosis 被引量:5
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作者 Junbo Long Haibin Wang +1 位作者 Peng Li Hongshe Fan 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2017年第4期734-750,共17页
The machinery fault signal is a typical non-Gaussian and non-stationary process. The fault signal can be described by SaS distribution model because of the presence of impulses.Time-frequency distribution is a useful ... The machinery fault signal is a typical non-Gaussian and non-stationary process. The fault signal can be described by SaS distribution model because of the presence of impulses.Time-frequency distribution is a useful tool to extract helpful information of the machinery fault signal. Various fractional lower order(FLO) time-frequency distribution methods have been proposed based on fractional lower order statistics, which include fractional lower order short time Fourier transform(FLO-STFT), fractional lower order Wigner-Ville distributions(FLO-WVDs), fractional lower order Cohen class time-frequency distributions(FLO-CDs), fractional lower order adaptive kernel time-frequency distributions(FLO-AKDs) and adaptive fractional lower order time-frequency auto-regressive moving average(FLO-TFARMA) model time-frequency representation method.The methods and the exiting methods based on second order statistics in SaS distribution environments are compared, simulation results show that the new methods have better performances than the existing methods. The advantages and disadvantages of the improved time-frequency methods have been summarized.Last, the new methods are applied to analyze the outer race fault signals, the results illustrate their good performances. 展开更多
关键词 adaptive function Alpha stable distribution auto-regressive(AR) model non-stationary signal parameter estimation time frequency representation
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Chaos game representation walk model for the protein sequences 被引量:3
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作者 高洁 蒋丽丽 徐振源 《Chinese Physics B》 SCIE EI CAS CSCD 2009年第10期4571-4579,共9页
A new chaos game representation of protein sequences based on the detailed hydrophobic-hydrophilic (HP) model has been proposed by Yu et al (Physica A 337(2004) 171). A CGR-walk model is proposed based on the ne... A new chaos game representation of protein sequences based on the detailed hydrophobic-hydrophilic (HP) model has been proposed by Yu et al (Physica A 337(2004) 171). A CGR-walk model is proposed based on the new CGR coordinates for the protein sequences from complete genomes in the present paper. The new CCR coordinates based on the detailed HP model are converted into a time series, and a long-memory ARFIMA(p, d, q) model is introduced into the protein sequence analysis. This model is applied to simulating real CCR-walk sequence data of twelve protein sequences. Remarkably long-range correlations are uncovered in the data and the results obtained from these models are reasonably consistent with those available from the ARFIMA(p, d, q) model. 展开更多
关键词 chaos game representation CGR-walk model protein sequence long-memory ARFIMA(p d q) model autocorrelation function
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The Leray-Stokes Type Integral Representation Formulas on the Analytic Varieties 被引量:1
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作者 CHEN Shu-jin 《Chinese Quarterly Journal of Mathematics》 2018年第4期395-416,共22页
The closure of the bounded domains D in Cnconsists of a chain of the slit spaces,and may be divided into two types. Based on the two types of bounded domains in C^n, firstly using different method and technique we der... The closure of the bounded domains D in Cnconsists of a chain of the slit spaces,and may be divided into two types. Based on the two types of bounded domains in C^n, firstly using different method and technique we derive the corresponding integral representation formulas of differentiable functions for complex n-m(0 ≤ m < n) dimensional analytic varieties in the two types of the bounded domains. Secondly we obtain the unified integral representation formulas of differentiable functions for complex n-m(0 ≤ m < n) dimensional analytic varieties in the general bounded domains. When functions are holomorphic, the integral formulas in this paper include formulas of Stout^([1]), Hatziafratis^([2]) and the author^([3]),and are the extension of all the integral representations for holomorphic functions in the existing papers to analytic varieties. In particular, when m = 0, firstly we gave the integral representation formulas of differentiable functions for the two types of bounded domains in C^n. Therefore they can make the concretion of Leray-Stokes formula. Secondly we obtain the unified integral representation formulas of differentiable functions for general bounded domains in C^n. So they can make the Leray-Stokes formula generalizations. 展开更多
关键词 Complex SUBMANIFOLD ANALYTIC VARIETIES Unified formula Extension DIFFERENTIABLE function Integral representation
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State Representation Methodology (SRM) for Bridge Condition Assessment in SHM 被引量:2
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《Journal of Civil Engineering and Architecture》 2012年第4期433-443,共11页
This paper introduces a new concept of "State Representation Methodology (SRM)" which is a kind of bridge condition assessment method for structural health monitoring system (SHM). There are many methods for sys... This paper introduces a new concept of "State Representation Methodology (SRM)" which is a kind of bridge condition assessment method for structural health monitoring system (SHM). There are many methods for system identification from the simplicity comparison of damage index to the complicated statistical pattern recognition algorithms in SHM. In these methods, modal analysis and parameters identification or many defined indices are common-used for extracting the dynamic or static characteristics of a system. However, there is a common problem: due to the complexity of a large size system with high-order nonlinear characteristics and severe environment interference, it is impossible to extract and quantify exactly these modal parameters or system parameters or indices as the feature vectors of a system in damage detection in an easy way. The SRM considered a more general theory for the non-parametric description of system state. 展开更多
关键词 BRIDGE damage detection system state representation methodology (SRM) structural health monitoring (SHM) state representation function (SRF) SRM Tool Kernel function.
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