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Discrete wavelet structure and discrete energy of classical plane light waves
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作者 Xing-Chu Zhang Wei-Long She 《Chinese Physics B》 SCIE EI CAS CSCD 2021年第4期139-143,共5页
We find by the wavelet transform that the classical plane light wave of linear polarization can be decomposed into a series of discrete Morlet wavelets.In the theoretical frame,the energy of the classical light wave b... We find by the wavelet transform that the classical plane light wave of linear polarization can be decomposed into a series of discrete Morlet wavelets.In the theoretical frame,the energy of the classical light wave becomes discrete;interestingly,the discretization is consistent with the energy division of P portions in Planck radiation theory,where P is an integer.It is shown that the changeable energy of a basic plane light wave packet or wave train is H_(0k)=nP0 kω(n=1,2,3,...;k=|k|),with discrete wavelet structure parameter n,wave vector k and idler frequency ω,and a constant p0 k.The wave-particle duality from the Mach-Zehnder interference of single photons is simulated by using random basic plane light wave packets. 展开更多
关键词 classic plane light wave discrete wavelet structure discrete energy
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Three New Hydrogenosuccinate and Succinate Adducts Complexes:Synthesis and Spectroscopic Study
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作者 Boucar Diouf Waly Diallo +3 位作者 Bocar Traoré Daouda Ndoye Cheikh Abdoul Khadir Diop Mamadou Sidibé 《Journal of Environmental Science and Engineering(A)》 CAS 2024年第6期207-210,共4页
One new hydrogenosuccinate and two succinate adduct and complex have been synthesized and studied by infrared,UV-Visible and NMR(Nuclear Magnetic Resonance Spectroscopy)^(119)Sn spectroscopies.The suggested structure ... One new hydrogenosuccinate and two succinate adduct and complex have been synthesized and studied by infrared,UV-Visible and NMR(Nuclear Magnetic Resonance Spectroscopy)^(119)Sn spectroscopies.The suggested structure is discrete,the hydrogenosuccinate behaving as a monodentate ligand or only involved in hydrogen bonding,the environment around the magnesium centre being triangular(compound 3).The succiate anion is a monochelating ligand(compound 1 and 2).In all the suggested structures,when extra hydrogen bonds are considered,supramolecular architectures are obtained(compound 2 and 3). 展开更多
关键词 Discrete structures hydrogen bonds monochelating MONODENTATE triangular or trigonal bipyramidal or tetrahedral environments
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Some Salicylato New Organotin (IV) and Copper Chloride Adducts and Derivative: Synthesis and Spectroscopic Study
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作者 Boucar Diouf Waly Diallo +1 位作者 Bocar Traoré Mamadou Sidibé 《Journal of Materials Science and Chemical Engineering》 2024年第10期13-17,共5页
Three new salicylate complexes and derivatives have been synthesized and studied by infrared, 119Sn NMR and UV-visible spectroscopies. The suggested structures for the two compounds are discrete with NH-O and NH-Cl hy... Three new salicylate complexes and derivatives have been synthesized and studied by infrared, 119Sn NMR and UV-visible spectroscopies. The suggested structures for the two compounds are discrete with NH-O and NH-Cl hydrogen bonds. The salicylate oxyanion is monochelating for the first salicylate compound with an octahedral tin (IV) centre and monodentate for the second salicylate compound, the environments around the tin centre being tetrahedral. For the cooper complex, the salicylate ligand is monochelating and the environments around the copper atom centre are tetrahedral. 展开更多
关键词 Discrete structures Hydrogen Bonds Monochelating Monodentate Octahedral or Tetrahedral Environments
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A Hierarchy of Integrable Lattice Soliton Equations and New Integrable Symplectic Map 被引量:1
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作者 SUN Ye-Peng CHEN Deng-Yuan XU Xi-Xiang 《Communications in Theoretical Physics》 SCIE CAS CSCD 2006年第3期405-410,共6页
Starting from a discrete spectral problem, a hierarchy of integrable lattice soliton equations is derived. It is shown that the hierarchy is completely integrable in the Liouville sense and possesses discrete bi-Hamil... Starting from a discrete spectral problem, a hierarchy of integrable lattice soliton equations is derived. It is shown that the hierarchy is completely integrable in the Liouville sense and possesses discrete bi-Hamiltonian structure. A new integrable symplectic map and finite-dimensional integrable systems are given by nonlinearization method. The binary Bargmann constraint gives rise to a Biicklund transformation for the resulting integrable lattice equations. At last, conservation laws of the hierarchy are presented. 展开更多
关键词 lattice soliton equation discrete Hamiltonian structure integrable symplectic map
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A Hierarchy of Nonlinear Lattice Soliton Equations and Its Darboux Transformation
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作者 丁海勇 孙业朋 薛丰昌 《Communications in Theoretical Physics》 SCIE CAS CSCD 2010年第1期13-16,共4页
A hierarchy of nonlinear lattice soliton equations is derived from a new discrete spectral problem. The Hamiltonian structure of the resulting hierarchy is constructed by using a trace identity formula. Moreover, a Da... A hierarchy of nonlinear lattice soliton equations is derived from a new discrete spectral problem. The Hamiltonian structure of the resulting hierarchy is constructed by using a trace identity formula. Moreover, a Darboux transformation is established with the help of gauge transformations of Lax pairs for the typical lattice soliton equations. The exact solutions are given by applying the Darboux transformation. 展开更多
关键词 lattice soliton equation discrete Hamiltonian structure Darboux transformation exact solution
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New Positive and Negative Hierarchies of Integrable Differential-Difference Equations and Conservation Laws
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作者 LI Xin-Yue ZHAO Qiu-Lan 《Communications in Theoretical Physics》 SCIE CAS CSCD 2009年第1期17-22,共6页
Two hierarchies of nonlinear integrable positive and negative lattice equations are derived from a discrete spectrak problem. The two lattice hierarchies are proved to have discrete zero curvature representations asso... Two hierarchies of nonlinear integrable positive and negative lattice equations are derived from a discrete spectrak problem. The two lattice hierarchies are proved to have discrete zero curvature representations associated with a discrete spectral problem, which also shows that the positive and negative hierarchies correspond to positive and negative power expansions of Lax operators with respect to the spectral parameter, respectively. Moreover, the integrable lattice models in the positive hierarchy are of polynomial type, and the integrable lattice models in the negative hierarchy are of rational type. Further, we construct infinite conservation laws about the positive hierarchy. 展开更多
关键词 discrete zero curvature equations Liouville integrability discrete Hamiltonian structure conservation laws
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Integrable Properties Associated with a Discrete Three-by-Three Matrix Spectral Problem
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作者 LI Xin-Yue WANG Xin-Zeng 《Communications in Theoretical Physics》 SCIE CAS CSCD 2009年第12期981-986,共6页
Based on a new discrete three-by-three matrix spectral problem, a hierarchy of integrable lattice equations with three potentials is proposed through discrete zero-curvature representation, and the resulting integrabl... Based on a new discrete three-by-three matrix spectral problem, a hierarchy of integrable lattice equations with three potentials is proposed through discrete zero-curvature representation, and the resulting integrable lattice equation reduces to the classical Toda lattice equation. It is shown that the hierarchy possesses a HamiItonian structure and a hereditary recursion operator. Finally, infinitely many conservation laws of corresponding lattice systems are obtained by a direct way. 展开更多
关键词 discrete Hamiltonian structure discrete zero-curvature representation conservation laws
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Hamiltonian System of New Nonlinear Lattice Equations
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作者 赵秋兰 于阳 李雪花 《Communications in Theoretical Physics》 SCIE CAS CSCD 2010年第4期624-630,共7页
A 3-dimensional Lie algebra sμ(3) is obtained with the help of the known Lie algebra. Based on the sμ(3), a new discrete 3 × 3 matrix spectral problem with three potentials is constructed. In virtue of disc... A 3-dimensional Lie algebra sμ(3) is obtained with the help of the known Lie algebra. Based on the sμ(3), a new discrete 3 × 3 matrix spectral problem with three potentials is constructed. In virtue of discrete zero curvature equations, a new matrix Lax representation for the hierarchy of the discrete lattice soliton equations is acquired. It is shown that the hierarchy possesses a Hamiltonian operator and a hereditary recursion operator, which implies that there exist infinitely many common commuting symmetries and infinitely many common commuting conserved functionals. 展开更多
关键词 discrete matrix spectral problem discrete zero-curvature representation discrete Hamiltonian structure
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Algebraic Structure of Discrete Zero Curvature Equations and Master Symmetries of Discrete Evolution Equations
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作者 Lin Luo 《Communications in Theoretical Physics》 SCIE CAS CSCD 2017年第2期127-130,共4页
In this paper, based on a discrete spectral problem and the corresponding zero curvature representation,the isospectral and nonisospectral lattice hierarchies are proposed. An algebraic structure of discrete zero curv... In this paper, based on a discrete spectral problem and the corresponding zero curvature representation,the isospectral and nonisospectral lattice hierarchies are proposed. An algebraic structure of discrete zero curvature equations is then established for such integrable systems. the commutation relations of Lax operators corresponding to the isospectral and non-isospectral lattice flows are worked out, the master symmetries of each lattice equation in the isospectral hierarchyand are generated, thus a τ-symmetry algebra for the lattice integrable systems is engendered from this theory. 展开更多
关键词 discrete spectral problem lattice hierarchy algebraic structure master symmetry
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A ubiquitous knowledgeable data representation model(UKRM) for three-dimensional geographic information systems(3D GIS) 被引量:3
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作者 ZHANG ShuQing ZHOU ChengHu +1 位作者 ZHANG JunYan CHEN XiangCong 《Science China Earth Sciences》 SCIE EI CAS CSCD 2016年第4期780-794,共15页
In the face of complicated, diversified three-dimensional world, the existing 3D GIS data models suffer from certain issues such as data incompatibility, insufficiency in data representation and representation types, ... In the face of complicated, diversified three-dimensional world, the existing 3D GIS data models suffer from certain issues such as data incompatibility, insufficiency in data representation and representation types, among others. It is often hard to meet the requirements of multiple application purposes(users) related to GIS spatial data management and data query and analysis, especially in the case of massive spatial objects. In this study, according to the habits of human thinking and recognition, discrete expressions(such as discrete curved surface(DCS), and discrete body(DB)) were integrated and two novel representation types(including function structure and mapping structure) were put forward. A flexible and extensible ubiquitous knowledgeable data representation model(UKRM) was then constructed, in which structurally heterogeneous multiple expressions(including boundary representation(B-rep), constructive solid geometry(CSG), functional/parameter representation, etc.) were normalized. GIS's ability in representing the massive, complicated and diversified 3D world was thus greatly enhanced. In addition, data reuse was realized, and the bridge linking static GIS to dynamic GIS was built up. Primary experimental results illustrated that UKRM was overwhelmingly superior to the current data models(e.g. IFC, City GML) in describing both regular and irregular spatial objects. 展开更多
关键词 Discrete curved surface(DCS) Discrete body(DB) Discrete structure Function structure Mapping structure "2D/3D" integrated representation 3D GIS data model UKRM model
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DISCRETE ENERGY ANALYSIS OF THE THIRD-ORDER VARIABLE-STEP BDF TIME-STEPPING FOR DIFFUSION EQUATIONS 被引量:2
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作者 Hong-lin Liao Tao Tang Tao Zhou 《Journal of Computational Mathematics》 SCIE CSCD 2023年第2期325-344,共20页
This is one of our series works on discrete energy analysis of the variable-step BDF schemes.In this part,we present stability and convergence analysis of the third-order BDF(BDF3)schemes with variable steps for linea... This is one of our series works on discrete energy analysis of the variable-step BDF schemes.In this part,we present stability and convergence analysis of the third-order BDF(BDF3)schemes with variable steps for linear diffusion equations,see,e.g.,[SIAM J.Numer.Anal.,58:2294-2314]and[Math.Comp.,90:1207-1226]for our previous works on the BDF2 scheme.To this aim,we first build up a discrete gradient structure of the variable-step BDF3 formula under the condition that the adjacent step ratios are less than 1.4877,by which we can establish a discrete energy dissipation law.Mesh-robust stability and convergence analysis in the L^(2) norm are then obtained.Here the mesh robustness means that the solution errors are well controlled by the maximum time-step size but independent of the adjacent time-step ratios.We also present numerical tests to support our theoretical results. 展开更多
关键词 Diffusion equations Variable-step third-order BDF scheme Discrete gradient structure Discrete orthogonal convolution kernels Stability and convergence
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Photo Switchable Two-step Photochromism in a Series of Ln-Phosphonate(Ln=Dy,Gd,Tb,Y)Dinuclear Complexes
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作者 HU Ji-Xiang ZHANG Qian +3 位作者 XIA Bin LIU Tao PANG Jiandong BU Xian-He 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2022年第1期58-66,共9页
Exploring the discrete complexes with multi-step coloration is still a challenge in the field of electron transfer photochromic materials. Herein, we synthesized a series of dinuclear Ln-diphosphonate compounds[Ln=Dy(... Exploring the discrete complexes with multi-step coloration is still a challenge in the field of electron transfer photochromic materials. Herein, we synthesized a series of dinuclear Ln-diphosphonate compounds[Ln=Dy(1);Gd(2);Tb(3);Y(4)] with a remarkably and reversibly photoactive coloration phenomenon. These compounds showed two-step coloration behavior, which were the first discrete architectures in the reported electron transfer photochromic complexes. This two-step coloration phenomenon was originated from the large distortion of H3-TPT acceptors, which in turn reduced the π-conjugation of electron acceptors and slowed the decay process of electron transfer. The photogenerated stable doublet radicals originated from electron transfer from diphosphonate donor to polypyridine acceptor in these complexes were detected by UV-Vis and electron spin resonance(ESR) spectra. Furthermore, the photogenerated radicals were estimated by direct current magnetic susceptibilities and variable temperature ESR spectra, suggesting the doublet radicals in the dinuclear structure for all the compounds. This work revealed a series of discrete phosphonate-based systems with a multi-step coloration process, providing a new pathway for designing multicolor photochromic materials with potential photoswitching or other applications. 展开更多
关键词 Discrete structure Donor-acceptor system Doublet radical PHOTOMAGNETISM Two-step photochromism
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Adaptive Stabilization of Neural Control for Robot Trajectory Tracking
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作者 孙富春 陆文娟 戴民 《Tsinghua Science and Technology》 SCIE EI CAS 1998年第3期99-104,共6页
A neural network (NN) based adaptive control law is proposed for the tracking control of an n link robot manipulator with unknown dynamic nonlinearities. Basis function like nets are employed to approximate the plant ... A neural network (NN) based adaptive control law is proposed for the tracking control of an n link robot manipulator with unknown dynamic nonlinearities. Basis function like nets are employed to approximate the plant nonlinearities, and the bound on the NN reconstruction error is assumed to be unknown. The proposed NN based adaptive control approach integrates an NN approach with an adaptive implementation of discrete variable structure control with a simple estimation law to estimate the upper bound on the NN reconstruction error and an additional control input to be updated as a function of the estimate. Lyapunov stability theory is used to prove the uniform ultimate boundedness of the tracking error. 展开更多
关键词 robot adaptive control basis function like nets stability discrete time variable structure
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