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MEAN APPROXIMATION BY DILATATIONS IN BERGMAN SPACES ON THE UPPER HALF-PLANE
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作者 Ali ABKAR 《Acta Mathematica Scientia》 SCIE CSCD 2023年第5期2204-2214,共11页
We study sufficient conditions on radial and non-radial weight functions on the upper half-plane that guarantee norm approximation of functions in weighted Bergman,weighted Dirichlet,and weighted Besov spaces on the u... We study sufficient conditions on radial and non-radial weight functions on the upper half-plane that guarantee norm approximation of functions in weighted Bergman,weighted Dirichlet,and weighted Besov spaces on the upper half-plane by dilatations and eventually by analytic polynomials. 展开更多
关键词 mean approximation DILATATION non-radial weight angular weight weighted Bergman space weighted Besov space
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ORDER OF MEAN APPROXIMATION BY MIXED QUASI HERMITE-FEJER INTERPOLATION
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作者 Shen Xiechang Peking University,ChinaWang Ziyu Henan University,China 《Analysis in Theory and Applications》 1993年第3期29-36,共8页
In this paper we introduce a new kind of the mixed Hermite--Fejér interpolation with boundary condi- tions and obtain the mean approximation order.Our results include a new theorem of Varma and Prasad.Be- sides,w... In this paper we introduce a new kind of the mixed Hermite--Fejér interpolation with boundary condi- tions and obtain the mean approximation order.Our results include a new theorem of Varma and Prasad.Be- sides,we also get some other results about the mean approximation. 展开更多
关键词 ORDER OF mean approximation BY MIXED QUASI HERMITE-FEJER INTERPOLATION
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BEST APPROXIMATION FOR WEIERSTRASS TRANSFORM CONNECTED WITH SPHERICAL MEAN OPERATOR 被引量:1
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作者 L.T.Rachdi N.Msehli 《Acta Mathematica Scientia》 SCIE CSCD 2012年第2期455-470,共16页
Using reproducing kernels for Hilbert spaces, we give best approximation for Weierstrass transform associated with spherical mean operator. Also, estimates of extremal functions are checked.
关键词 Weierstrass transform spherical mean operator best approximation repro-ducing kernel extremal function
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Comparison of Perturbation Theory and Mean Spherical Approximation Based on Molecular Simulation Data
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作者 刘文彬 李以圭 陆九芳 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 1999年第1期10-19,共10页
A comprehensive study on various internal energies for the dipolar hard sphere fluids, including Stockmayer fluids, the mixtures of Lennard-Jones and Stockmayer and Stockmayer fluids and the electrolyte solutions is r... A comprehensive study on various internal energies for the dipolar hard sphere fluids, including Stockmayer fluids, the mixtures of Lennard-Jones and Stockmayer and Stockmayer fluids and the electrolyte solutions is reported based on the perturbation theory and mean spherical approximation. Compared with the results of molecular simulations, it is shown that the perturbation theory is better than the mean spherical approximation. 展开更多
关键词 perturbation theory mean spherical approximation molecular simulation internal energies
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APPROXIMATION OF SPHERICAL MEANS OF MULTIPLE FOURIER INTEGRALS AND FOURIER SERIES ON SET OF FULL MEASURE
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作者 Wang Shiming Zhejiang Institute of Technology, China Math. Section Dept. of Basic Courses Zhejiang Institute of Technology, Hangzhou, 310014, China 《Analysis in Theory and Applications》 1994年第2期17-23,共7页
In this paper we consider the approximation for functions in some subspaces of L^2 by spherical means of their Fourier integrals and Fourier series on set of full measure. Two main theorems are obtained.
关键词 SET Th Pro approximation OF SPHERICAL meanS OF MULTIPLE FOURIER INTEGRALS AND FOURIER SERIES ON SET OF FULL MEASURE WANG
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APPROXIMATION OF CONTINUOUS FUNCTIONS BY GENERALIZED KARAMATA MEANS
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作者 S.A.SETTU 《Analysis in Theory and Applications》 1994年第1期88-98,共11页
A sufficient condition for the order of approximation of a continuous 2π periodic function with a given majorant for the modulus of continuity by the [F, d_n] means of its Fourier serier to be of Jackson order is obt... A sufficient condition for the order of approximation of a continuous 2π periodic function with a given majorant for the modulus of continuity by the [F, d_n] means of its Fourier serier to be of Jackson order is obtained. This sufficient condition is shown to be not enough for the order of approximation by partial sums of their Fourier series to be of Jackson order. The error estimate is shown to be the best possible. 展开更多
关键词 exp approximation OF CONTINUOUS FUNCTIONS BY GENERALIZED KARAMATA meanS
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APPROXIMATION BY FABER-LAURENT RATIONAL FUNCTIONS IN THE MEAN OF FUNCTIONS OF CLASS LP(T) WITH 1
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作者 A. Cavus D. M. Israfilov 《Analysis in Theory and Applications》 1995年第1期105-118,共14页
Let Γ be a regular curve and Lp (Γ), 1<p<+∞. be the class of all complex - valued functions f de-fined on Γ which are such that |f|p is mtegrabie in sense of Lebesgue. In this work, we define the k th p-Fabc... Let Γ be a regular curve and Lp (Γ), 1<p<+∞. be the class of all complex - valued functions f de-fined on Γ which are such that |f|p is mtegrabie in sense of Lebesgue. In this work, we define the k th p-Fabcrpolynomial F k,p (z),the kth p-Faber principle part F k.p (1/z) for Γ , and defined the nth p-Fcber- Laurent rational function Rn.p (f, z) and p- generalized modulus of continuity Ωp(f, t) of a function f of Lp(Γ) We inves-tigate some properties of Fk,p (z) and Fk.p (1/z). And then we prove a direct theorem characterizing the degree of approximation with respect to Ω (. , t) in the mean of functions of Lp(Γ) by the rational junctions Rn.p (. . z). 展开更多
关键词 approximation BY FABER-LAURENT RATIONAL FUNCTIONS IN THE mean OF FUNCTIONS OF CLASS LP WITH 1 Rational
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Sub-Differential Characterizations of Non-Smooth Lower Semi-Continuous Pseudo-Convex Functions on Real Banach Spaces
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作者 Akachukwu Offia Ugochukwu Osisiogu +4 位作者 Theresa Efor Friday Oyakhire Monday Ekhator Friday Nkume Sunday Aloke 《Open Journal of Optimization》 2023年第3期99-108,共10页
In this paper, we characterize lower semi-continuous pseudo-convex functions f : X → R ∪ {+ ∞} on convex subset of real Banach spaces K  ⊂ X with respect to the pseudo-monotonicity of its Clarke-Rockafellar Su... In this paper, we characterize lower semi-continuous pseudo-convex functions f : X → R ∪ {+ ∞} on convex subset of real Banach spaces K  ⊂ X with respect to the pseudo-monotonicity of its Clarke-Rockafellar Sub-differential. We extend the results on the characterizations of non-smooth convex functions f : X → R ∪ {+ ∞} on convex subset of real Banach spaces K  ⊂ X with respect to the monotonicity of its sub-differentials to the lower semi-continuous pseudo-convex functions on real Banach spaces. 展开更多
关键词 Real Banach Spaces Pseudo-Convex Functions Pseudo-Monotone Maps Sub-Differentials Lower Semi-Continuous Functions and Approximate mean Value Inequality
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Self-consistent mean field approximation and application in three-flavor NJL model 被引量:1
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作者 Zi-Xiong Yu Tong Zhao Hong-Shi Zong 《Chinese Physics C》 SCIE CAS CSCD 2020年第7期111-117,共7页
In this study,we apply a self-consistent mean field approximation of the three-flavor Nambu–Jona-Lasinio(NJL)model and compare it with the two-flavor NJL model.The self-consistent mean field approximation introduces ... In this study,we apply a self-consistent mean field approximation of the three-flavor Nambu–Jona-Lasinio(NJL)model and compare it with the two-flavor NJL model.The self-consistent mean field approximation introduces a new parameter,α,that cannot be fixed in advance by the mean field approach itself.Due to the lack of experimental data,the parameter,α,is undetermined.Hence,it is regarded as a free parameter and its influence on the chiral phase transition of strong interaction matter is studied based on this self-consistent mean field approximation.αaffects numerous properties of the chiral phase transitions,such as the position of the phase transition point and the order of phase transition.Additionally,increasingαwill decrease the number densities of different quarks and increase the chemical potential at which the number density of the strange quark is non-zero.Finally,we observed thatαaffects the equation of state(EOS)of the quark matter,and the sound velocity can be calculated to determine the stiffness of the EOS,which provides a good basis for studying the neutron star mass-radius relationship. 展开更多
关键词 chiral phase transition finite density NJL model self-consistent mean field approximation
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Magnetocaloric effect in ErCo2 compound
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作者 邹君鼎 沈保根 孙继荣 《Chinese Physics B》 SCIE EI CAS CSCD 2007年第7期1817-1821,共5页
The ErCo2 compound is prepared by arc-melting and its entropy changes are calculated using Maxwell relation. Its entropy change reaches 38 J/(kg·K) and its refrigerant capacity achieves 291 J/kg at 0-5 T. The m... The ErCo2 compound is prepared by arc-melting and its entropy changes are calculated using Maxwell relation. Its entropy change reaches 38 J/(kg·K) and its refrigerant capacity achieves 291 J/kg at 0-5 T. The mean field approximation is used to calculate the magnetic entropy of ErCo2 compound. Results estimated by using the Maxwell relation deviate from mean field approximation calculations in ferrimagnetic state; however, the data obtained by the two ways are consistent in the vicinity of phase transition or at higher temperatures. This indicates that entropy changes are mainly derived from magnetic degree of freedom, and the lattice has almost no contribution to the entropy change in the vicinity of phase transition but its influence is obvious in the ferrimagnetic state below TC. 展开更多
关键词 magnetocaloric effect mean field approximation metamagnetic transition
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Magnetic properties and magnetocaloric effect in TbCo2-xFex compounds
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作者 邹君鼎 沈保根 孙继荣 《Chinese Physics B》 SCIE EI CAS CSCD 2007年第12期3843-3847,共5页
Magnetic properties and magnetocaloric effect in TbCo2-xFex compounds are studied by DC magnetic measurement. With increasing content of Fe, the entropy changes decrease slightly, though the Curie temperature is tuned... Magnetic properties and magnetocaloric effect in TbCo2-xFex compounds are studied by DC magnetic measurement. With increasing content of Fe, the entropy changes decrease slightly, though the Curie temperature is tuned from 231 K (x = 0) to 303 K (x = 0.1). Magnetic entropies of TbCo2 compound are calculated by using mean field approximation (MFA). Results estimated by using Maxwell relation are consistent with that of MFA calculation. It is shown that the entropy changes are mainly derived from the magnetic entropy changes. The lattice has almost no contribution to the entropy change in the vicinity of phase transition. 展开更多
关键词 magnetocaloric effect mean field approximation metamagnetic transition
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Mean field study of a propagation-turnover lattice model for the dynamics of histone marking
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作者 Fan Yao FangTing Li TieJun Li 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS CSCD 2017年第2期49-63,共15页
We present a mean field study of a propagation-tumover lattice model, which was proposed by Hodges and Crabtree [Proc. Nat. Acad. Sci. 109, 13296 (2012)] for understanding how posttranslational histone marks modulat... We present a mean field study of a propagation-tumover lattice model, which was proposed by Hodges and Crabtree [Proc. Nat. Acad. Sci. 109, 13296 (2012)] for understanding how posttranslational histone marks modulate gene expression in mammalian ceils. The kinetics of the lattice model consists of nucleation, propagation and turnover mechanisms, and exhibits second-order phase transition for the histone marking domain. We showed rigorously that the dynamics essentially depends on a non-dimensional parameter k = k+/k-, the ratio between the propagation and turnover rates, which has been observed in the simulations. We then studied the lowest order mean field approximation, and observed the phase transition with an analytically obtained critical parameter. The boundary layer analysis was utilized to investigate the structure of the decay profile of the mark density. We also studied the higher order mean field approximation to achieve sharper estimate of the critical transition parameter and more detailed features. The comparison between the simulation and theoretical results shows the validity of our theory. 展开更多
关键词 histone marking contact process mean field approximation boundary layer analysis
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Quasielastic electron scattering in a derivative coupling model with relativistic random phase approximation
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作者 陈晏军 《Chinese Physics C》 SCIE CAS CSCD 2013年第7期33-38,共6页
We apply the derivative coupling model with ZM and ZM3 parameters to investigate the longitudinal response function in quasielastic electron scattering in the relativistic random phase approximation. The non-spectral ... We apply the derivative coupling model with ZM and ZM3 parameters to investigate the longitudinal response function in quasielastic electron scattering in the relativistic random phase approximation. The non-spectral method is chosen to describe the nucleon Green's function in a finite nucleus. Some remarks have been made in conclusion. 展开更多
关键词 quasielasic electron scattering derivative coupling model relativistic random phase approximation relativistic mean field theory
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Recent Advances in Study on Thermodynamic Models for Real Systems Including Electrolytes 被引量:2
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作者 李以圭 《Tsinghua Science and Technology》 SCIE EI CAS 2006年第2期181-187,共7页
A comprehensive review of recent advances in study on thermodynamic models for real electrolyte solutions is presented. The differences between primitive and non-primitive electrolyte models are demonstrated. Some new... A comprehensive review of recent advances in study on thermodynamic models for real electrolyte solutions is presented. The differences between primitive and non-primitive electrolyte models are demonstrated. Some new thermodynamic models for electrolyte solutions based on the mean spherical approximation and perturbation theory are introduced. An extended scaled-particle theory and modified CleggPitzer equation are presented for physical and chemical absorption processes with mixed solvents, respectively. A pseudo one-component two-Yukawa equation of state is used for the aqueous two-phase extraction process in charged colloidal systems. 展开更多
关键词 primitive and non-primitive electrolyte models mean spherical approximation scaled-particletheory Clegg-Pitzer equation physical absorption chemical absorption aqueous two-phaseextraction two-Yukawa potential
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Influence of coupling constants on nuclear symmetry energy
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作者 刘贝贝 欧阳飞 陈伟 《Chinese Physics C》 SCIE CAS CSCD 2013年第4期57-60,共4页
By studying the energy of neutron star matter, we discuss the nuclear symmetry energy at different baryon densities and different coupling constants in the relativistic mean field approximation. The results show that ... By studying the energy of neutron star matter, we discuss the nuclear symmetry energy at different baryon densities and different coupling constants in the relativistic mean field approximation. The results show that the symmetry energy increases with baryon density at various coupling constants and incompressibilities. Further-more, the symmetry energy at saturation density increases with increasing incompressibility at fixed d, and decreases at fixed c. Specifically, when coupling constants gv and gs are fixed, respectively, the symmetry energy has a little change with increasing incompressibility. It is demonstrated that the NN coupling constants have greater influences on the symmetry energy than the self-coupling constants. 展开更多
关键词 symmetry energy relativistic mean field approximation coupling constant INCOMPRESSIBILITY
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Effects of the density dependence of the symmetry energy on neutron stars
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作者 刘晓进 吴琛 任中洲 《Chinese Physics C》 SCIE CAS CSCD 2010年第11期1709-1713,共5页
In this paper,we include the density dependence behavior of the symmetry energy in the improved quark mass density dependent (IQMDD) model.Under the mean field approximation,this model is applied to investigate neut... In this paper,we include the density dependence behavior of the symmetry energy in the improved quark mass density dependent (IQMDD) model.Under the mean field approximation,this model is applied to investigate neutron star matter and neutron stars successfully.Effects of the density dependence of the symmetry energy on neutron stars are described. 展开更多
关键词 symmetry energy neutron stars relativistic mean field approximation quark-meson coupling
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Recent Advances in the Use of Statistical Mechanics to Establish Molecular Thermodynamic Models for Electrolyte Solutions
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作者 李以圭 《Tsinghua Science and Technology》 SCIE EI CAS 2004年第4期444-454,共11页
Based on statistical mechanics, a review of recent theoretical studies of real electrolyte solutions is presented from three aspects, namely, molecular simulation, mean spherical approximation (MSA), and perturbation ... Based on statistical mechanics, a review of recent theoretical studies of real electrolyte solutions is presented from three aspects, namely, molecular simulation, mean spherical approximation (MSA), and perturbation theory. Recent advances in studies of three kinds of electrostatic potentials of mean force, three kinds of internal energies (ion-ion, ion-dipole, and dipole-dipole interactions), and three kinds of electro-lyte models (primitive, non-primitive, and solvent primitive models) are introduced. The advantages and dis-advantages between primitive and non-primitive models, and between MSA and perturbation theory are dis-cussed. Some new equations of state (EOSs) based on MSA and perturbation theory for real electrolyte so-lutions are introduced. The one-Yukawa EOS and the two-Yukawa EOS for charged colloid systems are presented. 展开更多
关键词 statistical mechanics electrolyte solutions molecular simulation perturbation theory mean spherical approximation primitive and non-primitive models equation of state
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