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Surplus Space Method: A New Numerical Model for Prediction of Shallow-seated Magmatic Bodies 被引量:8
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作者 DENGJun HUANGDinghua +4 位作者 WANGQingfeit WANLi YAOLingqing GAOBangfei LiuYan 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2004年第6期1245-1249,共5页
Based on the data of field measurement and drilling in the Tongling area, a series of numerical simulations are carried out by using the 'Surplus Space Method' (SSM), which is first put forward in this paper a... Based on the data of field measurement and drilling in the Tongling area, a series of numerical simulations are carried out by using the 'Surplus Space Method' (SSM), which is first put forward in this paper and applied to predict the shallow-seated magmatic bodies. The results of the numerical simulations show the existence and the 3-D shape of a conical magmatic structure at a depth of-1000 m beneath the center of the area: its top offsets southwards and bifurcates to several branches, while its lower part stretches northeastwards and contracts rapidly to a point at about -1000 m depth. This point is reckoned to be a 'sink' of magma system, transferring ore materials and heat energy from the deep magma chamber to the sub-surface apophyses. The preliminary application of the SSM proves that it may be developed as a new detection means for determining the existence of shallow-seated magmatic bodies and analyzing their three-dimensional features. 展开更多
关键词 Tongling area shallow-seated magmatic bodies surplus space method numerical simulation
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A Fast Algorithm for Phase Grating Preparation by Real Space Method
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作者 Qiuxiang LIU and Yuanming WANG Laboratory of Atomic Imaging of Solids, Institute of Metal Research, Chinese Academy of Sciences, Shengyang 110015, China Qibin YANG and Xiaohong YAN Institute of Modern Physics, Xiangtan University, Xiangtan 411105, China 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2001年第2期240-242,共3页
Making use of this expression to calculate the phase grating in high resolution image simulation can greatly reduce the calculating time. In this paper, the derivation of the expression is introduced, and then the com... Making use of this expression to calculate the phase grating in high resolution image simulation can greatly reduce the calculating time. In this paper, the derivation of the expression is introduced, and then the computer routine is explained in details. Finally the potential projection map of Mg44Rh7 along [001] direction is shown as an illustration. All operations are carried out in real space, so we call the calculation method as the real space method. 展开更多
关键词 A Fast Algorithm for Phase Grating Preparation by Real space method
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STATE SPACE METHODS FOR DECENTRALIZED H_∞ CONTROL
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作者 Wu Min Gut Weihua Chen Ning(Department of Automatic Control Engineering, Central South University of Technology, Changsha, 410083, China) 《Journal of Central South University》 SCIE EI CAS 1994年第1期91-96,共6页
This paper presents state space methods for decentralized Hoe control, which contain two respects: a parametrization approach and an iterative algorithm. For large scale systems with N subsystems, decentralized Hoe c... This paper presents state space methods for decentralized Hoe control, which contain two respects: a parametrization approach and an iterative algorithm. For large scale systems with N subsystems, decentralized Hoe con trollers can be derived by a parametrization result for centralized Her: controllers and designed by an iterative algorithm with structured constraint to the controllers. 展开更多
关键词 DECENTRALIZED CONTROL STATE space method H_∞ CONTROL
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Solution of Klein-Gordon Equation by a Method of Lines Using Reproducing Kernel Hilbert Space Method
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作者 PATEL Kaushal PATEL Gautam 《Journal of Partial Differential Equations》 CSCD 2024年第3期251-262,共12页
This paper presents a method of lines solution based on the reproducing kernel Hilbert space method to the nonlinear one-dimensional Klein-Gordon equation that arises in many scientific fields areas.Our method uses di... This paper presents a method of lines solution based on the reproducing kernel Hilbert space method to the nonlinear one-dimensional Klein-Gordon equation that arises in many scientific fields areas.Our method uses discretization of the partial derivatives of the space variable to get a system of ODEs in the time variable and then solve the system of ODEs using reproducing kernel Hilbert space method.Consider two examples to validate the proposed method.Compare the results with the exact solution by calculating the error norms L_(2) and L_(∞) at various time levels.The results show that the presented scheme is a systematic,effective and powerful technique for the solution of Klein-Gordon equation. 展开更多
关键词 method of Lines reproducing kernel Hilbert space method Klein-Gordon equation
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AN ELEMENTARY ANALYSIS OF PROBLEMS IN APPLICATION OF SPACE METHOD IN STRATEGIC MANAGEMENT OF ENTERPRISES
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作者 曹琨生 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 1998年第2期103-107,共5页
Although it is still a new and developing subject, strategic management of enterprises, the importance of which will be understood by more and more enterprises as the reform and development is deepened, will surely be... Although it is still a new and developing subject, strategic management of enterprises, the importance of which will be understood by more and more enterprises as the reform and development is deepened, will surely be applied finally. This paper expounds how to apply the Delphi method to determine the essential elements in management and to evaluate enterprises in strategic position and action evaluation (SPACE) method of strategic management of enterprises. Meanwhile, its determination and evaluation are so realistic that they describe the strategic positions at which enterprises may be in the present competitive environment, and they establish a basis for enterprises to correctly choose their strategies of development. 展开更多
关键词 strategic management enterprise management space method Delphi method strategic position vector line
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基于CiteSpace的红色文创设计可视化分析与方法研究 被引量:1
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作者 刘洪波 卢敏学 《包装工程》 CAS 北大核心 2024年第18期330-340,共11页
目的基于CiteSpace概述国内红色文创设计的发展状况,梳理关于红色文创设计的相关方法与理论模型,探讨未来红色文创设计发展的趋势,为研究者提供相关设计思路与发展动向。方法通过对国内相关文献的研究,梳理了红色文创设计的概念与发展现... 目的基于CiteSpace概述国内红色文创设计的发展状况,梳理关于红色文创设计的相关方法与理论模型,探讨未来红色文创设计发展的趋势,为研究者提供相关设计思路与发展动向。方法通过对国内相关文献的研究,梳理了红色文创设计的概念与发展现状,归纳了当前红色文创设计中包括文化转译维度、文化层次理论、叙事性设计的三种主要方法与理论模型。结论目前红色文创设计方法较为单一,很难满足用户的不同需求,且缺乏具体针对性的完整理论体系与设计方法。在今后的红色文创设计中,可以综合运用叙事性及文化转译维度等设计理论和手段,对红色文创设计和方法加以探究和创新,打造具有中国特色的红色文创产品,使红色文化得到更好的普及和弘扬。 展开更多
关键词 CITEspace 红色文创 设计方法 可视化 发展趋势
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Poisson theory and integration method of Birkhoffian systems in the event space 被引量:6
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作者 张毅 《Chinese Physics B》 SCIE EI CAS CSCD 2010年第8期80-84,共5页
This paper focuses on studying the Poisson theory and the integration method of a Birkhoffian system in the event space. The Birkhoff's equations in the event space are given. The Poisson theory of the Birkhoffian sy... This paper focuses on studying the Poisson theory and the integration method of a Birkhoffian system in the event space. The Birkhoff's equations in the event space are given. The Poisson theory of the Birkhoffian system in the event space is established. The definition of the Jacobi last multiplier of the system is given, and the relation between the Jacobi last multiplier and the first integrals of the system is discussed. The researches show that for a Birkhoffian system in the event space, whose configuration is determined by (2n + 1) Birkhoff's variables, the solution of the system can be found by the Jacobi last multiplier if 2n first integrals are known. An example is given to illustrate the application of the results. 展开更多
关键词 Birkhoffian system event space method of integration Jacobi last multiplier
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IMPROVED GRADIENT METHOD FOR MONOTONE AND LIPSCHITZ CONTINUOUS MAPPINGS IN BANACH SPACES 被引量:1
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作者 Kazuhide NAKAJO 《Acta Mathematica Scientia》 SCIE CSCD 2017年第2期342-354,共13页
Let C be a nonempty closed convex subset of a 2-uniformly convex and uniformly smooth Banach space E and {An}n∈N be a family of monotone and Lipschitz continuos mappings of C into E*. In this article, we consider th... Let C be a nonempty closed convex subset of a 2-uniformly convex and uniformly smooth Banach space E and {An}n∈N be a family of monotone and Lipschitz continuos mappings of C into E*. In this article, we consider the improved gradient method by the hybrid method in mathematical programming [i0] for solving the variational inequality problem for {AN} and prove strong convergence theorems. And we get several results which improve the well-known results in a real 2-uniformly convex and uniformly smooth Banach space and a real Hilbert space. 展开更多
关键词 Variational inequality problem gradient method monotone operators 2-uniformly convex Banach space hybrid method
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A method for calculating probability of collision between space objects 被引量:2
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作者 Xiao-Li Xu Yong-Qing Xiong 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2014年第5期601-609,共9页
A method is developed to calculate probability of collision. Based on geometric features of space objects during the encounter, it is reasonable to separate the radial orbital motions from those in the cross section f... A method is developed to calculate probability of collision. Based on geometric features of space objects during the encounter, it is reasonable to separate the radial orbital motions from those in the cross section for most encounter events that occur in a near-circular orbit. Therefore, the probability of collision caused by differences in both altitude of the orbit in the radial direction and the probability of collision caused by differences in arrival time in the cross section are calculated. The net probability of collision is expressed as an explicit expression by multiplying the above two components. Numerical cases are applied to test this method by comparing the results with the general method. The results indicate that this method is valid for most encounter events that occur in near-circular orbits. 展开更多
关键词 methods: analytical -- reference systems -- catalogs -- space vehicles-- celestial mechanics
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Forecasting available parking space with largest Lyapunov exponents method 被引量:3
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作者 季彦婕 汤斗南 +2 位作者 郭卫红 BLYTHE T.Phil 王炜 《Journal of Central South University》 SCIE EI CAS 2014年第4期1624-1632,共9页
The techniques to forecast available parking space(APS) are indispensable components for parking guidance systems(PGS). According to the data collected in Newcastle upon Tyne, England, the changing characteristics of ... The techniques to forecast available parking space(APS) are indispensable components for parking guidance systems(PGS). According to the data collected in Newcastle upon Tyne, England, the changing characteristics of APS were studied. Thereafter, aiming to build up a multi-step APS forecasting model that provides richer information than a conventional one-step model, the largest Lyapunov exponents(largest LEs) method was introduced into PGS. By experimental tests conducted using the same dataset, its prediction performance was compared with traditional wavelet neural network(WNN) method in both one-step and multi-step processes. Based on the results, a new multi-step forecasting model called WNN-LE method was proposed, where WNN, which enjoys a more accurate performance along with a better learning ability in short-term forecasting, was applied in the early forecast steps while the Lyapunov exponent prediction method in the latter steps precisely reflect the chaotic feature in latter forecast period. The MSE of APS forecasting for one hour time period can be reduced from 83.1 to 27.1(in a parking building with 492 berths) by using largest LEs method instead of WNN and further reduced to 19.0 by conducted the new method. 展开更多
关键词 available parking space Lyapunov exponents wavelet neural network multi-step forecasting method
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Mixed time discontinuous space-time finite element method for convection diffusion equations 被引量:1
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作者 刘洋 李宏 何斯日古楞 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2008年第12期1579-1586,共8页
A mixed time discontinuous space-time finite element scheme for secondorder convection diffusion problems is constructed and analyzed. Order of the equation is lowered by the mixed finite element method. The low order... A mixed time discontinuous space-time finite element scheme for secondorder convection diffusion problems is constructed and analyzed. Order of the equation is lowered by the mixed finite element method. The low order equation is discretized with a space-time finite element method, continuous in space but discontinuous in time. Stability, existence, uniqueness and convergence of the approximate solutions are proved. Numerical results are presented to illustrate efficiency of the proposed method. 展开更多
关键词 convection diffusion equations mixed finite element method time discontinuous space-time finite element method CONVERGENCE
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Fast Measurement of Dielectric Conductivity for Space Application by Surface Potential Decay Method 被引量:1
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作者 全荣辉 周凯 +2 位作者 方美华 池卫英 张振龙 《Chinese Physics Letters》 SCIE CAS CSCD 2017年第6期104-106,共3页
Surface potential decay of polymers for electrical insulation can help to determine the dark conductivity for spacecraft charging analysis. Due to the existence of radiation-induced conductivity, it decays fast in the... Surface potential decay of polymers for electrical insulation can help to determine the dark conductivity for spacecraft charging analysis. Due to the existence of radiation-induced conductivity, it decays fast in the first few hours after irradiation and exponentially slowly for the remaining time. The measurement of dark conductivity with this method usually takes the slow part and needs a couple of days. Integrating the Fowler formula into the deep dielectric charging equations, we obtain a new expression for the fast decay part. The experimental data of different materials, dose rates and temperatures are fitted by the new expression. Both the dark conductivity and the radiation-induced conductivity are derived and compared with other methods. The result shows a good estimation of dark conductivity and radiation-induced conductivity in high-resistivity polymers, which enables a fast measurement of dielectric conductivity within about 600 rain after irradiation. 展开更多
关键词 Fast Measurement of Dielectric Conductivity for space Application by Surface Potential Decay method
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THE SPACE-TIME FINITE ELEMENT METHOD FOR PARABOLIC PROBLEMS 被引量:5
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作者 LI Hong(李宏) +1 位作者 LIU Ru-xun(刘儒勋) 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2001年第6期687-700,共14页
Adaptive space-time finite element method, continuous in space but discontinuous in time for semi-linear parabolic problems is discussed. The approach is based on a combination of finite element and finite difference ... Adaptive space-time finite element method, continuous in space but discontinuous in time for semi-linear parabolic problems is discussed. The approach is based on a combination of finite element and finite difference techniques. The existence and uniqueness of the weak solution are proved without any assumptions on choice of the spacetime meshes. Basic error estimates in L-infinity (L-2) norm, that is maximum-norm in time, L-2-norm in space are obtained. The numerical results are given in the last part and the analysis between theoretic and experimental results are obtained. 展开更多
关键词 semi-linear parabolic equations space-time finite element method existence and uniquess error estimate
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Anti-plane deformations around arbitrary-shaped canyons on a wedge-shape half-space:moment method solutions 被引量:19
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作者 Nazaret Dermendjian Vincent W.Lee 梁建文 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2003年第2期281-287,共7页
The wave propagation behavior in an elastic wedge-shaped medium with an arbitrary shaped cylindrical canyon at its vertex has been studied.Numerical computation of the wave displacement field is carried out on and nea... The wave propagation behavior in an elastic wedge-shaped medium with an arbitrary shaped cylindrical canyon at its vertex has been studied.Numerical computation of the wave displacement field is carried out on and near the canyon surfaces using weighted-residuals(moment method).The wave displacement fields are computed by the residual method for the cases of elliptic,circular,rounded-rectangular and flat-elliptic canyons,The analysis demonstrates that the resulting surface displacement depends,as in similar previous analyses,on several factors including,but not limited,to the angle of the wedge,the geometry of the vertex,the frequencies of the incident waves,the angles of incidence,and the material properties of the media.The analysis provides intriguing results that help to explain geophysical observations regarding the amplification of seismic energy as a function of site conditions. 展开更多
关键词 weighted-residual moment method wedge half-space arbitrary-shaped cicular elliptic rectangular canyons
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Multi-objective Evolutionary Algorithm Based on Target Space Partitioning Method
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作者 尚兆霞 刘弘 李焱 《Journal of Donghua University(English Edition)》 EI CAS 2011年第2期177-181,共5页
Considering the defects of conventional optimization methods, a novel optimization algorithm is introduced in this paper. Target space partitioning method is used in this algorithm to solve multi-objective optimizatio... Considering the defects of conventional optimization methods, a novel optimization algorithm is introduced in this paper. Target space partitioning method is used in this algorithm to solve multi-objective optimization problem, thus achieve the coherent solution which can meet the requirements of all target functions, and improve the population's overall evolution level. The algorithm which guarantees diversity preservation and fast convergence to the Pareto set is applied to structural optimization problems. The empirical analysis supports the algorithm and gives an example with program. 展开更多
关键词 OPTIMIZATION ALGORITHM MULTI-OBJECTIVE TARGET space partitioning method
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PARAMETRIC EQUATIONS OF NONHOLONOMIC NONCONSERVATIVE SYSTEMS IN THE EVENT SPACE AND THE METHOD OF THEIR INTEGRATION 被引量:10
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作者 Mei Fengxiang (Beijing Institute of Technology) 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 1990年第2期160-168,共9页
In this paper,the parametric equations with multipliers of nonholonomic nonconservative sys- tems in the event space are established,their properties are studied,and their explicit formulation is obtained. And then th... In this paper,the parametric equations with multipliers of nonholonomic nonconservative sys- tems in the event space are established,their properties are studied,and their explicit formulation is obtained. And then the field method for integrating these equations is given.Finally,an example illustrating the appli- cation of the integration method is given. 展开更多
关键词 event space nonholonomic nonconservative system parametric equation integration method
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H^1 space-time discontinuous finite element method for convection-diffusion equations
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作者 何斯日古楞 李宏 刘洋 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2013年第3期371-384,共14页
An H1 space-time discontinuous Galerkin (STDG) scheme for convection- diffusion equations in one spatial dimension is constructed and analyzed. This method is formulated by combining the H1 Galerkin method and the s... An H1 space-time discontinuous Galerkin (STDG) scheme for convection- diffusion equations in one spatial dimension is constructed and analyzed. This method is formulated by combining the H1 Galerkin method and the space-time discontinuous finite element method that is discontinuous in time and continuous in space. The existence and the uniqueness of the approximate solution are proved. The convergence of the scheme is analyzed by using the techniques in the finite difference and finite element methods. An optimal a-priori error estimate in the L∞ (H1) norm is derived. The numerical exper- iments are presented to verify the theoretical results. 展开更多
关键词 convection-diffusion equation H1 method space-time discontinuous finiteelement method error estimate
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INVERSE POWER METHOD AND WEIGHTED SOBOLEV SPACES
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作者 丁毅 《Acta Mathematica Scientia》 SCIE CSCD 1992年第1期7-21,共15页
1. Introduction This paper is a continuation of the paper [5]. Now we want to treat the problem
关键词 INVERSE POWER method AND WEIGHTED SOBOLEV spaceS
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Finite Element Method for a Kind of Two-Dimensional Space-Fractional Diffusion Equation with Its Implementation 被引量:1
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作者 Beiping Duan Zhoushun Zheng Wen Cao 《American Journal of Computational Mathematics》 2015年第2期135-157,共23页
In this article, we consider a two-dimensional symmetric space-fractional diffusion equation in which the space fractional derivatives are defined in Riesz potential sense. The well-posed feature is guaranteed by ener... In this article, we consider a two-dimensional symmetric space-fractional diffusion equation in which the space fractional derivatives are defined in Riesz potential sense. The well-posed feature is guaranteed by energy inequality. To solve the diffusion equation, a fully discrete form is established by employing Crank-Nicolson technique in time and Galerkin finite element method in space. The stability and convergence are proved and the stiffness matrix is given analytically. Three numerical examples are given to confirm our theoretical analysis in which we find that even with the same initial condition, the classical and fractional diffusion equations perform differently but tend to be uniform diffusion at last. 展开更多
关键词 GALERKIN Finite Element method SYMMETRIC space-Fractional Diffusion Equation Stability Convergence IMPLEMENTATION
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SPACE-TIME DISCONTINUOUS GALERKIN METHOD FOR MAXWELL EQUATIONS IN DISPERSIVE MEDIA
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作者 汪波 谢资清 张智民 《Acta Mathematica Scientia》 SCIE CSCD 2014年第5期1357-1376,共20页
In this paper, a unified model for time-dependent Maxwell equations in dispersive media is considered. The space-time DG method developed in [29] is applied to solve the un-derlying problem. Unconditional L2-stability... In this paper, a unified model for time-dependent Maxwell equations in dispersive media is considered. The space-time DG method developed in [29] is applied to solve the un-derlying problem. Unconditional L2-stability and error estimate of order O?τr+1+hk+1/2? are obtained when polynomials of degree at most r and k are used for the temporal dis-cretization and spatial discretization respectively. 2-D and 3-D numerical examples are given to validate the theoretical results. Moreover, numerical results show an ultra-convergence of order 2r+1 in temporal variable t. 展开更多
关键词 Maxwell equations dispersive media space-time DG method L2-stability L2-error estimate
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