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Investigation of the Metabolic Flux Analysis Method for Overdetermined System 被引量:1
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作者 马红武 郭晓峰 +1 位作者 赵学明 鲁晋 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2002年第2期236-239,共4页
With the xanthan synthesis in Xanthomoaas campestris as an example, two methods for metabolic flux analysis of overdetermined system, the experimental data error minimization method and the equation error minimization... With the xanthan synthesis in Xanthomoaas campestris as an example, two methods for metabolic flux analysis of overdetermined system, the experimental data error minimization method and the equation error minimization method, are compared from their mathematical basis, rationality of the results and the easiness of computation. The results show that the experimental data error minimization method is appropriate in metabolic flux analysis of overdetermined system. 展开更多
关键词 metabolic flux analysis overdetermined system Xanthomonas campestris
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Processing Human Colonic Pressure Signals by Using Overdetermined ICA
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作者 田社平 潘城 颜国正 《Journal of Measurement Science and Instrumentation》 CAS 2010年第4期401-405,共5页
Independent component analysis (ICA) is a widely used method for blind source separation (BSS). The mature ICA model has a restriction that the number of the sources must equal to that of the sensors used to colle... Independent component analysis (ICA) is a widely used method for blind source separation (BSS). The mature ICA model has a restriction that the number of the sources must equal to that of the sensors used to collect data, which is hard to meet in most practical cases. In this paper, an overdetermined ICA method is proposed and successfully used in the analysis of human colonic pressure signals. Using principal component analysis (PCA), the method estimates the number of the sources firstly and reduces the dimensions of the observed signals to the same with that of the sources; and then, Fast- ICA is used to estimate all the sources. From 26 groups of colonic pressure recordings, several colonic motor patterns are extracted, which riot only prove the effectiveness of this method, but also greatly facilitate further medical researches. 展开更多
关键词 medical signal processing overdetermined ICA PCA colonic motor pattern
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Some Steiner Symmetry Results in Overdetermined Boundary Value Problem
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作者 Zhongbo Fang Anna Wang 《Advances in Pure Mathematics》 2011年第6期340-344,共5页
In this paper, we use the moving planes method to prove that the domain Ω and the solution u are Steiner symmetric if u is a positive solution of the overdetermined boundary value problem in Ω.
关键词 STEINER SYMMETRY MOVING PLANES Method overdetermined BOUNDARY Value Problem
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A New Class of Simple,General and Efficient Finite Volume Schemes for Overdetermined Thermodynamically Compatible Hyperbolic Systems
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作者 Saray Busto Michael Dumbser 《Communications on Applied Mathematics and Computation》 EI 2024年第3期1742-1778,共37页
In this paper,a new efficient,and at the same time,very simple and general class of thermodynamically compatiblefinite volume schemes is introduced for the discretization of nonlinear,overdetermined,and thermodynamicall... In this paper,a new efficient,and at the same time,very simple and general class of thermodynamically compatiblefinite volume schemes is introduced for the discretization of nonlinear,overdetermined,and thermodynamically compatiblefirst-order hyperbolic systems.By construction,the proposed semi-discrete method satisfies an entropy inequality and is nonlinearly stable in the energy norm.A very peculiar feature of our approach is that entropy is discretized directly,while total energy conservation is achieved as a mere consequence of the thermodynamically compatible discretization.The new schemes can be applied to a very general class of nonlinear systems of hyperbolic PDEs,including both,conservative and non-conservative products,as well as potentially stiff algebraic relaxation source terms,provided that the underlying system is overdetermined and therefore satisfies an additional extra conservation law,such as the conservation of total energy density.The proposed family offinite volume schemes is based on the seminal work of Abgrall[1],where for thefirst time a completely general methodology for the design of thermodynamically compatible numerical methods for overdetermined hyperbolic PDE was presented.We apply our new approach to three particular thermodynamically compatible systems:the equations of ideal magnetohydrodynamics(MHD)with thermodynamically compatible generalized Lagrangian multiplier(GLM)divergence cleaning,the unifiedfirst-order hyperbolic model of continuum mechanics proposed by Godunov,Peshkov,and Romenski(GPR model)and thefirst-order hyperbolic model for turbulent shallow waterflows of Gavrilyuk et al.In addition to formal mathematical proofs of the properties of our newfinite volume schemes,we also present a large set of numerical results in order to show their potential,efficiency,and practical applicability. 展开更多
关键词 overdetermined thermodynamically compatible hyperbolic systems Hyperbolic and thermodynamically compatible(HTC)finite volume schemes Abgrall framework Discrete entropy inequality Nonlinear stability in the energy norm Applications to ideal magnetohydrodynamics(MHD) Godounov-Peshkov-Romenski(GPR)model of continuum mechanics Turbulent shallow water(TSW)flows
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Serrin-Type Overdetermined Problem in H^(n)
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作者 GAO Zhenghuan JIA Xiaohan YAN Jin 《Journal of Partial Differential Equations》 CSCD 2023年第1期102-118,共17页
In this paper,we prove the symmetry of the solution to overdetermined problem for the equationσ_(k)(D^(2)u-ul)=C^(k)_(n)in hyperbolic space.Our approach is based on establishing a Rellich-Pohozaev type identity and u... In this paper,we prove the symmetry of the solution to overdetermined problem for the equationσ_(k)(D^(2)u-ul)=C^(k)_(n)in hyperbolic space.Our approach is based on establishing a Rellich-Pohozaev type identity and using a P function.Our result generalizes the overdetermined problem for Hessian equation in Euclidean space. 展开更多
关键词 overdetermined problems hyperbolic space P functions Rellich-Pohozaev identity
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PSEUDO-SOLUTION ON GEODETIC OVERDETERMINED BOUNDARY VALUE PROBLEMS 被引量:1
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作者 朱灼文 于锦海 《Science China Chemistry》 SCIE EI CAS 1992年第6期697-708,共12页
A higher step of study on the GOBVPs (geodetic overdetermined boundary value problems) is reached in this paper, which covers the proposal of new concept of pseudo-solutionon the GOBVPs, its strict definition of mathe... A higher step of study on the GOBVPs (geodetic overdetermined boundary value problems) is reached in this paper, which covers the proposal of new concept of pseudo-solutionon the GOBVPs, its strict definition of mathematics and solving principle. The so-called pseudosolution is a harmonical function having the property of optimum approximating the given boundary values in the sense of a relevant norm. Analytical expressions of the pseudo-solutions of two typical OBVPs for biboundary surfaces in physical geodesy, the problems S—D and S—N, are obtained, which is elegant and concise in form and convenient for practice, by using the derived formulas of norms of fractional exponential Sobolev's spaces in the case of spherical biboundary. The pseudo-solution is composed of two parts: the major is the solution of classical Stokes' problem, playing control role in field representation; the minor is correction term, serving the function of synergist and precision of the gravity field. Besides, a general case of the GOBVP is also dealt with. 展开更多
关键词 GEODETIC overdetermined BOUNDARY VALUE problem pseudo-solution relevant properly-posed BOUNDARY VALUE problem SYNERGISTIC GRAVITY anomaly SYNERGISTIC GRAVITY field model.
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Overdetermined Systems of First Order Partial Differential Equations with Singular Solution
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作者 Izumiya Shyuichi (Department of Mathematics,Faculty of Science,Hokkaido University,Sapporo 060,Japan)Li Bing (Department of Mathematics,Changsha University of Electric Power,Changsha 410077,China) 《Acta Mathematica Sinica,English Series》 SCIE CSCD 1997年第3期327-332,共6页
We study overdetermined systems of first order partial differential equations with singular solutions.The main result gives a characterization of such systems and asserts that the singular solution is equal to the con... We study overdetermined systems of first order partial differential equations with singular solutions.The main result gives a characterization of such systems and asserts that the singular solution is equal to the contact singular set. 展开更多
关键词 Singular solutions complete integrability overdetermined systems first order PDE
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Convergent Overdetermined-RBF-MLPG for Solving Second Order Elliptic PDEs
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作者 Ahmad Shirzadi Leevan Ling 《Advances in Applied Mathematics and Mechanics》 SCIE 2013年第1期78-89,共12页
This paper deals with the solvability and the convergence of a class of unsymmetric Meshless Local Petrov-Galerkin(MLPG)method with radial basis function(RBF)kernels generated trial spaces.Local weak-form testings are... This paper deals with the solvability and the convergence of a class of unsymmetric Meshless Local Petrov-Galerkin(MLPG)method with radial basis function(RBF)kernels generated trial spaces.Local weak-form testings are done with stepfunctions.It is proved that subject to sufficiently many appropriate testings,solvability of the unsymmetric RBF-MLPG resultant systems can be guaranteed.Moreover,an error analysis shows that this numerical approximation converges at the same rate as found in RBF interpolation.Numerical results(in double precision)give good agreement with the provided theory. 展开更多
关键词 Local integral equations meshless methods radial basis functions overdetermined systems SOLVABILITY convergence
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Optimal Load Balancing Leveling Method for Multi-leg Flexible Platforms 被引量:6
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作者 GANG Xianyue CHAI Shan 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2013年第5期900-908,共9页
The working platforms supported with multiple extensible legs must be leveled before they come into operation.Although the supporting stiffness and reliability of the platform are improved with the increasing number o... The working platforms supported with multiple extensible legs must be leveled before they come into operation.Although the supporting stiffness and reliability of the platform are improved with the increasing number of the supporting legs,the increased overdetermination of the multi-leg platform systems leads to leveling coupling problem among legs and virtual leg problem in which some of the supporting legs bear zero or quasi zero loads.These problems make it quite complex and time consuming to level such a multi-leg platform.Based on rigid body kinematics,an approximate equation is formulated to rapidly calculate the leg extension for leveling a rigid platform,then a proportional speed control strategy is proposed to reduce the unexpected platform distortion and leveling coupling between supporting legs.Taking both the load coupling between supporting legs and the elastic flexibility of the working platform into consideration,an optimal balancing legs’ loads(OBLL) model is firstly put forward to deal with the traditional virtual leg problem.By taking advantage of the concept of supporting stiffness matrix,a coupling extension method(CEM) is developed to solve this OBLL problem for multi-leg flexible platform.At the end,with the concept of supporting stiffness matrix and static transmissibility matrix,an optimal load balancing leveling method is proposed to achieve geometric leveling and legs’ loads balancing simultaneously.Three numerical examples are given out to illustrate the performance of proposed methods.This paper proposes a method which can effectively quantify all of the legs’ extension at the same time,achieve geometric leveling and legs’ loads balancing simultaneously.By using the proposed methods,the stability,precision and efficiency of auto-leveling control process can be improved. 展开更多
关键词 multi-leg platform overdetermined problem optimal balancing legs' loads supporting stiffness matrix static transmissibility matrix
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Some Symmetry Results for the A-Laplacian Equation via the Moving Planes Method
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作者 Zhongbo Fang Anna Wang 《Advances in Pure Mathematics》 2012年第6期363-366,共4页
In this paper, we are concerned with a positive solution of the non-homogeneous A-Laplacian equation in an open bounded connected domain. We use moving planes method to prove that the domain is a ball and the solution... In this paper, we are concerned with a positive solution of the non-homogeneous A-Laplacian equation in an open bounded connected domain. We use moving planes method to prove that the domain is a ball and the solution is radially symmetric. 展开更多
关键词 SYMMETRY A-Laplacian MOVING PLANES METHOD overdetermined BOUNDARY Value Problem
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Robust Parametric Modeling of Speech in Additive White Gaussian Noise
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作者 Abdelaziz Trabelsi Otmane Ait Mohamed Yves Audet 《Journal of Signal and Information Processing》 2015年第2期99-108,共10页
In estimating the linear prediction coefficients for an autoregressive spectral model, the concept of using the Yule-Walker equations is often invoked. In case of additive white Gaussian noise (AWGN), a typical parame... In estimating the linear prediction coefficients for an autoregressive spectral model, the concept of using the Yule-Walker equations is often invoked. In case of additive white Gaussian noise (AWGN), a typical parameter compensation method involves using a minimal set of Yule-Walker equation evaluations and removing a noise variance estimate from the principal diagonal of the autocorrelation matrix. Due to a potential over-subtraction of the noise variance, however, this method may not retain the symmetric Toeplitz structure of the autocorrelation matrix and thereby may not guarantee a positive-definite matrix estimate. As a result, a significant decrease in estimation performance may occur. To counteract this problem, a parametric modelling of speech contaminated by AWGN, assuming that the noise variance can be estimated, is herein presented. It is shown that by combining a suitable noise variance estimator with an efficient iterative scheme, a significant improvement in modelling performance can be achieved. The noise variance is estimated from the least squares analysis of an overdetermined set of p lower-order Yule-Walker equations. Simulation results indicate that the proposed method provides better parameter estimates in comparison to the standard Least Mean Squares (LMS) technique which uses a minimal set of evaluations for determining the spectral parameters. 展开更多
关键词 ARMA Model Noise Variance overdetermined PARAMETRIC Evaluation SINGULAR Value Representation LMS Technique Yule-Walker EQUATIONS
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Method of characteristics and first integrals for systems of quasi-linear partial differential equations of first order 被引量:1
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作者 HAN ChongKyu PARK JongDo 《Science China Mathematics》 SCIE CSCD 2015年第8期1665-1676,共12页
Given a set of independent vector fields on a smooth manifold, we discuss how to find a function whose zero-level set is invariant under the flows of the vector fields. As an application, we study the solvability of o... Given a set of independent vector fields on a smooth manifold, we discuss how to find a function whose zero-level set is invariant under the flows of the vector fields. As an application, we study the solvability of overdetermined partial differential equations: Given a system of quasi-linear PDEs of first order for one unknown function we find a necessary and sufficient condition for the existence of solutions in terms of the second jet of the coefficients. This generalizes to certain quasi-linear systems of first order for several unknown functions. 展开更多
关键词 overdetermined PDE system quasi-linear first order PDEs first integrals Pfai:fian systems Frobe-nius theorem
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Arbitrariness of the general solution of the partial differential equations and its applications
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作者 Ding Qi Zhang HongQing 《Science China Mathematics》 SCIE 2010年第7期1729-1739,共11页
Using the framework of formal theory of partial differential equations, we consider a method of computation of the bi-Hilbert polynomial (i.e. Hilbert polynomial in two variables). Furthermore, present an approach to ... Using the framework of formal theory of partial differential equations, we consider a method of computation of the bi-Hilbert polynomial (i.e. Hilbert polynomial in two variables). Furthermore, present an approach to compute the number of arbitrary functions of positive differential order in the general solution. Then, under the "AC=BD" model for mathematics mechanization developed by Hong-qing ZHANG, we present a method to reduce an overdetermined system to a well-determined one. As applications, the Maxwell equations and weakly overdetermined equations are considered. 展开更多
关键词 'AC=BD' model INVOLUTION HILBERT POLYNOMIAL ARBITRARINESS overdetermined
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CONVERGENCE OF NEWTON'S METHOD FOR SYSTEMS OF EQUATIONS WITH CONSTANT RANK DERIVATIVES
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作者 Xiubin Xu Chong Li 《Journal of Computational Mathematics》 SCIE EI CSCD 2007年第6期705-718,共14页
The convergence properties of Newton's method for systems of equations with constant rank derivatives are studied under the hypothesis that the derivatives satisfy some weak Lipschitz conditions. The unified converge... The convergence properties of Newton's method for systems of equations with constant rank derivatives are studied under the hypothesis that the derivatives satisfy some weak Lipschitz conditions. The unified convergence results, which include Kantorovich type theorems and Smale's point estimate theorems as special cases, are obtained. 展开更多
关键词 Newton's method overdetermined system Lipschitz condition with L average Convergence Rank.
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Two-Dimensional Parabolic Inverse Source Problem with Final Overdetermination in Reproducing Kernel Space
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作者 Wenyan WANG Masahiro YAMAMOTO Bo HAN 《Chinese Annals of Mathematics,Series B》 SCIE CSCD 2014年第3期469-482,共14页
A new method of the reproducing kernel Hilbert space is applied to a twodimensional parabolic inverse source problem with the final overdetermination. The exact and approximate solutions are both obtained in a reprodu... A new method of the reproducing kernel Hilbert space is applied to a twodimensional parabolic inverse source problem with the final overdetermination. The exact and approximate solutions are both obtained in a reproducing kernel space. The approximate solution and its partial derivatives are proved to converge to the exact solution and its partial derivatives, respectively. A technique is proposed to improve some existing methods. Numerical results show that the method is of high precision, and confirm the robustness of our method for reconstructing source parameter. 展开更多
关键词 Inverse source problem Final overdetermination Parabolic equation Reproducing kernel
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