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The Equivalence Theorem of Appoximation for Two-dimensional Baskakov Operators
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作者 FENG Guo 《Chinese Quarterly Journal of Mathematics》 CSCD 2009年第1期27-34,共8页
In this paper, we study the convergence rate of two-dimensional Baakakov operators with Jacobi-weights and the approximation equivalence theorem is obtained, making use of multivariate decompose skills and results of ... In this paper, we study the convergence rate of two-dimensional Baakakov operators with Jacobi-weights and the approximation equivalence theorem is obtained, making use of multivariate decompose skills and results of one-dimensional Baskakov operators. 展开更多
关键词 Baskakov operators Jacobi-weights multivariate decompose equivalence theorem
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EQUIVALENCE THEOREM ON WEIGHTED SIMULTANEOUS L-APPROXIMATION BY MEANS OF SZASZ-KANTOROVICH OPERATORS AND BASKAKOV-KANTOROVICH OPERATORS
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作者 Li Bingzheng Zhejiang University, China 《Analysis in Theory and Applications》 1994年第1期76-87,共12页
The intention of this paper is to give direct and converse results on weighted simultaneous approximation by means of Sz(?)sz-Kantorovich operators and Baskakov-Kantorovich operators in L_p-norms using the weighted Di... The intention of this paper is to give direct and converse results on weighted simultaneous approximation by means of Sz(?)sz-Kantorovich operators and Baskakov-Kantorovich operators in L_p-norms using the weighted Ditzian-Totik modulus of smoothness. 展开更多
关键词 equivalence theorem ON WEIGHTED SIMULTANEOUS L-APPROXIMATION BY MEANS of SZASZ-KANTOROVICH OPERATORS AND BASKAKOV-KANTOROVICH OPERATORS Math APPI 七声 Zr
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Helmholtz Theorems, Gauge Transformations, General Covariance and the Empirical Meaning of Gauge Conditions
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作者 Andrew Chubykalo Augusto Espinoza Rolando Alvarado Flores 《Journal of Modern Physics》 2016年第9期1021-1044,共24页
It is well known that the use of Helmholtz decomposition theorem for static vector fields , when applied to the time dependent vector fields , which represent the electromagnetic field, allows us to obtain instan... It is well known that the use of Helmholtz decomposition theorem for static vector fields , when applied to the time dependent vector fields , which represent the electromagnetic field, allows us to obtain instantaneous-like solutions all along . For this reason, some people thought (see e.g. [1] and references therein) that the Helmholtz theorem cannot be applied to time dependent vector fields and some modification is wanted in order to get the retarded solutions. However, the use of the Helmholtz theorem for static vector fields is correct even for time dependent vector fields (see, e.g. [2]), so a relation between the solutions was required, in such a way that a retarded solution can be transformed in an instantaneous one, and conversely. On this paper we want to suggest, following most of the time the mathematical formalism of Woodside in [3], that: 1) there are many Helmholtz decompositions, all equally consistent, 2) each one is naturally related to a space-time structure, 3) when we use the Helmholtz decomposition for the electromagnetic potentials it is equivalent to a gauge transformation, 4) there is a natural methodological criterion for choosing the gauge according to the structure postulated for a global space-time, 5) the Helmholtz decomposition is the manifestation at the level of the fields that a gauge is involved. So, when we relate the retarded solution to the instantaneous one what we do is to change the gauge and the space-time. And, if the Helmholtz decompositions are related to a space-time structure, and are equivalent to gauge transformations, each gauge transformation is natural for a specific space-time. In this way, a Helmholtz decomposition for Euclidean space is equivalent to the Coulomb gauge and a Helmholtz decomposition for the Minkowski space is equivalent to the Lorenz gauge. This leads us to consider that the theories defined by different gauges may be mathematically equivalent, because they can be related by means of a gauge transformation, but they are not empirically equivalent, because they have quite different observational consequences due to the different space-time structure involved. 展开更多
关键词 Helmholtz theorem Gauge transformations Space-Time transformations Symmetries of Differential Equations Underdetermination of Systems of Differential Equations Natural Covariance
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Approach to a Proof of the Riemann Hypothesis by the Second Mean-Value Theorem of Calculus 被引量:3
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作者 Alfred Wünsche 《Advances in Pure Mathematics》 2016年第13期972-1021,共51页
By the second mean-value theorem of calculus (Gauss-Bonnet theorem) we prove that the class of functionswith an integral representation of the form  with a real-valued function which is non-increasing a... By the second mean-value theorem of calculus (Gauss-Bonnet theorem) we prove that the class of functionswith an integral representation of the form  with a real-valued function which is non-increasing and decreases in infinity more rapidly than any exponential functions , possesses zeros only on the imaginary axis. The Riemann zeta function  as it is known can be related to an entire functionwith the same non-trivial zeros as . Then after a trivial argument displacement we relate it to a function  with a representation of the form  where  is rapidly decreasing in infinity and satisfies all requirements necessary for the given proof of the position of its zeros on the imaginary axis z=iy by the second mean-value theorem. Besides this theorem we apply the Cauchy-Riemann differential equation in an integrated operator form derived in the Appendix B. All this means that we prove a theorem for zeros of  on the imaginary axis z=iy for a whole class of function  which includes in this way the proof of the Riemann hypothesis. This whole class includes, in particular, also the modified Bessel functions  for which it is known that their zeros lie on the imaginary axis and which affirms our conclusions that we intend to publish at another place. In the same way a class of almost-periodic functions to piece-wise constant non-increasing functions  belong also to this case. At the end we give shortly an equivalent way of a more formal description of the obtained results using the Mellin transform of functions with its variable substituted by an operator. 展开更多
关键词 Riemann Hypothesis Riemann Zeta Function Xi Function Gauss-Bonnet theorem Mellin Transformation
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Convolution Theorem of Fractional Fourier Transformation Derived by Representation Transformation in Quantum Mechancis 被引量:1
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作者 FAN Hong-Yi HAO Ren LU Hai-Liang 《Communications in Theoretical Physics》 SCIE CAS CSCD 2008年第9期611-614,共4页
Based on our previous paper (Commun.Theor.Phys.39 (2003) 417) we derive the convolution theoremof fractional Fourier transformation in the context of quantum mechanics,which seems a convenient and neat way.Generalizat... Based on our previous paper (Commun.Theor.Phys.39 (2003) 417) we derive the convolution theoremof fractional Fourier transformation in the context of quantum mechanics,which seems a convenient and neat way.Generalization of this method to the complex fractional Fourier transformation case is also possible. 展开更多
关键词 fractional Fourier transformation convolution theorem quantum mechanical representation transform
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STUDY OF THE EQUIVALENT THEOREM OF GENERALIZED VARIATIONAL PRINCIPLES IN ELASTICITY
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作者 张国清 余建星 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2004年第3期347-357,共11页
The relations of all generalized variational principles in elasticity are studied by employing the invariance theorem of field theory. The infinitesimal scale transformation in field theory was employed to investigate... The relations of all generalized variational principles in elasticity are studied by employing the invariance theorem of field theory. The infinitesimal scale transformation in field theory was employed to investigate the equivalent theorem. Among the results found particularly interesting are those related to that all generalized variational principles in elasticity are equal to each other. Also studied result is that only two variables are independent in the functional and the stress-strain relation is the variational constraint condition for all generalized variational principles in elasticity. This work has proven again the conclusion of Prof. Chien Wei-zang. 展开更多
关键词 ELASTICITY generalized variational principle equivalent theorem scale transformation INVARIANCE
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THE SPACES OF CESRO ALMOST CONVERGENT SEQUENCES AND CORE THEOREMS
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作者 Kuddusi Kayaduman Mehmet Sengönül 《Acta Mathematica Scientia》 SCIE CSCD 2012年第6期2265-2278,共14页
As known, the method to obtain a sequence space by using convergence field of an infinite matrix is an old method in the theory of sequence spaces. However, the study of convergence field of an infinite matrix in the ... As known, the method to obtain a sequence space by using convergence field of an infinite matrix is an old method in the theory of sequence spaces. However, the study of convergence field of an infinite matrix in the space of almost convergent sequences is so new (see [15]). The purpose of this paper is to introduce the new spaces ^ ~f and fo consisting of all sequences whose Ceshro transforms of order one are in the spaces f and ^ ~ f0, respectively. Also, in this paper, we show that ^ ~f and ^ ~f0 are linearly isomorphic to the spaces f and f0, respectively. The β- and γ-duals of the spaces ^ ~f and 2% are computed. Furthermore, the classes (^ ~f: μ) and (μ : f) of infinite matrices are characterized for any given sequence space μ, and determined the necessary and sufficient conditions on a matrix A to satisfy Bc-core(Ax) K-core(x), K-core(Ax) Bg-core(x), Bc-core(Ax) Be-core(x), Bc-core(Ax) t-core(x) for all x ∈ t∞. 展开更多
关键词 almost convergence matrix domain of a sequence space β- and γ-duals andmatrix transformations core theorems ISOMORPHISM
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Equivalence Problem of the PainlevéEquations
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作者 Sopita Khamrod 《Advances in Pure Mathematics》 2013年第2期297-303,共7页
The manuscript is devoted to the equivalence problem of the Painlevé equations. Conditions which are necessary and sufficient for second-order ordinary differential equations y″=F (x ,y, y′) to be equivalent to... The manuscript is devoted to the equivalence problem of the Painlevé equations. Conditions which are necessary and sufficient for second-order ordinary differential equations y″=F (x ,y, y′) to be equivalent to the first and second Painlevé equation under a general point transformation are obtained. A procedure to check these conditions is found. 展开更多
关键词 equivalence PROBLEM Painlevé EQUATIONS POINT TRANSFORMATION
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The Conditions of Equivalence of a Class Germs of C~∞ Functions on Banach Spaces
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作者 CEN Yan-bin LIU Wen-wu CEN Yi-gang 《Chinese Quarterly Journal of Mathematics》 CSCD 2011年第2期223-228,共6页
In this paper,we prove the converse of gem is right equivalent is also true in[1] and[2],obtain the necessary and sufficient conditions of equivalence of a class gems of C∞ function on Banach spaces.
关键词 Banach space converse theorem Frodholm gem right equivalent implicit function
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ON THE DECOMPOSITION OF COMPLEX VECTOR SPACES AND THE JORDAN CANONICAL FORM OF COMPLEX LINEAR TRANSFORMATIONS
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作者 肖衡 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1994年第11期997-1003,共7页
New objects characterizing the structure of complex linear transformations areintroduced. These new objects yield a new result for the decomposition of complexvector spaces relative to complex lrnear transformations a... New objects characterizing the structure of complex linear transformations areintroduced. These new objects yield a new result for the decomposition of complexvector spaces relative to complex lrnear transformations and provide all Jordan basesby which the Jordan canonical form is constructed. Accordingly, they can result in thecelebrated Jordan theorem and the third decomposition theorem of space directly. and,moreover, they can give a new deep insight into the exquisite and subtle structure ofthe Jordan form. The latter indicates that the Jordan canonical form of a complexlinear transformation is an invariant structure associated with double arbitrary. choices. 展开更多
关键词 complex vector space complex linear transformation. decompo-sition theorems. Jordan canonical form
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Investigation of Probability Generating Function in an Interdependent <i>M/M/</i>1:(∞;GD) Queueing Model with Controllable Arrival Rates Using Rouche’s Theorem
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作者 Vishwa Nath Maurya 《Open Journal of Optimization》 2012年第2期34-38,共5页
Present paper deals a M/M/1:(∞;GD) queueing model with interdependent controllable arrival and service rates where- in customers arrive in the system according to poisson distribution with two different arrivals rate... Present paper deals a M/M/1:(∞;GD) queueing model with interdependent controllable arrival and service rates where- in customers arrive in the system according to poisson distribution with two different arrivals rates-slower and faster as per controllable arrival policy. Keeping in view the general trend of interdependent arrival and service processes, it is presumed that random variables of arrival and service processes follow a bivariate poisson distribution and the server provides his services under general discipline of service rule in an infinitely large waiting space. In this paper, our central attention is to explore the probability generating functions using Rouche’s theorem in both cases of slower and faster arrival rates of the queueing model taken into consideration;which may be helpful for mathematicians and researchers for establishing significant performance measures of the model. Moreover, for the purpose of high-lighting the application aspect of our investigated result, very recently Maurya [1] has derived successfully the expected busy periods of the server in both cases of slower and faster arrival rates, which have also been presented by the end of this paper. 展开更多
关键词 Interdependent QUEUEING Model BIVARIATE Poisson Process Controllable Arrival Rates Probability Generating Function Laplace Transform Rouche’s theorem Performance Measures
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Characterization Theorem of Generalized Operators
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作者 Mahmmoud Salih Sulieman Jomah 《Journal of Applied Mathematics and Physics》 2018年第7期1434-1442,共9页
In this paper, by using the W-transform of an operator on white noise functionals, we establish a general characterization theorem for operators on white noise functionals in term of growth condition. We also discuss ... In this paper, by using the W-transform of an operator on white noise functionals, we establish a general characterization theorem for operators on white noise functionals in term of growth condition. We also discuss convergence of operator sequences. 展开更多
关键词 WHITE Noise FUNCTIONALS W-Transform S-TRANSFORM Characterization theorem
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基于El-Nabulsi分数阶模型的广义Birkhoff系统Noether对称性研究 被引量:9
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作者 张毅 丁金凤 《南京理工大学学报》 EI CAS CSCD 北大核心 2014年第3期409-413,共5页
为了进一步揭示力学系统的对称性与守恒量之间的内在关系,基于El-Nabulsi分数阶模型提出并研究了广义Birkhoff系统的Noether定理。首先,提出分数阶广义El-Nabulsi-PfaffBirkhoff原理,建立广义El-Nabulsi-Birkhoff方程。其次,基于El-Nabu... 为了进一步揭示力学系统的对称性与守恒量之间的内在关系,基于El-Nabulsi分数阶模型提出并研究了广义Birkhoff系统的Noether定理。首先,提出分数阶广义El-Nabulsi-PfaffBirkhoff原理,建立广义El-Nabulsi-Birkhoff方程。其次,基于El-Nabulsi-Pfaff作用量在无限小变换下的不变性,给出广义Birkhoff系统Noether对称性的定义和判据。最后,提出广义Birkhoff系统的Noether定理。该文研究结果可进一步应用于完整和非完整约束系统。 展开更多
关键词 力学系统 对称性 守恒量 El-Nabulsi分数阶模型 广义BIRKHofF系统 NOEtheR定理 无限小变换 完整约束系统 非完整约束系统
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The Noether's Theory of Constrained Birkhoffian System
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作者 尚玫 梅凤翔 《Journal of Beijing Institute of Technology》 EI CAS 1997年第3期221-228,共8页
By using the synmeby and the qusi-symmetry of the infinitesimal transformation of the transformation group G1 and by imposing restrictions of constraints on the transformation, the Noether's theory of constrained ... By using the synmeby and the qusi-symmetry of the infinitesimal transformation of the transformation group G1 and by imposing restrictions of constraints on the transformation, the Noether's theory of constrained Birkhoffian system has been established. The theory includes the generalized Noether's theorem obtaining the first integrals from the known symmetry and quasi-symmetry and its inverse obtaining the corresponding symmetry and quasi-symmetry from the known first integrals for the systerm. 展开更多
关键词 .Birkhoffian system: constraint TRANSFORMATION conservation law Noether's theorem
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The Numerical Scheme Development of a Simplified Frozen Soil Model 被引量:5
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作者 李倩 孙菽芬 戴秋丹 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2009年第5期940-950,共11页
In almost all frozen soil models used currently, three variables of temperature, ice content and moisture content are used as prognostic variables and the rate term, accounting for the contribution of the phase change... In almost all frozen soil models used currently, three variables of temperature, ice content and moisture content are used as prognostic variables and the rate term, accounting for the contribution of the phase change between water and ice, is shown explicitly in both the energy and mass balance equations. The models must be solved by a numerical method with an iterative process, and the rate term of the phase change needs to be pre-estimated at the beginning in each iteration step. Since the rate term of the phase change in the energy equation is closely related to the release or absorption of the great amount of fusion heat, a small error in the rate term estimation will introduce greater error in the energy balance, which will amplify the error in the temperature calculation and in turn, cause problems for the numerical solution convergence. In this work, in order to first reduce the trouble, the methodology of the variable transformation is applied to a simplified frozen soil model used currently, which leads to new frozen soil scheme used in this work. In the new scheme, the enthalpy and the total water equivalent are used as predictive variables in the governing equations to replace temperature, volumetric soil moisture and ice content used in many current models. By doing so, the rate terms of the phase change are not shown explicitly in both the mass and energy equations and its pre-estimation is avoided. Secondly, in order to solve this new scheme more functionally, the development of the numerical scheme to the new scheme is described and a numerical algorithm appropriate to the numerical scheme is developed. In order to evaluate the new scheme of the frozen soil model and its relevant algorithm, a series of model evaluations are conducted by comparing numerical results from the new model scheme with three observational data sets. The comparisons show that the results from the model are in good agreement with these data sets in both the change trend of variables and their magnitude values, and the new scheme, together with the algorithm, is more efficient and saves more computer time. 展开更多
关键词 simplified frozen soil model variable transformation enthalpy and total water equivalent numerical algorithm model validation
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Application of the method of equivalent edge currents to composite scattering from the cone-cylinder above a dielectric rough sea surface 被引量:3
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作者 郭立新 王蕊 吴振森 《Chinese Physics B》 SCIE EI CAS CSCD 2010年第4期247-258,共12页
Compared with scattering from a rough surface only, composite scattering from a target above a rough surface has become so practical that it is a subject of great interest. At present, this problem has been solved by ... Compared with scattering from a rough surface only, composite scattering from a target above a rough surface has become so practical that it is a subject of great interest. At present, this problem has been solved by some numerical methods which will produce an enormous calculation amount. In order to overcome this shortcoming, the reciprocity theorem (RT) and the method of equivalent edge currents (MEC) are used in this paper. Due to the advantage of RT, the difficulty in computing the secondary scattered fields is reduced. Simultaneously, MEC, a high-frequency method with edge diffraction considered, is used to calculate the scattered field from the cone-cylinder target with a high accuracy and efficiency. The backscattered field and the polarization currents of the rough sea surface are evaluated by the Kirchhoff approximation (KA) method and physical optics (PO) method, respectively. The effects of the backscattering radar cross section (RCS) and the Doppler spectrum on the size of the target and the windspeed of the sea surface for different incident angles are analysed in detail. 展开更多
关键词 method of equivalent edge currents reciprocity theorem cone-cylinder rough sea surface electromagnetic scattering
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Theory and application of equivalent transformation relationships between plane wave and spherical wave 被引量:2
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作者 Wang Yao Yang Zailin +1 位作者 Zhang Jianwei Yang Yong 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2017年第4期773-782,共10页
Based on the governing equations and the equivalent models, we propose an equivalent transformation relationships between a plane wave in a one-dimensional medium and a spherical wave in globular geometry with radiall... Based on the governing equations and the equivalent models, we propose an equivalent transformation relationships between a plane wave in a one-dimensional medium and a spherical wave in globular geometry with radially inhomogeneous properties. These equivalent relationships can help us to obtain the analytical solutions of the elastodynamic issues in an inhomogeneous medium. The physical essence of the presented equivalent transformations is the equivalent relationships between the geometry and the material properties. It indicates that the spherical wave problem in globular geometry can be transformed into the plane wave problem in the bar with variable property fields, and its inverse transformation is valid as well. Four different examples of wave motion problems in the inhomogeneous media are solved based on the presented equivalent relationships. We obtain two basic analytical solution forms in Examples I and II, investigate the reflection behavior of inhomogeneous half-space in Example III, and exhibit a special inhomogeneity in Example IV, which can keep the traveling spherical wave in constant amplitude. This study implies that our idea makes solving the associated problem easier. 展开更多
关键词 elastodynamic issue equivalent transformation relationship governing equation inhomogeneous medium
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Design and Analysis of Transmitter Charge Switch Assembly Load on Weather Radar Test Platform 被引量:1
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作者 Shi Zheng Guan Wang +1 位作者 Xingyou Huang Guilin Liu 《Journal of Geoscience and Environment Protection》 2018年第10期51-58,共8页
This paper provides a new method for designing the load of transmitters switch components on provincial radar test platform. Based on the calculation of the specific parameters related to the actual charge switch comp... This paper provides a new method for designing the load of transmitters switch components on provincial radar test platform. Based on the calculation of the specific parameters related to the actual charge switch components, the load-related data model is obtained, the simulation is carried out, and the results are consistent with the actual test results. Through the theoretical numerical analysis of the load of the charging switch components of the transmitter device in the new generation of weather radar maintenance test platform, radar maintenance personnel at all levels can deepen the thorough understanding of the CINRAD/SA transmitter and have some enlightenment and improvement on the maintenance guarantee ability of the new generation of weather radar. 展开更多
关键词 Weather Radar CHARGING SWITCH ASSEMBLY CHARGING Equivalent LOAD CHARGING Transformer
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Computation of the Smith Form for Multivariate Polynomial Matrices Using Maple 被引量:1
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作者 Mohamed Salah Boudellioua 《American Journal of Computational Mathematics》 2012年第1期21-26,共6页
In this paper we show how the transformations associated with the reduction to the Smith form of some classes of mul-tivariate polynomial matrices are computed. Using a Maple implementation of a constructive version o... In this paper we show how the transformations associated with the reduction to the Smith form of some classes of mul-tivariate polynomial matrices are computed. Using a Maple implementation of a constructive version of the Quillen-Suslin Theorem, we present two algorithms for the reduction to a particular Smith form often associated with the simplification of linear systems of multidimensional equations. 展开更多
关键词 SMITH FORM Unimodular equivalence Quillen-Suslin theorem MAPLE
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The Functional Gradient Description Method of Space Coordinate Transformation 被引量:2
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作者 Pengshuo DUAN Genyou LIU +2 位作者 Youliang GONG Xiaoguang HAO Nazi WANG 《Journal of Geodesy and Geoinformation Science》 2019年第1期66-71,共6页
The 3-dimension coordinate datum transformation is very important in geomatics.Generally,there are small angle coordinate transformation model (i.e.,Bursa model,et al) and large angle coordinate transformation model (... The 3-dimension coordinate datum transformation is very important in geomatics.Generally,there are small angle coordinate transformation model (i.e.,Bursa model,et al) and large angle coordinate transformation model (i.e.,Rodrigo matrix model,et al).However,these papers only focus on the fixed and static situation regardless of the small or large angle.This paper proposes the conception of coordinate transformation gradient field,which can realize the space coordinate transformation from small angle to arbitrary angle,and from static to dynamical.Based on the equivalent characteristics of the unit quaternion rotation matrix and the Rodrigo matrix,through studying the mathematical relationship between the spatial coordinate transformation and the functional gradient,we derive a functional gradient expression of the arbitrary transformation formula in space.The study shows that the essence of spatial coordinate transformation is a kind of potential field mathematically.This potential field conception can unify all the space coordinate transformations.It is the theoretical foundation for the further study of time continuous space coordinate transformation,and this study gives a new solution for the attitude determination of motion carriers. 展开更多
关键词 spatial COORDINATE TRANSFORMATION functional GRADIENT field COMPLETE equivalence
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