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Stability of the MGS-like elimination method for equality constrained least squares problems 被引量:1
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作者 刘巧华 《Journal of Shanghai University(English Edition)》 CAS 2009年第3期213-218,共6页
This paper proves that the weighting method via modified Gram-Schmidt(MGS) for solving the equality constrained least squares problem in the limit is equivalent to the direct elimination method via MGS(MGS-eliminat... This paper proves that the weighting method via modified Gram-Schmidt(MGS) for solving the equality constrained least squares problem in the limit is equivalent to the direct elimination method via MGS(MGS-elimination method). By virtue of this equivalence, the backward and forward roundoff error analysis of the MGS-elimination method is proved. Numerical experiments are provided to verify the results. 展开更多
关键词 equality constrained least squares elimination method modified Gram-Schmidt (MGS) column pivoting roundoff error
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Role of oral-fluid based measles diagnostic methods for measles global elimination
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作者 Wondatir Nigatu Antoine Nsabimana 《World Journal of Experimental Medicine》 2013年第4期87-99,共13页
Measles eradication is biologically feasible. There is an availability of a safe, effective and inexpensive vaccine; a proven elimination strategy; high Local demand; and an effective global partnership and initiative... Measles eradication is biologically feasible. There is an availability of a safe, effective and inexpensive vaccine; a proven elimination strategy; high Local demand; and an effective global partnership and initiative to support vaccination. Measles eradication is a cost-effective scenario and a good investment to avoid expensive epidemics and save those children die due to measles. Laboratory investigations are indispensable to monitor the progress of measles elimination. This role will require the development of more sensitive diagnostic methods suitable for diagnosis and surveillance, genetic analysis of measles strains and a technology which is transferable worldwide. Measles diagnosis relies increasingly on serological tests. The practical utility of oral-fluid methods(antibody and genetic) in evaluating and refining measles immunization programs would,additionally, provide support for a global surveillance initiative. The utility of in a population survey, in a vaccine sero-conversion study and application in molecular epidemiological use is demonstrated in this review. It is to be hoped that this review will assist in the wider uptake and acceptance of methodology in both developed and developing country situation. More research needed for further evaluation of a recently developed point-of-care test for measles diagnosis: detection of measles-specific Ig M antibodies and viral nucleic acid for wider use oral-fluid methodology. There is a strong case and imperative for the promotion of methods by World Health Organization in its global program of control/eradication of measles over the coming decade. 展开更多
关键词 MEASLES elimination Oral-fluid test methods LABORATORY DIAGNOSIS
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Symmetry Classification of Partial Differential Equations Based on Wu's Method
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作者 TIAN Yi WAN Jianxiong 《Journal of Donghua University(English Edition)》 CAS 2021年第2期187-192,共6页
Lie algorithm combined with differential form Wu's method is used to complete the symmetry classification of partial differential equations(PDEs)containing arbitrary parameter.This process can be reduced to solve ... Lie algorithm combined with differential form Wu's method is used to complete the symmetry classification of partial differential equations(PDEs)containing arbitrary parameter.This process can be reduced to solve a large system of determining equations,which seems rather difficult to solve,then the differential form Wu's method is used to decompose the determining equations into a series of equations,which are easy to solve.To illustrate the usefulness of this method,we apply it to some test problems,and the results show the performance of the present work. 展开更多
关键词 Lie algorithm differential form wu's method determining equation symmetry classification partial differential equation(PDE)
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The Exact Formulation of the Inverse of the Tridiagonal Matrix for Solving the 1D Poisson Equation with the Finite Difference Method 被引量:2
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作者 Serigne Bira Gueye 《Journal of Electromagnetic Analysis and Applications》 2014年第10期303-308,共6页
A new method for solving the 1D Poisson equation is presented using the finite difference method. This method is based on the exact formulation of the inverse of the tridiagonal matrix associated with the Laplacian. T... A new method for solving the 1D Poisson equation is presented using the finite difference method. This method is based on the exact formulation of the inverse of the tridiagonal matrix associated with the Laplacian. This is the first time that the inverse of this remarkable matrix is determined directly and exactly. Thus, solving 1D Poisson equation becomes very accurate and extremely fast. This method is a very important tool for physics and engineering where the Poisson equation appears very often in the description of certain phenomena. 展开更多
关键词 1D POISSON Equation Finite Difference method TRIDIAGONAL Matrix INVERSION Thomas Algorithm GAUSSIAN elimination Potential Problem
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Analysis of the Invariance and Generalizability of Multiple Linear Regression Model Results Obtained from Maslach Burnout Scale through Jackknife Method
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作者 Tolga Zaman Kamil Alakus 《Open Journal of Statistics》 2015年第7期645-651,共7页
The purpose of this study was to examine the burnout levels of research assistants in Ondokuz Mayis University and to examine the results of multiple linear regression model based on the results obtained from Maslach ... The purpose of this study was to examine the burnout levels of research assistants in Ondokuz Mayis University and to examine the results of multiple linear regression model based on the results obtained from Maslach Burnout Scale with Jackknife Method in terms of validity and generalizability. To do this, a questionnaire was given to 11 research assistants working at Ondokuz Mayis University and the burnout scores of this questionnaire were taken as the dependent variable of the multiple linear regression model. The variable of burnout was explained with the variables of age, weekly hours of classes taught, monthly average credit card debt, numbers of published articles and reports, gender, marital status, number of children and the departments of the research assistants. Dummy variables were assigned to the variables of gender, marital status, number of children and the departments of the research assistants and thus, they were made quantitative. The significance of the model as a result of multiple linear regressions was examined through backward elimination method. After this, for the five explanatory variables which influenced the variable of burnout, standardized model coefficients and coefficients of determination, and 95% confidence intervals of these values were estimated through Jackknife Method and the generalizability of the parameter estimation results of these variables on population was researched. 展开更多
关键词 JACKKNIFE method INVARIANCE GENERALIZABILITY Maslach BURNOUT SCALE Multiple Linear Regression Backward elimination method
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A Comprehensive Overview of the ELECTRE Method in Multi-Criteria Decision-Making 被引量:1
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作者 Hamed Taherdoost Mitra Madanchian 《Journal of Management Science & Engineering Research》 2023年第2期5-16,共12页
The ELECTRE(ELimination Et Choix Traduisant la REalite)method has gained widespread recognition as one of the most effective multi-criteria decision-making(MCDM)methods.Its versatility allows it to be applied in a wid... The ELECTRE(ELimination Et Choix Traduisant la REalite)method has gained widespread recognition as one of the most effective multi-criteria decision-making(MCDM)methods.Its versatility allows it to be applied in a wide range of areas such as engineering,economics,business,environmental management and many others.This paper aims to provide an overview of the ELECTRE method,including its fundamental concepts,applications,advantages,and limitations.At its core,the ELECTRE method is an outranking family of MCDM techniques,which allows for the direct comparison of alternatives based on a set of criteria.The method takes into account the preferences and importance of decision-makers and generates a ranking of the alternatives based on their relative strengths and weaknesses.The ELECTRE method is a powerful tool for decision-making,and its applicability to a wide range of fields demonstrates its versatility and adaptability.By understanding its concepts,applications,merits,and demerits,decision-makers can use the ELECTRE method to make informed and effective decisions in a variety of contexts. 展开更多
关键词 Decision making Multi criteria decision making ELECTRE method elimination Et Choix Traduisant la REalite method Multi attribute decision making
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A type of inverter power supply based on harmonic elimination PWM control
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作者 张开如 邢呈呈 刘相楠 《Journal of Measurement Science and Instrumentation》 CAS 2013年第1期68-73,共6页
In order to output sine wave with small degree of distortion and improve stability,a type of inverter power supply is designed based on harmonic elimination pulse-width modulation(PWM)control.The rectifier and filter ... In order to output sine wave with small degree of distortion and improve stability,a type of inverter power supply is designed based on harmonic elimination pulse-width modulation(PWM)control.The rectifier and filter are added to input circuit of the inverter.Single-phrase full-bridge inverter performs the function of converting direct current into alternating current(DC/AC).In the control circuit,single chip micyoco(SCM)AT89C2051 is used for main control chip to accomplish the hardware design of the control system.A given value of output frequency of the inverter is input in the way of coding.According to the output frequency code which is read,SCM AT89C2051 defined harmonic elimination PWM control data which will be selected.Through internal timing control,the switches are switched under this provision of PWM control data.Then the driving signals of the switches in the inverter are output from I/O of SCM AT89C2051 to realize harmonic elimination PWM control.The results show that adding Newton homotopic algorithm of harmonic elimination PWM control to corresponding software of the control system can make the quality of output voltage of the inverter higher and it will have broad application prospects. 展开更多
关键词 inverter power supply pulse-width modulation(PWM) harmonic elimination PWM control Newton homotopic continuation method
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Independent continuous mapping for topological optimization of frame structures 被引量:10
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作者 Yunkang Sui Jiazheng Du Yingqiao Guo 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2006年第6期611-619,共9页
Based on the Independent Continuous Mapping method (ICM), a topological optimization model with continuous topological variables is built by introducing three filter functions for element weight, element allowable s... Based on the Independent Continuous Mapping method (ICM), a topological optimization model with continuous topological variables is built by introducing three filter functions for element weight, element allowable stress and element stiffness, which transform the 0-1 type discrete topological variables into continuous topological variables between 0 and 1. Two methods for the filter functions are adopted to avoid the structural singularity and recover falsely deleted elements: the weak material element method and the tiny section element method. Three criteria (no structural singularity, no violated constraints and no change of structural weight) are introduced to judge iteration convergence. These criteria allow finding an appropriate threshold by adjusting a discount factor in the iteration procedure. To improve the efficiency, the original optimization model is transformed into a dual problem according to the dual theory and solved in its dual space. By using MSC/Nastran as the structural solver and MSC/Patran as the developing platform, a topological optimization software of frame structures is accomplished. Numerical examples show that the ICM method is very efficient for the topological optimization of frame structures. 展开更多
关键词 Frame structures Topological optimization ICM method Filter functions Element elimination
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Study on the variation characteristics of the geoelectric field preceding earthquakes 被引量:7
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作者 MA Qin-zhong(马钦忠) +5 位作者 FENG Zhi-sheng(冯志生) SONG Zhi-ping(宋治平) ZHAO Wei-guo(赵卫国) 《Acta Seismologica Sinica(English Edition)》 CSCD 2004年第3期334-343,共10页
Earthquake events occurred in Nantong, Jiangsu Province on Nov. 3, and Dec. 25, 2001 in which the biggest mag-nitudes were ML=3.8 and ML=4.1, respectively. This paper firstly explains the principle of the eliminating ... Earthquake events occurred in Nantong, Jiangsu Province on Nov. 3, and Dec. 25, 2001 in which the biggest mag-nitudes were ML=3.8 and ML=4.1, respectively. This paper firstly explains the principle of the eliminating noise method by the multi-dipole observation system of geoelectric field. Then based on the observation data of the multi-dipole observation system obtained by ZD9A telluric current monitors installed in Chongming and Nanjing stations, we study the abnormal variation of the geoelectric field preceding the earthquakes. The study shows that: a) Eliminating noise method of multi-dipole observation is an excellent method by which many kinds of geoelec-tric field noises can be eliminated successfully and the geoelectric precursor information can be recognized; b) The geoelectric precursor signals for the events were recorded on the NS and NE dipoles in Chongming station 42 days, 20 days and 2 days before the earthquakes respectively, in which the station is near the epicenter, and the longest time of persisting period was 9 days. The abnormal variation signals of geoelectric field observed in Nanjing sta-tion are all the noises but not the seismic electric signals, in which the station is not near the epicenter; c) Dipole distribution method of common electrode is not good in the multi-dipole observation system of the geoelectric field. 展开更多
关键词 EARTHQUAKE geoelectric field multi-dipole observation system eliminating noise method
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Kinematics Analysis of Mechanisms Based on Virtual Assembly 被引量:6
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作者 ZHANG Zhixian LIU Jianhua NING Ruxin 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2010年第6期748-757,共10页
Currently, virtual assembly technology has attracted increasing attention due to considerations of solving assembly problems in virtual environment before actual assembly in manufactory. Previous studies on kinematic ... Currently, virtual assembly technology has attracted increasing attention due to considerations of solving assembly problems in virtual environment before actual assembly in manufactory. Previous studies on kinematic analysis of mechanism only aim at analyzing motion law of single mechanism, but can not simulate the multi-mechanisms motion process at the same time, let alone simulating the automatic assembly process of products in a whole assembly workshop. In order to simulate the assembly process of products in an assembly workshop and provide effective data for analyzing mechanical performance after finishing assembly simulation in virtual environment, this study investigates the kinematics analysis of mechanisms based on virtual assembly. Firstly, in view of the same function of the kinematic pairs and the assembly constraints on restricting the motion of components (subassembly or part), the method of identifying kinematic pairs automatically based on assembly constraints is presented. The information of kinematic pairs can be obtained through calculating the constraint degree of the assembly constraints. Secondly, the incidence matrix eliminating element method is proposed in order to search the information and establish the models of mechanisms automatically after finishing assembly simulation in virtual environment. Both methods have important significance for reducing the workload of pretreatment and promoting the level of automation of kinematics analysis. Finally, the method of kinematics analysis of mechanisms is presented. Based on Descartes coordinates, three types of kinematics equations are formed. The parameters, like displacement, velocity, and acceleration, can be obtained by solving these equations. All these data are important to analyze mechanical performance. All the methods are implemented and validated in the prototype system virtual assembly process planning(VAPP). The mechanism models are established and simulated in the VAPP system, and the result curves are shown accurately. The proposed kinematics analysis of mechanisms based on virtual assembly provides an effective method for simulating product assembly process automatically and analyzing mechanical performance after finishing assembly simulation. 展开更多
关键词 virtual assembly assembly constraint constraint degree eliminating element method kinematics equations kinematics analysis
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Kinematic Solution of Spherical Stephenson-Ⅲ Six-bar Mechanism 被引量:3
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作者 LIU Yanfang YANG Suixian 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2013年第5期851-860,共10页
A closed-form solution can be obtained for kinematic analysis of spatial mechanisms by using analytical method.However,extra solutions would occur when solving the constraint equations of mechanism kinematics unless t... A closed-form solution can be obtained for kinematic analysis of spatial mechanisms by using analytical method.However,extra solutions would occur when solving the constraint equations of mechanism kinematics unless the constraint equations are established with a proper method and the solving approach is appropriate.In order to obtain a kinematic solution of the spherical Stephenson-III six-bar mechanism,spherical analytical theory is employed to construct the constraint equations.Firstly,the mechanism is divided into a four-bar loop and a two-bar unit.On the basis of the decomposition,vectors of the mechanism nodes are derived according to spherical analytical theory and the principle of coordinate transformation.Secondly,the structural constraint equations are constructed by applying cosine formula of spherical triangles to the top platform of the mechanism.Thirdly,the constraint equations are solved by using Bezout’ s elimination method for forward analysis and Sylvester’ s resultant elimination method for inverse kinematics respectively.By the aid of computer symbolic systems,Mathematica and Maple,symbolic closed-form solution of forward and inverse displacement analysis of spherical Stephenson-III six-bar mechanism are obtained.Finally,numerical examples of forward and inverse analysis are presented to illustrate the proposed approach.The results indicate that the constraint equations established with the proposed method are much simpler than those reported by previous literature,and can be readily eliminated and solved. 展开更多
关键词 spherical Stephenson-III six-bar mechanisms kinematic analysis spherical analytical theory Bezout' s elimination method Sylvester' s elimination method
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Balancing Chemical Equations by Systems of Linear Equations 被引量:1
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作者 Ihsanullah Hamid 《Applied Mathematics》 2019年第7期521-526,共6页
In this paper, a formal and systematic method for balancing chemical reaction equations was presented. The results satisfy the law of conservation of matter, and confirm that there is no contradiction to the existing ... In this paper, a formal and systematic method for balancing chemical reaction equations was presented. The results satisfy the law of conservation of matter, and confirm that there is no contradiction to the existing way(s) of balancing chemical equations. A chemical reaction which possesses atoms with fractional oxidation numbers that have unique coefficients was studied. In this paper, the chemical equations were balanced by representing the chemical equation into systems of linear equations. Particularly, the Gauss elimination method was used to solve the mathematical problem with this method, it was possible to handle any chemical reaction with given reactants and products. 展开更多
关键词 CHEMICAL REACTION Linear EQUATIONS Balancing CHEMICAL EQUATIONS MATRIX GAUSS elimination method
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Applications of interval arithmetic in solving polynomial equations by Wu's elimination method
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作者 CHEN Falai YANG Wu 《Science China Mathematics》 SCIE 2005年第9期1260-1273,共14页
Wu's elimination method is an important method for solving multivariate polynomial equations. In this paper, we apply interval arithmetic to Wu's method and convert the problem of solving polynomial equations ... Wu's elimination method is an important method for solving multivariate polynomial equations. In this paper, we apply interval arithmetic to Wu's method and convert the problem of solving polynomial equations into that of solving interval polynomial equations. Parallel results such as zero-decomposition theorem are obtained for interval polynomial equations. The advantages of the new approach are two-folds: First, the problem of the numerical instability arisen from floating-point arithmetic is largely overcome. Second,the low efficiency of the algorithm caused by large intermediate coefficients introduced by exact compaction is dramatically improved. Some examples are provided to illustrate the effectiveness of the proposed algorithm. 展开更多
关键词 MATHEMATICAL mechanization wu's method POLYNOMIAL equation INTERVAL arithmetic.
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An Algorithm for Finding All Isolated Zeros of Polynomial Systems
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作者 刘卓军 《Chinese Quarterly Journal of Mathematics》 CSCD 1992年第4期26-34,共9页
Finding all zeros of polynomial systems is very interesting and it is also useul for many applied science problems.In this paper,based on Wu's method,we give an algorithm to find all isolated zeros of polynomial s... Finding all zeros of polynomial systems is very interesting and it is also useul for many applied science problems.In this paper,based on Wu's method,we give an algorithm to find all isolated zeros of polynomial systems (or polynomial equations).By solving Lorenz equations,it is shown that our algo-rithm is efficient and powerful. 展开更多
关键词 wu's method polynomial system zeros of polynomial system
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Space Discretization of Time-Fractional Telegraph Equation with Mamadu-Njoseh Basis Functions
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作者 Ebimene James Mamadu Ignatius Nkonyeasua Njoseh Henrietta Ify Ojarikre 《Applied Mathematics》 2022年第9期760-773,共14页
In this paper, we examine the space discretization of time fractional telegraph equation (TFTE) with Mamadu-Njoseh orthogonal basis functions. For ease and convenience, we deal with the fractional derivative by first ... In this paper, we examine the space discretization of time fractional telegraph equation (TFTE) with Mamadu-Njoseh orthogonal basis functions. For ease and convenience, we deal with the fractional derivative by first converting from Caputo’s type to Riemann-Liouville’s type. The proposed method was constrained to precise error analysis to establish the accuracy of the method. Numerical experimentation was implemented with the aid of MAPLE 18 to show convergence of the method as compared with the analytic solution. 展开更多
关键词 Finite Difference method Mamadu-Njoseh Polynomials Telegraph Equation Gaussian elimination method Quadrature Formula Sobolev Space
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Algebraic Cryptanalysis of GOST Encryption Algorithm
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作者 Ludmila Babenko Ekaterina Maro 《Journal of Computer and Communications》 2014年第4期10-17,共8页
This paper observes approaches to algebraic analysis of GOST 28147-89 encryption algorithm (also known as simply GOST), which is the basis of most secure information systems in Russia. The general idea of algebraic an... This paper observes approaches to algebraic analysis of GOST 28147-89 encryption algorithm (also known as simply GOST), which is the basis of most secure information systems in Russia. The general idea of algebraic analysis is based on the representation of initial encryption algorithm as a system of multivariate quadratic equations, which define relations between a secret key and a cipher text. Extended linearization method is evaluated as a method for solving the nonlinear sys- tem of equations. 展开更多
关键词 ENCRYPTION Algorithm GOST GOST S-BOX Systems of MULTIVARIATE Quadratic Equations ALGEBRAIC CRYPTANALYSIS Extended LINEARIZATION method Gaussian elimination
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Solution Building for Arbitrary System of Linear Inequalities in an Explicit Form
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作者 Demetrius V. Shapot Alexander M. Lukatskii 《American Journal of Computational Mathematics》 2012年第1期1-11,共11页
The known Fourier-Chernikov algorithm of linear inequality system convolution is complemented with an original procedure of all dependent (redundant) inequalities deletion. The concept of “almost dependent” inequali... The known Fourier-Chernikov algorithm of linear inequality system convolution is complemented with an original procedure of all dependent (redundant) inequalities deletion. The concept of “almost dependent” inequalities is defined and an algorithm for further reducing the system by deletion of these is considered. The concluding algorithm makes it possible to hold actual-time convolution of a general inequality system containing up to 50 variables with the rigorous method of dependent inequalities deletion and up to 100 variables with the approximate method of one. The main application of such an approach consists in solving linear inequality system in an explicit form. These results are illustrated with a series of computer experiments. 展开更多
关键词 Linear INEQUALITIES Convolution Variable elimination Orthogonal Projection method Fourier Algorithm Chernikov Rules DEPENDENT INEQUALITIES REDUNDANT INEQUALITIES ALMOST DEPENDENT INEQUALITIES Matrix CLEANUP COARSENING
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The Application of Sylvester Matrix to Analyze in Robotic Position
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作者 ZENG Ke-ke 《International Journal of Plant Engineering and Management》 2017年第1期21-26,共6页
The elimination method is a general method to solve equations. The resultant method is an important tool in elimination theory. In the analysis of robot pose, equations are solved according to its graph. Resultants ca... The elimination method is a general method to solve equations. The resultant method is an important tool in elimination theory. In the analysis of robot pose, equations are solved according to its graph. Resultants can simplify to solve system equation. 展开更多
关键词 elimination method EQUATIONS robot resultant method
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ON A NEW ALGORITHM OF CONSTRUCTING SOLITARY WAVE SOLUTIONS FOR SYSTEMS OF NONLINEAR EVOLU-TION EQUATIONS IN MATHEMATICAL PHYSICS
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作者 闫振亚 张鸿庆 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2000年第4期383-388,共6页
According to the improved sine-cosine method and Wu-elimination method, a new algorithm to construct solitary wave solutions for systems of nonlinear evolution equations is put forward. The algorithm has some conclusi... According to the improved sine-cosine method and Wu-elimination method, a new algorithm to construct solitary wave solutions for systems of nonlinear evolution equations is put forward. The algorithm has some conclusions which are better than what the hyperbolic function method known does and simpler in use. With the aid of MATHEMATICA, the algorithm can be carried out in computer. 展开更多
关键词 system of nonlinear evolution equations sine-cosine method Wu-elimination method solitary wave solution
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APPLICATION OF MECHANIZED MATHEMATICS TO ROTOR DYNAMICS
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作者 胡超 王岩 +1 位作者 王立国 黄文虎 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2002年第9期1045-1053,共9页
Based on the mechanized mathematics and WU Wen-tsun elimination method, using oil film forces of short-bearing model and Muszynska's dynamic model, the dynamical behavior of rotor-beating system and its stability ... Based on the mechanized mathematics and WU Wen-tsun elimination method, using oil film forces of short-bearing model and Muszynska's dynamic model, the dynamical behavior of rotor-beating system and its stability of motion are investigated. As example, the concept of Wu characteristic set and Maple software, whirl parameters of short-bearing model, which is usually solved by the numerical method, are analyzed. At the same time, stability of zero solution of Jeftcott rotor whirl equation and stability of self-excited vibration are studied. The conditions of stable motion are obtained by using theory of nonlinear vibration. 展开更多
关键词 Wu-elimination method characteristic set stability of motion rotor-bearing system whirl
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