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Bifurcation analysis and exact traveling wave solutions for (2+1)-dimensional generalized modified dispersive water wave equation 被引量:3
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作者 Ming Song Beidan Wang Jun Cao 《Chinese Physics B》 SCIE EI CAS CSCD 2020年第10期148-153,共6页
We investigate (2+1)-dimensional generalized modified dispersive water wave (GMDWW) equation by utilizing the bifurcation theory of dynamical systems. We give the phase portraits and bifurcation analysis of the plane ... We investigate (2+1)-dimensional generalized modified dispersive water wave (GMDWW) equation by utilizing the bifurcation theory of dynamical systems. We give the phase portraits and bifurcation analysis of the plane system corresponding to the GMDWW equation. By using the special orbits in the phase portraits, we analyze the existence of the traveling wave solutions. When some parameter takes special values, we obtain abundant exact kink wave solutions, singular wave solutions, periodic wave solutions, periodic singular wave solutions, and solitary wave solutions for the GMDWW equation. 展开更多
关键词 bifurcation theory generalized modified dispersive water wave equation traveling wave solution
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Construction of Recursion Formulas for Lax Pairs of (2+1)-Dimensional Equation: Modified Generalized Dispersive Long Wave Equation
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作者 TIANYong-Bo CHENGYi SHAONan 《Communications in Theoretical Physics》 SCIE CAS CSCD 2004年第6期807-812,共6页
In this article, we study the Lax pairs of -dimensional equation: the modified generalized dispersive long wave (MGDLW) equation. Based on the well-known binary Darboux transformation, we dig out the recursion formula... In this article, we study the Lax pairs of -dimensional equation: the modified generalized dispersive long wave (MGDLW) equation. Based on the well-known binary Darboux transformation, we dig out the recursion formulas of the first part of the Lax pairs. Then by further discussion and doing some revisional work, we make the recursion formulas fit for the second part of Lax pairs. At last, some solutions to the MGDLW equation are worked out by using the recursion formula. 展开更多
关键词 Lax pairs modified generalized dispersive long wave equation recursion formula SOLUTIONS
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Modified Generalized Degree Distance of Some Graph Operations
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作者 Shengmei Lv 《Advances in Pure Mathematics》 2018年第6期548-558,共11页
The modified generality degree distance, is defined as: ,?which is a modification of the generality degree distance. In this paper, we give some computing formulas of the modified generality degree distance of some gr... The modified generality degree distance, is defined as: ,?which is a modification of the generality degree distance. In this paper, we give some computing formulas of the modified generality degree distance of some graph operations, such as, composition, join, etc. 展开更多
关键词 DEGREE DISTANCE modified generalized DEGREE DISTANCE GRAPH Operations
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Modified Maximum Likelihood Estimation in Autoregressive Processes with Generalized Exponential Innovations
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作者 Bernardo Lagos-álvarez Guillermo Ferreira Emilio Porcu 《Open Journal of Statistics》 2014年第8期620-629,共10页
We consider a time series following a simple linear regression with first-order autoregressive errors belonging to the class of heavy-tailed distributions. The proposed model provides a useful generalization of the sy... We consider a time series following a simple linear regression with first-order autoregressive errors belonging to the class of heavy-tailed distributions. The proposed model provides a useful generalization of the symmetrical linear regression models with independent error, since the error distribution covers both correlated innovations following a Generalized Exponential distribution. Furthermore, we derive the modified maximum likelihood (MML) estimators as an efficient alternative for estimating model parameters. Finally, we investigate the asymptotic properties of the proposed estimators. Our findings are also illustrated through a simulation study. 展开更多
关键词 AUTOREGRESSIVE Time Series Model MAXIMUM LIKELIHOOD modified MAXIMUM LIKELIHOOD Least SQUARES generalized EXPONENTIAL
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Exact Solutions for the Generalized KdV Equation: Modified Homogeneous Balance Method
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作者 WANG Xiu-mei ZHU Yue-feng 《Chinese Quarterly Journal of Mathematics》 CSCD 北大核心 2008年第2期260-269,共10页
In this paper, we present a solution methodology to obtain exact solutions of some nonlinear evolution equation by modifying the homogeneous balance method. Based on the modified homogeneous balance method, several ki... In this paper, we present a solution methodology to obtain exact solutions of some nonlinear evolution equation by modifying the homogeneous balance method. Based on the modified homogeneous balance method, several kinds of exact(new) solutions of the generalized KdV equation are obtained. 展开更多
关键词 generalized KdV equation modified homogeneous balance method exact solutions
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Generalized Kumaraswamy Generalized Power Gompertz Distribution: Statistical Properties, Application, and Validation Using a Modified Chi-Squared Goodness of Fit Test
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作者 Obubu Maxwell Ibeakuzie Precious Onyedikachi +2 位作者 Khaoula Aidi Chijioke Igwe Akpa Nacira Seddik-Ameur 《Applied Mathematics》 2022年第3期243-262,共20页
A new six-parameter continuous distribution called the Generalized Kumaraswamy Generalized Power Gompertz (GKGPG) distribution is proposed in this study, a graphical illustration of the probability density function an... A new six-parameter continuous distribution called the Generalized Kumaraswamy Generalized Power Gompertz (GKGPG) distribution is proposed in this study, a graphical illustration of the probability density function and cumulative distribution function is presented. The statistical features of the Generalized Kumaraswamy Generalized Power Gompertz distribution are systematically derived and adequately studied. The estimation of the model parameters in the absence of censoring and under-right censoring is performed using the method of maximum likelihood. The test statistic for right-censored data, criteria test for GKGPG distribution, estimated matrix &#372;, &#264;, and &#284;, criteria test Y<sup>2</sup>n</sub>, alongside the quadratic form of the test statistic is derived. Mean simulated values of maximum likelihood estimates and their corresponding square mean errors are presented and confirmed to agree closely with the true parameter values. Simulated levels of significance for Y<sup>2</sup>n</sub> (γ) test for the GKGPG model against their theoretical values were recorded. We conclude that the null hypothesis for which simulated samples are fitted by GKGPG distribution is widely validated for the different levels of significance considered. From the summary of the results of the strength of a specific type of braided cord dataset on the GKGPG model, it is observed that the proposed GKGPG model fits the data set for a significance level ε = 0.05. 展开更多
关键词 Power Gompertz generalized Kumaraswamy-G modified Chi-Squared the Goodness of Fit CENSORING
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Generalized Wronskian Solutions to Modified Korteweg-de Vries Equation via Its Bcklund Transformation
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作者 XUAN Qi-Fei ZHANG Da-Jun 《Communications in Theoretical Physics》 SCIE CAS CSCD 2008年第7期13-16,共4页
In the paper we discuss the Wronskian solutions of modified Korteweg-de Vries equation (mKdV) via the Backlund transformation (BT) and a generalized Wronskian condition is given, which allows us to substitute an a... In the paper we discuss the Wronskian solutions of modified Korteweg-de Vries equation (mKdV) via the Backlund transformation (BT) and a generalized Wronskian condition is given, which allows us to substitute an arbitrary coefficient matrix in the GN (t) for the original diagonal one. 展开更多
关键词 the modified Korteweg-de Vries equation (mKdV) generalized Wronskian solutions bilinear form Backlund transformation (BT)
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Symmetry and Exact Solutions of (2+1)-Dimensional Generalized Sasa-Satsuma Equation via a Modified Direct Method
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作者 LU Chang-Cheng CHEN Yong 《Communications in Theoretical Physics》 SCIE CAS CSCD 2009年第6期973-978,共6页
In this paper, first, we employ classic Lie symmetry groups approach to obtain the Lie symmetry groupsof the well-known (2+1)-dimensional Generalized Sasa-Satsuma (GSS) equation. Second, based on a modified directmeth... In this paper, first, we employ classic Lie symmetry groups approach to obtain the Lie symmetry groupsof the well-known (2+1)-dimensional Generalized Sasa-Satsuma (GSS) equation. Second, based on a modified directmethod proposed by Lou [J. Phys. A: Math. Gen. 38 (2005) L129], more general symmetry groups are obtained andthe relationship between the new solution and known solution is set up. At the same time, the Lie symmetry groupsobtained are only special cases of the more general symmetry groups. At last, some exact solutions of GSS equationsare constructed by the relationship obtained in the paper between the new solution and known solution. 展开更多
关键词 classic Lie symmetry groups approach modified CK's direct method generalized Sasa-Satsuma equation
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Relativistic Treatment of Massive Klein-Gordon Particle by Modified Generalized Hulthen Potential
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作者 Akaninyene D. Antia Imeh E. Essien Joseph G. Atat 《Journal of Mathematics and System Science》 2017年第2期73-78,共6页
Approximate bound state solutions of spinless particles with a special case of equal scalar and vector modified generalized Hulthen potential has been obtained under the massive Klein-Gordon equation. The energy eigen... Approximate bound state solutions of spinless particles with a special case of equal scalar and vector modified generalized Hulthen potential has been obtained under the massive Klein-Gordon equation. The energy eigenvalues and the corresponding wave functions expressed in terms of a Jacobi polynomial are also obtained using the parametric generalization of the Nikiforov-Uvarov (NU) method. Under limiting cases our result are in agreement with the existing literature. Our results could be used to study the interactions and binding energies of the central potential for diatomic molecules in the relativistic framework which have many applications in physics and some others related disciplines. 展开更多
关键词 Massive Klein-Gordon equation modified generalized Hulthen potential eigenvalues wave function Nikiforov-Uvarovmethod and potential barrier.
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Enhancing the resolution of seismic data based on the generalized S-transform 被引量:3
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作者 Tian Jianhua Song Wei Yang Feizhou 《Petroleum Science》 SCIE CAS CSCD 2009年第2期153-157,共5页
In this paper, we analyze the seismic signal in the time-frequency domain using the generalized S-transform combined with spectrum modeling. Without assuming that the reflection coefficients are random white noise as ... In this paper, we analyze the seismic signal in the time-frequency domain using the generalized S-transform combined with spectrum modeling. Without assuming that the reflection coefficients are random white noise as in the conventional resolution-enhanced techniques, the wavelet which changes with time and frequency was simulated and eliminated. After using the inverse S-transform for the processed instantaneous spectrum, the signal in the time domain was obtained again with a more balanced spectrum and broader frequency band. The quality of seismic data was improved without additional noise. 展开更多
关键词 Time-frequency domain generalized s-transform spectrum modeling instantaneous spectrum balanced spectrum
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A Protection Method of VSC-HVDC Cables Based on Generalized S-Transform 被引量:2
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作者 Weishi Man Xiaoman Bei Zhiyu Zhang 《Energy and Power Engineering》 2021年第4期1-10,共10页
<div style="text-align:justify;"> Generalized S-transform is a time-frequency analysis method which has higher resolution than S-transform. It can precisely extract the time-amplitude characteristics o... <div style="text-align:justify;"> Generalized S-transform is a time-frequency analysis method which has higher resolution than S-transform. It can precisely extract the time-amplitude characteristics of different frequency components in the signal. In this paper, a novel protection method for VSC-HVDC (Voltage source converter based high voltage DC) based on Generalized S-transform is proposed. Firstly, extracting frequency component of fault current by Generalized S-transform and using mutation point of high frequency to determine the fault time. Secondly, using the zero-frequency component of fault current to eliminate disturbances. Finally, the polarity of sudden change currents in the two terminals is employed to discriminate the internal and external faults. Simulations in PSCAD/EMTDC and MATLAB show that the proposed method can distinguish faults accurately and effectively. </div> 展开更多
关键词 generalized s-transform VSC-HVDC Phase-Mode Transformation DC Cable Protection
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Detection and correction of level echo based on generalized S-transform and singular value decomposition 被引量:1
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作者 ZHU Tianliang WANG Xiaopeng WANG Qi 《Journal of Measurement Science and Instrumentation》 CAS CSCD 2021年第4期442-448,共7页
The echo of the material level is non-stationary and contains many singularities.The echo contains false echoes and noise,which affects the detection of the material level signals,resulting in low accuracy of material... The echo of the material level is non-stationary and contains many singularities.The echo contains false echoes and noise,which affects the detection of the material level signals,resulting in low accuracy of material level measurement.A new method for detecting and correcting the material level signal is proposed,which is based on the generalized S-transform and singular value decomposition(GST-SVD).In this project,the change of material level is regarded as the low speed moving target.First,the generalized S-transform is performed on the echo signals.During the transformation process,the variation trend of window of the generalized S-transform is adjusted according to the frequency distribution characteristics of the material level echo signal,achieving the purpose of detecting the signal.Secondly,the SVD is used to reconstruct the time-frequency coefficient matrix.At last,the reconstructed time-frequency matrix performs an inverse transform.The experimental results show that the method can accurately detect the material level echo signal,and it can reserve the detailed characteristics of the signal while suppressing the noise,and reduce the false echo interference.Compared with other methods,the material level measurement error does not exceed 4.01%,and the material level measurement accuracy can reach 0.40%F.S. 展开更多
关键词 echo signal false echo generalized s-transform singular value decomposition(SVD) level measurement
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Identification of transgene insertions in two genetically modified soybeans using high throughput next generation sequencing
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作者 Shouwei Zhang Shi Sun +6 位作者 Jing Sun Xiujie Liu Wensheng Hou Tingting Wu Cunxiang Wu Tianfu Han Bingjun Jiang 《Oil Crop Science》 2018年第2期92-98,共7页
Genetically modified(GM) organisms are widely adopted. However, their safety assessments and control are still of special concern to the public. Identifying and localizing transgene insertion is an essentially prerequ... Genetically modified(GM) organisms are widely adopted. However, their safety assessments and control are still of special concern to the public. Identifying and localizing transgene insertion is an essentially prerequisite step. In this study, 2 independent transgene soybean lines were selected(LB4-AtDCGS-1-20-5-2 and CGS-ZG11) as typical cases. Both lines contained expression cassette of At-DCGS that encoding a feedback-insensitive cystathionine gamma-synthase to produce higher level methionine(Met). LB4-AtDCGS-1-20-5-2 was whole genome sequenced with one paired-end 500 bp library and two mate-paired 1 kb and 2 kb libraries using Illumina HiSeq sequencing platform. CGS-ZG11 was sequenced with only one paired-end 500 bp library. Both genomes were assembled,and 2 scaffold sequences(1 for each line) were screened out by aligning with transgene.Then the transgene insertion and its flanking regions in soybean genome were further identified and confirmed by PCR cloning and Sanger sequencing. Results showed that these 2 transgene lines had single copy of inserted transgene. Their transgene insertion contents were identified, which facilitates further safety assessment. These results indicated that genome assembly using high throughput sequencing is a powerful tool for identifying transgene insertions, even with limited knowledge. 展开更多
关键词 genetically modified soybean high METHIONINE TRANSGENE INSERTION identification next generation sequencing
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A Modified Paving Approach and Automatic Mesh Grading Method to Quadrilateral Mesh Generation 被引量:1
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作者 Mei Zhongyi Fan Yuqing Hu Shiguang(School of Mechanical Engineering and Automation,Beijing University of Aeronautics and Astronautics, Beijing 100083, P.R.China) 《Computer Aided Drafting,Design and Manufacturing》 1999年第1期39-51,共13页
A modified paving technique for automatic generation of all-quadrilateral mesh fromarbitrary 2-D geometry is presented. The generated mesh elementS are nearly square andperpendicular to boundaries. Aner the nodes and... A modified paving technique for automatic generation of all-quadrilateral mesh fromarbitrary 2-D geometry is presented. The generated mesh elementS are nearly square andperpendicular to boundaries. Aner the nodes and elementS formation is completed. a fully automaticgrading method is applied to increase the accuracy and reliability of engineering analysis. In thispaper, we mainly describe the theory of mathematical algorithm and present some examples ofautomatically generated mesh. 展开更多
关键词 mesh generation quadrilateral element modified paving technique mesh grading
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Application of SAGE algorithm in PET image reconstruction using modified ordered subsets 被引量:1
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作者 朱宏擎 舒华忠 +1 位作者 周健 罗立民 《Journal of Southeast University(English Edition)》 EI CAS 2005年第3期319-323,共5页
A new method that uses a modified ordered subsets (MOS) algorithm to improve the convergence rate of space-alternating generalized expectation-maximization (SAGE) algorithm for positron emission tomography (PET)... A new method that uses a modified ordered subsets (MOS) algorithm to improve the convergence rate of space-alternating generalized expectation-maximization (SAGE) algorithm for positron emission tomography (PET) image reconstruction is proposed.In the MOS-SAGE algorithm,the number of projections and the access order of the subsets are modified in order to improve the quality of the reconstructed images and accelerate the convergence speed.The number of projections in a subset increases as follows:2,4,8,16,32 and 64.This sequence means that the high frequency component is recovered first and the low frequency component is recovered in the succeeding iteration steps.In addition,the neighboring subsets are separated as much as possible so that the correlation of projections can be decreased and the convergences can be speeded up.The application of the proposed method to simulated and real images shows that the MOS-SAGE algorithm has better performance than the SAGE algorithm and the OSEM algorithm in convergence and image quality. 展开更多
关键词 positron emission tomography space-alternating generalized expectation-maximization: imagereconstruction modified ordered subsets
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Modified Improved Boussinesq方程的精确解
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作者 姬天富 《连云港职业技术学院学报》 2009年第2期21-23,共3页
借助Mathematics4.0软件、改进的广义幂指函数法研究了Modified Improved Boussinesq方程,得到了方程的精确解,这种方法也适合研究其它的非线性发展方程.
关键词 改进的广义幂指函数法 modified IMPROVED BOUSSINESQ方程 精确解
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Some new exact solutions of Jacobian elliptic function about the generalized Boussinesq equation and Boussinesq-Burgers equation 被引量:9
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作者 张亮 张立凤 李崇银 《Chinese Physics B》 SCIE EI CAS CSCD 2008年第2期403-410,共8页
By using the modified mapping method, we find some new exact solutions of the generalized Boussinesq equation and the Boussinesq-Burgers equation. The solutions obtained in this paper include Jacobian elliptic functio... By using the modified mapping method, we find some new exact solutions of the generalized Boussinesq equation and the Boussinesq-Burgers equation. The solutions obtained in this paper include Jacobian elliptic function solutions, combined Jacobian elliptic function solutions, soliton solutions, triangular function solutions. 展开更多
关键词 generalized Boussinesq equation Boussinesq-Burgers equation Jacobian elliptic function modified mapping method
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Diagnostic Analyses of the Modified Convective Vorticity Vector in Non-uniformly Saturated Moist Flow 被引量:5
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作者 YANG Shuai WANG Dong-Hai 《Atmospheric and Oceanic Science Letters》 2009年第3期142-147,共6页
Because the real atmosphere is non-uniformly saturated, the generalized potential temperature is introduced. The convective vorticity vector, which can depict the occurrence and development of mesoscale deep convectiv... Because the real atmosphere is non-uniformly saturated, the generalized potential temperature is introduced. The convective vorticity vector, which can depict the occurrence and development of mesoscale deep convective systems, is modified and re-derived in a nonuniformly saturated moist atmosphere (C*). Then, a case study is performed for a frontal rainfall event which occurred near the middle and lower reaches of the Yangtze River in China. The diagnostic results of C* show that, in the lower troposphere, the vertical component of C* (Cz*) can diagnose developments and movements of precipitation and convection better than those of Cm (Cmz, in saturated moist flow) and C (Cz, in dry flow). Cz* is a good predictor for precipitation analyses as well. 展开更多
关键词 non-uniform saturation generalized potentialtemperature modified convective vorticity vector
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Bidirectional Partial Generalized Synchronization in Chaotic and Hyperchaotic Systems via a New Scheme 被引量:2
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作者 WANG Qi 《Communications in Theoretical Physics》 SCIE CAS CSCD 2006年第6期1049-1056,共8页
In this paper, a bidirectional partial generalized (lag, complete, and anticipated) synchronization of a class of continuous-time systems is defined. Then based on the active control idea, a new systematic and concr... In this paper, a bidirectional partial generalized (lag, complete, and anticipated) synchronization of a class of continuous-time systems is defined. Then based on the active control idea, a new systematic and concrete scheme is developed to achieve bidirectional partial generalized (lag, complete, and anticipated) synchronization between two chaotic systems or between chaotic and hyperchaotic systems. With the help of symbolic-numerical computation, we choose the modified Chua system, Lorenz system, and the hyperchaotic Tamasevicius Namajunas-Cenys system to illustrate the proposed scheme. Numerical simulations are used to verify the effectiveness of the proposed scheme. It is interesting that partial chaos synchronization not only can take place between two chaotic systems, but also can take place between chaotic and hyperchaotic systems. The proposed scheme can also be extended to research bidirectional partial generalized (lag, complete, and anticipated) synchronization between other dynamical systems. 展开更多
关键词 bidirectional partial generalized (lag COMPLETE and anticipated) synchronization modified Chua system Lorenz system hyperchaotic Tamasevicius-Namajunas-Cenys system numerical simulation
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Symmetry Groups and New Exact Solutions to (2+1)-Dimensional Variable Coefficient Canonical Generalized KP Equation 被引量:7
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作者 ZHANG Li-Hua LIU Xi-Qiang BAI Cheng-Lin 《Communications in Theoretical Physics》 SCIE CAS CSCD 2007年第3X期405-410,共6页
In this paper, the modified CK's direct method to find symmetry groups of nonlinear partial differential equation is extended to (2+1)-dimensional variable coeffficient canonical generalized KP (VCCGKP) equation... In this paper, the modified CK's direct method to find symmetry groups of nonlinear partial differential equation is extended to (2+1)-dimensional variable coeffficient canonical generalized KP (VCCGKP) equation. As a result, symmetry groups, Lie point symmetry group and Lie symmetry for the VCCGKP equation are obtained. In fact, the Lie point symmetry group coincides with that obtained by the standard Lie group approach. Applying the given Lie symmetry, we obtain five types of similarity reductions and a lot of new exact solutions, including hyperbolic function solutions, triangular periodic solutions, Jacobi elliptic function solutions and rational solutions, for the VCCGKP equation. 展开更多
关键词 (2+1)-dimensional variable coefficient canonical generalized KP (VCCGKP) equation modified CK's'direct method symmetry groups Lie symmetry similarity reductions new exact solutions
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