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A New Generalization of Extended Tanh—Function Method for Solving Nonlinear Evolution Equations 被引量:15
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作者 ZHENGXue-Dong CHENYong LIBiao ZHANGHong-Qing 《Communications in Theoretical Physics》 SCIE CAS CSCD 2003年第6期647-652,共6页
Making use of a new generalized ansatze and a proper transformation, we generalized the extended tanh-function method. Applying the generalized method with the aid of Maple, we consider some nonlinear evolution equati... Making use of a new generalized ansatze and a proper transformation, we generalized the extended tanh-function method. Applying the generalized method with the aid of Maple, we consider some nonlinear evolution equations.As a result, we can successfully recover the previously known solitary wave solutions that had been found by the extendedtanh-function method and other more sophisticated methods. More importantly, for some equations, we also obtain othernew and more general solutions at the same time. The results include kink-profile solitary-wave solutions, bell-profilesolitary-wave solutions, periodic wave solutions, rational solutions, singular solutions and new formal solutions. 展开更多
关键词 非线性演化方程 精确解 双曲正切函数 RICCATI方程 非线性偏微分方程 符号计算
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New Multiple Soliton-like Solutions to (3+1)-Dimensional Burgers Equation with Variable Coefficients 被引量:16
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作者 CHENHuai-Tang ZHANGHong-Qing 《Communications in Theoretical Physics》 SCIE CAS CSCD 2004年第4X期497-500,共4页
A new generalized tanh function method is used for constructing exact travelling wave solutions of nonlinear partial differential equations in a unified way. The main idea of this method is to take full advantage of t... A new generalized tanh function method is used for constructing exact travelling wave solutions of nonlinear partial differential equations in a unified way. The main idea of this method is to take full advantage of the Riccati equation, which has more new solutions. More new multiple soliton-like solutions are obtained for the (3+ 1 )-dimensional Burgers equation with variable coefficients. 展开更多
关键词 行波解 类孤立子解 RICCATI方程 非线性偏微分方程 变量系数 双曲正切函数 传输波解
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Symbolic Computation and Construction of Soliton-Like Solutions to the(2+l)-Dimensional Breaking Soliton Equation 被引量:12
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作者 CHENYong LIBiao ZHANGHong-Qing 《Communications in Theoretical Physics》 SCIE CAS CSCD 2003年第2X期137-142,共6页
Based on the computerized symbolic system Mapte, a new generalized expansion method of Riccati equation for constructing non-travelling wave and coefficient functions' soliton-like solutions is presented by a new ... Based on the computerized symbolic system Mapte, a new generalized expansion method of Riccati equation for constructing non-travelling wave and coefficient functions' soliton-like solutions is presented by a new general ansatz. Making use of the method, we consider the (2+1)-dimensional breaking soliton equation, ut + buxxy + 4buvx+4buxv = O,uv=vx, and obtain rich new families of the exact solutions of the breaking sofiton equation, including then on-traveilin~ wave and constant function sofiton-like solutions, singular soliton-like solutions, and triangular function solutions. 展开更多
关键词 符号计算 RICCATI方程 广义扩展方法 (2+l)维断裂孤子方程 类孤波解 建筑工程
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Some New Exact Solutions to the Dispersive Long-Wave Equation in(2+1)-Dimensional Spaces 被引量:17
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作者 LIDe-Sheng ZHANGHong-Qing 《Communications in Theoretical Physics》 SCIE CAS CSCD 2003年第2X期143-146,共4页
In this paper, by using a further extended tanh method- and symbolic computation system, some new soliton-like and period form solutions of the dispersive long-wave equation in (2+l )-dimensional spaces are obtained.
关键词 (2+l)维空间 符号计算系统 类孤波解 扩展双曲正切方法 周期解 孤波
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The soliton-like solutions to the (2+1)-dimensional modified dispersive water-wave system 被引量:16
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作者 李德生 张鸿庆 《Chinese Physics B》 SCIE EI CAS CSCD 2004年第7期984-987,共4页
By a simple transformation, we reduce the (2+1)-dimensional modified dispersive water-wave system to a simple nonlinear partial differential equation. In order to solve this equation by generalized tanh-function metho... By a simple transformation, we reduce the (2+1)-dimensional modified dispersive water-wave system to a simple nonlinear partial differential equation. In order to solve this equation by generalized tanh-function method, we only need to solve a simple system of first-order ordinary differential equations, and by doing so we can obtain many new soliton-like solutions which include the solutions obtained by using the conventional tanh-function method. 展开更多
关键词 类孤立解 三维修正扩散水波系统 广义双曲正切函数理论 流体力学
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New explicit exact solutions for a generalized Hirota—Satsuma coupled KdV system and a coupled MKdV equation 被引量:12
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作者 陈勇 闫振亚 《Chinese Physics B》 SCIE EI CAS CSCD 2003年第1期1-10,共10页
In this paper,we make use of a new generalized ansatz in the homogeneous balance method,the well-known Riccati equation and the symbolic computation to study a generalized hirota-Satsuma coupled KdsV system and a coup... In this paper,we make use of a new generalized ansatz in the homogeneous balance method,the well-known Riccati equation and the symbolic computation to study a generalized hirota-Satsuma coupled KdsV system and a coupled MKdv equation,respectively,As a result,numerous explicit exact solutions,comprising new solitary wave solutions,periodic wave solutions and the combined formal solitary wave solutions and periodic wave solutions,are obtained. 展开更多
关键词 非线性偏微分程 KDV系统 MKDV方程 严格解
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New Exact Travelling Wave Solutions for Generalized Zakharov-Kuzentsov EquationsUsing General Projective Riccati Equation Method 被引量:14
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作者 CHENYong LIBiao 《Communications in Theoretical Physics》 SCIE CAS CSCD 2004年第1期1-6,共6页
Applying the generalized method, which is a direct and unified algebraic method for constructing multipletravelling wave solutions of nonlinear partial differential equations (PDEs), and implementing in a computer alg... Applying the generalized method, which is a direct and unified algebraic method for constructing multipletravelling wave solutions of nonlinear partial differential equations (PDEs), and implementing in a computer algebraicsystem, we consider the generalized Zakharov-Kuzentsov equation with nonlinear terms of any order. As a result, wecan not only successfully recover the previously known travelling wave solutions found by existing various tanh methodsand other sophisticated methods, but also obtain some new formal solutions. The solutions obtained include kink-shapedsolitons, bell-shaped solitons, singular solitons, and periodic solutions. 展开更多
关键词 行波解 Zakharov-Kuzentsov方程 精确解 Riccati投影 非线性偏微分方程 周期解 计算物理学
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Positive Periodic Solutions of Nonlinear Second Order Ordinary Differential Equations 被引量:7
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作者 PENGShi-guo 《应用数学》 CSCD 北大核心 2004年第2期234-238,共5页
This paper discusses the problem of positive periodic solutions for a class of nonlinearsecond order ordinary differential equations. By utilizing a fixed point theorem on cone, some exist-ence and multiplicity result... This paper discusses the problem of positive periodic solutions for a class of nonlinearsecond order ordinary differential equations. By utilizing a fixed point theorem on cone, some exist-ence and multiplicity results of positive periodic solutions are derived. Our results improve theoremsin the literature. 展开更多
关键词 非线性二阶常微分方程 正周期解 存在性 多重性 Banach空间锥 不动点定理
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Generation and synchronization of N-scroll chaotic and hyperchaotic attractors in fourth-order systems 被引量:12
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作者 禹思敏 马在光 +7 位作者 丘水生 彭世国 林清华 禹思敏 马在光 丘水生 彭世国 林清华 《Chinese Physics B》 SCIE EI CAS CSCD 2004年第3期317-328,共12页
Based on our previous works and Lyapunov stability theory, this paper studies the generation and synchronization of N-scroll chaotic and hyperchaotic attractors in fourth-order systems. A fourth-order circuit, by intr... Based on our previous works and Lyapunov stability theory, this paper studies the generation and synchronization of N-scroll chaotic and hyperchaotic attractors in fourth-order systems. A fourth-order circuit, by introducing additional breakpoints in the modified Chua oscillator, is implemented for the study of generation and synchronization of N-scroll chaotic attractors.This confirms the consistency of theoretical calculation, numerical simulation and circuit experiment.Furthermore,we give a refined and extended study of generating and synchronizing N-scroll hyperchaotic attractors in the fourth-order MCK system and report the new theoretical result, which is verified by computer simulations. 展开更多
关键词 第四阶系统 N形卷动混沌吸引器 N形卷动超混沌吸引器 四阶循环 同步 混沌通信
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Stochastic resonance in an asymmetric bistable system driven by multiplicative and additive noise 被引量:6
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作者 徐伟 靳艳飞 +1 位作者 李伟 马少娟 《Chinese Physics B》 SCIE EI CAS CSCD 2005年第6期1077-1081,共5页
The phenomenon of stochastic resonance (SR) in a bistable system driven by multiplicative and additive white noises and a periodic rectangular signal with a constant component is studied according to the theory of sig... The phenomenon of stochastic resonance (SR) in a bistable system driven by multiplicative and additive white noises and a periodic rectangular signal with a constant component is studied according to the theory of signal-to-noise ratio (SNR) in the adiabatic limit. The analytic expression of the SNR is obtained for arbitrary signal amplitude without being restricted to small amplitudes. We find that the effects of the multiplicative noise intensity D and additive noise intensity α on SNR are different: the SNR-α curve shows SR for almost the whole range of static asymmetry r, but the SNR-D curve only displays SR for some values of static asymmetry r. It is more sensitive to control SR through adjusting the additive noise intensity a than adjusting the multiplicative noise intensity D, when the asymmetry of bistable potential r is not too large. Moreover, the static asymmetry r decreases the SNR. 展开更多
关键词 随机振动 对称双稳系统 信噪比 周期正交信号
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New families of non-travelling wave solutions to the (2+1)-dimensional modified dispersive water-wave system 被引量:7
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作者 李德生 张鸿庆 《Chinese Physics B》 SCIE EI CAS CSCD 2004年第9期1377-1381,共5页
In this paper, we introduce a further generalized projective Riccati equation method and apply it to solve the (2+1)-dimensional modified dispersive water-wave system. Many new types of non-travelling wave solutions a... In this paper, we introduce a further generalized projective Riccati equation method and apply it to solve the (2+1)-dimensional modified dispersive water-wave system. Many new types of non-travelling wave solutions are obtained for this system. 展开更多
关键词 三维修正水波扩散系统 非行波解 Riccati投射 水动力学
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Baecklund Transformation and Exact Solutions for a New Generalized Zakharov—Kuzentsov Equation with Nonlinear Terms of Any Order 被引量:7
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作者 CHENYong LIBiao 等 《Communications in Theoretical Physics》 SCIE CAS CSCD 2003年第2期135-140,共6页
In this paper,with the help of symbolic computation,a new Backlund transformation(BT)for a new generalized Zakharov-Kuznetsov equation with nonlinear term of any order,ut+aupux+bu2pux+γuxy+δuxxx+ρuxyy=0,is obtained... In this paper,with the help of symbolic computation,a new Backlund transformation(BT)for a new generalized Zakharov-Kuznetsov equation with nonlinear term of any order,ut+aupux+bu2pux+γuxy+δuxxx+ρuxyy=0,is obtained by using the homogeneous balance method.Based on the BT,some exact solutions are presented. 展开更多
关键词 非线偏微分方程 严格解 Zakharov-Kuzentsov方程
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A flower image retrieval method based on ROI feature 被引量:6
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作者 洪安祥 陈刚 +2 位作者 李均利 池哲儒 张亶 《Journal of Zhejiang University Science》 CSCD 2004年第7期764-772,共9页
Flower image retrieval is a very important step for computer-aided plant species recognition. In this paper, we propose an efficient segmentation method based on color clustering and domain knowledge to extract flower... Flower image retrieval is a very important step for computer-aided plant species recognition. In this paper, we propose an efficient segmentation method based on color clustering and domain knowledge to extract flower regions from flower images. For flower retrieval, we use the color histogram of a flower region to characterize the color features of flower and two shape-based features sets, Centroid-Contour Distance (CCD) and Angle Code Histogram (ACH), to characterize the shape features of a flower contour. Experimental results showed that our flower region extraction method based on color clustering and domain knowledge can produce accurate flower regions. Flower retrieval results on a database of 885 flower images collected from 14 plant species showed that our Region-of-Interest (ROI) based retrieval approach using both color and shape features can perform better than a method based on the global color histogram proposed by Swain and Ballard (1991) and a method based on domain knowledge-driven segmentation and color names proposed by Das et al.(1999). 展开更多
关键词 颜色特征 形状特征 知识驱动分割 花卉图像恢复 花卉图像表征 计算机辅助识别 植物种类
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On a New Modified Extended Tanh—Function Method 被引量:4
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作者 LUZHuo-Sheng ZHANGHong-Qing 《Communications in Theoretical Physics》 SCIE CAS CSCD 2003年第4期405-408,共4页
In this paper, a new modified extended tanh-function method is presented for constructing multiple soliton-like, periodic form and rational solutions of nonlinear evolution equations (NLEEs). This method is more power... In this paper, a new modified extended tanh-function method is presented for constructing multiple soliton-like, periodic form and rational solutions of nonlinear evolution equations (NLEEs). This method is more powerful thanthe extended tanh-function method [Phys. Lett. A277 (2000) 212] and the modified extended tanh-function method[Phys. Lett. A299 (2002) 179] Abundant new solutions of two physically important NLEEs are obtained by using thismethod and symbolic computation system Maple. 展开更多
关键词 孤波解 改进扩展双曲正切函数法 物理数学方法 微分方程
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A Series of Soliton-like and Double-like Periodic Solutions of a (2+1)-Dimensional Asymmetric Nizhnik-Novikov-Vesselov Equation 被引量:4
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作者 CHENYong WANGQi LIBiao 《Communications in Theoretical Physics》 SCIE CAS CSCD 2004年第5X期655-660,共6页
We generalize the algebraic method presented by Fan [J. Phys. A: Math. Gen. 36 (2003) 7009)] to uniformly construct a series of soliton-like solutions and double-like periodic solutions for nonlinear partial different... We generalize the algebraic method presented by Fan [J. Phys. A: Math. Gen. 36 (2003) 7009)] to uniformly construct a series of soliton-like solutions and double-like periodic solutions for nonlinear partial differential equations(NPDE). As an application of the method, we choose a (2+1)-dimensional asymmetric Nizhnik-Novikov-Vesselov equation and successfully construct new and more general solutions including a series of nontraveling wave and coefficient functions' soliton-like solutions, double-like periodic and trigonometric-like function solutions. 展开更多
关键词 符号运算 孤波解 椭圆方程 周期解 代数法
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Exact Solutions of the (3+1)—Dimensional KP and KdV—Type Equations 被引量:4
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作者 LIDe-Sheng LUZhuo-Sheng 《Communications in Theoretical Physics》 SCIE CAS CSCD 2003年第3期267-275,共9页
Abundant new soliton-like and period form solutions for certain (3+1)-dimensional physically important nonlinear evolution equations are obtained by using a further extended tanh method and symbolic computation system... Abundant new soliton-like and period form solutions for certain (3+1)-dimensional physically important nonlinear evolution equations are obtained by using a further extended tanh method and symbolic computation system, Maple. 展开更多
关键词 非线性偏微分方程 KDV型方程 严格解
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EXACT BOUNDS OF THE MODIFIED LPT ALGORITHMS APPLYING TO PARALLEL MACHINES SCHEDULING WITH NONSILMULTANEOUS MACHINE AVAILABLE TIMES 被引量:3
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作者 LINGUOHUI HeYong +1 位作者 YaoYuJun LuHatyan 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 1997年第1期109-116,共8页
In this paper, we consider Parallel Machines Scheduling with nonsimultaneous machine available time. We give the exact worst case performance bound of MLPT proposed by Lee. Furthermore, two other modified LPT algorith... In this paper, we consider Parallel Machines Scheduling with nonsimultaneous machine available time. We give the exact worst case performance bound of MLPT proposed by Lee. Furthermore, two other modified LPT algorithms are discussed. The paper is ended by numerical ex-periments of these algorithms. 展开更多
关键词 LPT算法 机器调度 非奇异性 可用时间
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Genetic Searching Algorithm for Optimal Runlength-Limited Codes with Error Control 被引量:5
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作者 RenQingsheng YeZhongxing 《通信学报》 EI CSCD 北大核心 1997年第3期54-59,共6页
GeneticSearchingAlgorithmforOptimalRunlength┐LimitedCodeswithErrorControl**ThisworkwassupportedbytheChineseK... GeneticSearchingAlgorithmforOptimalRunlength┐LimitedCodeswithErrorControl**ThisworkwassupportedbytheChineseKeyProjectofFundam... 展开更多
关键词 基因算法 分组码 信号处理
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Solving Integrable Broer-Kaup Equations in (2+1)-Dimensional Spaces via an Improved Variable Separation Approach 被引量:3
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作者 LIDe-Sheng LUOCheng-Xin ZHANGHong-Qing 《Communications in Theoretical Physics》 SCIE CAS CSCD 2004年第1X期1-3,共3页
Starting from Backlund transformation and using Cole-Hopf transformation, we reduce the integrable Broer-Kaup equations in (2+1)-dimensional spaces to a simple linear evolution equation with two arbitrary functions of... Starting from Backlund transformation and using Cole-Hopf transformation, we reduce the integrable Broer-Kaup equations in (2+1)-dimensional spaces to a simple linear evolution equation with two arbitrary functions of {x,t} and {y,t} in this paper. And we can obtain some new solutions of the original equations by investigating the simple nonlinear evolution equation, which include the solutions obtained by the variable separation approach. 展开更多
关键词 可积三维空间Broer-Kaup方程 相干结构 变量分离近似 Cole-Hopf变换
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On the Spectral Radius of Trees with the Given Diameter d 被引量:3
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作者 TANShang-wang GUOJi-ming QIJian 《Chinese Quarterly Journal of Mathematics》 CSCD 2004年第1期57-62,共6页
Let T denote a tree with the diameter d(d≥2) and order n. Let P^*d,r,n-d-1denote the tree obtained by identifying the rth vertex of path Pd+l and the center of starKl,K1,n-d-1, where r = r(d) is the integer part abou... Let T denote a tree with the diameter d(d≥2) and order n. Let P^*d,r,n-d-1denote the tree obtained by identifying the rth vertex of path Pd+l and the center of starKl,K1,n-d-1, where r = r(d) is the integer part about d+2/2. Then p(T)≤ p(P^*d,r,n-d-1), andequality holds if and only if T≌P^*d,r。 展开更多
关键词 图论 整数 顶点 通道
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