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BO方程的同宿呼吸波和有理波及其扰动动力学行为
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作者 宋莉莉 蒲志林 鲜大权 《量子电子学报》 CSCD 北大核心 2017年第5期550-556,共7页
针对(1+1)维Benjamin-Ono(BO)方程,应用初值扰动双线性变换,结合同宿测试法获得了新的初值扰动周期呼吸波解和扭结呼吸波解,结合二次函数拟设法获得了初值扰动有理波解及其动力学分叉点。直观展示了一些动力学局域扰动结构,结果表明了... 针对(1+1)维Benjamin-Ono(BO)方程,应用初值扰动双线性变换,结合同宿测试法获得了新的初值扰动周期呼吸波解和扭结呼吸波解,结合二次函数拟设法获得了初值扰动有理波解及其动力学分叉点。直观展示了一些动力学局域扰动结构,结果表明了该方程动力学行为对初值的敏感性。 展开更多
关键词 非线性方程 BENJAMIN-ONO方程 同宿呼吸 有理波 动力学扰动
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过完备有理小波变换在轴承故障诊断中的应用 被引量:5
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作者 毛永芳 秦毅 汤宝平 《振动.测试与诊断》 EI CSCD 北大核心 2011年第5期626-630,667,共5页
利用过完备有理离散小波变换的滤波器特性和近似平移不变性,提出了一种按一定规则对3路高频小波分量进行拼接,以获得具有更高时间分辨率小波分量信号的方法。仿真结果表明,该方法消除了小波分解中下采样对信号分析的影响,较好地克服了... 利用过完备有理离散小波变换的滤波器特性和近似平移不变性,提出了一种按一定规则对3路高频小波分量进行拼接,以获得具有更高时间分辨率小波分量信号的方法。仿真结果表明,该方法消除了小波分解中下采样对信号分析的影响,较好地克服了频率混叠现象。在此基础上,提出了一种基于过完备有理离散小波变换的故障诊断方法,并将其应用于滚动轴承早期故障诊断。与二进离散小波变换的比较试验结果表明,有理离散小波变换能更有效地提取出滚动轴承的早期故障特征。 展开更多
关键词 过完备有理离散小变换 滚动轴承 故障诊断
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基于有理Haar小波求解分数阶第2类Fredholm积分方程 被引量:5
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作者 张倩 韩惠丽 张盼盼 《江西师范大学学报(自然科学版)》 CAS 北大核心 2014年第1期47-50,82,共5页
利用有理Haar小波函数数值求解分数阶第2类Fredholm积分方程,用有理Haar小波定义及性质与配置法给出有理Haar小波积分算子矩阵,将积分方程转化为代数方程组进行求解.最后通过误差分析和数值算例将分数阶积分方程的精确解和用Haar小波所... 利用有理Haar小波函数数值求解分数阶第2类Fredholm积分方程,用有理Haar小波定义及性质与配置法给出有理Haar小波积分算子矩阵,将积分方程转化为代数方程组进行求解.最后通过误差分析和数值算例将分数阶积分方程的精确解和用Haar小波所得数值解进行比较,表明了该算法具有较高的精确度. 展开更多
关键词 有理Haar小 分数阶 第2类Fredholm积分方程 配置法
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偶数长有理数对称紧支双正交小波滤波器设计 被引量:2
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作者 韩芳芳 段发阶 +1 位作者 张宝峰 段晓杰 《计算机工程与应用》 CSCD 北大核心 2010年第31期10-13,共4页
基于Daubechies紧支集小波构造方法所得到的小波滤波器多为非线性相位和无理数系数。非线性相位滤波器在图像处理过程中容易引起失真,而无理系数滤波器给小波变换的应用尤其是在算法的硬件实现方面带来不便。借助完全重构滤波器思想,进... 基于Daubechies紧支集小波构造方法所得到的小波滤波器多为非线性相位和无理数系数。非线性相位滤波器在图像处理过程中容易引起失真,而无理系数滤波器给小波变换的应用尤其是在算法的硬件实现方面带来不便。借助完全重构滤波器思想,进行了具有线性相位的双正交小波滤波器设计,同时通过添加消失矩特性条件,归纳推导出偶数长有理系数双正交对称紧支集小波滤波器的构造方法。以长度为8-4双正交小波设计为例,对设计方程中出现的自由变量的取值范围进行了讨论,得到了8-4有理系数双正交对称小波滤波器。 展开更多
关键词 器构造 有理系数小 偶数长滤 双正交小 变换
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半参数回归模型中的Haar有理小波去噪方法
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作者 徐建成 《湖北师范学院学报(自然科学版)》 2007年第2期54-57,72,共5页
将Haar有理小波方法应用于半参数回归模型的参数与非参数估计,并进行了数值模拟,得到较好的结果。
关键词 半参数回归 参数估计 非参数估计 Haar有理 去噪
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n阶Fredholm积分-微分方程的有理Haar小波解法
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作者 张建平 《价值工程》 2012年第23期268-269,共2页
一阶积分-微分方程是我们求解积分微分方程时常见的一类方程,其求解方法比较简单;而在实际问题中我们常常会遇到高阶积分-微分方程的求解,求其数值解相对比较困难。作者利用有理Haar小波的积分法和积分算子矩阵对一般的n阶Fredholm积分... 一阶积分-微分方程是我们求解积分微分方程时常见的一类方程,其求解方法比较简单;而在实际问题中我们常常会遇到高阶积分-微分方程的求解,求其数值解相对比较困难。作者利用有理Haar小波的积分法和积分算子矩阵对一般的n阶Fredholm积分-微分方程进行了求解。最后给出的数值算例表明了该方法的有效性。 展开更多
关键词 积分-微分方程 有理Haar小 算子矩阵
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基于有理双树复小波和SVM的滚动轴承故诊断方法 被引量:2
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作者 孙珊珊 何光辉 崔建 《计算机科学》 CSCD 北大核心 2015年第B11期131-134,共4页
滚动轴承故障类型被支持向量机(SVM)智能识别的关键是故障特征的提取。为了提取最优的故障特征,提高SVM的分类识别精度,提出了基于有理双树复小波和SVM的滚动轴承故障诊断方法。首先通过双树复小波包变换将非平稳的振动信号分解得到不... 滚动轴承故障类型被支持向量机(SVM)智能识别的关键是故障特征的提取。为了提取最优的故障特征,提高SVM的分类识别精度,提出了基于有理双树复小波和SVM的滚动轴承故障诊断方法。首先通过双树复小波包变换将非平稳的振动信号分解得到不同频带的分量,然后对每个分量求能量并作归一化处理,最后将从各个频带分量中提取的能量特征参数作为支持向量机的输入来识别滚动轴承的故障类型。研究结果表明该方法可以有效、准确地识别轴承的故障模式。 展开更多
关键词 有理双树复小变换 特征提取 支持向量机 滚动轴承 故障分类
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有理Haar小波求解非线性分数阶Fredholm积分微分方程
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作者 黄洁 韩惠丽 梁亮 《吉林大学学报(理学版)》 CAS CSCD 北大核心 2015年第5期868-872,共5页
利用有理Haar小波的分数阶积分算子矩阵,提出一种求解非线性分数阶Fredholm积分微分方程的数值算法,并通过数值实验验证了所提算法的精确性和有效性.
关键词 有理Haar小 Fredholm积分微分方程 分数阶微积分
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一类非线性波动方程新的显式精确解 被引量:1
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作者 刘煜 范立群 《河南科技大学学报(自然科学版)》 CAS 2008年第6期83-85,92,共4页
利用积分法和试探函数法求出了非线性波动方程utt-kuxx+pu+qu2+su3=0多个新的显式精确解,其中包括双曲函数型孤立波解、三角函数周期波解,特别是得到了该方程的有理函数型孤立波解,用试探函数法求出的一类解代表了任意多组解,由该类解... 利用积分法和试探函数法求出了非线性波动方程utt-kuxx+pu+qu2+su3=0多个新的显式精确解,其中包括双曲函数型孤立波解、三角函数周期波解,特别是得到了该方程的有理函数型孤立波解,用试探函数法求出的一类解代表了任意多组解,由该类解可以化出扭状孤波解和奇异行波解。 展开更多
关键词 非线性动方程 孤立 有理函数型孤立 扭状孤 奇异行
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Volterra积分方程的Haar小波解
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作者 刘江 《纺织高校基础科学学报》 CAS 2011年第1期53-56,共4页
给出了一种有效求解第一型Volterra积分方程的方法.以有理Haar小波作为逼近函数,利用小波配置方法,将第一型Volterra积分方程的近似求解问题转化为线性方程组求解.进而,得到原方程的近似解.数值算例表明了该方法的可行性和精确性.
关键词 有理Haar小 近似解 第一型Volterra积分方程
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扩展的Riccati方法与Kupershmidt方程新的显式精确行波解
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作者 夏铁成 《锦州师范学院学报(自然科学版)》 2003年第4期32-35,共4页
关键词 Riccati方法 KUPERSHMIDT方程 吴方法 奇性孤 周期 有理函数 非线性偏微分方程
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Efficient rendering of breaking waves using MPS method 被引量:9
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作者 WANG Qiang ZHENG Yao +2 位作者 CHEN Chun FUJIMOTO Tadahiro CHIBA Norishige 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2006年第6期1018-1025,共8页
This paper proposes an approach for rendering breaking waves out of large-scale of particle-based simulation. Moving particle semi-implicit (MPS) is used to solve the governing equation, and 2D simulation is expanded ... This paper proposes an approach for rendering breaking waves out of large-scale of particle-based simulation. Moving particle semi-implicit (MPS) is used to solve the governing equation, and 2D simulation is expanded to 3D representation by giving motion variation using fractional Brownian motion (fBm). The waterbody surface is reconstructed from the outlines of 2D simulation. The splashing effect is computed according to the properties of the particles. Realistic features of the wave are ren-dered on GPU, including the reflective and refractive effect and the effect of splash. Experiments showed that the proposed method can simulate large scale breaking waves efficiently. 展开更多
关键词 Moving particle semi-implicit (MPS) Particle-system Surface reconstruction
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Rational and Periodic Wave Solutions of Two-Dimensional Boussinesq Equation 被引量:3
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作者 ZHANG yi YE Ling-Ya 《Communications in Theoretical Physics》 SCIE CAS CSCD 2008年第4期815-824,共10页
Two new exact, rational and periodic wave solutions are derived for the two-dimensional Boussinesq equation. For the first solution it is obtained by performing an appropriate limiting procedure on the soliton solutio... Two new exact, rational and periodic wave solutions are derived for the two-dimensional Boussinesq equation. For the first solution it is obtained by performing an appropriate limiting procedure on the soliton solutions obtained by Hirota bilinear method. The second one in terms of Riemann theta function is explicitly presented by virtue of Hirota bilinear method and its asymptotic property is also analyzed in detail. Moreover, it is of interest to note that classical soliton solutions can be reduced from the periodic wave solutions. 展开更多
关键词 SOLITON Hirota bilinear method Riemann theta function periodic wave solutions rational solutions two-dimensional Boussinesq equation
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New rational form solutions to mKdV equation 被引量:3
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作者 FUZun-Tao LIUShi-Kuo LIUShi-Da 《Communications in Theoretical Physics》 SCIE CAS CSCD 2005年第3期423-426,共4页
In this paper, new basic functions, which are composed of three basic Jacobi elliptic functions, are chosen as components of finite expansion. This finite expansion can be taken as an ansatz and applied to solve nonli... In this paper, new basic functions, which are composed of three basic Jacobi elliptic functions, are chosen as components of finite expansion. This finite expansion can be taken as an ansatz and applied to solve nonlinear wave equations. As an example, mKdV equation is solved, and more new rational form solutions are derived, such as periodic solutions of rational form, solitary wave solutions of rational form, and so on. 展开更多
关键词 elliptic equation Jacobi elliptic function periodic wave solution rational form
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New Explicit Rational Solitary Wave Solutions for Discretized mKdV Lattice Equation 被引量:2
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作者 YU Ya-Xuan WANG Qi ZHANG Hong-Qing 《Communications in Theoretical Physics》 SCIE CAS CSCD 2005年第6X期1011-1014,共4页
In this letter, we study discretized mKdV lattice equation by using a new generalized ansatz. As a result,many explicit rational exact solutions, including some new solitary wave solutions, are obtained by symbolic co... In this letter, we study discretized mKdV lattice equation by using a new generalized ansatz. As a result,many explicit rational exact solutions, including some new solitary wave solutions, are obtained by symbolic computation code Maple. 展开更多
关键词 differential-difference equations discretized mKdV lattice equation solitary wave solution rational expand method
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A New Rational Algebraic Approach to Find Exact Analytical Solutions to a (2+1)-Dimensional System 被引量:7
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作者 BAI Cheng-Jie ZHAO Hong 《Communications in Theoretical Physics》 SCIE CAS CSCD 2007年第5X期801-810,共10页
In this paper, we present a new rational algebraic approach to uniformly construct a series of exact analytical solutions for nonlinear partial differential equations. Compared with most existing tanh methods and othe... In this paper, we present a new rational algebraic approach to uniformly construct a series of exact analytical solutions for nonlinear partial differential equations. Compared with most existing tanh methods and other sophisticated methods, the proposed method not only recovers some known solutions, but also finds some new and general solutions. The solutions obtained in this paper include rational form triangular periodic wave solutions, solitary wave solutions, and elliptic doubly periodic wave solutions. The efficiency of the method can be demonstrated on (2+1)-dimensional dispersive long-wave equation. 展开更多
关键词 rational algebraic approach (2+1)-dimensional dispersive long-wave equation exact solutions
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Empirical formula for wave length of ocean wave in finite depth water 被引量:1
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作者 管长龙 鞠红梅 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2005年第1期17-21,共5页
In this paper, function characteristics of dispersion of ocean wave in finite depth water were analyzed systematically. The functional form of the fitting function is reasonably proposed, in which the parame- ters are... In this paper, function characteristics of dispersion of ocean wave in finite depth water were analyzed systematically. The functional form of the fitting function is reasonably proposed, in which the parame- ters are optimally determined by the least square method (LSM). For infinitely deep and extremely shallow water, the fitting function fits strictly the dispersion to be fitted. A new technique is presented in application of LSM. An empirical formula with maximum error of less than 0.5% for computing wavelength in finite depth water is presented for practical applications. 展开更多
关键词 WAVELENGTH ocean wave finite depth water
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Characteristics of surface waves in anisotropic left-handed materials 被引量:1
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作者 姜永远 时红艳 +2 位作者 张永强 侯春风 孙秀冬 《Chinese Physics B》 SCIE EI CAS CSCD 2007年第7期1959-1962,共4页
We report the coexistence of TE and TM surface modes in certain same frequency domain at the interface between one isotropic regular medium and another biaxially anistotropic left-handed medium. The conditions for the... We report the coexistence of TE and TM surface modes in certain same frequency domain at the interface between one isotropic regular medium and another biaxially anistotropic left-handed medium. The conditions for the existence of TE and TM polarized surface waves in biaxially anisotropic left-handed materials are identified, respectively. The Poynting vector and the energy density associated with surface modes are calculated. Depending on the system parameters, either TE or TM surface modes can have the time averaged Poynting vector directed to or opposite to the mode phase velocity. It is seen that the characteristics of surface waves in biaxially anisotropic left-handed media are significantly different from that in isotropic left-handed media. 展开更多
关键词 biaxially anisotropic left-handed material surface wave dispersion relation
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New Rational Form Solutions to Coupled Nonlinear Wave Equations
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作者 FU Zun-Tao LIN Guang-Xing +1 位作者 LIU Shi-Kuo LIU Shi-Da 《Communications in Theoretical Physics》 SCIE CAS CSCD 2005年第2X期235-242,共8页
The new rational form solutions to the elliptic equation are shown, and then these solutions to the elliptic equation are taken as a transformation and applied to solve nonlinear coupled wave equations. It is shown th... The new rational form solutions to the elliptic equation are shown, and then these solutions to the elliptic equation are taken as a transformation and applied to solve nonlinear coupled wave equations. It is shown that more novel kinds of solutions are derived, such as periodic solutions of rational form, solitary wave solutions of rational form,and so on. 展开更多
关键词 elliptic equation Jacobi elliptic function nonlinear coupled equations periodic wave solution rational form
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Effective Management of Own Funds in Polish Cooperative Banks
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作者 Rafal Balina Olaf Kowalski Jerzy Rozynski 《Chinese Business Review》 2014年第3期154-161,共8页
Today cooperative banks belong to the most significant financial institution in the world. Moreover, they can compete with commercial banks. The own funds of the cooperative bank are important in their activity. The m... Today cooperative banks belong to the most significant financial institution in the world. Moreover, they can compete with commercial banks. The own funds of the cooperative bank are important in their activity. The main goal of this paper is to investigate how much the level of the own funds of the Polish cooperative banks influenced their efficiency. The research pertained to operating cooperative banks in Poland. The following measures of the efficiency were used in the research: return on Equity (ROE), net profit, index C/I, and financial margin. The results of the study indicate that banks from the Quartile III (highest aggregate own funds), had the highest net profits, the highest ROE, the lowest C/I value, the lowest ROE, and the lowest financial markups. On this basis, it remains to be recommended that banks of highest aggregate own funds continue expansion of own funds which will increase lending capacity and subsequently contribute to higher effectiveness. 展开更多
关键词 cooperative bank own funds EFFECTIVENESS
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