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Positon and hybrid solutions for the(2+1)-dimensional complex modified Korteweg-de Vries equations 被引量:1
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作者 袁丰 Behzad Ghanbari 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第4期118-124,共7页
Solving nonlinear partial differential equations have attracted intensive attention in the past few decades. In this paper, the Darboux transformation method is used to derive several positon and hybrid solutions for ... Solving nonlinear partial differential equations have attracted intensive attention in the past few decades. In this paper, the Darboux transformation method is used to derive several positon and hybrid solutions for the(2+1)-dimensional complex modified Korteweg–de Vries equations. Based on the zero seed solution, the positon solution and the hybrid solutions of positon and soliton are constructed. The composition of positons is studied, showing that multi-positons of(2+1)-dimensional equations are decomposed into multi-solitons as well as the(1+1)-dimensions. Moreover, the interactions between positon and soliton are analyzed. In addition, the hybrid solutions of b-positon and breather are obtained using the plane wave seed solution, and their evolutions with time are discussed. 展开更多
关键词 positon solution b-positon solution breather solution the hybrid solution the Darboux transformation
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Nonsingular Positon Solutions of a Variable-Coefficient Modified KdV Equation 被引量:1
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作者 Yi Lin Chuanzhong Li Jingsong He 《Open Journal of Applied Sciences》 2013年第1期102-105,共4页
The determinant representation of three-fold Darboux transformation for a variable-coefficient modified KdV equation is displayed based on the technique used to solve Ablowitz-Kaup-Newell-Segur system. Additionally, t... The determinant representation of three-fold Darboux transformation for a variable-coefficient modified KdV equation is displayed based on the technique used to solve Ablowitz-Kaup-Newell-Segur system. Additionally, the nonsingular positon solutions of the variable-coefficient modified KdV equation are firstly discovered analytically and graphically. 展开更多
关键词 VARIABLE-COEFFICIENT KdV Equation LAX Pair DARBOUX Transformation positon Soliton-positon
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Soliton molecules and dynamics of the smooth positon for the Gerdjikov–Ivanov equation 被引量:2
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作者 Xiangyu Yang Zhao Zhang Biao Li 《Chinese Physics B》 SCIE EI CAS CSCD 2020年第10期180-185,共6页
Soliton molecules are firstly obtained by velocity resonance for the Gerdjikov–Ivanov equation, and n-order smooth positon solutions for the Gerdjikov–Ivanov equation are generated by means of the general determinan... Soliton molecules are firstly obtained by velocity resonance for the Gerdjikov–Ivanov equation, and n-order smooth positon solutions for the Gerdjikov–Ivanov equation are generated by means of the general determinant expression of n-soliton solution. The dynamics of the smooth positons of the Gerdjikov–Ivanov equation are discussed using the decomposition of the modulus square, the trajectories and time-dependent "phase shifts" of positons after the collision can be described approximately. Additionally, some novel hybrid solutions consisting solitons and positons are presented and their rather complicated dynamics are revealed. 展开更多
关键词 soliton molecules degenerate Darboux transformation positons phase shift Gerdjikov-Ivanov equation
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Soliton, Positon and Negaton Solutions of Extended KdV Equation
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作者 WU Hong-Xia ZENG Yun-Bo FAN Tian-You 《Communications in Theoretical Physics》 SCIE CAS CSCD 2008年第3期529-534,共6页
Darboux transformation (DT) provides us with a comprehensive approach to construct the exact and explicit solutions to the negative extended KdV (eKdV) equation, by which some new solutions such as singular solito... Darboux transformation (DT) provides us with a comprehensive approach to construct the exact and explicit solutions to the negative extended KdV (eKdV) equation, by which some new solutions such as singular soliton, negaton, and positon solutions are computed for the eKdV equation. We rediscover the soliton solution with finiteamplitude in [A.V. Slyunyaev and E.N. Pelinovskii, J. Exp. Theor. Phys. 89 (1999) 173] and discuss the difference between this soliton and the singular soliton. We clarify the relationship between the exact solutions of the eKdV equation and the spectral parameter. Moreover, the interactions of singular two solitons, positon and negaton, positon and soliton, and two positons are studied in detail. 展开更多
关键词 the extended KdV equation singular soliton positon NEGATON Darboux transformation
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Negatons, Positons, and Complexiton Solutions of Higher Order for a Non-isospectral KdV Equation
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作者 ZHANG Yuan-Yuan WANG Qi ZHANG Hong-Qing 《Communications in Theoretical Physics》 SCIE CAS CSCD 2007年第3X期411-414,共4页
In this paper, negatons, positons, and complexiton solutions of higher order for a non-isospectral KdV equation, the KdV equation with loss and non-uniformity terms are obtained through the bilinear Baicklund transfor... In this paper, negatons, positons, and complexiton solutions of higher order for a non-isospectral KdV equation, the KdV equation with loss and non-uniformity terms are obtained through the bilinear Baicklund transformation. Further, the properties of some solutions are shown by some figures made by using Maple. 展开更多
关键词 bilinear Backlund transformation negatons positons complexiton solutions
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奇异Semi-Positone边值问题正解存在性 被引量:1
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作者 柴国庆 《数学学报(中文版)》 SCIE CSCD 北大核心 2004年第6期1167-1174,共8页
考虑奇异Semi-Positone边值问题y″=f(t,y,y′),t∈(0,1),y(0)=a>0, y(1)=0,并应用Schauder不动点定理,在适当的条件下,建立了正解存在性定理.
关键词 Semi-positone边值问题 正解 存在性
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Smooth Positons of the Second-Type Derivative Nonlinear Schr?dinger Equation
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作者 Shu-Zhi Liu Yong-Shuai Zhang Jing-Song He 《Communications in Theoretical Physics》 SCIE CAS CSCD 2019年第4期357-361,共5页
We construct the soliton solution and smooth positon solution of the second-type derivative nonlinear Schr¨odinger(DNLSII) equation. Additionally, we present a detailed discussion about the decomposition of the p... We construct the soliton solution and smooth positon solution of the second-type derivative nonlinear Schr¨odinger(DNLSII) equation. Additionally, we present a detailed discussion about the decomposition of the positon solution, and display its approximate orbits and variable "phase shift". The second and third order breather-positon solutions are also constructed. 展开更多
关键词 Chen-Lee-Liu EQUATION positon breather-positon Daroboux transformation
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Dynamics of the Smooth Positons of the Wadati-Konno-Ichikawa Equation
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作者 Gai-Hua Wang Yong-Shuai Zhang Jing-Song He 《Communications in Theoretical Physics》 SCIE CAS CSCD 2018年第3期227-232,共6页
We discuss a modified Wadati-Konno-Ichikawa(m WKI)equation,which is equivalent to the WKI equation by a hodograph transformation.The explicit formula of degenerated solution of m WKI equation is provided by using dege... We discuss a modified Wadati-Konno-Ichikawa(m WKI)equation,which is equivalent to the WKI equation by a hodograph transformation.The explicit formula of degenerated solution of m WKI equation is provided by using degenerate Darboux transformation with respect to the eigenvalues,which yields two kinds of smooth solutions possessing the vanishing and nonvanishing boundary conditions respectively.In particular,a method for the decomposition of modulus square is operated to the positon solution,and the approximate orbits before and after collision of positon solutions are displayed explicitly. 展开更多
关键词 Wadati-Konno-Ichikawa equation positon breather-positon TRAJECTORY phase shift
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Higher-order smooth positons and breather positons of Sine-Gordon equation
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作者 Lin Jiang Biao Li 《Communications in Theoretical Physics》 SCIE CAS CSCD 2022年第8期51-55,共5页
According to the N-soliton solution derived from Hirota's bilinear method,higher-order smooth positons and breather positons are obtained efficiently through an ingenious limit approach.This paper takes the Sine-G... According to the N-soliton solution derived from Hirota's bilinear method,higher-order smooth positons and breather positons are obtained efficiently through an ingenious limit approach.This paper takes the Sine-Gordon equation as an example to introduce how to utilize this technique to generate these higher-order smooth positons and breather positons in detail.The dynamical behaviors of smooth positons and breather positons are presented by some figures.During the procedure of deduction,the approach mentioned has the strengths of concision and celerity.In terms of feasibility and practicability,this approach can be exploited widely to study higherorder smooth positons and breather positons of other integrable systems. 展开更多
关键词 Hirota's bilinear method smooth positons breather positons
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Multiple Positive Solutions for Semi-positone m-point Boundary Value Problems 被引量:1
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作者 Cheng-bo Zhai Cheng Yang 《Acta Mathematicae Applicatae Sinica》 SCIE CSCD 2011年第3期419-426,共8页
In this article, we establish the existence of at least two positive solutions for the semi-positone m-point boundary value problem with a parameter u (t) + λf (t, u) = 0, t ∈ (0, 1), u (0) = sum (biu (ξ... In this article, we establish the existence of at least two positive solutions for the semi-positone m-point boundary value problem with a parameter u (t) + λf (t, u) = 0, t ∈ (0, 1), u (0) = sum (biu (ξ i )) from i=1 to m-2, u(1)= sum (aiu(ξ i )) from i=1 to m-2, where λ 〉 0 is a parameter, 0 〈 ξ 1 〈 ξ 2 〈 ··· 〈 ξ m 2 〈 1 with 0 〈sum ai from i=1 to m-2 〈 1, sum bi from i=1 to m-2 =1 b i 〈 1, a i , b i ∈ [0, ∞) and f (t, u) ≥ M with M is a positive constant. The method employed is the Leggett-Williams fixed-point theorem. As an application, an example is given to demonstrate the main result. 展开更多
关键词 Multiple positive solutions CONE semi-positone m-point boundary value problem concave functional PARAMETER
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Darboux transformation and positons of the inhomogeneous Hirota and the Maxwell-Bloch equation
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作者 LI ChuanZhong HE JingSong 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS 2014年第5期898-907,共10页
In this paper,we derive Darboux transformation of the inhomogeneous Hirota and the Maxwell-Bloch(IH-MB)equations which are governed by femtosecond pulse propagation through inhomogeneous doped fibre.The determinant re... In this paper,we derive Darboux transformation of the inhomogeneous Hirota and the Maxwell-Bloch(IH-MB)equations which are governed by femtosecond pulse propagation through inhomogeneous doped fibre.The determinant representation of Darboux transformation is used to derive soliton solutions,positon solutions to the IH-MB equations. 展开更多
关键词 inhomogeneous Hirota and Maxwell-Bloch equations Darboux transformation soliton solution positon solution
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Positive Solutions of Sub-Linear Semi-Positone Boundary Value Problem System
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作者 XU Xi An 《Journal of Mathematical Research and Exposition》 CSCD 北大核心 2008年第2期305-315,共11页
In this paper, we study the existence of positive solutions of a sub-linear semi-positone differential boundary value problems system with positive parameter. We prove that the semipositone differential boundary value... In this paper, we study the existence of positive solutions of a sub-linear semi-positone differential boundary value problems system with positive parameter. We prove that the semipositone differential boundary value problems system has at least one positive solution for the parameter sufficiently large. 展开更多
关键词 semi-positone differential boundary value problems system the fixed point index positive solutions
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Existence of Nonnegative Solutions to Singular Semi-positone Problems 被引量:1
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作者 Hong-zhou Wang, Li-hu Deng, Wei-gao GeDepartment of Applied Mathematics, Beijing Institute of Technology, Beijing 100081, China 《Acta Mathematicae Applicatae Sinica》 SCIE CSCD 2002年第3期523-528,共6页
In this paper we study a class of semi-positone singular boundary value problem. With prior bounds estimate and topology degree method, some existence results of nonnegative solution will be shown.
关键词 Semi-positone problem SINGULARITY Green function
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高压输电线路无线电干扰和电磁散射对GPS卫星信号影响测试及分析 被引量:24
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作者 刘兴发 尹晖 +3 位作者 邬雄 张建功 裴春明 干喆渊 《高电压技术》 EI CAS CSCD 北大核心 2011年第12期2937-2944,共8页
为分析高压输电线路对邻近作业全球定位系统(GPS)接收信号的影响,从高压输电线路发出的无线电干扰和线路对GPS卫星信号的散射两方面分析了高压输电线路对GPS接收装置观测信号的影响。高压输电线路导线电晕产生无线电干扰主要集中在10MH... 为分析高压输电线路对邻近作业全球定位系统(GPS)接收信号的影响,从高压输电线路发出的无线电干扰和线路对GPS卫星信号的散射两方面分析了高压输电线路对GPS接收装置观测信号的影响。高压输电线路导线电晕产生无线电干扰主要集中在10MHz以下,通过比较高压输电线路带电前后的定位误差,分析了高压输电线路对GPS接收信号的影响;高压输电线路作为大型构架对GPS卫星信号产生散射,改变卫星信号的幅值、相位和路径,GPS接收装置可能产生定位误差。通过比较离开高压输电线路不同距离测点的定位误差,分析了高压输电线路对GPS接收信号的影响。在交流特高压试验线段下进行现场试验,获得了试验线段带电和不带电运行2种工况下24个测点定位数据。试验结果表明,随着测点离开试验线段0、30、60、120、180m,坐标精度没有明显降低,与距离远近和线路是否带电运行没有明显规律。高压输电线路对邻近作业的GPS接收信号没有影响。 展开更多
关键词 高压输电线路 全球定位系统(GPS) 无线电干扰 电磁散射 定位精度影响 载波相位定位
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不同体位下气腹对妇科手术患者S100β蛋白和MMSE评分的影响 被引量:13
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作者 李陆军 史宏伟 +3 位作者 孙振全 曹雪莲 赵灵芝 季娟 《临床麻醉学杂志》 CAS CSCD 北大核心 2013年第11期1064-1066,共3页
目的研究不同Trendelenburg体位下气腹对妇科手术患者S100β蛋白和MMSE评分的影响。方法妇科腹腔镜手术患者60例,ASAI或Ⅱ级,随机均分为两组,Trendelenburg体位角度分别为20°组(T20组)和40°组(T40组)。记录麻醉诱导后... 目的研究不同Trendelenburg体位下气腹对妇科手术患者S100β蛋白和MMSE评分的影响。方法妇科腹腔镜手术患者60例,ASAI或Ⅱ级,随机均分为两组,Trendelenburg体位角度分别为20°组(T20组)和40°组(T40组)。记录麻醉诱导后(T2)、体位10min(R)、放气10min后(T3)和术后1h(rr4)的血清S100β蛋白含量,记录术前、术后1、6、12、24h的MMSE评分。结果T1~T4时两组血清S100β蛋白含量组间组内差异均无统计学意义。两组不同时点MMSE评分差异无统计学意义。结论Trendelenburg体位角度对妇科腹腔镜手术患者S100β蛋白和MMSE评分无明显影响。 展开更多
关键词 S100Β蛋白 CO2气腹Trendelenburg体位 认知功能障碍
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爬行式全位置弧焊机器人 被引量:8
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作者 潘际銮 阎炳义 +3 位作者 高力生 张华 卢勤英 金珂 《电焊机》 2005年第6期1-5,共5页
简述了焊接工艺过程自动化的必要性和国内外发展现状。重点介绍了大型工件工地焊接用爬行式全位置弧焊机器人的研究和开发。设计思路新颖,设计方案合理,自动化程度高。实验结果证明样机运行平稳、可靠,具有很好的跟踪精度。研究成果在... 简述了焊接工艺过程自动化的必要性和国内外发展现状。重点介绍了大型工件工地焊接用爬行式全位置弧焊机器人的研究和开发。设计思路新颖,设计方案合理,自动化程度高。实验结果证明样机运行平稳、可靠,具有很好的跟踪精度。研究成果在国内外弧焊过程自动化方面处于领先地位。 展开更多
关键词 电孤焊 自动化 爬行式 全位置 机器人
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六杆机构四位置运动生成的解域综合理论与方法 被引量:11
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作者 韩建友 崔光珍 杨通 《北京航空航天大学学报》 EI CAS CSCD 北大核心 2014年第9期1170-1175,共6页
针对Stephenson-Ⅱ型六杆机构四位置运动生成问题,给出基于布氏曲线的广义布氏曲线概念及其方程,同时给出解域综合方法.该方法首先求解出满足要求的解曲线,而后利用雅可比矩阵行列式值符号及机构运动连续性条件剔除解域中存在运动缺陷... 针对Stephenson-Ⅱ型六杆机构四位置运动生成问题,给出基于布氏曲线的广义布氏曲线概念及其方程,同时给出解域综合方法.该方法首先求解出满足要求的解曲线,而后利用雅可比矩阵行列式值符号及机构运动连续性条件剔除解域中存在运动缺陷的机构,最后根据实际需求附加约束条件形成可行解域图.给出的综合示例验证了解域综合方法的可行性和有效性.该方法简单且便于编程实现,同时对其他多杆机构的综合也有参考借鉴意义. 展开更多
关键词 六杆机构 运动生成 四位置综合 解曲线 解域
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航天用系列行波型超声波电机的研制 被引量:5
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作者 郭吉丰 王光庆 +3 位作者 沈润杰 傅平 周静 孙华君 《宇航学报》 EI CAS CSCD 北大核心 2007年第1期171-177,共7页
简述了超声波电机在航天领域的应用情况,并介绍了所研制的系列行波型超声波电机(直径分别为80mm、60mm、45mm和30mm)的结构形式、摩擦材料、粘结工艺、温度特性、机械特性和瞬态特性,提出了神经元自适应PID算法实现高精度的速度和位置... 简述了超声波电机在航天领域的应用情况,并介绍了所研制的系列行波型超声波电机(直径分别为80mm、60mm、45mm和30mm)的结构形式、摩擦材料、粘结工艺、温度特性、机械特性和瞬态特性,提出了神经元自适应PID算法实现高精度的速度和位置控制。结果表明其具有良好的特性,适用于空间机器人、登月车、太阳能帆板、CCD等空间机构的驱动,并结合航天领域的应用要求,提出了下一步的研究重点。 展开更多
关键词 行波型超声波电机 结构设计 机械特性 瞬态特性 控制特性 航天
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局部放电全站定位综合算法 被引量:4
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作者 刘怀东 吴贺 +2 位作者 王曦冉 李青 王成飞 《中国电力》 CSCD 北大核心 2014年第11期64-69,共6页
提出了一种适用于变电站大范围监测的局部放电定位算法。该算法基于接收信号指示强度(RSSI),结合传感器数据实际情况补充计算节点。与传统三边加权定位方式不同,引入不定量条定位中垂线与三边区域共同加权。该模型考虑现实情况下放电位... 提出了一种适用于变电站大范围监测的局部放电定位算法。该算法基于接收信号指示强度(RSSI),结合传感器数据实际情况补充计算节点。与传统三边加权定位方式不同,引入不定量条定位中垂线与三边区域共同加权。该模型考虑现实情况下放电位置在高度轴上与传感器群不在一个平面的情况,通过中垂线的引入可以有效地抑制定位误差。实验结果表明,所提出的改进定位模型能有效地匹配现实放电监测硬件,定位误差小于传统三边加权定位,结果符合工程要求。 展开更多
关键词 变电站 局部放电 定位算法 传感器 加权定位 监测 模型 定位误差
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蜂窝无线定位技术的发展及应用 被引量:10
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作者 黎海涛 张平 《电信科学》 北大核心 2001年第9期20-23,共4页
本文首先介绍了移动通信系统中无线定位技术的应用 ,讨论了基于移动台和网络的两种无线定位方案 ,对几类常用的无线定位方法进行了分析 ,分别阐述了GSM和CDMA两种蜂窝系统中无线定位的应用特点 。
关键词 蜂窝系统 无线定位 CDMA GSM 移动通信
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