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Darboux transformation,positon solution,and breather solution of the third-order flow Gerdjikov–Ivanov equation
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作者 Shuzhi Liu Ning-Yi Li +1 位作者 Xiaona Dong Maohua Li 《Chinese Physics B》 2025年第1期195-202,共8页
The third-order flow Gerdjikov–Ivanov(TOFGI)equation is studied,and the Darboux transformation(DT)is used to obtain the determinant expression of the solution of this equation.On this basis,the soliton solution,ratio... The third-order flow Gerdjikov–Ivanov(TOFGI)equation is studied,and the Darboux transformation(DT)is used to obtain the determinant expression of the solution of this equation.On this basis,the soliton solution,rational solution,positon solution,and breather solution of the TOFGI equation are obtained by taking zero seed solution and non-zero seed solution.The exact solutions and dynamic properties of the Gerdjikov–Ivanov(GI)equation and the TOFGI equation are compared in detail under the same conditions,and it is found that there are some differences in the velocities and trajectories of the solutions of the two equations. 展开更多
关键词 third-order flow Gerdjikov-Ivanov equation solitons positons BREATHERS
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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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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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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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Positon and hybrid solutions for the(2+1)-dimensional complex modified Korteweg-de Vries equations
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作者 Feng Yuan Behzad Ghanbari 《Chinese Physics B》 SCIE EI CAS 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 th... 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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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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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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以行动塑造“他者性”立场的教师角色
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作者 周立波 《教育理论与实践》 北大核心 2025年第25期58-64,共7页
随着时代的变迁,教师所扮演的角色在发生着变化。基于主体哲学视角,近代以来,教师角色立场经历了从“唯我论”主体立场到主体间性立场再到“他者性立场”的变化。他者性立场的教师角色的实质是教师秉持他者绝对优先立场,以“为他”的多... 随着时代的变迁,教师所扮演的角色在发生着变化。基于主体哲学视角,近代以来,教师角色立场经历了从“唯我论”主体立场到主体间性立场再到“他者性立场”的变化。他者性立场的教师角色的实质是教师秉持他者绝对优先立场,以“为他”的多元共存的教育主体关系超越基于主体间性的你我关系,以伦理导向的教育关系承担起对受教育者成长的无条件责任。沟通与交往是教育发挥作用的基本方式,这使得教育与行动具有同构性,因此,行动就成为了塑造“他者性”立场的教师角色的途径。教师应以行动具备他者性立场的角色身份,并以行动完成他者性立场的角色塑造。 展开更多
关键词 教师角色 他者性立场 行动理论 主体哲学 主体间性
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一类一阶半正周期边值问题正解的存在性
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作者 王玉芳 《吉林大学学报(理学版)》 北大核心 2025年第5期1239-1246,共8页
考虑一阶半正周期边值问题{-u′(t)+a(t)u(t)=λf(t,u(t)),t∈(0,T),u(0)=u(T)正解的存在性,其中λ为正参数,a∈C([0,T],R),f∈C([0,T]×[0,∞),R),f(t,0)<0且lim_(u→∞)f(t,u)/u=∞.基于Krasnoselskill不动点定理,证明存在λ*&... 考虑一阶半正周期边值问题{-u′(t)+a(t)u(t)=λf(t,u(t)),t∈(0,T),u(0)=u(T)正解的存在性,其中λ为正参数,a∈C([0,T],R),f∈C([0,T]×[0,∞),R),f(t,0)<0且lim_(u→∞)f(t,u)/u=∞.基于Krasnoselskill不动点定理,证明存在λ*>0,使得当0<λ<λ*时,该问题至少有一个解. 展开更多
关键词 周期边值问题 半正 不定权 正解 Krasnoselskill不动点定理
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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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煤矿井下精确定位技术的应用探讨
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作者 汪洋 《科技资讯》 2025年第2期195-197,共3页
随着科技的飞速发展,煤矿行业正逐步迈入智能化、数字化的新时代。在智能矿山建设的进程中,煤矿井下精确定位技术凭借其重要性和实用性成为推动煤矿安全生产的重要力量。井下精确定位可以按照工作机制分为通信式定位和惯导定位,二者都... 随着科技的飞速发展,煤矿行业正逐步迈入智能化、数字化的新时代。在智能矿山建设的进程中,煤矿井下精确定位技术凭借其重要性和实用性成为推动煤矿安全生产的重要力量。井下精确定位可以按照工作机制分为通信式定位和惯导定位,二者都可以对井下复杂巷道中人、车等进行精确定位,并对人员状态、车辆使用等进行分析,以此来满足煤矿井下作业的需求。基于此,对煤矿井下精确定位技术现状及应用进行研究,以期为相关部门提供参考。 展开更多
关键词 井下精确定位 通信式定位 UWB定位技术 煤矿井下作业
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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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一类半正二阶Dirichlet边值问题正解的存在性
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作者 李存丽 《山东大学学报(理学版)》 CSCD 北大核心 2024年第12期96-101,121,共7页
考察二阶半正问题{-u″(t)=λ(f(u(t))+a(t)),t∈(0,1),u(0)=u(1)=0正解的存在性,其中λ是正参数,a∈C([0,1],R),f∈C([0,∞),[0,∞))。f满足超线性增长条件时,证得存在常数λ>0,当0<λ<λ*时,问题存在一个正解。主要结果的证... 考察二阶半正问题{-u″(t)=λ(f(u(t))+a(t)),t∈(0,1),u(0)=u(1)=0正解的存在性,其中λ是正参数,a∈C([0,1],R),f∈C([0,∞),[0,∞))。f满足超线性增长条件时,证得存在常数λ>0,当0<λ<λ*时,问题存在一个正解。主要结果的证明基于锥上的不动点定理。 展开更多
关键词 正解 半正问题 DIRICHLET边界条件 不动点定理
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基于被动柔顺的机器人抛磨力/位混合控制方法 被引量:43
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作者 黄婷 孙立宁 +2 位作者 王振华 禹鑫燚 陈国栋 《机器人》 EI CSCD 北大核心 2017年第6期776-785,794,共11页
为了实现抛磨系统机器人末端的位置控制和接触力控制,提出一种基于被动柔顺装置的机器人抛磨系统力/位混合控制策略.在机器人末端安装一个柔顺装置实现对工具末端力控制和位置控制的解耦.柔顺装置一端安装于机器人末端,另一端连接抛磨工... 为了实现抛磨系统机器人末端的位置控制和接触力控制,提出一种基于被动柔顺装置的机器人抛磨系统力/位混合控制策略.在机器人末端安装一个柔顺装置实现对工具末端力控制和位置控制的解耦.柔顺装置一端安装于机器人末端,另一端连接抛磨工具.机器人控制器控制机器人末端位姿,间接对工具末端位姿进行控制和补偿,柔顺装置控制器直接控制工具与工件的接触力.经过建模分析,采用非线性PD(比例-微分)控制提高了柔顺装置的动态调节性能.仿真结果证明该方法可以对目标轨迹进行跟踪与补偿,并实现期望力的快速调节.非线性PD控制将柔顺装置受干扰后恢复稳定的调节时间由220 ms提高到60 ms.实验进一步验证了仿真结果,并通过对航空叶片进行打磨与抛光获得了良好的表面质量.结果表明提出的控制方法是切实可行的. 展开更多
关键词 机器人抛磨 被动柔顺 力/位混合控制 位姿补偿 非线性PD控制
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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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