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电子商务模式模仿者与创新者竞争动态研究——当当网和亚马逊中国竞争演变分析 被引量:24
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作者 王砚羽 谢伟 《科学学与科学技术管理》 CSSCI 北大核心 2013年第6期44-51,共8页
利用竞争扩散模型Lotka-Volterra分析了我国书籍网购市场中当当网和亚马逊中国这两个主要竞争者的市场竞争动态。从模型的分析效果来看,Lotka-Volterra模型在分析竞争性市场中更具有适用性,并且比Logistic模型具有更好的拟合度;从分析... 利用竞争扩散模型Lotka-Volterra分析了我国书籍网购市场中当当网和亚马逊中国这两个主要竞争者的市场竞争动态。从模型的分析效果来看,Lotka-Volterra模型在分析竞争性市场中更具有适用性,并且比Logistic模型具有更好的拟合度;从分析结果来看,当当网在独占性市场的发展动力大于亚马逊中国,同时当当网在模仿创新过程中获得了一定的收益;但当当网和亚马逊中国的竞争关系为被捕食者—捕食者关系,并且当当网的进攻优势只是亚马逊中国反击能力的一半;当当网和亚马逊中国在近几年中将不会出现平衡点,两者差距将逐渐增大。 展开更多
关键词 lotka-volterra 当当网 亚马逊中国 商业模式创新
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Periodicity and Stability in Periodic n-Species Lotka-Volterra Competition System with Feedback Controls and Deviating Arguments 被引量:17
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作者 MengFAN KeWANG +1 位作者 PatriciaJ.Y.WONG RaviP.AGARWAL 《Acta Mathematica Sinica,English Series》 SCIE CSCD 2003年第4期801-822,共22页
By using the method of coincidence degree and Lyapunov functional, a set ofeasily applicable criteria are established for the global existence and global asymptotic stabilityof strictly positive (componentwise) period... By using the method of coincidence degree and Lyapunov functional, a set ofeasily applicable criteria are established for the global existence and global asymptotic stabilityof strictly positive (componentwise) periodic solution of a periodic n-species Lotka-Volterracompetition system with feedback controls and several deviating arguments. The problem considered inthis paper is in many aspects more general and incorporate as special cases various problems whichhave been studied extensively in the literature. Moreover, our new criteria, which improve andgeneralize some well known results, can be easily checked. 展开更多
关键词 strictly positive periodic solutions globally asymptotic stability lotka-volterra competition system feedback controls deviating arguments coincidence degree Lyapunov functional
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New exact solutions to some difference differential equations 被引量:15
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作者 王振 张鸿庆 《Chinese Physics B》 SCIE EI CAS CSCD 2006年第10期2210-2215,共6页
In this paper, we use our method to solve the extended Lotka-Volterra equation and discrete KdV equation. With the help of Maple, we obtain a number of exact solutions to the two equations including soliton solutions ... In this paper, we use our method to solve the extended Lotka-Volterra equation and discrete KdV equation. With the help of Maple, we obtain a number of exact solutions to the two equations including soliton solutions presented by hyperbolic functions of sinh and cosh, periodic solutions presented by trigonometric functions of sin and cos, and rational solutions. This method can be used to solve some other nonlinear difference-differential equations. 展开更多
关键词 difference differential equation soliton solutions lotka-volterra equation discrete KdV equation
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GLOBAL ASYMPTOTIC STABILITY IN N-SPECIES NONAUTONOMOUS LOTKA-VOLTERRACOMPETITIVE SYSTEMS WITH DELAYS 被引量:12
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作者 徐瑞 陈兰荪 M.A.J.Chaplain 《Acta Mathematica Scientia》 SCIE CSCD 2003年第2期208-218,共11页
A delayed n-species nonautonomous Lotka-Volterra type competitive system without dominating instantaneous negative feedback is investigated. By means of a suitable Lyapunov functional, sufficient conditions are derive... A delayed n-species nonautonomous Lotka-Volterra type competitive system without dominating instantaneous negative feedback is investigated. By means of a suitable Lyapunov functional, sufficient conditions are derived for the global asymptotic stability of the positive solutions of the system. As a corollary, it is shown that the global asymptotic stability of the positive solution is maintained provided that the delayed negative feedbacks dominate other interspecific interaction effects with delays and the delays are sufficiently small. 展开更多
关键词 Nonautonomous lotka-volterra competitive system finite and infinite delay global asymptotic stability Lyapunov functional
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THE EFFECTS OF TIMING OF PULSE SPRAYING AND RELEASING PERIODS ON DYNAMICS OF GENERALIZED PREDATOR-PREY MODEL 被引量:13
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作者 CHANGTONG LI SANYI TANG 《International Journal of Biomathematics》 2012年第1期157-183,共27页
Based on the facts of releasing natural enemies and spraying pesticides at different time points, we propose a generalized predator-prey model with impulsive interventions. The threshold values for the existence and s... Based on the facts of releasing natural enemies and spraying pesticides at different time points, we propose a generalized predator-prey model with impulsive interventions. The threshold values for the existence and stability of pest eradication periodic solution are provided under the assumptions of releasing natural enemies either more or less frequent than spray. In order to address how the different pulse time points, control tactics affect the pest control (i.e. the threshold value), the Holling Type II Lotka-Volterra predator- prey system, as an example, with impulsive intervention at different time points axe investigated carefully. The numerical results show how the threshold values are affected by the factors including instantaneous killing rates of pesticides on pests and natural enemies, the release rate of natural enemies and release constant, timing of pesticide application and timing of release period. Furthermore, it is confirmed that the system has the coexistences of pests and natural enemies for a wide range of parameters and with quite different pest amplitudes. 展开更多
关键词 Predator-prey model PULSE integrated pest management threshold value Holling II function response.
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Existence of Positive Periodic Solutions of Competitor-Competitor-Mutualist Lotka-Volterra Systems with Infinite Delays 被引量:9
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作者 ZHANG Daoxiang DING Weiwei ZHU Min 《Journal of Systems Science & Complexity》 SCIE EI CSCD 2015年第2期316-326,共11页
In this paper,the authors primarily explore a delayed competitor-competitor-mutualist Lotka-Volterra model,which is a system of differential equation with infinite integral.The authors first study the existence of pos... In this paper,the authors primarily explore a delayed competitor-competitor-mutualist Lotka-Volterra model,which is a system of differential equation with infinite integral.The authors first study the existence of positive periodic solutions of the model by using the Krasnoselskii's fixed point theorem,and then present an example to illustrate the main results. 展开更多
关键词 Competitor-competitor-mutualist lotka-volterra systems with infinite delays Krasnoselskii's fixed point theorem positive periodic solutions.
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高技术服务创新网络生态位重叠企业竞合关系建模与仿真 被引量:10
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作者 孙耀吾 韩冰 黄万艮 《科技进步与对策》 CSSCI 北大核心 2014年第13期59-63,共5页
在高技术服务创新网络中,参与主体生态位重叠与竞合关系复杂。应用生态位理论中Lotka-Volterra原理,构建企业生态位演化模型群,并进行系统仿真,揭示不同类型高技术服务创新网络参与主体的动态竞合关系。研究结果表明,生态位重叠的创新... 在高技术服务创新网络中,参与主体生态位重叠与竞合关系复杂。应用生态位理论中Lotka-Volterra原理,构建企业生态位演化模型群,并进行系统仿真,揭示不同类型高技术服务创新网络参与主体的动态竞合关系。研究结果表明,生态位重叠的创新主体间只有采取合作共生模式,才会产生企业生态位协同进化;片面追求自身发展的单向思维模式,反而可能导致企业生态位被逐渐侵蚀。该研究结论对于探索科学治理创新网络、促进企业协同发展具有重要启示。 展开更多
关键词 高技术服务创新网络 生态位重叠 lotka-volterra 模型 竞合关系
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Road Resources Distribution and Evolution Analysis Using a Species Competition Model for Improving Road Equity 被引量:8
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作者 应习文 石京 《Tsinghua Science and Technology》 SCIE EI CAS 2008年第5期651-659,共9页
The paper analyzes the equity of road resources distribution in urban areas by modeling the competitive relationship among different road users. A logistic model is used to describe the development of different traffi... The paper analyzes the equity of road resources distribution in urban areas by modeling the competitive relationship among different road users. A logistic model is used to describe the development of different traffic modes in the transportation network. The system is similar to the species competition model, so a two-species model is used to analyze the relationship between users based on the stability of the equilibrium points. The Lotka-Volterra model is then used to describe the multi-species cases with numerical examples, showing that this model can describe the effects of the road space distribution on the competitive user relationships. Policy makers must ensure the equity of road resources distribution so that each urban transportation mode is properly developed for sustainable social development. 展开更多
关键词 EQUITY competition model resource distribution lotka-volterra model
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Positive Solutions Bifurcating from Zero Solution in a Lotka-Volterra Competitive System with Cross-Diffusion Effects 被引量:8
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作者 ZHANG Cun-hua YAN Xiang-ping 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2011年第3期342-352,共11页
A strongly coupled elliptic system under the homogeneous Dirichlet boundary condition denoting the steady-state system of the Lotka-Volterra two-species competitive system with cross-diffusion effects is considered. B... A strongly coupled elliptic system under the homogeneous Dirichlet boundary condition denoting the steady-state system of the Lotka-Volterra two-species competitive system with cross-diffusion effects is considered. By using the implicit function theorem and the Lyapunov- Schmidt reduction method, the existence of the positive solutions bifurcating from the trivial solution is obtained. Furthermore, the stability of the bifurcating positive solutions is also investigated by analyzing the associated characteristic equation. 展开更多
关键词 lotka-volterra competitive system CROSS-DIFFUSION Positive solution Steady state bifurcation Stability.
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基于Lotka-Volterra的高技术虚拟产业集群成员间合作与竞争模型 被引量:8
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作者 高长元 杜鹏 《科技进步与对策》 CSSCI 北大核心 2009年第23期72-75,共4页
高技术虚拟产业集群是知识经济时代的一种新型集群模式,集群成员间合作与竞争是集群演化的动力,探寻集群成员间合作与竞争活动的规律,对集群发展具有重要的作用。在对高技术虚拟产业集群成员间合作与竞争活动分析的基础上,基于Lotka-Vol... 高技术虚拟产业集群是知识经济时代的一种新型集群模式,集群成员间合作与竞争是集群演化的动力,探寻集群成员间合作与竞争活动的规律,对集群发展具有重要的作用。在对高技术虚拟产业集群成员间合作与竞争活动分析的基础上,基于Lotka-Volterra模型的思想,建立了高技术虚拟产业集群成员间合作与竞争模型,并对模型进行了分析与扩展。 展开更多
关键词 高技术虚拟产业集群 合作 竞争 lotka-volterra
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共生理论视域下区域智库联盟演进路径与发展机制研究 被引量:1
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作者 朱婧祎 李北伟 +1 位作者 李瑞 李麟白 《智库理论与实践》 CSSCI 北大核心 2024年第4期66-78,共13页
[目的/意义]区域智库联盟是中国特色新型智库建设的重要载体。本文结合共生理论探讨区域智库联盟演进路径和发展机制,以期拓展智库联盟相关研究,为区域智库联盟稳定发展提供有益参考。[方法/过程]首先,在明晰区域智库联盟共生系统要素... [目的/意义]区域智库联盟是中国特色新型智库建设的重要载体。本文结合共生理论探讨区域智库联盟演进路径和发展机制,以期拓展智库联盟相关研究,为区域智库联盟稳定发展提供有益参考。[方法/过程]首先,在明晰区域智库联盟共生系统要素构成的基础上,从共生组织模式和共生行为模式两个方向分析区域智库联盟演进路径;然后,构建基于Lotka-Volterra方程的区域智库联盟共生演化模型,并通过模型的稳定性条件分析和模拟仿真讨论不同共生行为模式下联盟成员相互作用的演化规律以及平衡状态;最后,提出区域智库联盟共生发展机制。[结果/结论]基于质参量兼容原理、共生能量生成原理、共生系统进化原理和共生系统相变原理,区域智库联盟共生发展机制包括环境引导机制、界面增容机制、能量协调机制和新陈代谢机制。 展开更多
关键词 区域智库联盟 共生理论 lotka-volterra 模型 仿真
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Positive solutions for a Lotka-Volterra prey-predator model with cross-diffusion and Holling type-Ⅱ functional response 被引量:6
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作者 ZHOU Jun KIM Chan-Gyun 《Science China Mathematics》 SCIE 2014年第5期991-1010,共20页
We consider a Lotka-Volterra prey-predator model with cross-diffusion and Holling type-II functional response.The main concern is the existence of positive solutions under the combined effect of cross-diffusion and Ho... We consider a Lotka-Volterra prey-predator model with cross-diffusion and Holling type-II functional response.The main concern is the existence of positive solutions under the combined effect of cross-diffusion and Holling type-II functional response.Here,a positive solution corresponds to a coexistence state of the model.Firstly,we study the sufficient conditions to ensure the existence of positive solutions by using degree theory and analyze the coexistence region in parameter plane.In addition,we present the uniqueness of positive solutions in one dimension case.Secondly,we study the stability of the trivial and semi-trivial solutions by analyzing the principal eigenvalue of the corresponding linearized system,and then we characterize the stable/unstable regions of semi-trivial solutions in parameter plane. 展开更多
关键词 lotka-volterra prey-predator model Holling type-II functional response CROSS-DIFFUSION positive solutions coexistence UNIQUENESS degree theory
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非自治Lotka-Volterra两种群合作系统的持久性 被引量:7
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作者 吴亭 《科技通报》 北大核心 2009年第6期743-746,共4页
通过发展Yukihiko Nakata和Yoshiaki Muroya的分析手法,研究一类时滞是任意常数的非自治Lotka-Volterra两种群合作系统持久性,从而推广了文的主要结果.
关键词 合作系统 时滞 种群 持久性
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具有毒素影响的非简化二维Lotka-Volterra模型 被引量:6
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作者 闫慧臻 《大连轻工业学院学报》 1995年第1期54-59,共6页
本文研究了具有毒素影响的非简化二维Volterra模型,给出了两种群持续生存与绝灭的一些充分条件,从而为实际应用提供了一定的理论依据。
关键词 种群 持续生存 绝灭 lotka-volterra 模型 毒素
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四川缙云山森林群落演替机理初探 被引量:5
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作者 熊利民 钟章成 《西南师范大学学报(自然科学版)》 CAS CSCD 1991年第1期89-95,共7页
据根对缙云山森林群落中优势种生长量的多元线性回归分析,发现有的种间线性相关显著,有的不显著.对线性相关显著的优势种,进一步应用Lotka-Volterra竞争模型进行了预测,预测结果同其它方法预测结果及实地调查结果基本一致.分析说明了在... 据根对缙云山森林群落中优势种生长量的多元线性回归分析,发现有的种间线性相关显著,有的不显著.对线性相关显著的优势种,进一步应用Lotka-Volterra竞争模型进行了预测,预测结果同其它方法预测结果及实地调查结果基本一致.分析说明了在这些线性相关显著的种间,种间竞争是演替的主要动力;而那些线性相关不显著的种间,其它因子才是演替的主要动力. 展开更多
关键词 森林群落 演替机理 L-V竞争模型
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THE STRUCTURE OF LASALLE’S INVARIANT SET FOR LOTKA-VOLTERRA SYSTEMS 被引量:4
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作者 刘立 陆征一 王东明 《Science China Mathematics》 SCIE 1991年第7期783-790,共8页
<正> By developing the mechanical proving method, we determine the structure of LaSalle’sinvariant set for 7-dimensional Lotka-Volterra food chain systems, based on Ritt-Wu’s prin-ciple. We then further show t... <正> By developing the mechanical proving method, we determine the structure of LaSalle’sinvariant set for 7-dimensional Lotka-Volterra food chain systems, based on Ritt-Wu’s prin-ciple. We then further show that the locally asymptotical stable equilibrium point of Lotka-Volterra food chain systems for 7 dimension must be globally stable. 展开更多
关键词 lotka-volterra systems LaSalle’s INVARIANT set well-ordering PRINCIPLE global stability.
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Dynamics of dominant tree species in a forest ecotone on the northern slop of Changbai Mountain 被引量:4
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作者 YU Da-pao ZHAI Lian-jiang +1 位作者 WANG Qing-li DAI Li-min 《Journal of Forestry Research》 SCIE CAS CSCD 2006年第3期216-220,共5页
The competition and dynamics of dominant trees species in the forest ecotone between the broad-leaved/Korean pine (Pinus koraiensis) mixed forest and the spruce-fir forest (also known as dark conifer forest) in Ch... The competition and dynamics of dominant trees species in the forest ecotone between the broad-leaved/Korean pine (Pinus koraiensis) mixed forest and the spruce-fir forest (also known as dark conifer forest) in Changbai Mountain, Jilin Province in Northeast China were studied by using Lotka-Volterra model, based on the data from twenty-eight sample plots with area of 20 mx90 m for each one. Results showed that under natural condition, differentiation of communities followed two directions: one would be Spruce (Picea jezoensis and few P. koraiensis) and fir (Abies nephrolepis) co-dominant conifer forest, and at the equilibrium fir was absolutely preponderant (77.1% of relative dominance (RD)); the other would be the conifer and broad-leaved mixed forest, and at equilibrium, the broad-leaved tree species was 50% of RD in the broad-leaved/Korean pine mixed forest and 66% of RD in the broad-leaved and spruce-fir mixed forest. The study demonstrated that both broad-leaved/Korean pine mixed forest and dark conifer forest were climax community, the ecotone had transitional characteristics, and the diversification of the forest communities suggested that the direction of succession was affected by local habitat. 展开更多
关键词 Competition and dynamics lotka-volterra model Forest ecotone Changbai Mountain
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一类具时滞的中立型Lotka-Volterra模型的周期解(英文) 被引量:3
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作者 李必文 程舰 《数学杂志》 CSCD 北大核心 2004年第2期221-225,共5页
讨论了n种群时滞的中立型Lotka Volterra生态模型。利用新的重合度理论中连续性定理 。
关键词 周期解 中立型 lotka-volterra
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Propagation Dynamics of Forced Pulsating Waves for a Time Periodic Lotka-Volterra Cooperative System with Nonlocal Effects in Shifting Habitats
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作者 Zewen Gong 《Journal of Applied Mathematics and Physics》 2024年第10期3402-3421,共20页
In this paper, we will concern the existence, asymptotic behaviors and stability of forced pulsating waves for a Lotka-Volterra cooperative system with nonlocal effects under shifting habitats. By using the alternativ... In this paper, we will concern the existence, asymptotic behaviors and stability of forced pulsating waves for a Lotka-Volterra cooperative system with nonlocal effects under shifting habitats. By using the alternatively-coupling upper-lower solution method, we establish the existence of forced pulsating waves, as long as the shifting speed falls in a finite interval where the endpoints are obtained from KPP-Fisher speeds. The asymptotic behaviors of the forced pulsating waves are derived. Finally, with proper initial, the stability of the forced pulsating waves is studied by the squeezing technique based on the comparison principle. 展开更多
关键词 Nonlocal Effects Time Periodic lotka-volterra System Forced Pulsating Waves Shifting Habitats
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离散型时滞Lotka-Volterra食饵-捕食者系统的8个正周期解 被引量:3
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作者 吕小俊 李睿 《西南大学学报(自然科学版)》 CAS CSCD 北大核心 2020年第7期114-123,共10页
采取叠合度的Mawhin连续定理和微分不等式,研究带有收获项的离散型Lotka-Volterra食饵-捕食者系统,并获得该系统存在8个正周期解的充分条件.
关键词 离散型 lotka-volterra 食饵-捕食者系统 8个正周期解 收获项
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