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Study on coopetition relationship simulation among M-commerce information service subjects based on lotka-volterra model

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Journal of Management Analytics 2023年第3期10卷 583-606页

作者： Xiaojun Xu Linzhong Xu Xiaoli Wang School of Economics and Management Yanshan UniversityQinhuangdaoPeople’s Republic of China

In order to explore the evolution law of coopetition relationship among Mcommerce information service(MIS)subjects and further reveal the allocation mechanism of information resources,the research extends lotka-volterra model,builds the coopetition relationship model of MIS subjects and simulates their coopetition relationship by Python and MATLAB to obtain the evolution trend of information resources possession(IRP)of MIS subjects in the coopetition *** results show that the mutualism cooperation pattern dominated by promoting effect can maximize the value of information *** paper has significant reference value for how to optimize the allocation of information resources among MIS subjects.

关键词： coopetition relationship M-commerce information service information resources possession stable equilibrium state simulation lotka-volterra model

Road Resources Distribution and Evolution Analysis Using a Species Competition model for Improving Road Equity

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Tsinghua Science and Technology 2008年第5期13卷 651-659页

作者：应习文石京 Institute of Transportation Engineering Department of Civil EngineeringTsinghua University

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.

关键词： equity competition model resource distribution lotka-volterra model

Bifurcations and chaos control in a discrete-time biological model

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International Journal of Biomathematics 2020年第4期13卷 1-31页

作者： A.Q.Khan T.Khalique Department of Mathematics University of Azad Jammu and Kashmir Muzaffarabad 13100 Pakistan

In this papcr,bifurcations and chaos control in a discrete-time lotka-volterra predator-prey model have been studied in *** is shown that for all parametric values,model hus boundary equilibria:P00(0,0),Px0(1,0),and the unique positive equilibrium point:P^+xy(d/c,r(c-d)/bc) if c>*** Linearization method,we explored the local dynamics along with different topological classifications about *** also explored the boundedness of positive solution,global dynamics,and existence of prime-period and periodic points of the *** is explored that flip bifurcation occurs about boundary equilibria:Poo(0,0),P.o(1,0),and also there exists a flip bifurcation when parameters of the discrete-time model vary in a small neighborhood of P^+xy(d/c,r(c-d)/bc).Further,it is also explored that about P^+xy(d/c,r(c-d)/bc) the model undergoes a N-S bifurcation,and meanwhile a stable close invariant curves *** the perspective of biology,these curves imply that betwecn predator and prey populations,there exist periodic or quasi-periodic *** simulations are presented to illustrate not only main results but also reveals the complex dynamics such as the orbits of period-2,3,13,15,17 and *** Maximum Lyapunov exponents as well as fractal dimension are computed numeri-cally to justify the chaotic behaviors in the ***,feedback control method is applied to stabilize chaos existing in the model.

关键词： lotka-volterra model bifurcations and chaos center manifold theorem numerical simulation

Variability of Prorocentrum donghaiense response to allelopathic action from Alexandrium pacificum in laboratory culture

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Journal of Oceanology and Limnology 2021年第4期39卷 1305-1315页

作者： Hongjia HUANG Chuqiao GAN Jiahui HUANG Chen ZOU Hongye LI Jiesheng LIU Weidong YANG Key Laboratory of Aquatic Eutrophication and Control of Harmful Algal Blooms of Guangdong Higher Education Institute College of Life Science and TechnologyJinan UniversityGuangzhou 510632China

The dinoflagellates Alexandrium pacificum and Prorocentrum donghaiense are two well-known harmful algal blooms(HABs)-forming species,both were usually found in the same sea areas in form of HABs in *** date,there is no mechanistic model that can fully explain the occurrence of *** blooms with *** found that different strains of *** had different intrinsic growth rates of 0.107-0.215/d,and these strains exhibited different responses to the allelopathic action from *** strains of *** could grow well despite some degrees of inhibition in a short period,suggesting the two algal species *** and *** could coexist,even if *** was *** findings may advance the understanding of phenotypes in *** and provide a potential mechanism involved in the coexistence of *** and *** in the same area.

关键词： Prorocentrum donghaiense allelopathy lotka-volterra model algal bloom phenotype

Interspecific Competition Between Levanderina fissa(Dinophyceae) and the Other Three Microalgal Species in Co-Cultures

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Journal of Ocean University of China 2019年第4期18卷 919-925页

作者： WANG Zhaohui ZHAO Jianggang XIAO Lin LIN Langcong College of Life Science and Technology Key Laboratory of Eutrophication and Red Tide Prevention of Guangdong Higher Education Institutes Jinan University

Growth interactions between the dinoflagellate Levanderina fissa (=Gyrodinium instriatum) and the other three algal bloom species Skeletonema costatum (Bacillariophyceae), Prorocentrum micans (Dinophyceae), and Chattonella marina (Raphido- phyceae) were studied using bi- or tri-algal co-cultures under laboratory conditions. The lotka-volterra model was applied to esti- mate the interspecific competition between them. Results showed that the growth of L. fissa was significantly suppressed in both bi-algal and tri-algal cultures, and the maximum cell densities in co-cultures were only between 21% and 69% of that in mono-cul- ture. L. fissa outcompeted P. micans;however, its effects on S. costatum and C. marina were generally less than the effects of their intraspecific competitions based on the competition coefficients. Contrarily, the inhibitory effects of S. costatum and C. marina on L. fissa were much greater. S. costatum outcompeted the other three species in all co-cultures, and its competition coefficients on the other species were more than 10000 times higher than the opposite. The growth of C. marina was suppressed by S. costatum;how- ever, it outcompeted L. fissa and P. micans. The growth of P. micans was most strongly inhibited in co-cultures, and the maximum cell densities in co-cultures were less than 15% of that in mono-species culture. The results suggested that L. fissa had few advan- tages in the interspecific competition. The adaptation to low salinity and the utilization of organic phosphorus might be the important reasons for L. fissa to take the competitive predominance in brackish estuarine environments.

关键词： growth interaction interspecific competition lotka-volterra model Levanderina fissa Gyrodinium instriatum Skeletonema costatum Prorocentrum mican Chattonella marina

Homotopy perturbation aided optimization procedure with applications to oscillatory fractional order nonlinear dynamical systems

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International Journal of modeling, Simulation, and Scientific Computing 2019年第4期10卷 107-128页

作者： Najeeb Alam Khan Tooba Hameed Samreen Ahmed Department of Mathematics University of KarachiKarachi 75270Pakistan

This paper presents an approximate solution of nonlinear fractional differential equations(FDEs)that exhibit an oscillatory behavior by using a metaheuristic *** solutions of the governing equations are approximated by using homotopy perturbation method(HPM)along with the fractional derivative in the Caputo *** designed methodology is based on a weighted series of HPM in conjunction with a nature-inspired *** idea is instantly fascinated by the researchers on the consequent implementation of nature-inspired learning algorithms such as a Cuckoo search algorithm(CSA).The usage of CSA has accelerated the minimized search path of error to the convergent values of the *** validity and accuracy of the proposed technique are ascertained by calculating the approximate solution and the error norms which ensure the convergence of the approximation that can be further *** critical analysis is also provided by the numerical simulation of two different test *** of key points has been determined by the tabulation of numerical values and *** study of the results with known numerical technique is also performed.

关键词： lotka-volterra model Brusselator model Caputo fractional derivative Cuckoo search algorithm

Hybrid competitive lotka–volterra ecosystems with a hidden Markov chain

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Journal of Control and Decision 2014年第1期1卷 51-74页

作者： Ky Tran George Yin Department of Mathematics Wayne State UniversityDetroitMIUSA

This work concerns lotka–volterra models that are formulated using stochastic differential equations with *** from the existing formulations,the Markov chain that models random environments is *** such partially observed systems,we use Wonham’s filter to estimate the Markov chain from the observable evolution of the population,and convert the original system to a completely observable *** then show that the positive solution of our model does not explode in finite time with probability *** properties including stochastic boundedness,finite moments,sample path continuity and large-time asymptotic behaviour are also ***,stochastic permanence,extinction and feedback controls are also investigated.

关键词： lotka-volterra model hidden Markov chain partially observed system

Dynamics of dominant tree species in a forest ecotone on the northern slop of Changbai Mountain

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Journal of Forestry Research 2006年第3期17卷 216-220页

作者： YU Da-pao ZHAI Lian-jiang WANG Qing-li DAI Li-min Institute of Apphed Ecology Chinese Academy of Sciences Shenyang 110016 P. R. China Forestry Department of Liaonmg Province Shenyang 110014 P. R. China Shenyang Branch Chinese Academy of Sciences Shenyang 110005 P. R. China.

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.

关键词： Competition and dynamics lotka-volterra model Forest ecotone Changbai Mountain