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ENTIRE SOLUTIONS OF LOTKA-VOLTERRA COMPETITION SYSTEMS WITH NONLOCAL DISPERSAL
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作者 郝玉霞 李万同 +1 位作者 王佳兵 许文兵 《Acta Mathematica Scientia》 SCIE CSCD 2023年第6期2347-2376,共30页
This paper is mainly concerned with entire solutions of the following two-species Lotka-Volterra competition system with nonlocal(convolution)dispersals:{u_(t)=k*u-u+u(1-u-av),x∈R,t∈R,vt=d(k*v-v)+rv(1-v-bu),c∈R,t∈... This paper is mainly concerned with entire solutions of the following two-species Lotka-Volterra competition system with nonlocal(convolution)dispersals:{u_(t)=k*u-u+u(1-u-av),x∈R,t∈R,vt=d(k*v-v)+rv(1-v-bu),c∈R,t∈R.(0.1)Here a≠1,b≠1,d,and r are positive constants.By studying the eigenvalue problem of(0.1)linearized at(ϕc(ξ),0),we construct a pair of super-and sub-solutions for(0.1),and then establish the existence of entire solutions originating from(ϕc(ξ),0)as t→−∞,whereϕc denotes the traveling wave solution of the nonlocal Fisher-KPP equation ut=k*u−u+u(1−u).Moreover,we give a detailed description on the long-time behavior of such entire solutions as t→∞.Compared to the known works on the Lotka-Volterra competition system with classical diffusions,this paper overcomes many difficulties due to the appearance of nonlocal dispersal operators. 展开更多
关键词 entire solutions Lotka-Volterra competition systems nonlocal dispersal traveling waves
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Research on the Development of School Football Competition System for Youth in Chongqing
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作者 Yun Liu Yiming Yang Xia Wang 《Journal of Contemporary Educational Research》 2020年第9期51-55,共5页
This study analyzes the current situation and problems of the school football competition system in Chongqing through literature search,interviews,and questionnaires.With this,a development model suitable for the esta... This study analyzes the current situation and problems of the school football competition system in Chongqing through literature search,interviews,and questionnaires.With this,a development model suitable for the establishment of a school football system for young people is proposed.Besides,this study aims to promote the construction and improvement and boost the competitiveness of school football competition system. 展开更多
关键词 YOUTH School football competition system
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Entropy description of a cooperation-competition system
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作者 徐秀莲 傅春花 +1 位作者 刘春平 何大韧 《Chinese Physics B》 SCIE EI CAS CSCD 2010年第6期1-6,共6页
Understanding the cooperation-competition dynamics is a long-standing challenge in studying complex systems.Inspired by the idea of Shannon entropy,we define competition information entropy and propose an entropy evol... Understanding the cooperation-competition dynamics is a long-standing challenge in studying complex systems.Inspired by the idea of Shannon entropy,we define competition information entropy and propose an entropy evolution model.The analytic results of the model of the relation between competition gain distribution parameters and entropy,as well as the relation between entropy and time are compared with empirical results obtained in 14 real world systems.They are found to be in good agreement with each other. 展开更多
关键词 cooperation-competition ENTROPY competition gain evolution model
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EXISTENCE OF POSITIVE SOLUTION FOR A TWO-PATCHES COMPETITION SYSTEM WITH DIFFUSION AND TIME DELAY AND FUNCTIONAL RESPONSE 被引量:12
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作者 LiBiwen ZengXianwu 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2003年第1期1-8,共8页
By using the continuation theorem of coincidence theory, the existence of a positive periodic solution for a two patches competition system with diffusion and time delay and functional responsex [FK(W1*3/4。*2/3]... By using the continuation theorem of coincidence theory, the existence of a positive periodic solution for a two patches competition system with diffusion and time delay and functional responsex [FK(W1*3/4。*2/3]′ 1 (t)=x 1(t)a 1(t)-b 1(t)x 1(t)-c 1(t)y(t)1+m(t)x 1(t)+D 1(t)[x 2(t)-x 1(t)], x [FK(W1*3/4。*2/3]′ 2 (t)=x 2(t)a 2(t)-b 2(t)x 2(t)-c 2(t)∫ 0 -τ k(s)x 2(t+s) d s+D 2(t)[x 1(t)-x 2(t)], y′(t)=y(t)a 3(t)-b 3(t)y(t)-c 3(t)x 1(t)1+m(t)x 1(t)is established, where a i(t),b i(t),c i(t)(i=1,2,3),m(t) and D i(t)(i=1,2) are all positive periodic continuous functions with period w >0, τ is a nonnegative constant and k(s) is a continuous nonnegative function on [- τ ,0]. 展开更多
关键词 开拓定理 叠和理论 存在性 正周期解 两斑块扩散时滞竞争系统 功能反应 人口动态
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Information Entropy Squeezing for a Atom in Mode-Mode Competition System 被引量:2
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作者 WU Qin FANG Mao-Fa +2 位作者 LI Shao-Xin LI Ying HU Yao-Hua 《Communications in Theoretical Physics》 SCIE CAS CSCD 2008年第12期1411-1416,共6页
The entropy squeezing properties for a two-level atom interacting with a two-mode field via two differentcompeting transitions are investigated from a quantum information point of view.The influences of the initial st... The entropy squeezing properties for a two-level atom interacting with a two-mode field via two differentcompeting transitions are investigated from a quantum information point of view.The influences of the initial state of thesystem and the relative coupling strength between the atom and the field on the atomic information entropy squeezingare discussed.Our results show that the squeezed direction and the frequency of the information entropy squeezing canbe controlled by choosing the phase of the atom dipole and the relative competing strength of atom-field,respectively.We find that,under the same condition,no atomic variance squeezing is predicted from the HUR while optimal entropysqueezing is obtained from the EUR,so the quantum information entropy is a remarkable precision measure for theatomic squeezing in the considered system. 展开更多
关键词 J-C模型 非线性 动力学性质 原子物理学
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Global Asymptotically Stable of a Generalized Discrete Ricker Competition System
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作者 Yoshihiro Hamaya 《Journal of Mathematics and System Science》 2013年第6期282-288,共7页
关键词 全局渐近稳定 广义离散 赛制 充分条件 竞争排斥 平衡点 物种 灭绝
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Quantum entanglement in the mode-mode competition system
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作者 吴琴 方卯发 +1 位作者 冯永振 胡要花 《Chinese Physics B》 SCIE EI CAS CSCD 2008年第8期2963-2968,共6页
Considering a two-level atom interacting with the competing two-mode field, this paper investigates the entangle- ment between the two-level atom and the two-mode field by using the quantum reduced entropy, and that b... Considering a two-level atom interacting with the competing two-mode field, this paper investigates the entangle- ment between the two-level atom and the two-mode field by using the quantum reduced entropy, and that between the two-mode field by using the quantum relative entropy of entanglement. It shows that the two kinds of entanglement are dependent on the relative coupling strength of atom-field and the atomic distribution, and exhibit the periodical evolu- tion. The maximal atom–field entanglement state can be prepared via the appropriate selection of system parameters and interaction time. 展开更多
关键词 量子纠结 双模竞争系统 约简方程 相对熵
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Global stability of bistable traveling wavefronts for a three-species Lotka-Volterra competition system with nonlocal dispersal
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作者 Yu-Cai Hao Guo-Bao Zhang 《International Journal of Biomathematics》 SCIE 2023年第5期87-110,共24页
This paper is devoted to the study of traveling wavefronts for a three-component Lotka-Volterra system with nonlocal dispersal.This system arises in the study of three-species competition model in which there is no co... This paper is devoted to the study of traveling wavefronts for a three-component Lotka-Volterra system with nonlocal dispersal.This system arises in the study of three-species competition model in which there is no competition between two of these three species.It has been shown that this system admits a bistable traveling wavefront.In this paper,we further investigate the stability of bistable traveling wavefronts.By constructing suitable super-and sub-solutions and using a dynamical system approach,we obtain the globally asymptotic stability of the bistable traveling wavefronts. 展开更多
关键词 Three-species competition system nonlocal dispersal bistable traveling wavefronts global stability UNIQUENESS
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Treatment of Helicobacter pylori with potassium competitive acid blockers:A systematic review and meta-analysis
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作者 Joseph Edwin Kanu Jonathan Soldera 《World Journal of Gastroenterology》 SCIE CAS 2024年第9期1213-1223,共11页
BACKGROUND Helicobacter pylori(H.pylori)infects over half the global population,causing gastrointestinal diseases like dyspepsia,gastritis,duodenitis,peptic ulcers,GMALT lymphoma,and gastric adenocarcinoma.Eradicating... BACKGROUND Helicobacter pylori(H.pylori)infects over half the global population,causing gastrointestinal diseases like dyspepsia,gastritis,duodenitis,peptic ulcers,GMALT lymphoma,and gastric adenocarcinoma.Eradicating H.pylori is crucial for treating and preventing these conditions.While conventional proton pump inhibitor(PPI)-based triple therapy is effective,there’s growing interest in longer acid suppression therapies.Potassium competitive acid blocker(P-CAB)triple and dual therapy are new regimens for H.pylori eradication.Initially used in Asian populations,vonoprazan(VPZ)has been recently Food and Drug Administration-approved for H.pylori eradication.AIM To assess the efficacy of regimens containing P-CABs in eradicating H.pylori infection.METHODS This study,following PRISMA 2020 guidelines,conducted a systematic review and meta-analysis by searching MEDLINE and Scopus libraries for randomized clinical trials(RCTs)or observational studies with the following command:[("Helicobacter pylori"OR"H pylori")AND("Treatment"OR"Therapy"OR"Eradication")AND("Vonaprazan"OR"Potassium-Competitive Acid Blocker"OR"P-CAB"OR"PCAB"OR"Revaprazan"OR"Linaprazan"OR"Soraprazan"OR"Tegoprazan")].Studies comparing the efficacy of P-CABs-based treatment to classical PPIs in eradicating H.pylori were included.Exclusion criteria included case reports,case series,unpublished trials,or conference abstracts.Data variables encompassed age,diagnosis method,sample sizes,study duration,intervention and control,and H.pylori eradication method were gathered by two independent reviewers.Meta-analysis was performed in R software,and forest plots were generated.RESULTS A total of 256 references were initially retrieved through the search command.Ultimately,fifteen studies(7 RCTs,7 retrospective observational studies,and 1 comparative unique study)were included,comparing P-CAB triple therapy to PPI triple therapy.The intention-to-treat analysis involved 8049 patients,with 4471 in the P-CAB intervention group and 3578 in the PPI control group across these studies.The analysis revealed a significant difference in H.pylori eradication between VPZ triple therapy and PPI triple therapy in both RCTs and observational studies[risk ratio(RR)=1.17,95%confidence interval(CI):1.11-1.22,P<0.0001]and(RR=1.13,95%CI:1.09-1.17,P<0.0001],respectively.However,no significant difference was found between tegoprazan(TPZ)triple therapy and PPI triple therapy in both RCTs and observational studies(RR=1.04,95%CI:0.93-1.16,P=0.5)and(RR=1.03,95%CI:0.97-1.10,P=0.3),respectively.CONCLUSION VPZ-based triple therapy outperformed conventional PPI-based triple therapy in eradicating H.pylori,positioning it as a highly effective first-line regimen.Additionally,TPZ-based triple therapy was non-inferior to classical PPI triple therapy. 展开更多
关键词 Helicobacter pylori infection Potassium competitive acid blockers Proton pump inhibitors Vonoprazan AMOXICILLIN
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Assessing the Efficacy of Wheat-Soybean Based Intercropping System at Different Plant Densities in Bambili, Cameroon
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作者 Lendzemo E. Tatah Jeazet K. Teitiogo +3 位作者 Oben Tom Tabi Tange D. Achiri Njualem D. Khumbah Chi Christopher Tamu 《American Journal of Plant Sciences》 CAS 2024年第4期235-251,共17页
Wheat is one of the most important cereals in the world, serving as a staple for millions globally. In the wake of the geopolitical crisis between Russia and Ukraine, it has become incumbent for many countries to inve... Wheat is one of the most important cereals in the world, serving as a staple for millions globally. In the wake of the geopolitical crisis between Russia and Ukraine, it has become incumbent for many countries to invest in wheat production. Improving cropping systems for wheat production is paramount. Intercropping cereals with legumes has tremendous advantages. Therefore, this study was designed to optimize wheat production by intercropping it with soybean at different densities. Between March and August 2023, a randomized complete block design trial was conducted in Bambili, North West of Cameroon with treatments T1 (wheat monocrop at 200,000 plants ha<sup>−</sup><sup>1</sup>), T2 (soybean monocrop at 250,000 plants ha<sup>−</sup><sup>1</sup>), T3 (200,000 wheat and 125,000 soybean ha<sup>−</sup><sup>1</sup>), T4 (100,000 wheat and 250,000 soybean ha<sup>−</sup><sup>1</sup>), T5 (200,000 wheat and 250,000 soybean ha<sup>−</sup><sup>1</sup>) and T6 (100,000 wheat and 125,000 soybean ha<sup>−</sup><sup>1</sup>). Results revealed that growth parameters of wheat were not significantly influenced by monocrop or intercrop. The yield of wheat was significantly higher in the monocrop than the intercrop treatments, with slight variation amongst the intercrop treatments. Soybean yield was higher in the monocrop than in the intercrop, with no variations amongst the intercrop treatments. Only the land equivalence ratio (LER) for T5 was greater than 1.0. The competitive ratio for T5 was 0.54 for wheat and 1.90 for soybean, comparatively lower than the other monocrop treatments. Intercropping wheat and soybean at 200,000:250,000 ratio is recommended. 展开更多
关键词 Competitive Ration Land Equivalence Ration INTERCROP SOYBEAN WHEAT
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Discussion on the Application of Technical and Tactical Skills in Mixed Martial Arts Competitions
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作者 Yu Huang 《Journal of Contemporary Educational Research》 2024年第2期8-13,共6页
This article mainly analyzes the application of technical and tactical skills in mixed martial arts competitions,including mixed martial arts and its competition characteristics,the main application significance of te... This article mainly analyzes the application of technical and tactical skills in mixed martial arts competitions,including mixed martial arts and its competition characteristics,the main application significance of technical and tactical skills in mixed martial arts competitions,and its primary application strategies.It is hoped that this analysis can provide some guidelines for the appropriate application of mixed martial arts athletes’technical and tactical skills to improve their winning rate in mixed martial arts competitions. 展开更多
关键词 Mixed martial arts competition Technical and tactical skills Fighting awareness Fighting movements competition rhythm
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Competition system for automatically evaluating edge detection algorithms based on the evolutionary game theory
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作者 Peng Hong Ding Guangtai +1 位作者 Zhang Huiran Hu Dongli 《The Journal of China Universities of Posts and Telecommunications》 EI CSCD 2019年第5期49-59,共11页
An ensemble learning algorithm based on game theory is proposed to evaluate algorithms of image analysis and image feature extraction.A competition system is established to implement the algorithm for evaluating the a... An ensemble learning algorithm based on game theory is proposed to evaluate algorithms of image analysis and image feature extraction.A competition system is established to implement the algorithm for evaluating the applicability and efficiency of different edge detection algorithms.Through the game in the algorithm competition system,the most suitable algorithm as a winner in the competition can be selected.A group of optimal parameters for the corresponding edge detection can also be found.Firstly,based on the evolutionary game theory,a strategy of the competition of edge extraction algorithms is developed.Secondly,after selecting the most suitable algorithm from the candidates,the overall parameters are optimized.Experiments show that for a specific class of images,several candidate algorithms can be used as a class of preference algorithms based on the final evolutionary result.When analyzing the images,the priority algorithm can be recommended as the best edge detection algorithm from these reference algorithms.It is more effective than traditional methods in determining an algorithm and choosing parameters. 展开更多
关键词 algorithm evaluation competition system game theory edge detection
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The minimal speed of traveling wave fronts for a three-cornponent competition system with nonlocal dispersal
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作者 Juan He Guo-Bao Zhang 《International Journal of Biomathematics》 SCIE 2021年第7期215-226,共12页
In this paper,we study the linear determinacy of the minimal speed of traveling wave-fronts for a three-component competition system with nonlocal dispersal.We first trans-form this system into a cooperative system.Th... In this paper,we study the linear determinacy of the minimal speed of traveling wave-fronts for a three-component competition system with nonlocal dispersal.We first trans-form this system into a cooperative system.Then,by constructing suitable upper solu-tions,we give some general conditions to ensure the linear determinacy of the minimalspeed.Finally,we provide some more precise conditions that only rely on the parametersof the system such that the linear determinacy of the minimal speed is assured. 展开更多
关键词 Three-component competition system nonlocal dispersal traveling waves the minimal speed linear determinacy
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GLOBAL ATTRACTIVITY IN A PERIODIC COMPETITION SYSTEM WITH FEEDBACK CONTROLS 被引量:5
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作者 翁佩萱 《Acta Mathematicae Applicatae Sinica》 SCIE CSCD 1996年第1期11-20,共10页
WENGPEIXUAN(翁佩萱)(DepartmentofMathematics,SouthChinaNormalUniversity,Guangzhou510631,China)GLOBALATTRACTIVITY... WENGPEIXUAN(翁佩萱)(DepartmentofMathematics,SouthChinaNormalUniversity,Guangzhou510631,China)GLOBALATTRACTIVITYINAPERIODICCOMPET... 展开更多
关键词 GLOBAL ATTRACTIVITY PERIODIC solution competition system FEEDBACK control
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Soccer League Competition Algorithm, a New Method for Solving Systems of Nonlinear Equations 被引量:6
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作者 Naser Moosavian Babak Kasaee Roodsari 《International Journal of Intelligence Science》 2014年第1期7-16,共10页
This paper introduces Soccer League Competition (SLC) algorithm as a new optimization technique for solving nonlinear systems of equations. Fundamental ideas of the method are inspired from soccer leagues and based on... This paper introduces Soccer League Competition (SLC) algorithm as a new optimization technique for solving nonlinear systems of equations. Fundamental ideas of the method are inspired from soccer leagues and based on the competitions among teams and players. Like other meta-heuristic methods, the proposed technique starts with an initial population. Population individuals called players are in two types: fixed players and substitutes that all together form some teams. The competition among teams to take the possession of the top ranked positions in the league table and the internal competitions between players in each team for personal improvements results in the convergence of population individuals to the global optimum. Results of applying the proposed algorithm in solving nonlinear systems of equations demonstrate that SLC converges to the answer more accurately and rapidly in comparison with other Meta-heuristic and Newton-type methods. 展开更多
关键词 SOCCER LEAGUE competition Nonlinear EQUATIONS META-HEURISTIC ALGORITHM
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GLOBAL ATTRACTIVITY IN A N-SPECIES COMPETITION DIFFERENCE SYSTEM
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作者 Yuan Cunde Cui Xiaoying Liu Pingzhou(Shanxi Normal University,Linfen,Shanxi 041004) 《生物数学学报》 CSCD 北大核心 1995年第3期1-8,共8页
A population of interacting species is considered which is governed by a system of nonlinear difference equation.In the case of the interacting species with competition,a sufficient condition for global attractivity o... A population of interacting species is considered which is governed by a system of nonlinear difference equation.In the case of the interacting species with competition,a sufficient condition for global attractivity of an equilibrium state is derived.The result can be considered as a best discrete approximation of the continuous system. 展开更多
关键词 LOTKA-VOLTERRA DIFFERENCE EQUATIONS competition global attractivity.
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Existence and stability of invasion traveling waves for a competition system with random vs.nonlocal dispersals
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作者 Jiao Wang Zhixian Yu Yanling Meng 《International Journal of Biomathematics》 SCIE 2019年第1期71-91,共21页
The purpose of this paper is to investigate asymptotic behaviors of the solutions for a competition system with random vs.nonlocal dispersal.We first prove the existence of invasion traveling waves via using the theor... The purpose of this paper is to investigate asymptotic behaviors of the solutions for a competition system with random vs.nonlocal dispersal.We first prove the existence of invasion traveling waves via using the theory of asymptotic speeds of spread.Then we prove the invasion traveling waves are exponentially stable as perturbation in some exponentially weighted spaces by using the weighted energy and the squeezing technique. 展开更多
关键词 EXISTENCE STABILITY COMPETITIVE system comparison PRINCIPLE WEIGHTED energy
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Deviations of Steady States of the Traveling Wave to a Competition Diffusion System with Random Perturbation
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作者 Xiaorong Hu Yanbin Tang 《Journal of Applied Mathematics and Physics》 2015年第5期496-508,共13页
This paper considers the asymptotic dynamics of steady states to the Lotka-Volterra competition diffusion systems with random perturbations by two-parameter white noise on the whole real line. By the fundamental solut... This paper considers the asymptotic dynamics of steady states to the Lotka-Volterra competition diffusion systems with random perturbations by two-parameter white noise on the whole real line. By the fundamental solution of heat equation, we get the asymptotic fluctuating behaviors near the stable states respectively. That is, near the steady state (u,v)=(0,1), the mean value Eu(x,t) is shifted above the equilibrium u=0 and Ev(x,t) is shifted below the equilibrium v=1. However, near the steady state (u,v)=(1,0), the mean value Eu(x,t) is shifted below the equilibrium u =1 and Eu(x,t)=0. 展开更多
关键词 LOTKA-VOLTERRA competition Diffusion system Random PERTURBATION TWO-PARAMETER White Noise
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EXTINCTION IN A GILPIN-AYALA COMPETITION SYSTEM WITH THE EFFECT OF TOXIC SUBSTANCES
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作者 Danhong Wang 《Annals of Differential Equations》 2015年第1期68-73,共6页
In this paper,we consider a two dimensional Gilpin-Ayala competition system with the effect of toxic substances.We prove that one of components is driven to extinction while the other one is stable under some conditio... In this paper,we consider a two dimensional Gilpin-Ayala competition system with the effect of toxic substances.We prove that one of components is driven to extinction while the other one is stable under some conditions.As a result,we generalize the previous results. 展开更多
关键词 Gilpin-Ayala competition system EXTINCTION TOXIC substances DELAY
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Realization of the Legal Path of Competition Policy in the New Age and the Significance of the Fair Competition Review System
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作者 Hao Xu 《教育研究前沿(中英文版)》 2019年第3期235-238,共4页
Against the background of economic globalization and domestic deepening reform in the new era,it is of great significance to establish the basic position of competition policy in the new era for the overall work of co... Against the background of economic globalization and domestic deepening reform in the new era,it is of great significance to establish the basic position of competition policy in the new era for the overall work of comprehensively deepening reform,comprehensively governing the country by law and transforming the strategy of economic development.This paper introduces the basic connotation and great significance of China's competition policy in the new era,and on this basis analyzes and summarizes the feasible legal path of China's competition policy,which focuses on the construction of the fair audit system is analyzed,in order to boost China's economic development. 展开更多
关键词 Fair competition Review system competition Policy New Age
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