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51.
Houqin Su Xuncheng Huang Xuncheng Huang Xiaoning Xu 《Journal of mathematical chemistry》2008,43(3):1273-1284
A three-dimensional bio-reactor model of exploitative competition of two predator organisms with inhibition responses for
the same renewable organism with reproductive properties is considered. By constructing a modified Lyapunov function and using
LaSalle’s invariant principle, it is shown that the lower “break-even” concentration predator organism survives in the competition.
相似文献
52.
The main purpose of this paper is to study the persistence of the general multispecies competition predator-pray system with Holling Ⅲ type functional response.In this system,the competition among predator species and among prey species are simultaneously considered.By using the comparison theory and qualitative analysis,the sufficient conditions for uniform strong persistence are obtained. 相似文献
53.
Winfried Just 《Journal of Mathematical Analysis and Applications》2008,348(2):620-636
It is demonstrated that a Kolmogorov-type competition model featuring species allocation and gain functions can possess multiple coexistence states. Two examples are constructed: one in which the two competing species possess rectangular allocation functions but distinct gain functions, and the other in which one species has a rectangular allocation function, the second species has a bi-rectangular allocation function, and the two species share a common gain function. In both examples, it is shown that the species nullclines may intersect multiple times within the interior of the first quadrant, thus creating both locally stable and unstable equilibrium points. These results have important applications in the study of plant competition for sunlight, in which the allocation functions describe the vertical placement of leaves for two competing species, and the gain functions represent rates of photosynthesis performed by leaves at different heights when shaded by overlying leaves belonging to either species. 相似文献
54.
企业集团是资本的集合体,它在资本本质的推动下,不断寻求资本增值的最大化。但是我国企业集团由于受经济体制转换期的影响,以及自身经验的不足,未能正确定位集团的发展领域,从而未能实现资本的增值。文章根据我国企业集团当前存在的问题,结合项目实践中的体会,讨论了如何正确认识资本增值域,以及如何正确选择与优化资本增值域 相似文献
55.
K. U. Schreiber J. -P. R. Wells G. E. Stedman 《General Relativity and Gravitation》2008,40(5):935-943
Large ring lasers with a cavity Q well above 1012 are characterized by extremely narrow line-widths and high coherence. At this point, active Sagnac interferometers do not
quite reach the quantum limit. In this paper, we will explore the current status of this technology and look at the various
noise processes involved with large ring lasers rigidly mounted to the Earth crust. 相似文献
56.
Spatial competition facility location models: Definition,formulation and solution approach 总被引:2,自引:0,他引:2
Models are presented for locating a firm's production facilities and determining production levels at these facilities so as to maximize the firm's profit. These models take into account the changes in price at each of the spatially separated markets that would result from the increase in supply provided by the new facilities and also from the response of competing firms. Two different models of spatial competition are presented to represent the competitive market situation in which the firm's production facilities are being located. These models are formulated as variational inequalities; recent sensitivity analysis results for variational inequalities are used to develop derivatives of the prices at each of the spatially separated markets with respect to the production levels at each of the new facilities. These derivatives are used to develop a linear approximation of the implicit function relating prices to productions. A heuristic solution procedure making use of this approximation is proposed. 相似文献
57.
从生态学视角来研究企业竞争的动态演化已成为一个研究热点,针对现有研究文献中只讨论二维系统的不足,以三个企业之间的竞争为例,构造了企业间竞争的三维模型,运用微分方程稳定性理论分析其稳定性,并由此揭示出企业间竞争的动力学机制.数值仿真结果表明,该三维模型能有效地模拟企业间竞争的动态演化规律. 相似文献
58.
59.
本文在碳交易机制下,考虑制造商之间存在竞争且减排成本系数为低碳制造商私有信息的情况,分别构建信息完全对称和信息非对称情形下的供应链模型,对低碳制造商减排率和产品销售价格进行决策。通过引入由批发价和成本共担组成的联合契约,促使低碳制造商传递真实的减排成本信息,并通过算例对碳交易价格和减排成本系数等进行灵敏度分析。研究发现:引入联合契约能够使得信息非对称下的供应链利润基本达到集中决策水平;碳交易价格的增加会激励制造商积极减排、降低碳排放总量、提高供应链利润;低碳制造商减排成本系数的降低有助于减少碳排放量、增加产品市场需求、实现供应链利润增长。 相似文献
60.
In this paper we investigate a two-species competitive chemotaxis Keller–Segel system. We first obtain the local existence and global existence of classical solutions and then study the asymptotic behavior of the solutions. 相似文献