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81.
82.
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
83.
翁佩萱 《应用数学学报(英文版)》1996,12(1):11-21
WENGPEIXUAN(翁佩萱)(DepartmentofMathematics,SouthChinaNormalUniversity,Guangzhou510631,China)GLOBALATTRACTIVITYINAPERIODICCOMPET... 相似文献
84.
Pelegrin Blas; Fernandez Pascual; Suarez Rafael; Garcia Maria Dolores 《IMA Journal of Management Mathematics》2006,17(4):373-385
** E-mail: pelegrin{at}um.es Firms normally use either a mill price or a delivered pricepolicy, depending on market conditions (type of good, transportationway, customers location, costs, etc). In this paper, the problemof selecting the best location for an entering firm in competitionwith some pre-existing firms, under each price policy, is studiedon a network for the first time. With mill pricing, an equilibriumin price rarely exists and it is assumed that all competingfirms set a common mill price for all customers. With deliveredpricing, there exists a Nash equilibrium in price and it isassumed that the equilibrium price in each area is offered tothe customers in that area. In both cases, we consider thatcustomers buy from the cheapest facility and the same rulesare used for tie breaking in the lowest cost. While the profitmaximization problem for the entering firm always has optimalsolutions under mill pricing, this problem might not have anoptimal solution under delivered pricing. We show some discretizationresults and give procedures to find the full set of optimal,or -optimal, solutions to the problem under the two price policies.A comparison of results with the two price policies is givenby using an illustrative example. 相似文献
85.
In this paper, we consider a delayed nonautonomous n-species Gilpin–Ayala type competitive system, which is more general and more realistic then classical Lotka–Volterra type competition model. For each rn, we establish a series of criteria under which r of the species in the system are permanent while the remaining n-r species are driven to extinction. 相似文献
86.
We discuss a novel minimal model for binocular rivalry (and more generally perceptual dominance) effects. The model has only three state variables, but nonetheless exhibits a wide range of input and noise-dependent switching. The model has two reciprocally inhibiting input variables that represent perceptual processes active during the recognition of one of the two possible states and a third variable that represents the perceived output. Sensory inputs only affect the input variables.We observe, for rivalry-inducing inputs, the appearance of winnerless competition in the perceptual system. This gives rise to a behaviour that conforms to well-known principles describing binocular rivalry (the Levelt propositions, in particular proposition IV: monotonic response of residence time as a function of image contrast) down to very low levels of stimulus intensity. 相似文献
87.
Analysis of dynamics in a general intraguild predation model with intraspecific competition 下载免费PDF全文
This paper is devoted to studying the dynamical properties of a general intraguild predation model with intraspecific competition. We first investigate the stability of all possible equilibria in relation to the ecological parameters, and then study the long time behavior of the solution. Moreover, we provide a detailed analysis of dynamics of a IGP model with linear functional response and intraspecific competition. Our results show that the impact of the intraspecific competition essentially increases the dynamical complexity of the system. 相似文献
88.
Stability and Hopf bifurcation of a delayed predator-prey system with nonlocal competition and herd behaviour 下载免费PDF全文
In this paper, we investigate the stability and Hopf bifurcation of a diffusive predator-prey system with herd behaviour. The model is described by introducing both time delay and nonlocal prey intraspecific competition. Compared to the model without time delay, or without nonlocal competition, thanks to the together action of time delay and nonlocal competition, we prove that the first critical value of Hopf bifurcation may be homogenous or non-homogeneous. We also show that a double-Hopf bifurcation occurs at the intersection point of the homogenous and non-homogeneous Hopf bifurcation curves. Furthermore, by the computation of normal forms for the system near equilibria, we investigate the stability and direction of Hopf bifurcation. Numerical simulations also show that the spatially homogeneous and non-homogeneous periodic patters. 相似文献
89.
《Operations Research Letters》2020,48(6):787-791
We analyze the equilibrium of a behavioral newsvendor game featuring oligopoly competition, where each newsvendor’s decision is driven by a reference effect regarding her potential profit. We find that the equilibrium order quantities are characterized by behavioral critical fractiles, where each newsvendor only accounts for the actions of competitors with smaller behavioral critical fractiles. Our result generalizes findings from recent literature on duopoly newsvendor competition with reference effects. 相似文献
90.
In this paper, we investigate the population dynamics of a two-species Lotka-Volterra
competition system arising in river ecology. An interesting feature of this modeling system lies in the boundary conditions at the downstream end, where the populations may be exposed to differing magnitudes of loss of individuals. By applying the theory of principal eigenvalue and monotone dynamical systems, we obtain a complete understanding on the global dynamics, which suggests that slower dispersal is selected for. Our results can be seen as a further development of a recent work by Tang and Chen (J. Differential Equations, 2020, 2020(269), 1465--1483). 相似文献