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991.
In most previous studies of public goods game, individuals conventionally donate their contributions equally to the games they participate in. We develop an extended public goods game model, in which individuals distribute their contributions based on the groups’ qualities. Namely, the individuals are allowed to increase their investment to the superior groups at the expense of the nasty ones. The quality of a group is positively correlated with its cooperation level. In numerical simulations, synchronized stochastic strategy updating rule based on pairwise comparison for a fixed noise level is adopted. The results show that the high-quality group preference mechanism can greatly improve cooperation, compared with conventional models. Besides, the system with stronger preference toward high-quality groups performs better. Investigation of wealth distribution at equilibrium reveals that cooperators’ wealth appreciates with the increase of preference degree when cooperators take up the same fraction of the population. 相似文献
992.
993.
Zu-Hua Yang Chao-Yun Long Shuei-Jie Qin Zheng-Wen Long 《International Journal of Theoretical Physics》2010,49(3):644-651
The DKP equation with Dirac oscillator potential for spin-0 particles has been studied when both space-space noncommutativity
and momentum-momentum noncommutativity are considered. The exact wave functions and corresponding energy levels have been
found. Due to the noncommutative effect, the energy spectrum is not degenerate. 相似文献
994.
An idea of using laser Doppler velocimeter (LDV) to measure the velocity for the vehicle inertial navigation system was put forward. The principle of measuring its own velocity with laser Doppler technique was elaborated and reference-beam LDV was designed. Then Doppler signal was processed by tracking filter, frequency spectrum refinement and frequency spectrum correction algorithm. The result of theory and experiment showed that the reference-beam LDV solved the problem that dual-beam LDV cannot be used for measuring when the system was out of focus. Doppler signal was tracked so that signal-to-noise ratio was improved, and the accuracy of the system was enhanced by the technology of frequency spectrum refinement and correction. The measurement mean error was less than 1.5% in velocity range of 0-30 m/s. 相似文献
995.
An experimental demonstration of using a single longitudinal mode solid-state laser source in laser Doppler velocimeter (LDV) is presented. The technology of frequency spectrum correction is used in processing Doppler signal. The results of the experiments show that: the magnitude and signal-to-noise ratio (SNR) of Doppler signal are both enhanced by the solid-state laser; the measurement accuracy of LDV is improved by the technology of frequency spectrum correction, and the variance of the measured Doppler frequency is larger than the Cramer-Rao low bound (CRLB) of Doppler frequency about one order of magnitude. 相似文献
996.
Permanence for General Nonautonomous Impulsive Population Systems of Functional Differential Equations and Its Applications 总被引:1,自引:0,他引:1
In this paper, we investigate general impulsive nonautonomous population dynamical systems of functional differential equations.
By utilizing the method of multiple Liapunov-like functionals to construct the permanence region, a general criterion on the
permanence for the system is established. Furthermore, as applications of this general criterion, a class of impulsive nonautonomous
n-species Lotka–Volterra competitive systems with delays and a class of impulsive nonautonomous 3-species Lotka–Volterra food
chain systems with delays are discussed. Some new and useful sufficient conditions on the permanence for these systems are
established. 相似文献
997.
A graph G is induced matching extendable if every induced matching of G is included in a perfect matching of G. A graph G is generalized induced matching extendable if every induced matching of G is included in a maximum matching of G. A graph G is claw-free, if G dose not contain any induced subgraph isomorphic to K1,3. The k-th power of G, denoted by Gu, is the graph with vertex set V(G) in which two vertices are adjacent if and only if the distance between them is at most k in G. In this paper we show that, if the maximum matchings of G and G3 have the same cardinality, then G3 is generalized induced matching extendable. We also show that this result is best possible. As a result, we show that if G is a connected claw-flee graph, then G3 is generalized induced matching extendable. 相似文献
998.
For a right R-module N, we introduce the quasi-Armendariz modules which are a common generalization of the Armendariz modules and the quasi-Armendariz rings, and investigate their properties. Moreover, we prove that NR is quasi-Armendariz if and only if Mm(N)Mm(R) is quasi-Armendariz if and only if Tm(N)Tm(R) is quasi-Armendariz, where Mm(N) and Tm(N) denote the m×m full matrix and the m×m upper triangular matrix over N, respectively. NR is quasi-Armendariz if and only if N[x]R[x] is quasi-Armendariz. It is shown that every quasi-Baer module is quasi-Armendariz module. 相似文献
999.
This paper studies the demand and capacity management problem in a restaurant system. A queueing-based optimization model with underlying quasi birth-and-death process and state-dependent functions is developed to address the dynamic and nonlinearity difficulties. In particular, our model explicitly captures the demand changes with respect to the system congestion state on a near real-time dynamic basis. With this framework, we empirically examine the relative performance of commonly used strategies for the case of a local restaurant. The study shows that a strategy that balances service quality and cost yields maximum profit. The result indicates that the traditional view of the conflict between service quality and cost can be overcome by using an interdisciplinary perspective of marketing and operations. Both perspectives should be embraced in academic research and industrial practice in capacity planning decisions for services. 相似文献
1000.
中医方药量化研究中“相对药量”的数学模型体系 总被引:11,自引:4,他引:7
建立中医方药量华研究的"相对药量"概念模型体系;方法:运用微分方程理论;提出五种情况下,中药常用量范围内相对药量概念的数学模型,分别为直线模型、指数函数模型、对数函数模型、二次函数模型(开口向上和向下两种),并说明该模型体系的和理性与适应性;结论:相对药量概念核心体系的建立,增加了中医方药"相对药量"可比性的全面性,这对进一步研究单位药乃至方剂中各药在性、味、归经等方面的影响程度及其规律性,将起到至关重要的作用. 相似文献