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141.
在分析经典回购合约的回购价格、回构批量及最高回购率的基础上,进一步讨论当供应商实际允许执行的最高回购率风险波动时,零售商相应的订货策略。建立了回购率风险波动时以利润最大化为目标的数学模型;分别讨论了有无风险波动等3种情况下零售商及供应链总体利润变化。得出了当相关参数风险波动时,零售商相应的最优订货策略。当回购率风险波动时,供应链成员及供应链总的期望利润都会下降。而回购率风险波动零售商却不做相应订货策略调整的话,整个供应链的期望利润跟经典回购时一样,但是零售商的利润会部向供应商转移,产生利润损失。 相似文献
142.
This paper proposes a unified clutter model incorporating the effects of range walk and array rotation for space-time adaptive processing (STAP) in airborne multi-channel early-warning radar. Based on this clutter model, STAP performance is then analyzed from the perspective of covariance matrix tapering (CMT). For STAP performance degradation due to array rotation, a determinate compensation method is proposed based on the CMT method. Numerical examples are provided to verify the analysis and the proposed compensation method. 相似文献
143.
The problem of robust H∞ control for uncertain neutral stochastic systems with time-varying delay is discussed. The parameter uncertaintie is assumed to be time varying norm-bounded. First, the stochastic robust stabilization of the stochastic system without disturbance input is investigated by nonlinear matrix inequality method. Then, a full-order stochastic dynamic output feedback controller is designed by solving a bilinear matrix inequality (BMI), which ensures a prescribed stochastic robust H∞ performance level for the resulting closed loop system with nonzero disturbance input and for all admissible uncertainties. An illustrative example is provided to show the feasibility of the controller and the potential of the proposed technique. 相似文献
144.
The reverse construction and analysis of the networks of molecular interactions are essential for understanding their functions
within cells. In this paper, a logic network model is constructed to investigate the complicated regulation mechanism of shoot
genes of Arabidopsis Thaliana in response to stimuli. The dynamics of the complicated logic network is analyzed, discussed,
and simulated. The simulation results show that the logic network of the active genes of shoot eventually evolves into eleven
attractors under the stimuli, including five 1-periodic and six 2-periodic attractors. Our work provides valuable reference
and guidance for biologists to understand and explain Arabidopsis’ response to external stimuli by experiments. 相似文献
145.
<正> This paper considers finite-time χ-consensus problem for a multi-agent system with firstorderindividual dynamics and switching interaction topologies.Several distributed finite-time consensusrules are constructed for multi-agent dynamics in a unified way with the help of Lyapunovfunction and graph theory as well as homogeneity.Time-invariant non-smooth forms of finite-timeneighbor-based controllers are proposed and a numerical example is shown for illustration. 相似文献
146.
<正> This paper formulates and analyzes a line search method for general nonlinear equalityconstrained optimization based on filter methods for step acceptance and secant methods for searchdirection.The feature of the new algorithm is that the secant algorithm is used to produce a searchdirection,a backtracking line search procedure is used to generate step size,some filtered rules areused to determine step acceptance,second order correction technique is used to reduce infeasibility andovercome the Maratos effect.Global convergence properties of this method are analyzed:under mildassumptions it is showed that every limit point of the sequence of iterates generated by the algorithmis feasible,and that there exists at least one limit point that is a stationary point for the problem.Moreover,it is also established that the Maratos effect can be overcome in our new approach by addingsecond order correction steps so that fast local superlinear convergence to a second order sufficient localsolution is achieved.Finally,the results of numerical experiments are reported to show the effectivenessof the line search filter secant method. 相似文献
147.
China's aerospace enterprises carry on the multinational operation and participate in the international competition and the international division of labor and cooperation positively. This article first analyzs China aerospace enterprises' binary multinational business control objective and constructes its model. Then the article analyzes the tangible and intangible control mechanism of China aerospace enterprises' binary multinational operation respectively. Finally, the article constructs the model of China aerospace enterprises' binary multinational operation mechanisms. 相似文献
148.
A fuzzy particle swarm optimization (PSO) on the basis of elite archiving is proposed for solving multi-objective optimization problems. First, a new perturbation operator is designed, and the concepts of fuzzy global best and fuzzy personal best are given on basis of the new operator. After that, particle updating equations are revised on the basis of the two new concepts to discourage the premature convergence and enlarge the potential search space; second, the elite archiving technique is used during the process of evolution, namely, the elite particles are introduced into the swarm, whereas the inferior particles are deleted. Therefore, the quality of the swarm is ensured. Finally, the convergence of this swarm is proved. The experimental results show that the nondominated solutions found by the proposed algorithm are uniformly distributed and widely spread along the Pareto front. 相似文献
149.
Two pairs of approximation operators, which are the scale lower and upper approximations as well as the real line lower and upper approximations, are defined. Their properties and antithesis characteristics are analyzed. The rough function model is generalized based on rough set theory, and the scheme of rough function theory is made more distinct and complete. Therefore, the transformation of the real function analysis from real line to scale is achieved. A series of basic concepts in rough function model including rough numbers, rough intervals, and rough membership functions are defined in the new scheme of the rough function model. Operating properties of rough intervals similar to rough sets are obtained. The relationship of rough inclusion and rough equality of rough intervals is defined by two kinds of tools, known as the lower (upper) approximation operator in real numbers domain and rough membership functions. Their relative properties are analyzed and proved strictly, which provides necessary theoretical foundation and technical support for the further discussion of properties and practical application of the rough function model. 相似文献
150.
Wang Yang Zhang Naitong Zhang Qinyu Zhang ZhongzhaoAuthor vitae 《系统工程与电子技术(英文版)》2008,19(6):1070-1075
A simplified closed-form analytic solution for UWB impulse signal transmitting through a finitely conducting slab is proposed. The approach first requires evaluating the impulse response of the slab and then convolving it with the specified incident field waveform. To obtain the impulsive transmitting field, either for vertical or horizontal polarization, approximations to the refraction coefficients and propagation loss are made, which can be proved to be accurate enough, comparing with their frequency domain solutions. Thereby, it permits simplified closed-form expressions in the time domain for both terms. The resulting transient response for the transmitting impulse field is then given by convolution of the time domMn refraction coefficients and time domain propagation loss. A numerical example of an incident monocyele transmitting through a slab using this technique, is presented, to illustrate the effective use of the method. 相似文献