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271.
A. Gil M.V. Alania 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2013
We show that the amplitudes of the 27-day variations of galactic cosmic ray (GCR) intensity, solar wind and solar activity parameters have a periodicity with duration of three to four Carrington rotation periods (3–4 CRP). We assume that the general reason for this phenomenon may be related to similar cyclicity of topological structure of the solar magnetic field lines created owing to the asymmetry of turbulent solar dynamo and solar differential rotation transforming the Sun’s poloidal magnetic field to the toroidal (α–ω effect), and vice versa. 相似文献
272.
我国航空公司机票价格博弈分析 总被引:1,自引:0,他引:1
莫浩浩 《西安航空技术高等专科学校学报》2011,29(6):48-51
主要从博弈论完全信息条件下"囚徒困境"的角度,以及完全信息条件下有先后定价次序的价格竞争角度分析我国民航业的双寡头航空公司机票价格定价策略,然后从不完全信息混合博弈角度分析航空公司与民航总局监管博弈,最后根据以上论证对民航总局管控和航空公司机票定价策略提出相关建议。 相似文献
273.
Aiming to the reliable estimates of the ionosphere differential corrections for the satellite navigation system in the presence of the ionosphere anomaly, a fault-tolerance estimating method, which is based on the distributed Kalman filtering, is proposed. The method utilizes the parallel sub-filters for estimating the ionosphere differential corrections. Meanwhile, an infinite norm (IN) method is proposed for the detection of the ionosphere irregularity in the filter processing. Once the anomaly is detected, the sub-filter contaminated by the anomaly measurements will be excluded to ensure the reliability of the estimates. The simulation is conducted to validate the method and the results indicate that the anomaly can be found timely due to the novel fault detection method based on the infinite norm. Because of the parallel sub-filter architecture, the measurements are classified by the spatial distribution so that the ionosphere anomaly can be positioned and excluded more easily. Thus, the method can provide the robust and accurate ionosphere differential corrections. 相似文献
274.
275.
银行业在一国经济活动中具有特殊地位,银行破产将会给一国的经济发展造成很大的负面效应,有效防范和化解金融风险是一国金融体系稳定运行的重要保证。本文从博弈论的角度来分析存款保险制度的作用, 指出存款保险制度有利于银行业的稳定和系统性金融风险的化解。 相似文献
276.
《中国航空学报》2020,33(3):978-989
The optimal guidance problem for an interceptor against a ballistic missile with active defense is investigated in this paper. A class of optimal guidance schemes are proposed based on linear quadratic differential game method and numerical solution of Riccati differential equation. By choosing proper parameters, the proposed guidance schemes are able to drive the interceptor to the target and away from the defender simultaneously. Additionally, fuel cost, control saturation, chattering phenomenon and parameters selection were taken into account. Satisfaction of the proposed guidance schemes of the saddle point condition is proven theoretically. Finally, nonlinear numerical examples are included to demonstrate the effectiveness and performance of the developed guidance approaches. Comparison of control performance between different guidance schemes are presented and analysis. 相似文献
277.
应用博弈论中优势策略的概念和概率的计算方法,通过计算三方的生存概率,讨论了博弈论中的三方对决问题,并通过社会、经济、教育、政治等活动中的事例,介绍了它的部分应用,对处在激烈竞争环境中的个人或组织如何选择对策具有一定的启示。 相似文献
278.
Multi-agent cooperation problems are becoming more and more attractive in both civilian and military applications. In multi-agent cooperation problems, different network topologies will decide different manners of cooperation between agents. A centralized system will directly control the operation of each agent with information flow from a single centre, while in a distributed system, agents operate separately under certain communication protocols. In this paper, a systematic distributed optimization approach will be established based on a learning game algorithm.The convergence of the algorithm will be proven under the game theory framework. Two typical consensus problems will be analyzed with the proposed algorithm. The contributions of this work are threefold. First, the designed algorithm inherits the properties in learning game theory for problem simplification and proof of convergence. Second, the behaviour of learning endows the algorithm with robustness and autonomy. Third, with the proposed algorithm, the consensus problems will be analyzed from a novel perspective. 相似文献
279.
与工商企业不同,IT企业具有市场需求的多样性、高风险性等营销特点。面对国内外企业的竞争,我国IT企业应根据其营销特点,制定出相应的宏观战略和微观策略。 相似文献
280.
俞金元 《南京航空航天大学学报》1998,30(5):507-514
设(a,b)∩→R是一个有界开区间,考虑如下的特征值问题{∑(t,k=r+1)(-1)^kD^k(Pk(x)D^ky)=λ(-1)^rD^2ry,x∈(a,b);D^ky(α)=D^ky(b)=0,k=0,1,…,t-1其中t,r均为正整数,且t〉r≥1,Pk(x)满足某些条件(k=r+1,r+2,…,t)。利用这些条件,运用某些著名不等式和分析技巧,对本文中的变系数微分方程的特征值估计问题,建立 相似文献