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101.
Evolution of Chinese airport network 总被引:2,自引:0,他引:2
With the rapid development of the economy and the accelerated globalization process, the aviation industry plays a more and more critical role in today’s world, in both developed and developing countries. As the infrastructure of aviation industry, the airport network is one of the most important indicators of economic growth. In this paper, we investigate the evolution of the Chinese airport network (CAN) via complex network theory. It is found that although the topology of CAN has remained steady during the past few years, there are many dynamic switchings inside the network, which have changed the relative importance of airports and airlines. Moreover, we investigate the evolution of traffic flow (passengers and cargoes) on CAN. It is found that the traffic continues to grow in an exponential form and has evident seasonal fluctuations. We also found that cargo traffic and passenger traffic are positively related but the correlations are quite different for different kinds of cities. 相似文献
102.
Serge Galam 《Physica A》2010,389(17):3619-3054
Public debates driven by incomplete scientific data where nobody can claim absolute certainty, due to the current state of scientific knowledge, are studied. The cases of evolution theory, global warming and H1N1 pandemic influenza are investigated. The first two are of controversial impact while the third is more neutral and resolved. To adopt a cautious balanced attitude based on clear but inconclusive data appears to be a lose-out strategy. In contrast overstating arguments with incorrect claims which cannot be scientifically refuted appears to be necessary but not sufficient to eventually win a public debate. The underlying key mechanisms of these puzzling and unfortunate conclusions are identified using the Galam sequential probabilistic model of opinion dynamics (Galam, 2002 [4], Galam, 2005 [18], Galam and Jacobs, 2007 [19]). It reveals that the existence of inflexible agents and their respective proportions are the instrumental parameters to determine the faith of incomplete scientific data in public debates. Acting on one’s own inflexible proportion modifies the topology of the flow diagram, which in turn can make irrelevant initial supports. On the contrary focusing on open-minded agents may be useless given some topologies. When the evidence is not as strong as claimed, the inflexibles rather than the data are found to drive the opinion of the population. The results shed a new but disturbing light on designing adequate strategies to win a public debate. 相似文献
103.
Thomas Lorenz 《Journal of Mathematical Analysis and Applications》2018,457(2):1502-1567
Applications in robust control problems and shape evolution motivate the mathematical interest in control problems whose states are compact (possibly non-convex) sets rather than vectors. This leads to evolutions in a basic set which can be supplied with a metric (like the well-established Pompeiu–Hausdorff distance), but it does not have an obvious linear structure. This article extends differential inclusions with state constraints to compact-valued states in a separable Hilbert space H. The focus is on sufficient conditions such that a given constraint set (of compact subsets) is viable a.k.a. weakly invariant. Our main result extends the tangential criterion in the well-known viability theorem (usually for differential inclusions in a vector space) to the metric space of non-empty compact subsets of H. 相似文献
104.
105.
物流企业与银行之间的良好合作关系是物流金融业务继续发展的前提和基础。以仓单质押融资业务为例,运用演化博弈理论对物流企业与银行之间的监督包庇问题进行了分析,构建复制动态方程和运用动态相位图分析群体策略的演化过程及结果,为建立良好的合作关系提供理论依据。分析结果表明:该动态系统的演化方向受到博弈支付矩阵以及系统的初始状态的影响。银行监督成本、银行的收益损失、物流企业的包庇成本和物流企业的罚金是影响演化结果的关键性因素。通过外部力量的加入,可促使系统演化至(不包庇,不监督)这一期望演化稳定策略。 相似文献
106.
In this paper, applying the theory of semigroups of operators to evolution family and Banach fixed point theorem, we prove the existence and uniqueness of an (a) almost automorphic (weighted pseudo almost automorphic) mild solution of the semilinear evolution equation x′(t)=A(t)x(t)+f(t,x(t)) in Banach space under conditions. 相似文献
107.
Pierre-A. Vuillermot 《Journal of Functional Analysis》2010,259(11):2923-2190
In this article we provide a set of sufficient conditions that allow a natural extension of Chernoff's product formula to the case of certain one-parameter family of functions taking values in the algebra L(B) of all bounded linear operators defined on a complex Banach space B. Those functions need not be contraction-valued and are intimately related to certain evolution operators U(t,s)0?s?t?T on B. The most direct consequences of our main result are new formulae of the Trotter-Kato type which involve either semigroups with time-dependent generators, or the resolvent operators associated with these generators. In the general case we can apply such formulae to evolution problems of parabolic type, as well as to Schrödinger evolution equations albeit in some very special cases. The formulae we prove may also be relevant to the numerical analysis of non-autonomous ordinary and partial differential equations. 相似文献
108.
We study the phenomenon of finite time blow-up in solutions of the homogeneous Dirichlet problem for the parabolic equation
109.
In this paper a two-stage game that involves three container terminals located in Karachi Port in Pakistan is discussed. In the first stage, the three terminals have to decide on whether to act as a singleton or to enter into a coalition with one or both of the other terminals. The decision at this stage should presumably be based on the predicted outcome for the second stage. The second stage is here modelled as a Bertrand game with one outside competitor, the coalition and the terminal in Karachi Port (if any) that has not joined the coalition. Furthermore, three partial and one grand coalition among the three terminals at Karachi Port are investigated. The concepts of “characteristic function” and “core” are used to analyse the stability of these coalitions and this revealed that one combination does not satisfy the superadditivity property of the characteristic function and can therefore be ruled out. The resulting payoffs (profits) of these coalitions are analysed on the basis of “core”. The best payoff for all players is in the case of a “grand coalition”. However, the real winner is the outsider (the terminal at the second port) which earns a better payoff without joining the coalition, and hence will play the role of the “orthogonal free-rider”. 相似文献
110.
在网站动态竞争模型的基础上,建立了含有真正的合作关系的网站竞争模型.随后对二维的特殊情况进行了定性分析,结合给出的数值模拟图,分析了模型中的相关系数对系统的作用,并针对分析的结果讨论了影响网站发展的主要因素. 相似文献