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论文/程序题目	作者	下载	主要内容介绍	Hits
Scaling laws of marine predator search behaviour	David W. Sims,Emily J. Southall		Many free-ranging predators have to make foraging decisions with little, if any, knowledge of present resource distribution and availability The optimal search strategy they should use to maximize encounter rates with prey in heterogeneous natural environments remains a largely unresolved issue in ecology1–3. Le´vy walks4 are specialized random walks giving rise to fractal movement trajectories that may represent an optimal solution for searching complex landscapes5. However, the adaptive significance of this putative strategy in response to natural prey distributions remains untested6,7. Here we analyse over a million movement displacements recorded from animal-attached electronic tags to show that diverse marine predators—sharks, bony fishes, sea turtles and penguins—exhibit Le´vy-walk-like behaviour close to a theoretical optimum2. Prey density distributions also display Le´vy-like fractal patterns, suggesting response movements by predators to prey distributions. Simulations show that predators have higher encounter rates when adopting Le´vy-type foraging in natural-like prey fields compared with purely random landscapes. This is consistent with the hypothesis that observed search patterns are adapted to observed statistical patterns of the landscape. This may explain why Le´vy-like behaviour seems to be widespread among diverse organisms3, from microbes8 to humans9, as a ‘rule’that evolved in response to patchy resource distributions.	603
The scaling laws of human travel	D. Brockmann,L. Hufnagel		The dynamic spatial redistribution of individuals is a key driving force of various spatiotemporal phenomena on geographical scales. It can synchronize populations of interacting species, stabilize them, and diversify gene pools1–3. Human travel, for example, is responsible for the geographical spread of human infectious disease4–9. In the light of increasing international trade, intensified human mobility and the imminent threat of an influenza A epidemic10, the knowledge of dynamical and statistical properties of human travel is of fundamental importance. Despite its crucial role, a quantitative assessment of these properties on geographical scales remains elusive, and the assumption that humans disperse diffusively still prevails in models. Here we report on a solid and quantitative assessment of human travelling statistics by analysing the circulation of bank notes in the United States. Using a comprehensive data set of over a million individual displacements, we find that dispersal is anomalous in two ways. First, the distribution of travelling distances decays as a power law, indicating that trajectories of bank notes are reminiscent of scalefree random walks known as Le´vy flights. Second, the probability of remaining in a small, spatially confined region for a time T is dominated by algebraically long tails that attenuate the superdiffusive spread.We show that human travelling behaviour can be described mathematically on many spatiotemporal scales by a two-parameter continuous-time random walk model to a surprising accuracy, and conclude that human travel on geographical scales is an ambivalent and effectively superdiffusive process.	623
中间过程临界现象——分数阶算子理论、方法、进展及其在现代力学中的应用	徐明瑜,谭文长		从物理学特别是力学的观点出发，简要介绍了用以描述物理和力学中的中间过程核临界现象的分数阶算子（尤指分数阶微积分和分数阶微分方程）理论、方法的最新进展以及在现代力学各个领域中的应用，其中也包括了作者今年来在这一领域所作的工作。最后，对这一学科的发展进行了展望和评价	729
Information theory explanation of the fluctuation theorem, maximum entropy production and self-organized criticality in non-equilibrium stationary states	Roderick Dewar		本篇文章将最大信息熵原理应用到非平衡态系统，自然导出了最大熵产生原理、自组织临界性等非平衡态物理系统中的规律	1330
西部系统自组织模型的建立方法	张辉		本文按照自组织理论，指出西部是个开放系统，外界对西部系统的输入流量对西部系统的运动趋势起着决定性作用。所以，控制外界环境的输入流量，引导系统按自组织方式向整体有序微观无序的混沌状态演化，是西部开发的合理模式。	2473

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