Intermittent random walks: transport regimes and implications on search strategies
Intermittent random walks: transport regimes and implications on search strategies
复制标题
间歇随机游走：传输机制及其对搜索策略的影响
DOI：
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发表时间：
2011
期刊：
影响因子：
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通讯作者：
V. Méndez
中科院分区：
文献类型：
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作者：
I. G. Portillo;Daniel Campos;V. Méndez
我们构建了一个粒子的传输模型，交替休息的随机持续时间和随机速度的航班。该模型提供了一个平衡方程的介观粒子密度从连续时间的随机行走框架。通过假设等待时间和飞行持续时间的分布的幂律（对于具有有限矩的任何速度分布），我们发现该模型可以产生从次扩散到弹道的所有传输状态，这取决于分布的特征指数的值。此外，如果指数满足一个简单的关系，它示出了如何的分布之间的尾部的竞争引起的扩散运输。最后，我们将探讨如何在一个最佳的搜索问题，其中一个单独的搜索器寻找一个目标分布（异质性）在空间中的间歇性运输过程的细节影响的成功概率。所有的结果都方便地与数值模拟检查。
We construct a transport model for particles that alternate rests of random duration and flights with random velocities. The model provides a balance equation for the mesoscopic particle density obtained from the continuous-time random walk framework. By assuming power laws for the distributions of waiting times and flight durations (for any velocity distribution with finite moments) we have found that the model can yield all the transport regimes ranging from subdiffusion to ballistic depending on the values of the characteristic exponents of the distributions. In addition, if the exponents satisfy a simple relationship it is shown how the competition between the tails of the distributions gives rise to a diffusive transport. Finally, we explore how the details of this intermittent transport process affect the success probability in an optimal search problem where an individual searcher looks for a target distributed (heterogeneously) in space. All the results are conveniently checked with numerical simulations.