Dynamics of Growing Networks and Evolving Media

不断发展的网络和不断发展的媒体的动态

• 批准号: 0227670
• 负责人: Sidney Redner
• 金额: $ 30万
• 依托单位: Trustees of Boston University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2002
• 资助国家: 美国
• 起止时间: 2002-12-15 至 2006-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0227670&HistoricalAwards=false
• 关键词: Dynamics; Growing; Networks; Evolving; Media

0227670RednerThis award supports theoretical investigations into the structure of growing networks. The networks to be studied grow incrementally through popularity-based rules in which nodes that already have a relatively large number of attached links have a higher propensity for gaining new links. This mechanism appears to underlie a variety of networked systems, such as the world-wide web, the Internet, and various biological networks. The primary goal of this research is to develop a comprehensive quantitative understanding of network structure through the formulation and analysis of the governing rate equations for the evolution of prototypical network models.There are several directions in which research on network structure will be pursued. The role of decay processes, such as the removal of nodes or of links at a finite rate, on the integrity of networks will be studied. Another project will focus on the percolation properties of networks that grow by independent node and link creation events. The rate equation approach will also be extended to treat protein interaction networks in which the growth mechanisms model fundamental processes of small biological organisms, such as yeasts and bacteria. In addition to studying local network properties, such as the degree distribution, effort will be devoted to revealing community structures - tightly linked subnetworks with weaker linkages between communities - within networks. A parallel effort will be devoted to studying porous networks that evolve due to the interaction of a reactive fluid that flows through the medium. In the case of filtration, the pore space is gradually constricted, because of trapping of suspended particles. In dissolution, the pore space is enlarged by a fluid that gradually consumes the solid matrix. The principal goal of this research is to understand the role of the coupling between the pore space geometry and flow properties on long-time dynamical properties.This will be accomplished by constructing simplified models that capture the essence of these processes and upon which analytical calculations can be performed. The basic intellectual goal is to elucidate the role of feedback between the time evolution of the flow and the physical properties of the porous medium. In the problem of filtration, the focus will be to develop a criterion to determine the useful lifetime of a filter and to understand the kinetics of filtration due to the trapping of fine particles. In dissolution, one basic goal is to understand the role of longitudinal gradients on the basic dynamics of single tube growth. Another major goal will be to quantify the transition between homogeneous dissolution and wormhole growth as a function o the relative flow and reaction rates.%%%This award supports theoretical investigations into the structure of growing networks. The networks to be studied grow incrementally through popularity-based rules in which nodes that already have a relatively large number of attached links have a higher propensity for gaining new links. This mechanism appears to underlie a variety of networked systems, such as the world-wide web, the Internet, and various biological networks. The primary goal of this research is to develop a comprehensive quantitative understanding of network structure through the formulation and analysis of the governing rate equations for the evolution of prototypical network models.A parallel effort will be devoted to studying porous networks that evolve due to the interaction of a reactive fluid that flows through the medium. In the case of filtration, the pore space is gradually constricted, because of trapping of suspended particles. In dissolution, the pore space is enlarged by a fluid that gradually consumes the solid matrix. The principal goal of this research is to understand the role of the coupling between the pore space geometry and flow properties on long-time dynamical properties.***

0227670 Redner该奖项支持对增长网络结构的理论研究。 待研究的网络通过基于流行度的规则逐渐增长，其中已经具有相对大量附加链接的节点具有获得新链接的更高倾向。 这种机制似乎是各种网络系统的基础，例如万维网，互联网和各种生物网络。 本研究的主要目标是通过对典型网络模型演化的控制速率方程的公式化和分析，对网络结构有一个全面的定量理解。 衰减过程的作用，如删除节点或链接在一个有限的速度，对网络的完整性将进行研究。 另一个项目将专注于通过独立节点和链接创建事件增长的网络的渗透特性。 速率方程的方法也将扩展到处理蛋白质相互作用网络中的生长机制模型的基本过程的小生物有机体，如酵母和细菌。 除了研究度分布等局部网络属性外，还将致力于揭示网络内的社区结构--社区之间联系较弱的紧密联系的子网。 一个平行的努力将致力于研究多孔网络的演变，由于反应流体的相互作用，流过介质。 在过滤的情况下，由于悬浮颗粒的捕获，孔隙空间逐渐收缩。 在溶解过程中，孔隙空间被逐渐消耗固体基质的流体扩大。 本研究的主要目标是了解孔隙空间几何形状和流动特性之间的耦合作用对长时间动力学特性的影响，这将通过构建简化模型来实现，这些模型捕捉了这些过程的本质，并可以进行分析计算。 基本的智力目标是阐明流动的时间演变与多孔介质的物理性质之间的反馈作用。 在过滤问题中，重点将是制定一个标准，以确定过滤器的使用寿命，并了解由于捕获细颗粒而导致的过滤动力学。 在溶解中，一个基本目标是了解纵向梯度对单管生长的基本动力学的作用。 另一个主要目标将是量化均匀溶解和虫孔生长之间的过渡作为相对流量和反应速率的函数。该奖项支持对不断增长的网络结构的理论研究。 待研究的网络通过基于流行度的规则逐渐增长，其中已经具有相对大量附加链接的节点具有获得新链接的更高倾向。 这种机制似乎是各种网络系统的基础，例如万维网，互联网和各种生物网络。 本研究的主要目的是通过对网络模型演化的速率方程的建立和分析，对网络结构有一个全面的定量认识，同时也将致力于研究多孔网络的演化，这种演化是由于反应性流体流过介质的相互作用引起的。 在过滤的情况下，由于悬浮颗粒的捕获，孔隙空间逐渐收缩。 在溶解过程中，孔隙空间被逐渐消耗固体基质的流体扩大。 本研究的主要目标是了解孔隙空间几何形状和流动性质之间的耦合对长期动力学性质的作用。