RII Track-4:NSF: DyG-MAP: Fast Algorithms for Mining and Analysis of Evolving Patterns in Large Dynamic Graphs

图（网络）是一个通用的科学框架，用于表示和分析生物、社会和人类制造的复杂系统。这种复杂的系统本质上是动态的——例如，社会互动和人类活动是间歇性的；连接在功能性大脑网络中出现和消失。尽管“时间”在这些系统中扮演着核心角色，但大多数关于图的经典研究都是基于静态图（不随时间变化的图）的拓扑特性。现有的关于动态图的研究表明，对于大规模的实际数据集，其可扩展性有限。本研究旨在通过开发创新的算法和计算技术，设计快速、可扩展的方法来揭示社会技术系统的动态行为。主办地点伯克利实验室将提供独特的专业知识和指导，并促进访问领先的超级计算机设施，以实现拟议的研究目标。该项目将产生新的算法技术和可扩展的软件工具，以推进基于图形的数据科学和高性能科学计算。在这项研究中，PI包括一名代表性不足的研究生。还将根据该项目产生的技术和成果为PI机构开发教育和培训模块。因此，该项目将提高PI辖区的科研、培训和教育能力。EPSCoR提案的目标是开发快速和可扩展的方法来挖掘和分析大型动态图。这类图的例子包括社交网络、人际接触网络、网络图和功能性大脑网络。该提案解决了基于子结构的问题，如寻找进化的社区和枚举有趣的时间子图或基序，应用于神经科学、生物信息学、基础设施和社会领域。尽管关于静态图的文献非常丰富，但是关于动态图的文献却非常少。现有的动态图并行算法由于其计算与内存操作的比例较低和不规则的内存访问模式而表现出有限的可扩展性。因此，这种算法表现出较弱的时空局部性，导致缓存利用率低，通信量大。拟议的研究将利用与伯克利实验室性能和算法组的独特合作，利用最先进的用户设施和领先的专业知识来解决上述技术挑战。该提案旨在开发具有有效负载平衡和通信避免技术的可扩展并行方法，具有采样和稀疏化的数据减少方法，以及时间度量的有效形式化。由该提案产生的算法方法将适用于理解各种现实世界系统的动态特性，例如，定位皮质（大脑）网络中的关键神经元，基础设施网络中时变流量的路由规划，疾病/病毒建模或社会/接触网络中的信息传播。因此，该项目将扩大PI的研究能力，以建立有影响力的软件/技术工具，并提高他作为研究导师和教育工作者为东道国不同学生群体服务的能力。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

Graphs (networks) are a versatile scientific framework to represent and analyze biological, social, and human-made complex systems. Such complex systems are inherently dynamic—for example, social interactions and human activities are intermittent; links appear and disappear in functional brain networks. Despite “time” playing a central role in those systems, most of the classic studies on graphs are based on the topological properties of static graphs (graphs that do not change over time). The existing works on dynamic graphs show only limited scalability for large-scale practical datasets. This proposed research aims at designing fast, scalable methods for revealing dynamic behaviors of a socio-technical system by developing innovative algorithmic and computing techniques. The host site, Berkeley Lab, will provide unique expertise and mentoring and facilitate access to leading supercomputer facilities to achieve the proposed research goals. The project will generate new algorithmic techniques and scalable software tools to advance graph-based data science and high-performance scientific computing. The PI includes an underrepresented graduate student in this research. Educational and training modules will also be developed for PI’s institution from the techniques and results emerging from this project. Thus, the project will enhance the scientific research, training, and education capacity of the PI’s jurisdiction.The goal of this EPSCoR proposal is to develop fast and scalable methods for mining and analyzing large dynamic graphs. Examples of such graphs include social networks, human contact networks, web graphs, and functional brain networks. The proposal addresses substructure-based problems such as finding evolving communities and enumerating interesting temporal subgraphs or motifs with applications in neuroscience, bioinformatics, infrastructure, and social domains. Even though there exists a rich literature for static graphs, the literature for dynamic graphs is very nascent. Existing parallel algorithms for dynamic graphs demonstrate limited scalability due to their low ratio of compute to memory operations and the irregular memory access patterns. Consequently, such algorithms show weak spatial and temporal locality, leading to poor cache utilization and high communication volume. The proposed research will utilize a unique collaboration with the Performance and Algorithms Group of Berkeley Lab to avail the most advanced user facilities and leading expertise to tackle the above technical challenges. The proposal aims at developing scalable parallel methods with efficient load-balancing and communication-avoidance techniques, data reduction approaches with sampling and sparsification, and efficient formalization of temporal metrics. Algorithmic methods generated from this proposal will be applicable in understanding dynamic properties of various real-world systems—for instance, locating key neurons in cortical (brain) networks, route-planning for time-varying traffic in infrastructure networks, modeling disease/virus or information propagation in social/contact networks. Therefore, the project will expand the PI’s research capacity to build impactful software/technology tools and also enhance his ability to serve a diverse student population at his host institution as both a research mentor and an educator.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.