Fast Search for Dynamic Multi-Relational Graphs

Acting on time-critical events by processing ever growing social media or news streams is a major technical challenge. Many of these data sources can be modeled as multi-relational graphs. Continuous queries or techniques to search for rare events that typically arise in monitoring applications have been studied extensively for relational databases. This work is dedicated to answer the question that emerges naturally: how can we efficiently execute a continuous query on a dynamic graph? This paper presents an exact subgraph search algorithm that exploits the temporal characteristics of representative queries for online news or social media monitoring. The algorithm is based on a novel data structure called the Subgraph Join Tree (SJ-Tree) that leverages the structural and semantic characteristics of the underlying multi-relational graph. The paper concludes with extensive experimentation on several real-world datasets that demonstrates the validity of this approach.Comment: SIGMOD Workshop on Dynamic Networks Management and Mining (DyNetMM), 201

A Selectivity based approach to Continuous Pattern Detection in Streaming Graphs

Cyber security is one of the most significant technical challenges in current times. Detecting adversarial activities, prevention of theft of intellectual properties and customer data is a high priority for corporations and government agencies around the world. Cyber defenders need to analyze massive-scale, high-resolution network flows to identify, categorize, and mitigate attacks involving networks spanning institutional and national boundaries. Many of the cyber attacks can be described as subgraph patterns, with prominent examples being insider infiltrations (path queries), denial of service (parallel paths) and malicious spreads (tree queries). This motivates us to explore subgraph matching on streaming graphs in a continuous setting. The novelty of our work lies in using the subgraph distributional statistics collected from the streaming graph to determine the query processing strategy. We introduce a "Lazy Search" algorithm where the search strategy is decided on a vertex-to-vertex basis depending on the likelihood of a match in the vertex neighborhood. We also propose a metric named "Relative Selectivity" that is used to select between different query processing strategies. Our experiments performed on real online news, network traffic stream and a synthetic social network benchmark demonstrate 10-100x speedups over selectivity agnostic approaches.Comment: in 18th International Conference on Extending Database Technology (EDBT) (2015

A Novel Multithreaded Algorithm for Extracting Maximal Chordal Subgraphs

Chordal graphs are triangulated graphs where any cycle larger than three is bisected by a chord. Many combinatorial optimization problems such as computing the size of the maximum clique and the chromatic number are NP-hard on general graphs but have polynomial time solutions on chordal graphs. In this paper, we present a novel multithreaded algorithm to extract a maximal chordal sub graph from a general graph. We develop an iterative approach where each thread can asynchronously update a subset of edges that are dynamically assigned to it per iteration and implement our algorithm on two different multithreaded architectures - Cray XMT, a massively multithreaded platform, and AMD Magny-Cours, a shared memory multicore platform. In addition to the proof of correctness, we present the performance of our algorithm using a test set of synthetical graphs with up to half-a-billion edges and real world networks from gene correlation studies and demonstrate that our algorithm achieves high scalability for all inputs on both types of architectures

Elaboración del documento de seguimiento y evaluación como elemento estructurante de la revisión y ajuste del esquema de ordenamiento territorial del Municipio de Albán, Cundinamarca

El ordenamiento territorial en Colombia surge como una nueva función de las entidades municipales enfocada en la descentralización y autonomía administrativa. Este instrumento además de su ejecución por parte de las administraciones en el corto, mediano y largo plazo, debe ser sometido a una revisión de acuerdo al artículo 28 de la Ley 388 de 1997 y lo que expresa el artículo 5 del Decreto 4002 de 2004. De esta manera se hace el seguimiento y evaluación del Esquema de Ordenamiento Territorial del municipio de Albán, Cundinamarca, que se realiza en el marco de vencimiento de términos del actual EOT adoptado por Acuerdo municipal No. 14 de 2000. Por lo tanto se efectúa la revisión de los contenidos del EOT evidenciando que estos cumplieran con los requerimientos de la Ley 388 de 1997 y el Decreto 879 de 1998. Por otro lado se evaluó el nivel de articulación que existía entre la visión y objetivos, denominados fines; y las estrategias y proyectos, denominados medios; para alcanzar el modelo territorial, lograr el cumplimiento de objetivos y del modelo de ejecución propuesto.Land management in Colombia appears as a new function of the government institutions focused on the administrative decentralization and autonomy. These institutions use this political way on short, medium and long terms. This has to be checked according to the article 28 of the Law 388 established in 1997 and as it is showed by the article 5 of the Decree 4002. In this manner, the Alban’s Cundinamarca Land Planning Framework due the terms adopted by the current Land Planning Framework adapted by the Municipal Resolution N. 14 of 2000 is tracked and evaluated. Therefore, the Land Planning Framework’s content evaluation is accomplished, showing how they fulfill the Law and Decree’s requirements. It also shows a sufficiency’s analysis to evaluate if these items are coherent and sufficient according to the formulated model. On the other hand, the level of articulation between the vision and the objectives denominated purposes and strategies and projects as methods has been evaluated. In addition, the Land Planning Framework’s performance was appreciated and presented by tracker’s parameters and indicators to identify if the LandUse Planning projects have been executed to achieve the land model, the objective achievements and th budget’s execution

Standards for Graph Algorithm Primitives

It is our view that the state of the art in constructing a large collection of graph algorithms in terms of linear algebraic operations is mature enough to support the emergence of a standard set of primitive building blocks. This paper is a position paper defining the problem and announcing our intention to launch an open effort to define this standard.Comment: 2 pages, IEEE HPEC 201