Query Processing Over GIS Objects With Functional Attributes

具有功能属性的 GIS 对象的查询处理

• 批准号: 0534781
• 负责人: Vassilis Tsotras
• 金额: --
• 依托单位: University of California-Riverside
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2006
• 资助国家: 美国
• 起止时间: 2006-08-15 至 2010-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0534781&HistoricalAwards=false
• 关键词: Query; Processing; Over; GIS; Objects

The goal of this project is to provide efficient techniques for querying objects in geographic information systems (GIS) with "functional" attributes. Emerging GIS applications (e.g., transportation networks, traffic management, meteorological, sensor-based surveillance, mobile services) involve objects that employ one or more functional attributes. These attributes are typically functions of time and/or space (e.g., vehicle speed, precipitation, traffic flow etc.) The importance of functional attributes has been recently recognized by GIS users (especially researchers) as well as developers; however, their support is still primitive. Functional attributes drastically affect query processing speed, as they are typically computationally intensive and the query performance is based on the efficient evaluation of the attribute functions. Novel methods and solutions are thus needed. While functions can be very complex, this study concentrates on functions described (and thus stored) in constant space (e.g., polynomials of constant degree). Solutions to various query variations are proposed (aggregations, selections, joins, nearest neighbors, etc.) while both historical and predictive queries are examined. The approach taken consists of maintaining specialized indices that incrementally compute query results. A prototype that serves as a toolbox of efficient techniques for processing complex objects is also created. The results of this research will improve querying capabilities for the many applications that contain objects with functional attributes, including meteorological, geospatial, cellular, demographic, social, surveillance and traffic management environments, to name a few. The prototype will be available for use by researchers and students via the project Web site (http://www.cs.ucr.edu/~tsotras/functional.html). Course materials using this prototype will be developed as well. Through an existing collaboration with a GIS vendor, the results of this project have the potential to enhance the implementation of future GIS systems.

这个项目的目标是提供有效的技术，查询对象在地理信息系统（GIS）与“功能”属性。新兴的地理信息系统应用（例如，运输网络、交通管理、气象、基于传感器的监视、移动的服务）涉及采用一个或多个功能属性的对象。这些属性通常是时间和/或空间的函数（例如，车速、降水量、交通流量等）功能属性的重要性最近已被GIS用户（特别是研究人员）以及开发人员认识到，然而，他们的支持仍然是原始的。函数属性极大地影响查询处理速度，因为它们通常是计算密集型的，并且查询性能基于对属性函数的有效评估。因此，需要新的方法和解决方案。虽然函数可能非常复杂，但本研究集中在常数空间中描述（并因此存储）的函数（例如，常次数多项式）。提出了各种查询变体的解决方案（聚合、选择、连接、最近邻等）。同时检查历史查询和预测查询。所采取的方法包括维护专门的索引，增量计算查询结果。还创建了一个原型，作为一个工具箱的有效技术处理复杂的对象。这项研究的结果将提高查询能力的许多应用程序，包含具有功能属性的对象，包括气象，地理空间，蜂窝，人口，社会，监控和交通管理环境，仅举几例。研究人员和学生可通过项目网址（http：//www.cs.ucr.edu/functional.html）使用原型。还将开发使用这一原型的课程材料。通过与地理信息系统供应商的现有合作，该项目的成果有可能加强未来地理信息系统的实施。