Collaborative Research: QNATS--The Queueing Network Approximator for Time-Dependent Systems

合作研究：QNATS——瞬态系统的排队网络近似器

• 批准号: 0521945
• 负责人: Michael Taaffe
• 金额: $ 26.2万
• 依托单位: Virginia Polytechnic Institute and State University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2005
• 资助国家: 美国
• 起止时间: 2005-08-15 至 2009-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0521945&HistoricalAwards=false
• 关键词: Collaborative; Research; QNATS; Queueing; Network

This NSF grant will provide funding for the development of algorithms and supporting theory for numerical analysis and approximation of general arrival/service-process queueing networks having time-dependent input parameters, characteristics and protocols. The result will be QNATS, the Queueing Network Approximator for Time-Dependent Systems---an addition to the NSF Cyberinfrastructure of web-useable software that is available to the engineering and scientific community. QNATS will include the facility to analyze systems in which arrival and service mechanisms change with time, as well as queueing nodal capacity and the number of servers. Also considered will be deterministic additions/deletions of entities from queueing nodes as a function of time. QNATS will allow for time-dependent interarrival- and service-time distributions that are general in shape, rather than the often unrealistic time-dependent exponential/Poisson distributions of textbook models. QNATS models will be easy to build and QNATS analysis will be able to deliver results quickly enough to be used interactively via web services Queueing models are among the most widely used techniques to design and improve the performance of manufacturing, service-sector, digital-telecommunications and computer systems. In fact, queueing models are useful for assessing the performance of additions to the Cyberinfrastructure itself. Virtually any system in which discrete entities contend for resources from one or more service nodes can be represented as a network of queues. For example, time-dependent, infinite-server queueing networks have become a standard model for analysis of cellular telecommunication systems. Other applications come from a large variety of fields, including population processes in biology, migration/immigration processes, and epidemiology. QNATS will allow engineers and scientists in many fields to avoid the disastrous consequences that can occur when time-varying system characteristics are ignored or are approximated by their time-averaged values, leading to severe underestimation of system congestion.

该NSF赠款将为开发算法和支持理论提供资金，用于数值分析和一般到达/服务过程排队网络，具有时间依赖于时间依赖的输入参数，特征和协议。 结果将是Qnats，这是时间相关系统的排队网络近似器 - - 可用于工程和科学界的NSF Cyber​​infrasture的NSF Cyber​​infradstructure的补充。 QNAT将包括分析系统的设施，其中到达和服务机制随时间而变化，以及排队节点容量和服务器数量。 还考虑的是，从排队节点作为时间的函数中的实体的确定性添加/删除。 QNAT将允许与时间相关的时间内和服务时间分布，而不是经常不切实际的时间依赖时间的指数/泊松分布。 QNATS模型将易于构建，QNATS分析将能够足够快地提供结果，以通过Web Services排队模型进行交互式使用，这是设计和改善制造业，服务领域，数字通信和计算机系统的最广泛使用的技术之一。 实际上，排队模型对于评估网络基础结构本身的增加非常有用。实际上，从一个或多个服务节点竞争资源的离散实体可以表示为排队网络的任何系统。 例如，时间依赖性的无限服务队列网络已成为分析细胞电信系统的标准模型。 其他应用来自各种领域，包括生物学，移民/移民过程和流行病学的人口过程。 QNAT将允许许多领域的工程师和科学家避免在随时间变化的系统特征被忽略或被其时间平均值近似时可能发生的灾难性后果，从而导致系统拥塞的严重低估。