Control problems in manufacturing and communication networks

点击翻译按钮获取中文摘要

The control of complex interconnected systems such as manufacturing and communication networks presents important conceptual and computational challenges. Approximate system decomposition is one way of partially mitigating these challenges. The researcher and coworkers, have recently developed  a decomposition method for  transfer lines in manufacturing  which permits new structural insights and greatly simplifies the important associated optimal buffer sizing problems. It is proposed to extend this decomposition method in two important directions by considering:   First, production control architectures more general than Kanbans ( for which each transfer line machine is associated with a fixed buffer that it must attempt to fill), such as CONWIP, i.e. CONstant Work In Process (the kanban strategy is applied to a string of machines), or generalized kanbans (desynchronizing actual production from migration of production authorization); second, multi-part (versus single part) type systems, as they constitute the bulk of capital intensive flexible manufacturing systems. The know how developed in solving these manufacturing system problems is to be transferred in order to help address related quality of service (QoS) assurance issues in next generation communication networks (Internet and wireless systems interconnected to offer Internet like services with performance guarantees). Indeed, fixed Internet routes strongly resemble transfer lines, and performance analysis  within the so-called DIFFSERV paradigm (aggregating Internet traffics into a small number of differentiated QoS classes for scalability) is closely related to performance analysis of  multi-part type transfer lines in manufacturing. Finally, it has been observed that fluid approximations can yield interesting insights and acceptable numerical accuracy in analyzing discrete manufacturing processes. Using fluid approximations of wireless data transmission processes, we propose to further explore the potential of the well established (continuous) linear regulator theory in deriving tractable schedules with the right mix of fairness and efficiency.