In a networked discrete event system, communication between a plant and a supervisor/agent is carried out via a wired/wireless communication network, in which communication delays are unavoidable. Hence, how to obtain state estimates under communication delays is an important problem. The existing methods assume that there is only one communication channel and, thus, the first-in, first-out (FIFO) property is satisfied. In complex systems distributed over several locations, several channels are often used to send the event occurrences to the (central) supervisor/agent, in which the FIFO property holds only for each channel and communication delays may be different for different channels. To address these new challenges, this paper investigates the state estimation problem in multichannel networked discrete event systems. Two methods are proposed. The first method is relatively simpler and computes only conservative estimates. The second method is more complex, but it computes the exact state estimates. Examples are given to illustrate the results.

中文翻译：

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多通道网络离散事件系统的状态估计

在联网的离散事件系统中，工厂与主管/座席之间的通信是通过有线/无线通信网络进行的，在该通信网络中，通信延迟是不可避免的。因此，如何获得通信延迟下的状态估计是一个重要的问题。现有方法假定只有一个通信通道，因此满足先进先出（FIFO）属性。在分布在多个位置的复杂系统中，通常使用多个通道将事件发生发送到（中央）主管/代理，其中FIFO属性仅适用于每个通道，并且通信延迟对于不同的通道可能有所不同。为了应对这些新挑战，本文研究了多通道网络离散事件系统中的状态估计问题。提出了两种方法。第一种方法相对简单，仅计算保守估计。第二种方法更复杂，但是它可以计算精确的状态估计。举例说明结果。