Every critical online unit in a continuous process must always function normally, and one or more identical units are usually put on standby to sustain the uninterrupted operation. Although a few related studies have been reported in the literature, a comprehensive analysis of the standby mechanism still has not been carried out. The objective of this research is to construct a generalized mathematical model to synthesize the multilayer standby mechanisms for any given processes by minimizing the total expected life cycle expenditure. A Matlab code can be developed accordingly to perform the required optimization tasks via a genetic algorithm. The feasibility and effectiveness of the proposed approach have been demonstrated with the case studies concerning the pump system in a typical chemical plant. From the optimization results, one can obtain the optimal design specifications of the multilayer standby mechanism, which include (1) the number of layers, (2) the numbers of both online and spare sensors in each measurement channel, (3) the corresponding voting-gate logic in each channel, (4) the inspection interval of a switch, (5) the number of spares for a switch, (6) the inspection intervals for warm standbys, and (7) the number of cold standbys.

中文翻译：

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连续化学过程中多层待机机制的优化

连续过程中的每个关键在线单元必须始终正常运行，并且通常将一个或多个相同的单元置于备用状态以维持不间断的运行。尽管文献中已经报道了一些相关研究，但是仍未对待机机制进行全面分析。这项研究的目的是构建一个通用的数学模型，以通过使总预期寿命周期支出最小化来为任何给定过程综合多层备用机制。可以相应地开发Matlab代码，以通过遗传算法执行所需的优化任务。通过与典型化工厂中的泵系统有关的案例研究，证明了该方法的可行性和有效性。根据优化结果，