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Modern manufacturing systems are expected to be flexible and efficient in order to cope with challenging market demands. Thus, they must be flexible enough as to meet changing requirements such as changes in production, energy efficiency, performance optimization, fault tolerance to process or controller faults, among others. Demanding requirements can be defined as a set of quality of service (QoS) requirements to be met. This paper proposes a generic and customizable multi-agent architecture that, making use of distributed agents, monitors QoS, triggering, if needed, a reconfiguration of the control system to recover QoS. As a proof of concept, the architecture has been implemented to provide availability of the control system understood as service continuity. The prototype has been tested in a case study consisting of an assembly cell where assessment of the approach has been conducted. [ABSTRACT FROM AUTHOR]

The current approach in practice to produce the flowshop schedules of precast production is the dispatching rule technique, which does not guarantee optimal schedules. Some researchers have developed models for a single production line to optimize the scheduling, in which Genetic Algorithm (GA) is used to obtain the solution. However the models cannot be used for multiple production lines. Moreover, some optimization constraints and objectives were missing in the models, such as avoiding frequent type change of precast components during production. Both issues hinder their work to be applied to real precast plants. To overcome the problem, this paper proposes a Flowshop Scheduling Model of Multiple production lines for Precast production (MP-FSM) and develops a corresponding optimization approach to facilitate optimized scheduling by using GA. The approach was validated preliminarily by comparing with traditional scheduling approaches. The results demonstrated that optimized schedules can be obtained by using the proposed approach. [ABSTRACT FROM AUTHOR]

In order to improve the accuracy of productivity calculation and prediction, this paper aims to establish a mathematical model, which takes multi-factor revision into account, to evaluate the personnel operational capacity (POC) of aircraft assembly lines. Firstly, the assembly operation is divided into assembly operating elements (AOEs), which is based on the features of aircraft assembling and is for the provision of statistical units. Secondly, effective man-hour (EMH) is adopted as a yardstick to measure the POC. Then, considering the technical characteristics and environmental constraints of the real assembly line, detailed quantitative descriptions about the chosen key factors, namely assembling accuracy, learning effect, and assembling intensity, are provided, and these quantitative descriptions are used for the revision of the EMH in order to guarantee a higher precision. After that, several critical parameters such as the cycle time, tact time, and output of an assembly line can be solved out, from which the POC can be analyzed and reflected. Finally, this method has been successfully applied to a practical case, and the result justifies its advantage as well as feasibility. [ABSTRACT FROM AUTHOR]