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The traditional research on scheduling focuses on task scheduling and schedulability analysis in concurrent reactive systems. In this article, we dedicate ourselves to event-based scheduling. We first formally define an event-based scheduling policy and propose the notion of the correctness of a scheduling policy in terms of weak termination. Then we investigate the correctness of the decomposition of scheduling controls and finally obtain a decentralized scheduling method. The method can automatically decompose the scheduling policies of a concurrent reactive system into atomic scheduling policies. Every atomic scheduling policy corresponds to one subsystem. Each of the subsystems is a completely independent system, which may be developed and deployed independently. An experiment demonstrates these results that may help engineers to design correct and efficient schedule policies for a concurrent reactive system.

In the field of intelligent connected vehicles, as the rate of in-vehicle communication continues to increase, the importance of real-time and reliability requirements has been more prominent. The time-sensitive networking (TSN) task group is dedicated to the amendments for meeting the urgent needs in the industrial field. In the implementation of the TSN, time latency bounds of critical traffic, memory bounds of nodes and utilization of transmission resources are needed to evaluate the feasibility of the TSNs. In this paper, we propose a framework called component-based analysis (CBA) to analyze these properties. In CBA, we use a data model, a resource model, and a component model to construct an abstract model of the TSNs with the system architecture and analyze the feasibility of this abstract model with real-time calculus. Moreover, we discuss the preemption mechanism mentioned in IEEE 802.1Qbu to handle the conflict of different priority queues, which has a serious influence on the resource model of the TSNs. Finally, we validate this framework by performing an analysis on a synthetic case and compare the obtained properties with different conflict handling mechanisms. INDEX TERMS TSN, component-based analysis, real-time calculus, feasibility.The associate editor coordinating the review of this manuscript and approving it for publication was Yulei Wu. FIGURE 1. On-board network topology example. communication protocols, including the Real-time Transport Protocol [2] (RTP) and Audio Video Bridging [3] (AVB), have been developed, but the complexity of these protocols

Mobility is a critical issue that must be considered during the modeling and analyzing of a mobile system. At a high abstract level, event-based models can directly specify a mobile system without the introduction of additional mechanisms. In this article, we first propose two types of special events, entering and exiting an ambient, as movement events. Next, based on the movement events, we introduce the notion of a movement path and propose a feasible movement criterion (deciding whether a given movement path of a mobile object (agent) is feasible or not in terms of spatiotemporal topological relationships of ambients). Then, we investigate how a message movement--based communication model represents synchronous communication, asynchronous communication, and broadcast communication in a unified way. Finally, we use movement event sequences to discuss the exclusivity of ambients (an ambient only allows one mobile object to occupy (enter) it at any moment) and show that a priority scheduling control policy can guarantee exclusivity. Accordingly, we propose a correct movement criterion—that is, a correct movement path is feasible and satisfies the exclusivity of ambients. Case studies demonstrate these results.

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