Communication’s Role in Safety Management and Performance for the Road Safety Practices

Communication among organizations could play an important role in increasing road safety.To get in-depth knowledge of its role,this study measured managers’and employees’perceptions of the communication’s role on six safety management and performance criteria for road safety practices by conducting a survey using a questionnaire among 165 employees and 135 managers.Path analysis using AMOS-19 software shows that some of the safety management road safety practices have high correlation with the safety performance,namely,from the six antecedents,only the safety training and safety promotion,closely correlate with the safety motivation,and only safety commitment,safety communication and feedback have close relations with the safety knowledge and safety behavior compliance,and only safety feedback has effective relations with the safety participation.Safety feedback is identified as the most important safety management issue to road safety practices and it would predict the level of safety knowledge,safety motivation,safety compliance and safety participation.The results of this study would help the concerned agencies/orgaizations in improving their ability to assess the road safety indicators and to the future development of the safety performance management for road safety practices in these agencies.

BLE Mesh： A Practical Mesh Networking Development Framework for Public Safety Communications

Owing to advanced storage and communication capabilities today, smart devices have become the basic interface between individuals and their surrounding environment. In particular, massive devices connect to one other directly in a proximity area, thereby enabling abundant Proximity Services（Pro Se）, which can be classified into two categories： public safety communication and social discovery. However, two challenges impede the quick development and deployment of Pro Se applications. From the viewpoint of networking, no multi-hop connectivity functionality component can be directly operated on commercially off-the-shelf devices, and from the programming viewpoint, an easily reusable development framework is lacking for developers with minimal knowledge of the underlying communication technologies and connectivity. Considering these two issues, this paper makes a twofold contribution. First, a multi-hop mesh networking based on Bluetooth Low Energy（BLE） is implemented,in which a proactive routing mechanism with link-quality（i.e., received signal strength indication） assistance is designed. Second, a Pro Se development framework called BLE Mesh is designed and implemented, which can provide significant benefits for application developers, framework maintenance professionals, and end users. Rich application programming interfaces can help developers to build Pro Se apps easily and quickly. Dependency inversion principle and template method pattern allow modules in BLE Mesh to be loosely coupled and easy to maintain and update. Callback mechanism enables modules to work smoothly together and automation processes such as registration, node discovery, and messaging are employed to offer nearly zero-configuration for end users.Finally, based on the designed Pro Se development kit, a public safety communications app called Quote Send App is built to distribute emergency information in close area without Internet access. The process illustrates the easy usability of BLE Mesh to develop Pro Se apps.

Formal verification of safety protocol in train control system

In order to satisfy the safety-critical requirements,the train control system(TCS) often employs a layered safety communication protocol to provide reliable services.However,both description and verification of the safety protocols may be formidable due to the system complexity.In this paper,interface automata(IA) are used to describe the safety service interface behaviors of safety communication protocol.A formal verification method is proposed to describe the safety communication protocols using IA and translate IA model into PROMELA model so that the protocols can be verified by the model checker SPIN.A case study of using this method to describe and verify a safety communication protocol is included.The verification results illustrate that the proposed method is effective to describe the safety protocols and verify deadlocks,livelocks and several mandatory consistency properties.A prototype of safety protocols is also developed based on the presented formally verifying method.