Tomasz Ciszewski

Assessment of the Safety of Microprocessor-Based Semi-automatic Block Signalling System

Qualitative assessment of the railway traffic control system is necessary to ensure railway traffic safety. According to CENELEC standards all railway applications are obliged to conduct RAMS (reliability, availability, maintainability and safety) analysis. This process should include the actions associated with design, production, installation, verification, as well as validation and the acceptance of the system. In this paper a safety analysis for the microprocessor-based semi-automatic block signalling was described. Provided analysis allows stating, if the risk is acceptable (and so further analysis is not necessary). If not, then additional protection measures should be implemented in order to keep the hazard and associated risk at an acceptable level. Methodology accepted in this analysis can be used for the evaluation of safety factors for other electronic railway traffic control systems.

Renovation of Marine Telematics Objects in the Process of Exploitation.

Constant deterioration of the technical condition of maritime objects implies the necessity of their maintenance and renovation. The paper is concerned with issues regarding the maintenance and repair of maritime objects and modelling the renovation action for them. Presented analysis will take into account complex aspects of the operation process. The maintenance and renovation restore, in particular, the reliability and capability of maritime objects. The operation process of maritime objects will be presented in a two-dimensional aspect. It means that the analysis will include changes in both the technical and operational states of maritime objects which are interdependent.

The Concept of Railway Traffic Control Systems Remote Diagnostic

The development of railway traffic control systems gives the new opportunities for remote diagnostics and events logging in the maintenance and diagnostics centres. This possibility is a result of use the information technology in modern systems. Despite the steady technological progress, there is the lack of common methods of acquiring diagnostic data, both in terms of the scope of collected data and the manner of their presentation. This results in the use of variety solutions by individual producers operating on the market. The authors of the article inspired by the Simple Network Management Protocol (SNMP) proposed the use of this network standard in the diagnostics of railway traffic control systems. Since the research are in the initial stage only Level Crossing Protection Systems are included in the study. For this study two Management Information Bases (MIB) were developed. In the first base SNMP traps, sent by the SNMP agent, are defined. The second one defines the scope of data that can be a part of the polling by management station. In the next step the authors developed the SNMP client software. This software allows you to change parameters of Level Crossing Protection Systems and makes them available at the request of the SNMP manager. In SNMP client software the possibility of sending information about the system faults in the form of SNMP traps are implemented. The conducted study have confirmed the usefulness of SNMP technology in the railway traffic control system diagnostics. There is also the need to extend the research to other devices and systems.

Failure Evaluation of the Level Crossing Protection System Based on Fault Tree Analysis

An intersection where railway line crosses a road at the same level is called level crossing. The development of the automotive industry has resulted in an increase in the number of vehicles. Thus the traffic on the level crossings has been raised and this, in turn, has resulted in an increase requirements in terms of level crossings safety. For this purpose, the Level Crossing Protection Systems (LCPS), that help to protect these road users, are built. LCPS systems, due to the need to ensure the efficient operating of the railway, should be developed taking into account the detailed analyses. It is necessary to include in these analyses the growing needs and expectations of users in terms of system functionality. However, the requirements for ensuring the reliability and safety of systems should be taken into consideration above all. One of the methods to identify and analyse the factors which may cause adverse events is the Fault Tree Analysis (FTA). The authors of this article using the FTA method carried out a qualitative analysis of the safety of B class level crossings. Traffic safety related requirements for LCPS system were described. Then this analysis was used to identify top and intermediate events and build necessary fault trees. Conducted analysis may be helpful in the process of designing new LCPS systems.