Sylwia Werbińska-Wojciechowska

Exact and approximation methods for dependability assessment of tram systems with time window

The transportation system examined in this paper is the city tram one, where failed trams are replaced by reliable spare ones. If failed tram is repaired and delivered, then it comes back on work. There is the time window that failed tram has to be either replaced (exchanged) by spare or by repaired and delivered within. Time window is therefore paramount to user perception of transport system unreliability. Time between two subsequent failures, exchange time, and repair together with delivery time, respectively, are described by random variables A, E, and D. A/E/D is selected as the notation for these random variables. There is a finite number of spare trams. Delivery time does not depend on the number of repair facilities. Hence, repair and delivery process can be treated as one with infinite number of facilities. Undesirable event called hazard is the event: neither the replacement nor the delivery has been completed in the time window. The goal of the paper is to find the following relationships: hazard probability of the tram system and mean hazard time as functions of number of spare trams. For systems with exponential time between failures, Weibull exchange and exponential delivery (so M/W/M in the proposed notation) two accurate solutions have been found. For systems with Weibull time between failures with shape in the range from 0.9 to 1.1, Weibull exchange and exponential delivery (i.e. W/W/M) a method yielding small errors has been provided. For the most general and difficult case in which all the random variables conform to Weibull distribution (W/W/W) a method returning moderate errors has been given.

Maintenance Decision Making Process – A Case Study of Passenger Transportation Company

In the presented paper, the authors’ research work is focused on the analysis of maintenance decision making process performance with taking into account necessary operational data availability. Thus, in the Introduction section, the transportation systems maintenance issues are described. Later, there is a comprehensive literature overview in the analysed research area provided. This gives the possibility to present the decision making process in the transportation systems’ maintenance management area. Later, in the next Section, the case study for maintenance management processes performance in chosen passenger transportation company is investigated. Following this, the computer systems used for operational data gathering are characterised, and the data availability is investigated.

The Scope of the Collected Data for a Holistic Risk Assessment Performance in the Road Freight Transport Companies

In the presented paper, authors focus on the issues connected with passenger transportation companies risk assessment. Following this, in the article the authors investigate the problem of information needs that make possible a full risk analysis performance for freight transport companies. Thus, the holistic approach in risk assessment for road transport companies is discussed. Later, there is presented a short literature review connected with information systems dedicated for risk management performance. This gives the possibility to define the main data reporting system that meets the requirements of risk assessment performance. Article ends with some conclusions and directions for future research.

Risk assessment issues in the process of freight transport performance

Abstract In the presented paper, authors focus on the issues related to risk assessment of transport processes performance. Thus, there are presented the basic definitions related to the research area. Later, there is discussed the possibility of risk assessment performance in the freight transport, outlining an assessment approach compatible with ISO 31000 standard and ERM concept. This gives the possibility for the presentation of risk assessment of transport processes performance in the chosen road transport company. The article concludes with a summary, including directions for further research.

Reliability Assessment of Production Process – Markov Modelling Approach

In the presented paper, authors focus on the issues connected with production processes reliability assessment. Such analyses regard considering many different factors and requirements. Thus, based on the developed multidimensional definition of production process reliability, the seven-state Markov model of production process performance is presented. Later, there is provided a comprehensive sensitivity analysis of the developed model based on the expert opinions in the area of model parameters estimation. The work ends up with summary and directions for further research.

ISO 55001 and difficulties of its implementation in polish enterprises

Abstract In the presented paper, authors focus on the issues related to asset management in enterprises. The aim of the article is to present the requirements and standards defined in ISO 55001. Thus, there are presented the basic definitions related to the research area. Later, there are discussed the main guidelines set out in the standard, with taking into consideration e.g. asset management system structure. Moreover, there are defined the basic procedural steps in the process of ISO 55001 standard implementation in enterprises. This gives the possibility for the analysis of ISO 55001 standard possibilities of implementation in Polish enterprises. The article concludes with a summary.

Assessment methods of production processes reliability – state of the art

Abstract In the paper, authors focus on a problem of reliable performance of production processes. Reliability analyses of production systems regard considering many different factors and requirements. As a result, the paper discusses the basic definitions from the area of production engineering and reliability theory. Based on the literature research, there is proposed a basic classification of methods for production processes reliability assessment. Later, authors focus on the development of a multidimensional approach to production process reliability assessment. The work ends up with summary and directions for further research.

Vulnerability of Passenger Transportation System—The Main Information Provided by Key Stakeholders. Case Study

In the presented paper, authors focus on the issues connected with passenger transportation system vulnerability assessment. Following this, in the article the authors investigate the problem of information needs that make possible a full risk analysis performance for municipal transport system. Thus, there is presented a short literature review connected with assessment methods used in the analysed research area. There are also defined the main definitions. This gives the possibility to define the main information system that meets of vulnerability performance. There is also given an analysis aimed at investigation of potential use of vulnerability analysis results by public transport stakeholders. Article ends with some conclusions and directions for future research.

Influence of Data Uncertainty on the Optimum Inspection Period in a Multi-unit System Maintained According to the Block Inspection Policy

In the presented paper, authors focus on delay-time-based maintenance modelling issues. They present an analytical maintenance model for multi-unit systems. Implemented maintenance policy is the Block-Inspection Policy (BIP) that assumes performing inspection actions at regular time intervals of T. In the next step, the problem of data uncertainty is analysed. There is also investigated the sensitivity analysis of the proposed cost model due to probability distributions of system elements’ initial and delay times parameters change.

Issues on Vulnerability of Passenger Transportation System

Abstract In the presented paper, authors focus on the issues connected with passenger transportation system vulnerability assessment. Following this, in the article the main transportation system vulnerability definitions are discussed. Later, there is presented the comprehensive literature review connected with assessment methods used in the analysed research area. This gives the possibility to define the public transportation system’s vulnerability assessment as an element of process controlling performed by a carrier. Article ends with some conclusions and directions for future research.