Berg Heinz-Peter, Volkanovski Andrija
Ageing PSA as a support for effective ageing management
Because of the growing operational age of nuclear power plants, the ageing management of structures, systems and components used in these plants is gaining an important role. Technical systems are subject to timedependent and operationally caused ageing phenomena with modifications of originally given characteristics and, thus, of relevance in terms of safety. Especially physical ageing is of importance. Therefore, a comprehensive ageing management is required. In the context of an integrated safety management it has to be shown how to integrate the safety related issues of ageing into probabilistic safety assessment (PSA). In particular the question is to be answered whether the effort for the execution of an ageing PSA is justified, in particular if the safety significant effects of ageing can be identified and quantitatively estimated. Method for prioritization of the components in the nuclear power plant considering implication of their ageing on safety of the nuclear power plant is presented. On the basis of an actual report on ageing management in German nuclear power plants and a literature survey, this paper tries to estimate the necessity and value for the introduction of an ageing PSA in Germany. [full text]
Boryczko Krzysztof, Rak Janusz, Tchórzewska-Cieślak Barbara
Analysis of risk and failure scenarios in water supply system
Water supply system is complicated technical system which belongs to underground urban infrastructure. Its accurate functioning determines everyday live stability of citizens. Risk analysis is a key phase of the process of water supply safety management. The aim of this paper is to present new propose of methods for risk of the first type (associated with quantity of supplied water) and the risk of the second type (associated with quality of supplied water) analyses in water supply system. The paper contains the description of matrix methods for risk analyses and methods describing cause-and-effect relationship of failure events (fault tree analysis). [full text]
Chlebus Maciej
The problem of assessing risk in the supply chain of a logistics process
Process of suppliers selection, as well as cooperation between suppliers and manufacturers, are a significant problem for today’s companies. Producers negotiate and arrange with their subcontractors to ensure a continuity of production. Following this, one of the major problem is supplier evaluation and supply risk assessment in order to avoid delays, which may seriously affect the producers’ ability.
In the paper there are presented the main types of risk and the methods of its classification and evaluation used in logistic processes performance. The analysed problem is to be discussed on the example of Whirlpool-Polar company from Poland. For the presented company, there is investigated supplier evaluation process, suppliers classification with the relation of their purchasing and bargaining power to the degree of their obligations fulfilment. Moreover, there is defined the supply risk concept, what gives the possibility to compare the suppliers purchasing power with the defined supply risk. Later, there are presented main possibilities to reduce the supply risk by using a “milk run” method with a number of variants of the simulation and its evaluations.The presented results comply with the profitability of transport in the case of round-trip transportationperformance. Transport of goods is cost effective when the usage of the truck transport capacity will be at least85%. Following this, the presented research analysis result gives the possibility to reduce risk in terms ofreducing disruptions occurrence consequences, when the probabilities of their appearance remain at the same level.
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Gkrizis Vasileios, Leventakis George, Nikitakos Nikitas, Sfetsos Athanasios
Development of a risk assessment methodological framework for seaborders
Sea borders are identified as a major entry point in EU. In order to be adequately prepared to manage illegal immigrant’s inflow and mitigate the significant socioeconomic impact. The present paper introduces a comprehensive risk analysis methodological framework for the analysis of the present situation, risk prioritization and mitigation analysis. The proposed approach will be applied to a specific site in a N. Aegean Island, Greece as the country is the access point of over 80% of all immigration flow to the EU. [full text]
Grabski Franciszek
Decision problem for infinite duration semi-Markov
In the paper there are presented basic concepts and some results of the theory of semi-Markov decision
processes. The optimization problem for the infinite duration SM process is connsider in the paper. The
Howard algoritm which enables to find the optimal stationary strategy is also discussed here. The algorithm is applied in a decision problem concerning the two components renewable series system is. It is also shown that this algorithm is equivalent to the some linear programing problem. [full text]
Grigoriev Leonid, Kucheryavy Vladimir, Rusev Vladimir, Sedyh Ilya
Formation of estimates of reliability indicators for active elements in
gas transport systems on the basis of refusals statistics
The problem of equipment functioning reliability in gas transport systems is extremely urgent. This article deals with the algorithm of estimation and prediction of reliability factors of gas-compressor units and automatic systems, which uses statistical information about elements failures as input data. This algorithm is based on methods of mathematical statistics and regression analysis and provides the opportunity to obtain predictive estimate of failure rate, time between failures and availability function. In addition, the article describes the outcome of algorithm action, disagreement between industrial data about systems functioning and technical specification of these systems. [full text]
Gucma Lucjan, Marcjan Krzysztof, Przywarty Marcin
The analysis of the risk of an accident between a passenger ship and a tanker carrying hazardous substances in the Western Baltic
The paper presents an analysis of the accident between a passenger ship moving on the route Swinoujscie Ystad with tanker carrying hazardous substances category X. In order to assess the safety of navigation in the study area the authors have developed a probabilistic domain, which aims to estimate the number of incidents of navigation on the basis of real data from AIS and to find potentially dangerous areas, where there is the highest number of incidents. Then the vessel traffic model was built and the model of navigational safety assessment to evaluate the probability of Ro-Pax Ferry-Chemical tanker collision. Finally the consequences assessment of collision between Ro-Pax and chemical tanker carrying ammonia was performed, taking into consideration ammonia release. [full text]
Guze Sambor
The graph theory approach to analyze critical infrastructures of transportation systems
The main aim of the paper is to use algorithms and parameters of graph theory as tool to analyze the
transpiration systems. To realize this goal the well-known information about graph theory algorithms and
parameters will be introduced and described. The possible application of graph theory algorithms and
parameters to analyze the critical infrastructures of exemplary transportation system will be shown.
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Kołowrocki Krzysztof
Reliability of large and complex systems – state of art
The author’s latest monograph “Reliability of large and complex systems” published by Elsevier in 2014 is
presented. The paper is composed of an introduction, the monograph contents, conclusions and the references
the monograph contents is based on. [full text]

Kołowrocki Krzysztof, Soszyńska-Budny Joanna, Torbicki Mateusz
Reliability of large port grain transportation system
The combination of the results on the reliability of complex multi-state systems related to their operation
processes and the results concerning the limit reliability functions of the multistate systems is proposed, to obtain the results on the asymptotic approach to the evaluation of the large complex multi-state systems reliability at the variable operation conditions. The asymptotic approach to the large complex system reliability evaluation and the large complex system limit reliability function are defined. Limit reliability functions of selected large complex systems composed of components having Weibull reliability functions are fixed. The way of using this results is illustrated by their application to the evaluation of reliability characteristics of the large complex port grain transportation subsystem composed of three large multistate non-homogeneous series systems and changing its reliability structure and its components reliability parameters at variable operation conditions. [full text]

Kosmowski Kazimierz T.
Defence in depth conception in nuclear power plants and requirements for instrumentation and control systems
The aim of this article is to identify and discuss some issues of the safety systems’ design for nuclear power plants equipped with the light water reactors using a defence in depth (D-in-D) conception. Because the functional safety solutions play nowadays an important role for the risk control, the basic requirements for the instrumentation and control systems are specified with regard to relevant international standards. For the design purposes the safety functions are categorized into three categories. The I&C systems implementing these functions are assigned to one of three classes that conform to defined design, manufacturing and qualification requirements. These systems are designed to implement functions of relevant categories. Additional design requirements are discussed, including hardware and software aspects, to achieve and maintain the required reliability commensurate with the importance of the safety functions to be performed to reduce risk. [full text]
Lewandowski Krzysztof
Safety of delivery process in city centre, case study
The article presents the safety conditions of delivery to trade in the centre of city in Poland. The results are based on surveys the real 900 stores. This article analyses of reports the institution of the General Inspectorate of Road Transport. Indicated in the dependence of safe delivery of compliance with legal rules. Cause to write this article is situation on polish roads with delivery vehicles. [full text]

Nowakowski Tomasz, Młyńczak Marek, Werbińska-Wojciechowska Sylwia, Dziaduch Izabela, Tubis Agnieszka
Life Cycle Costs of passenger transportation system. Case study of Wroclaw city agglomeration
In the article authors are interested in the issues of LCC analysis implementation in the area of passenger transportation systems performance. In the first step of research analysis, there is provided a briefly literature overview of the analysed research area. Thus, the applicability of LCC analysis is investigated on the existing passenger transportation system located in Lower Silesia, Poland. [full text]

Smolarek Leszek, Wachnicka Joanna
Fuzzy regression approach to road safety analysis at regional level
Road safety modelling on regional level of NUTS 2 in the EU is the complex issue ant authors of this article indicate this in previous publications. During multivariate models development they discovered that it is difficult to make regression model well described all regions, even if they are from one country. In the first step Poisson model of road fatality rate as fatalities per 100 thou of citizens was prepared. In this article was presented the fuzzy regression approach to estimate lover and upper bounds of the modeled value. [full text]

Soszyńska-Budny Joanna
Complex technical systems safety prediction
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Woch Marta, Corbetta Matteo, Giglio Marco, Sbarufatti Claudio, Kamiński Grzegorz
Metropolis-Hastings method for Wohler curve parameter identification
In this work, the Metropolis-Hastings sampling technique has been used for the parameter identification of Wohler curve of aluminium alloy 2024-T4. The Metropolis-Hasting algorithm is one of the most widespread Markov chain Monte Carlo methods for posterior distribution estimation, and it is presented with an adaptive formulation to estimate the probability density functions of Wohler parameters. Results are presented in terms of distribution shape and parameter correlations. The information about parameter distributions of Wohler equation is useful to prepare risk analyses based on statistical safe life approach. [full text]