<p>For technical systems in the electricity and paper and pulpindustries, asset management is emerging as a new approachaddressing how to exploit physical assets with long operativelives in the most profitably way. An important problem forasset management staff is knowing when to carry out areplacement or renewal. This is a difficult question whichrequires taking into consideration parameters of totallydifferent natures–e.g. reliability data, operatingcosts, condition information from technical systems, theenvironment and rules and regulation. An incorrect estimate ofa residual lifetime can result in a premature renewal withaccompanying high capital costs. If, however, renewal isdelayed, a breakdown may occur which can cause major damage totechnical equipment and a loss of income due to outages.</p><p>This work presents a formal model that calculates expectedcosts of different long-term strategies when managing technicalsystems. It is shown that with relatively few inputs, which inmany cases are easy to collect or estimate, a good picture canbe developed that shows the amount of resources a company willneed in the future in terms of renewals of their technicalsystems. The foundation for this work is a case study and aliterature review; the objective was to study what methods andmodels are in use today when estimating residual lifetime oftechnical systems. Also, aspects that influence long-term assetmanagement were investigated. Lessons learned from the casestudy and literature review were then used to develop a dynamicmodel, the Dynamic Lifetime Analysis model (DLA model).</p><p>This model is based on a probabilistic and dynamic riskanalysis of a technical system, linking different aspects ofrisk management strategies to specific characteristics of thephysical system. Furthermore it is shown how this model,coupled with specific value judgments, can be used to designoptimal long-term strategies. When taking more than onetechnical system under consideration the model shows that it isnot always the most effective, from a system viewpoint, torenew it too close to a possible breakdown. If there is aperiod predicted to incur high investment, it can, at times, bebetter to do an early renewal thereby maintaining resources ata constant level. The thesis also describes how to work withlong-term strategic decisions in a structural manner in orderfor the actors on a deregulated market to stay competitive.</p><p><b>Key Words:</b>Residual lifetime estimation, Assetmanagement, Maintenance, Technical systems in power and pulp-and paper industries, Long terms renewal strategies.</p>

For technical systems in the electricity and paper and pulpindustries, asset management is emerging as a new approachaddressing how to exploit physical assets with long operativelives in the most profitably way. An important problem forasset management staff is knowing when to carry out areplacement or renewal. This is a difficult question whichrequires taking into consideration parameters of totallydifferent natures–e.g. reliability data, operatingcosts, condition information from technical systems, theenvironment and rules and regulation. An incorrect estimate ofa residual lifetime can result in a premature renewal withaccompanying high capital costs. If, however, renewal isdelayed, a breakdown may occur which can cause major damage totechnical equipment and a loss of income due to outages. This work presents a formal model that calculates expectedcosts of different long-term strategies when managing technicalsystems. It is shown that with relatively few inputs, which inmany cases are easy to collect or estimate, a good picture canbe developed that shows the amount of resources a company willneed in the future in terms of renewals of their technicalsystems. The foundation for this work is a case study and aliterature review; the objective was to study what methods andmodels are in use today when estimating residual lifetime oftechnical systems. Also, aspects that influence long-term assetmanagement were investigated. Lessons learned from the casestudy and literature review were then used to develop a dynamicmodel, the Dynamic Lifetime Analysis model (DLA model). This model is based on a probabilistic and dynamic riskanalysis of a technical system, linking different aspects ofrisk management strategies to specific characteristics of thephysical system. Furthermore it is shown how this model,coupled with specific value judgments, can be used to designoptimal long-term strategies. When taking more than onetechnical system under consideration the model shows that it isnot always the most effective, from a system viewpoint, torenew it too close to a possible breakdown. If there is aperiod predicted to incur high investment, it can, at times, bebetter to do an early renewal thereby maintaining resources ata constant level. The thesis also describes how to work withlong-term strategic decisions in a structural manner in orderfor the actors on a deregulated market to stay competitive. <b>Key Words:</b>Residual lifetime estimation, Assetmanagement, Maintenance, Technical systems in power and pulp-and paper industries, Long terms renewal strategies. / NR 20140805

Prior researches in P2P file sharing mostly focus on several topics such as the overlay topology, the content searching, the peer discovery, the sharing fairness, incentive mechanisms, except scheduling algorithms for peer-to-peer collaborative file distribution. The scheduling algorithm specifies how file pieces are distributed among peers. When a peer that has the rarest piece leaves, the other peers probably download the incomplete file in the network. Our algorithm is involved in the lifetime of peers in the P2P networks. We first use the distribution of peer¡¦s lifetime and the demand of each peer to decide which peers send which pieces that are rarities, and then also consider the distribution of peer¡¦s lifetime and the demand of each peer to decide which peers receive these pieces. Our goals are to maximize number of peers which have downloaded an entire file before it leaves, to increase the availability of different file pieces, and to minimize the transmission time of the latest completion. Lastly, we show the comparison of the performances of RPF, MDNF, Lifetime-based RPF, and Lifetime-based MDNF algorithms.

The objectives of this work is residual lifetime of heaters in petrochemical industry. There is no comprehensive publication about this theme. This paper lists and describes the most of main phenomena that has to be taken into account in the process of determination of residual lifetime. This paper focuses on creep damage of a real heater based on deformation measurement. It describes some heater failures that could cause unplanned operation interruption however, appropriate intervention made possible safe heater operation until planned heater shutdown. No compact method is given how to determine heater residual lifetime, but a direction is given how a complex method of residual lifetime assessment of refinery heaters could be created.

<p>For complex technical systems in the electricity and pulp and paper industries, maintenance management addresses how to exploit physical assets in the most profitably way. This is a difficult task that requires taking into consideration parameters of totally different natures – e.g. reliability data, operating costs, condition of technical systems, the environment and rules and regulation.</p><p>An incorrect estimate of a residual lifetime can result in a premature renewal with accompanying high capital costs. If, however, renewal is delayed, a breakdown may occur which can cause major damage to technical equipment and a loss of income due to outages. Because of the complexity of many technical systems, it can be hard to select adequate data to use when making decisions about renewal strategies. To cope with this, one approach is to use less detailed models that are operated by skilled analysts.</p><p>This work demonstrates the advantage of such an approach by proposing two methods applied in a joint methodology that has its origins in RCM. The methodology consists of Dynamic Lifetime Model (DLA) and the Condition Based Index (CBI). The DLA method copes with the financial risk associated with the point in time for when a renewal is carried out and the CBI method uses critical parameters to estimate the condition of a technical system. The two methods together create a quantitative connection between reliability, maintenance and financial risk. A case study based validation of the methodology was carried out at SCA Ortvikens paper mill on a refiner system and Forsmark nuclear power plant. Lessons learned from the case study showed that the methodology could be used to identify which components could cause costly breakdown. By using the methodology a manager gets a decision support tool for estimating short-term and long-term consequences of decisions regarding maintenance management in order to maximize utility of the system concerned</p>

For complex technical systems in the electricity and pulp and paper industries, maintenance management addresses how to exploit physical assets in the most profitably way. This is a difficult task that requires taking into consideration parameters of totally different natures – e.g. reliability data, operating costs, condition of technical systems, the environment and rules and regulation. An incorrect estimate of a residual lifetime can result in a premature renewal with accompanying high capital costs. If, however, renewal is delayed, a breakdown may occur which can cause major damage to technical equipment and a loss of income due to outages. Because of the complexity of many technical systems, it can be hard to select adequate data to use when making decisions about renewal strategies. To cope with this, one approach is to use less detailed models that are operated by skilled analysts. This work demonstrates the advantage of such an approach by proposing two methods applied in a joint methodology that has its origins in RCM. The methodology consists of Dynamic Lifetime Model (DLA) and the Condition Based Index (CBI). The DLA method copes with the financial risk associated with the point in time for when a renewal is carried out and the CBI method uses critical parameters to estimate the condition of a technical system. The two methods together create a quantitative connection between reliability, maintenance and financial risk. A case study based validation of the methodology was carried out at SCA Ortvikens paper mill on a refiner system and Forsmark nuclear power plant. Lessons learned from the case study showed that the methodology could be used to identify which components could cause costly breakdown. By using the methodology a manager gets a decision support tool for estimating short-term and long-term consequences of decisions regarding maintenance management in order to maximize utility of the system concerned / QC 20111216

A distribuição bivariada de Marshall-Olkin é estendida, relaxando-se a hipótese de choques exponencialmente distribuídos e assumindo-se dependência entre os choques individuais. Abordagem semelhante é considerada para sua versão dual. Representação por meio de cópula, propriedades probabilísticas e de confiabilidade assim como resultados em valores extremos são então obtidos. A propriedade de falta de memória bivariada é estendida assumindo-se uma função de dependência sem memória. Uma nova classe de distribuições caracterizada por essa propriedade estendida é introduzida. Correspondentes interpretações geométricas, procedimentos de construção, representação estocástica, relação com cópula de sobrevivência e propriedades de confiabilidade são derivadas. / Bivariate Marshall-Olkin model, Dual model, Exponential representation, Dependence function, Bivariate aging, Copula, Survival copula, Stochastic order, Bivariate extreme value distribution, Pickands measure, Pickands dependence function, Failure rate, Bivariate hazard gradient, Bivariate lack-of-memory, Residual lifetime vector, Characterization.

A distribuição bivariada de Marshall-Olkin é estendida, relaxando-se a hipótese de choques exponencialmente distribuídos e assumindo-se dependência entre os choques individuais. Abordagem semelhante é considerada para sua versão dual. Representação por meio de cópula, propriedades probabilísticas e de confiabilidade assim como resultados em valores extremos são então obtidos. A propriedade de falta de memória bivariada é estendida assumindo-se uma função de dependência sem memória. Uma nova classe de distribuições caracterizada por essa propriedade estendida é introduzida. Correspondentes interpretações geométricas, procedimentos de construção, representação estocástica, relação com cópula de sobrevivência e propriedades de confiabilidade são derivadas. / Bivariate Marshall-Olkin model, Dual model, Exponential representation, Dependence function, Bivariate aging, Copula, Survival copula, Stochastic order, Bivariate extreme value distribution, Pickands measure, Pickands dependence function, Failure rate, Bivariate hazard gradient, Bivariate lack-of-memory, Residual lifetime vector, Characterization.