The safety case and the lessons learned for the reliability and maintainability case

This paper examine the safety case and the lessons learned for the reliability and maintainability case

Expert Elicitation for Reliable System Design

This paper reviews the role of expert judgement to support reliability assessments within the systems engineering design process. Generic design processes are described to give the context and a discussion is given about the nature of the reliability assessments required in the different systems engineering phases. It is argued that, as far as meeting reliability requirements is concerned, the whole design process is more akin to a statistical control process than to a straightforward statistical problem of assessing an unknown distribution. This leads to features of the expert judgement problem in the design context which are substantially different from those seen, for example, in risk assessment. In particular, the role of experts in problem structuring and in developing failure mitigation options is much more prominent, and there is a need to take into account the reliability potential for future mitigation measures downstream in the system life cycle. An overview is given of the stakeholders typically involved in large scale systems engineering design projects, and this is used to argue the need for methods that expose potential judgemental biases in order to generate analyses that can be said to provide rational consensus about uncertainties. Finally, a number of key points are developed with the aim of moving toward a framework that provides a holistic method for tracking reliability assessment through the design process.Comment: This paper commented in: [arXiv:0708.0285], [arXiv:0708.0287], [arXiv:0708.0288]. Rejoinder in [arXiv:0708.0293]. Published at http://dx.doi.org/10.1214/088342306000000510 in the Statistical Science (http://www.imstat.org/sts/) by the Institute of Mathematical Statistics (http://www.imstat.org

Attributes of Online Business in Romania during Economic Crisis

Any business seeks maximum profitability. Especially when the global economic crisis grows, a company must have both maximum profitability by reducing costs, and by finding new markets and new consumers. Due to economic conditions, companies have turned to online business, where operating costs, and marketing costs are much lower. Almost every company in the world, who noticed the trend, they promote, in one way or another, the own business on the Internet.online business, economic crisis, business model, social media

Review and Comparison of Intelligent Optimization Modelling Techniques for Energy Forecasting and Condition-Based Maintenance in PV Plants

Within the field of soft computing, intelligent optimization modelling techniques include various major techniques in artificial intelligence. These techniques pretend to generate new business knowledge transforming sets of "raw data" into business value. One of the principal applications of these techniques is related to the design of predictive analytics for the improvement of advanced CBM (condition-based maintenance) strategies and energy production forecasting. These advanced techniques can be used to transform control system data, operational data and maintenance event data to failure diagnostic and prognostic knowledge and, ultimately, to derive expected energy generation. One of the systems where these techniques can be applied with massive potential impact are the legacy monitoring systems existing in solar PV energy generation plants. These systems produce a great amount of data over time, while at the same time they demand an important e ort in order to increase their performance through the use of more accurate predictive analytics to reduce production losses having a direct impact on ROI. How to choose the most suitable techniques to apply is one of the problems to address. This paper presents a review and a comparative analysis of six intelligent optimization modelling techniques, which have been applied on a PV plant case study, using the energy production forecast as the decision variable. The methodology proposed not only pretends to elicit the most accurate solution but also validates the results, in comparison with the di erent outputs for the di erent techniques

Reputations, Relationships and the Enforcement of Incomplete Contracts

This paper discusses the literature on the enforcement of incomplete contracts. It compares legal enforcement to enforcement via relationships and reputations. A number of mechanisms, such as the repeat purchase mechanism (Klein and Leffler (1981)) and efficiency wages (Shapiro and Stiglitz (1984)), have been offered as solutions to the problem of enforcing an incomplete contract. It is shown that the efficiency of these solutions is very sensitive to the characteristics of the good or service exchanged. In general, neither the repeat purchase mechanism nor efficiency wages is the most efficient in the set of possible relational contracts. In many situations, total output may be increased through the use of performance pay and through increasing the quality of law.contract, law and economics, reputation, repeated games, incomplete contracts, transactions costs, institutional economics, contract enforcement