Context: Verification and validation (V&V) activities make up 20 to 50 percent of the total development costs of a software system in practice. Test automation is proposed to lower these V&V costs but available research only provides limited empirical data from industrial practice about the maintenance costs of automated tests and what factors affect these costs. In particular, these costs and ...

Nowadays, shovels play an important role in production of open pit mines and their failures result in significant production loss and considerable increase in maintenance costs. Therefore, reliability and risk analysis can help to improve production, productivity and reduce production costs. In this study, reliability of electric cable shovel of Chadormalu iron ore mine in Iran was investigated...

Abstract This paper addresses the questions: How to calculate cost of a start/stop cycle? running one hour outside normal operating range, e.g., on part load? The presents model for calculation individual hydropower units comprising both direct costs incurring at each cycle, and indirect because reduced rehabilitation intervals main components. fundamental assumption is that frequent start-ups ...

during the human history, there was a great struggle against illness and pain, and physicians have always been vanguard in this fight, but some physicians, in addition to treating patients, have been doing their actual duty, namely the maintenance of human health. in the ancient medical history resources, issues of health protection have been shown to be one of the most significant subjects of ...

Achieving optimal production cycle time for improving manufacturing processes is one of the common problems in production planning. During recent years, different approaches have been developed for solving this problem, but most of them assume that mean quality characteristic is constant over production run length and sets it on customer’s target value. However, the process mean may drift from ...

Exergy analysis is based on combined first and second laws of thermodynamics and is a useful tool to analyze the energy systems in a better and more realistic way than an energy analysis, based on the first law of thermodynamics. Combination of exergy from thermodynamics with conventional concepts from engineering economy which is referred to as thermo-economy (exergo-economy) is a valuable too...

An important part of the lifecycle costs for pump stations are the support costs associated with energy and preventive maintenance of the pumps. Both cost terms are interrelated because a trade-off exists between maintaining pumps frequently (with increased pump efficiency, reduced energy costs and increasing maintenance costs, and pump unavailability) and extending the intervals between the ov...