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Driven by applications using herringbone grooved bearings lubricated with a gas operating under conditions where the perfect gas assumption is not valid, the real gas effect has been introduced into the existing narrow groove theory. The enhanced model has been linked to a rotordynamic code and to a multi-objective optimizer resulting in optimum bearing geometries that differ from the ones under the perfect gas assumption. It is suggested that rotors on bearings that have been optimized under the perfect gas assumption may get unstable if they are submitted to a lubricant that operates close to the saturation line.

This paper focuses on applications in the area of WAMS (wide area measurement systems) and WACS (wide area control systems) development. A main issue is the report of an international cooperation oriented to test new algorithms and methods in this field. A feature of the cooperation has been the planning and carrying out of the common full-scale experiment in power systems aimed to investigate the feasibility in the implementation of new technologies of monitoring and control. The cooperation experience of the full-scale experiment at the Russian Far East Interconnected Power System is described in the paper.

In order to link electrochemical performance degradation of the cathode in a large solid oxide fuel cell (SOFC) to the presence of pollutant species, a spatially-resolved study of contaminants was performed. Distribution maps of pollutants over the cell allowed to identify their sources. Besides chromium and silicon, sulfur was found as a major pollutant species. Its preferential reaction with strontium doped lanthanum cobaltite (LSC), forming strontium sulfate SrSO4, compared to strontium doped lanthanum manganite (LSM) is revealed here. When sulfur poisoning arises in combination with chromium, a sulfur-containing strontium chromate compound is formed.

The global energy demand is growing substantially. Clean and secure energy supply is a must for our civilization's sustainable development. Solar and wind energy is growing fast and can contribute significantly to meet the goals set by many countries to reduce greenhouse gas emissions. A deep and wide investigation of the environmental impact of solar and wind energy is important before any solar or wind plants' construction is made. In this study, the literature is reviewed to summarize the environmental impact of solar and wind energy systems in terms of the following factors; land use, water consumption, impact on biodiversity, visual and noise effects, health issues, and impact on micro climate. Although the benefits of solar and wind energy are obvious and great, negative perception of these technologies can inhibit their wide penetration in some regions. This review paper includes a critical and an inclusive analysis of solar and wind energy’s environmental impact and may serve as an important tool to conduct a proper environmental impact assessment. This critical analysis may serve also as a tool for developers, policy, and decision-when planning future solar and wind farms.

Conventional historical data based material and energy balance analyses are static and isolated computations. Such methods cannot embody the cross-coupling effect of energy flow, material flow and information flow in the process industry; furthermore, they cannot easily realize the effective evaluation and comparison of different energy transfer processes by alternating the model module. In this paper, a novel method for material balance and energy conservation analysis of process industry energy transfer system is developed based on model property. Firstly, a reconfigurable energy transfer process model, which is independent of energy types and energy-consuming equipment, is presented from the viewpoint of the cross-coupling effect of energy flow, material flow and information flow. Thereafter the material balance determination is proposed based on both a dynamic incidence matrix and dynamic balance quantity. Moreover, the model-weighted conservation determination theorem is proved, and the energy efficiency analysis method is also discussed. Results confirmed the efficacy of the proposed methods, confirming its potential for use by process industry in energy efficiency analyses.

The science of statistics contributes to the development and application of tools for the design, analysis, and interpretation of empirical medical studies [...]