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Service Oriented Computing SOC is a popular software paradigm that is widely employed in IT industry. SOC uses "services" as the unit of functionality of a software application. The massive wave of SOC applications involve considerable energy consumption of servers, which should not be ignored in large-scale computing environment. When a service requirement can be answered by several web services, the energy consumption for each service to response the service request may be different. When this happens, Web Service Selection (WSS) is often required to choose appropriate services to maximize global energy efficiency of SOC applications. Accordingly, this paper proposes a Virtual Power Meter Supported Power Consumption Prediction method for WSS (VPMSPCP). VPMSPCP facilitates choosing appropriate services to minimize wasteful electrical energy from the overall environment of SOC applications. According to our empirical proof, there is a correlation between the power consumption of a service and the status of the server where this service resides. We take advantage of this discovery to develop VPMSPCP by combining an aggregate multiple regression model with a well-known web service power modeling method. There are mainly two steps to establish VPMSPCP. First, we develop a virtual power meter (VPM) for each server. We use a VPM to estimate the average power of a server under a certain status. Second, we apply the VPM to VPMSPCP to estimate power consumption of a web service according to the current status of the servers where the copies of this service reside. Experiments show that VPMSPCP performs well in improving energy saving in WSS.

Synchro-Self-Shifting (SSS) clutch is used widely in the ship propulsion system, power plants and other plants. It is one of the most important parts during the system and needed to be simulated in the simulation research of power plant system. However, the mathematical model of the SSS clutch has almost never been presented in the existing published research reports. It has been shown that the transmission characteristics of the clutch have a direct impact on the performance of the power plants in the actual experience. The paper presents a mathematical model of the SSS clutch with the couple sliding components, which is established on the basis of the motion process analysis and the comparison with the general structure. The established model’s simulation research work has been completed on the platform of MATLAB / Simulink, with emphasis on the response of the movement characteristics and the damping cavity structure. The simulation results are in line with the kinematics law of the SSS clutch, which are well shown that the established SSS clutch is valid and can be used in further research and practical application.