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Thispaper presents an open standard based, service-oriented infrastructure for provisioning, managing and developing telematics services. Within this end-to-end infrastructure, a novel context aware service architecture has been proposed to acquire, deliver, process, derive and deploy context for enhancing the safety and convenience of the vehicles.

Research has proven that the performance of a horizontal axis wind turbine (HAWTs) can be increased significantly by the application of a diffuser. It serves as a power augmented feature to draw higher wind flow toward the HAWT. However, research on integrating a diffuser onto vertical axis wind turbines (VAWTs) is scant, where most of the available power augmentation devices used for VAWTs are the convergent duct, deflector plate, shroud, and guide vanes which are placed in a proper configuration at the upwind. In this paper, laboratory tests and computational simulations have been carried out to study the impacts of a downwind diffuser on the performance of a VAWT. The diffuser is designed with the absence of a concentrator or flange and is placed downwind of the VAWT. Parametric computational fluid dynamics (CFD) studies were carried out for the downwind diffuser length and semi-opening angle. A five-bladed H-rotor was selected as the testing wind turbine, whereas the diffuser used was made up of flat plates. Both simulations and experiment results are consistent. From the experiments, it was found that a downwind diffuser increases the VAWT performance remarkably. The diffuseraugmented VAWT produced an increment in the maximum coefficient of power of 31.42% at the TSR 0.65 to 0.75. Moreover, the diffuser induced a better self-start ability on the VAWT. The simulation showed that the flow field at the diffuser promotes a flow expansion which created a lower-pressure region at downstream that accelerates the wind toward the VAWT, hence increasing the turbine performance significantly.

Optimization degree of risk population allocation on evacuation route is one of the key points impacting emergency evacuation efficiency in dam-break event.The evacuatees optimization allocation mechanism considering route flow and route length was studied; optimization degree evaluation methods based on submerged number were constructed; corresponding formula for calculating submerged number was deduced; optimization degree classification and its standards were put forward; its availability was proved through case simulation.

A variety of research approaches have emerged after the concept of Gibson's affordance was introduced in design field, for example, the relationship approach in design research and the approach of cognitive science research after Norman. The significance of affordance-based design for methodology forming ecological design theory is discussed in this article. The significances are to surmount defects resulting from function-oriented design theory and to pave the ecological approach to design theory with directness and embodiment combining perception with activities.