In order to understand the details of the diesel engine combustion process, the combustion of a turbocharged and intercooled diesel engine was simulated with the commercialized computational fluid dynamics software STARCD. To define the initial conditions of the simulation, such as pressures, temperatures,etc., the diesel engine was tested on a dynamometer testbed under different fuel supply advance angles to get its smoke and NOx emission behaviors. The combustion processes were simulated under the testing conditions. The simulation results show that a fuel spray tip is formed during the fuel injection process, and the spray tail breaks off from the main spray towards the end of injection. The unburned fuel impinges on the combustion chamber wall, then a part of which moves up into the clearance space between the piston top and the cylinder head bottom, and the majority of the impinged fuel moves down along the ωtype chamber wall to form a tumble flow. The ignition always occurs in the outer region of the fuel spray, the combustion goes on there, so the temperatures there are high.

Based on Kalman filtering theory, aiming at the multisensor system during the transport information collection two models of traffic information fusion using the data from several transport detectors were proposed. Based on the concept the fusion models for three detection equipments were built and were tested by the detected data. The results show that these two models are reasonable and effective for improving the detection precision.

A popular segmentbased proxy caching scheme for streaming media was proposed. This scheme was based on the existing technologies, such as the prefix and segmentbased caching strategies. In this scheme the fact that most accesses are targeted toward a few popular objects or partials of an object is taken into account. The popular segments are cached on the client and the size can be dynamically changed according to the client access behaviors in real time. The admission and eviction of segments are carried out by an accurate utility function, which is better than the adaptive and lazy segment caching strategies in improving the client perceived startup latency. Simulation results indicate that, comparing with existing strategies, the proposed scheme performs better in byte hit ratio, client startup delay, network traffic and cache space.

In order to eliminate Doppler effects in moving sound source identification by acoustic holography, a wavelet transform based method was presented. Theoretical model of the moving sound source identification was provided. Doppler effects were analyzed and its solution was given. Simulation results show that the presented method can accurately identify the moving sound source and has more in line with actual sound source position compared with the traditional methods. In addition, it can overcome shortcomings of the original methods that the Doppler effects can only be eliminated when true frequency of the sound source is known apriori. And the proposed method can improve the identification accuracy and calculation efficiency of the moving sound source identification.