Research On Key Techniques Of Radio Resource Allocation In Relay-enhanced Cellular Networks

Nowadays, noise pollution is an important part of urban pollution, which leads to a serious impact on the daily life of humankind. Especially with the developing of automobile industry and urban transportation, the urban car ownership increases year by year and the noise pollution led by the automobile becomes more and more serious. As an important source of the urban noise, traffic noise shows an effective way to reduce the urban noise – reducing the noise that comes from the automobile.During the design process, the noise performance is now an important index of the designed automobile along with its dynamic performance and economic performance etc. The drive axle is an important part of the driving system of the automobile, in which the final drive is one of the main noise source of the automobile noise.As an important index, noise should be taken into account during the designation of the drive axle. On the condition that the dynamic performance and transmission performance meet the design requirements of the drive axle, simulation and improve design on the transmission performance and noise index of the designed gear is of great significance on the reduce of the automobile noise.To improve the stability and reduce the noise of the automobile during the runtime, attempts on the designation and analysis are finished for the hypoid gear pair of the driving axle. The main contents are:1. The structures, function and its characteristic of the driving axle are introduced for the automobile. The classification and characteristics of the gear in axle is shown. Then the function of the tooth surface parameters and analysis methods of the results are reviewed for the hypoid gear which is chosen for the driving axle.2. The common software and its characteristics for hypoid gear designation and analysis is introduced. Then detail description on the function and method of application for the software named Gleason Spiral Bevele/Hypiod Gear Design, which is chosen to design the hypoid gear, is presented.3. According to the design requirements of the hypoid pear of drive axle for R101-type mini-car, hypoid pair is designed with Gleason software. Then works on the analysis of the transmission performance for the gear train with ROMAX is done to provide suggest for the optimization of the hypoid gear pair.