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This study aims to explore the influence of a vehicle front-end shape on pedestrian and cyclist injuries. The injuries of head, upper leg and lower leg based on 50th human model are considered as design response. A multi-objective optimization approach is developed to design and optimize the front shape for minimizing injury risks of pedestrian and cyclist in this study. The numerical models of pedestrian-vehicle and cyclist-vehicle impact is constructed and validated first. Then, the optimal Latin hypercube sampling (OLHS) method is adopted for design of experiment (DOE) and the surrogate model is constructed through radial basis function (RBF). The optimal problems involving a number of objectives are solved by the multi-objective particle swarm optimization (MOPSO) algorithm in this study.

The unevenness between cylinder's operations for multi-cylinder engine Is one of the most important factors affecting an the engine performance. The authors presented a new approach to diagnose it, that is, deriving each cylinder's compression pressure, maximum combustion pressure and work from the transient crankshaft speed. The diagnostic principle and calculating method of pressures and work were described in detail, the experimental equipment and results were illustrated. The derived work, compression engine and combustion pressure were compared to their measured values. Figures and tables were given. The first phase of study indicated that the diagnostic method above is acceptable and simple, after enhanced it's accuracy futher, it will find good use.

In this paper authors propose a new method for estimation of cylinder compression. Under motoring condition, when the transient rotational speed fluctuation of flywheel within a working cycle has been measured, the Max. compressive pressure of each cylinder were calculated based on the principle of inertia acceleration. The testing results of 4 and 6 cylinder engines show that, the measured errors were within ±3%, so it is a proper tool for fast estimation the compression of engine mounted on vehicles especially.

The heat release rate patterns of fuel combustion determines the changing of pressure and temperature of gases within cylinder, and furthermore made an important effect of the fuel economy, power - output, noise level and exhaust emission. In this paper, the authors discuss the fuel economy, power - output and combustion noise of R4102Q D.I. diesel engine. In optimum simulation concerning fuel economy and power-output, the indicative heat efficiency and mean indicative pressure were almost always taken as objective function. In consideration of the effect of gas pressure upon the friction losses of diesel engine, the effetive heat efficiency and mean effective pressure were taken as objective function in this paper. By comparison with testing data, when the instantaneous friction was taken into consideration, the prediction accuracy of simulations was improved.