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In this paper the crashworthiness of a thin-walled column is selected as the optimization goal and its section gauge size parameters are defined as variables. We use Optimal latin hypercube design method and ASA optimization method respectively to define sampling design points and find optimal design in Kriging metamodel, constructed using function values in FEM results at sampling design points. A design space updating method is introduced in this paper to reduce computational consumption and improve accuracy by several rounds of metamodeling and optimization, practice shows that object parameter SEA in each round converge to a final one, constrained by the demand of no weight added. High accuracy and rapid convergence of this method will be verified by comparison between results by this method and FEM.

This article describes a method, based on drum test and performance of drive axle test, to find the distribution of resistance itself and its relationship with speed in whole driveline and drive axle by processing data from the results of test. A related analysis equation can be found by analyzing the power consumption with different torque inputs.

To meet the operating requirements and give full play to the efficiency of thread fasteners, a method to calculate tighten torque was developed on the basis of pre-tightening force-torque characteristic curve. Compared the traditional method depended on empirical values, the method proposed in the paper can not only consider the theoretical analysis, but also combine experiment results. Through calculating the tighten torque of a car engines bearing bolts by pre-tightening force-torque characteristic curve method, and comparing the results and the practical torque value, it demonstrates that the pre-tightening force-torque characteristic curve method can develop more efficiency of the bolt.

To solve the problem of lacking tools for efficiency testing in the process of automotive driveline optimization, a test bench was developed on the basis of adequate study on the properties of the structure of automobile driveline. Using the test technology to carry out efficiency research of automotive driveline, can not only verify the theoretical analysis, but also find an effective way to improve the efficiency of automotive driveline through the processing of testing data. In the past, most of the research for driveline efficiency is limited to the study of automotive transmission, and it is seldom acceptable to take the entire driveline as the research object to study. Adopting modular structure design, this test bench can not only be used to test the efficiency of entire automobile driveline, but also be used to test the efficiency of single components. Testing results shows that the precision of the test bench has achieved the anticipated goal, and the test bench has the advantages of convenient installation and high automation degree, etc.

This paper has made a statistic survey on the failure rate of the appliance of high-power IGBT on the Harmonious locomotive. According to the analysis ,environmental temperature and humidity have a crucial influence on failure rate, thus a set of temperature and humidity monitoring system has been designed to investigate the environment temperature and humidity of high failure rate Four-quadrant IGBT modules, analyzing factors such as temperature and humidity and the working conditions accordingly, exploring the relationship of rising temperature of IGBT ,locomotive speed ,pressure of the air cylinder, setting a foundation for later analysis on the mechanism of troubles.

Based on formulating the minicar transmission efficiency test standard,the test was designed by using dimensional analysis theory. Selected the power loss of transmission system as evaluation index, the effects of parameters such as oil temperature,oil depth of stir oil gear, line speed of stir oil gear, transmission system ratio, input speed and input torque were experimented. It has the advantages of less test times and more design freedom. The test design provides theory basis for the empirical formula which indicates the relationship between power loss and test parameters.

The control system of automatic clutch is based on the manual gearbox instead of the clutch pedal. It realizes automated clutch and manual shifting. The essence of automatic clutch is how to control the motor drive unit to achieve the implementation of the automatic clutch separation and bonding, and thus automatic speed technology of motor is the key. In this paper, combining the characteristics of micro-car, a double-loop automatic motor speed control system is designed. The design is proved reasonable and feasible through simulation based on MATLAB.

In order to seek methods of reducing the coolant resistance of radiators in mini-vehicle, the resistance distribution in minicar radiators was obtained by carrying out numerical simulation to coolant flow field of the radiators. The analysis indicated that the coolant resistance mainly composed of two parts: the resistance along radiating pipes, the inlet and outlet resistance of the water tank. Reducing the surface roughness of coolant pipes could lower the resistance along pipes. Slowing down the changes of the inlet and outlet section could reduce the local resistance.

The non-ball mill is a new-type grinding equipment that is developed on the foundation of the successful technology of vertical shaft breaker, vertical mill, roller etc., its principle is to make the movement route of attacking the supply in the machine to be redesigned , the grain reaches to break once only through constantly accumulating energy in the grain, the crushing ratio is big, especially this machine adopt the advanced technology, the vulnerable part is made of metal and nonmetal, which make the life-span lengthens ten times than the alloy hammer’s, which is invention in the world . The average size of this machine is smaller than 1 mm, it is not only suitable for soft quality supplies but also further more superior for hard quality supplies performance.

Short pulse lasers, including picosecond laser and femtosecond laser are involved to investigate the ablation characteristics of processing carbon fiber reinforced plastics (CFRPs). The ablation threshold of the femtosecond laser, 0.453 J/cm2, is twice higher than that of the picosecond laser 0.867 J/cm2, since the former generates an intense and shorter pulse and the atoms excitation and multi-photon absorption may occur as short as 10 ps or less. The ablation test also describes the processing qualities, where the femtosecond laser has processing abilities without visible thermal defects or charring over the picosecond laser.

A raw mill’s production line is to grind the raw material mixed with limestone, clay and basalt of certain proportion; it decides the quality of the cement clinker. The production efficiency and quality can be promoted by precisely controlling the proportion of the three raw materials and feeding automatically. The system’s controller is S7-400, and the measurement is done by the rotor scale produced by SHENCK. The variable speed device (VSD) of the feeder was controlled by the flow through the PID controller to realize the precise proportion. Moreover, the proportion can be set and the feeding quantity, the producing process can be monitored by the position machine (Win CC), to achieve production automation.

According to the national test standards for constant speed friction tester :GB/5763-98, the sample test is designed which suits for the study of the micro-automobile clutch friction material’s properties, and the experiment data has been analyzed, and also using X-ray diffraction and Scanning electron microscopy(SEM) to analyze the friction coefficient of friction material, changes in wear quality and the formation of friction work surface layer, the final conclusion has been made that the micro-automobile clutch sliding wear consist of mild wear and severe wear; The friction surface of mild wear is relatively rough, while the friction surface of severe wear is relatively smooth or with obvious noise; mild wear mostly appears as oxidation wear and abrasive wear and normally with the adhesive wear together, while severe wear is mostly induced by severe plastic deformation(serious delaminating wear) , and mostly appears as adhesive wear and abrasive wear.

To explore the substantial cause of the early abnormal wear of micro-vehicle clutch’s friction material, the sample test aimed at studying the tribological properties of micro-vehicle clutch’s friction material is designed, according to GB/5763-98 national test standards. The broken line graph of samples’ friction coefficient on and wear rates in different working conditions are obtained. There are two types of working conditions. One is the same line speed and different working loads of samples, and the other is the same working load and different line speeds. Combined Scanning Electron Microscopy (SEM)’s observation with tribological principle, the sample test result is analyzed, thus obtaining the changing rules of the materials’ friction coefficient and wear rates at different temperatures, working loads and line speeds.

The wide application of information technology has greatly improve the work efficiency but also caused a large and complex data accumulation. How to get the valuable information from vast amounts of data are the key issues in data processing. This paper studied the application of data mining technology in tobacco commercial enterprise from three aspects: market demand forecasting, customer relationship management and historical data processing. Analysis of how to use data mining technology to make full use of large amounts of data to provide a basis for tobacco commercial enterprise’s decision-making.