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The study object is Hybrid Electric Vehicle (HEV) with front-wheel drive (FWD) pattern and wire-controlled braking system. The relations between pavement adhesion coefficient and recovery efficiency of regenerative braking were discussed. Consequences were concluded through theoretical derivations basing on the two-wheel model. Simulations were built and simulated within a certain HEV on the platform in MATLAB/SIMULINK. The results indicate that the recovery efficiency would experience an upward trend if the pavement adhesion coefficient declines.

Hydrodynamic characteristic is an important reference to select vegetation material of ecological revetment engineering. In this paper, embankment will be divided into bottom-protection zone, key-protection zone, hydrophilic zone, landscape zone according to hydrodynamic characteristics of different water levels. Vegetations adapting to different protection area analyzed and discussed. With the example of ecological revetment in Naji reservoir in Guangxi, China, vegetation selection on different protection zone is demonstrated.

Wind power prediction is very important to maintain the power balance and economic operation of power system. The BP and RBF neural network were respectively used to predict one wind turbines’ output power, in 4 hours, on a wind farm in Shandong Province. The results show that the BP model, with 6-13-1 net structure and considering the meteorological factors, exhibits the best prediction accuracy (MAPE is 3.59%, NRMSE is 1.58%). The most important factor in the meteorological information for power prediction is temperature, followed by air pressure, relative humidity finally. BP model is slightly better than RBF model, but the latter is much better in the learning speed and stability. Dynamic-BP neural network, combined with the dynamical weight adjustment method, is better than BP neural network in solving the weight problem. These methods are feasible to the wind power prediction.

Node modeling of wind farm in power flow calculation is an issue which must be solved. This paper described mathematical model of asynchronous generator which be used widely, elaborated mathematical model and calculation process of several wind farm node models in power flow calculation, discussed calculation speed and accuracy of every model and pointed out that under the premise of high level calculation speed, how to add wake effect to power flow calculation process will be a significant direction for wind farm modeling studies.

Based on the nonlinear finite element method, the basic characters of widened road engineering are studied. It is found that the maximal lateral displacement of embankment achieved in the widened part, especially happened at the intersection between original part and widened part, which increased with the width of widened part increased. The maximal vertical settlement of embankment increased with width of widened part increased. The width of widened part has little influence on the failure surface and stability of embankment.

This article introduces the development of domestic and foreign small power multi-cylinder diesel engines which are below 37kW. It analyzes the structural characteristics of foreign products and clarifies the status of domestic small power multi-cylinder diesel engines as well as the causes which limit their development. It also points out that with the tightening of the emission regulations of non-road diesel engines, We need to develop high-performance small power multi-cylinder diesel engines which are compact, energy saving and environmental friendly to meet market demands at home and abroad. Based on the status quo of the domestic industry, it illustrates the development problems of small power multi-cylinder diesel engines that deserve our attention and the corresponding technical countermeasures, and provides recommendations on the development of the domestic industry.

This article proposes a new method for the extraction of five parameters of a solar cell using Lambert W-function with the current-voltage data. Here we select three points: the short circuit point, the open circuit point, and the maximum power point. On the basis of these we construct five equations to establish a nonlinear formula, in which the series resistance can directly be obtained. The other four parameters are calculated by series resistance. This method is confirmed by two different solar cell data in Matlab software.

A typical slope has been comparatively analyzed with 2D and 3D FEM, it is showed that the length of surface load at top surface of slope shorted, the stability factor of slope of 3D model increased, which is far more than that of 2D model. In a certain degree, the safety factor got by 3D model is bigger than that of 2D model, so the safety factor of slope is underestimated by 2D model analysis sometimes.

The state of art of tunnel earthquake damages and tunnel earthquake damage mechanism are briefly introduced in this paper. According to tunnel’s traffic function and damage descriptions based on the investigation, tunnel damages are divided into five grades: no damage, minor damage, moderate damage, major damage and collapse, and their corresponding damage index range and characteristic values are defined. The influence of tunnel materials in Kobe earthquake and Chi-Chi earthquake are collected in this paper, and the damage grades are determined based on the performance in the earthquake. After comparative analysis, the seismic intensity, overburden depth, rock classification, distance to faults and the tunnel length are chosen as the seismic damage influence factors. A formula for tunnel seismic damage evaluation is deducted using these factors and the least square method and with the modification of construction time, seismic fortification intensity and portal stability. The damage of four tunnels is evaluated using the derived formula, and the results are the same with that of static and dynamic methods. It shows that the method provided in this paper is effective, reliable.