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Lei J.,Wuhan University of Technology | Wang E.,Wuhan Institute of Technology | Wang W.,Jiangsu Province Communications Planning and Design Institute Ltd Company
Wuhan Ligong Daxue Xuebao (Jiaotong Kexue Yu Gongcheng Ban)/Journal of Wuhan University of Technology (Transportation Science and Engineering) | Year: 2016

Since there is no accurate method to calculate the fractal interpolation model of micro-texture on asphalt pavement, a hybrid optimization algorithm combined genetic algorithm (GA) and sequential quadratic programming (SQP) is put forward in the research of vertical scaling factors in the fractal interpolation model. Additional, a high-precision laser range finder, which is constituted by laser sensor and chip STM32F417, was designed to measure the asphalt pavement texture for comparison. The comparison experiment showed that the fractal interpolation model calculated by hybrid optimization algorithm is better than the model optimized by GA in terms of fitness, approximation degree of interpolation curve and the accuracy of fractal dimension. © 2016, Editorial Department of Journal of Wuhan University of Technology. All right reserved. Source

Ding X.,Hohai University | Chen Y.,Hohai University | Gu X.,Jiangsu Province Communications Planning and Design Institute Ltd Company
Journal of Hohai University | Year: 2015

Based on forecast data obtained from the China Meteorological Administration, Taiwan Meteorological Center, Japan Meteorological Agency, and Joint Typhoon Warning Center of the USA, 24-hour, 48-hour, and 72-hour ensemble forecasts of typhoon tracks of 31 typhoons over the Northwestern Pacific in 2013 were conducted using the weighted bias-removed ensemble mean method. Error analysis indicates that the results of ensemble forecasts using the fixed training method with a constant weighting factor are quite sensitive to the selection of training samples, showing significant fluctuation of error for different training samples, while the error of ensemble forecasts using the moving training method with a variable weighting factor shows a declining trend with the increase of the number of training samples and tends to be stable when the number reaches 40. Comparisons show that twin typhoons in the training period have a large influence on the forecast accuracy, and the accuracy is significantly increased by removal of the influence of twin typhoons. Based on comprehensive comparisons of forecast results of 2013's typhoon tracks, the moving training method with 40 training samples and without consideration of twin typhoons in the training period is recommended. ©, 2015, Editorial Office of Journal of Hohai University (Nature Sciences). All right reserved. Source

Li L.,Jiangsu Province Communications Planning and Design Institute Ltd Company | Liu S.,Hohai University | Xu X.,Hohai University | Zhang Y.,Hohai University
Advances in Science and Technology of Water Resources | Year: 2015

In order to understand dynamic characteristics of the new-type flexible retaining walls constructed with soilbags, small-scale shaking table model tests were conducted on retaining walls constructed with soilbags filled with natural sands. The effects of three elements of earthquakes, input accelerations, vibration frequencies, and vibration durations, as well as the size of soilbags, on the retaining walls were investigated, and change patters of horizontal displacements, dynamic earth pressures, and accelerations were analyzed. The results show that displacements of retaining walls and pressure coefficients of dynamic earth increase with the increase of input accelerations and the decrease of vibration frequencies, while the acceleration response increases with the increase of both input accelerations and vibration frequencies. However, the effects of vibration durations on dynamic characteristics are relatively small. In addition, compared with retaining walls constructed with normal-size soilbags, the seismic performance of retaining walls constructed with larger bags is slightly poorer. However, larger soilbags can be used in areas with lower seismic requirements or projects with tight schedules because of their ease of construction and high efficiency. ©, 2015, Editorial Office of Journal of Hohai University (Nature Sciences). All right reserved. Source

Xie R.,Hohai University | Xie R.,Fujian Normal University | Pang Y.,Hohai University | Bao K.,Jiangsu Province Communications Planning and Design Institute Ltd Company
Environmental Science and Pollution Research | Year: 2014

Currently, the poor water quality in Taihu Lake is a major problem in China, so pollution control in the upstream areas has become a government priority. In Jiangsu Province, pollution emissions around the western areas of Taihu Lake, including Changzhou Municipality and Yixing City, need to be highly restricted, and calculating the water environmental capacity is important if pollution is to be reduced. In this study, 19 control units in these areas were established, and a 0-D mathematical model was used to calculate the water environmental capacity. For three important control units with important cross sections, a 1-D model was established to redress the results. Finally, the total maximum monthly loads of each control unit were obtained using temporal allocation principles. The results suggested that (1) the total pollution control of chemical oxygen demand was 58,894.2 tonnes per annum (t a-1), with ammonia nitrogen, total nitrogen, and total phosphorus amounting to 3,808, 6,054.6, and 386.6 t a-1, respectively; (2) water environmental capacity per unit water area in the ambient control units was smaller than that in the middle control units; and (3) the largest water environmental capacity was in June, and the smallest capacity was in December. The study provides important information for local governments, which will enable them to implement pollution control strategies that will improve the water quality in Taihu Lake. © 2014 Springer-Verlag Berlin Heidelberg. Source

Wang W.,Nanjing Southeast University | Huang H.,Nanjing Southeast University | Zhao F.,Jiangsu Province Communications Planning and Design Institute Ltd Company
Tumu Gongcheng Xuebao/China Civil Engineering Journal | Year: 2015

The experiments on bonding behavior at the interface of GFRP plate and cast-in-place concrete were conducted. A predicted model for the interfacial debonding loads and relationship of interfacial shear stress and slip was proposed. The test results show that the failures of specimens based on the wet bonding technique appear in the mortar layer and the fine aggregates were found to be bonded on the debonding GFRP plate. The initial placement time of concrete, curing time of concrete and interfacial type influence the debonding loads significantly. The maximum debonding load is obtained when the initial placement of concrete is 30 minute. The debonding loads increase with the curing time of concrete. The calculated results by the proposed model agree well with the experimental results, which show that the debonding loads and relationship between local interfacial shear stress and slip can be effectively predicted. ©, 2015, Editorial Office of China Civil Engineering Journal. All right reserved. Source

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