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1.
Due to the rapid urban construction, commercial districts in Beijing are constructed near subway stations. Good landscape greening plays a crucial role in improving the environmental quality of the area around subway stations. At present, there are few studies on the landscape greening around subway stations adjacent to commercial districts. In this paper, field research on landscapes in the commercial district around seven typical subway stations was conducted to monitor real-time noise and crowd activities and analyze the utilization status of street parks, in order to provide a reference for the construction and renovation of the landscape greening around subway stations near commercial districts.  相似文献   

2.
A wheeled vehicle to be fitted with common rubber - tire do not adapt to the desert area because of the wheel slip sinkage. It is important for improving the mobility of vehicle in sand to develop a new running gear of vehicles . Based on the mathematical models and mechanical models for interaction effect between wheel and sand. the influence on the interaction effect between running gear of vehicles and sand on traction performance are analyzed by using the theory of granular limit equilibrium. The results show that the interaction modes between wheel and sand is charged and the mobility of vehicle in sand is improrld.  相似文献   

3.
Particulate matter has become one of the major pollutants causing environmental pollution and affects human health. Motor vehicle particulate matter emissions accounted for more than 60% of the pollutants. At present, research on motor vehicle particulate matter emissions has inadequate systematic control strategies. This paper first analyzes the draw of the motor vehicle particulate matter formation mechanism and influencing factors. According to the statistics of the China Motor Vehicle Pollution Prevention Annual Report, mathematical models of the number of cars, the number of low speed motor vehicles and the number of motor vehicles with particulate matter emissions are presented using MATLAB, and the total amount of motor vehicle particulate emissions in the next five years is predicted. The results show that the motor vehicle particulate emissions increases every year and reached 1.032 2 million tons in 2015. Low-speed vehicle number PM emissions will gradually be reduced slowly, mainly influenced by national policies. Finally, according to the analysis and forecasting results, an effective motor vehicle particulate matter emission control strategy is put forward.  相似文献   

4.
智能视频分析的车辆异常行为检测方法   总被引:1,自引:0,他引:1  
为验证公司自主研发的呋喃它酮代谢物化学发光微粒子检测试剂盒的检测效果,用化学发光微粒子免疫法和高效液相色谱串联质谱法对猪肉、鸡肉、鱼肉、虾4个样品中呋喃它酮代谢物残留量进行检测,比对两种方法试验结果间的差异。结果表明,使用直接竞争CLIA试剂盒检测动物性食品中呋喃它酮代谢物残留量,其特异性强,灵敏度较高,在猪肉、鸡肉、鱼肉、虾样品中0.2、0.4、0.8μg/kg 3个水平的加标回收率均在94.0%~101.0%之间,变异系数均小于15%,最低检测限分别为86.24、84.09、84.51、88.12 ng/kg;此方法与高效液相色谱串联质谱法检测实际样品的阴、阳性判断结果一致,其结果稳定、可靠,可满足现场快速检测动物组织中呋喃它酮代谢物残留的要求。  相似文献   

5.
How to remove the background , to eliminate the misdetection caused by vehicle changes road or it covers the detection window of the road detected partly, is a big problem to be handled in vehicle detection system.This paper presents an improved frame-difference method based on Video,and describes how to detect and count vehicles in detecting zone dynamically.With this method, we can count the vehicles passing by accurately, collect the traffic flow of each roadway reliably.We provide real-time traffic parameters for the ITS.  相似文献   

6.
A fuzzy multi-objective control strategy is proposed for parallel hybrid electric vehicles (PHEV). By the concept of motor equivalent fuel consumption, the overall vehicle fuel economy and the corresponding emissions can be treated as the optimization objectives. Then a minimum average weighted deviation method is designed to find the Pareto optimal solution with considering the variations of objective preference in different district. The simulation on ADVISOR reveals that, compared with the rule based control strategy (RBCS), with the premise that there is no loss to power performance, the proposed fuzzy multi-objective control strategy (FMCS) not only improves fuel economy and emission level but also maintains battery SOC within its operation range more effectively.  相似文献   

7.
In order to help tourists choose satisfying scenic spots, content hotels, convenient lines and convenient vehicles, vehicle monitoring control and scheduling management system in a scenic area is presented, which dispatches vehicle by appointments and the statistic of tourists at a sight spot and recommends the tour line by broadcasting in vehicle. Vehicle monitoring control and scheduling management system in a scenic area, a integrative vehicle management system, is an integration of GPS, GIS, trunked radio system, a management system of booking room and a tourist statistic system at a sight spot.  相似文献   

8.
In order to assess the vibration performance of all terrain vehicles, a half vehicle model with 10 degrees of freedom was built. The model was solved using the time domain method. Road surface irregularity excites the model and was generated by a trigonometric function. Based on this model, the beaming of the frame was analyzed. The results show that the first beaming and second beaming influence the vibration significantly. As a result, a half vehicle model that includes the first two beamings of the frame can satisfy the vehicle vibration analysis precision requirements. Driver ride quality was evaluated according to ISO2631 1.  相似文献   

9.
为了建立用于机动车尾气排放测算的行驶周期,利用便携车载尾气采集装置(PEMS)系统和GPS装置进行了大量的机动车尾气排放和驾驶活动数据采集,并对数据进行了预处理,提出了短行程的评价标准,给出了最优短行程自动搜索的2种启发式算法(遗传算法(GA)和离散同步扰动随机逼近(DSPSA)),对建立的行驶周期进行了预测尾气排放总量的有效性验证。结果表明:2种启发式算法均能有效地解决行驶周期自动建立问题,GA算法优化得到的行驶周期更有代表性,该行驶周期能以相对较小的误差预测尾气排放总量。建议将GA算法作为开发其他城市的行驶周期的算法工具。  相似文献   

10.
Hybrid electric vehicle (HEV) is a mixture of electric vehicle and conventional vehicle, which has the merits of reducing exhaust gas and the consumption of gasoline HEV is the new development way of automobile industry. This paper introduces HEV, and discusses the essential framework of HEV drive system,the basic types of the electrical drive and their features and the present state of the development at home and abroad.Some key technologies are also proposed which determine the drive and control performance of HEV.  相似文献   

11.
This essay applies fuzzy caculus to the multi-information of automatic highway operation,and sets the safe motion mode for vehicles. After the systematic reasoning of expert,this model can be used to adjust the controllable parameters in vehicle motion toAvoid traffic accidents and improve the capability of passage.  相似文献   

12.
The purpose of a parallel hybrid electric vehicle(PHEV) is for the best energy distribution between internal-combustion engine(ICE) and electric motor though the appropriate control strategy.It can not only keep the advantage of the ultra-low emission of electric vehicles(EV),but also take advantages of the hyperbaric energy of ICE.Simulation model for PHEV is built based on CRUISE,an auxiliary control strategy is designed,and then parameter simulation study on the control strategy is performed.The simulation results show that according to the different control requirements,the vehicle performance can be improved by adjusting!the corresponding control parameters.  相似文献   

13.
Taking the hybrid electric vehicle as the investigation subject, this paper studies the remote data acquisition, supervisory control and redisplay system of the hybrid electric vehicle fault diagnosis. The system gathers the simulate CAN BUS data through serial ports by the data acquisition device and send data to the remote web servers by the GPRS wireless communication module. For the demands and features, the paper makes the module selection and design the hardware of lower computer ,and the software on the host computer and lower computer. It takes several notebooks as the simulate vehicle date emission source to make an experiment, achieving the function of wireless data transfer, data acquisition, supervisory, redisplay for multi hybrid electric vehicles at the same time, and protocol setting up. Especially the function of wireless data transfer and protocol setting up, make a big progress on the common use and convenience of fault diagnosis system.  相似文献   

14.
随着各地城市化进程的不断推进,自然资源及城市问题之间的矛盾也日益凸显。虽然各地农业发展仍保持增长态势,但是与农业息息相关的水资源和土地资源匹配程度略显不足。本研究利用全市16个市辖区2009—2015年的水资源与耕地资源、农业经济状况为指标变量,首先计算时空不同维度上的水土匹配程度,然后将各区的水土匹配情况与农业经济做相关性分析。结果显示:全市的水土匹配系数在2012年达到一个小高峰后逐年减小,总体呈现条带状分布,区际间的水土匹配系数也有明显差异,东部整体水平好于西部,南部好于北部地区,水土匹配状况较好的地区有大兴、顺义和通州,而城六区略差;并且水土匹配系数与农业经济呈现统计学意义上的正相关。本研究中给出的水土匹配情况的技术框架简单可行,并且其结果也可为各地农业未来发展的进一步优化调整提供科学依据。  相似文献   

15.
This paper proposes a model framework, which describes the function requirements and the common characterstics of vehicle transport management. With the frame, a computer vehicle transportation managerment information system(QCMIS)is in troduced here and it has already been put into practice. The key technical points is also explained in the paper.  相似文献   

16.
针对传统两级车辆路径优化过程,存在的精度不高,收敛时间过长的问题,提出一种基于Q学习理论和差分进化的Memetic算法。首先,对两级车辆路径优化问题进行研究,利用最优分割法获得第一级配送方案,以此确定中转站配送数量,然后求解第二级多配送中心车辆路径问题配送方案,获得两级优化问题的总里程及总配送车辆数量;其次,针对第二级MDVRP配送方案求解,利用Q学习理论和差分进化算法,设计新的Memetic算法,来实现对多配送中心车辆路径问题配送方案的全局优化;最后,通过仿真验证了所提算法的有效性。  相似文献   

17.
Based on the dynamic action between vehicles and pavement, a simplified model of vehicle dynamic loading caused by surface evenness was established. This research made it possible to find a Asphalt Pavement Rutting Prediction method based on the theory of visco elasto plasticity which is the basic theory of the dynamics, and finite element method (FEM). Asphalt pavement rutting was calculated and predicted, and the factors influencing rutting were analyzed and calculated. The good agreement between the calculation results and the testing road data indicate that the rutting prediction method is reasonable and reliable.  相似文献   

18.
Owing to increasingly strict emission regulation, gasoline properties not only satisfy the needs of high performance for the engine, but also attain the requirement of vehicles exhaust control. The gasoline from gas stations around China is sampled and its properties are analyzed. The distribution of gasoline quality in different zones is listed. At the same time, the difference of properties between domestic and oversea gasoline is compared. After establishing the emission model of the engine, the reference value of vehicle emissions in different zones is obtained. At last, some measurements are proposed to reduce the emissions: improving gasoline quality and controlling the related parameters for engine according to the distribution of gasoline properties.  相似文献   

19.
With the city development and construction, ecological corridor has become one of the most attractive areas in urban districts. Ecological corridor has produced not only ecological benefits, but also economic benefits and social benefits, especially banded ecological park. By analyzing the impact of Fen River Park on leisure space, living space, communication space, commercial space of Taiyuan, and expounding shortcomings of constructing Fen River Ecological Corridor, countermeasures and suggestions were put forward.  相似文献   

20.
Through investigating colors of Xuzhou City, combining with color planning practices in domestic and foreign cities, current colors and characteristics of main urban districts of Xuzhou City were analyzed, overall orientation and design concept of city color were explored, the overall framework of regional building colors and the zoning planning were proposed, to give new concepts for the future city color planning and design.  相似文献   

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