基于CRUISE的纯电动汽车性能仿真

为建立纯电动汽车的动力系统结构,提出了动力系统的匹配设计方法,在理论设计和工程分析的基础上,对其电机、电池以及传动比进行了匹配。应用CRUISE软件搭建模型进行仿真研究,证明匹配的结果满足设计要求,表明这种方法可行有效。     

基于等值线搜索带的地磁匹配算法

针对TERCOM算法在地磁匹配应用中存在的不足,提出了基于等值线搜索带的改进匹配算法,将地磁基准图上的匹配搜索区域缩小到航迹起始点地磁测量值对应的地磁场等值线附近区域,从而减少匹配搜索时间和计算量.仿真实验结果表明,该算法在保证匹配精度的前提下,能够有效降低匹配计算时间,提高匹配算法的实时性.     

Self-organizing map based quality assessment for resistance spot welding with featured electrode displacement signals

To classify the quality of the resistance spot welding process, a relationship between the welder electrode displacement curve characteristics and the weld shear force has been explored. Eleven statistical features of the displacement signals are extracted to represent the welding quality. Self-organizing map (SOM) neural networks have been employed to discover their quantitative relationship. In order to identify the influence of various displacement curve features, all of the available combinations have been used as inputs for SOM neural networks. Further we analyze the impact of each feature on the classification results, yielding the best quality-indicative combination of characteristics. There is no determinant relationship between the welding quality and the level of expulsion rate. The quality of welding is most impacted by the maximum electrode displacement, the span of welding process and the centroid of the electrode displacement curve. The experiments show that SOM is feasible to assess the welding quality and can render the visualized intuitive evaluation results.     

高压富水断层超前预注浆快速施工技术研究

超前注浆作为处理高压富水断层的主要手段,能够有效地达到“封堵地下涌水、加固破碎围岩、控制施工风险、保护周边环境”的目的,但由于超前注浆施工周期长,工程投入大,因而对于复杂地层往往不能作为首选方案。本文打破传统超前注浆设计理念,提出信息化注浆设计创新理念,使注浆更具有针对性,在保证注浆效果的基础上减少工程数量,通过对注浆机械配套、施工方法、注浆材料及效果检查评定手段等方面的系统研究,实现了高压富水断层超前注浆快速施工。     

Novel Chaotic Fragile Watermarking Algorithm for Image Authentication

Taking full advantage of the randomicity of chaotic system and its extreme sensitivity to the initial value, a new chaotic fragile watermarking algorithm is proposed. In the algorithm, the location key is looked as a logistic chaotic initial value for iteration to create a location matrix. According to this location matrix, a mapping image is generated and the embedding location of watermarking in image blocks is identified. Then, the watermarking sequence, which is related with the mapping image blocks and generated by H6non chaotic map, is embedded into the least significant bit (LSB) of the corresponding location in each block. Since the image content and watermarking are staggered, the algorithm has a higher security. Simulation results showed that the algorithm can detect and locate the tamper in watermarked images with an accuracy of 2 x 2 block pixels. At the same time, the watermarking images has good invisibility, and the original image is not required when extracting watermarking.     

车辆导航系统中地图匹配的研究

分析影响地图匹配实时性、鲁棒性和匹配精度的因素,针对常用投影法,概率统计法、相关性算法、基于网络拓扑以及基于曲线拟合的地图匹配算法进行描述,并针对基于D-S证据推理的地图匹配算法.匹配误差比较大的转弯路段,平行路段以及立交桥路段进行分析并且给出匹配漉程.通过实验仿真表明本文算法对复杂路口有较好的适应性和较高的匹配精度.     

青藏铁路GIS地图显示风格配置组件的设计及实现

地图显示风格一般是以文件方式存放的,而且,不同地理信息系统软件其风格配置文件是不一样的,并且是不透明的,因此,不利于地图显示风格的传播及维护.探讨使用数据库方式,配置地图的显示风格,这样空间数据和地图的显示风格都可以统一的保存到数据库中,以数据库的方式管理和维护,以提高地图显示风格的统一性和可维护性.     

导航电子地图增量更新方法研究

目前车辆导航系统中通常以阶段性的更换数据的方式来更新地图数据,这一方法已不能满足导航电子地图数据库对数据现势性的要求。基于邻接表的路网拓扑结构,采用增量更新的方法,实现了中心端和车载端的导航电子地图的更新,并在更新过程中对拓扑关系进行了维护,避免了对整个路网的拓扑重构,并对该方案进行了试验和分析。     

交通路网数据自动增量识别与技术更新

道路网络数据是进行交通分析研究、规划设计的基础,为保证数据的现时性,时间和版本的继承性,交通部门需要参考不同来源数据对路网进行更新,文中针对这种专业现状和需求,提出了1种以各种来源新采集路网矢量数据为参考,进行快速、准确自动增量识别及增量更新的技术方法,从而大大减轻路网数据每年更新维护的时间与人力投入。     

基于供需平衡的公路网评价方法研究

为了分析公路交通供需之间的适应程度,按性质和功能对区域公路交通需求和供给进行分类,分别从高速公路、一级公路和双车道公路三方面对公路交通需求和供给进行量化分析,分析各等级公路每个车道的适应交通量,研究各参数的计算方法,引入路网供需匹配度的评价指标,构建路网供需匹配度的评价模型,提出评价标准,为地区公路网建设规模的合理性评价提供有益的借鉴.