面向北京市路网特点的新型路径诱导算法及实现

结合北京市实际路网的同有特点,在基于Dijkstra算法的传统路径诱导算法的基础上,提出了新型的路径诱导算法,包含环路优先和支路优先2种路径诱导策略。引入了饱和度的概念对道路进行赋权,应用GoogleEarth技术实现了2种路径诱导。     

GPS实时地图匹配技术中缓冲区分析的研究

GPS数据如何实时地与GIS地图数据匹配已经成为GPS车辆导航系统中的关键问题之一。通过对GPS车辆导航中地图匹配问题的研究,认为可以采用误差缓冲区分析方法对GPS动态定位数据与GIS地图数据进行地图匹配。在实际应用中业已证明该方法效率高、可操作性强,有利于提高GPS车辆导航系统在应用中的精度和可靠性。     

Map-induced journey-planning biases for a simple network: A Docklands Light Railway study

A usability study was conducted to identify the most effective prototype Docklands Light Railway map for installation on trains. This comprised a series of tasks that required station finding and also planning of routes between pairs of stations, with response time and accuracy as measures of performance. In addition, subjective ratings of map design were collected via questionnaire-based evaluations, and also ranked preferences between designs. A clear best-option was easily identifiable as a result of this research. The existing design was associated with the most journey planning errors, and two of the prototypes were associated with inefficient journey choices. The latter finding suggested that respondents were using unsophisticated planning strategies that were put at a disadvantage by certain route depictions. This has wider implications for suggestions that schematic maps should maintain topographical relationships in order to facilitate appropriate journey choices, with the danger that the inevitable increased complexity of line trajectories for such designs would simultaneously reduce the ability of passengers to identify the most appropriate routes.     

耶鲁藏中国古航海图的绘制特点

耶鲁大学所藏中国古航海图的主体内容是山屿岛礁图,主要描绘山峰、岛屿的侧面形状.这是航海图一种比较原始的表示方式,其起源很早,在宋代的文献中已有记载.这种表示方法对后来的航海图有较大的影响,近代航海图上的对景图就是从山屿岛礁图演变而来.此外,耶鲁图中有4幅表示了南海诸岛的地图,他们的表示方法有与其它图幅不同的特点.     

基于Google earth的公路工程办公系统的研究和建立

该文对Google earth在公路工程建设管理中的应用做了初步的探索和研究。实践证明,建立基于Google earth的公路工程办公系统不仅技术上可行,而且Google earth的应用大大提高了工程管理人员的办公效率,减少了资源浪费。     

GOOGLE EARTH在铁路勘测设计前期工作中的应用

结合互联网上公开的地理信息数据,探讨其在铁路勘测设计前期工作中的应用,分析各种数据来源、精度、应用范围和存在问题,介绍数据使用方法。结合实际工程,分析Google Earth在不同地区辅助选线中的应用,介绍公开数字高程模型种类、精度,介绍各种地理信息系统软件。     

向量优化问题的严有效解的最优性条件

在局部凸Hausdorff拓扑向量空间中,研究了集值映射向量优化问题的严有效解.首先,在广义锥次似凸集值映射下,获得了向量优化问题的严有效解的标量化的特性,最后,获得了带广义不等式约束向量优化问题的严有效解的Lagrange型最优性条件.