基于布朗桥概率模型的定向移动  

Probability Model of Directed Movements Based on Brownian Bridge

作　　者：尹章才[1] 何晓蓉[1] 张晓盼[1] 黎华[1] 

机构地区：[1]武汉理工大学资源与环境工程学院,湖北武汉430070

出　　处：《测绘科学技术学报》2012年第6期397-400,共4页Journal of Geomatics Science and Technology

基　　金：国家自然科学基金面上项目(41071283);中央高校基本科研业务费专项资金项目(2012-IV-097);国家大学生创新创业训练计划项目(2012-38)

摘　　要：在已知起止点时间和位置及最大速度条件下,针对移动对象的时空不确定性,引入布朗桥并提出一种新的定向移动时空概率模型。首先,根据已知条件计算移动对象在任意时刻t的可达空间范围,即样本空间;然后,建立移动速度标准差到布朗运动常系数的映射关系;最后,以布朗桥在时刻t的概率分布为基础,通过样本空间的裁剪及归一化处理获得定向移动在时刻t的概率分布。结果表明:随最大速度的增大,提出的概型较已有概型在方差方面具有稳定性。When the location of an agent at one time and then again at another time, and its maximum velocity are known, the space-time information of the agent is uncertain. Brownian Bridge was introduced into the prob- ability model o{ directed movements to approach the uncertainty in time geography. Firstly, according to that knowledge, the accessible area at any time t was calculated, that is to say sample space. Secondly, the mapping relationship from standard deviation of directed velocity to constant coefficient of Brownian motion was built＇ up. Finally, on the basis of Brownian Bridge＇ s probability distribution at t, through cutting based on the sample space and normalization, the probability distribution of directed movements at t was got. The results showed that variance of the probability model suggested in this paper tended towards stability in relation to existed probability model, with increasing the maximum velocity.

关 键 词：概率时间地理 布朗桥 定向移动 棱柱体 方差 

分 类 号：P208[天文地球—地图制图学与地理信息工程]