基于Geohash和动态网格的渔船轨迹相似度搜索算法  

Geohash and dynamic grid-based trajectory similarity search algorithm for fishing vessels

作　　者：梁亮 于红 刘承基[1] 高浩天 韦思学 张志涵 张如辉 LIANG Liang;YU Hong;LIU Chengji;GAO Haotian;WEI Sixue;ZHANG Zhihan;ZHANG Ruhui(College of Information Engineering,Dalian Ocean University,Dalian 116023,China;Key Laboratory of Ministry of Education for Fishery Facilities of Dalian Ocean University,Dalian 116023,China;Key Laboratory of Marine Information Technology in Liaoning Province,Dalian 116023,China)

机构地区：[1]大连海洋大学信息工程学院,辽宁大连116023 [2]大连海洋大学设施渔业教育部重点实验室,辽宁大连116023 [3]辽宁省海洋信息技术重点实验室,辽宁大连116023

出　　处：《海洋信息技术与应用》2023年第2期82-93,共12页JOURNAL OF MARINE INFORMATION TECHNOLOGY AND APPLICATION

基　　金：国家自然科学基金(31972846);辽宁省重点研发计划(2020JH2/10100043)。

摘　　要：渔船轨迹数据属于具有强时空关联的时间序列数据,相较于普通轨迹具有形状多变无规律、单条轨迹点数量不统一等特点。在使用传统相似度索引构建的查询算法中,常由于以上原因造成索引构建缓慢,查询速度下降。为解决以上问题,提出了基于Geohash和动态网格的渔船轨迹相似度搜索算法。针对渔船轨迹数据形状多变问题,基于Geohash构建可变动态网格结构,利用Geohash的唯一性所构建的网格路径范围进行轨迹查询,直接对网格路径内所包含的其他轨迹点进行计数,并加入时间维计算以保证查询轨迹与被查询轨迹处于同一时间维度;通过计算结果轨迹点数量与轨迹点总数量之间的比值解决轨迹点数量不一致的问题。为验证所提出方法的有效性,使用真实渔船轨迹数据进行实验,并与传统方法进行了比较。实验结果表明,所提出的方法能够有效提高渔船轨迹数据的索引构建速度和查询速度,为进一步数据分析提供有效的数据支撑。The trajectory data of fishing boats belongs to time series data with strong spatial and temporal correlation,which has the characteristics of variable and irregular shape and non-uniform number of single trajectory points compared with ordinary trajectory data.In the query algorithm constructed by using traditional similarity index,the index construction is often slow and the query speed decreases due to the above reasons.To solve the above problems,the similarity search algorithm of fishing boat trajectory based on Geohash and dynamic grid is proposed.For the problem of variable shape of fishing boat trajectory data,the variable dynamic grid structure constructed by Geohash is used to query trajectories by the range of grid paths constructed by the uniqueness of Geohash instead of points,and the other trajectory points contained in the grid path are counted directly,and the time dimension calculation is added to ensure that the query trajectory and the queried trajectory are in the same time dimension;The ratio between the calculated number of trajectory points and the total number of trajectory points is used to solve the problem of inconsistent number of trajectory points.In order to verify the effectiveness of the proposed method,experiments are conducted using real fishing boat trajectory data and compared with the traditional methods.The experimental results show that the proposed method can effectively improve the index construction speed and query speed of fishing boat trajectory data,and provide effective data support for further data analysis.

关 键 词：轨迹数据 相似性搜索 网格结构 Geohash编码 

分 类 号：P714[天文地球—海洋科学] U675.7[交通运输工程—船舶及航道工程]