Trip Oriented Search on Activity Tra jectory

来源 :计算机科学技术学报(英文版) | 被引量 : 0次 | 上传用户:zstzst
下载到本地 , 更方便阅读
声明 : 本文档内容版权归属内容提供方 , 如果您对本文有版权争议 , 可与客服联系进行内容授权或下架
论文部分内容阅读
Driven by the flourish of location-based services, trajectory search has received significant attentions in recent years. Different from existing studies that focus on searching trajectories with spatio-temporal information and text de-scriptions, we study a novel problem of searching trajectories with spatial distance, activities, and rating scores. Given a query q with a threshold of distance, a set of activities, a start point S and a destination E, trip oriented search on activity trajectory (TOSAT) rets k trajectories that can cover the activities with the highest rating scores within the threshold of distance. In addition, we extend the query with an order, i.e., order-sensitive trip oriented search on activity trajectory (OTOSAT), which takes both the order of activities in a query q and the order of trajectories into consideration. It is very challenging to answer TOSAT and OTOSAT e?ciently due to the structural complexity of trajectory data with rating infor-mation. In order to tackle the problem e?ciently, we develop a hybrid index AC-tree to organize trajectories. Moreover, the optimized variant RAC+-tree and novel algorithms are introduced with the goal of achieving higher performance. Extensive experiments based on real trajectory datasets demonstrate that the proposed index structures and algorithms are capable of achieving high e?ciency and scalability.
其他文献
该文从挂篮荷载计算、施工流程、支座及临时固结施工、挂篮安装及试验、合拢段施工、模板制作安装、钢筋安装、混凝土的浇筑及养生、测量监控等方面人手,介绍了S226海滨大桥
期刊
作者用球囊导管扩张术成功治疗 2例小儿先天性贲门狭窄 ,经随访 1年疗效满意。现报告如下。1 病例及方法2例患儿均为男性。 1例 9个月 ,另 1例 2岁。食后呕吐半年以上 ,消瘦
该文从挂篮荷载计算、施工流程、支座及临时固结施工、挂篮安装及试验、合拢段施工、模板制作安装、钢筋安装、混凝土的浇筑及养生、测量监控等方面人手,介绍了S226海滨大桥
期刊
包虫病是一种牧区常见寄生虫病 ,约 75 %发生在肝脏 ,位于肺者占 10 % 15 % ,以往它的治疗以外科手术为主。90年代初 ,利用经皮肝穿注射硬化剂或高渗盐水治疗肝包虫以来 ,彻
目的 观察双环铂对肿瘤细胞增殖的影响,并对其作用方式做初步分析。方法 利用MTT法检测细胞增殖抑制率;流式细胞仪和DNA琼脂糖凝胶电泳检测细胞凋亡。结果 双环铂可抑制NC
该文从挂篮荷载计算、施工流程、支座及临时固结施工、挂篮安装及试验、合拢段施工、模板制作安装、钢筋安装、混凝土的浇筑及养生、测量监控等方面人手,介绍了S226海滨大桥
期刊
针对天津滨海新区具体土地资源情况,建立了包括土壤有机质含量、表层土壤质地、土体构型、盐渍化程度、灌溉保证率和排水条件等评价因素的天津滨海新区农用地评价体系.
胃内巨大神经鞘瘤较罕见 ,现将我院经手术病理证实 1例报道如下。男 ,48岁 ,以餐后腹饱胀 ,恶心、呕吐 2 0余天入院。查体 :右上腹膨隆 ,肝剑下 10cm ,右锁骨中线肋弓下 7cm ,质