文章詳目資料

電子商務學報 TSSCI

  • 加入收藏
  • 下載文章
篇名 在廣播瑁境進行與位置有關的資訊查詢
卷期 9:2
並列篇名 Search Location Dependent Data on Air
作者 林聯發黃淵科
頁次 377-400
關鍵字 索引架構資料廣播能源管理行動計算index structuredata broadcastenergy-conservingmobile computingTSSCI
出刊日期 200706

中文摘要

提供與物體位置有關的查詢服務稱為位置為基礎的服務(Location Based Services-LBSs )。提供關於LBSs的查詢,我們稱為位置有關的查詢(Location-Dependent Queries-LDQs) °LDQs的應用包括了範圍查詢(Range query)、最近者查詢(Nearest Neighbor-NN query) 、k 個最近者查詢 (K-NearestNeighbor-KNN query) 以及反向 最近者查詢(ReverseNearestNeighbor-RNNquery)等。LBSs的行動服務應用包括提 供如交通資訊與attractions等與位置相關的資訊存取以及如找尋最近的餐廳、找尋五 百公尺以內的加油站等查詢服務。雖然LDQ的問题在傳統有線以磁碟為基礎的主從 架構(disk based client-server)環境有很好的研究,目前在無線的廣播環境只處理特定 如最近者的LDQ並沒有處理同時支援各種不同類型的LDQ的問题。本論文中,我們 討論如何在無線廣播的環境有效的組織與位置相關的資料以及可以同時提供多種不同 形態的LDQ查詢的問题。無線廣播線性存取以及行動裝置必需考量節省電力的特性 使得這個問题更具挑戰性。我們針對無線廣播提出一個可適應線性存取與有效節省電 力稱為Jump-Rdnntree的索引架構與相對的LDQ查尋演算法。我們設計了大量的實 驗來驗證我們的方法,實驗結果驗證我們方法在效能方面有顯著的提升。

英文摘要

Location-based services (LBSs) provide information based on location information specified in a query. Queries that support for LBS are called Location-Dependent Queries (LDQ). LDQ contains Range query, Nearest Neighbor (NN) query, K-Nearest Neighbor (KNN) query and Reverse Nearest Neighbor (RNN) query etc. Example of mobile LBSs include location-dependent information access (e.g., traffic reports and attractions) and nearest neighbor queries (e.g., finding the nearest restaurant).While the LDQ is well studied in the traditional wired, disk-based client-server environment; it has not been tackled in a wireless broadcast environment. In this paper, the issues involved with organizing location dependent data and answering LDQ queries on air are investigated. The linear property of wireless broadcast media and power conserving requirement of mobile devices make the problem particularly interesting and challenging. An efficient data organization, called Jump-Rdnn Tree, and the corresponding search algorithm are proposed. Performance of the proposed Jump-Rdnn Tree and other traditional indexes (enhanced for wireless broadcast) is evaluated using both uniform and skew data. The result shows that Jump-Rdnn Tree substantially outperforms the traditional indexes.

相關文獻