於無所不在計算( Ubiquitous Computing )所提出的概念中，我們可以在任何時間，任何地點以任何方式透過任何形式的設備來取得計算資源，而透過設備的精確定位及智慧物件的使用，使得無所不在的系統更具有情境感知(context awareness)的特性，可以依照使用者所在的位置及周邊的環境狀況，在適當的時機、地點提供最適合使用者的資訊。
本論文利用個人數位助理(Personal Digital Assistant, PDA)、無線射頻識別 (Radio Frequency Identification, RFID)標籤讀取機與802.11無線網路傳輸設備，設計並實作一個稱為U-Guide的無所不在的導覽系統(Ubiquitous Guiding System)，目的是建立一個有別於傳統的導覽系統，可以在任何時間、任何地點取得適當的資訊，並適時的提供給使用者。U-Guide整合兩種現存的技術 : APS (Ad-hoc Positioning System) 定位與 RFID 標籤識別技術，並融入另行設計出的兩種新技術：最遠標籤傳送，標籤輔助定位。最遠標籤傳送的目的是在僅有少數設備具有 RFID 標籤讀取機的情況下，讓導覽設備透過多跳(multi-hop)無線電傳輸方式在遠距離即可獲得智慧物件的標籤資訊。而標籤輔助定位則是於標籤中事先寫入位置座標資訊，當具有RFID標籤讀取機的導覽設備讀取到標籤資訊後，就可以準確知道本身所在的位置，同時可以將此一座標資訊傳送給其他導覽設備以協助定位的進行。在最遠標籤傳送技術方面，我們進行實驗以驗證標籤資訊多跳無線傳輸能夠正確的進行；而在標籤輔助定位方面我們也做了相關的測試，以驗證U-Guide系統定位的精確度。我們並以植物園導覽為例，舉例說明如何使用U-Guide系統，以展現U-Guide系統的功能與效果。

In ubiquitous computing, we can get computing resources at any time and any place. In particular, ubiquitous computing endows users with the context awareness capability by providing them the right information at the right place and right time. In this paper, we use the PDA, RFID and 802.11 instruments to design and implement U-Guide, a ubiquitous guiding system. U-Guide integrates two existing technologies, ad-hoc positioning system (APS) and Radio Signal Strength Indication (RSSI) positioning, with two new techniques: farthest tag forwarding and tag-assisted positioning. There are two types of devices: guide nodes and normal nodes. A guide node is equipped with a RFID reader, while normal node is not. When a guide node reads a tag, it broadcast the tag information. Farthest tag forwarding makes the node in the guide node’s transmission range and farthest from the guide node have the highest probability to forward (relay) the tag information. This can reduce the number of tag information relays dramatically. With tag-assisted positioning, by pre-establishing position information on the tag, we make a guide node perceive its position once it reads a tag. We have implemented U-Guide and conducted positioning test to examine U-Guide’s functions and capabilities.

[1]. Paramvir Bahl , Venkata N Padmanah han．”RADAR：An in—building RF based user
location and tracking system”．In：Proceedings of lnfcom"2000，Tel Aviv，Israel：IEEE Computer and Communications Societies。2000；2：775～584
[2]. Lewis Girod , Deborah Estrin ”Robust Range Estimation using Acoustic and
Muhimodal Sensing”．In：Proceedings of lEEE卅RsJ lntemational Conference on
Intelligent Robots and Systems(1R0SD1)，Maui，Hawaii，USA：1EEE Computer
Society．2001；3：1312～1320
[3]. A Harter , A Hopper , P Steggles et a1”The anatomy of a context—aware application” In：Proceedings of Mobile Computing and Networking (MOB1COM99)，Seattle，WashinIgton，USA：ACM Press，1999：59～68
[4]. Nirupama Bulusu , John Heidemann , Deborah Estrin ”GPS-less Low Cost
Outdoor Localization for Very Small Devices”IEEE Personal Conlmunieations，2000；7(5)：28～34
[5]. Chris Savarese , Jan M Rabaey , Jan Beute1 “Locationing in Distributed Ad—Hoc wireless sensor network” In：Proceedings of IEEE Intemational Conference on Acoustics，Speech，and Signal(ICASSP "01)，Salt1,ake，USA：IEEE Computer Society，2001；4：2037～2040
[6]. Dragos Niculescu , Badri Nath. “Ad Hoc Positioning System (APS).”
GlobalTelecommunications Conference, 2001. GLOBECOM ''01. IEEE Volume 5, 25-29 Nov. 2001 Page(s):2926 - 2931 vol.5
[7]. Tian He , Chengdu Huang , Brian M. Blum , John A. Stankovic , Tarek Abdelzaher
“Range-Free Localization Schemes for Large Scale Sensor Networks.”
[8]. P. J Brown, J. D. Bovey, and X. Chen, “Context-Aware Applications: from the Laboratory to the Marketplace,” IEEE Personal Communications, pp. 58-64, 1997. 43
[9]. J. W. Chen, “A Ubiquitous Information Technology Framework Using RFID to Support Students’ Learning,” Proceedings of the 5th IEEE International Conference on Advanced Learning Technologies, pp. 337 – 342, 2005.
[10] Z. Cheng, S. Sun, M. Kansen, T. J. Huang, and A. G. He, “A personalized ubiquitous education support environment by comparing learning instructional requirement with learner''s behavior,” Proceedings of the 19th IEEE International Conference on Advanced Information Networking and Applications, pp.567 – 573, 2005.
[11] OpenNETCF 網站 : www.opennetcf.org
[12] C. Cortez, M. Nussbaum, X. Lopezw, P. Rodrguze, R. Santelices, R. Rosasw, and V. Marianovz, “Teachers'' Support with Ad-hoc Collaborative Networks,” Journal of Computer Assisted Learning, pp. 171 – 180, May 2005.
[13] N. Davies, K. Mitchell, K. Cheverest, and G. Blair, “Developing a Context Sensitive Tourist Guide”, First Workshop on Human Computer Interaction with Mobile Devices, GIST Technical Report , 1998.
[14] 陳惠貞 編著，Visual C#.NET 程式設計，學貫行銷股份有限公司，2002
[15] S. Jean, “Ubiquitous computing goes mobile,” Proceedings of ACM SIGMOBILE Mobile Computing and Communications Review, Volume 5, Issue 3, pp. 32-38 July 2001.
[16] L. D. Chou, C. C. Lee, M. Y. Lee, and C. Y. Chang, “A tour guide system for mobile learning in museums,” Proceedings of the 2nd IEEE International 2004 Wireless and Mobile Technologies in Education Workshop, pp.195 – 196 2004.
[17] S. Long, “Rapid Prototyping of Mobile Context-aware Applications: The Cyberguide Case Study.” Proceedings of 2nd ACM International Conference on Mobile Computing and Networking (MobiCom''96), November 1996.
[18] WJ Communication 網站 : www.wj.com 44
45
[19] M. Weiser, “The Computer for the Twenty-First Century, Scientific American,” pp. 94-104, March 1991.
[20]M. Weiser, “Some Computer Science Issues in Ubiquitous Computing.” Communications of the ACM, Volume. 36, pp. 74 – 84, July 1993.
[21] R. Weinstein, “RFID: a technical overview and its application to the enterprise” IEEE IT Professional Volume 7, Issue 3, pp. 27 – 33, May-June 2005.
[22] 蘇雍智，「以無線識別機制設計無所不在的數位學習環境」，國立中正大學，碩士
論文，民國九十四年七月
[23] 鄒植汎，「博物館PDA導覽系統之評估與建構」，國立清華大學，碩士論文，民國
九十五年八月
[24] 黃國禎，「U-Learning 時代的來臨與挑戰」，2005年10月
[25] 賴鼎陞，高淑惠，黃雅慧，「博物館數位導覽系統建置與使用者評估」
[26] 曹浩諭，「個人數位導覽於故宮博物院的學習應用」，宏碁數位藝術中心 Acer Digital
Art Center
[27] Trimble (2006). All About GPS. http://www.trimble.com/gps/