目前地理資訊系統皆使用關連式資料庫儲存及處理地理資訊，使用資料庫最大的好處是它能有效率的操作地理資訊。然而，系統的互通性卻無法兼顧，因為地理資訊的高異質性及複雜結構，加上沒有標準化的表達格式，使得系統間交換資料及結構的工作變得困難。地理標示語言(Geography Markup Language, GML)是基於可擴展標示語言(eXtensible Markup Language)發展出的地理資訊描述語言，它是公認用以表示、儲存及交換地理資訊的標準，且已被視為是一種可以提高互通性的方法。僅管如此，目前仍沒有地理資訊系統單純採用地理標示語言為核心，並直接操作地理標示語言標示的資訊。原因可能是目前為XML或GML發展的 工具並不成熟且效能不佳所致。我們的研究即是發展出高效能的GML工具，並於全球資訊網上實現一個以地理標示語言為核心的地理資訊系統，並探討這種新的地理資訊系統的設計是否可以激發出新型態地理資訊被儲存及操作的方式。

更進一步說明，我們延伸既有的標準化的XML處理工具，使其能處理地理資訊，另外，為了提升處理工具的效能，我們發展了一個XML/GML文件的過濾器，該過濾器實際上是一個小型的搜尋引擎，用以快速的判定欲檢索的資訊位置，使得沒有用的資訊能被過濾掉，進而有效提升檢索效能，對於處理大的文件特別有幫助。我們同時提出最佳化該過濾器的效能的方法，我們的實驗證明該過濾器的確能提升XML/GML處理工具約10倍的檢索效能。

Most geographic information systems (GISs) use relational databases to manipulate information efficiently. They however suffer from interoperability issues because they need to expend significant effort mapping heterogeneous geographic information, which may have complicated structures, into relational data models, and vice versa. Geography Markup Language (GML) is regarded as a standard for expressing, storing, and exchanging geospatial data, and has been applied to help solve interoperability problems. Interestingly, no GIS has been built on native XML/GML technologies so far. There are two possible reasons for this: current XML processors are incapable of processing geospatial information, and they are inefficient in manipulating large XML documents. In this paper, we resolve these two difficulties and move forward to realizing GML-native Web-based geographic information systems.

Specifically, we develop an XML/GML prefilter for enhancing query performance in the GML-native Web-based GISs as well as other generic XML processors. The prefilter is an efficient, small-scale, lightweight, minimal intrusive, and transparent technique for improving XML processing in large documents. The prefilter essentially uses a tiny search engine to locate interesting fragments in the source XML documents by approximately executing the user's queries. The interesting fragments and some necessary structural information are gathered into a candidate-set XML document that is returned to the XML applications for further processing. The prefilter can either reduce computational resources or lower query execution time. Depending on the nature of user queries, the enhanced query processors can reach ten-fold performance improvement, while an overhead of about 10~15% would incur for answering queries that return almost the entire documents.

[1] Ashraf Aboulnaga, Alaa R. Alameldeen, and Jeffrey F. Naughton. Estimating
the selectivity of xml path expressions for internet scale applications. In
VLDB ’01: Proceedings of the 27th International Conference on Very Large
Data Bases, pages 591–600, San Francisco, CA, USA, 2001. Morgan Kaufmann
Publishers Inc. [cited at p. 40, 42]
[2] Sihem Amer-Yahia, Laks V. S. Lakshmanan, and Shashank Pandit. Flexpath:
flexible structure and full-text querying for xml. In SIGMOD ’04: Proceedings
of the 2004 ACM SIGMOD international conference on Management
of data, pages 83–94, 2004. [cited at p. 79]
[3] Rudolf Bayer. Binary b-trees for virtual memory. In E. F. Codd and A. L.
Dean, editors, Proceedings of 1971 ACM-SIGFIDET Workshop on Data
Description, Access and Control, San Diego, California, November 11-12,
1971, pages 219–235, 1971. [cited at p. 18]
[4] V’eronique Benzaken, Giuseppe Castagna, Dario Colazzo, and Kim
Nguyˆen. Type-based xml projection. In VLDB ’06: Proceedings of the
32nd international conference on Very large data bases, pages 271–282,
2006. [cited at p. 70, 81]
[5] Scott Boag, Don Chamberlin, Mary F. Fern’andez, Daniela Florescu,
Jonathan Robie, and Jerome Simeon. Xquery 1.0: An xml query language,
w3c recommendation 23 january 2007. Technical report, W3C -World Wide
Web Consortium, January 2007. [cited at p. 3, 20]
[6] Omar Boucelma and Franc﹐ois-Marie Colonna. Gquery: A query language
for gml. In Massimo Rumor Elfriede Fendel, editor, 24th Urban Data Management
Symposium, pages 23–32, Chioggia, Italie, 27–29 Octobre 2004.
UDMS 2004. [cited at p. 3]
[7] Tim Bray, Jean Paoli, C. M. Sperberg-McQueen, Eve Maler, and Francois
Yergeau. Extensible markup language (xml) 1.0 (fifth edition), w3c recommendation
26 november 2008. Technical report, W3C - World Wide Web
Consortium, 2008. [cited at p. 1]
[8] St’ephane Bressan, Barbara Catania, Zo’e Lacroix, Ying Guang Li, and
Anna Maddalena. Accelerating queries by pruning xml documents. Data
Knowl. Eng., 54(2):211–240, 2005. [cited at p. 32, 35, 51, 54, 56, 79]
[9] Kaushik Chakrabarti, Minos Garofalakis, Rajeev Rastogi, and Kyuseok
Shim. Approximate query processing using wavelets. The VLDB Journal,
10(2-3):199–223, 2001. [cited at p. 54]
[10] Don Chamberlin, Daniela Florescu, Jim Melton, Jonathan Robie, and
Jerome Sim’eon. Xquery update facility 1.0, w3c candidate recommendation
1 august 2008. Technical report, W3C - World Wide Web Consortium,
2008. [cited at p. 75]
[11] Chin-Lung Chang, Yi-Hong Chang, Tyng-Ruey Chuang, Steve Ho, and
Feng-Tyan Lin. Bridging two geography languages: Experience in mapping
sef to gml. In Proceedings GML Dev Days: 2nd GML Developers
Conference, 2003. [cited at p. 61]
[12] Qun Chen, Andrew Lim, and Kian Win Ong. D(k)-index: an adaptive structural
summary for graph-structured data. In SIGMOD ’03: Proceedings of
the 2003 ACM SIGMOD international conference on Management of data,
pages 134–144. ACM, 2003. [cited at p. 54]
[13] Shu-Yao Chien, Zografoula Vagena, Donghui Zhang, Vassilis J. Tsotras,
and Carlo Zaniolo. Efficient structural joins on indexed xml documents. In VLDB ’02: Proceedings of the 28th international conference on Very Large
Data Bases, pages 263–274, 2002. [cited at p. 40, 53]
[14] Chin-Wan Chung, Jun-Ki Min, and Kyuseok Shim. Apex: an adaptive path
index for xml data. In SIGMOD ’02: Proceedings of the 2002 ACM SIGMOD
international conference on Management of data, pages 121–132. ACM,
2002. [cited at p. 54]
[15] James Clark and Steve DeRose. Xml path language (xpath) version 1.0,
w3c recommendation 16 november 1999. Technical report, W3C - World
Wide Web Consortium, 1999. [cited at p. 3, 8]
[16] Jose Eduardo C’orcoles and Pascual Gonz’ alez. A specification of a spatial
query language over gml. In GIS ’01: Proceedings of the 9th ACM international
symposium on Advances in geographic information systems, pages
112–117, 2001. [cited at p. 20]
[17] Jose Eduardo C’orcoles and Pascual Gonz’ alez. Analysis of different approaches
for storing gml documents. In GIS ’02: Proceedings of the 10th
ACM international symposium on Advances in geographic information systems,
pages 11–16, 2002. [cited at p. 1]
[18] Jeff de La Beaujardiere. Opengis web map server interface implementation
specification revision 1.0.0, 2006. [cited at p. 14]
[19] O’Neil Delpratt, Rajeev Raman, and Naila Rahman. Engineering succinct
dom. In EDBT ’08: Proceedings of the 11th international conference on
Extending database technology, pages 49–60, 2008. [cited at p. 81]
[20] Panagiotis A. Vretanos (Eds.). Web feature service implementation specification
(version: 1.1.0), 2005. [cited at p. 11]
[21] Peter Schut (Eds.). Opengis R° web processing service (version: 1.0.0),
2007. [cited at p. 2]
[22] Mehdi Essid, Omar Boucelma, Franc﹐ois-Marie Colonna, and Yassine Lassoued.
Query processing in a geographic mediation system. In GIS ’04: Proceedings of the 12th annual ACM international workshop on Geographic
information systems, pages 101–108, 2004. [cited at p. 3]
[23] Jon Ferraiolo, Fujisawa Jun, and Dean Jackson. Scalable vector
graphics (svg) 1.1 specification, w3c recommendation 14 january
2003. Technical report, World Wide Web Consortium (W3C), 2003.
http://www.w3.org/TR/SVG11/. [cited at p. 11, 14]
[24] Thorsten Fiebig, Sven Helmer, Carl-Christian Kanne, Julia Mildenberger,
Guido Moerkotte, Robert Schiele, and Till Westmann. Anatomy of a native
xml base management system. The VLDB Journal, 11(4):292–314, 2002.
[cited at p. 82]
[25] Roy Goldman and Jennifer Widom. Dataguides: Enabling query formulation
and optimization in semistructured databases. In VLDB ’97: Proceedings of
the 23rd International Conference on Very Large Data Bases, pages 436–
445, 1997. [cited at p. 31, 39]
[26] Georg Gottlob, Christoph Koch, and Reinhard Pichler. Efficient algorithms
for processing xpath queries. ACM Trans. Database Syst., 30(2):444–491,
2005. [cited at p. 28]
[27] Georg Gottlob, Christoph Koch, and Reinhard Pichler. Efficient algorithms
for processing xpath queries. ACM Trans. Database Syst., 30(2):444–491,
2005. [cited at p. 56, 82]
[28] Paul Grosso and Daniel Veillard. Xml fragment interchange, w3c candidate
recommendation 12 february 2001. Technical report, W3C - World Wide
Web Consortium, 2001. [cited at p. 35, 82]
[29] Torsten Grust, Maurice Van Keulen, and Jens Teubner. Accelerating xpath
evaluation in any rdbms. ACM Trans. Database Syst., 29(1):91–131, 2004.
[cited at p. 31, 37, 39, 53]
[30] Antonin Guttman. R-trees: a dynamic index structure for spatial searching.
In SIGMOD ’84: Proceedings of the 1984 ACM SIGMOD international
conference on Management of data, pages 47–57, 1984. [cited at p. 19]
[31] Linda L. Hill. Georeferencing in digital libraries. D-Lib Magazine.
10(5), http: // www. dlib. org/ dlib/ may04/ hill/ 05hill. html , 2004.
[cited at p. 2, 77]
[32] Arnaud Le Hors, Philippe Le Hegaret, Lauren Wood, Gavin Nicol, Jonathan
Robie, Mike Champion, and Steve Byrne. Document object model (dom)
level 3 core specification version 1.0, w3c recommendation 07 april 2004.
Technical report, W3C, April 2007. [cited at p. 3]
[33] Chia-Hsin Huang, Tyng-Ruey Chuang, Dong-Po Deng, and Hahn-Ming
Lee. Efficient gml-native processors for web-based gis: techniques and
tools. In GIS ’06: Proceedings of the 14th annual ACM international symposium
on Advances in geographic information systems, pages 91–98, 2006.
[cited at p. 4, 63]
[34] Chia-Hsin Huang, Tyng-Ruey Chuang, and Hahn-Ming Lee. Fast structural
query with application to chinese treebank sentence retrieval. In DocEng
’04: Proceedings of the 2004 ACM symposium on Document engineering,
pages 11–20, 2004. [cited at p. 75, 81]
[35] Chia-Hsin Huang, Tyng-Ruey Chuang, and Hahn-Ming Lee. Prefiltering
techniques for efficient xml document processing. In DocEng ’05: Proceedings
of the 2005 ACM symposium on Document engineering, pages
149–158, 2005. [cited at p. 4, 18, 31, 32, 37, 54]
[36] Chia-Hsin Huang, Tyng-Ruey Chuang, James J. Lu, and Hahn-Ming Lee.
Xml evolution: a two-phase xml processing model using xml prefiltering
techniques. In VLDB ’06: Proceedings of the 32nd international conference
on Very large data bases, pages 1215–1218. VLDB Endowment, 2006.
[cited at p. 17, 18]
[37] Vanja Josifovski, Marcus Fontoura, and Attila Barta. Querying xml streams.
The VLDB Journal, 14(2):197–210, 2005. [cited at p. 27, 82]
[38] Seung Min Kim, Suk I. Yoo, Eunji Hong, Tae Gwon Kim, and Il Kon Kim.
A document object modeling method to retrieve data from a very large xml document. In DocEng ’07: Proceedings of the 2007 ACM symposium on
Document engineering, pages 59–68, 2007. [cited at p. 3, 82]
[39] Quanzhong Li and Bongki Moon. Indexing and querying xml data for regular
path expressions. In VLDB ’01: Proceedings of the 27th International
Conference on Very Large Data Bases, pages 361–370, 2001. [cited at p. 79]
[40] Lipyeow Lim, Min Wang, Sriram Padmanabhan, Jeffrey Scott Vitter, and
Ronald Parr. Xpathlearner: an on-line self-tuning markov histogram for
xml path selectivity estimation. In VLDB ’02: Proceedings of the 28th international
conference on Very Large Data Bases, pages 442–453, 2002.
[cited at p. 40]
[41] Lipyeow Lim, Min Wang, and Jeffrey Scott Vitter. Cxhist: an on-line
classification-based histogram for xml string selectivity estimation. In VLDB
’05: Proceedings of the 31st international conference on Very large data
bases, pages 1187–1198, 2005. [cited at p. 40]
[42] Chang-Tien Lu, Jr Raimundo F. Santos, Lakshmi N. Sripada, and Yufeng
Kou. Advances in gml for geospatial applications. Geoinformatica,
11(1):131–157, 2007. [cited at p. 1]
[43] Ali Mansouriana, Abbas Rajabifard, Mohammad Javad Valadan Zoej, and
Ian Williamson. Using sdi and web-based system to facilitate disaster
management. Computers & Geosciences, 32(3):303–315, March 2006.
[cited at p. 1]
[44] Am’ elie Marian and J’erˆome Sim’eon. Projecting xml documents. In VLDB
’2003: Proceedings of the 29th international conference on Very large data
bases, pages 213–224, 2003. [cited at p. 70, 81]
[45] Kavourasand Marinos, Koklaand Margarita, and Tomaiand Eleni. Comparing
categories among geographic ontologies. Computers & Geosciences,
31(2):145–154, March 2005. [cited at p. 77]
[46] Markus L. Noga, Steffen Schott, and Welf L‥owe. Lazy xml processing.
In DocEng ’02: Proceedings of the 2002 ACM symposium on Document
engineering, pages 88–94, 2002. [cited at p. 69, 81]
[47] Stelios Paparizos, Jignesh M. Patel, and H. V. Jagadish. Sigopt: Using
schema to optimize xml query processing. In ICDE, pages 1456–1460,
2007. [cited at p. 83]
[48] Feng Peng and Sudarshan S. Chawathe. Xsq: A streaming xpath engine.
ACM Trans. Database Syst., 30(2):577–623, 2005. [cited at p. 27, 82]
[49] Neoklis Polyzotis, Minos Garofalakis, and Yannis Ioannidis. Approximate
xml query answers. In SIGMOD ’04: Proceedings of the 2004 ACM SIGMOD
international conference on Management of data, pages 263–274,
2004. [cited at p. 51, 54]
[50] Clemens Portele. Opengis R° geography markup language (gml) encoding
standard, 2007. [cited at p. 2, 3, 7, 32]
[51] Robert G. RASKIN and Michael J. PAN. Knowledge representation in the
semantic web for earth and environmental terminology (sweet). Computers
& Geosciences, 31(9):1119–1125, 2005. [cited at p. 2, 76, 77]
[52] Flavio Rizzolo and Alberto Mendelzon. Indexing xml data with toxin. In
Proceedings of WebDB 2001, pages 49–54, 2001. [cited at p. 31, 39, 53]
[53] Albrecht Schmidt, Florian Waas, Martin Kersten, Michael J. Carey, Ioana
Manolescu, and Ralph Busse. Xmark: a benchmark for xml data management.
In VLDB ’02: Proceedings of the 28th international conference on
Very Large Data Bases, pages 974–985, 2002. [cited at p. 59, 70]
[54] Shashi Shekhar, Ranga Raju Vatsavai, Namita Sahay, Thomas E. Burk,
and Stephen Lime. Wms and gml based interoperable web mapping system.
In GIS ’01: Proceedings of the 9th ACM international symposium
on Advances in geographic information systems, pages 106–111, 2001.
[cited at p. 2]
[55] Fangju Wang, Jing Li, and Hooman Homayounfar. A space efficient xml
dom parser. Data Knowl. Eng., 60(1):185–207, 2007. [cited at p. 81]
[56] Guoren Wang, Mengchi Liu, Jeffrey Xu Yu, Bing Sun, Ge Yu, Jianhua Lv,
and Hongjun Lu. Effective schema-based xml query optimization techniques.
In IDEAS, pages 230–235, 2003. [cited at p. 83]
[57] Masatoshi Yoshikawa, Toshiyuki Amagasa, Takeyuki Shimura, and Shunsuke
Uemura. Xrel: a path-based approach to storage and retrieval of
xml documents using relational databases. ACM Trans. Interet Technol.,
1(1):110–141, 2001. [cited at p. 31, 39, 81]
[58] Ning Zhang, Peter J. Haas, Vanja Josifovski, Guy M. Lohman, and Chun
Zhang. Statistical learning techniques for costing xml queries. In VLDB ’05:
Proceedings of the 31st international conference on Very large data bases,
pages 289–300, 2005. [cited at p. 59]
[59] Fubao Zhu, Jihong Guan, and Shuigeng Zhou. Constraints-preserving gml
storage in object-relational databases. In GIS ’07: Proceedings of the 15th
annual ACM international symposium on Advances in geographic information
systems, pages 1–4, 2007. [cited at p. 2]
[60] Qinghua Zou, Shaorong Liu, and Wesley W. Chu. Ctree: a compact tree
for indexing xml data. In WIDM ’04: Proceedings of the 6th annual ACM
international workshop on Web information and data management, pages
39–46, 2004. [cited at p. 79]