階層式詮釋資料架構應用於地理資料之描述與流通之研究

Hierarchical Metadata Framework towards the Description and Application of Geographin Information

在善用近年快速發展之開放式地理資訊系統技術後，空間資料之流通已不再侷限於現存之單一檔案內容，而可依循使用者之需求，即時供應符合約制條件之資料。如何伴隨流通之資料而建立適切之詮釋資料內容因此成為必要之考量，但如何在低成本、低工作量之前提下完成此工作仍是目前有待克服的瓶頸。階層式觀點之引入可有效減低重複之資料建置量，並因應需求而提供合適之描述內容。本文探討階層式詮釋資料之發展架構，並依建置型態而分析不同層級詮釋資料項目內容間複製、補充、聚合及覆寫等操作之適用情形，以達到降低供應者端項目填寫數量及動態產生符合使用者所需詮釋資料之目標。基礎於本研究之規劃機制，未來詮釋資料之生產及流通將可以資料庫、檔案或物件為對象而描述與剖析，更適合於未來以圖徵為基礎之開放式地理資料流通環境。 By taking advantages of recent development of GIS technology, the distribution ofgeographic information is no longer restricted to be based on individual files that already exist.Since users nowadays can already retrieve only those data content qualifying their constraints, thesupply of metadata that appropriately describe the distributed data content therefore becomes anecessary consideration. How to complete this task with low cost and working load isnonetheless still a technological bottleneck that needs to be overcome. To reduce providers’duplicated metadata entry loading and dynamically generate metadata that meet users’ applicationneeds, this paper investigates the developed framework of hierarchical metadata and propose fourmajor operations, namely, copy, supplement, aggregation and overwritten, which exist betweenthe different levels of hierarchical metadata elements. Based on the proposed mechanism, theproduction and distribution of metadata can be respectively created on the basis of database, fileor object. This progress provides an advantage of serving a better foundation for the futurefeature-based OpenGIS data distribution environment.

By taking advantages of recent development of GIS technology, the distribution ofgeographic information is no longer restricted to be based on individual files that already exist.Since users nowadays can already retrieve only those data content qualifying their constraints, thesupply of metadata that appropriately describe the distributed data content therefore becomes anecessary consideration. How to complete this task with low cost and working load isnonetheless still a technological bottleneck that needs to be overcome. To reduce providers’duplicated metadata entry loading and dynamically generate metadata that meet users’ applicationneeds, this paper investigates the developed framework of hierarchical metadata and propose fourmajor operations, namely, copy, supplement, aggregation and overwritten, which exist betweenthe different levels of hierarchical metadata elements. Based on the proposed mechanism, theproduction and distribution of metadata can be respectively created on the basis of database, fileor object. This progress provides an advantage of serving a better foundation for the futurefeature-based OpenGIS data distribution environment.