Union Catalogs System: Features

1. Single-window explore-and-search engine
   The Union Catalogs System's single window lets one access both the explore-and-search engine and the primary information databases of every large archiving organization in the nation, which contain richer, more in-depth resources. One can also search the digital holdings by academic field, geographical location, or time period.
2. A collective system.
   The Digital Archives Union Catalogs System uses the Open Archives Initiative Protocol for Metadata Harvesting (OAI-PMH) technology and an Extensible Markup Language (XML) structure. The technological theory is that the server will periodically gather, or be provided with, metadata about holdings from each information database, thus establishing a combined union catalog. The digital items are stored in each archiving unit, instead of at the server. The user will, according to the search results, be linked to the original archiving organization's system.

Union Catalogs System: Functions

1. Browse according to catalog classifications
   1. Content themeThe Union Catalogs System is divided into 11 themes according to the type and characteristics of the holdings. These include Biology, Geology, Anthropology, Archives, Artifacts, Calligraphy and Painting, Maps and Remote Images, Stone and Bronze Rubbings, Rare Books, Archaeology, and Journalism and Mass Media. This lets one browse according to discipline or within a particular discipline, in addition to viewing listings by a brief description or picture.
   2. Time periodThe Union Catalogs System allows users to search holdings by time period as well as browse according to a time-grid reference.
   3. GeographyIn addition to time period, the allows users to browse according to the holding's geographical attributes. Using Geographic Information System (GIS) technology, users can browse intuitively by selecting a geographic position on the map, or use map-layer views to show an item's largest distribution area.
   4. Archiving organizations and projectsUsers can also browse the collection according to the holding's original archiving unit, in order to understand the item's origins and the characteristics of the archiving organization.
2. Search
   1. Entire text and Boolean searchIn addition to standard keyword searches of the entire text, the Union Catalogs System also supports Boolean style 'or', 'and' and 'not' searches that allow one to search more flexibly and accurately. A space between keywords produces a default 'or' search.
   2. Metadata step-wise searchIn order to combine resources from each academic field, the Union Catalogs System uses the Dublin Core (DC) element set and categorizes the metadata into the 15 main elemental structures:
   • Title: The name given to the resource.
   • Creator: The person/s or organization/s primarily responsible for the intellectual content of the resource (the author).
   • Subject & Keywords: The topic of the resource.
   • Description: A textual explanation of the content of the resource.
   • Publisher: The entity responsible for making the resource available in its present form.
   • Contributors: Person/s or organization/s who have made intellectual contributions to the resource.
   • Date: The date the resource was made available in its present form.
   • Resource Type: The characteristics or the type of the resource.
   • Format: The data representation of the resource on either the physical or digital formation of the resource.
   • Resource Identifier: Unique identifiers of the resource.
   • Source: The work from which the current resource is derived.
   • Language: The language/s of the intellectual content of the resource.
   • Relation: The relationship to other resources.
   • Coverage:The spatial locations and temporal duration characteristics of the resource.
   • Rights Management: Information describing relevant rights relating to the resource.
     

   These 15 core elements allow the Union Catalogs System to combine resources from different fields and allow unrestrictive use of these elements to conduct combined, more precise information searches.

Union Catalogs System: Future Development

1. Condition-matching combined searchesIn addition to browse and search functions, the Union Catalogs System plans to provide combined text, time period, and geographical location conditional searches so users can find the needed information more precisely.
2. Progressively narrowing precision searchesAs the Union Catalogs System's content becomes larger and more complex, normal searches may sometimes yield too many results. The Union Catalogs System plans to provide a 'search within results' function to shorten the search time and increase precision.
3. Classification by reviewsThe Union Catalogs System plans to classify and organize according to the search terms keyed in by the user, or to provide relevant word searches within search results, to make the Union Catalogs System more useful and effective.
4. Mechanisms to strengthen digital property managementWithin the realm of reasonable use, issues of digital contents' rights licensing and user management need to be addressed. In addition, the cost of managing digital contents' rights can be reduced with the assistance of applicable technology.
5. Strengthen international cooperationThe Union Catalogs System plans to reach out through exchanges and joint projects with digital libraries and museums internationally. and to raise the international acceptance of Chinese-language information through metadata searches.