Metadata Standard Crosswalks

劉仁翔林黃瑋王憲章報告人 : 劉仁翔 97/10/4

Tables

What is Metadata Crosswalks? Different Metadata format Examples of Crosswalks Challenges for Crosswalks Findings & Results References

What is Metadata Crosswalks?

A semantic mapping of metadata elements across metadata schema specifications. Crosswalks permit searching across multiple databases that use different schema. From: Encyclopedia of Library and Information

Science, Miriam A. Drake,P1881.

A crosswalk is a table or chart that shows the relationships and equivalencies (and highlights the inevitable gaps) between two or more metadata formats From: Introduction to Metadata, Mary S. Woodley,

Demand of Interoperability

異質通透性

分散通透性

減少投資成本運算元通透性

系統擴充性

Interoperability

Crosswalk Means:

為因應 Metadata Interoperability 互通性 ，設計一套對照表，使兩個不同 Metadata系統所含項目可對照 (Mapping) ，維持一致的品質 如： USMARC 與 Dublin Core 的對照表，

EAD 與 USMARC 的對照表等。 透過 Crosswalk 對照，可在資料庫檢索

搜尋到不同的異質資料 ( 如 : 圖書、藏品、光碟、影音等 )

Different Metadata format

● 圖書館社群：MARC, MODS● 博物館社群： CDWA, VRA, CIDOC● 檔案館社群： EAD● 政府社群： GILS● 視覺資源社群： VRA Core Categories● 植物標本館社群： HISPID, DarwinCore● 教育社群： IEEE LOM● 音樂社群： SMDL

Crosswalks

理想的對照應指出三個內涵

Crosswalk

元素Element

語意Semantic

語法Syntax

http://www.getty.edu/research/conducting_research/standards/intrometadata/crosswalks.html

http://www.loc.gov/marc/marc2dc.html

Challenges for Crosswalks(1)

No two metadata schemes are 100% equivalent 沒有兩種詮釋資料可完全搭配

“lateral” (one-way) mappings from one scheme to another 具單項性的對照特性 scheme A to scheme B and from scheme B to sch

eme A. ( 見下張 )

lateral (one-way) mappings

MARC fieldDublin Core

element

210 Abbreviated Title

→ Title

222 Key Title → Title

240 Uniform Title

→ Title

242 Translated Title

→ Title

245 Title Statement

→ Title

246 Variant Title

→ Title

Dublin Core element

MARC field

Title →245 Title

Statement

Title →245 Title

Statement

Title →245 Title

Statement

Title →245 Title

Statement

Title →245 Title

Statement

Title →245 Title

Statement

Challenges for Crosswalks(2)

Problems one-to-many mapping 一對多的特性 One scheme may allow an element to be repeate

d more than once while another only allows that element to appear once with multiple terms in it

schema A 允許一個元素可以重複，但 schemaB元素僅能出現一次 例 :DC Creator 可重複出現，MARC 主要作者欄僅能出現一次

Challenges for Crosswalks(3)

Schemes may have different data formats (eg: John Doe or Doe, John)不同的著錄格式

An element in one scheme may be indexed but the equivalent element in the other scheme is not 選取被索引的元素不同

Use different controlled vocabularies 使用不同的控制詞彙

Schemes may change their standards over time標準的修訂

How to Solve?

Need to Compromise 需要妥協與制定標準 Here are some standards ( 資料來源 :wikipedia)

MARC to Dublin Core (Library of Congress) http://loc.gov/marc/marc2dc.html

Dublin Core to MARC21 (Library of Congress) http://www.loc.gov/marc/dccross.html

Dublin Core to EAD (Getty) http://www.getty.edu/research/conducting_research/standards/intrometadata/dc_ead.html

Mapping Between Metadata formats (UKOLN) http://www.ukoln.ac.uk/metadata/interoperability/

ONIX to MARC21 (Library of Congress ) http://www.loc.gov/marc/onix2marc.html

TEI header to USMARC http://etext.lib.virginia.edu/tei/tei-marc.html/

中央研究院後設資料工作組 ( 數位典藏國家型科技計畫 )http://metadata.teldap.tw/standard/standard-frame.html

http://metadata.teldap.tw/project/work-status/NPMqi/npmqi-elements_v1-2.pdf

http://metadata.teldap.tw/project/work-status/neige/elements.html

Findings & Results(1)

In order to have a useful and good Interoperability Union System (Catalog), We may use Metadata Crosswalks Standard Table to map different types of Metadata schema

Use Crosswalks to maintain “element’s consistency”, and “authority”

Crosswalk Table would not be seen on system,but it’s like a game rule if you want to join

Findings & Results(2)

DC 是公認最適合應用在跨知識領域描述格式的對映工作 簡單（ Simple ）：只有 15 個欄位，廣度夠 有修飾詞（ Qualifier ）：因為欄位會經修正和編碼。 易用與易懂的特性 簡單的 DC 紀錄是可以做為建立複雜的詮釋資料之

基礎。 Dublin Core Metadata Initiative (DCMI) 機構維護

References

Woodley, Mary. (2000). Crosswalks the Path to Universal Access?. In: Baca, M. et al. (2000) Introduction to Metadata: Pathway to Digital Information.http://www.getty.edu/research/conducting_research/standards/intrometadata/path.html

Lois Mai Chan and Marcia Lei Zeng. (2006). Metadata Interoperability and Standardization – A Study of Methodology http://www.dlib.org/dlib/june06/chan/06chan.html

Taylor, Arlene. 2004. The organization of information. 2nd ed., Westport, Conn.: Libraries Unlimited. P.154 

中央研究院後設資料工作組 ( 數位典藏國家型科技計畫 )http://metadata.teldap.tw/standard/standard-frame.html

何佳欣、從異質系統的資訊組織模式探討數位圖書館整合檢索之效能—以華文知識入口網為例、中華民國圖書館學會會報 75 卷 ( 民 94) 、頁 75-93

柯皓仁、詮釋資料與數位圖書館互通性之探討。大學圖書館 5 卷 1 期 ( 民 90) 、頁 49-78

數位典藏國家型科技計畫技術彙編、 3-5 從典藏資料交換角度探討後設資料之設計與標準化問題 http://www.ndap.org.tw/2_techreport/index.php?pid=41

張慧銖、數位環境中機讀編目格式的新面貌—MODS 的產生與發展。國家圖書館館刊 95 卷2 期 ( 民 95) 頁 1-24

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