A Prototype Implementation of a Framework for Organising Virtual Exhibitions over the Web

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A Prototype Implementation of a Framework for
Organising Virtual Exhibitions over the Web

• Ali Elbekai, Nick Rossiter
• School of Computing, Engineering and information
  sciences
• Northumbria University
• Email ali.elbekai_at_unn.ac.uk , nick.rossiter_at_unn.a
  c.uk

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Overview

• Related Work
• Prototype of Museum System
• Architecture of System
• Implementation of System

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Related Work 1

• Vassil Vassilev 1999
• general description/technical specification of
  information system for museum information
  processing
• Vassil Vassilev 2000
• publishing museum content over the Web, in
  archaeology, in watermark images and in
  industrial heritage
• Nicholas Crofts 2003
• practical application of the CIDOC CRM in
  integrating a large and diverse set of data
  sources.
• contain information relating to Geneva's
  architectural and cultural heritage.

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Related Work 2

• CIDOC/CIDOC CRM Special Interest Group
• 1994-2000 and 2000-2002
• define the underlying semantics of database
  schemata and document structures
• for museum documentation
• support of good practice in
• conceptual modelling
• data transformation and data exchange
• information integration and mediation of
  heterogeneous sources.

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Related Work 3

• Bourret 2004
• XML (and its relations) have many facilities in
  common with real databases such as
• storage (XML documents), schemas (DTDs, XML
  schema languages) and programming interfaces
  (SAX, DOM, and JDOM)
• Wiederhold 1995
• wrapper mediator architecture
• uniform user interface
• query integrated views of heterogeneous sources
• Manolescu et al 2001
• query processor for different schema generation
  techniques
• materialized views over a virtual global schema

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Related Work 4

• Elbekai Rossiter 2005a
• algorithm as a technological solution for XQuery
  interpreter generating
• XSL stylesheet for transforming XML query to SQL
  query
• XSL stylesheet in implementation of a framework
  for organising virtual exhibitions
• Elbekai Rossiter 2005b
• prototype of a framework for organising virtual
  exhibitions
• single XML Schema for specification of the common
  exhibition
• utilising contemporary information technologies
  for processing XML data over the Web
• pan-European collaboration for organisation of
  virtual exhibitions information

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Prototype

• Assumes content published is extract of
  CIDOC-compliant museum database
• easy standardisation and further dissemination
• Prototype system presented
• is built entirely using public domain stack of
  technologies for processing XML data in Java
• J2SE, J2EE and additional XML and Web Services
  packages
• functions as an entirely server-side Web
  application executed by Tomcat server connected
  to a backend database (one for each participating
  museum)

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Entity Relationship Diagrams

• From Chen 1976, provide logical structure of the
  databases for our proposed system
• Structure features
• Collection may relate to a number of Objects.
• Object may contain much Information such as
  Location, Reference, Image, Documentation,
  Acquisition and Collection.
• Exhibition has many Collections
• Exhibitions can be of different kinds
• public display, virtual exhibition or archive
  (type of exhibition)
• Institution has many Visitor groups, Exhibitions,
  Collections, Objects, Information and one Address

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Figure 1 Entity Relationship Diagram for the
Museum System
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Algorithm for Generating XML Stylesheet

• Use generated XSL stylesheet for transforming
  XQueries to SQL queries
• For each XML schema/stylesheet
• build Document Object Model (DOM) tree
• pull nodes from DOM
• add SELECT clauses
• Generate new generic XML Stylesheet with SQL code

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Figure 2 An algorithm for generating XSL to
transform XQueries to SQL queries.
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Figure 3 Generic XSL Stylesheet
(XQuerytoSQLTrans.xsl) for transforming XQuery
to SQL
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Architecture

• Web browser (Client)
• that can connect to the server
• to access the Java servlets
• the client can use PCs to run a Java servlet
• Middle Server
• DBMS server
• with SQL tables to provide database storage

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Middle Server in more detail

• Middle server
• set of servers and internal network connecting
  them
• provides web server capable of accessing data
  from DBMS and making it available to the client.
• choices include
• Web server, Web sever with servlets (Tomcat),
  SOAP container (AXIS), a Virtual exhibition
  servlet, Java Server Pages, HTML Pages and XSL
  stylesheets
• The communication protocol between the database
  and the museum server could be JDBC

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Figure 4 Architecture for the museum system
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Implementation 1

• Integrated approach
• Step 1
• formulate an XQuery
• send query to web server tomcat with HTTP
• Step 2
• XSL Libraries transform XQuery to SQL
• Step 3
• SQL query string is generated
• Java servlet connects to database
• passes the SQL query string to database server
  over JDBC

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Implementation 2

• Step 4
• Java servlet class retrieves information
  according to SQL query string
• XSL stylesheet transforms retrieved data to XML
• sends output back to the client
• Result is shown on Tomcat server

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Example for search and display of information 1

• After successful login
• client is able to search and display object
  information.
• Step 1
• Client specifies and sends an XQuery such as
• For obj in ltcollectiongt Return ltobjgt Where
  obj/ltregis_Dategt gt 10.01.02
• to the Web server as a URL by using HTTP

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Example for search and display of information 2

• Step 2
• Museum server parses and transforms request by
  XSL stylesheet (XQuerytoSQLTran.xsl) on the
  server and creates a SQL query string
• Step 3
• transformation is done
• SQL query string generated
• Java servlet is connected to database server
• SQL query passed to the database server over JDBC

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Example for search and display of information 3

• Step 4
• query is executed
• database server returns report to museum server
• XSL stylesheet transforms report to HTML by using
  the XSL stylesheet (GenXSLHTML.xsl)
• sends output back to the client.
• Result is shown on Tomcat server

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Figure 5 Institutional information displayed
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Figure 6 Institutional Information displayed on
Tomcat server
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Figure 7 Search and display objects
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Figure 8 Objects displayed by the Client on
Tomcat Server
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Figure 9 Search and display information
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Figure 10 Objects with registration date is
10.01.03 on Tomcat Server
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Figure 11 Search and display information
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Figure 12 Opening exhibition information on
Tomcat Server
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Contribution 1

• Prototype implementation of a framework for
  organising virtual exhibitions
• Uses information provided by the collaborating
  museums in the form of Web services.
• The museum content published by the museums is
• organised in a homogeneous virtual exhibition
  space by an exhibition curator
• accessible from a single point of entry - the
  Virtual Exhibition site.

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Contribution 2

• The prototype
• assumes content published is an extract of a
  CIDOC-compliant museum database,
• allowing easy standardisation and further
  dissemination.
• built entirely using public domain stack of
  technologies
• for processing XML data in Java (J2SE, J2EE and
  additional XML and Web Services packages).
• functions as an entirely server-side Web
  application
• executed by Tomcat server connected to a backend
  database.