1. Presented by: Jacky Ma Date: 11 Dec 2001
A Multi-Model XML (MMX) Framework for Digital Video Library (DVL) Systems
Presented by: Jacky Ma
Date: 11 Dec 2001

2. Presentation Outline Introduction The MMX Framework Conclusion
Background
An Example
The Problem
The MMX Framework
Models
Syntax
Behaviors
Conclusion
Contribution
Difficulties

3. Introduction

4. Background Previous Research Motivation Digital Video Library (DVL)
Extensible Markup Language (XML)
Motivation
Facilitate searching in DVL with XML
Search XML in specialized and customizable way

5. An XML Example <key N="7" S="3" E="16" W="1"/>
<node id="1">
<key N="7" S="3" E="6" W="1"/>
<key N="7" S="5" E="2" W="1"/>
<data x="1" y="5">itemA</data>
<data x="2" y="7">itemB</data>
</node>
<node id="2">
<key N="4" S="3" E="6" W="4"/>
<data x="4" y="3">itemA</data>
<data x="6" y="4">itemC</data>
<key N="6" S="4" E="16" W="8"/>
<key N="5" S="4" E="8" W="9"/>
<data x="8" y="4">itemG</data>
<data x="9" y="5">itemD</data>
<key N="6" S="5" E="11" W="16"/>
<data x="11" y="5">itemF</data>
<data x="16" y="6">itemE</data>

6. Queried by XPath Based on the XML structure and the data
Retrieve the node “data” containing attribute “x=8”
Can also retrieve the parent-node, sibling-node, etc.
/node[1]/node[1]/key/following-sibling::*
Useful in XSLT

7. Queried by RDBMS Based on the data Classical “select * from” clause
Can retrieve any item based on its attributes
id1 N1 S1 E1 W1
id0 N0 S0 E0 W0 x y
data 1 7 3 6 5 2
itemA
itemB 4
itemC 16 8 9
itemD
itemG 11
itemE

8. Queried by R-Tree How about if I told you it is a R-Tree?
Spatial Queries
Give me the point at (2,7)
Give me the point nearest to (4,4)
Nearest Neighbor Search
Give me the point nearest to “itemB”

9. What makes the difference?
Make use of knowledge we have on the data given.
We can do the spatial query ONLY if we know the data segment is representing a R-Tree, and understand what are the attributes (id, N, S, E, W, etc.) representing.

10. Problem
There are a lot of different data structures, different data manipulations, and different query methods.
How could we model them with XML?

11. The MMX Framework

12. The MMX Framework To solve the previous problem:
A framework allowing various data structures to be implemented upon
Knowledge on knowledge
Describe the structural information of XML Document
Empirical knowledge
Analogeous to RDF
Manipulation of information with structural information
Queries
Updates
Exchanging information

13. Model the “Models” The kinds of “Models” is unlimited
They may looks “similar”, all of them can be represented by graphs or XML tree
But the underlying structures, constraints and algorithms are different
No generic descriptive syntax
Use a “label” and “procedural” approach
Label “known” structures, and
Program the “new” structures

14. Major “Labeled Models”
Generic
Object
Vector
Relational
Document
Tree

15. Basic Model Abstract Data Object (ADO)
Encapsulate the information about a package of structured data
Accessible at Root
Pointing out at Child Node
Includes:
Model Name
Properties
Behaviors
Data

16. Syntax Serialization Syntax Schema Syntax Embedded in XML Document
Defines elements like <ado>, <property>, etc.
Easy to use
Change the document instance
Schema Syntax
Embedded in XML Document Schema
Associate element names with structural information
More complicated
Do not need to change the document
Favors reusability, scalability and interoperability

17. Behaviors Behaviors Properties Data The program to manipulate the data
“Default” Behaviors allow operations on any standard ADOs
Properties
Persistent variables
Keeping the state of the ADO
Data
User data
Appear as DOM Tree to the Behavior program

18. Conclusion

19. Contribution Propose a representation to encapsulate data structures
A procedural model to manipulate the data
Promote the use of interoperable data structure format
Describe how will typical “Models” functions
Describe the “Tree” model which features spatial queries, and particularly suitable for searching in DVL

20. Difficulties
No general syntax can precisely describe all kinds of data structures
Not possible to include all data structures one-by-one

21. Research Direction
Develop the full specification for the MMX Framework
Develop various structures that tailored for content-based searching in DVL

22. Q&A