Transcript A Multi-Model XML (MMX) Framework for Digital Video Library (DVL) Systems

A Multi-Model XML (MMX) Framework
for
Digital Video Library (DVL) Systems
Presented by: Jacky Ma
Date: 11 Dec 2001
Presentation Outline
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Introduction
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The MMX Framework
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Background
An Example
The Problem
Models
Syntax
Behaviors
Conclusion
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Contribution
Difficulties
Introduction
Background
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Previous Research
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Digital Video Library (DVL)
Extensible Markup Language (XML)
Motivation
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Facilitate searching in DVL with XML
Search XML in specialized and customizable
way
An XML Example
<key N="7" S="3" E="16" W="1"/>
<node id="1">
<key N="7" S="3" E="6" W="1"/>
<node id="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>
</node>
</node>
<node id="2">
<key N="6" S="4" E="16" W="8"/>
<node id="1">
<key N="5" S="4" E="8" W="9"/>
<data x="8" y="4">itemG</data>
<data x="9" y="5">itemD</data>
</node>
<node id="2">
<key N="6" S="5" E="11" W="16"/>
<data x="11" y="5">itemF</data>
<data x="16" y="6">itemE</data>
</node>
</node>
Document
Element "Key"
Element "Node"
Element "Data"
Queried by XPath
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Based on the XML structure and the data
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Retrieve the node “data” containing attribute
“x=8”
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Can also retrieve the parent-node, siblingnode, etc.
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//data[@x=‘8’]
/node[1]/node[1]/key/following-sibling::*
Useful in XSLT
Queried by RDBMS
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Based on the data
Classical “select * from” clause
Can retrieve any item based on its
attributes
i
d
1
N
1
S
1
E
1
i
W
d
1
0
N
0
S
0
E
0
W
0
x
y
data
1
7
3
6
1
1
7
5
2
1
1
5
itemA
1
7
3
6
1
1
7
5
2
1
2
7
itemB
1
7
3
6
1
2
4
3
6
4
4
3
itemA
1
7
3
6
1
2
4
3
6
4
6
4
itemC
2
6
4
16
8
1
5
4
8
9
9
5
itemD
2
6
4
16
8
1
5
4
8
9
8
4
itemG
2
6
4
16
8
2
6
5
11
16
11
5
itemE
2
6
4
16
8
2
6
5
11
16
16
6
itemE
Queried by R-Tree
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How about if I told you it is a R-Tree?
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Spatial Queries
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Give me the point at (2,7)
Give me the point nearest to (4,4)
Nearest Neighbor Search
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Give me the point nearest to “itemB”
(0,0)
What makes the difference?
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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 RTree, and understand what are the attributes
(id, N, S, E, W, etc.) representing.
Problem
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There are a lot of different data structures,
different data manipulations, and different
query methods.
How could we model them with XML?
The MMX Framework
The MMX Framework
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To solve the previous problem:
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Knowledge on knowledge
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A framework allowing various data structures to be
implemented upon
Describe the structural information of XML Document
Empirical knowledge
Analogeous to RDF
Manipulation of information with structural information
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Queries
Updates
Exchanging information
Model the “Models”
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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
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Label “known” structures, and
Program the “new” structures
Major “Labeled Models”
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Generic
Object
Vector
Relational
Document
Tree
Basic Model
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Abstract Data Object (ADO)
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Encapsulate the information about a package
of structured data
Accessible at Root
Pointing out at Child Node
Includes:
Parent Node
Model Name
 Properties
 Behaviors
 Data
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In References
Child
Node
Head Node
Abstract Data Object:
Properties,
Behaviours,
Data
Out References
Leave Nodes
Out References
Child
Node
Child
Node
Syntax
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Serialization Syntax
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Embedded in XML Document
Defines elements like <ado>, <property>, etc.
Easy to use
Change the document instance
Schema Syntax
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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
Behaviors
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Behaviors
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Properties
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The program to manipulate the data
“Default” Behaviors allow operations on any
standard ADOs
Persistent variables
Keeping the state of the ADO
Data
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User data
Appear as DOM Tree to the Behavior program
Conclusion
Contribution
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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
Difficulties
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No general syntax can precisely describe
all kinds of data structures
Not possible to include all data structures
one-by-one
Research Direction
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Develop the full specification for the MMX
Framework
Develop various structures that tailored for
content-based searching in DVL
Q&A