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Complex relationships for the semantic web

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Title: Complex relationships for the semantic web


1
Complex relationships for the semantic web
  • Amir Ali Khosravi
  • 82702903

2
  • The emphasis will shift from finding documents to
    finding facts, actionable information, and
    insights
  • Discover relevant and interesting relationships
    amongst the entities that these documents describe

3
Introduction
  • To take maximum advantage of awareness we need
    support meaningful information requests
  • Current ontological represetational schemes
    represent knowledge as a hierarchical taxonomy of
    concepts and relationships such as
    is-a/role-of,instance of/member-of and part of
  • Support limited complexity
  • InfoQuilt extend support for semantics by
    supporting computations involving lateral, user
    defined relationships
  • Relationships across domains, may not
    necessareily hierarchical in nature

4
Introduction
  • Does nuclear Testing cause Earthquakes?
  • Natural-Disasters.Earthquake, Nuclear-Weapons.Nucl
    ear-Testing
  • The meaning of cause could be based on the
    proximity in time and distance between two events

5
Classification of relationships
  • Content independent relationships two documents
    may be relatedd to each other by virtue of them
    being stored on the same server or file system,
    or relationship between a document and its date
    of modification

6
  • Content Dependent relationships either the
    information content they refer to or based on
    some representation of it thereof
  • Direct Content dependent relationships relation
    between two entities being mentioned in the same
    pragraph
  • Content descriptive relationships the fact that
    X is CEO of a company Y is computed based on the
    existence of an ontlogy (intra-domain
    relationships and inter-domain relationships

7
Content descriptive relationships
  • Direct Semantic relationships Intel
    is-a-competitior-of Motorola
  • Complex Transitive RelationshipsRemzi and Dick
    linked to the same teroorist organization
  • Inter-domain Multi-ontology Relationships

8
Representation of relationships
  • Arity
  • Cardinality
  • Direct vs. transitive relationships
  • Crisp vs. fuzzy
  • Properties vs. relations
  • Structural composition

9
  • Deficiency shared by most of these languages is
    the absence of a mechanism that can model complex
    operators
  • Earthquake causing tsunami Temporal and spatial
    proximity
  • InfoQuilts supports such operators by allowing
    the use of user defined functions as operators
  • The system particularly needs to extract
    domain-specific or contextually relevant metadata
    from all the data sources
  • Knowledge of the characteristics of the domains
    of interest gives us the ability to optimize the
    processing of information requests

10
  • A form of knowledge discovery HAND
  • Domain modeling uses ontologies, domain rules,
    functional dependency, support of user defined
    inter-ontological relationships
  • Rich and powerful querying mechanism IScape
  • User defined functions as complex operators
  • Ability to handle heterogeneous content
  • Information request processing utilizing domain
    and resource characteristics

11
Domain Modeling
  • InfoQuilt uses ontologies to model the domains

12
  • Attributes
  • Earthquake(latitude, longitude, region,
    eventDate, Description, damagePhoto,
    numberOfDeaths, magnitude)
  • Domain Rules
  • latitude gt -90 , latitude lt 90
  • Earthquake(latitude, longitude, region,
    eventDate, Description, damagePhoto,
    numberOfDeaths, magnitude,
  • latitude gt -90 , latitude lt 90
  • longitude gt -180, longitude lt 180)

13
  • Functional Dependencies(FD)
  • is used to retrieve information (attribute
    values) that is missing from a resource by using
    another resource
  • testSite -gt latitude longitude
  • Earthquake(latitude, longitude, region,
    eventDate, Description, damagePhoto,
    numberOfDeaths, magnitude,
  • latitude gt -90 , latitude lt 90
  • longitude gt -180, longitude lt 180,
  • testSite -gt latitude longitude )

14
Interontological relationships
  • We can say that some nuclear test could have
    caused an earthquake if we see that the
    earthquake occurred some time after the nuclear
    test was conducted and in nearby region
  • NuclearTest Causes Earthquake
  • lt dateDifference (NuclearTest.eventDate,
    Earthquake.eventDate) lt 30 AND distance(
    NuclearTest.latitude, NuclearTest.longitude,
    Earthquake.latitude, Earthquake.longitude) lt 10000

15
Operations
  • Find all earthquakes with epicenter in a 5000
    mile radius area of the location at latitude
    60.790 North and longitude 97.570 East
  • Another important advantage the system can
    support complex post-processing of data
  • To be able to dynamically and easily add new
    operations as well as update and delete existing
    ones, InfoQuilt maintains Function Store

16
Information Scapes (IScapes)
  • query generally explicitly specifies the exact
    sources, how data from these sources should be
    integrated, it does not understand what the user
    is asking
  • IScape, can understand what the user is inquiring
    by embedding semantic information

17
  • a computing paradigm that allows users to query
    and analyze the data available from a diverse
    autonomous sources, gain better understanding of
    the domains and their interactions as well as
    discover and study relationships
  • Find all earthquakes with epicenter in a 5000
    mile radius area of the location at latitude
    60.790 North and longitude 97.570 East and find
    all tsunamis that they might have caused

18
  • The preset constraint and runtime configurable
    constraint , similar to WHERE
  • IScape builder to construct and execute IScapes
    and analyze results

19
Human Assisted Knowledge Discovery(HAND)
  • Transitive relationships Earthquake causes
    Tsunami, Tsunami affects Enviornment,
    Earthquake affects Enviornment
  • IScape 1 When was the earliest recorded nuclear
    test conducted
  • IScape 2 Find the total number of earthquakes
    with a magnitude 5.8 or higher on the Richter
    scale per year starting from year 1990
  • IScape 3 Find the average number of earthquakes
    per year with a magnitude 5.8 or higher on the
    Richter scale for the period 1900-1949 and for
    the period 1950-present

20
  • IScape 4 For each group of earthquakes with
    magnitudes in the ranges 5.8-6, 6-7, 7-8, 8-9,
    and magnitudes higher than 9 on the richter scale
    starting from year 1900, find the number of
    earthquakes
  • IScape 5 Find nuclear tests conducted after
    january 1,1950 and find any earthquakes that
    occurred not later than a certain number of days
    after the test and such that its epicenter was
    located no farther than a certain distance from
    the test site

21
InfoQuil runtime architecture
  • Multi-agent information brokering architecture at
    runtime

22
Steps of precessing of an IScape
  • User agent sends IScape to the broker agent for
    processing
  • Broker agent sends the IScape to the planning
    agent
  • Planning agent creates an execution plan for the
    IScape
  • Planning agent returns the plan to the broker
    Agent
  • Broker agent sends the plan to the correlation
    agent for processing
  • Correlation agent starts executing the plan
  • Correlation agent returns the final result to the
    broker agent
  • Broker agent forwards the result to the user
    agent
  • Supports easy dynamic addition and removal of
    resources

23
Information Extraction and integration
  • Extract it as needed Vs. extract it offline and
    maintain it in a local database
  • Important metrics for Information extraction
    recall , precision
  • Information integration systems usually provide a
    uniform means of representing the information
    from multiple sources
  • It is done offline and for sources with
    relatively static data
  • METIS toolkit is used to create a single
    repository of information for a domain

24
METIS architecture
25
Resource Modeling
  • Resource Attributes
  • SignificantEarthquakesDB( eventDate, Description,
    region, magnitude, latitude, longitude,
    numberofDeaths, damagePhoto)
  • EarthquakesAfter1990( eventDate, region,
    magnitude, numberOfDeaths, damagePhoto )
  • Binding Patterns (BP)
  • A set of attributes that the system must be able
    to suply values for in order to query the
    resource
  • fromCity, fromState, toCity, toState,
    departureDate

26
  • Data Characteristic (DC) Rules
  • AirTranAirways (airlinecompany, flightNumber,
    fromCity, fromState, toState, DepartureDate,
    fare, departureTime, arrivalTime, dc
    airlineCompany AirTran Airways, fromCity,
    fromState, toCity, toState, departureDate )
  • Find all the flights operated by Delta Airlines
    from Boston, MA to Los Angeles, CA on February
    19,2001

27
  • Local Completeness (LC) Rules
  • All the information for the subset
  • AirTranAirways (airlinecompany, flightNumber,
    fromCity, fromState, toState, DepartureDate,
    fare, departureTime, arrivalTime, dc
    airlineCompany AirTran Airways, lc
    airlineCompany AirTran Airways)

28
Planning and optimization
  • Two ontologies NuclearTest, Earthquake
  • Specifications of the information sources
  • NuclearTestsDB( testSite, explosiveYield,
    bodyWaveMagnitude, testType, eventDate,
    conductedBy, dcbodyWaveMagnitudegt 3, dc
    eventDate gt January 1, 1985 )
  • NuclearTestSites (testSite, latitude, longitude
    )
  • SignificantEarthquakeDB( eventDate, description,
    region, magnitude, latitude, longitude,
    numberOfDeaths, damagePhoto, dc eventDategt
    january 1, 1970 )

29
Planning and optimization
  • Planning agent uses the following rules to select
    the resources that are relevant
  • Locally complete Sources
  • Non Locally Complete Sources
  • Binding Patterns
  • Associate resource to supply values for missing
    attributes

30
  • NuclearTestsDB has two missing attributes
    latitude nad longitude, planner uses FD testSite
    -gt latitude longitude using NuclearTestSites as
    an associate resource, function testSiteEquals
    from the function store is used

31
IScape Execution and monitoring
  • User agent passes the IScape to the Broker agent.
  • The broker agent starts the processing of the
    IScape by coordinating other agents,
  • first asks planning agent to create an execution
    plan planning agent interacts with the knowledge
    agent to access information about domains, in
    IScape and resources
  • Creates an execution plan
  • Sends it back to the broker
  • Broker sends to correlation agent
  • Final result returned to broker and user agent

32
IScape processing monitor
  • Execution of the plan in the correlation agent is
    multi-threaded and parallel

33
Knowledge Builder (KB)
  • Create specifications of domains, inter-domain
    relationships, operations and the available
    information sources

34
IScape Builder (IB)
  • Provides a graphical interface to create and
    execute IScapes
  • Step1 select the ontologies that he/she wants,
    selection of the relationships

35
  • Step2 specify functions that operate on
    attributes
  • step3 specify the conditions that make up the
    structure of IScape
  • Step 4 specify additional constraints on the way
    the result of the IScape query should be groupd
  • Step5 specify the runtime projection parameters

36
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37
References
  • Amith Sheth, Sanjeev Thacker and Shuchi Patel,
    complex Relationships and knowledge Discovery
    support in the InfoQuilt system
  • Amith Sheth, I.Budak Arpinar, and Vipul Kashyap,
    Relatiosships at the heart of semantic Web
    Modeling, Discovering, and Exploiting complex
    semantic relationships
  • R. J. Bayardo Jr., W. Bohrer, R. Brice, et al.
    InfoSleuth Agent-Based Semantic
  • Integration of Information in Open and Dynamic
    Environments. In SIGMOD-97,pp. 195-206, Tucson,
    AZ, USA, May 1997.
  • C. Bertram. InfoQuilt Semantic Correlation of
    Heterogeneous Distributed
  • Assets. Masters Thesis, Computer Science
    Department, University of Georgia,1998.

38
References
  • Alexandria Digital Earth Prototype.
    http//www.alexandria.ucsb.edu/
  • S. Adali and R. Emery. A uniform framework for
    integrating knowledge in heterogeneous systems.
    Proceedings of the Eleventh IEEE International
    Conference of Data Engineering (March 1995).
  • Y. Arens, C. Hsu and C. A. Knoblock. Query
    processing in the SIMS
  • information mediator. In Austin Tate, editor,
    Advanced Planning Technology.The AAAI Press,
    Menlo Park, CA, 1996.
  • J. Ambite, and C. Knoblock. Planning by
    Rewriting Efficiently generating highquality
    plans. Proceedings of the 14th National
    Conference on Artificial Intelligence,
    Providence, RI, 1997.
  • Y. Arens, C. A. Knoblock, and W. Shen. Query
    reformulation for dynamic information
    integration. Journal of Intelligent Information
    Systems, Vol. 6, pp. 99-130, 1996.

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