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					     Exploiting Semantics of Web
     Services in eBusiness
     Applications
               Asuman Dogac
               Middle East Technical University
               06531 Ankara Turkey


Asuman Dogac           RIDE 2004, Boston, March 28, 2004   1/92
Outline
   Why do we need the semantics of Web services?

   Means of expressing semantics: Ontology and Ontology Description
    Languages

   Semantic Support Available in UDDI Registries

   Semantic Support Available in ebXML Registries

   Two approaches to exploiting semantics: Querying and Reasoning

   Describing the semantics of Web services in two domains
       Healthcare
       Tourism Industry


Asuman Dogac               RIDE 2004, Boston, March 28, 2004      2/92
     Why do we need the semantics
     of Web services?




Asuman Dogac   RIDE 2004, Boston, March 28, 2004   3/92
Why do we need Web Service
Semantics?
   WSDL only gives the technical specification of the Web services

   In order to exploit services in their full potential their properties
    must be defined:

       The methods of charging and payment
       The channels by which the service is requested and
        provided
       Constraints on temporal and spatial aspects
       Availability
       Service quality
       Security, trust and rights attached to a service

Asuman Dogac                RIDE 2004, Boston, March 28, 2004               4/92
Why do we need Web Service
Semantics?
   To be able to define the
    Web service functionality
    semantics                                                Defining
                                                             Service
   To be able to describe                                   Properties
    service properties and later                             Through
    search for services
    according to their properties                            Ontology
                                                             Languages
   This search needs to be
    done in a machine
    processable and
    interoperable manner


Asuman Dogac             RIDE 2004, Boston, March 28, 2004            5/92
     Ontology




Asuman Dogac    RIDE 2004, Boston, March 28, 2004   6/92
 What is an Ontology?
“An explicit formal specification of the terms in the domain and
relations among them.”
                - Noy and McGuinness, “Ontology Development 101”


   • The word ontology comes from the Greek ontos                  Class
   (being) and logos (word)
   •An ontology describes objects and concepts                              Subclass
   as classes
                                                                            Subclass
   • These classes are arranged in a hierarchy,
   and then class attributes and relationships are             properties              properties

   described with properties




 Asuman Dogac              RIDE 2004, Boston, March 28, 2004                              7/92
      Why use an ontology?

     • A common vocabulary
     • Ability to define relationships among classes,
       properties and instances
     • Automated Processing
           1. Querying
           2. Reasoning



Asuman Dogac             RIDE 2004, Boston, March 28, 2004   8/92
Resource Description Framework (RDF)

   A W3C recommendation

   RDF fixes the syntax and structure of describing
    metadata through RDF Syntax

   It allows meaning to be defined and associated with
    data through RDF Schema

   RDF Schema facilities to define domain specific
    ontologies


Asuman Dogac         RIDE 2004, Boston, March 28, 2004   9/92
Ontology Languages and OWL

    DAML:Darpa Agent                          OIL: Ontology Inference
     Markup Language                             Layer (European
                                               Commission Project)



                            DAML+OIL
                                                               RDF (Resource
                                                                Description
                                                                Framework)
                       OWL: Web Ontology
                         Language (Being
                       Standardized by W3C)



Asuman Dogac              RIDE 2004, Boston, March 28, 2004                10/92
OWL Classes

   Ministry of Interior has                     <owl:Class rdf:ID=“Crimes">
                                                 </owl:Class>
    defined ontologies for
    their information in OWL
   For example:                                              Crimes

                                             Robbery          Speeding   Terrorism

<owl:Class rdf:ID=“Robbery">
      <rdfs:subClassOf
rdf:resource="#Crimes"/>
                                         …        <owl:Class rdf:ID=“Terrorism">
                                                        <rdfs:subClassOf
                                                  rdf:resource="#Crimes"/>
</owl:Class>
                                                  </owl:Class>




Asuman Dogac              RIDE 2004, Boston, March 28, 2004                    11/92
OWL Properties
<owl:DatatypeProperty rdf:ID=“description">                            description
          <rdfs:domain rdf:resource="#Crime"/>
          <rdfs:range
   rdf:resource=“http://www.w3.org/2001/XMLSche             Crimes                   Literal
    ma#Literal"/>
</owl:DatatypeProperty >


<owl:ObjectProperty rdf:ID=“suspect">                                    suspect
           <rdfs:domain
    rdf:resource="#Robbery"/>                              Robbery                   Thief
           <rdfs:range rdf:resource=“#Thief>
</owl:ObjectProperty >

                                                                           driver
<owl:ObjectProperty rdf:ID=“driver">                        Speeding                 Speeder
           <rdfs:domain
    rdf:resource="#Speeding"/>
           <rdfs:range rdf:resource=“#Speeder"/>
</owl:ObjectProperty >


Asuman Dogac                       RIDE 2004, Boston, March 28, 2004                           12/92
An Example: eGovernment

   Finger prints from a robbery
    scene identified John Smith as
    the suspect

   Here is the police report on the
    robbery:

<Robbery rdf:ID="report-2003-10-23-xyz">
  <description>...</description>
  <suspect>
  <Thief
rdf:about="http://www.ministryOfInterior.gov/criminals#John_Smith"/
> </suspect>
</Robbery>

Asuman Dogac             RIDE 2004, Boston, March 28, 2004       13/92
An Example: eGovernment
• Later in the day a police gives a person a
  ticket for speeding

• The driver's license showed the name John
  Doe

• Here is the police report on the speeder:

<Speeding rdf:ID="report-2003-10-23-abc">
  <description>...</description>
  <driver>
     <Speeder
rdf:about="http://www.ministryOfInterior/criminals#John_Doe"/>
  </driver>
</Speeding>


Asuman Dogac             RIDE 2004, Boston, March 28, 2004       14/92
  Any Relationship between the Thief and
  the Speeder?

 Ministry of Interior keeps the OWL descriptions of their files:
<Criminals rdf:about="
        http://www.ministryOfInterior/criminals#John_Doe ">
  <owl:sameAs rdf:resource="
        http://www.ministryOfInterior.gov/criminals#John_Smith "/>
</Criminals>




Asuman Dogac            RIDE 2004, Boston, March 28, 2004      15/92
    How can this be achieved? owl:sameAs
    property helps!

                Thief               John Smith

                                              owl:sameAs

               Speeder               John Doe


         Inference: The Thief and the Speeder are one and
         the same!

   OWL provides a property (owl:sameAs) for indicating
    that two resources (e.g., two people) are the same

Asuman Dogac             RIDE 2004, Boston, March 28, 2004   16/92
     Semantic Support of Web Services in
     UDDI Registries




Asuman Dogac    RIDE 2004, Boston, March 28, 2004   17/92
    UDDI Registry APIs

   Inquiry API                                   Publishers API
       Find                                            Save
              find_business                                  save_business
              find_service                                   save_service
              find_binding                                   save_binding
              find_tModel                                    save_tModel
       Get Details                                     Delete
              get_businessDetail                             delete_business
              get_serviceDetail                              delete_service
              get_bindingDetail                              delete_binding
              get_tModelDetail                               delete_tModel




Asuman Dogac                    RIDE 2004, Boston, March 28, 2004                18/92
Defining Service Semantics in UDDI
Registries                                                               Contact
                                                                       Contact
                                                                          Phone
                                           businessEntity               Phone
                                                                          Address
                                                                        Address
         By using standard                  businessKey                  Email
                                                                        Email
                                             name
          taxonomies                         URL
                                             description
                                                                    businessService
                                                                  businessService
                                             contacts                serviceKey
                                                                   Key
                                             businessServices        tModelKey
         And by putting the                                       Name
                                             identifierBag           Name
                                                                   Description
          corresponding                      categoryBag             Description
                                                                   BindingTemplates
                                                                     BindingTemplates
          tModel keys in the                                    keyedReference
                                                                 keyedReference
          category bags of                                       tModelKey
                                                                  tModelKey
                                         keyedReference          keyName
                                        keyedReference            keyName
          services                        tModelKey              keyValue
                                                                  keyValue
                                         tModelKey
                                          keyName
                                         keyName
                                          keyValue
                                         keyValue



Asuman Dogac            RIDE 2004, Boston, March 28, 2004                      19/92
Business categories in UDDI
     Three standard taxonomies in V1

              Industry: NAICS - North American Industrial
               Classification Scheme (Industry codes - US Govt.)

              Product/Services: UN/SPSC - Universal Standard
               Products and Services Classification (ECMA)

              Location: ISO 3166 Geographical taxonomy




Asuman Dogac              RIDE 2004, Boston, March 28, 2004   20/92
ISO 3166 Codes (Countries)
(http://www.iso.ch/iso/en/prods-services/iso3166ma/)
Country        A2                    A3                 Number


ITALY          IT                    ITA                380


TURKEY         TR                    TUR                792


…              …                     …                  …


Asuman Dogac        RIDE 2004, Boston, March 28, 2004            21/92
North American Industry Classification
System (NAICS)




Asuman Dogac   RIDE 2004, Boston, March 28, 2004   22/92
United Nations Standard Products &
Services Code® (UNSPSC)




Asuman Dogac   RIDE 2004, Boston, March 28, 2004   23/92
How can we find a service through its
semantics in UDDI Registries?
   Looking for a service to buy a Computer

       If a service puts the tModel key corresponding to
        [43.17.18.03] Workstations or desktop computers –
        commodity in its category bag
       THEN
       We know that this service is related with computers
       BUT: Is this service really selling computers? If so how
        about the properties of the product? Payment
        method? Memory, Speed?

Asuman Dogac             RIDE 2004, Boston, March 28, 2004   24/92
Taxonomies Define Only Class/Subclass
Relationship: An Example Taxonomy: UNSPSC
• UDDI uses
taxonomies to describe
                                                           43.00.00.00.00
the semantic of Web                                 Communications and Computer
services by relating them                           Equipment and Peripherals and
to tModels                                            Components and Supplies


Through taxonomies:
                                                          43.16.17.00.00
• It is not possible to define                   Business Transaction and Personal
properties of services                                  Business Software

• It is not possible to relate
service classes with one                                     43.16.17.02.00
another                                                 Tax Preparation Software




Asuman Dogac                     RIDE 2004, Boston, March 28, 2004                   25/92
     Semantic Support of Web Services in
     ebXML Registries




Asuman Dogac    RIDE 2004, Boston, March 28, 2004   26/92
Where to store the generic semantics of
the services?
   An ebXML registry allows to define semantics
    basically through two mechanisms:
       It allows properties of registry objects to be
        defined through “slots” and,
       Metadata can be stored in the registry through a
        “classification” mechanism




Asuman Dogac           RIDE 2004, Boston, March 28, 2004   27/92
  ebXML Registry Information Model
  (RIM)
                       RegistryObject



 ClassificationNode    Classification           RegistryEntry     Association




ClassificationScheme    RegistryPackage              ExtrinsicObject    Service




  Asuman Dogac             RIDE 2004, Boston, March 28, 2004                    28/92
    Exploiting semantics                                        TravelService

                                               Transportation Accommodation Entertainment
                                                  Service         Service      Service

                                          AirTransportation
    In relating the semantics
     with the services advertised
     in service registries, there
                                        ReserveAFlight    BuyATicket

                                    originatingFrom destinationTo paymentMethod
                                                                                             ?
     are two key issues:
      Where to store the
        generic semantics of the
        services: In ebXML,                        ReserveAFlight
        metadata is stored in
        the registry
                                   originatingFrom destinationTo paymentMethod
      How to relate the services
        advertised in the registry
        with the semantic defined                              ?
        through an ontology: In
        ebXML through               MyService
        Classification objects

    Asuman Dogac                RIDE 2004, Boston, March 28, 2004                           29/92
Relating a Web service Advertised
with Service Ontology in ebXML
                  ServiceToIndustryClassification:
                           Classification


          classsifiedObject                                     classificationNode


            MyService:                                    ReserveAFlight:
           Registry Entry                                ClassificationNode




Asuman Dogac                RIDE 2004, Boston, March 28, 2004                        30/92
How to relate services advertised with
the generic ontology classes?
   By relating a service advertised with a node in classification
    hierarchy, we make the service an explicit member of this node

   The service also inherits the well-defined meaning associated
    with this node as well as the generic properties defined for this
    node

   When we associate “MyService” with “ReserveAFlightService”,
    its meaning becomes clear; that this service is a flight
    reservation service

   Assuming that the “ReserveAFlightService” service has the
    generic properties such as “originatingFrom”, “destinationTo”
    and “paymentMethod”, “MyService” also inherits these
    properties


Asuman Dogac              RIDE 2004, Boston, March 28, 2004       31/92
     Querying vs. Reasoning




Asuman Dogac   RIDE 2004, Boston, March 28, 2004   32/92
Some Observations
   Ontologies can play two major roles in the Web
    services area:

       One is to provide a source of shared and precisely
        defined terms which can be used to dynamically
        discover, compose and monitor services

       The other is to reason about the ontologies




Asuman Dogac           RIDE 2004, Boston, March 28, 2004   33/92
Some Observations

   The fact is that we do not have industrial strength
    reasoners yet!

   Semantic can also be taken advantage of through
    querying




Asuman Dogac          RIDE 2004, Boston, March 28, 2004   34/92
Exploiting Semantics through Querying

   Once semantics is associated with Web services in
    ebXML registries, it can be used to discover
    services simply through queries

   Examples:
       It is possible to find the properties of a Web service class

       It is possible to find all the advertised instances of a Web
        service class in the ontology

       It is possible to obtain the content files (WSDL and OWL)


Asuman Dogac               RIDE 2004, Boston, March 28, 2004       35/92
Querying ebXML Registry through Query
Templates
   This can be achieved through predefined query
    templates which yields into automation:

       A query template is used to obtain the properties of a
        generic class

       A query template is used for locating service instances of a
        given generic class node in the class hierarchy

       A template is a content retrieval query to obtain the original
        OWL and WSDL files through the identifiers of the OWL
        and WSDL files in the SpecificationLinks

Asuman Dogac               RIDE 2004, Boston, March 28, 2004       36/92
     A query template to obtain the properties of a generic class

                                    ebXML Registry

                                           TravelService

                           Transportation Accommodation Entertainment                        DatatypeProperty
                              Service         Service      Service

                       AirTransportation

                          ReserveAFlight
                                                                                             ObjectProperty
                                               BuyATicket



                   originatingFrom destinationTo                          promotion
                                                     paymentMethod



     ebXML Query                      1                           1            ebXML Query
Get Datatype Properties                                                    Get Object Properties

 ebXML Query Result                        2                  2             ebXML Query Result
   originatingFrom                                                           paymentMethod


   destinationTo                                                             promotion
Asuman Dogac                          RIDE 2004, Boston, March 28, 2004                              37/92
An Example Query Retrieving all the Associations of Type
“DatatypeProperty” for “ReserveAClassFlightService”
<AdhocQueryRequest xmlns =
"urn:oasis:names:tc:ebxml-regrep:query:xsd:2.0" xmlns:xsi =
"http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation =
"urn:oasis:names:tc:ebxml-regrep:query:xsd:2.0 query.xsd">
      <ResponseOption returnType = "LeafClass" returnComposedObjects = "true" />
      <FilterQuery> <ClassificationNodeQuery> <SourceAssociationBranch>
            <AssociationFilter> <Clause>
               <SimpleClause leftArgument = "associationType">
                  <StringClause stringPredicate = "Equal">
                                DatatypeProperty</StringClause>
                 </SimpleClause> </Clause>
             </AssociationFilter>
         <ClassificationNodeQuery> <NameBranch>
            <LocalizedStringFilter> <Clause> <SimpleClause leftArgument = "value">
                        <StringClause stringPredicate = "Contains">
                                           ReserveAFlightService</StringClause>
                   </SimpleClause> </Clause> </LocalizedStringFilter> </NameBranch>
        </ClassificationNodeQuery> </SourceAssociationBranch>
    </ClassificationNodeQuery> </FilterQuery> </AdhocQueryRequest>


Asuman Dogac                   RIDE 2004, Boston, March 28, 2004                 38/92
A query template to find all the advertised instances of a Web
service class
                                  ebXML Registry

                                         TravelService

                        Transportation       Accommodation Entertainment
                           Service               Service      Service
                    AirTransportation

                       ReserveAFlight         BuyATicket


                  MyService1        MyService2             MyService3




                                         1            ebXML Query
                                                   Get Extension of a
                                                   ClassificationNode

                                   2              ebXML Query Result
                                                  MyService1
                                                                    MyService3
                                                  MyService2
   Asuman Dogac                 RIDE 2004, Boston, March 28, 2004                39/92
An Example Query: Retrieving all the Services Classified
with “ReserveAFlightService” ClassificationNode

<AdhocQueryRequest
 xmlns = "urn:oasis:names:tc:ebxml-regrep:query:xsd:2.0"
 xmlns:xsi = "http://www.w3.org/2001/XMLSchema-instance"
 xsi:schemaLocation = "urn:oasis:names:tc:ebxml-regrep:query:xsd: 2.0 query.xsd">
 <ResponseOption returnType = "LeafClass" returnComposedObjects = "true" />
  <FilterQuery> <ServiceQuery> <ClassifiedByBranch>
     <ClassificationNodeQuery>
       <NameBranch>
        <LocalizedStringFilter>
          <Clause>
           <SimpleClause leftArgument = "value">
            <StringClause stringPredicate = "Equal"> ReserveAFlightService
            </StringClause>
           </SimpleClause> </Clause> </LocalizedStringFilter> </NameBranch>
     </ClassificationNodeQuery> </ClassifiedByBranch> </ServiceQuery>
    </FilterQuery>
</AdhocQueryRequest>



Asuman Dogac                  RIDE 2004, Boston, March 28, 2004                     40/92
                     ebXML Registry                                               ebXML Repository


                      TravelService                                             WSDL of     OWL-S of
                                                                               MyService1   MyService1
    Transportation     Accommodation         Entertainment
       Service             Service              Service

AirTransportation
                                                              Extrinsic
                                                               Object
   ReserveAFlight           BuyATicket

                                   SpecificationLink          Extrinsic
                                                               Object
               MyService1




                              1              ebXML Query                       A Content Retrieval
                                         Get SpecificationLink                 Query template
                                         Content of a Service
                        2
                                         ebXML Query Result

                                          WSDL of           OWL-S of
                                         MyService1         MyService1

Asuman Dogac                               RIDE 2004, Boston, March 28, 2004                      41/92
Retrieving the WSDL Files
<GetContentRequest
    xmlns="urn:oasis:names:tc:ebxml-regrep:query:xsd:2.1"
    xmlns:rim="urn:oasis:names:tc:ebxml-regrep:rim:xsd:2.1"
    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xsi:schemaLocation="urn:oasis:names:tc:ebxml-regrep:rim:xsd:2.1
    ../schema/rim.xsd urn:oasis:names:tc:ebxml-regrep:query:xsd:2.1
    ../schema/query.xsd">
          <rim:ObjectRefList>
          <--! The unique id of the WSDL file in the registry -->
          <rim:ObjectRef
              id="urn:uuid:7e4397db-916a-490f-bdc7-c9da"/>
          </rim:ObjectRefList>
</GetContentRequest>




Asuman Dogac             RIDE 2004, Boston, March 28, 2004            42/92
     OWL-S




Asuman Dogac   RIDE 2004, Boston, March 28, 2004   43/92
OWL-S: Defines an Upper Ontology for
Web Services in OWL

        Resource                                    ServiceProfile


                                                             presents: What it
                   provides
                                                                does
                               Service
                                                               describedBy:How it
                                                                 works
    ServiceGrounding
                       Supports:                       ServiceModel
                       How to access it



Asuman Dogac             RIDE 2004, Boston, March 28, 2004                       44/92
     Web services and the
     Healthcare Domain




Asuman Dogac   RIDE 2004, Boston, March 28, 2004   45/92
Challenges of Healthcare Informatics

   According to Jonathan Borden, M.D. of ASTM:

        A disaster: 1.1 Trillion $/year in the USA
        30-40 % overhead
        Mostly paper based
        Highly proprietary commercial systems
        Tens of thousands of people die each year due to poor
         information/errors
        Most of the information is rendered useless




Asuman Dogac               RIDE 2004, Boston, March 28, 2004     46/92
Asuman Dogac   RIDE 2004, Boston, March 28, 2004   47/92
Challenges of Healthcare Informatics

   Most of the health information systems today are
    proprietary

   They often only serve one specific department within a
    healthcare institute

   To complicate the matters worse, a patient's health
    information may be spread out over a number of different
    institutes which do not interoperate

   This makes it very difficult for clinicians to capture a
    complete clinical history of a patient

Asuman Dogac            RIDE 2004, Boston, March 28, 2004      48/92
Patient Records: Problems


          Content: too little, too much, or wrong

          Format: poor organization of information

          Access, availability, security

          Linkages and integration




Asuman Dogac             RIDE 2004, Boston, March 28, 2004   49/92
Challenges of Healthcare Informatics


        The systems must interoperate for effectiveness
        For interoperability standards are needed
        However there are more than one standard in the
        health care domain




Asuman Dogac            RIDE 2004, Boston, March 28, 2004   50/92
EHR Architectures
The nice thing about standards is that there are so many to
choose from.
Andrew Tanenbaum, Introduction to Computer Networks
   „Candidates“ of EHR architectures:
       CEN ENV 13606 „EHR Communication“
       Good Electronic Health Record (GEHR)
       OpenEHR
       CEN EN 13606 (draft)
       HL7 Clinical Document Architecture
       HL7 v2 Information Model (implicit)
       HL7 v3 Reference Information Model (draft)

Asuman Dogac            RIDE 2004, Boston, March 28, 2004     51/92
Web Services in the Healthcare
Domain
   Web services provides the healthcare industry with an ideal
    platform to achieve the difficult interoperability problems

   Web services are designed to wrap and expose existing
    resources and provide interoperability among diverse
    applications

   It becomes possible to provide the interoperability of medical
    information systems through standardizing the access to data
    through WSDL and SOAP rather than standardizing
    documentation of electronic health records



Asuman Dogac             RIDE 2004, Boston, March 28, 2004        52/92
Introducing Web services to the healthcare
domain brings many advantages
       Medical information systems suffer from proliferation of
        standards to represent the same data; Web services allow
        for seamless integration of disparate applications
        representing different and, at times, competing
        standards

       Web services will extend the healthcare enterprises by
        making their own services available to others

       Web services will extend the life of the existing software
        by exposing previously proprietary functions as Web
        services

Asuman Dogac              RIDE 2004, Boston, March 28, 2004      53/92
Semantics of Web Services

   In order to exploit Web services to their full potential, it is
    necessary to describe their semantics

   An essential element in defining the semantic of Web
    services is the domain knowledge

   Medicine is one of the few domains to have extensive
    domain knowledge defined through standards




Asuman Dogac             RIDE 2004, Boston, March 28, 2004      54/92
Domain Knowledge

   Some of the domain knowledge exists in controlled
    vocabularies, or terminologies:
     Some vocabularies are rich semantic nets, such as SNOMED-CT

      while others such as ICD-10 (International Statistical
      Classification of Diseases and Related Health Problems) is
      little more than lexicons of terms
     However, there are also standards that expose the business

      logic in the healthcare domain such as HL7 and Electronic
      Healthcare Record based standards such as CEN TC251, ISO
      TC215 and GEHR which define and classify clinical concepts
   These standards offer significant value in developing
    ontologies to express the semantics of Web services



Asuman Dogac            RIDE 2004, Boston, March 28, 2004     55/92
What kind of Semantics?
   Service Functionality Semantics:
     HL7 has categorized the events in healthcare domain by

      considering service functionality which reflects the business logic
      in this domain
     This classification can be used as a basis for defining the service

      action semantics through a Service Functionality Ontology
   Service Message Semantics:
     Electronic healthcare record (EHR) based standards like HL7

      CDA (Clinical Document Architecture), GOM (GEHR Object
      Model), and CEN TC251's ENV 13606 define meaningful
      components of EHR so that when transferred, the receiving
      party can understand the record content better
     The meaningful components defined by these standards can

      be used in developing service message ontologies

Asuman Dogac               RIDE 2004, Boston, March 28, 2004          56/92
HL7 and Web Services
   The primary goal of HL7 is to provide standards for the exchange
    of data among healthcare computer applications

   An event in the healthcare world, called the trigger event, causes
    exchange of messages between a pair of applications

   When an event occurs in an HL7 compliant system, an HL7
    message is prepared by collecting the necessary data from the
    underlying systems and it is passed to the requestor, usually as
    an EDI message

   Mapping HL7’s message based events directly into Web services
    may result in several inefficiencies


Asuman Dogac              RIDE 2004, Boston, March 28, 2004        57/92
HL7 and Web Services
   The input and output messages defined for HL7 events are
    usually very complex containing innumerous segments of
    different types and optionality
   Furthermore, all the semantics about the business logic and
    the document structure are hard coded in the message
   This implies that, the party invoking the Web service must be
    HL7 compliant to make any sense of the content of the output
    parameter(s) returned by the service
   Furthermore, the information contained in an HL7 message may
    be coming from different systems either proprietary or
    complying to different standards
   Hence, in Web services terminology, HL7 events correspond to
    Composite services, whereas more elementary services are
    needed

Asuman Dogac            RIDE 2004, Boston, March 28, 2004     58/92
HL7 and Web Services

   Since HL7 has already been through an effort
    of categorizing the events in healthcare
    domain considering service functionality, it
    can be used as a basis for a service
    functionality ontology




Asuman Dogac      RIDE 2004, Boston, March 28, 2004   59/92
     An Example Service Functionality
     Ontology
                                       HealthCareServices

PatientAdministration   PatientCare         PatientReferral               Scheduling    ObservationReporting


             PatientReferralRequest       PatientInfoRequest                   CancelPatientReferral

                    InsuranceInformation       ClinicalInformation             DemographicData


                                  GetClinicalInformation



                            serviceQuality                     location                Properties of the
                                                                                       Generic Service
                                                                                       Class

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Service Messages
   A Web service in the healthcare domain usually accesses or
    updates a part of an electronic healthcare record, that is,
    parts of the EHR constitute the service parameters
   An electronic healthcare record may get very complex with data
    coming from diverse systems such as lab tests, diagnosis,
    prescription of drugs which may be in different formats
   Electronic healthcare record (EHR) based standards like HL7
    CDA, GOM and CEN's ENV 13606 aim to facilitate the
    interoperability between Medical Information Systems
   These standards provide conceptual building blocks or
    meaningful components
   We propose to use these standards as a basis for Service
    Message Ontology


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GEHR

      EHR and Transaction level
      Navigation level
      Content (e.g. observation, subjective,
       instruction) level
      Data types (e.g. quantity, multimedia) level
      Clinical models are expressed outside the
       GOM in the form of archetypes


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CEN TC 251 ENV 13606
      Folder: High-level subdivisions of the entire EHR for a patient

      Composition: A set of record entries relating to one time and
       place of care delivery; grouped contributions to an aspect of
       health care activity; composed reports and overviews of clinical
       progress

      Headed Section: Sub-divisions used to group entries with a
       common theme or derived through a common healthcare
       process.

      Cluster: Low-level aggregations of elementary entries (Record
       Items) to represent a compound clinical concept


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An example Service Message
Ontology




                                                   Concept

                                                   Property




Asuman Dogac   RIDE 2004, Boston, March 28, 2004   64/92
  Relating the services with the
  semantic defined through an ontology - UDDI



  UDDI Business Entities and Related
HacettepeHospital
                                                                      UDDI tModels
           ObservationReportingServices                                Medical Services
                 .
                 .                                                                        PatientCare
                 .
                                                                  PatientReferral
                                                                                    Observation
            PatientReferralServices                                                  Reporting
                                                   GetClinicalInfo
                                                                          PatientReferralReq
                     getClinicalInfo


                               CategoryBag reference


  Asuman Dogac                    RIDE 2004, Boston, March 28, 2004                                65/92
    Associating semantics to ebXML
                                          HealthCareServices
                                                                      subclassOf
                                    subclassOf
                     PatientCare                                           PatientAdministration
                                          ObservationReporting
       subclassOf            subclassOf


PatientReferralRequest         PatientInfoRequest




                                             Standards
                   serviceQuality            Conformed
                                                                            ebXML Classification
                                                                                Hierarchy
                                    ebXML
            ebXML
     ClassificationNodes            associations
                                                                    ebXMLslots

    Asuman Dogac                       RIDE 2004, Boston, March 28, 2004                           66/92
The healthcare informatics industry has
already started using Web services

   An Example: Integrating the Healthcare
    Enterprise (IHE)

   IHE defines a Web service based
    implementation framework




Asuman Dogac      RIDE 2004, Boston, March 28, 2004   67/92
   Overview of IHE IT Infrastructure
         Integration Profiles



               IHE IT Infrastructure Technical Committee
      Charles Parisot, GE Medical Systems Information Technologies
Asuman Dogac               RIDE 2004, Boston, March 28, 2004         68/92
  IHE IT Infrastructure
  5 Integration Profiles
      Retrieve Information
           for Display                                                          Enterprise User
                                              Patient Synchronized              Authentication
        Access a patient’s clinical
    information and documents in a                Applications
      format ready to be presented
                                           Synchronize multiple applications
         to the requesting user
                                           on a desktop to the same patient



                                                                               Provide users a single
                                                                                        name
        Patient Identifier                                                               and
                                                   Consistent                       centralized
       Cross-referencing
                                                     Time                      authentication process
             for MPI                                                             across all systems


        Map patient identifiers                   Coordinate time
          across independent                     across networked
        identification domains                       systems




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 An Example: Retrieve Information for Display

Key Technical Properties:
 Standards Used:
    Web Services (WSDL for HTTP Get).

    General purpose IT Presentation Formats: XHTML, PDF,
     JPEG plus CDA L1.
    Client may be off-the-shelf browser or display app.

 Two services :
    Retrieve of Specific Information:
                  Patient centric: patient ID
                  Type of Request
                  Date, Time, nMostRecent
         Retrieve a Document
                  Object Unique Instance Identifier (OID)
                  Type of Request
                  Content Type Expected



Asuman Dogac                        RIDE 2004, Boston, March 28, 2004   70/92
 Retrieve Information for Display
Transaction Diagram
               Retrieve Specific Info for Display [11]      Information
     Display
                                                            Source

               Retrieve Document for Display [12]


               Summary of All Reports
               Summary of Laboratory Reports
               Summary of Radiology Reports
               Summary of Cardiology Reports
Types of       Summary of Surgery Reports
               Summary of Intensive Care Reports
Requests       Summary of Emergency Reports
               Summary of Discharge Reports
               List of Allergies

               List of Medications
               Persistent Document
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For Further Information…
   IST-1-002103-STP Artemis Project: A
    Semantic Web Service-based P2P
    Infrastructure for the Interoperability of
    Medical Information Systems

   http://www.srdc.metu.edu.tr/artemis/




Asuman Dogac           RIDE 2004, Boston, March 28, 2004   72/92
     Web Services and the Travel
     Industry




Asuman Dogac   RIDE 2004, Boston, March 28, 2004   73/92
     Overall Information Flow in
     Tourism Domain About 1000 companies

   About                                                 4 major GDSs+
                     Hundreds Airline Companies
  100,000                          Olympic, Air France …    10 small
                         Of
   Hotels             Chains                                                   E-Comm.
                                  Two companies                      XML
                                                                                 Site
                       Hotel
                      Chains         Switching
                                    Companies
  Hotels             Hilton, BW,                           GDS                  Travel
                                       Pegasus,                    Cryptic
                     Utell, E-Rez,
 Hilton Ankara,
                     …                    Worldres.                Amadeus,    Agency
 Sofitel Paris ...                                                 Galileo,
                                                                   Sabre,
  Tens of                                                          Worldspan
Thousands                        Rent-a-Car Hundreds               …
Of agencies                       Chains        Of
                Rent-a-Car       Avis, Hertz, … Chains
                Agencies
     Asuman Dogac                     RIDE 2004, Boston, March 28, 2004             74/92
Global Distribution Systems (GDS)

   Provides connection to the airline, hotel and
    rent-a-car reservation systems from a single point

   Leading GDSs: Amadeus, Sabre, Galileo, Worldspan

   Travel Agency – GDS Connectivity
       Usually in the form of dedicated client terminals that accept
        GDS specific cryptic commands, connected to the GDS on a
        private network
       Special APIs provided for Client Application Developers



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Disadvantages of GDSs (I)

   But GDSs suffer from:

       Mostly they rely on their own private networks
       They have difficult to use cryptic languages
       Mainly for human use
       A request to the system usually involves more than one
        interaction with the person on the terminal
       GDSs have limited speed and search capabilities
       It is difficult to interoperate them with other systems and
        data sources


Asuman Dogac               RIDE 2004, Boston, March 28, 2004          76/92
Challenges of Travel Industry (II)

   GDSs are legacy systems and suffer from:
       Classical problems with centralized architectures
       Among the millions of travel agents, only about 10 to 20%
        of all travel agents are in connection with the GDS
        companies
       Weak support for SMEs (major hotel chains and etc..)
       Do not support every type of services
        in travel industry (no support for tours)




Asuman Dogac              RIDE 2004, Boston, March 28, 2004     77/92
A Web service based architecture can
bring several advantages to the industry

       Opening up the resources over the Internet
       Interoperability
       Ability to access legacy systems
       Better support for SMEs
       Ease in service discovery
       Machine processing
       Better accessibility


Asuman Dogac           RIDE 2004, Boston, March 28, 2004   78/92
Web Services in Travel Industry
   A few early adopters in the travel industry have started developing
    Web Services

                 Sabre and                                    Datalex are among

the first companies to develop OTA based Web services

   Sabre Web Services provide all the functionality needed to sell
    travel

   Galileo also provides a Web service based solution and claims
    to have cut down the development time by 80%



Asuman Dogac               RIDE 2004, Boston, March 28, 2004                  79/92
New Business Opportunities through Web
Services in the Travel Domain (I)
   GDS companies support only major travel products;
       Airline ticketing,
       Hotel reservation and
       Car rental

   Through Web services other types of specialized
    services can be made available

   Especially different types of tour and transportation
    based travel products can be advertised and
    accessed

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New Business Opportunities through Web
Services in the Travel Domain (II)
   Among the millions of travel agents, only about 10 to
    20% of all travel agents are in connection with the
    GDS companies

   Most travel agencies and travel organization
    companies choose to manage travel services by
    themselves, due to reasons which may be
       Technical, or
       Economical

   These companies generally suffer from the lack of
    advertising their services as well as publishing them
    electronically
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New Business Opportunities through Web
Services in the Travel Domain (III)
   Web services technology will provide a solution for
    all companies, especially for small-to-medium
    enterprises in the travel industry

   The travel agencies and service providers will
    collaborate with each other on a new level

   The companies will be able to provide every type of
    travel service; the service alternatives will be found
    on the fly

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Service Semantics in Travel
Domain
   Generic service semantics can be defined through
    DAML-S (later OWL-S) upper ontology

   However some other properties of the services
    depend on the application domain

   To facilitate the discovery of the Web services, there
    is a need for an ontology to describe service
    functionality in the domain


Asuman Dogac          RIDE 2004, Boston, March 28, 2004   83/92
Ontology Efforts in the Travel Domain


   There are some efforts in this direction

   There have been some efforts in defining the message
    ontologies in the travel domain such as the Harmonise
    project http://www.harmonise.org/

   The Harmonise project have defined the
    Interoperability Minimum Harmonization Ontology
    (IMHO)




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Open Travel Alliance (OTA)
   OTA exposes considerable amount of
    domain knowledge which can offer
    significant value in describing the
    semantics of travel Web services:
       Generic messages
       Air messages
       Car message
       Hotel messages
       Golf Tee Times
       Insurance messages
       Package Tours/Holiday Bookings
       Travel Itinerary messages
       Rail information messages
       Loyalty messages
       Profile messages

Asuman Dogac                RIDE 2004, Boston, March 28, 2004   85/92
   Service Functionality Ontology
          First Level          TravelWebServices



VehicleServices HotelServices RailServices                AirServices InsuranceServices .........



    ..........     .........    AirDetailsServices                              ..........
                                            AirBookingServices

                                                       AirScheduleServices

                                                                     CheckingAvailabilityServices


                                                                RequestAirAvail ResponseAirAvail

   Asuman Dogac                  RIDE 2004, Boston, March 28, 2004                           86/92
The advantages of Service
Functionality Ontology
   All sorts of Web services can be
    classified by using the nodes of such an
    ontology to make their meaning clear

   Web service instance discovery is
    facilitated: All the services classified
    through a node in the ontology can be
    retrieved from service registries




Asuman Dogac          RIDE 2004, Boston, March 28, 2004   87/92
Message Ontologies

   There is a need for message ontologies

   It is also necessary to define the semantics of the
    messages exchanged so that the party receiving the
    message can interpret it

   When ontologies are used to describe the
    messages, since the messages can refer to
    ontology concepts, it becomes possible to map one
    message instance into another through ontology
    mapping although they may be defined through
    different ontologies

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For Further Information…

   IST-1-002104-STP Satine Project:
    Semantic-based Interoperability
    Infrastructure for Integrating Web
    Service Platforms to Peer-to-Peer
    Networks

   http://www.srdc.metu.edu.tr/satine/




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Conclusions…

   Semantic information about Web services can be
    made use of both
       through querying the service registries and
       through reasoners running over ontologies

   Needless to say reasoning produces new
    information and hence is more powerful

   But given that we do not have industrial strenth
    reasoners yet; through querying the we can get very
    useful semantics on Web services

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Conclusions…

   The semantic efforts on the Web services area need
    to focus on application domains

   Semantics is domain specific knowledge

   Also different domains have evolved differently;
    and they have different needs

   Web service technology can improve the
    interoperability and can introduce new business
    models in these domains


Asuman Dogac         RIDE 2004, Boston, March 28, 2004   91/92
Thank you for your attention!




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