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The UPML Framework, IRS-I and IRS-II. John Domingue, Liliana Cabral & Enrico Motta Knowledge Media Institute The Open University, UK. Outline. Overview of web services UPML – knowledge level modelling paradigm Classification Library IRS-I Demo quickly configuring an apple classifier - PowerPoint PPT Presentation
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The UPML Framework, IRS-I and IRS-II
John Domingue, Liliana Cabral & Enrico Motta
Knowledge Media InstituteThe Open University, UK
Outline• Overview of web services• UPML – knowledge level modelling
paradigm• Classification Library • IRS-I Demo
– quickly configuring an apple classifier• IRS-II – capability driven web service
invocation• Patient Shipping Scenario (Demo)• Preparation for afternoon hands on session
Web Service in a nutshell
• Web of documents -> web of reusable software components
• A piece of software available over the Internet which can be invoked through a standardized (normally XML-based) messaging system
ServiceRegistry
ServiceRequester
ServiceProvider
ServiceDescription
WebService
PublishFind
Bind
WS – Usage scenario
What’s the big deal?• In U.S. Web Services Market Analysis, 2002 IDC
predicts that Web services will become the dominant distributed computing architecture in the next 10 years. Web services will drive software, services and hardware sales of $21 billion in the U.S. by 2007 and will reach $27 billion in 2010.
• Web services promise easy access to remote content and application functionality, independently of the provider's platform, the location, the service implementation, or the data format. Kuassi Mensah, Oracle
• Exposure of capabilities
Application Areas
• E-commerce– Integrating supply chains, Brokering, Shopping bots,
etc..
• E-science– Data Analysis, Discovery, Integration, etc..
• Knowledge Management– Information search, personalization,
Limitations of WS Technology
• Manual Discovery
• Manual Invocation
• Manual (ad hoc) Mediation
• Manual (ad hoc) Composition
Semantic differences remain the primary roadblock to smooth application integration, one which Web Services alone won't overcome. Until someone finds a way for applications to understand each other, the effect of Web services technology will be fairly limited. When I pass customer data across [the Web] in a certain format using a Web Services interface, the receiving program has to know what that format is. You have to agree on what the business objects look like. And no one has come up with a feasible way to work that out yet -- not Oracle, and not its competitors...
--- Oracle Chairman and CEO Larry Ellison
Positioning Semantic Web Services
Web(URI, HTML, HTTP)
Web Services(UDDI, WSDL, SOAP)
Semantic Web(RDF, OWL)
Semantic Web Services
Dynamic
Static
Syntax Semantics
Motivation• Mismatch between users view and web
service functionalities– Requires web service centred and user
(community) centred semantic representations• Users want to carry out tasks or achieve
goals• Richer semantics required for automatic
web service location, selection, mediation, composition, brokering
UPML Framework
UPML Framework
UPML Framework
Classification
Classification can be seen as the problem of finding the solution (class), which best explains a set of known facts (observables), according to some criterion
Solution
Observables
Candidate Sols.Classification
Solution Criterion
Example
Observables
Candidate Sols.
Criterion
Classification Solution
{background=green; area=china...}
Complete-coverage-criterion(every observable has to be explained)
{chinese-granny, dutch-granny, etc..}
{chinese-granny}
Classification Task Ontology
• 70 Definitions• Provides both a theory of
classification and a vocabulary to describe classification problems
• Ontology is separated from task specifications
Generic Classification Task• Input roles
– Candidate Solutions, Match Criterion, Solution Criterion, Observables
• Output Roles– Solutions
• Precondition– Both observables and candidate solutions have to be provided
• Goal– To find a solution from the candidate solutions which is admissible
with respect to the given observables, solution criterion and match criterion
Classification Task (1/2)
Classification Task (2/2)
Specific Classification Tasks
• Single-Solution Classification Task– Single-solution assumption
• Optimal Classification Tasks– Goal requires optimality
Problem Solving Library
• Based on heuristic classification model
• Includes both data-directed and solution-directed methods
• Supported by a method ontology
Heuristic Classification Model
Clancey, AI Journal, 27, 1985
Heuristic Match
Abstraction
Data
DataAbstractions
SolutionsAbstractions
Refinement
Solutions
Method Ontology: Main Concepts• Abstractors
– Mechanism for performing abstraction on observables
– Abstractor: Obs* -> Obs
• Refiners– Mechanism for specialising a solution– Refiner: Sol -> Sol*
• Candidate Exclusion Criterion– A criterion which is used to decide when a search
path is a dead-end– Default criterion rules out inconsistent solutions
3 Heuristic Classification PSMs• Two Data-directed
– Admissible Solution Classifier• Finds one admissible solution according to the given criteria• Uses backtracking hill climbing
– Optimal Classifier• Performs complete search looking for optimal solution• Uses best-first strategy• Uses candidate exclusion criterion to prune search space
• One Solution-directed– Goes down the solution hierarchy, acquiring observables as
needed– Ask for observables with max discrimination power
Task-Method Hierarchy
abstraction
heuristic-classification-psm
classification
rank-solutions refinement
basic-heuristic-matchselect-abstractor one-step-abstraction collect-refiners apply-refiners
abstraction-psm refinement-psmrank-solutions-psm
Example
• Apple Domain– Originally developed in Amsterdam
• Solutions = Apple Types = {granny, noble, delicious...}
• Hierarchy of Apple Types• Features = {bkg-colour, fg-colour,
rusty....}• Pretty trivial really!
Classification TaskOntology
Heuristic ClassificationOntology
Apple Heuristic ClassificationApplication
Classification TaskSpecification
Classification-to-Class-RepresentationMapping Ontology
AppleDomain Model
Heuristic ClassificationPSMs
Demo
IRS-II: Integrating UPML and Web Services
The Internet Reasoning Service is an infrastructure for publishing, locating, executing and composing semantic web services, organized according to the task/method/domain framework
Features of IRS-II (1/2)• Based on Soap messaging standard
• Provides API for client applications
• Provides built-in brokering and service discovery support
• Provides capability-centred service invocation
Features of IRS-II (2/2)• Publishing support for variety of platforms
– Java, Lisp, Web Applications, Java Web Services
• Enables publication of ‘standard code’ – Provides clever wrappers automatically, which turn code into
web services– One-click publishing of web services
• Integrated with standard Web Services world– Published code appears as
• Semantic web service to IRS• ‘Ordinary’ web service to web service world
Task Spec(def-class exchange_rate_provision (goal-specification-task) ?task ((has-input-role :value has_source_currency :value has_target_currency) (has-output-role :value has_exchange_rate) (has_source_currency :type currency :cardinality 1) (has_target_currency :type currency :cardinality 1) (has_exchange_rate :type positive-number) (has-precondition :value (kappa (?psm) (and (currency (role-value ?psm has_source_currency)) (currency (role-value ?psm
has_target_currency))))) (has-goal-expression :value (kappa (?psm ?sol) (= ?sol (the_official_exchange_rate (role-value ?psm has_source_currency) (role-value ?psm has_target_currency)))))))
Grounding
• Soap-based
• Done at task level
Toplevel Exchange Rate Method
(def-class exchange-rate-provider (primitive-method) ?psm
((has-input-role :value has_source_currency :value has_target_currency) (has-output-role :value has-exchange-rate) (has_source_currency :type currency :cardinality 1) (has_target_currency :type currency :cardinality 1) (has-exchange-rate :type positive-number) (has-precondition :value (kappa (?s) (stock_available
(role-value ?psm has_target_currency))))))
Exchange Rate Methods(def-class european-exchange-rate-provider (exchange-rate-
provider) ?psm () :own-slots ((applicability-condition (kappa (?psm) (european-currency (role-value ?psm 'has_source_currency)))) (tackles-task-type exchange_rate_provision)))
(def-class non-european-exchange-rate-provider (exchange-rate-provider) ?psm ()
:own-slots ((applicability-condition (kappa (?psm) (non-european-currency (role-value ?psm 'has_source_currency)))) (tackles-task-type exchange_rate_provision)))
IRS Server
Domain Models
Method Specifications+ Registry of Implementors
Task Specifications+ SOAP Binding
IRS Publisher
S O A
P
IRS Client
SOAP
IRS Publisher
IRS Publisher
IRS Publisher
Lisp
Java
Java WS
IRS-II Framework
Patient Shipping Scenario
Patient Shipping Scenario
Money Related Services
Medical Related Services
Patient Shipping Demo
Task Spec
Method Spec
Supporting Definitions
Hospital Bed Service Task
Hospital Bed Service PSM
Hip Hip Hospital PSM
Multiple Hospital PSMs
Valid Relations• Classes are unary relations
– e.g. (currency ?x)
• Slots are binary relations
– e.g. (has-author ?x ?y)
• Standard relations in akt-reference ontology
=, ==, <, >, member
Java API• achieveTask • createOntology • getOntologyProperties • updateOntologyProperties • deleteOntology • saveTaskDescription • getTaskDescription • deleteTaskDescription • savePSMDescription • getPSMDescription • deletePSMDescription • publishHttpGetRequest • publishLispFunction • publishJavaClass• publishWebServiceWSDL
LispWeb Server
IRS-II Architecture
IRS-II Server
PSM Publisher Registry
OCML
UPML Library
Wilbur
OWL-S Handler
OWL HandlerOWL
OWL-S
RDF
Browser
Invocation Client
Task/PSM Editors
Publishing Clients
SOAP Handler
SOAP
Publishing Platforms
Web ServiceJava CodeWeb Application
SOAP
BrowserHandler
PublisherHandler
InvocationHandler
Java
API
Generic Publishing Platform Architecture
IRS-II Publishing PlatformHTTP Server
SOAP Handler
ServiceRegistrar
ServiceInvoker
PSM Service Registry
IRS-II Server
Invocation Client
SOAP
SOAP
Publishing Clients
SOAP
Web Service 1Web Service 2
Web Service 3Web Service 4
IRS Browser/Editor Demo
User Name: knowledgewebPassword: summerschool
IRS, OWL-S and WSMO• IRS-II and WSMO model user requests
(task or goal)– IRS-II has task (goal) based invocation
• IRS-II and WSMO model mediation• OWL-S and WSMO include non-functional
properties• WSMO splits composition into
orchestration and choreography • Formalisms
– OWL-S: OWL – DL (handling conditions?)– IRS-II: OCML (import/export to RDF(S), OWL,
OWL-S, WSMO (planned))– WSMO: WSML- F-Logic (OWL Compatibility?)
Summary• Web services require rich semantic
annotation to automate location selection, mediation etc
• UPML framework composed of ontology supported tasks, problem solving methods and domain models
• Classification Library • IRS-II integrates web services with
PSMs• PSMs tied to tasks via tackles task and
applicability conditions
A Stack of Standards?
HTTP
XML-
SXM
L
SOAP
WSDL
UD
DI
BEP
L4W
S
URI
WS-
CDL
RDF
RDF-S
OWLWSML
OWL-SWSMO
WSMXIRS-III