Jakob Beetz, Bauke de Vries, Jos van Leeuwen Design Systems group TU/Eindhoven ● Distributed Collaboration in the Context of the Semantic Web Presentation for the 8 th DDSS conference, Heeze

Overview ● Motivation ● Overall system architecture ● DL-based BIM ● Query and partial model extraction ● Reasoning / inference ● Discussion & Outlook

Traditional Working Methods ● Traditional CA(A)D data is – Non-deterministic and ambiguous – Episodic – Highly dynamic – Continuous – Does not contain machine readable knowledge

Central Building Model ● Central Building Model – Founded on central databases – No specification for interaction – Assumes completeness – Appropriate for smaller projects?

MAS in heterogeneous environments

Motivation ● Develop semantically enhanced web services, assist Grid computing ● Profit from large set of research, methods and tools developed in other domains ● Use knowledge representation tools for modeling ● Facilitate distribution of information across networks

Performance estimation use case in a MAS

Topological inference task example IfcWallStandardCase #949= IFCSPACE(‘guid1',#13,'1',$,$,#947,#939, 'big_room',.ELEMENT.,.INTERNAL.,$); IfcSpace #97= IFCWALLSTANDARDCASE(‘fooGuid',#13, 'Wand-035',$,$,#95,#153,$); IfcRelSpaceBoundary (as IfcConnectionSurfaceGeometry) ???

Chain of agents for the sceneario

Storing a model as ifcOWL

Different Knowledge Domains in AEC/FM project ● ERM ● Semantic Networks ● Frame based systems ● DL based systems

Architecture diagram of IFC 2x2

IfcOWL as KRS KRS = Terminology (TBox ) + Assertational Knowledge (ABox) K = ( T, A )

Basic AL constructs AL Attribute Language Atomic concepts C,D Atomic Roles R,S Terminological Axioms: Equality C º D (used to describe definitions) Inclusion / Supsumption C m D (used to describe IS-A realtions)

Basic AL constructs Terminological Axioms (cntd.): Intersection C * D Woman º Person * Female Existential quantification $ R.C Mother º Woman * $ hasChild.Person Value Restriction " R.C MotherOfDaughtersOnly º Woman * " hasChild.(Person * Female)

Semantic Web Stack Semantic Web Structure according to Tim Berners-Lee

RDF-based representations Ora Lassila is the creator of the resource N3 noation: “Ora Lassila” isCreatorOf w3.org/Home/Lassila Ora Lassila PredicateSubjectObject

IfcOWL T-Box in Protege

IfcOWL A-Box in Protege

IfcOWL Please find the Technical specification details of ifcOWL in Gehre, A. Katranuschkov, P. Wix, J. and Beetz, J. (2006). InteliGrid Deliverable D31: Ontology Specification, The InteliGrid Consortium, c/o University of Ljubljana,

Extracting partial models

Partial Model extraction e.g. using SPARQL

Communication

Classic Agent Model

Inter-Agent Communication Layers Communication Layers according to Laamanen & Helin

Topological inference

Simple Example of DL notation of ER model AL – representation of an IFC Door Door m BuildingElement * " OverallHeight.PositiveLength * " OverallWidth.PositiveLength

SWRL implementation of Rules fatherOf(?x,?y) ^ brotherOf(?x,?z) -> uncleOf(?z,?y)

SWRL implementation of Rules ENTITY door; SUBTYPE OF (buildingPart) height: REAL; WHERE WR : height > 0; END_ENTITY; door(?x) ^ hasHeight(?x,?height) ^ swrlb:greaterThan(?height, 0) -> WR1(?x,true)

Thank you Jakob Beetz Design Systems group TU/Eindhoven ● Questions, suggestions, comments very welcome

IFC ontology in Protégé

IFC concept structure

Main differences to EXPRESS ● Built-in reasoning capabilities ● Built-in functions for creation and reference of distributed data ● Open world vs. closed world

IFC concept structure ● ISO p28 xml bindings ● EXPRESS (ISO )

Available Taxonomies and Ontologies ● IFC 2.2x (XML Schema) ● Stabu Lexicon (XML Schema) ● eCOGNOS (DAML-OIL) ● WordNet (OWL)

Semantic Web Layers RDF Schema example from Richard Vdovjak