An ontology-based framework for domain-specific modeling

We are proud to anounce that our work on domain specific language and OWL was published on the Software and Systems Modeling Journal

Domain-specific languages (DSLs) provide abstractions and notations for better understanding and easier modeling of applications in a special domain. Current shortcomings of DSLs include learning curve and formal semantics. This paper reports on a framework that allows the use of ontology technologies to describe and reason on DSLs. The formal semantics of OWL together with reasoning services allows for addressing constraint definition, progressive evaluation, suggestions, and debugging. The approach integrates existing metamodels and concrete syntaxes in a new technical space. A scenario in which domain models for network devices are created illustrates the framework.

More infos on article's page

New Book about MDE with Ontology Technologies

Bridging Technological Spaces. Towards the Combination of Model-Driven Engineering and Ontology Technologies Tobias Walter ISBN 978-3-8325-2936-9 271 Seiten, Erscheinungsjahr: 2011 Preis: 39.50 Eur Stichworte/keywords: Model-driven Engineering, Metamodel Engineering, Semantic Web, Ontology, Technological Space, Description Logics Model-Driven Engineering (MDE) aims to raise the level of abstraction in software system specifications and increase automation in software development. Modelware technological spaces contain the languages and tools for MDE that software developers take into consideration to model systems and domains. Ontoware technological spaces contain ontology languages and technologies to design, query, and reason on knowledge. With the advent of the Semantic Web, ontologies are now being used within the field of software development, as well. In this thesis, bridging technologies are developed to combine two technological spaces in general. In particular, this thesis focuses on the combination of modelware and ontoware technological spaces. Subsequent to a sound comparison of languages and tools in both spaces, the bridging technologies are used to build a common technological space, which allows for the hybrid use of languages and the interoperable use of tools.

TwoUse Toolkit: More than 4000 visits in 11 months.

As we get close to the first anniversary of the TwoUse Toolkit, we take a look at the audience interested in the tool. In the last 11 months, more than 4000 visitors from 81 countries visited our web site. 

Let's keep up the good work!

Templates in OWL Ontologies

Ontology Templates on Prezi

Towards Hybrid Reasoning for Verifying and Validating Multilevel Models

Ontologies and its reasoning services are expected to play an important role in many application domains, as well as in software engineering in general. In model-driven engineering (MDE), models, like UML models, represent and specify software systems.

One problem with using ontologies within software engineering is that while model-driven engineering realizes a four-layer metamodelling architecture, the new version of OWL Web Ontology Language, called OWL 2, it supports only simple metamodelling. Moreover, the semantics of metamodelling in OWL 2 corresponds to the contextual semantics which leads to non-intuitive results. Another issue is that the Open World Assumption (OWA) assumes a model is incomplete. Therefore, we could not validate some constrains in OWA.

We demonstrate multilevel (meta-) modelling using ontologies described in OWL FA, which has a well defined fixed-layered architecture and semantics. As well as an approach to integrate Closed World Assumption (CWA) with OWA in order to use both assumptions for verifying and validating multilevel model.

This joint work with the University of Aberdeen will be presented
at the EKAW conference, October, Lisbon

Specialization and Validation of Statecharts in OWL

It is germane in the engineering process of knowledge bases to represent a model on different abstraction levels, developed and refined by different engineers. Hence, they are initially described at a level of coarse granularity and then refined into a more specific representation.

Given two behavior models like statecharts, it is a challenging task to decide whether one statechart is still a valid specialization of the other, more abstract model. We use OWL to model statecharts and to validate statechart specializations.

This work will be presented at the EKAW conference in October
in Lisbon.

Bridging Software Languages and Ontology Technologies

Today's model-driven development approaches allow for a more productive way of developing software systems. However, building tools and languages for software development still suffer a neglect of semantics in modeling and metamodeling.

An interest to extend software languages that gained scientific and commercial attention is the integration of ontology technology and software development. Ontology formalisms for consistency validation and dynamic classification as well as ontology technologies to enable shared terminologies, automated reasoning, provide means for leveraging metamodeling and language engineering.

Check out our tutorial at SPLASH 2010 (previously OOPSLA) on Bridging Software Languages and Ontology Technologies

Extend Ecore with OWL by Ecore Annotations of OWL Axioms

Do you want more expressiveness than Ecore can offer?

In this video we show how to use an ecore textual language for annotating ecore metamodels with OWL axioms. Afterwards, you can use the OWLizer to transform metamodel and model into OWL.

OWL Annotations for textual Ecore Metamodels

Using the TwoUse Toolkit, it is possible to easily annotate text-based Ecore metamodels by (Ecore-based) textual annotations. The editor provides syntax highlighting for annotations which are based on OWL 2 Web Ontology Language in Manchester Syntax. The Ecore metamodels together with its annotations are transformed by the OWLizer into a pure OWL 2 Ontology (representing the input for reasoning tools). Figure 1 gives a screenshot of the editor which is implemented as an Eclipse plugin based on EMF Text.




In general we have extended a metamodeling language (Ecore) by constructs provided by OWL. Thus we have a much more expressiveness language to develop Ecore-based metamodels which continuously can be used in the MDD process (e.g. to define the abstract syntax of a modeling language or for code generation) and in addition are "ready" for ontology technologies.

The extended grammar for Ecore metamodels and the extended annotations is given in the following:
EPackage =
{EAnnotation} "package" name
[EDataType]
["\"" name "\""] "{" {EClass} {EPackage} "}" ;

EClass =
["abstract"] ("interface" | "class")
["" EClass {"," EClass} ">"] name
["\"" name "\""]
["extends" EClass {"," EClass}]
{classAnnotation} "{" {EClass | EOperation} "}";

EParameter =
{EAnnotation}
{("ordered" | "unique")} EClass name
["(" integer ".." integer ")"] ;

EReference =
{ ("containment" | "derived" | "transient" | "volatile" | "unique" |
"ordered" | "unsettable" | "changeable" | "resolveProxies") }
{frontReferenceAnnotation}
"reference" (EClass | EGenericType) name
["=" "\"" name "\""]
["(" integer ".." integer ")"]
["opposite" EReference] {endReferenceAnnotation} ";" ;

EOperation =
{EAnnotation}
{("ordered" | "unique")} "operation" ("void" | EClass)
["(" integer ".." integer ")"]
["" ETypeParameter {"," ETypeParameter} ">"] name "(" [EParameter {"," EParameter}] ")"
["throws" EClass {"," EClass}] ";" ;

EEnumLiteral = {EAnnotation} EDataType ":" name "=" "\"" EEnumLiteral "\"" ";" ;
EAnnotation = "[" {
"eAnnotations" ":" EAnnotation |
"source" ":" "\"" name "\"" |
"details" ":" "\"" name "\"" "=" "\"" name "\"" |
"contents" ":" EObject |
"references" ":" EReference |
"eModelElement" ":" EObject } "]";
EObject = "EObject";
EDataType = {EAnnotation} ["serializable"] "datatype" name "\"" name "\"";
ETypeParameter = {EAnnotation} name ;
EGenericType =
"typed" ["" (ETypeParameter | "?" "extends" EGenericType | "?" "super" EGenericType) ">"]
EClass ["" (EGenericType | "?" ) {"," (EGenericType | "?")} ">"] ;



frontReferenceAnnotation = "(" (
"functional" |
"inversefunctional" |
"symmetric" |
"asymmetric" |
"reflexive" |
"irreflexive" |
"transitive"
) ")";

endReferenceAnnotation = "(" (
"equivalentTo" OPE |
"subPropertyOf" OPE |
"domain" CE |
"range" CE |
"disjointWith" OPE |
"inverseOf" name |
"subPropertyChain" OPE "o" OPE {"o" OPE}
) ")";

classAnnotation = "(" (
("equivalentTo" | "disjointWith") CE {CE} |
"subClassOf" CE |
"disjointUnionOf" CE CE {CE}
) ")";

CE = "(" (
["not"] name |
"not" CE |
CE "and" CE { "and" CE } |
CE "or" CE {"or" CE} |
OPE ("some" | "only") CE |
OPE "Self" |
OPE ("min" | "max" | "exactly") "cardinality" nonnegativeinteger CE
) ")" ;

OPE = name | "(" "inverse" name ")" ;

digit = "0"|"1"|"2"|"3"|"4"|"5"|"6"|"7"|"8"|"9";
nonnulldigit = "1"|"2"|"3"|"4"|"5"|"6"|"7"|"8"|"9";
integer = ["-"] nonnulldigit {digit} | "0";
nonnegativeinteger = "0" | nonnulldigit {digit};
name = ( letter | "_" ) { letter | digit | "_" } ;
letter = "a".."z" | "A".."Z" ;

OWL, UML, SPARQL, templates: TwoUse examples

This video shows how to start using the twouse toolkit by examples:

• SPARQL Querying
• OWL Ontology Template
• OWL Graphical Notation
• OWL Functional Syntax
• SWRL Rule Graphical Notation
• SWRL Rule with UML Profile for SWRL
• SPARQLAS Query
• OWL Ontology with UML Profile for OWL

OWL + Metamodel: Model Bridge

Model bridges connect software models and ontologies on the modeling layer M1. They are de fined in the metamodeling layer M2 between diff erent metamodels. The figure below exemplifies a model bridge.

Model Bridge

Integration bridges merge information of the models from the software modeling and from the ontology space. This allows the building of integrated models (on modeling layer M1) using constructs of both modeling languages in a combined way, e.g. to integrate UML class diagrams and OWL.

A transformation bridge describes a (physical) transformation between models in layer M1. The models are kept separately in both modeling spaces. The information is moved from one model to the model in the other modeling space according to the transformation bridge.

OWL + Ecore: Language Bridges

The figure below depicts the general architecture of a language bridge, combining software languages and ontology technologies. The bridge itself is de fined at the M3 layer, where a metametamodel like Ecore is considered and bridged with the OWL metamodel. Here we diff er between two kinds of bridges: M3 Integration Bridge and M3 Transformation Bridge.

Language Bridge

The design of an M3 integration bridge consists mainly of identifying concepts in the Ecore metametamodel and the OWL metamodel which are combined.

The M3 Transformation Bridge allows language designers and language users to achieve representations of software languages (Metamodel/Model) in OWL. It provides the transformation of software language constructs like classes and properties into corresponding OWL constructs.

Using Templates in OWL Ontologies

Integrating model-driven development and semantic web resulted in metamodels
and model-driven tools for the semantic web. However, these metamodels or tools
do not provide dedicated support for dealing with templates in ontology
engineering.

Using Templates with OWL and UML Notation

Templates are useful for encapsulating knowledge and modeling
recurrent sets of axioms like ontology design patterns. We propose an extension
of existing metamodels and tools to support ontology engineers in modeling
OWL ontology templates. Our approach allows ontology engineers to keep template
specifications as first-class citizens, reducing complexity and increasing
reusability in ontology engineering.

Bridging Software Languages and Ontology Technologies: Tutorial at SPLASH 2010

Current model-driven development approaches allow for a more productive way of developing software systems. However, building tools and languages for software development still suffer a neglect of semantics in modeling and metamodeling.

An interest to strengthen semantics in modeling and metamodeling that gained scientific and commercial attention is the integration of ontology technology and software development. Ontology formalisms for consistency validation and dynamic classification as well as semantic web technologies for enabling shared terminologies and automated reasoning provide means for leveraging metamodeling and language engineering.

This tutorial on Bridging Software Languages and Ontology Technologies  at SPLASH 2010 enlightens the potential of ontology and semantic web technology for modeling and metamodeling in software development, positioning it among modeling standards like UML, and MOF; and (2) illustrates ontology-enabled software development with real application scenarios in areas like software design patterns, domain-specific languages and variability management.

Model Driven Engineering with Ontology Technologies

Ontologies constitute formal models of some aspect of the world that may be used for drawing interesting logical conclusions even for large models. Software models capture relevant characteristics of a software artifact to be developed, yet, most often these software models have no formal semantics, or the underlying (often graphical) software language varies from case to case in a way that makes it hard if not impossible to fix its semantics.

At the Reasoning Web Summer School 2010: Semantic Technologies for Software Engineering we present a lecture on the use of ontology technologies for software modeling in order to carry over advantages from ontology technologies to the software modeling domain. It will turn out that ontology-based metamodels constitute a core means for exploiting expressive ontology reasoning in the software modeling domain while remaining flexible enough to accommodate varying needs of software modelers.

Ecore Models | Metamodels -> OWL Ontologies = OWLizer

We show how to use TwoUse's OWLizer to transform Ecore Models and Metamodels into OWL ontologies. In this example, the UML class diagram model elements are transformed into OWL individuals of the UML ontology and the UML metamodel classes are transformed into OWL classes.

UML + OWL Ontology and SPARQL

This demo of the TwoUse Toolkit shows UML class diagram, OWL ontology and SPARQL to dynamically classify instances at runtime. We model the variations of the class SalesOrder with the web ontology language, namely USSalesOrder and GermanSalesOrder. Later, we write a query operation that asks for the most specific type of the contextual object.

BPMN process model -> OWL ontology = Validating Process Refinements

"A crucial task in business process management is the validation of business process refinements. A business process refinement is a process description in a more fine-grained representation. The refinement is either with respect to an abstract model or with respect to component's principle behavior model. This video shows a process refinement based on the execution set semantics. Predecessor and successor relations of the activities are described in an OWL ontology in which the refinement is represented and validated by concept satisfiability checking."

More information on this paper

OWL ontology with UML Class Diagram Profile for OWL

How to create a simple OWL ontology using the OMG UML Profile for OWL with the TwoUse Toolkit.

Improving Software Design Patterns with UML, OWL and SPARQL

We deal with problems in common design patterns and proposes OWL to remedy these issues. We exploit the TwoUse approach, which integrates OWL and UML class diagrams to overcome drawbacks of the Strategy Pattern, that are also extensible to the Abstract Factory Pattern.