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The Semantic Application Design Language (SADL) combines advances in standardized declarative modeling languages based on formal logic with advances in domain-specific language (DSL) development environments to create a controlled-English language that translates directly into the Web Ontology Language (OWL), the SPARQL graph query language, and a compatible if/then rule language. Models in the SADL language can be authored, tested, and maintained in an Eclipse-based integrated development environment (IDE). This environment offers semantic highlighting, statement completion, expression templates, hyperlinking of concepts to their definition, model validation, automatic error correction, and other advanced authoring features to enhance the ease and productivity of the modeling environment. In addition, the SADL language offers the ability to build in validation tests and test suites that can be used for regression testing. Through common Eclipse functionality, the models can be easily placed under source code control, versioned, and managed throughout the life of the model. Differences between versions can be compared side-by-side. Finally, the SADL-IDE offers an explanation capability that is useful in understanding what was inferred by the reasoner/rule engine and why those conclusions were reached. Perhaps more importantly, explanation is available of why an expected inference failed to occur. The objective of the language and the IDE is to enable domain experts to play a more active and productive role in capturing their knowledge and making it available as computable artifacts useful for automation where appropriate and for decision support systems in applications that benefit from a collaborative human-computer approach. SADL is built entirely on open source code and most of SADL is itself released to open source. This paper explores the concepts behind the language and provides details and examples of the authoring and model lifecycle support facilities.

Ontology authoring is a complex process, where commonly the automated reasoner is invoked for verification of newly introduced changes, therewith amounting to a time-consuming test-last approach. Test-Driven Development (TDD) for ontology authoring is a recent test-first approach that aims to reduce authoring time and increase authoring efficiency. Current TDD testing falls short on coverage of OWL features and possible test outcomes, the rigorous foundation thereof, and evaluations to ascertain its effectiveness. We aim to address these issues in one instantiation of TDD for ontology authoring. We first propose a succinct, logic-based specification of TDD testing and present novel TDD algorithms so as to cover also any OWL 2 class expression for the TBox and for the principal ABox assertions, and prove their correctness. The algorithms use methods from the OWL API directly such that reclassification is not necessary for test execution, therewith reducing ontology authoring time. The algorithms were implemented in TDDonto2, a Protégé plugin. TDDonto2 was evaluated by users, which demonstrated that modellers make significantly fewer errors with TDDonto2 compared to the standard Protégé interface and complete their tasks better using less time. Thus, the results indicate that TDD is a promising approach in an ontology development methodology.

Despite the many integration tools proposed for mapping between OWL ontologies and the object-oriented paradigm, developers are still reluctant to incorporate ontologies into their code repositories. In this paper we survey existing approaches for OWL-to-OOP mapping trying to identify reasons for this shy adoption of ontologies among conventional software developers. We present a classification of the surveyed approaches and tools based on their technical characteristics and their resulting artifacts. We discuss further potential reasons beyond what have been addressed in the literature before finally providing our own reflection and outlook.

Distributed Identity Management (DIM) refers to the ability of defining distributed identities of agents and roles, i.e. a single agent is represented using multiple unique identifiers managed in different namespaces and may have various roles across those namespaces. We propose semDIM, a novel approach for Semantic DIM based on a Semantic Web architecture. For the first time, semDIM provides a framework for a distributed definition and management of entities such as persons being part of an organization, groups, and roles across namespaces. It is suitable for informal, i.e. social networks, as well as for professional networks such as cross-organizational collaborations. In addition, the framework ensures authenticity, authorization and integrity for such distributed identities by featuring certificate-based graph signatures. Beyond the capabilities of existing Identity Management solutions, we allow distributed identifiers and management of groups (consisting of agents and sub-groups) and roles as “first-class entities”. semDIM uses owl:sameAs relations to represent and verify distributed identities via formal reasoning. This concept enables novel functionalities for DIM, as these entities can be identified, related to one another, as well as be managed across namespaces. Our semDIM approach consists of a modular software architecture, a process model using a novel approach for pattern-based concurrency control, as well as a set of state-of-the-art formal OWL ontology patterns. The use of formal patterns ensures semantic interoperability, and extensibility for future requirements. Thereby, our approach can be combined with other applications based on the same or related patterns. We evaluate semDIM in the context of a real-world scenario of securely exchanging DIM information across organizations.