1849443
Ontology Evolution: Not the Same as Schema Evolution
As ontology development becomes a more ubiquitous and collaborative process, ontology versioning and evolution becomes an important area of ontology research. The many similarities between database-schema evolution and ontology evolution will allow us to build on the extensive research in schema evolution. However, there are also important differences between database schemas and ontologies. The differences stem from different usage paradigms, the presence of explicit semantics and different knowledge models. A lot of problems that existed only in theory in database research come to the forefront as practical problems in ontology evolution. These differences have important implications for the development of ontology-evolution frameworks: The traditional distinction between versioning and evolution is not applicable to ontologies. There are several dimensions along which compatibility between versions must be considered. The set of change operations for ontologies is different. We must develop automatic techniques for finding similarities and differences between versions.
17232263
Ontology versioning on the Semantic Web
Ontologies are often seen as basic building blocks for the Semantic Web, as they provide a reusable piece of knowledge about a specific domain. However, those pieces of knowledge are not static, but evolve over time. Domain changes, adaptations to different tasks, or changes in the conceptualization require modifications of the ontology. The evolution of ontologies causes operability problems, which will hamper their effective reuse. A versioning mechanism might help to reduce those problems, as it will make the relations between different revisions of an ontology explicit. This paper will discuss the problem of ontology versioning. Inspired by the work done in database schema versioning and program interface versioning, it will also propose building blocks for the most important aspects of a versioning mechanism, i.e., ontology identification and change specification.
2898750
Ontology Versioning and Change Detection on the Web
To effectively use ontologies on the Web, it is essential that changes in ontologies are managed well. This paper analyzes the topic of ontology versioning in the context of the Web by looking at the characteristics of the version relation between ontologies and at the identification of online ontologies. Then, it describes the design of a web-based system that helps users to manage changes in ontologies. The system helps to keep different versions of web-based ontologies interoperable, by maintaining not only the transformations between ontologies, but also the conceptual relation between concepts in different versions. The system allows ontology engineers to compare versions of ontology and to specify these conceptual relations. For the visualization of differences, it uses an adaptable rule-based mechanism that finds and classifies changes in RDF-based ontologies.
15903228
A Component Framework Based on High-Level Replacement Systems
Abstract This paper is based on two general concepts. The first one is a generic component framework for system modeling presented at FASE 2002, which is especially useful for graph- and net-based modeling techniques. The second one is the concept of high-level replacement systems, which has been studied within the last decade as an abstraction of the DPO-approach for graph transformation systems in a categorical framework, with instantiations to a large class of different modeling techniques. In this contribution both concepts are combined in the sense that the generic transformation concept - essentially used in the component framework - is instantiated by high-level replacement systems. As the main result we show how the properties for transformations required in the component framework can be shown in the case of high-level replacement systems. Moreover, some interesting extensions concerning multiple interfaces, union, and operational semantics of components are proposed.
9604157
Conflict resolution in cooperative design
Design is increasingly becoming a cooperative endeavor carried out by multiple agents with diverse kinds of expertise. The development of tools and underlying theories for supporting cooperative design has lagged, however, behind the growing needs implied by this evolution. 
The goal of this thesis work is to provide a computational model for supporting a critical component of cooperative design; the run-time resolution of conflicts. Though the long-term goal is to support unrestricted conflict resolution among human agents, this thesis focuses on an important subset of this problem: the resolution of domain-level conflicts in routine design, using machine-based agents. 
This thesis proposes a model of conflict resolution in cooperative design that corresponds well to how human design experts actually perform cooperative design, based on analysis of their group problem solving activity. This model supports natural participation for human experts, both at development-time as domain experts asked to create machine-based agents, as well as at run-time as problem solving agents themselves. The conflict resolution model is elaborated into a detailed implemented computational theory that offers many insights into how the conflict resolution expert and design agents should operate. The model incorporates a considerable body of conflict resolution expertise applicable to a wide variety of domains, as well as techniques for acquiring further expertise and evaluating its completeness.
36579462
A component framework for system modeling based on high-level replacement systems
The aim of this paper is to present a generic component framework for system modeling that satisfies main requirements for component-based development in software engineering. In this sense, we have defined a framework that can be used, by providing an adequate instantiation, in connection with a large class of semi-formal and formal modeling techniques. Moreover, the framework is also flexible with respect to the connection of components, providing a compositional semantics of components. This means more precisely that the semantics of a system can be inferred from the semantics of its components. In contrast to other component concepts for data type specification techniques, our component framework is based on a generic notion of transformations. In particular, refinements and transformations are used to express intradependencies, between the export interface and the body of a component, and interdependencies, between the import and the export interfaces of different components. The generic component framework generalizes module concepts for different kinds of Petri nets and graph transformation systems proposed in the literature, and seems to be also suitable for visual modeling techniques, including parts of the UML, if these techniques provide a suitable refinement or transformation concept. In this paper the generic approach is instantiated in two steps. First to high-level replacement systems generalizing the transformation concept of graph transformations. In a second step it is further instantiated to low-level and high-level Petri nets. To show applicability we present sample components from a case study in the domain of production automation as proposed in a priority program of the German Research Council (DFG).
40505356
A Generic Framework for Connector Architectures based on Components and Transformations
The intention of this paper is to extend our generic component framework presented at FASE 2002 [H. Ehrig, F. Orejas, B. Braatz, M. Klein, and M. Piirainen. A generic component concept for system modeling. In Proc. FASE '02, LNCS 2306. Springer, 2002] to a specific kind of connector architectures similar to architectural connections in the sense of Allen and Garlan [ACM Transactions on Software Engineering and Methodology, 1997]. In our generic component framework we have considered components with explicit import, export and body parts connected by embeddings and transformations and composition of components with a compositional transformation semantics. Our framework, however, was restricted to components with a single import and export interface. Here we study architectures based on connectors with multiple imports and components with multiple exports. Architectures studied in this paper are built up from components and connectors in a noncircular way. The semantics of an architecture is defined by reduction step sequences in the sense of graph reductions. The main result shows existence and uniqueness of the semantics of an architecture as a normal form of reduction step sequences. Our generic framework is instantiated on one hand to connector architectures based on CSP as the formal specification technique in the approach by Allen and Garlan. On the other hand it is instantiated to connector architectures based on high-level-replacement systems in general and Petri nets in particular. A running example using Petri nets as modeling technique illustrates all concepts and results.
17480296
Object-Oriented Connector-Component Architectures
This paper presents an important extension of our contribution to FESCA '04, which presented a generic framework for connector architectures. These architectures were defined by components, consisting of a body specification and a set of export interfaces, and connectors, consisting of a body specification and a set of import interfaces plus connecting transformations in both cases. A major restriction of this framework was given by the assumption of non-overlapping connector interfaces. In order to make the generic framework for connector architectures more applicable, it is enriched by the possibility of handling overlapping connector interfaces. Fortunately, it is possible to extend the main results presented at FESCA '04 also to the new framework. Moreover, it is shown that the new framework can be applied to UML class diagrams, state machines and sequence diagrams as heterogeneous specification techniques. The resulting connector framework, including a concept for the composition of components and architectural reduction for UML specifications, is illustrated by a case study concerning the meta data management in Topic Maps.