6836947
Deductive verification of stabilizing systems
33236770
Formal Verification of Stabilizing Systems
This paper links too formerly rather disjoint areas: formal verification and stabilization. Stabilization is a vitally emerging paradigm in fault tolerant distributed computing; formal verification investigates mathematically rigorous techniques to reason about systems.
17738680
Hierarchical Automata as Model for Statecharts
Statecharts are a very rich graphical specification formalism supported by the commercial tool Statemate. Statecharts comprises powerful concepts such as interlevel transitions, multiple-source/multiple-target transitions, priority amongst transitions and simultaneous execution of maximal non-conflicting sets of transitions. Every add-on tool which is supposed to be linked with the Statemate tool have to deal with the rather involved semantics of these concepts. We propose extended hierarchical automata as an intermediate format to facilitate the linking of new tools to the Statemate environment, whose main idea is to devise a simple formalism with a more restricted syntax than statecharts which nevertheless allows to capture the richer formalism. We define the format, give operational semantics to it, and translate statecharts to it.
562314
The Context Interchange mediator prototype
The <italic>Context Interchange</italic> strategy presents a novel approach for mediated data access in which semantic conflicts among heterogeneous systems are not identified a priori, but are detected and reconciled by a <italic>context mediator</italic> through comparison of <italic>contexts</italic>. This paper reports on the implementation of a Context Interchange Prototype which provides a concrete demonstration of the features and benefits of this integration strategy.
26524606
Automatic Rule Derivation For Semantic Query Optimization
62729675
The Composite Information System Laboratory (CISL) Project at MIT
The Composite Information Systems Laboratory (CISL) at MIT is involved in research on the strategic, organizational and technical aspects of the integration of multiple heterogeneous database systems. In this paper we examine the scope of the work being done at CISL. Certain research efforts in the technical areas of system integration are emphasized; in particular semantic aspects of the integration process and methods for tracking data sources in composite information systems.
41563606
Conceptualizing Semantic Interoperability: A Perspective From the Knowledge Level
Currently, there is a proliferation of database integration approaches in response to the need to achieve semantic interoperability in heterogeneous, distributed and autonomous environments. To date, however, we lack abstract, formal descriptions of the task of semantic interoperation, independent of idiosyncratic implementation details. Such abstract descriptions are needed to aid our understanding of these various complex systems that are being constructed. Therefore, we argue that a knowledge level perspective of interoperable systems is desirable. The knowledge level serves as an abstract specification of what a system should do and facilitates the design and analysis of complex systems. In this paper, we show how an interoperable system, based on the Context Interchange Architecture, may be specified in terms of first-order logic which is an ideal specification language at the knowledge level. This specification represents a theoretical ideal which serves to formalize and communicate the key ideas behind the Context Interchange Approach, unencumbered by the details, limitations and compromises of specific implementations. As such, it provides a rigorous basis for implementing such systems. Similar specifications may also be developed for other models of interoperable systems. As a result, we have a rigorous means of understanding, comparing and analyzing these complex systems.
14329450
Semantic interoperability in the securities industry: context interchange mediation of semantic differences in enumerated data types
Using securities industry examples, the context interchange mediation knowledge architecture is applied to interoperability problems for enumerated data types, such as codes and other symbols used to represent conceptual distinctions. Ongoing efforts in the securities industry to develop new XML-based standards for information interchange are examined. Using components representing similar securities information, drawn from different but complementary securities standards and sources, example problems of information interoperability are examined. We show that transforming data representation into an autonomously specified context model and thence into a general domain ontology allows successful interoperability in several ways depending on how each context is explained to the mediator.