Showing papers on "Semantic interoperability published in 1995"

Semantic interoperability

Abstract: Interoperability among components of large-scale, distributed systems is the ability to exchange services and data with one another. It is based on agreements between requesters and providers on, for example, message passing protocols, procedure names, error codes, and argument types. Semantic interoperability ensures that these exchanges make sense—that the requester and the provider have a common understanding of the “meanings” of the requested services and data. For example, an application that requests customer data must agree on what a “customer” is, with the application that provides it. Semantic interoperability is based on agreements on, for example, algorithms for computing requested values, the expected side effects of a requested procedure, or the source or accuracy of requested data elements. The purposes of this note are to indicate why semantic interoperability is so hard to achieve, and to suggest that commerical repository technology can provide the beginnings of help to make it easier. Semantic agreements are often lacking when old data or procedures are used for new purposes not anticipated by their original developers. This is because the semantics of procedures and data are rarely explicit, so requesters cannot determine whether their assumptions are matched by providers. The results of such mismatches can be catastrophic—wrong results, sometimes with no indication that they are wrong. For example, the DoD attempted to use their database of personnel addresses to determine where veterans were likely to seek medical care (in order to plan for building veterans’ hospitals); only later did they discover that, because the addresses were originally collected to track active personnel, they included temporary assignments (which were useless and even misleading for the new purpose) [Edmonds 1994]. Semantic agreements may also be lacking among new systems that are the products of independent development efforts. Semantic agreements require the involvement of people (users, designers, and developers) who intuitively associate semantics with data and procedure names, type definitions and type hierarchies, screen layouts, and report formats (titles, column and row headings, dates, units of measure, sort order, footnotes, etc.). Other semantic information is implicit in application code, in text and diagrams, and in the local “oral tradition.” Making semantics explicit in metadata would allow people to detect mismatched assumptions and to create required mappings to overcome them. However, making the necessary semantic information explicit can be extraordinarily difficult, for several reasons:

A classification of semantic conflicts in heterogeneous database systems

Abstract: Increasingly companies are doing business in an environment replete with heterogeneous information systems which must cooperate. Cooperation between these systems presupposes the resolution of the semantic conflicts that are bound to occur. In this article, we propose a classification of semantic conflicts which can be used as the basis for the incremental discovery and resolution of these conflicts. We classify conflicts along the two dimensions of naming and abstraction which, taken together, capture the semantic mapping of the conflict. We add a third dimension, level of heterogeneity to assist in the schematic mapping between two databases. The classification provides a systematic representation of alternative semantic interpretations of conflicts during the reconciliation process. As a result, the design of query‐directed dynamic reconciliation systems is possible. The classification is shown to be sound and minimal. Completeness is discussed.

A Fundamental Framework for Realizing Semantic Interoperability in a Multidatabase

Abstract: In multidatabase research, the realization of semantic interoperability is the most im­ portant issue for resolving semantic heterogeneity between different databases. In this paper, we propose a fundamental framework for realizing semantic interoperability at the level of semantic relationships between data items in a multi database environment. We present a metadatabase system which extracts the significant information from dif­ ferent databases. The metadatabase system uses a mathematical model of meaning to dynamically recognize the semantic equivalence, similarity, and difference between data items. The essential feature of this model is that the specific meaning of a data item is dynamically fixed and unambiguously recognized according to the context by semantic interpretation mechanisms. © 1995 John Wiley & Sons, Inc.

A fundamental framework for realizing semantic interoperability in a multidatabase environment

Abstract: In multidatabase research, the realization of semantic interoperability is the most important issue for resolving semantic heterogeneity between different databases. In this paper, we propose a fundamental framework for realizing semantic interoperability at the level of semantic relationships between data items in a multi database environment. We present a metadatabase system which extracts the significant information from different databases. The metadatabase system uses a mathematical model of meaning to dynamically recognize the semantic equivalence, similarity, and difference between data items. The essential feature of this model is that the specific meaning of a data item is dynamically fixed and unambiguously recognized according to the context by semantic interpretation mechanisms. © 1995 John Wiley & Sons, Inc.

Interoperability in information systems

Abstract: . Two operationally autonomous information systems intemperate it system can make use of information contained in the other, or if they exchange transactions. A widely held assumption in this field is that the development interoperability among information systems should preserve the design autumn of the individual information systems in a strong sense. This paper demonstrate that preservation of strong design autonomy is not always possible owing to necessity to resolve semantic hereogeneity among the systems. This neces violation of autonomy calls into question the utility of research on general a tectures and the possibility of general solutions. We suggest some theme certain special cases where we believe feasible and useful computer scie research can be done in this area, and also suggest some implications for standard models of architectures for federated databases. Copyright

Interoperability issues in large-scale distributed object systems

Abstract: Issues of interoperability are receiving increasing attention as organizations move from mainframe-based “islands of automation” toward open, distributed computing environments, and as national efforts toward an “information superhighway” receive increasing attention. The demand for interoperability is driven by the accelerated construction of large-scale distributed systems for operational use. The Internet (particularly its commercial and research applications) is one such system, and much has been and is being written about it. However, in this paper we focus on enterprise-wide client/server systems being developed to support operational computing within large organizations to illustrate interoperability issues (Figure 1). Requirements for these systems are not speculative; numerous large businesses are building systems of this type today. The architecture is distributed, and divided into three logical layers: applications, shared services, and data. The layers are only logical groupings; all components communicate via a common object-oriented messaging backplane. This reflects the increasing agreement that modeling a system as a distributed collection of objects provides the appropriate framework for integrating resources in these environments, and is illustrated by the number of standards activities that are moving toward adopting, or have already adopted, an objectoriented approach. System operations are based on explicit business rules representing business process definitions. The architecture supports integrated management of objects representing both business abstractions (customers, products), and elements of the enterprise and computing infrastructure (network elements, software, plant facilities). Applications are constructed from reusable components and users interact with the system via compound document and graphical interfaces (in many implementations, the “applications” layer is really just the graphical interface to the applications, with the application logic itself in the middle layer, integrated with or controlled by the business rules). Such architectures require interoperability at many different levels, including the physical level (e.g., agreed-on data representations), and the object-model level (e.g., agreements on object interface characteristics), Much discussion of interoperability involves these levels. However, there are also requirements for interoperability at higher levels of abstraction. For example, there is a need for more complex agreements among object classes, such as those defining cooperation among the sets of object classes found in object frameworks [Gamma et al. 1995]. Interoperability requirements ultimately reach the level of semantic interoperability (agreements on meaning ). For example, design of large-scale business systems are increasingly based on definitions of business objects, which attempt to reflect organization-wide agreements on the meanings of key busi-

Interoperation of object-oriented applications

Abstract: One of the important advantages of the object-oriented design and development methodology is the ability to reuse existing software modules However the introduction of many programming languages with different syntax, semantics and/or paradigms has created the need for a consistent inter-language interoperability support framework We present a brief overview of the most characteristic interoperability support methods and frameworks allowing the access and reuse of objects from different programming environments and focus on the interface bridging object-oriented interoperability support approach

Semantic Integration of Conceptual Schemes.

Abstract: Abstract Our goal is to work out an integration process which makes it possible to give a global design schema obtained from several schemas, each of them describing the same reality viewed in different ways, in order to obtain the fullest view. Problems and conflicts arise during the schema integration. They are due to the several ways of representing the semantic knowledge and of structuring knowledge (using the same design model). When the detection and solution of structural problems are model dependent, the detection and solution of semantic problems are not model dependent. To represent the semantic of the words which are used in a schema, we have defined a model of a thesaurus drawn from the domain dealing with the meaning of words: linguistics. In this paper, we will show the interest in using this fuzzy thesaurus when design schema are being integrated.

Interoperability of Distributed Platforms: a Compatibility Perspective

Abstract: Interoperability of heterogeneous distributed platforms is affected by differences in their type systems, including both differences in syntax and semantics of types and approaches to inclusion polymorphism. This paper examines the differences of well known distributed platforms (DOE, ANSAware, CORBA) as well as models for distributed and object oriented systems. The examination is illustrated by a scenario of their cooperation. The scenario is based on resolving differences during the federation process. The federation involves extension of persistent type repositories for each domain to incorporate mappings among domains. The scenario focuses on differences in compatibility relationships.

Description, Conversion, and Planning For Semantic Interoperability

Abstract: The issue of semantic interoperability pervades distributed systems whose components are designed independently. For example, when a source intends 70 to mean “70 meters, with 20% error”, the receiver must not interpret the result as “70 feet, exactly”. We examine semantic interoperability problems in a distributed object management environment, i.e., for a system of distributed objects and services rather than for a database. A semantic interoperability service is defined, and its required functional components — argument describers, conversion functions, and a planner — are identified. We categorize levels of service that each component may provide, and how these choices affect system functionality and evolution. We also begin to examine the various ways to map the functional architectures to software components — sources, receivers, mediators, and request broker — and data administration tasks. Finally, we contrast with semantic interoperability for database clients, and discuss why the type system should not be the repository for conversion knowledge.

TeamBox: an exploration of collaborative interoperability

Abstract: Given that teams will tend to use a combination of generic groupware and individual applications, there is a need to address issues of interoperability. However, traditional system interoperability that focuses on making data and applications more accessible may not suffice. In collaborative work, the creating and acting on knowledge is inter-related. Collaborative interoperability should support the sharing and coordination of the knowledge represented by the relationships and context of the data. The requirements and dimensions of collaborative interoperability are outlined. The concept of a “collaborative transaction” is proposed as a knowledge representation and coordination scheme. The TeamBox design architecture is introduced. The feasibility of the architecture is illustrated by the description of a working prototype.

Towards Schema Queries for Semantic Data Models.

Abstract: We contribute to metadata management by giving a speciication of extended Entity-Relationship schemas with the extended Entity-Relationship model itself. We formulate a number of integrity constraints describing the context-sensitive requirements an extended Entity-Relationship schema has to ful-ll. By doing this, a certain class of schema queries can be formulated.

Issues in incorporation semantic integrity in molecular biological object-oriented databases

Abstract: Issues critical to ensuring semantic integrity in molecular biological data collections have been identified and include complexity, exceptions, missing data, changing models, holism and integration, delocalized data, interoperability and nomenclature. This combination is peculiar to biology and presents some interesting problems as a result. Little is known about semantic checking in object-oriented databases in general, but because such technology appears highly suitable for modeling biological data, it is appropriate to examine the ways in which object-oriented technology can support this functionality. It is concluded that object-oriented technology will support semantic checking even in a complex domain like biology. We propose 10 guidelines for future work including ways of treating exceptional cases and 'positioning' of constraints in a schema.

An object-oriented approach to the semantic interpretation of medical text

Abstract: A primary problem in the area of text understanding is semantic analysis. This involves both formalizing the general and domain-dependent semantic information relevant to the task involved, and providing an appropriate mapping between the syntactic constituents of a parsed sentence and the semantic representation of the sentence based on the semantic information. This study introduces an object-oriented approach to semantic interpetation that integrates the semantic processing into syntactic structures. The semantic interpreter has two components. The first is a syntactic decomposer. It takes the syntactic description for a sentence as its input, mapping the syntactic structure into an object tree. The other is a semantic merger. It starts from lexical items and merges the semantic frames attached to the objects of syntactic components recursively until a semantic frame net for the sentence is produced. A frame language is designed to formalize the semantic information into semantic frames. This semantic interpreter has been integrated with an automatic knowledge acquisition system that builds the knowledge base for expert systems from medical text. The source of the text was medical diagnosis for heart diseases by ECG. The system is implemented in an object-oriented programming (C + + ). Some results of the application are presented and discussed.

Integrating Schemas Of HeterogeneousDatabase Systems

Abstract: Keywords: interoperability Note: poster Reference LBD-CONF-1995-003 Record created on 2007-01-16, modified on 2016-08-08

Persistent Object Systems and Interoperability: Linguistic and Architectural Requirements

Abstract: An important aspect of currently developed persistent object systems is support for interoperability with other systems. A central issue in supporting interoperability is achieving type compatibility. We argue that abstraction is also a key interoperability issue. The level of abstraction depends on such features as modularity, encapsulation, orthogonality, minimality, clean and precise semantics, universality, extensibility, type safety and genericity, and others. In the paper we discuss these concepts and some architectures of gateways.