On incremental global update support in cooperative database systems

OzGateway is a cooperative database system designed for integrating heterogeneous existing information systems into an interoperable environment. It also aims to provide a gatewway for legacy information system migration. This paper summarises the problems and results of multidatabase transaction management research. In supporting global updates in OzGateway in an evolutionary way, we introduce a classification of multidatabase transactions and discuss the problems in each category. The architecture of OzGateway and the design of the global transaction manager and servers are presented

A Framework for Data Sharing in Computer Supported Cooperative Environments

Concurrency control is an indispensable part of any information sharing system. Co-operative work introduces new requirements for concurrency control which cannot be met using existing applications and database management systems developed for non-cooperative environments. The emphasis of concurrency control in conventional database management systems is to keep users and their applications from inadvertently corrupting data rather than support a workgroup develop a product together. This insular approach is necessary because applications that access the database have been built with the assumptions that they have exclusive access to the data they manipulate and that users of these applications are generally oblivious of one another. These assumptions, however, are counter to the premise of cooperative work in which human-human interaction is emphasized among a group of users utilizing multiple applications to jointly accomplish a common goal. Consequently, applying conventional approaches to concurrency control are not only inappropriate for cooperative data sharing but can actually hinder group work. Computer support for cooperative work must therefore adopt a fresh approach to concurrency control which does promote group work as much as possible, but without sacrifice of all ability to guarantee system consistency. This research presents a new framework to support data sharing in computer supported cooperative environments; in particular, product development environments where computer support for cooperation among distributed and diverse product developers is essential to boost productivity. The framework is based on an extensible object-oriented data model, where data are represented as a collection of interrelated objects with ancillary attributes used to facilitate cooperation. The framework offers a flexible model of concurrency control, and provides support for various levels of cooperation among product developers and their applications. In addition, the framework enhances group activity by providing the functionality to implement user mediated consistency and to track the progress of group work. In this dissertation, we present the architecture of the framework; we describe the components of the architecture, their operation, and how they interact together to support cooperative data sharing

EIES 2 : a distributed architecture for supporting group work

The Computerized Conferencing Center (CCCC) at New Jersey Institute of Technology (NJIT) has been researching on-line group communications for 17 years by developing and studying tools to advance the collective intelligence . The Electronic Information Exchange System 2 (EIES2) provides a research, development and operational environment for distributed computer supported cooperative work (CSCW) systems. The EIES 2 distributed Smalltalk processor provides for rapid prototyping and implementation of muti-media CSCW facilities in the network environment. The Smalltalk support of the object model, and meta-language properties make it ideally suited for incremental development CSCW applications. The EIES2 communication environment supports a decentralized network architecture. Modern standards are used in the implementation of data structures, communication interfaces and database. The EIES2 application layer protocols support use ASN.1 data representation to access to an object-oriented distributed database via X.ROS remote operation services. EIES2 can serve as a foundation on which group work systems may be built and defines protocols that can allow them to inter-operate. An initial system presents a powerful metaphor of conferences and activities which provides an extensible framework upon which to add group work applications. Work to date has provided structures for information exchange, inquiry networking, information filtering, the on-line virtual classroom, and group decision support. This paper presents the system architecture model used for EIES2 and describes the implementation and current applications

Validation of Framework Code Approach to a Life Prediction System for Fiber Reinforced Composites

The grant was conducted by the MMC Life Prediction Cooperative, an industry/government collaborative team, Ohio Aerospace Institute (OAI) acted as the prime contractor on behalf of the Cooperative for this grant effort. See Figure I for the organization and responsibilities of team members. The technical effort was conducted during the period August 7, 1995 to June 30, 1996 in cooperation with Erwin Zaretsky, the LERC Program Monitor. Phil Gravett of Pratt & Whitney was the principal technical investigator. Table I documents all meeting-related coordination memos during this period. The effort under this grant was closely coordinated with an existing USAF sponsored program focused on putting into practice a life prediction system for turbine engine components made of metal matrix composites (MMC). The overall architecture of the NMC life prediction system was defined in the USAF sponsored program (prior to this grant). The efforts of this grant were focussed on implementing and tailoring of the life prediction system, the framework code within it and the damage modules within it to meet the specific requirements of the Cooperative. T'he tailoring of the life prediction system provides the basis for pervasive and continued use of this capability by the industry/government cooperative. The outputs of this grant are: 1. Definition of the framework code to analysis modules interfaces, 2. Definition of the interface between the materials database and the finite element model, and 3. Definition of the integration of the framework code into an FEM design tool

Schema architecture and their relationships to transaction processing in distributed database systems

We discuss the different types of schema architectures which could be supported by distributed database systems, making a clear distinction between logical, physical, and federated distribution. We elaborate on the additional mapping information required in architecture based on logical distribution in order to support retrieval as well as update operations. We illustrate the problems in schema integration and data integration in multidatabase systems and discuss their impact on query processing. Finally, we discuss different issues relevant to the cooperation (or noncooperation) of local database systems in a heterogeneous multidatabase system and their relationship to the schema architecture and transaction processing

An electronic health record to support patients and institutions of the health care system

The department of Medical Informatics of the University Hospital Münster and the Gesakon GmbH (an university offspring) initiated the cooperative development of an electronic health record (EHR) called "akteonline.de" in 2000. From 2001 onwards several clinics of the university hospital have already offered this EHR (within pilot projects) as an additional service to selected subsets of their patients. Based on the experiences of those pilot projects the system architecture and the basic data model underwent several evolutionary enhancements, e.g. implementations of electronic interfaces to other clinical systems (considering for example data interchange methods like the Clinical Document Architecture - standardized within the HL7 group - and also interfacing architectures of German GP systems, such as VCS and D2D). "akteonline.de" in its current structure supports patients as well as health care professionals and aims at providing a collaborative health information system which perfectly supports the clinical workflow even across institutional boundaries and including the patient himself. Since such an EHR needs to strictly fulfill high data security and data protection requirements, a complex authorization and access control component has been included. Furthermore the EHR data are encrypted within the database itself and during their transfer across the internet

Design of a service-oriented architecture for federated systems

A Federated System is a collection of independent, cooperative, possibly heterogeneous and autonomous computer systems (usually database systems) which allows sharing all or some of its data. A Service-Oriented Architecture is an application architecture whose functionalities are defined as independent services which offer transparent communication between physically distributed components, possibly heterogeneous and autonomous. In this context, it is interesting to analyze how a Federated System can be designed within the ideas proposed by Service-Oriented Architectures. This paper presents the design of a Service-Oriented Architecture for Federated Systems. The architecture supports many users sharing data; access control to the data based on access rights which generates many views from a data source, as well as allowing a high automation level for the integration and querying processes. In addition, the bases of a federation's management framework are defined. This framework, as well as the architecture, is validated through an evolutionary prototype towards a completely functional implementation.Facultad de Informátic

PACMAS: A Personalized, Adaptive, and Cooperative MultiAgent System Architecture

In this paper, a generic architecture, designed to support the implementation of applications aimed at managing information among different and heterogeneous sources, is presented. Information is filtered and organized according to personal interests explicitly stated by the user. User pro- files are improved and refined throughout time by suitable adaptation techniques. The overall architecture has been called PACMAS, being a support for implementing Personalized, Adaptive, and Cooperative MultiAgent Systems. PACMAS agents are autonomous and flexible, and can be made personal, adaptive and cooperative, depending on the given application. The peculiarities of the architecture are highlighted by illustrating three relevant case studies focused on giving a support to undergraduate and graduate students, on predicting protein secondary structure, and on classifying newspaper articles, respectively