19 research outputs found

    Evolving information systems: meeting the ever-changing environment

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    To meet the demands of organizations and their ever-changing environment, information systems are required which are able to evolve to the same extent as organizations do. Such a system has to support changes in all time-and application-dependent aspects. In this paper, requirements and a conceptual framework for evolving information systems are presented. This framework includes an architecture for such systems and a revision of the traditional notion of update. Based on this evolutionary notion of update (recording, correction and forgetting) a state transition-oriented model on three levels of abstraction (event level, recording level, correction level) is introduced. Examples are provided to illustrate the conceptual framework for evolving information systems

    Solar Influence on Nuclear Decay Rates: Constraints from the MESSENGER Mission

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    We have analyzed Cs-137 decay data, obtained from a small sample onboard the MESSENGER spacecraft en route to Mercury, with the aim of setting limits on a possible correlation between nuclear decay rates and solar activity. Such a correlation has been suggested recently on the basis of data from Mn-54 decay during the solar flare of 13 December 2006, and by indications of an annual and other periodic variations in the decay rates of Si-32, Cl-36, and Ra-226. Data from five measurements of the Cs-137 count rate over a period of approximately 5.4 years have been fit to a formula which accounts for the usual exponential decrease in count rate over time, along with the addition of a theoretical solar contribution varying with MESSENGER-Sun separation. The indication of solar influence is then characterized by a non-zero value of the calculated parameter \xi, and we find \xi=(2.8+/-8.1)x10^{-3} for Cs-137. A simulation of the increased data that can hypothetically be expected following Mercury orbit insertion on 18 March 2011 suggests that the anticipated improvement in the determination of \xi could reveal a non-zero value of \xi if present at a level consistent with other data.Comment: Accepted for publication in Astrophysics and Space Science, 2011. 7 pages, 5 figures. Version 2 has corrected Figure 1, since Fig. 1 did not appear correctly in Version

    Evolving information systems: meeting the everā€changing environment

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    Abstract. To meet the demands of organizations and their everā€changing environment, information systems are required which are able to evolve to the same extent as organizations do. Such a system has to support changes in all timeā€and applicationā€dependent aspects. In this paper, requirements and a conceptual framework for evolving information systems are presented. This framework includes an architecture for such systems and a revision of the traditional notion of update. Based on this evolutionary notion of update (recording, correction and forgetting) a state transitionā€oriented model on three levels of abstraction (event level, recording level, correction level) is introduced. Examples are provided to illustrate the conceptual framework for evolving information systems

    A Meta Model for Update in Evolving Information Systems

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    Contains fulltext : 229960.pdf (publisher's version ) (Open Access)20 p

    Evolving information systems: meeting the ever-changing environment

    No full text
    To meet the demands of organizations and their ever-changing environment, information systems are required which are able to evolve to the same extent as organizations do. Such a system has to support changes in all time-and application-dependent aspects. In this paper, requirements and a conceptual framework for evolving information systems are presented. This framework includes an architecture for such systems and a revision of the traditional notion of update. Based on this evolutionary notion of update (recording, correction and forgetting) a state transition-oriented model on three levels of abstraction (event level, recording level, correction level) is introduced. Examples are provided to illustrate the conceptual framework for evolving information systems

    Information systems as a social science: an alternative to the FRISCO formalism

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    The FRISCO Report has initiated an important debate on the discipline of information. Chapters 1, 2 and 6 contribute ideas for all shades of opinion, a Broad View contrasting with Chapters 3, 4 and 5, ā€œthe core of the reportā€. This paper presents a Social View as an alternative to this Core View, which it criticises in two ways. Firstly, it limits the scope of information systems by treating it as an adjunct to software engineering, having no place for key properties of information in organisations and society. Secondly, it does not satisfactorily link its framework of concepts to the empirical world, but relies on the mentalistic notions of ā€˜perceptionsā€™ and ā€˜conceptionsā€™ in the mind of some, unspecified interpreter. The strength of the Core View lies in its formal precision. But a Social View can lead to an alternative formal framework that can place a much wider range of information systems concepts on a firm empirical basis. Thus provides a foundation for information systems as a social science, rather than a branch of applied mathematics. The Core View includes the belief in an objective reality to which we have direct access via the supposedly transparent languages of words, numbers and diagrams, whereas the Social View, without rejecting that position, requires us to explain how we come to construct such knowledge. It also compels us to examine all the other functions we perform with information, especially our construction of social reality. Forced to examine these questions, we have to address many elusive problems, such as the creation of meanings, the role of intentional communication, the construction of time, and the systems of norms we call ā€˜organisationā€™. Finally, the paper re-works the Japan Wines case study used in the FRISCO Report. This shows that the Social View leads to a more detailed analysis of the business problems than the Core View, with as much formal precision, which lends itself to computer interpretation, while also yielding models that are easier for users to interpret
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