32 research outputs found

    AMCIS 2002 Panels and Workshops II: Spreadsheet-Based DSS Curriculum Issues

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    When challenged to justify the value of information systems (IS) research, decision support systems (DSS) is usually cited as one the most compelling examples of where IS research made the transition successfully from theoretical academic journals into the real-world . In light of this assessment, it is somewhat surprising that offerings of DSS courses waned over the years. This paper identifies several possible reasons for the decline in DSS course offerings and suggests innovative approaches using spreadsheets for breathing new-life into this cornerstone of the IS field

    Lateralization of mesial temporal lobe epilepsy with chronic ambulatory electrocorticography

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    OBJECTIVE: Patients with suspected mesial temporal lobe (MTL) epilepsy typically undergo inpatient video-electroencephalography (EEG) monitoring with scalp and/or intracranial electrodes for 1 to 2 weeks to localize and lateralize the seizure focus or foci. Chronic ambulatory electrocorticography (ECoG) in patients with MTL epilepsy may provide additional information about seizure lateralization. This analysis describes data obtained from chronic ambulatory ECoG in patients with suspected bilateral MTL epilepsy in order to assess the time required to determine the seizure lateralization and whether this information could influence treatment decisions. METHODS: Ambulatory ECoG was reviewed in patients with suspected bilateral MTL epilepsy who were among a larger cohort with intractable epilepsy participating in a randomized controlled trial of responsive neurostimulation. Subjects were implanted with bilateral MTL leads and a cranially implanted neurostimulator programmed to detect abnormal interictal and ictal ECoG activity. ECoG data stored by the neurostimulator were reviewed to determine the lateralization of electrographic seizures and the interval of time until independent bilateral MTL electrographic seizures were recorded. RESULTS: Eighty-two subjects were implanted with bilateral MTL leads and followed for 4.7 years on average (median 4.9 years). Independent bilateral MTL electrographic seizures were recorded in 84%. The average time to record bilateral electrographic seizures in the ambulatory setting was 41.6 days (median 13 days, range 0-376 days). Sixteen percent had only unilateral electrographic seizures after an average of 4.6 years of recording. SIGNIFICANCE: About one third of the subjects implanted with bilateral MTL electrodes required >1 month of chronic ambulatory ECoG before the first contralateral MTL electrographic seizure was recorded. Some patients with suspected bilateral MTL seizures had only unilateral electrographic seizures. Chronic ambulatory ECoG in patients with suspected bilateral MTL seizures provides data in a naturalistic setting, may complement data from inpatient video-EEG monitoring, and can contribute to treatment decisions

    Metabolite Cross-Feeding Enhances Virulence in a Model Polymicrobial Infection

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    Microbes within polymicrobial infections often display synergistic interactions resulting in enhanced pathogenesis; however, the molecular mechanisms governing these interactions are not well understood. Development of model systems that allow detailed mechanistic studies of polymicrobial synergy is a critical step towards a comprehensive understanding of these infections in vivo. In this study, we used a model polymicrobial infection including the opportunistic pathogen Aggregatibacter actinomycetemcomitans and the commensal Streptococcus gordonii to examine the importance of metabolite cross-feeding for establishing co-culture infections. Our results reveal that co-culture with S. gordonii enhances the pathogenesis of A. actinomycetemcomitans in a murine abscess model of infection. Interestingly, the ability of A. actinomycetemcomitans to utilize L-lactate as an energy source is essential for these co-culture benefits. Surprisingly, inactivation of L-lactate catabolism had no impact on mono-culture growth in vitro and in vivo suggesting that A. actinomycetemcomitans L-lactate catabolism is only critical for establishing co-culture infections. These results demonstrate that metabolite cross-feeding is critical for A. actinomycetemcomitans to persist in a polymicrobial infection with S. gordonii supporting the idea that the metabolic properties of commensal bacteria alter the course of pathogenesis in polymicrobial communities

    Modified differential evolution: a greedy random strategy for genetic recombination

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    Over the past three decades Evolutionary Algorithms have emerged as a powerful mechanism for finding solutions to large and complex problems. A promising new evolutionary algorithm known as Differential Evolution (DE) was recently introduced and has garnered significant attention in the research literature. This paper introduces a modification to DE that enhances its rate of convergence without compromising solution quality. DE was recently shown to outperform several well-known stochastic optimization methods on an extensive set of test problems. Our Modified Differential Evolution (MDE) algorithm utilizes selection pressure to develop offspring that are more fit to survive than those generated from purely random operators. We demonstrate that MDE requires less computational effort to locate global optimal solutions to well-known test problems in the continuous domain.Artificial intelligence Evolutionary algorithms Non-linear programming Optimization

    Software Architecture in DoD Acquisition: An Approach and Language for a Software Development Plan

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    The right software architecture is essential for a software-intensive system. Meeting behavioral requirements and providing quality attributes such as real-time performance, reliability, and maintainability are essential architectural drivers. Because an architecture comprises the earliest, most important, and most far-reaching design decisions, making sure that the architecture will be fit for purpose is one of the most powerful, technical risk mitigation strategies available to a program office. This technical note covers one avenue of exercising architectural control-the Software Development Plan (SDP). The report provides an example approach and corresponding SDP language that enable software architecture to play a central role in the technical and organizational management of a software development effort. The example is drawn from an actual SDP written by a major U.S. Department of Defense contractor in a weapon-system procurement. The intent is to provide an example for other acquisition organizations to use (and adapt as appropriate) in their own procurements. While the example is based on a contracting approach with a lead system integrator, it can serve as a model for using an architecture-centric approach effectively to unify and manage software development across multiple suppliers, as found in the conventional prime-with-subcontractors acquisition context

    Software Architecture in DoD Acquisition: A Reference Standard for a Software Architecture Document

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    The right software architecture is essential for a software-intensive system to meet its functional requirements as well as its quality requirements that govern real-time performance, reliability, maintainability, and a host of other quality attributes. Because an architecture comprises the earliest, most important, and most far-reaching design decisions, it is important for an acquisition organization to exercise its oversight prerogatives with respect to software architecture. Having the right software architecture documentation is a prerequisite for managing and guiding a software development effort and conducting in situ software architecture evaluations. Conducting an architecture evaluation to determine the software architecture's fitness for purpose is one of the most powerful, technical risk mitigation strategies available to a program office. This report provides an example reference standard for a Software Architecture Document (SAD). An acquisition organization can use this standard to contractually acquire the documentation needed for communicating the software architecture design and conducting software architecture evaluations. The example used in this report is drawn from an actual SAD written by a major U.S. Department of Defense contractor in a weapon system acquisition. The intent of this report is to provide an example for other acquisition efforts to use (and adapt as appropriate) in their own procurements

    The U.S. Army’s Common Avionics Architecture System (CAAS) Product Line: A Case Study

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    This report is one in a series of Carnegie Mellon Software Engineering Institute case studies of organizations that have adopted a software product line approach for developing a family of software-intensive systems. The U.S. Army's Technical Applications Program Office (TAPO) has adopted a product line approach for the avionics software used for the Army's special operations helicopters. That software is based on Rockwell Collins' Common Avionics Architecture System (CAAS). The product line has evolved beyond its original scope and is now being adopted to include other Army aviation platforms such as cargo and utility helicopters. This case study describes the acquisition context and organizations involved in the product line, the history behind the development and evolution of the product line, its application to the mission of the Army's special operations helicopters, the Army's motivation for adopting a product line, specifics of the product line approach, and the underlying CAAS system and software architecture. The case study also highlights the software product line accomplishments, examines the results and lessons learned from TAPO's and Rockwell Collins' perspective, and discusses future considerations
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