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Conceptual Level (conceptual + level)
Selected AbstractsA reference model for grid architectures and its validationCONCURRENCY AND COMPUTATION: PRACTICE & EXPERIENCE, Issue 11 2010Wil van der Aalst Abstract Computing and data-intensive applications in physics, medicine, biology, graphics, and business intelligence require large and distributed infrastructures to address the challenges of the present and the future. For example, process mining applications are faced with terrabytes of event data and computationally expensive algorithms. Computer grids are increasingly being used to deal with such challenges. However, grid computing is often approached in an ad hoc and engineering-like manner. Despite the availability of many software packages for grid applications, a good conceptual model of the grid is missing. This paper provides a formal description of the grid in terms of a colored Petri net (CPN). This CPN can be seen as a reference model for grids as it clarifies the basic concepts at the conceptual level. Moreover, the CPN allows for various kinds of analyses ranging from verification to performance analysis. We validate our model based on real-life experiments using a testbed grid architecture available in our group and we show how the model can be used for the estimation of throughput times for scientific workflows. Copyright © 2009 John Wiley & Sons, Ltd. [source] Getting ready for user involvement in a systematic reviewHEALTH EXPECTATIONS, Issue 2 2009Elizabeth Smith BSc MSc PhD Abstract Objective, This paper aims to support the critical development of user involvement in systematic reviews by explaining some of the theoretical, ethical and practical issues entailed in ,getting ready' for user involvement. Background, Relatively few health or social care systematic reviews have actively involved service users. Evidence from other research contexts shows that user involvement can have benefits in terms of improved quality and outcomes, hence there is a need to test out different approaches in order to realize the benefits of user involvement and gain a greater understanding of any negative outcomes. Design, Setting up a service-user reference group for a review of user involvement in nursing, midwifery and health visiting research involved conceptualizing user involvement, developing a representation framework, identifying and targeting service users and creating a sense of mutuality and reciprocity. Setting and participants, Recruitment was undertaken across England by two researchers. Members from 24 national consumer organizations were selected to participate in the review. Main variables studied, Learning was gained about finding ways of navigating consumer networks and organizations, how best to communicate our goals and intentions and how to manage selection and ,rejection' in circumstances where we had stimulated enthusiasm. Results and conclusions, Involving service users helped us to access information, locate the findings in issues that are important to service users and to disseminate findings. User involvement is about relationships in social contexts: decisions made at the early conceptual level of research design affect service users and researchers in complex and personal ways. [source] Effects of warm-supplementing kidney yang (WSKY) capsule added on risperidone on cognition in chronic schizophrenic patients: a randomized, double-blind, placebo-controlled, multi-center clinical trialHUMAN PSYCHOPHARMACOLOGY: CLINICAL AND EXPERIMENTAL, Issue 6 2008Zhen-hua Chen Abstract Objective To evaluate the effects of warm-supplementing kidney yang (WSKY) capsule added on risperidone on cognition in chronic schizophrenic patients. Methods A randomized, double-blind, placebo-controlled, multi-center clinical trial was conducted. All 200 patients who met the DSM-IV diagnostic criteria for schizophrenia were randomly assigned to double-blind treatment with WSKY capsule (n,=,100) or placebo (n,=,100) added on risperidone for 8 weeks. The primary outcome measure was the cognitive function assessment assessed by the classic form of the Wisconsin Card Sorting Test (WCST) at baseline and week 8. The secondary outcome measures were assessed including the positive and negative symptoms scale (PANSS), the social disability screening schedule (SDSS), and the Hamilton rating scale for depression (HAM-D-17) at baseline, week 2, week 4, and week 8. The extrapyramidal side effects were assessed each week using the abnormal involuntary movement scale (AIMS) and rating scale for extrapyramidal side effects (RSESE), while adverse events were assessed using treatment emergent symptoms scale (TESS) as additional indicators of tolerability throughout the trial. Results The response rates of the WSKY group for the number of completed categories (CC), errors responses number (ER), perseveringly errors responses number (PER), and conceptual level (CL) of WCST assessment were significantly higher than those of placebo. The reduction in the SDSS score from baseline to endpoint was significantly greater in the WSKY group than those in the placebo. There were no significant differences in the response rates for the correct responses number, perseveringly responses number (PR) of WCST between the treatment groups. The improvements in the WCST indexes, PANSS score, HAM-D-17 score were no significant differences from baseline to endpoint between the two groups at week 8.There were no significant differences in AIMS, RSESE, and TESS compared patients treated with WSKY capsule with those in placebo during treatment. Conclusion WSKY capsule added on risperidone may improve cognitive function, social function of the chronic schizophrenic patients, and the WSKY safely during treatment. Copyright © 2008 John Wiley & Sons, Ltd. [source] The value of environmental modelling languages for building distributed hydrological modelsHYDROLOGICAL PROCESSES, Issue 14 2002Derek Karssenberg Abstract An evaluation is made of the suitability of programming languages for hydrological modellers to create distributed, process-based hydrological models. Both system programming languages and high-level environmental modelling languages are evaluated based on a list of requirements for the optimal programming language for such models. This is illustrated with a case study, implemented using the PCRaster environmental modelling language to create a distributed, process-based hydrological model based on the concepts of KINEROS-EUROSEM. The main conclusion is that system programming languages are not ideal for hydrologists who are not computer programmers because the level of thinking of these languages is too strongly related to specialized computer science. A higher level environmental modelling language is better in the sense that it operates at the conceptual level of the hydrologist. This is because it contains operators that identify hydrological processes that operate on hydrological entities, such as two-dimensional maps, three-dimensional blocks and time-series. The case study illustrates the advantages of using an environmental modelling language as compared with system programming languages in fulfilling requirements on the level of thinking applied in the language, the reusability of the program code, the lack of technical details in the program, a short model development time and learnability. The study shows that environmental modelling languages are equally good as system programming languages in minimizing programming errors, but are worse in generic application and performance. It is expected that environmental modelling languages will be used in future mainly for development of new models that can be tailored to modelling aims and the field data available. Copyright © 2002 John Wiley & Sons, Ltd. [source] Using Reference Models within the Enterprise Resource Planning LifecycleAUSTRALIAN ACCOUNTING REVIEW, Issue 22 2000MICHAEL ROSEMANN ERP-specific reference models describe on a conceptual level the structure and functionality of enterprise resource planning solutions. However, these models focus on depicting executable processes and do not take into account tasks related to business engineering, system selection, implementation or change. This paper discusses how reference process models can be used within the entire ERP lifecycle. All phases of the ERP lifecycle have individual requirements for the management of the relevant knowledge. It will be shown how extended reference models can serve as a knowledge repository for enterprise resource planning. This paper includes several pragmatic recommendations for managers involved in ERP projects. [source] La diffusion d'une innovation portant les germes de son plafonnement: la réutilisation des hémodialyseurs au QuébecCANADIAN PUBLIC ADMINISTRATION/ADMINISTRATION PUBLIQUE DU CANADA, Issue 3 2001Daniel Lozeau Sommaire: L'objectif de cette recherche est d'identifier les facteurs de diffusion d'une innovation - la réutilisation des hémodialyseurs (rh) - ainsi que de son plafonncment marqué par la controverse, à travers les motivations et stratégies des groupes d'acteurs clés. Plus particulièrement, cette étude vise à situer le rôle de la " médecine fondée sur des données probantes "dans la dynamique de la diffusion de cette innovation. Nous partons du constat que la rh est une pratique reconnue pour les économies qu'elle génère tout en étant perçue par certains comme risquée pour la santé des usagers et du personnel. Les résultats de notre étude montrent que la diffusion de la rh au Québec, loin d'avoir pris son assise sur des données empiriques solides, a plutôt résulté de comportements sociaux d'imitation à la faveur de contacts directs entre des centres de dialyse voisins qui subissaient alors de fortes pressions de leurs autorités afin de réduire leurs dépenses. Cependant, l'ampleur des investissements nécessaires à l'introduction de cette pratique, la perspective de devoir négocicr I'achat de matériel dédiéà la rh auprès d'un monopole, ainsi que les stratégies commerciales de fournisseurs peu motivés à promouvoir la vente de matériel de rh au détriment de celle, plus lucrative, d'hémodialyseurs en grande quantité (lorsque non réutilisés), ont grandement réduit l'attrait économique dc la rh aux yeux des dirigeants de centres de dialyse. L'incapacité des données empiriques à endiguer les craintes soulevées par les risques associés à la rh a eu la double conséquence (1) dc mener au plafonnement de cette activité et (2) d'induire des centres de dialysc qui effectuaient déjà la rh à se doter d'une gestion envers les patients basée sur la non transparence et la contrainte. Sur le plan conceptuel, les résultats de cette étude montrent que ce n'est que dans la mesure où les facteurs sociaux et d'intérêts (dynamiquc institutionnelle) sont pris en compte et qu'ils convergent avec les critères de rationalité technique, qu'une innovation améliore ses chances de se diffuser et de s'enraciner dans une organisation. Considérant ces conclusions, quelques propositions sont énonées dans le but d'améliorer le potentiel d'implantation de la rh en facilitant la prise en compte des données empiriques dans les centres de dialyse, tout en leur procurant un meilleur rapport de force vis-à-vis leurs fournisseurs et afin que les patients et le personnel clinique y trouvent davantage leur intérêt. Abstract: The purpose of this research is to identify the factors in the diffusion of an innovation - hemodialyzer re-use - and the controversy surrounding the levelling off of its use, by looking at the motivations and strategies of key actors. More particularly, this study focuses on the role of "evidence-based medicine" in the diffusion of this innovation. Starting with the observation that hemodialyzer re-use is recognized for its cost-savings while being perceived by some to be a health risk for both users and staff, our findings show that diffusion of this practice in Quebec, far from being based on solid empirical data, was instead influenced by the social phenomenon of imitation that resulted from direct contact with local dialysis centres that were at the time under great pressure from their management to reduce expenditures. The cost-savings of hemodialyzer re-use for the people managing the dialysis centres was, however, greatly reduced by several factors: the considerable investments needed to introduce this practice; the prospects of having to negotiate with a monopoly to purchase the hemodialyzer-dedicated equipment; and the commercial strategies of suppliers who have little interest in promoting the sale of equipment for hemodialyzer re-use over the more lucrative sale of large quantities of hemodialyzers (when not re-used). The ineffectiveness of empirical data in allaying fears of the risks associated with the practice of hemodialyzer re-use has had the dual effect of 1) causing this activity to level off, and 2) causing dialysis centres already involved in hemodialyzer re-use to adopt an approach to patient management that is based on non-transparency and constraint. On the conceptual level, our findings show that the likelihood of an organization adopting an innovation increases when social factors and interest factors (such as the institutional dynamic) are taken into account and align with criteria of technical rationality. Given these conclusions, we put forward some proposals for improving the potential of hemodialyzer re-use by facilitating the dialysis centres' consideration of empirical data. As well, our proposals are aimed at obtaining a stronger position for the centres with regard to their suppliers and at ensuring that both patients and clinic staff benefit more from the practice of hemodialyzer re-use. [source] The English School, International Relations, and Progress,INTERNATIONAL STUDIES REVIEW, Issue 2 2005Balkan Devlen This essay evaluates the English School,a prominent approach to the study of international relations,as a "research enterprise" (James 2002). Our exploration begins with an introduction of a "continuum of aggregation" that conveys a given research enterprise, such as the English School, at different conceptual levels. The English School's axioms along with its negative and positive heuristics are identified and evaluated based on the classics and more recent works from Wight, Bull, and others. Conclusions and prospects for further development of the English School complete the review. [source] | |||||||||||||