1,010 research outputs found

    On the Management of Sharing Design, Knowledge

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    This paper presents the approach and results of a research project that develops an environment for sharing design knowledge. The project implements a design modelling approach that allows designers to capture design concepts into formally defined typologies. With these, designers can build flexible design models and have full control over definitions and structures used to represent design concepts. The presented research project uses this dynamic modelling approach in the development of Design Knowledge Servers that function in a network to provide a distributed multi-user environment for sharing design knowledge. Such a network serves the requirements of collaborative design and is useful for other purposes, such as publication of formalised product datasheets. The paper briefly provides the background of the knowledge modelling approach underlying this project and describes the design and implementation issues of the Design Knowledge Servers and the services they provide

    Supporting collaboration design by type recognition and knowledge sharing

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    In collaborative design projects, designers are required to share and identify design knowledge, which is an aspect of design that can benefit significantly from formalisation of design knowledge. On the other hand, working with formalised design knowledge should not impede the creativity in design by restricting the design process and limiting the freedom of manipulating design information. The research project reported in this article provides an approach to design modelling that manifests a high level of flexibility and extensibility of the formalised design knowledge. The design process is supported in this approach by tools that help identify the design rationale through type recognition and by Internet-based services that allow designers to share design models and design knowledge in a well-structured manne

    A Distributed Object Model for CSCW in the Construction Industry

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    Information about products for the construction industry is increasingly often provided to designers in digital ways that enable them to apply the information directly in the design process. Digital product catalogues are provided using various media and formats and several initiatives are taken by the industry and by CAD developers to integrate this kind of information into CAD systems. Generally, current practice is to distribute the information to designers, for example, by using CD-ROMs or a website where the information can be downloaded. In our research we recognise that distributing information in this manner detaches it from the business processes in the construction supply chain, which is a major disadvantage. The project presented in this paper concerns the implementation in the Dutch construction industry of a methodology for sharing product information through a distributed object model. The methodology, which is called Concept Modelling, forms a generic basis for the support of collaborative design, but is applied in this project to the integration of information from the supply chain in the design process. Through the distributed object model, design information and product information can be integrated while the actual data objects remain at their source. This enables the supply chain to provide information of a high semantic level to designers while keeping the control over the information and maintaining the relationship of the information with their business processes. The advantages of this approach in which information is shared, rather than exchanged, are numerous. Redundancy of information is minimised, consistency is improved, and updated information is available immediately. Moreover, design and construction processes can benefit significantly from the dynamic aspects of accessing information that is tied to business processes in the supply chain. For example, product selection during design can be based on latest information on product details, prices, production methods, and variants of products. This information can be provided to designers automatically and on demand

    A feature based approach to modelling architectural information

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    An Ontology Web Language Notation of the Industry Foundation Classes

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    In this paper we describe and discuss an OWL notation of IFCs, its advantages over generic XML schema representation, its various fields of possible application, and our implementation of it in a multi-agent framework

    Invariance of the relativistic one-particle distribution function

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    The one-particle distribution function is of importance both in non-relativistic and relativistic statistical physics. In the relativistic framework, Lorentz invariance is possibly its most fundamental property. The present article on the subject is a contrastive one: we review, discuss critically, and, when necessary, complete, the treatments found in the standard literature

    Modulation by epidermal growth factor of the basal 1,25(OH)2D3 receptor level and the heterologous up-regulation of the 1,25(OH)2D3 receptor in clonal osteoblast-like cells

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    The effects of epidermal growth factor (EGF) on basal 1,25-dihydroxyvitamin D3 (1,25-(OH)2D3) receptor level and on parathyroid hormone (PTH)-induced 1,25-(OH)2D3 (OH)2D3 receptor up-regulation were studied in the phenotypically osteoblastic cell line UMR 106. EGF in concentrations exceeding 0.1 ng/ml reduced the number of 1,25(OH)2D3 binding sites without changing the binding affinity. Maximal reduction was 30% at about 1 ng/ml. This reduction was independent of a change in cAMP content. EGF dose-dependently attenuated both PTH-induced 1,25(OH)2D3 receptor up-regulation and PTH-stimulated cAMP production without and effect on the ED50 of the PTH effects. For both PTH responses the IC50 and the maximal effective dose were similar, 0.1 ng/ml an 1 ng/ml EGF, respectively. Reduction was first seen at 0.01 ng/ml EGF. At this concentration. EGF reduced PTH-stimulated 1,25-(OH)2D3 receptor binding without an inhibition of the cAMP response. Time-course studies with 1 ng/ml EGF revealed that at 2 h preincubation EGF reduced the heterologous up regulation by PTH, and maximal inhibition was seen after 4 h. In contrast, PTH-stimulated cAMP production was just significantly inhibited only after 6 h, with 60% inhibition after 24 h preincubation. The effects of prostaglandin E2 and forskolin on both 1,25(OH)2D3 binding and cAMP production were inhibited in a similar fashion. On the other hand, dibutyryl cAMP- and 3-isobutyl-1-methylxanthinestimulated 1,25(OH)2D3 binding were not affected by EGF. Taken together, our results demonstrate that EGF reduces both the basal number of 1,25(OH)2D3 binding sites and the heterologous up-regulation of the 1,25(OH)2D3 receptor. The current data suggest that EGF reduces heterologous upregulation of the 1,25(OH)2D3 receptor independent of as well as dependent on the cAMP messenger system. The EGF effect is not primarily located at the PTH receptor, at cAMP phosphodiesterase, or at protein kinase A level

    Ecologische ontwikkeling in een voor menselijke activiteiten gesloten gebied in de Nederlandse Waddenzee: Tussenrapportage drie jaar na sluiting (najaar 2008)

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    De Nederlandse overheid heeft in november 2005 een referentiegebied ingesteld om te voldoen aan de internationale verplichting dat voldoende grote gebieden in de Waddenzee worden aangewezen waarbinnen geen exploitaties en verstorende activiteiten mogen plaatsvinden. In dit project wordt de nadruk gelegd op het volgen van de ontwikkeling van het ecosysteem in een voor de garnalen- en schelpdiervisserij gesloten gebied (Schild en Boschwad) en dit te vergelijken met een gebied waar garnalenvisserij zal blijven (Zuidoost Lauwers en Spruit). Om de ontwikkeling van dit ongestoorde gebied te volgen zijn er vóór de instelling van dit gebied bemonsteringen uitgevoerd door IMARES (2002, 2003 en 2005). Na de instelling van het referentiegebied (november 2005) worden jaarlijks bemonsteringen uitgevoerd. In dit rapport wordt een weergave gegeven van de ontwikkelingen in het referentiegebied drie jaar na sluiting. Prioriteit gaat hierbij uit naar benthische mariene fauna (jaarlijks), maar ook de litorale mosselbanken (jaarlijks), de visfauna (elke 5 jaar), de zeehondenpopulatie (elke 5 jaar) en de vogelvoorkomens (elke 5 jaar) worden in dit project meegenomen
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