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11.
Standardized business documents are a prerequisite for successful information exchange in electronic business transactions. The United Nations Centre for Trade Facilitation and eBusiness (UN/CEFACT) provides a conceptual modeling approach, called Core Components, used by Business Partners (BPs) for defining business document models (BDMs). BDMs are essential for defining service interfaces in service-oriented systems. However, in such a highly dynamic environment with ever-changing market demands, BPs are confronted with the need to revise their BDMs resulting in a multitude of different versions. BPs may dictate the use of new versions of BDMs, but small- and medium-sized enterprises (SMEs) may not always adopt new BDM versions due to the cost and effort involved, inhibiting automated electronic information exchange. In this article, we propose a framework including (i) a classification of the impact of changes in BDMs, (ii) evolution templates for the automated transformation of business documents between different BDM versions, and (iii) mitigation strategies for evolutions where fully-automated and semantic-preserving transformations are not feasible. Having such a framework at hand provides SMEs with a low-cost and light-weight approach for dealing with evolving market requirements and hence evolving business documents. Finally, we analyze the evolution of UN/CEFACT''s Cross Industry Invoice which has been mandated to be used for electronic invoicing within the European Union as well as present a critical discussion of the evolution templates defined.  相似文献   
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Different types of enzymes such as lipases, several phosphatases, dehydrogenases, oxidases, amylases and others are well suited for the reactions in SC-CO2. The stability and the activity of enzymes exposed to carbon dioxide under high pressure depend on enzyme species, water content in the solution and on the pressure and temperature of the reaction system. The three-dimensional structure of enzymes may be significantly altered under extreme conditions, causing their denaturation and consequent loss of activity. If the conditions are less adverse, the protein structure may be largely retained. Minor structural changes may induce an alternative active protein state with altered enzyme activity, specificity and stability.  相似文献   
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The steps that create physical shape data in a typical logic device design-to-reticle flow are cell layout, place and route, tapeout, OPC or RET, data fracture, and reticle build. Here, we define OPC as the transformation of reticle data to compensate for lithographic and process distortions so that the final wafer pattern is as close to the target pattern-the designed layout-as possible. We define RETs as the general class of transformations for reticle data that aim to improve the patterning process window; therefore, OPC is a subset of RET. DFM is traditionally considered to be implemented at the cell layout or routing stages of this flow. Examples include the optimization of a layout based on critical-defect area, the addition of redundant contacts and vias, wire spreading, upsizing of metal landing pads, and the addition of dummy metal tiles to improve the planarity after chemical-mechanical planarization (CMP). We presented a detailed analysis of these techniques in an earlier work. In contrast, this article analyzes the possibility of extending these traditional methods into the OPC stage and introduces new post-tapeout RET methods for improving printability.  相似文献   
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The present study attempts to identify the antigen-presenting cells in the retina, utilizing bone marrow-transplanted chimeric rats. Two types of chimeras were used: one produced by transplanting bone marrow cells from F1 hybrids of Lewis and Brown Norway (BN) into sublethally irradiated Brown Norway rats (LBN/F1-->BN), followed by adoptive transfer of S-antigen-specific T cells obtained from Lewis rats; the second produced by transplanting bone marrow cells from BN rats into sublethally irradiated F1 hybrids (BN-->LBN/F1), followed by adoptive transfer of S-antigen-specific T cells obtained from F1 hybrids. As controls, Lewis, F1 hybrids and BN rats also received adoptive transfer of syngeneic uveitogenic T cell lines. All animals were killed on the seventh day after adoptive transfer and their eyes and pineal glands were analysed immunohistochemically, utilizing antibody directed against Lewis specific MHC class II molecules(OX-3). The analyses revealed the development of uveoretinitis and pinealitis in both types of chimeras and in the Lewis and F1 hybrid rats. BN rats did not develop uveoretinitis. OX-3-positive cells were found in the retina and the pineal glands of both types of chimeras, and in the Lewis and F1 hybrid rats but not in the BN rats. These cells in the retina expressed dendritic morphology and perivascular distribution. Retinal pigment epithelia, Müller cells and the vascular endothelia of both chimeras, the two strains, and the F1 hybrid rats did not demonstrate OX-3-positive staining. These results suggest that the bone marrow-derived cells in the retina and pineal gland may present S-antigen to T cells, initiating the cascade of uveoretinitis and pinealitis.  相似文献   
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In this paper we present a method for automatic interpolation between adjacent discrete levels of detail to achieve smooth LOD changes in image space. We achieve this by breaking the problem into two passes: We render the two LOD levels individually and combine them in a separate pass afterwards. The interpolation is formulated in a way that only one level has to be updated per frame and the other can be reused from the previous frame, thereby causing roughly the same render cost as with simple non interpolated discrete LOD rendering, only incurring the slight overhead of the final combination pass. Additionally we describe customized interpolation schemes using visibility textures. The method was designed with the ease of integration into existing engines in mind. It requires neither sorting nor blending of objects, nor does it introduce any constrains in the LOD used. The LODs can be coplanar, alpha masked, animated, impostors, and intersecting, while still interpolating smoothly.  相似文献   
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