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Curved graphs are proposed that relate the shape of the box cross-section of an arch to the real ultimate lateral strength for various values of length, support conditions and of height of the cross-section.The real ultimate lateral strength of a series of arches is determined and the results obtained are then compared to those provided by Sakimoto and Komatsu [1].Elastic–plastic steel material and geometric non-linearity hypotheses, residual stresses, and initial lateral deflection are all taken into consideration with respect to the real ultimate lateral strength.  相似文献   
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The aggregation behavior of C.I. Basic Violet 10 in the presence of poly(sodium 4-styrenesulfonate) was modified, as a consequence of short-range interactions. In aqueous acidic media, the cationic dye forms hydrophobic ion pairs with polymeric benzene sulfonate groups which tend to aggregate in H-contacts, this tendency being readily influenced by the relative concentration of the macromolecule with respect to that of the dye. In the case of dilute aqueous dye solutions (≤10?4 M), for which the probability of dye self-aggregation is small, C.I. Basic Violet 10 self-contacts are forced in the presence of a moderate excess of poly(sodium 4-styrenesulfonate). At dye concentrations >10?4 M, for which the probability of dye self-aggregation increases, dye-dye contacts are minimized in the presence of a large excess of the polymer. Hence, the luminescence of dye solutions can be tuned insorar as, that of dilute dye solutions is quenched whilst that of concentrated dye solutions can be enhanced. This behavior was not observed for other polyelectrolytes such as poly(sodium vinylsulfonate), or the more hydrophobic poly(sodium 2-(N-acrylamido)-2-methyl-propanesulfonate).  相似文献   
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Web-based translation memory (TM) is a recent and little-studied development that is changing the way localisation projects are conducted. This article looks at the technology that allows for the sharing of TM databases over the internet to find out how it shapes the translator’s working environment. It shows that so-called pre-translation—until now the standard way for clients to manage translation tasks with freelancers—is giving way to web-interactive translation. Thus, rather than interacting with their own desktop databases as before, translators now interface with each other through server-based translation memories, so that a newly entered term or segment can be retrieved moments later by another translator working at a remote site. The study finds that, while the interests of most stakeholders in the localisation process are well served by this web-based arrangement, it can involve drawbacks for freelancers. Once an added value, technical expertise becomes less of a determining factor in employability, while translators lose autonomy through an inability to retain the linguistic assets they generate. Web-based TM is, therefore, seen to risk disempowering and de-skilling freelancers, relegating them from valued localisation partners to mere servants of the new technology.  相似文献   
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We present a novel CWDM metropolitan multiple-access ring network based on optical switching of packets according to their wavelength. Each node within the MAN is identified by a combination of wavelength and numerical address. Hence, nodes are able to drop packets presenting a particular wavelength and numerical address, but can insert packets in any wavelength into the ring. This configuration allows wavelength sharing, as several nodes are identified by the same wavelength (but different numerical addresses), and simplifies switching requirements since the set of numerical addresses is reduced. We analyze the viability and scalability of such a network, determining the number of nodes supported by the network under different traffic scenarios and wavelength resources. The impact of switching time on network performance is also analyzed in order to determine which switching technology should be employed when implementing the network. An erratum to this article is available at .  相似文献   
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Numerous studies have reported on the use of enzymes in wineries to facilitate the extraction of grape phenolics and to aid colour stability, although no clear conclusions were reached. Information concerning the enzymatic activities of industrial preparations is very difficult to obtain despite its importance. The aim of this work was to characterise and quantify the activities of six macerating enzyme preparations to optimise their use, and to study their effect on the chromatic characteristics of a Monastrell wine. The results indicate that differences exist in the type of enzymatic activities present in the preparations and in their concentration. The chromatic characteristics of the resulting wines, both at the end of alcoholic fermentation and after 12 months of storage in stainless steel tanks, showed differences with the use of the different maceration enzymes when comparing with control wine, although very little differences were observed between the different enzyme treatments. The enzyme-treated wines showed, at the end of alcoholic fermentation, a higher OD280 and tannin content, and after 12 months, a higher colour intensity too. The main effect of all the preparations was an increase in the total phenol content, probably by facilitating the release of skin tannins.  相似文献   
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