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阐述了长材轧制中WinLink技术的概念,比较了其在投资成本、运营成本和环境方面的优势,并详细介绍了其在连铸机、感应加热炉、轧机、精轧设备、淬火及回火过程、电气及自动化方面的应用。WinLink瞄准基于产品成本的市场,通过紧凑的产线结构,利用先进的高科技技术方案,将资金和运营成本大幅度地降低,同时也显著地减少能源消耗和CO_2排放,兼具产能高效性、利润最优性和环境友好性等特点。WinLink工艺作为优异的解决方案,有望取代现有生产线,进入迅速发展的市场领域。  相似文献   
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This article presents an architecture to automatically create ad-hoc processes for complex value-added services and to execute them in a reliable way. The uniqueness of ad-hoc processes is to support users not only in standardized situations like traditional workflows do, but also in unique non-recurring situations. Based on user requirements, a service composition engine generates such ad-hoc processes, which integrate individual services in order to provide the desired functionality. Our infrastructure executes ad-hoc processes by transactional agents in a peer-to-peer style. The process execution is thereby performed under transactional guarantees. Moreover, the service composition engine is used to re-plan in the case of execution failures. The work presented in this article was supported by the Swiss National Science Foundation as part of the project MAGIC (FNRS-68155), as well as by the Swiss National Funding Agency OFES as part of the European projects KnowledgeWeb (FP6-507482) and DIP (FP6-507483). Authors in alphabetic order  相似文献   
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The use of coarse-grained lattice models for the modelling of the glassy freezing in of polymer melts is discussed. The bond-fluctuation model is shown to be a reasonable compromise between simulation efficiency and realistic chemical detail. The potential energy, favoring large values of the length of effective bonds, is at low temperatures in conflict with the tendency for dense packing of the effective monomers and this “geometrical frustration” is responsible for the glass transition of this model. It is shown that many physical properties of the model are in surprisingly close agreement with experiments. Open problems and directions for future research are briefly discussed.  相似文献   
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We examined the hypoxic tolerance phenomenon in vitro. Brief exposure to hypoxia induced the production of basic fibroblast growth factor (bFGF) mRNA and protein in rat cortical neurons and protected them from hypoxic injury. Cortical neurons were cultured from 18th-day rat embryos in a serum-free medium and subjected to brief (4 h) and/or prolonged (24 h) hypoxia. Neuronal damage was assessed by quantifying lactate dehydrogenase (LDH) activity in the medium. After brief hypoxia, LDH release was identical to that of the controls, whereas prolonged hypoxia caused a significant increase in LDH release, indicating neuronal death. However, if brief hypoxia was applied 2 days prior to the prolonged hypoxia, no increase in LDH release was observed. The bFGF mRNA expression was assessed with Northern blot and protein immunoreactivity with Western blot analysis. The brief period of hypoxia caused a 2.5-fold increase in bFGF mRNA and considerable bFGF protein expression 1 day later, but prolonged hypoxia caused increase in the expression of bFGF mRNA at 2 days and no protein expression until 3 days after the start of the hypoxia. When cells were subjected to prolonged hypoxia 2 days after brief hypoxia, however, no increase in bFGF mRNA was observed, while bFGF protein was expressed continuously. We also observed that exogenously applied bFGF reduced neuronal injury produced by prolonged hypoxia. The results obtained with this model suggest that brief hypoxia induces bFGF protein and thus tolerance to subsequent lethal hypoxia. Basic FGF might play a role as a tolerance-associated factor in this process. Thus, an in vitro model is useful for assessing the response of cortical neurons to hypoxic stress and for researching new factors related to ischemic tolerance.  相似文献   
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It is shown that the electrical breakdown voltages of polycarbonate film/metal foil capacitors can be increased. This can be achieved by briefly exposing the metal foil in these spirally wound film foil sections to a low-pressure, low-temperature gas plasma. Exposure of tin/lead foil to a 96% CF4/4% O2 gas plasma for four min, for example, produced >500% increase in breakdown voltage of sealed polycarbonate capacitors  相似文献   
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