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This article investigates building thermal mass control of commercial buildings to reduce utility costs with a particular emphasis on the individual impacts of both adaptive comfort criteria and of heat waves. Recent changes in international standards on thermal comfort for indoor environments allow for adaptation to the weather development as manifested in comfort criteria prEN 15251.2005 and NPR-CR 1752.2005 relative to the non-adaptive comfort criterion ISO 7730.2003. Furthermore, since extreme weather patterns tend to occur more frequently, even in moderate climate zones, it is of interest how a building's passive thermal storage inventory responds to prolonged heat waves. The individual and compounded effects of adaptive comfort criteria and heat waves on the conventional and optimal operation of a prototypical office building are investigated for the particularly hot month of August 2003 in Freiburg, Germany. It is found that operating commercial buildings using adaptive comfort criteria strongly reduces total cooling loads and associated building systems energy consumption under conventional and building thermal mass control. In the case of conventional control, total operating cost reductions follow the cooling loads reductions closely. Conversely, the use of adaptive comfort criteria under optimal building thermal mass control leads to both lower and slightly higher absolute operating costs compared to the optimal costs for the non-adaptive ISO 7730. While heat waves strongly affect the peak cooling loads under both conventional and optimal building thermal mass control, total cooling loads, building energy consumption and costs are only weakly affected for both control modes. Passive cooling under cost-optimal control, while achieving significant total cost reductions of up to 13%, is associated with total energy penalties on the order of 1–3% relative to conventional nighttime setup control. Thus, building thermal mass control defends its cost saving potential under optimal control in the presence of adaptive comfort criteria and heat waves. 相似文献
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The branch information system “Hydrogeology” is part of the environmental information system of the federal state Saxony/Germany. The system comprises the decentral and the central data collection, central data storage and management as well as methods for data processing. As yet, data stocks and software were implemented particularly for point related data including applications for data collection, for the interpretation of pumping tests and grain size analysis as well as visualization. Maps are based on the implemented software applications and database structures. These data are an essential help in decisive processes for administrative objectives with a hydrogeologial and environmental background. Databases and methods for area-related data have been built up and already used for generation of maps. 相似文献
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Astrid Heidemann Lassen Frank Gertsen Jens Ove Riis 《Creativity & Innovation Management》2006,15(4):359-372
This paper explores the linkage between the entrepreneurial orientation of established firms and the development of radical innovation. Through five case studies in firms involved in radical innovation, three propositions are developed, suggesting that proactiveness, risk‐taking and autonomy stimulate the development of radical innovation, whereas competitive aggressiveness does not necessarily do so, as radical innovations are directed towards the creation of entirely new arenas of business, where existing competitors are not present. 相似文献
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Applications of optical technologies like vision care, digital imaging or data communication play a decisive role in our daily life. Manipulation of light is mainly done using optical lenses. Beside mineral lenses, transparent plastic materials become more and more important. The optical and mechanical properties of lenses are crucially improved by high‐quality coatings. These includes primarily anti‐reflective coatings to enhance light transmission, hard coats to improve scratch resistance of the sensitive plastic substrates and finally clean coats to inhibit dusting of the lenses and to ease cleaning. In the following we present modern vacuum coating technologies for industrial refinement of optical substrates. The focal point is set to the coating of plastic eyeglass lenses using a revolutionary inline technology. On one hand the technology merges all coating steps in a fully automated system and enables on the other hand the flexible combination of different layer stacks necessary for RX‐production of ophthalmic lenses. This inline technology is available by the coating system OPTICUS. The design of the OPTICUS is described in the last chapter. 相似文献