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21.
Jrgen Sjdin 《国际能源研究杂志》2002,26(6):475-494
Energy taxation in Sweden is complicated and strongly guides and governs district energy production. Consequently, there is a need for methods for accurate calculation and analysis of effects that different energy tax schemes may have on district energy utilities. Here, a practicable method to analyse influence of such governmental policy measures is demonstrated. The Swedish Government has for some years now been working on a reform of energy taxation, and during this process, several interest groups have expressed their own proposals for improving and developing the system of energy taxation. Together with the present system of taxation, four new alternatives, including the proposed directive of the European Commission, are outlined in the paper. In a case study, an analysis is made of how the different tax alternatives may influence the choice of profitable investments and use of energy carriers in a medium‐sized district‐heating utility. The calculations are made with a linear‐programming model framework. By calculating suitable types and sizes of new investments, if any, and the operation of existing and potential plants, total energy costs are minimized. Results of the analysis include the most profitable investments, which fuel should be used, roughly when during a year plants should be in operation, and at what output. In most scenarios, the most profitable measure is to invest in a waste incineration plant. However, a crucial assumption is, with reference to the new Swedish waste disposal act, a significant income from incinerating refuse. Without this income, different tax schemes result in different technical solutions being most profitable. An investment in cogeneration seems possible in only one scenario. It is also found that particular features of some alternatives seem to oppose both main governmental policy goals, and intentions of the district heating company. Copyright © 2002 John Wiley & Sons, Ltd. 相似文献
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以设防烈度为8度的框架厂房为例,详细分析了活荷载不利布置对框架梁、柱内力的影响,得出何时需要考虑活荷载不利布置、何时不需要考虑活荷载不利布置的结论,可供工程设计参考。 相似文献
24.
轻型钢骨结构低层住宅设计荷载分析 总被引:1,自引:0,他引:1
本文讨论了北美低层钢骨结构住宅结构设计的荷载问题,包括各类荷载的取值和计算方法,以及荷载组合模式,并提出了在我国相关规范没有出台前,在国内进行设计时应该注意的一些问题。 相似文献
25.
Automated currency validation requires a decision to be made regarding the authenticity of a banknote presented to the validation system. This decision often has to be made with little or no information regarding the characteristics of possible counterfeits as is the case for issues of new currency. A method for automated currency validation is presented which segments the whole banknote into different regions, builds individual classifiers on each region and then combines a small subset of the region specific classifiers to provide an overall decision. The segmentation and combination of region specific classifiers to provide optimized false positive and false negative rates is achieved by employing a genetic algorithm. Experiments based on high value notes of Sterling currency were carried out to assess the effectiveness of the proposed solution. 相似文献
26.
制备单根大重量喷涂钼丝的生产研究 总被引:3,自引:0,他引:3
全面系统地介绍了“大坯料轧制开坯-大加工率变形-长线拉伸”制造喷涂钼丝的工艺。重点阐述了Y370、Y250型三辊连轧机实现一火轧制开坯和长线拉伸增加在线碱洗工序对提高喷涂钼丝内部组织结构和外部表面质量的影响。分析了工艺中出现的问题,提出了相应的解决办法。 相似文献
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提出了将水平干管敷设于屋面以解决上供下回系统在建筑层高较低时,水平干管影响室内美观及排气阀浮球不易检修等矛盾的几种设计方案。介绍了几项改善管网运行效果的措施。 相似文献
29.
本文针对我国机床工具产品色彩设计的现状,结合具体实例,对色彩造型的实质做了初步的探讨。分析了色彩造型和色彩装饰两种设计观和实践效果;以色彩与形状关系及作用的论证为引,论述色彩造型的三大功能作用。并提出可供机床工具产品色彩设计参考的具体设计方法和手段。 相似文献
30.
Spaces without northerly orientations have an impact on the ‘energy behaviour’ of a building. This paper outlines possible energy savings and better performance achieved by different zenithal solar passive strategies (skylights, roof monitors and clerestory roof windows) and element arrangements across the roof in zones of cold to temperate climates typical of the central and central-southern Argentina. Analyses were undertaken considering daylighting, thermal and ventilation performances of the different strategies. The results indicate that heating, ventilation and lighting loads in spaces without an equator-facing facade can be significantly reduced by implementing solar passive strategies. In the thermal aspect, the solar saving fraction reached for the different strategies were averaged 43.16% for clerestories, 41.4% for roof monitors and 38.86% for skylights for a glass area of 9% to the floor area. The results also indicate average illuminance levels above 500 lux for the different clerestory and monitor arrangements, uniformity ratios of 0.66–0.82 for the most distributed arrangements and daylighting factors between 11.78 and 20.30% for clear sky conditions, depending on the strategy. In addition, minimum air changes rates of 4 were reached for the most extreme conditions. 相似文献