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31.
32.
Nataliya Anisimova 《Energy and Buildings》2011,43(10):2747-2751
The European Union has been demonstrating its adherence to energy efficiency policy in the last decade. At the main EU summits there were stated the requirements to reduce energy consumption in the EU, and to make it sustainable over the long term. The “20-20-20” promise of a 20% share of renewable energies in total EU energy consumption and a 20% reduction of greenhouse gas emissions in the EU by 2020 was determined in 2007 and affirmed in 2008. The paper deals with the evaluation of some ways of reaching a 20% reduction in primary energy demand in housing. For that purpose some measures leading to such a reduction for a dwelling house are estimated. These measures require an additional investment into the energy performance of a building. For the achievement of goals stated by the European Parliament in energy demand it will be necessary to involve a considerable level of financial and technical support in these spheres. An estimation of the amount of supporting program funds is also presented in the paper. 相似文献
33.
Given a changing climate, there is a need to provide data for future years so that practicing engineers can investigate the impact of climate change on particular designs and examine any risk the client might be exposed to. In addition, such files are of use to building scientists in developing generic solutions to problems such as elevated internal temperatures and poor thermal comfort. With the release of the UK Climate Projections (UKCP09) [1], and the publication of a methodology for the creation of probabilistic future reference years using the UKCP09 weather generator [2], it is possible to model future building performance. However, the collapse of the distribution of possibilities inherent in the UKCP09 method into a single reference year or a small number of reference years, potentially means the loss of most of the information about the potential range of the response of the building and of the risk occupants might be subject to. In this paper we model for the first time the internal conditions and energy use of a building with all 3000 example years produced by the UKCP09 weather generator in an attempt to study the full range of response and risk. The resultant histograms and cumulative distribution functions are then used to examine whether single reference years can be used to answer questions about response and risk under a changing climate, or whether a more probabilistic approach is unavoidable. 相似文献
34.
Shay Artzi Adam Kieżun Jaime Quinonez Michael D. Ernst 《Automated Software Engineering》2009,16(1):145-192
Knowing which method parameters may be mutated during a method’s execution is useful for many software engineering tasks.
A parameter reference is immutable if it cannot be used to modify the state of its referent object during the method’s execution. We formally define this notion,
in a core object-oriented language. Having the formal definition enables determining correctness and accuracy of tools approximating
this definition and unbiased comparison of analyses and tools that approximate similar definitions.
We present Pidasa, a tool for classifying parameter reference immutability. Pidasa combines several lightweight, scalable
analyses in stages, with each stage refining the overall result. The resulting analysis is scalable and combines the strengths
of its component analyses. As one of the component analyses, we present a novel dynamic mutability analysis and show how its
results can be improved by random input generation. Experimental results on programs of up to 185 kLOC show that, compared
to previous approaches, Pidasa increases both run-time performance and overall accuracy of immutability inference. 相似文献
35.
地层(体)切片技术自提出后就得到了广泛的应用,不只是在地震沉积学上的应用,很多时候也应用于储层的预测方面,已成为目前全三维地震综合解释的常用手段,同时在应用过程中也出现了新的变化。将地震属性切片分为时间切片、沿层切片、地层切片和地层体切片,着重对地层切片和地层体切片进行了严格区分与详述。在对地层切片技术原理及应用条件分析基础上,结合其在大港油田滨海斜坡区的应用,指出应用地层切片技术时应注意其所适用的地震、地质条件,描述了参考等时面的提取方法及使用技巧等,为地层切片技术的应用提供借鉴。 相似文献
36.
Reference values of the chronoamperometric response at cylindrical and capped cylindrical electrodes
This work provides accurate solutions of the cylinder flux function I(0,1;T), first solved by Jaeger and Clarke, which can serve as reference values for electrochemical amperometric diffusion limited currents at a cylinder, as well as heat fluxes under equivalent conditions (fixed temperature at the cylinder surface). For the capped cylinder of varying lengths, reference values of time-dependent electrochemical currents are provided. Steady state currents at capped cylinders are presented and a function is provided that fits the simulated values to within 1%. All of these are more accurate than in previous works. 相似文献
37.
CFD techniques are used to study the precipitation of barium carbonate in a solid–liquid fluidized bed reactor. Experimental analysis of the hydrodynamic behaviour for a neutralization reaction in the fluidized bed column, followed by CFD simulations is carried out using different reaction models. The Eddy Dissipation model, the Eddy Dissipation model-MTS and the Eddy Dissipation Concept micro-mixing models are tested in order to simulate the acid–base instantaneous reaction. 相似文献
38.
In European Union (EU) buildings consume approximately the 40% of total primary energy. Heat pump (HP) systems have proven to be an efficient and economically viable alternative to conventional systems to provide heating and cooling services in buildings. An effective penetration of this technology in the built environment is critical to achieve the ambitious goals set by the recent EU Directives on energy efficiency and energy performance of buildings. Although this technology is very versatile, its optimal design and management are related to specific climate, operational and economic conditions. The research presented aims to evaluate the performance of technical solutions for heating and cooling in residential buildings, using a “reference building” methodology. The comparison involves performance indicators such as primary energy consumption, CO2 emission and net present cost.The potential improvements with respect to conventional baseline solutions are assessed and the performance gap between air-source and water-source HP systems is shown referring to realistic operational and climate conditions within the Italian territory. The research suggests the possibility of reducing this performance gap by concentrating future research effort on design and control optimization. 相似文献
39.
郜宪林 《计算机工程与应用》2001,37(21):78-80
文章简要介绍了DoDTRM的服务视图、服务域和服务,以及DIICOE的体系结构和段,并在此基础上对TRM服务和DIICOE段进行了比较。 相似文献
40.
Dianne L. Poster Maria J. Lopez de Alda Michele M. Schantz Lane C. Sander Stephen A. Wise Mark G. Vangel 《Polycyclic Aromatic Compounds》2013,33(2):141-191
The National Institute of Standards and Technology (NIST) has recently issued three Standard Reference Materials (SRMs) related to diesel particulate matter: SRM 1650a, Diesel Particulate Matter; SRM 2975, Diesel Particulate Matter (Industrial Forklift); and SRM 1975, Diesel Particulate Extract. These three materials have certified and reference concentrations for selected polycyclic aromatic hydrocarbons (PAHs) including many alkyl-substituted compounds. SRM 1650a is the reissue of an existing material and SRMs 2975 and 1975 represent new materials. The characterization of the PAH content of these three diesel particulate-related SRMs is presented with a discussion of the approach for the certification of PAH concentrations. In addition, the physical and biological characterization of these materials is discussed. A review of customer reported uses of these SRMs in the chemical, physical, and biological sciences is also provided. 相似文献