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91.
Do time‐averaged,whole‐building,effective volatile organic compound (VOC) emissions depend on the air exchange rate? A statistical analysis of trends for 46 VOCs in U.S. offices 下载免费PDF全文
We used existing data to develop distributions of time‐averaged air exchange rates (AER), whole‐building ‘effective’ emission rates of volatile organic compounds (VOC), and other variables for use in Monte Carlo analyses of U.S. offices. With these, we explored whether long‐term VOC emission rates were related to the AER over the sector, as has been observed in the short term for some VOCs in single buildings. We fit and compared two statistical models to the data. In the independent emissions model (IEM), emissions were unaffected by other variables, while in the dependent emissions model (DEM), emissions responded to the AER via coupling through a conceptual boundary layer between the air and a lumped emission source. For 20 of 46 VOCs, the DEM was preferable to the IEM and emission rates, though variable, were higher in buildings with higher AERs. Most oxygenated VOCs and some alkanes were well fit by the DEM, while nearly all aromatics and halocarbons were independent. Trends by vapor pressure suggested multiple mechanisms could be involved. The factors of temperature, relative humidity, and building age were almost never associated with effective emission rates. Our findings suggest that effective emissions in real commercial buildings will be difficult to predict from deterministic experiments or models. 相似文献
92.
The work reported here addresses load matching improvement in Net Zero Energy Buildings (Net-ZEBs). The related relevant literature shows that currently research work is mainly focused on improving the load matching of individual buildings. In this paper the concept of a Cooperative Net Zero Energy Community (CNet-ZEC) is introduced, extending discussion to the enhancement of load matching at a wider community level. Both building and community levels are compared in order to assess the work proposed here, through the analysis of three distinct scenarios where five Net-ZEBs work individually or in community.The results presented here were obtained through a detailed simulation based on 1-min resolution stochastic load profiles and recorded weather data. The results indicate that over the period of a year the CNet-ZEC has the potential to increase the electrical demand covered by onsite electricity generation up to 21% and the on-site generation that is used by the building up to 15%. The following elements are considered by the CNet-ZEC in order to produce those results: (i) demand heterogeneity of the buildings integrating the community; (ii) the higher number of controllable devices; and (iii) the potential higher amount of energy available to satisfy the community demand. 相似文献
93.
梳理国内市场对"阻燃"概念的认识,对建筑物内通信电缆阻燃特性的认识误区进行剖析,提出需根据电缆的阻燃分级来辨识电缆的阻燃能力,以选择符合建筑物所要求的阻燃级别的通信电缆。 相似文献
94.
Brett Pollard 《施工技术》2012,41(3):1-8,21
This paper reviews the major North American and Australian sustainability rating tools to determine how they measure building energy performance. It then reviews the major building energy simulation so... 相似文献
95.
高层建筑的优势是占地面积相对较小而功能完备,因此此类项目已成为城市建设工程当中的一项重点。所以,在高层建筑施工中,必须高度重视施工技术,以确保建筑质量和建筑施工的安全性。 相似文献
96.
Previous research suggests that environmental certification (EC) affects rental rates in non-residential buildings, but there is still little understanding of how tenants differentiate such buildings from those without EC. This paper examines whether and how tenants perceive value creation in EC premises in Sweden. The findings (based on 29 questionnaire responses and 14 interviews with tenants in EC buildings) inform landlords and tenants on the development of EC strategies for improved organizational outcomes. EC creates value for tenants principally as support for their environmental management and reporting (e.g., low energy demand). EC is important for tenants internally, raising employee environmental awareness and improving employee attraction and retention. Tenants are generally positive about employee morale, indoor environmental quality (IEQ) and rental costs. However, it is not clear if such perceptions are dependent on features of modern premises in general, such as new fixtures, fittings and furnishings, and space-efficiency or from some EC-related feature. Tenants do not identify health or productivity increase in their EC premises. Findings suggest that the research focus should be shifted from investigating health and productivity increases through IEQ improvement to understanding the motivational improvement through value alignment with employees through EC. 相似文献
97.
Alternative approach to compute shear amplification in high‐rise reinforced concrete core wall buildings using uncoupled modal response history analysis procedure 下载免费PDF全文
Tahir Mehmood Pennung Warnitchai Munir Ahmed M.Irshad Qureshi 《The Structural Design of Tall and Special Buildings》2017,26(4)
The seismic response of the high‐rise reinforced concrete (RC) wall structures is really complicated as several vibration modes other than the fundamental mode normally contribute significantly to the response—commonly recognized as ‘higher mode effects’. Response spectrum analysis (RSA) procedure, which can account for higher mode effects, is usually employed to compute the seismic design demand for the high‐rise structures. Recent studies show that the inelastic seismic force demands obtained from the rigorous nonlinear response history analysis procedure are much larger than the seismic force design demands obtained from the code‐based RSA procedure for the high‐rise RC wall structures. Though, the nonlinear response history analysis procedure is widely accepted for its ability to provide the most accurate estimate of nonlinear seismic responses, the obtained responses are generally so complex that it is quite difficult for engineers to grasp the overall picture of the responses and gain some insight into them and use them to understand the cause of high seismic demands. Another important issue related to the nonlinear seismic response prediction of the high‐rise RC wall structures is the realistic and accurate numerical modeling of RC walls. In this study, a simplified but reasonably accurate procedure called the uncoupled modal response history analysis procedure is used to interpret the complex nonlinear behavior of high‐rise RC wall structures. Moreover, a finite element model based on modified compression field theory is employed for accurate numerical modeling of RC walls by incorporating the axial‐flexure‐shear interaction. This study, by making use of a better computer modeling approach and an in‐depth analysis by modal decomposition, aims to resolve some of the unanswered questions regarding realistic prediction of nonlinear seismic demands of high‐rise structures. 相似文献
98.
近年来,随着建筑技术发展,建筑物高度在不断增加。只有在设计过程中充分调查研究、合理设计,才能有效发挥消防装备的最大功效。因此,本文针对现今的高层建筑设计中的防火设计要点进行细致地分析。 相似文献
99.
当真正把建筑看作是城市环境的一部分时,建筑设计不仅仅是简单意义的单纯设计,单纯满足使用功能、技术和经济等方面的要求已不再是设计的所有内容。本文就现代高层建筑设计理论、原则以及相关应该注意事项进行探讨。 相似文献
100.
主要研究高层建筑施工管理中存在的问题,探索其解决措施。我们认为高层建筑有着很强的复杂性和综合性,涉及到很多专业,需要对施工方案和工序进行合理地组织,采取一系列措施保证安全,控制施工进度,才能发挥高层建筑的最大经济效益。 相似文献