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91.
性能化设计标准在火灾安全设计中的应用 总被引:10,自引:3,他引:10
随着建筑向着高层化、大型化的趋势发展 ,目前世界上许多国家的建筑设计正逐步地从处方式规范转换到性能化规范。性能化规范的成功实施需要建立性能化设计标准。在建筑火灾安全设计中 ,使用的性能化设计标准包括确定性设计标准和偶然性设计标准。确定性设计标准主要与火灾的发生、发展和蔓延等级 ,以及生命安全等级有关。偶然性设计标准主要关心火灾发生的可能性及产生的后果。文章最后对性能化设计标准的应用情况进行了讨论和总结 相似文献
92.
介绍了金山店铁矿通风系统多级站和机站设计;阐述了该项目的施工,检测及通风效果评估情况;对安全生产提出了全面,系统的建议。 相似文献
93.
Surfactant-based oil dispersant toxicity to developing nauplii of Artemia: effects on ATPase enzymatic system 总被引:1,自引:0,他引:1
The paper deals with the toxicity of a surfactant-based oil dispersant to the ATPase activities of two naupliar stages of Artemia (instar I & II). Both instars were exposed to sub-lethal and lethal concentrations derived from acute toxicity data. The chosen concentrations were near to LOECs and NOECs. An eightfold difference indicated between the instars was instar-exposure time dependent. The most prominent effects were the inhibition and the stimulation of Na+/K+-ATPase and Mg2+-ATPase activities, respectively. The cause of these effects was related to the dispersant components, the surfactants. The pattern stimulation/inhibition of Mg2+-ATPase and Na+/K+-ATPase activities could be used to indicate toxic stress by surfactant-based oil dispersants since previous studies with other contaminants have shown different ATPase activity patterns. 相似文献
94.
Adjusting for the operational environment in studies of performance measurement is very important, otherwise the analysis may lead to unrealistic scores, especially when its influence on costs is high, such as in the water utilities. In this paper, we study the influence of exogenous variables on the water utilities performance by applying conditional efficiency measures based on the order-m method and its probabilistic formulation. We use a sample of 66 water utilities operating between 2002 and 2008, representing about 70% of the Portuguese population. Our research suggests that inefficiency of Portuguese water utilities is substantial for some utilities: several exogenous variables might influence it considerably. For example, regulation has a positive influence on efficiency but when drinking water supply and wastewater services are provided by the same utility or when the wholesale and retail activities are provided together, the performance is lower. The effect of ownership is inconclusive and the variables residential customers, water source, peak factor, and density of customers have a mixed influence on performance which varies according to their scores. 相似文献
95.
This paper compares predictions of the foodchain model SPADE with experimental data for the transfer of (134)Cs and (85)Sr to strawberry plants following acute foliar and soil contamination. The transfer pathways considered in this exercise included direct deposition to fruit, leaf-to-fruit, soil-to-leaf and soil-to-fruit transfers. Following foliar contamination, the difference between predicted and measured radionuclide activity values varied between a factor of 0.5-10 for fruit and 4.5-7 for leaf. Following soil contamination, the difference between predicted and measured values varied between a factor of 3-74 for fruit and 32-44 for leaf. In all cases the difference between measured and predicted values was smaller for (85)Sr than (134)Cs. Measured and predicted activities were higher for leaf than fruit. Both measured and predicted (134)Cs concentrations in fruit and leaf are higher when deposition occurs at ripening than at anthesis. These results confirm the need for more data on fruit, even for Cs and Sr, to support models in predicting the transfer of radionuclides to fruit crops. Ongoing research projects funded by the UK Food Standards Agency aim to provide some data on radionuclide transfer to herbaceous, shrub and tree fruits, which will help improve radiological assessment models in order to provide better protection for consumers. 相似文献
96.
为了研究实施职业安全健康管理体系(OSHMS)对企业职业安全健康管理状况的影响,对百余家已实施与未实施OSHMS的企业进行了调研,在对调研结果分析研究的基础上,采用双对照分析的方法,对已通过OSHMS认证的企业在建立OSHMS前后的职业安全健康管理状况进行对照比较,以及已建立OSHMS与未建立OSHMS的企业的职业安全健康管理状况进行对照比较,研究结果表明,实施OSHMS有利于提高企业职业安全健康管理的整体水平,改善企业的职业安全健康管理状况,使职业安全健康管理更加科学化和规范化。 相似文献
97.
气体、粉尘爆炸灾害及其安全技术 总被引:9,自引:14,他引:9
张景林 《中国安全科学学报》2002,12(5):9-14
对可燃性气体、蒸汽、粉尘的爆炸特性及其抑爆、隔爆安全技术进行了系统的研究 ,并对常见的可燃性气体、蒸汽和粉尘的各种爆炸特性参数和气体抑爆安全技术参数进行了实验测定。根据实验测定结果得到的结论对这种可燃性物质的安全应用具有重要的参考价值 相似文献
98.
小径薄壁管广泛用于工艺管道中,在对其进行无损探伤时,一般采用双壁双影椭圆成像法和双壁重叠成像法,针对小径薄壁管对接焊缝透照成像的特殊要求,具体介绍双壁双影椭圆成像法的透照布置方法。 相似文献
99.
Ensuring that new buildings do not interfere with the recreational and protective functions of the natural system and that the buildings will be useful long enough to protect the investment are among long-term solutions to coastal erosion. We propose that coastal cliff management districts be established for management of eroding high relief shorelines. Such districts would include an imminent failure zone, in which bluff retreat is possible at any time; a migration zone, which allows for long-term shoreline retreat; and a stability control zone in which activities affecting bluff erosion are restricted. Procedures are described for delineating these zones based on geomorphic criteria. If these land use controls are implemented, some shorefront development can be accommodated while retaining valuable characteristics of the natural system. 相似文献
100.
Roy W. Koch Thomas G. Sanders H. J. Morel-Seytoux 《Journal of the American Water Resources Association》1982,18(5):815-821
ABSTRACT: The detection of change in a hydrologic varaible, particularly water quality, is a current problem. A method is presented for testing whether there has been a shift in the mean of a hydrologic variable based on the well established bivariate normal distribution theory. In this technique, the dependent, or target, and the independent, or control, variables are formed as weighted linear combinations of the mean values at a number of locations in a selected target and control area. The weighting factors are determined based on a mathematical programming technique which minimizes the conditional coefficient of variation thereby minimizing the number of observations required to detect a change of a preselected magnitude in the mean of the target area. The result is a situation where a savings in the number of observations required to detect a change is a consequence of adding more stations: the space-time tradeoff. Two applications of the technique are presented, the first using electrical conductivity (EC) data from two sets of river basins and the second using EC data from a set of basins as the target variable and annual discharge as the control. The results indicate that a significant savings in time can be achieved by using this method. 相似文献