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介绍两种震害损失估算方法 总被引:1,自引:0,他引:1
本文介绍了两种震害损失估算方法:全概率法和单位面积法。并据此法对宁夏、青海等地震害作了估算。 相似文献
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讨论了单宽流量横向分布参数b_0和b的范围,并按水位级、断面形和低流速状作了研究。这对无实测流场资料的河流进行污染带计算,具有应用前景。 相似文献
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Junsoo Lee John A. List Mark C. Strazicich 《Journal of Environmental Economics and Management》2006,51(3):354-370
In this paper, we examine temporal properties of 11 natural resource real price series from 1870 to 1990. Recent studies by Ahrens and Sharma [Trends in natural resource commodity prices: deterministic or stochastic? J. Environ. Econom. Manage. 33(1997)59–74], Berck and Roberts [Natural resource prices: will they ever turn up? J. Environ. Econom. Manage. 31(1996)65–78], and Slade [Grade selection under uncertainty: least cost last and other anomalies, J. Environ. Econom. Manage. 15(1988)189–205], among others, find that many non-renewable resource prices have a stochastic trend. We revisit this issue by employing a Lagrangian multiplier unit root test that allows for two endogenously determined structural breaks with and without a quadratic trend. Contrary to previous research, we find evidence against the unit root hypothesis for all price series. Our findings support characterizing natural resource prices as stationary around deterministic trends with structural breaks. We additionally show that both pre-testing for unit roots with breaks and allowing for breaks in the forecast model can improve forecast accuracy. Overall, the results in this paper are important in both a positive and normative sense; without an appropriate understanding of the dynamics of a time series, empirical verification of theories, forecasting, and proper inference are potentially fruitless. 相似文献
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付怀录 《石油化工环境保护》1997,(3):55-58
辽化“九五”期间由于生产装置改扩,装置“三废”排放量的增加,促使环保装置改造的必要性。通过对环保项目改造的评估,可以得出江化“九五”期间所增污染物总量.经治理削减,完全可以控制在1995年排行总量指标之内. 相似文献
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Organic waste products, potentially harmful to the human health and the environment, are primarily produced in the synthesis stage of manufacturing processes. Many such synthetic unit processes, such as halogenation, oxidation, alkylation, nitration, and sulfonation are common to a large number of organic chemical manufacture in several different industry sectors. The environmental impact of organic chemical syntheses can be significantly reduced by incorporating cleaner unit processes. A review of research and development activities shows that progress is already being made along these lines worldwide, and commercialization of cleaner organic technologies is also proceeding. 相似文献
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A teacher of ours used to say, “Like ice in a fire, something for nothing you will never acquire”, which is a poetic equivalent of “there is no such a thing as a free lunch”. Human economies are dependent on high quality fossil fuels and will likely continue depending on them for some time to come. Value of a resource is not only what one pays for it, or what can be extracted from it, but also value can be attributed to the “effort” required in its production. In this analysis we apply the emergy synthesis method to evaluate the work invested by the geobiosphere to generate the global storages of fossil energy resources. The upgrading of raw resources to secondary fuels is also evaluated. The analysis relies on published estimates of historic, global net primary production (NPP) on land and oceans, published preservation and conversion factors of organic matter, and assessments of the present total global storages of coal, petroleum, and natural gas. Results show that the production of coal resources over geologic time required between 6.63E4 (±0.51E4) seJ/J and 9.71E4 (±0.79E4) seJ/J, while, oil and natural gas resources required about 1.48E5 (±0.07 E5) seJ/J and 1.70E5 (±0.06E5) seJ/J, respectively. These values are between 1.5 and 2.5 times larger than previous estimates and acknowledge a far greater power of fossil fuels in driving and shaping modern society. 相似文献
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简述了采用法定计量单位的重要性。列举了现行环境保护标准中计量单位不规范使用的实例,对计量单位不规范使用的原因进行了分析,提出,环境保护标准中关于项目(指标)涉及量和单位的,应对量做出明确的说明;在应用国外文献时,尤其要注意计量单位的规范性;在标准发布和出版前,加强计量单位规范使用的审核。 相似文献