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441.
Altamash Ahmad Baig Farshad Kimiaghalam Rakesh Kumar JuanLi Ma Alan S. Fung 《International Journal of Green Energy》2020,17(8):476-487
ABSTRACT An eQUEST model was developed to conduct a simulation study of a natural gas engine-driven heat pump (GEHP) for an office building in Woodstock, Ontario, Canada. Prior to the installation of the GEHP, the heating and cooling demands of the office building were provided by rooftop units (RTUs), comprising of natural gas heater and electric air conditioner. Energy consumption for both GEHP and RTUs were monitored for operation in alternating months. These recorded energy consumptions along with weather data were used in the regression analysis. The developed eQUEST models were validated and calibrated with the regression analysis results with respect to the ASHRAE Guideline 14–2014. The eventual models were then applied to investigate the potential annual energy consumption, greenhouse gas (GHG) emission and energy cost savings achieved by using the GEHP in Woodstock, and other cities in Canada, particularly in Ontario. 相似文献
442.
443.
Caroline Michel Marie-Thérèse Giudici-Orticoni Frauke Baymann Mireille Bruschi 《Water, Air, & Soil Pollution: Focus》2003,3(3):161-169
The treatment of soils and ground waters polluted by heavy metals is of economical and environmental interest. Reduction of Cr(VI) to the less toxic Cr(III) associated to its precipitation is a potentially useful process for bioremediation. In order to develop ecological processes using micro-organisms, we have compared various sulfate-reducing bacteria for enzymatic reduction of chromate. The best Cr(VI) reductase activity was obtained with Desulfomicrobium norvegicum. Despite morphological changes induced by the presence of chromate, this strain can grow in the presence of up to 500 M Cr(VI) and can decontaminate waters polluted by Cr(VI) when seeded in bioreactors. We have demonstrated the ability of several metalloenzymes (cytochromes c
3 and hydrogenases) to reduce chromate. Biophysical investigations of the chromate/protein interaction in order to get further informations on the mechanism of metal reduction by cytochromes c
3 are under the way. 相似文献
444.
Vellidis G Smith MC Leibowitz SG Ainslie WB Pruitt BA 《Environmental management》2003,31(2):0301-0312
In a climate of limited resources, it is often necessary to prioritize restoration efforts geographically. The synoptic approach
is an ecologically based tool for geographic prioritization of wetland protection and restoration efforts. The approach was
specifically designed to incorporate best professional judgment in cases where information and resources are otherwise limited.
Synoptic assessments calculate indices for functional criteria in subunits (watersheds, counties, etc.) of a region and then
rank the subunits. Ranks can be visualized in region-scale maps which enable managers to identify areas where efforts optimize
functional performance on a regional scale. In this paper, we develop a conceptual model for prioritizing watersheds whose
wetlands can be restored to reduce total sediment yield at the watershed outlet. The conceptual model is designed to rank
watersheds but not individual wetlands within a watershed. The synoptic approach is valid for applying the sediment yield
reduction model because there is high demand for prioritizing disturbed wetlands for restoration, but there is limited, quantitative,
accurate information available with which to make decisions. Furthermore, the cost of creating a comprehensive database is
prohibitively high. Finally, because the model will be used for planning purposes, and, specifically, for prioritizing based
on multiple decisions rather than optimizing a single decision, the consequence of prioritization errors is low. Model results
cannot be treated as scientific findings. The conclusions of an assessment are based on judgement, but this judgement is guided
by scientific principles and a general understanding of relevant ecological processes. The conceptual model was developed
as the first step towards prioritizing of wetland restoration for sediment yield reduction in US EPA Region 4. 相似文献
445.
During 1999-2000, Ethiopia was brought to the edge of a major disaster, with some 10 million people estimated to be in need offood assistance at the height of the crisis. A repeat of the catastrophic famine of 1984-5 was avoided, but the numbers of people affected, the loss of life and the destruction of livelihoods made this one of the most serious crises in the Horn of Africa in the past 15 years. The humanitarian community has been slow to recognise the lessons of 1999-2000, and there have been surprisingly few attempts to conduct a serious, post-event evaluation of the overall crisis and response. The label famine averted' seems to summarise the crisis to the satisfaction of most parties involved. This paper reviews the crisis, the events that led up to it and the response effort. It examines thefactors that contributed to making this crisis so serious, in order to draw conclusions and note issues that are relevant to current thinking about disaster preparedness and response - in Ethiopia and elsewhere. Some of the lessons learned from the 1999-2000 crisis are not new. However, the veryfact that mistakes have been repeated should be a lesson to the humanitarian community. 相似文献
446.
广东省台风灾害特点及减灾对策 总被引:17,自引:5,他引:12
根据《台风年鉴》等台风资料,分析了广东省台风灾害的特点,讨论了台风灾害对广东省经济,社会及生态环境的影响,并针对广东省台风灾害的特点提出了减轻台风灾害的对策。 相似文献
447.
This paper describes a fuzzy hierarchical analytic approach to determine the weighting of subjective judgments. In addition,
it presents a nonadditive fuzzy integral technique to evaluate a green engineering industry case as a fuzzy multicriteria
decision-making (FMCDM) problem. When the investment strategies are evaluated from various aspects, such as economic effectiveness,
technical feasibility, and environmental regulation, it can be regarded as an FMCDM problem. Since stakeholders cannot clearly
estimate each considered criterion in terms of numerical values for the anticipated alternatives/strategies, fuzziness is
considered to be applicable. Consequently, this paper uses triangular fuzzy numbers to establish weights and anticipated achievement
values. By ranking fuzzy weights and fuzzy synthetic utility values, we can determine the relative importance of criteria
and decide the best strategies. This paper applies what is called a λ fuzzy measure and nonadditive fuzzy integral technique
to evaluate the synthetic performance of green engineering strategies for aquatic products processors in Taiwan. In addition,
we demonstrate that the nonadditive fuzzy integral is an effective evaluation and appears to be appropriate, especially when
the criteria are not independent. 相似文献
448.
449.
依靠科学进步,促进防灾减灾 总被引:2,自引:0,他引:2
以科学技术工作为主线 ,系统地总结了陕西省减灾协会 10年来 ,从事自然灾害综合预测、防灾减灾科学研究、学术交流和科普宣传教育等方面的做法、经验和所取得的初步成效 ,以及如何建设好减灾科技社团的体会 相似文献
450.