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421.
为了对民航飞行员人为差错进行系统分析,研究民航业中常见人为差错的分析方法,指出其局限性。基于信息处理过程和事故链原理,从微观的认知过程和宏观的HFACS框架2个层面构建一种新的飞行员人为差错分析模型,并对模型中的情景分析、差错模式与分类、认知机理、差错恢复、差错成因、反馈机制和防御机制等几大核心模块进行阐述,重点介绍认知机理在差错形成中产生的关键影响因素,提出结构化差错分析方法的思路与步骤。该模型为民航飞行员人为差错的产生机理、差错分类和差错成因的分析提供一种新思路,但模型的进一步应用还有待于通过案例分析来验证。 相似文献
422.
为提取灾害性新闻中的基本要素,迅速掌握灾害事件信息和发展趋势,将目标分类和命名实体识别(named entity recognition,NER)相结合,提出改进的灾害新闻3要素提取方法。构建滑动窗检测器搭载不同的分类模型,实现对新闻文本的灾害主题识别与时空位置要素范围判定,结合命名实体识别完成对时空位置要素的精准提取,并以灾害事故信息文本为例进行测试。研究结果表明:通过在火灾、地震和滑坡新闻中进行数据集中测试,发现本文方法相较于LSTM,BILSTM,BILSTM-CRF提取效果更优;本文方法可对大量灾害性新闻的灾害3要素进行识别提取,对灾害信息进行时空规律分析,研究结果可在灾害应急响应中发挥重要作用。 相似文献
423.
1954—2013年湖北省黄石市气溶胶光学厚度与降水关系研究 总被引:1,自引:1,他引:0
通过对地面观测资料进行均一性处理和反演,建立了湖北省黄石市近60年气溶胶光学厚度(AOD)的时间序列,采用气候趋势分析、相关分析等方法,研究了AOD与降水之间的关系.结果表明:近60年黄石市气溶胶光学厚度(AOD)总体上呈显著增加趋势,最大值出现在1991年.随着AOD值的显著增加,年平均降水发生日数显著减少,其中,小雨日数下降更明显,而中雨、大雨日数有增加趋势,暴雨日数的变化趋势不明显.小雨雨量随着AOD值的显著增加而减少,而中雨及以上等级降水量的变化趋势不明显.总之,近60年黄石市气溶胶光学厚度(AOD)的增加,对降水日数和降水量都有一定的影响,其相关性有待进一步研究. 相似文献
424.
《International Journal of Sustainable Engineering》2013,6(4):348-358
Cassava tubers produced under hot, dry and monsoon governed climate in the Salem region, Tamil Nadu, South India, consume together with the about 1000 starch extracting industries daily, 9 millions of litres of groundwater which have to be pumped from a depth of 80 m below ground level. Because of water shortage, adjacent fields are irrigated with organically highly enriched sago factories wastewater and the land becomes unproductive. One-third of the wastewater is presently channelled through a few installed biogas plants with a purification efficiency, biological oxygen demand, of only around 30%. Microbiologically and chemically analysed in- and effluents of biogas plants exhibited nutrient contents sufficient to maintain a rice crop and significantly higher population densities of fermenting bacteria and methanogenic archaea, despite C/N ratio of about 250. CO2 and CH4 emissions from aerobic and anaerobic incubated sago factory biogas plants in- and effluents indicated that the present purification efficiency of 30% can be further enhanced. This investigation has given clues for designing a purification system that connects the already installed biogas plants with a well-aerated, hydro-cultured, constructed wetland and a Stirling motor device for electric power gains and heat distillation, for enabling reuse of process water and saving groundwater. 相似文献
425.
Atmospherically deposited lead in the upper layer of the heavily eroded peatlands of the Peak District, southern Pennines,
UK, reaches concentrations in excess of 1,000 mg kg−1. Erosion of the upper peat layer in this region is releasing lead, associated with eroded peat particles, into the fluvial
system. Understanding the process mechanisms that control dissolved lead concentrations in contaminated peatland streams is
vital for understanding lead cycling and transport in peatland streams. Many headwater streams of the southern Pennines recharge
drinking water reservoirs. Measurements in the Upper North Grain (UNG) study catchment show that mean sediment-associated
and dissolved lead concentrations are 102 ± 39.4 mg kg−1 and 5.73 ± 2.16 μg l−1, respectively. Experimental evidence demonstrates that lead can desorb from suspended sediments, composed of contaminated
peat, into stream waters. In-stream processing could therefore account for the elevated dissolved lead concentrations in the
fluvial system of UNG. 相似文献
426.
Kazuki Morita Muxing Guo Norio Oka Nobuo Sano 《Journal of Material Cycles and Waste Management》2002,4(2):93-101
This research focused on the treatment of steel-making slags to recycle and recover iron and phosphorus. The carbothermal
reduction behavior of both synthesized and factory steel-making slag in microwave irradiation was investigated. The slags
were mixed with graphite powder and heated to a temperature higher than 1873 K to precipitate a lump of Fe–C alloy with a
diameter of 2–8 mm. The larger the carbon equivalent (Ceq, defined in the text), the higher the fractional reduction of iron and phosphorus. An increase in the SiO2 content of slag led to a considerable improvement in the reduction for both iron and phosphorus because of the improvement
in the fluidity of the slags and an increase in the activity coefficient of P2O5 in the slags. The extraction behavior of phosphorus from Fe–P–Csatd alloy was also investigated at 1473 K by carbonate flux treatment. For all the experiments with a processing time longer
than 10 min, the phosphorus in the fluxes could be concentrated to more than 9% (w/w) showing that it could be used as a phosphorus
resource. Compared with K2CO3 flux treatment, that using Na2CO3 was more effective for the extraction of phosphorus, and this was attributed to the lower evaporation of Na2CO3. Finally, a recycling scheme for steel-making slag is proposed.
Received: March 16, 2001 / Accepted: November 12, 2001 相似文献
427.
输煤系统粉尘污染治理技术 总被引:2,自引:0,他引:2
概述了输煤系统粉尘污染治理的现状,分析了采用常规方法治理输煤系统粉尘污染存在的缺点及除尘效率低的原因。介绍了近几年研究开发的2种输煤系统粉尘污染治理新技术的除尘机理、适用范围、系统组成及主要特点。 相似文献
428.
石油化工废气处理技术现状及发展动向 总被引:2,自引:0,他引:2
简要介绍了石油化工废气的主要性质、国内外石油化工废气处理技术的现状、特点和发展动向,提出了国内石油化工企业废气处理的重点事项。 相似文献
429.
毛纺加工过程产生有机卤化物,以人类造成极大危害,近几年越来越受到重视,文章综述了有机卤化物的毛纺加工各工序中的产生,可吸附有机卤化物等的测定及其处理方法和相关立法状况。 相似文献
430.