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241.
全球自然灾害频发、强度不断增强,且城市化进程飞速发展,其所带来的相关城市灾害风险与日俱增.在重视灾害预报、预警的同时,城市灾害应急处置工作的有效组织与开展,亦是至关重要.把人工智能和城市灾害学知识相结合,通过构建灾害应急处置专家系统来解决该问题是目前的一个研究方向.本文运用案例推理等人工智能领域知识进行相关问题研究,阐述了如何对典型城市灾害案例进行知识化存储处理,给出了典型城市灾害分类推理规则和应急救援案例匹配计算方法.最后,利用VC++和CLIPS相结合,构建了基于案例决策的城市灾害应急处置专家系统.通过研究,充分验证了该模型方法的可行性,对于提高城市应急处置能力具有很好的现实意义.  相似文献   
242.
O3 increment is mainly caused by changes in meteorology rather than emissions. Emission reduction is effective to reduce O3 nationwide, especially in summer. Strengthened NOx controls are necessary to meet the ambient O3 standard. We have quantified the impacts of anthropogenic emissions reductions caused by the Air Pollution Control Action Plan and changes in meteorological fields between 2013 and 2017 on the warm-season O3 concentration in China using a regional 3D chemical transport model. We found that the impact on daily maximum eight-hour (MDA8) O3 concentration by the meteorological variation that mostly increased O3 was greater than that from emission reduction, which decreased O3. Specifically, the control measures implemented since 2013 in China have reduced SO2, NOx, PM2.5, and VOC emissions by 33%, 25%, 30%, and 4% in 2017, while NH3 emissions have increased by 7%. The changes in anthropogenic emissions lowered MDA8 O3 by 0.4–3.7 ppb (0.8%–7.6%, varying by region and month), although MDA8 O3 was increased slightly in some urban areas (i.e. North China) at the beginning/end of warm seasons. Relative to 2013, the average 2 m temperature in 2017 shows increments in North, North-east, East, and South China (0.34℃–0.83℃) and decreases in Central China (0.24℃). The average solar radiation shows increments in North, North-east, and South China (7.0–9.7 w/m2) and decreases in Central, South-west, and North-west China (4.7–10.3 w/m2). The meteorological differences significantly change MDA8 O3 by -3.5–8.5 ppb (-8.2%–18.8%) with large temporal variations. The average MDA8 O3 was slightly increased in North, North-east, East, and South China. The response surface model suggests that the O3 formation regime transfers from NOx-saturated in April to NOx-limited in July on average in China.  相似文献   
243.
针对330 kV超高压输电线路绝缘架空地线无专用接地线,设计一种串接电阻的新型接地装置,以避免当绝缘架空地线存在过大感应电压时因瞬间直接接地产生的电弧伤害。通过对某330 kV同塔双回输电线路不同情况下绝缘架空地线上产生的感应电压进行仿真分析,为新型接地装置的电气参数选取提供依据,同时详细设计了其机械结构。对新型接地装置进行了现场应用,验证了其相较于传统接地线具有的便携性及安全性优势。  相似文献   
244.
Estimated anthropogenic Hg emission was 11.9 tons in Pearl River Delta for 2014. Quantifying contributions of emission sources helps to provide control strategies. More attentions should be paid to Hg deposition around the large point sources. Power plant, industrial source and waste incinerator were priorities for control. A coordinated regional Hg emission control was important for controlling pollution. We used CMAQ-Hg to simulate mercury pollution and identify main sources in the Pearl River Delta (PRD) with updated local emission inventory and latest regional and global emissions. The total anthropogenic mercury emissions in the PRD for 2014 were 11,939.6 kg. Power plants and industrial boilers were dominant sectors, responsible for 29.4 and 22.7%. We first compared model predictions and observations and the results showed a good performance. Then five scenarios with power plants (PP), municipal solid waste incineration (MSWI), industrial point sources (IP), natural sources (NAT), and boundary conditions (BCs) zeroed out separately were simulated and compared with the base case. BCs was responsible for over 30% of annual average mercury concentration and total deposition while NAT contributed around 15%. Among the anthropogenic sources, IP (22.9%) was dominant with a contribution over 20.0% and PP (18.9%) and MSWI (11.2%) ranked second and third. Results also showed that power plants were the most important emission sources in the central PRD, where the ultra-low emission for thermal power units need to be strengthened. In the northern and western PRD, cement and metal productions were priorities for mercury control. The fast growth of municipal solid waste incineration were also a key factor in the core areas. In addition, a coordinated regional mercury emission control was important for effectively controlling pollution. In the future, mercury emissions will decrease as control measures are strengthened, more attention should be paid to mercury deposition around the large point sources as high levels of pollution are observed.  相似文献   
245.
Environmental Science and Pollution Research - Due to the merits of their high adsorption and convenient separation, magnetic graphene-based composites have become a promising adsorbent in terms of...  相似文献   
246.
Wang  Shengli  Yan  Linlin  Guan  Xiaohui  Jia  Yanping  Song  Lianfa  Zhang  Haifeng 《Environmental Chemistry Letters》2019,17(4):1831-1837
Environmental Chemistry Letters - Hydroxyl radicals are commonly produced either by metal activation or by using external energy. However, the application of these methods is limited by low working...  相似文献   
247.
本文从企业的生产成本、资金成本和管理成本等三个方面,谈到了企业在生产经过中降低成本的有效途径和方法,从而增强企业在激烈的市场环境中的竞争力,达到“增收节支”的目的.  相似文献   
248.
油田开发项目中大气环境影响预测方法研究   总被引:2,自引:0,他引:2  
针对油田开发过程中大气污染源点多面广的特点,选用适当的大气环境预测方法已成为问题关键,使用网格处理,分别计算点源(高斯模式)和面源(H-G模式)的污染贡献量,得到预测结果,并佐以百色油田的应用实例,得出:多源扩散模式(H-G模式)可以反映油田开发多源污染的叠加效果;H-G模式计算简便,要求参数少且容易获得,与复杂模式的计算结果相一致,能满足油田开发项目大气环境影响评价的要求。  相似文献   
249.
活性炭纤维电极法处理草浆造纸黑液的应用研究   总被引:25,自引:1,他引:25  
用活性炭纤维(ACF)电极法和酸析、凝聚处理加电极组合方法,对造纸黑液进行处理。结果表明,电极法处理黑液,CODcr、色度去除率分别达64.25%和94%;“酸化+电解(45min)+Fenton试剂”的综合治理方法效果较好,CODcr、色度去除率分别达94.2%和99.6%,出水近乎清澈透明。  相似文献   
250.
作者对西岭凤地山锡矿床的成矿地质条件,特别是火山构造、岩浆演化与成矿的关系进行了研究,认为:西岭锡矿是一个与火山侵出相碎斑熔岩时、空、成因关系密切的次火山热液脉状锡矿床。根据西岭锡矿的地质环境和成矿物理化学条件、矿质、水介质来源建立了理想的成矿模式。进而指出粤东斑岩锡矿的远景。西岭锡矿类型的确定,对粤东和赣南火山岩地区锡矿普查具有重要意义。  相似文献   
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