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21.
通过对辖区内空气自动监测车仪器与4家公司空气自动监测站仪器的比对分析,得出了空气自动监测车仪器与空气自动监测站仪器的PM10、SO2、NO2相对误差分别为:-32.8%、4.4%、-8.7%,仪器之间显现出良好的线性关系,从比对结果来看,利用空气自动监测车对空气自动监测站进行质量保证和质量控制是可行的.  相似文献   
22.
Current demand analysis methods do not formally cover the case of chronic deficits in quantity or quality of water and sanitation services. These services include drinking water supply (DWS), wastewater and sewage treatment (WST), and municipal solid waste management (MSW). Formal analysis of this case would, at minimum, define the deficit state and evaluate appropriate options for reducing it. This paper proposes for a formal analytical model for municipal sanitation systems (MSS) that operate with deficits in at least one of the constituent services of DWS, WST, or MSW. The model introduces definitions and notation for describing the deficit state for conducting demand analysis on municipal sanitation systems. This model of demand analysis for systems with chronic deficits will hereinafter be referred to as deficit analysis. A case study for Bacoor, Philippines is presented as an example.  相似文献   
23.
Abstract:  We examined factors that may independently or synergistically contribute to amphibian population declines. We used epidemiologic case–control methodology to sample and analyze a large database developed and maintained by the Arizona Game and Fish Department that describes historical and currently known ranid frog localities in Arizona, U.S.A. Sites with historical documentation of target ranid species ( n = 324) were evaluated to identify locations where frogs had disappeared during the study period (case sites) and locations where frog populations persisted (control sites). Between 1986 and 2003, 117 (36%) of the 324 sites became case sites, of which 105 were used in the analyses. An equal number of control sites were sampled to control for the effects of time. Risk factors, or predictor variables, were defined from environmental data summarized during site surveys and geographic information system data layers. We evaluated risk factors with univariate and multifactorial logistic-regression analyses to derive odds ratios (OR). Odds for local population disappearance were significantly related to 4 factors in the multifactorial model. Disappearance of frog populations increased with increasing elevation (OR = 2.7 for every 500 m, p < 0.01). Sites where disappearances occurred were 4.3 times more likely to have other nearby sites that also experienced disappearances (OR = 4.3, p < 0.01), whereas the odds of disappearance were 6.7 times less (OR = 0.15, p < 0.01) when there was a source population nearby. Sites with disappearances were 2.6 times more likely to have introduced crayfish than were control sites (OR = 2.6, p = 0.04). The identification of factors associated with frog disappearances increases understanding of declines occurring in natural populations and aids in conservation efforts to reestablish and protect native ranids by identifying and prioritizing implicated threats.  相似文献   
24.
The application of modifications of the hazard and operability study method (Hazop) to process facilities using computer-based control systems has led to the development of computer Hazop (Chazop) procedures. A number of the Chazop procedures cited in the literature broaden the method and depart from the base documentation of the Hazop method. It is suggested that a robust Chazop method requires implementation at the line-by-line level of detail and as a separate, complementary study using the same base documentation (piping and instrumentation diagrams) as that used in the Hazop method.  相似文献   
25.
2002年3-6月国内安全事故数据   总被引:42,自引:41,他引:1  
统计了2002年3-6月国内发生的各种安全事故871起,包括矿业事故、交通事故、爆炸事故、火灾、毒物泄露和中毒及其他事故.统计表明,在这些事故中,矿业事故最多,占61. 8%,平均每天4.5起事故,其次是交通事故(16.3%)、爆炸事故(6.7%)、火灾(6.0%)、其他事故(5.6%)、毒物泄露和中毒(3.7%).871起事故共死亡2 197人,伤3 321人,死亡人数的百分比分别为矿业事故53.7%、交通事故28.0%、火灾6.1%、爆炸事故5.9%、其他事故5.1%、泄露中毒1.2%;受伤人数的百分比分别为泄露中毒37.4%、交通事故26.9%、爆炸事故14.2%、矿业事故11.8%、其他事故5.3%、火灾4.4%.  相似文献   
26.
企业开展HSE危害识别及风险评估的现状与对策   总被引:1,自引:0,他引:1  
结合本单位建立与实施HSE管理体系实际,分析了企业开展危害识别与风险评估中常见的问题,提出了解决问题的初步方法。  相似文献   
27.
中国可持续社会养老保险的综合评价体系和实证分析   总被引:8,自引:0,他引:8  
我国可持续社会养老保险的综合评价指标体系包括四个层次和三级子系统,内容涉及养老保险人数、机构设置、基金管理和代际平衡四个子目标。应用因子分析模糊综合评价方法对我国1990-2001年养老保险建设状况进行评价,本文认为基金管理,行政管理和代际失衡是影响我国可持续养老保险发展的主要因素。  相似文献   
28.
南宁城市大气污染对人体健康的危害及治理对策   总被引:6,自引:0,他引:6  
南宁市大气属煤烟型污染 ,大气的主要污染物为SO2 、NOx、TSP、降尘 ,虽然随着环境管理和污染治理工作的加强 ,污染物浓度逐年下降 ,但是工业区大气污染仍然较重。污染物流行病学调查显示 :工业区癌症和呼吸系统疾病死亡率均高于全市平均水平 2倍左右 ,城区又高于郊区 2倍 ,大气污染综合指数与呼吸内科门诊就诊人数呈正相关。用邓聚龙的灰色系统理论分析得知污染物对癌症和呼吸系统疾病死亡率有关联 ,关联度从大到小排序为 :TSP >降尘 >SO2 >NOx ,最后提出了大气污染治理的对策。  相似文献   
29.
采用风险分类-要素分析-风险排序的思路,对北京市核与辐射恐怖事件风险进行分析。根据国际上1998—2006年该类恐怖事件的实例,从事件所涉及的材料、场所角度将核与辐射恐怖事件分为6大类。结合北京市的实际情况进行涉核恐怖事件的要素分析,将北京市各类场所划分为4类敏感区并与5类涉核恐怖事件结合起来,得到北京市核与辐射恐怖事件风险构成图。通过风险分析,笔者认为北京市发生核与辐射恐怖事件风险最大的场所为核研究机构,最容易发生的核与辐射恐怖事件类型为涉及放射源的恐怖事件,结合分析结果对从阻止、探测、响应3个层次上提出了奥运核安保工作的反核恐工作建议。  相似文献   
30.
Data collected from the five air-quality monitoring stations established by the Taiwan Environmental Protection Administration in Taipei City from 1994 to 2003 are analyzed to assess the temporal variations of air quality. Principal component analysis (PCA) is adopted to convert the original measuring pollutants into fewer independent components through linear combinations while still retaining the majority of the variance of the original data set. Two principal components (PCs) are retained together explaining 82.73% of the total variance. PC1, which represents primary pollutants such as CO, NO(x), and SO(2), shows an obvious decrease over the last 10 years. PC2, which represents secondary pollutants such as ozone, displays a yearly increase over the time period when a reduction of primary pollutants is obvious. In order to track down the control measures put forth by the authorities, 47 days of high PM(10) concentrations caused by transboundary transport have been eliminated in analyzing the long-term trend of PM(10) in Taipei City. The temporal variations over the past 10 years show that the moderate peak in O(3) demonstrates a significant upward trend even when the local primary pollutants have been well under control. Monthly variations of PC scores demonstrate that primary pollution is significant from January to April, while ozone increases from April to August. The results of the yearly variations of PC scores show that PM(10) has gradually shifted from a strong correlation with PC1 during the early years to become more related to PC2 in recent years. This implies that after a reduction of primary pollutants, the proportion of secondary aerosols in PM(10) may increase. Thus, reducing the precursor concentrations of secondary aerosols will be an effective way to lower PM(10) concentrations.  相似文献   
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