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91.
企业安全文化评估与企业安全行为的质化研究 总被引:6,自引:5,他引:1
通过总结国内外各种不同的安全文化概念,归纳分析了国内外较为流行的近10种安全文化建立模式。在研讨文献的基础上,通过深入访谈、焦点小组与参与观察,归纳构造了一套共11个维度,总题项为152题的安全文化评估量表。通过对选定企业的实证问卷调查,进行统计分析,采用多元逐步回归分析等方法对安全文化各评核因素及整体安全文化进行预测,并以百分数呈现其整体的安全文化现状水平。通过基于扎根理论的各种质化研究方法,对案例企业的安全文化建设和企业安全行为进行研究,得到了7点关于企业安全行为的研究发现,并提出了相应的改进建议。 相似文献
92.
水安全及城市水安全研究进展与趋势 总被引:2,自引:1,他引:1
归纳和总结国内外水安全及城市水安全相关研究实践及其所用的评价指标体系,并对几种常用模型与方法的应用情况及其各自的特点进行分析,针对目前水安全及城市水安全研究中存在的主要问题,指出水安全及城市水安全进一步研究的方向:从自然、生态环境、社会经济、人文4个基本方向,以系统性、持续性、动态性和层次性4个特征为基础,分析水安全及城市水安全的概念与内涵;根据研究区域特征及其主要水安全问题建立评价指标体系;以研究者对各个模型的理解程度及驾驭能力为准则选用或改造现有模型与方法;针对加强城市应急水源地建设、突发性水安全事件应急预案、湿润地区水安全等问题开展研究。 相似文献
93.
刘德良 《湖南环境生物职业技术学院学报》2001,7(3):60-64
园林树木栽培学是一门实践性很强的有关园林绿化领域的专业课、必修课.1995年以来,本人在园林树木栽培学各论教学中尝试重点讲解、课堂点评的教学方法,取得了较好的教学效果. 相似文献
94.
Past changes and possible future variations in the nature of extreme precipitation and flood events in Central Europe and
the Alpine region are examined from a physical standpoint. An overview is given of the following key contributory physical
processes: (1) the variability of the large-scale atmospheric flow and the associated changes of the North-Atlantic storm
track; (2) the feedback process between climate warming and the water cycle, and in particular the potential for more frequent
heavy precipitation events; and (3) the catchment-scale hydrological processes associated with variations in major river flooding
events and that are related to land-use changes, river training measures, and shifts in the proportion of rain to snowfall.
In this context an account is provided of the possible future forecasting and warning methodologies based upon high-resolution
weather prediction and runoff models. Also consideration is given to the detectability of past (future) changes in observed
(modeled) extreme events. It is shown that their rarity and natural fluctuation largely impedes a detection of systematic
variations. These effects restrict trend analysis of such events to return periods of below a few months. An illustration
using daily precipitation from the Swiss Alps does yield evidence for pronounced trends of intense precipitation events (return
period 30 days), while trends of stronger event classes are not detectable (but nevertheless can not be excluded). The small
detection probability for extreme events limits possible mitigation of future damage costs through an abatement of climate
change alone, and points to the desirability of developing improved early forecasting/warning systems as an additional no-regret
strategy.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
95.
96.
G20峰会空气质量保障机制的构建 总被引:2,自引:2,他引:0
为进一步做好G20峰会空气质量保障工作,在大气污染联防联控机制的基础上,建立G20峰会空气质量保障机制,形成专项工作小组,按照空气质量保障组织框架运行,为精准保障提供空气质量预报、污染态势特征及评估、措施执行情况及效果、污染溯源等管控技术支撑。2016年9月,G20峰会期间杭州市空气质量总体优良,8月24日至9月7日G20峰会前后杭州市PM_(2.5)、PM_(10)、SO_2、NO_2、CO、O_3等污染物浓度同比2015年分别下降40%、40%、37%、56%、22%、7%,在该机制的推动下空气质量保障工作圆满完成。 相似文献
97.
研究了不同分析方法、去浊度手段和预处理方式对地表水总磷测定的影响。结果表明:钼酸铵分光光度法在跨界水体联合监测中较连续流动分析法、氯化亚锡还原光度法、孔雀绿-磷钼杂多酸分光光度法更为适用;在水样没有色度的情况下,采用浊度-色度补偿法和离心法都能有效消除浊度干扰,相对误差±10%;预处理方式的不同是导致各监测单位测定结果可比性差的最关键因素。 相似文献
98.
挥发性有机物污染土壤样品采样方法比较 总被引:1,自引:0,他引:1
以苯系物污染土壤样品的采集为例,比较了4种不同采样方法导致样品检测结果的差异。其中,方法 1将样品装填至广口瓶内并压实密封,方法2采用非扰动采样器采集10 g样品后转移至加有10 mL甲醇保护剂的Vial瓶中密封,方法 3用非扰动采样器采集10 g样品后直接将其密封于采样器内,方法 4用Encore采样器采样后将其密封于采样器内。结果表明,方法 2采集样品的检出率最高,其余3种方法的差异不明显,方法 2采集样品的检出结果 71%以上都大于其余3种方法。而且,对于挥发性较强的苯与甲苯,以方法 2采集的样品91%以上都大于其余3种方法,最大及平均检出浓度高出2~3个数量级。5种不同土质样品检测结果表明,对于有机质含量较低的细砂,方法2的最高及平均检出浓度均高于其余3种方法 1~3个数量级,差异随土壤有机质含量的升高而降低。可见,对于苯系物及挥发性强于苯系物的其他挥发性有机物污染土壤样品的采集,方法 2效果最优,可指定为VOCs污染场地土壤样品的采样方法。 相似文献
99.
Kees van Leeuwen 《Environmental management》1990,14(6):779-792
In a recently published annex to the National Environmental Policy Plan of the Netherlands (1989), attention was paid to ecotoxicological
effects assessment. The proposed procedure was based on the advice of the Health Council of the Netherlands (1989) on risk
assessment of toxic chemicals for ecosystems. The various extrapolation methods described by the Health Council are critically
discussed in this paper. The extrapolation method of Van Straalen and Denneman (1989) is evaluated for eight chemicals and
11 aquatic species. Conclusions are drawn about the quality and quantity of the ecotoxicological data needed for aquatic effects
assessment. For the soil—a compartment that is often at risk—ecotoxicological effects assessment is not possible because suitable
ecotoxicological test methods still have to be developed. 相似文献
100.
Myron A. Peck Paul E. Fell Elizabeth A. Allen Jennifer A. Gieg Carl R. Guthke Michael D. Newkirk 《Environmental management》1994,18(2):283-293
Macroinvertebrates were examined on an impounded valley marsh in Stonington, Connecticut, that has changed from aTypha-dominated system to one with typical salt-marsh vegetation during 13 years following the reintroduction of tidal exchange.
Animal populations on this restored impounded marsh were evaluated by comparing them with populations on a nearby unimpounded
valley marsh of roughly the same size. Populations of the high marsh snail,Melampus bidentatus Say, were quantitatively sampled along transects that extended from the water-marsh edge to the upland; those of the ribbed
mussel,Geukensia demissa Dillwyn, were sampled in low marsh areas on transects along the banks of creeks and mosquito ditches. The occurrence of other
marsh invertebrates also was documented, but their abundance was not measured. The mean density ofMelampus was 332±39.6 SE/m2 on the restored impounded marsh and 712±56.0 SE/m2 on the unimpounded marsh. However, since snails were larger on the restored impounded marsh, the difference in snail biomass
was less pronounced than the difference in snail density. MeanMelampus biomass was 4.96±0.52 SE g dry wt/m2 on the restored impounded marsh and 6.96±0.52 SE g dry wt/m2 on the unimpounded marsh. On the two marshes, snail density and biomass varied in relation to plant cover and other factors.
The density and biomass ofGeukensia at the edge of the marsh were comparable on the restored impounded and unimpounded marshes. Mean mussel densities ranged
from 80 to 240/m2 and mean mussel biomass varied from 24.8–64.8 g dry wt/m2 in different low marsh areas. In contrast, below the impoundment dike, meanGeukensia density was 1100±96.4 SE/m2 and meanGeukensia biomass was 303.6±33.28 SE g dry wt/m2. A consideration of all available evidence leads to the conclusion that the impounded marsh is in an advanced phase of restoration. 相似文献