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41.
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
42.
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
43.
Pryor SC Larsen SE Sørensen LL Barthelmie RJ 《Environmental pollution (Barking, Essex : 1987)》2008,152(3):667-678
This paper reports a study designed to test, evaluate and compare micro-meteorological methods for determining the particle number flux above forest canopies. Half-hour average particle number fluxes above a representative broad-leaved forest in Denmark derived using eddy covariance range from -7x10(7) m(-2) s(-1) (1st percentile) to 5x10(7) m(-2) s(-1) (99th percentile), and have a median value of -1.6x10(6) m(-2) s(-1). The statistical uncertainties associated with the particle number flux estimates are larger than those for momentum fluxes and imply that in this data set approximately half of the particle number fluxes are not statistically different to zero. Particle number fluxes from relaxed eddy accumulation (REA) and eddy covariance are highly correlated and of almost identical magnitude. Flux estimates from the co-spectral and dissipation methods are also correlated with those from eddy covariance but exhibit higher absolute magnitude of fluxes. 相似文献
44.
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
45.
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
46.
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
47.
Paige Brown Jarreau Amy Reynolds 《Environmental Communication: A Journal of Nature and Culture》2017,11(2):143-165
This mixed-method case study of environmental communication best practices in Louisiana, USA, identifies trends and approaches as informed by environmental psychology. The results provide key insights for environmental communicators, especially communicators in coastal regions. In-depth interviews with both environmental psychologists and environmental communicators showed that both groups emphasized knowing the audience, telling local stories, building relationships with target audiences and targeted messaging. Both psychologists and communicators also frequently mentioned general messaging concerns of source credibility, avoiding controversial terms and talking about issues, impacts and solutions to which the target audience can relate. A representative survey revealed that Louisiana residents are most interested in hearing about how environmental issues such as climate change, coastal land loss and flooding are affecting their own communities. This finding supports the idea that environmental communicators could do a better job tapping into strong place attachment and sense of community among coastal residents to promote action. 相似文献
48.
49.
Effectiveness of Africa's tropical protected areas for maintaining forest cover 总被引:1,自引:0,他引:1 下载免费PDF全文
The effectiveness of parks for forest conservation is widely debated in Africa, where increasing human pressure, insufficient funding, and lack of management capacity frequently place significant demands on forests. Tropical forests house a substantial portion of the world's remaining biodiversity and are heavily affected by anthropogenic activity. We analyzed park effectiveness at the individual (224 parks) and national (23 countries) level across Africa by comparing the extent of forest loss (as a proxy for deforestation) inside parks to matched unprotected control sites. Although significant geographical variation existed among parks, the majority of African parks had significantly less forest loss within their boundaries (e.g., Mahale Park had 34 times less forest loss within its boundary) than control sites. Accessibility was a significant driver of forest loss. Relatively inaccessible areas had a higher probability (odds ratio >1, p < 0.001) of forest loss but only in ineffective parks, and relatively accessible areas had a higher probability of forest loss but only in effective parks. Smaller parks less effectively prevented forest loss inside park boundaries than larger parks (T = ?2.32, p < 0.05), and older parks less effectively prevented forest loss inside park boundaries than younger parks (F2,154 = ?4.11, p < 0.001). Our analyses, the first individual and national assessment of park effectiveness across Africa, demonstrated the complexity of factors (such as geographical variation, accessibility, and park size and age) influencing the ability of a park to curb forest loss within its boundaries. 相似文献
50.
A Comprehensive Python Toolkit for Accessing High‐Throughput Computing to Support Large Hydrologic Modeling Tasks 下载免费PDF全文
Scott D. Christensen Nathan R. Swain Norman L. Jones E. James Nelson Alan D. Snow Herman G. Dolder 《Journal of the American Water Resources Association》2017,53(2):333-343
The National Flood Interoperability Experiment (NFIE) was an undertaking that initiated a transformation in national hydrologic forecasting by providing streamflow forecasts at high spatial resolution over the whole country. This type of large‐scale, high‐resolution hydrologic modeling requires flexible and scalable tools to handle the resulting computational loads. While high‐throughput computing (HTC) and cloud computing provide an ideal resource for large‐scale modeling because they are cost‐effective and highly scalable, nevertheless, using these tools requires specialized training that is not always common for hydrologists and engineers. In an effort to facilitate the use of HTC resources the National Science Foundation (NSF) funded project, CI‐WATER, has developed a set of Python tools that can automate the tasks of provisioning and configuring an HTC environment in the cloud, and creating and submitting jobs to that environment. These tools are packaged into two Python libraries: CondorPy and TethysCluster. Together these libraries provide a comprehensive toolkit for accessing HTC to support hydrologic modeling. Two use cases are described to demonstrate the use of the toolkit, including a web app that was used to support the NFIE national‐scale modeling. 相似文献