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61.
航空人为差错事故/事件分析(ECAR)模型研究   总被引:2,自引:0,他引:2  
为深入研究航空人为差错事故/事件的影响因素,以人为差错相关理论为基础,对比分析几种典型的人为差错分析模型;通过借鉴ECCAIRS分析框架,并在基元事件分析(EEAM)逻辑和CCAR396部的分类方法基础上,构建航空人为差错事故/事件分析(ECAR)模型,它从事件层、描述层、原因层和组织因素与改进建议层,分析航空事故和不安全事件的人为差错。此外,还将组织因素概念引入该模型。  相似文献   
62.
Environmental Reporting by the Fortune 50 Firms   总被引:1,自引:0,他引:1  
/ The extent and use of industry-reported environmental data are increasing, warranting an in-depth analysis of this information. This paper reviews the environmental reporting guidelines issued by several business and nonprofit organizations and evaluates the environmental reports published by the Fortune 50 companies, half of which publish reports. After describing the history of environmental reporting and the content of the guidelines, a comparative evaluation is made to indicate the types of companies producing reports, the topics reported, the intended audiences, the scope and depth of the material reported, and the effectiveness of the reports as communication devices. These reports are mechanisms to enhance a firm's image, public relations, and marketing and are aimed largely at concerned individuals, affected communities, and investors. Significant differences in the content and the depth of reports are seen as firms report on topics that are perceived by the public as high risks. The most complete reports are published by industries with poor or controversial public images, e.g., the chemical and timber industries. Still, no report provided information that was sufficient for comprehensive or comparative analyses of environmental performance. Recommendations are provided to increase the quality and effectiveness of environmental reporting.KEY WORDS: Communication; Environmental management; Performance reporting; Reporting; Stakeholder  相似文献   
63.
简要论述了江苏省地震速报的历史、现状及计算机技术在地震速报中的重要作用。介绍了FDSP的功能、采用的主要技术以及在本次南黄海6.1级地震中的应用  相似文献   
64.
International declarations and charters have been produced to encourage and support higher education institutions (HEIs) to address their environmental responsibilities. This paper discusses the results of a critical examination of a range of international HEIs that have signed the global environmental Talloires Declaration. It also assesses the Talloires Secretariat (University Leaders for a Sustainable Future, ULSF) and the extent to which this has been a primary stimulus. An international survey was undertaken and the results presented in a discursive format in order to highlight key driving forces, barriers, and opportunities for environmental responsibility in HEIs. Analysis reveals that they occur on two distinct and evolving levels: the macro national framework level and the micro institutional framework level. Survey responses revealed that none of the HEIs have an embedded institutional environmental culture and most did not have all the micro institutional mechanisms in place for an integrated university-wide environmental response. Many of the institutional barriers to environmental responsibility occurred as a result of this lack of strategy. The most significant institutional opportunity cited was enthusiastic individuals, particularly those at senior management or directorate level, and these individuals were found to be a key driving force. Results also showed that environmental reporting along the lines developed by the private sector is a flexible mechanism that can stimulate progress internally and externally and can be cost effectively disseminated via the World Wide Web. Moreover the survey results indicate that ULSF is not currently a primary stimulus for institution wide action.  相似文献   
65.
我国与国际空气污染指数系统的比较   总被引:6,自引:0,他引:6  
通过对中国内地、中国香港、韩国和美国的空气污染指数系统进行比较,结果发现,中国内地API系统在污染分级描述、数据的时空代表性、污染物种类和污染分级的浓度限值等方面与其他系统存在很大的差别.同时,以珠三角区域空气质量监控网的天湖、万顷沙和荃湾3个站点2005~2007年的数据为依据,评价了在中国现行的评级系统中加入O3和PM2.5对API水平和首要污染物的影响,并讨论了采用不同的污染物浓度限值对臭氧和颗粒物分指数的影响,最后从科学研究和环境管理的角度论述了修订我国API评级系统的必要性.  相似文献   
66.
中国空气污染指数变化特征及影响因素分析   总被引:21,自引:6,他引:15  
以2001~2010年我国42个城市逐日空气污染指数、主要污染因子、空气质量级别和空气质量状况资料为基础,分析了近10 a我国空气质量的变化特征.结果表明,我国城市大气受燃煤影响较为严重,可吸入颗粒物为主要污染因子,空气质量状况以优、良和轻微污染居多;空气质量季节变化明显,冬季空气污染最严重,夏季最轻;从年际变化看,空气质量表现出逐年好转趋势;城市大气环境质量在区域上存在显著差异,表现为由南到北、从沿海到内陆逐渐变差的趋势.对空气污染影响因素的分析表明,局地污染和西北地区沙尘传输造成的自然降尘是我国城市空气质量的主要污染源;气象要素对大气污染物有制约关系,空气污染指数与降水量、风速、逆温线性相关;地形的空间差异影响着气象条件的分布,进而对空气质量的空间变化产生影响;人类活动对城市空气质量也存在一定的影响,且具有双重作用.  相似文献   
67.
A major objective of analyzing multiple year tag return data in fisheries is to estimate fishing and natural mortality rates which may vary by age class and calendar year. To do this one needs to be able to estimate the reporting rates for the tags recovered. Some fisheries such as that for Southern Bluefin Tuna (Thunnus maccoyii) have multiple components with potentially different reporting rates for the tag returns. In this paper we develop a general model for multi-cohort, multi-year tag return analyses where there are multiple components to the fishery with potentially different reporting rates. We require the assumption that one component has a reporting rate of 100% (i.e., this could be the component of a boat based fishery where scientific observers are present). We show further how it is possible to partition the overall likelihood developed into two conditionally independent components. The first component of the likelihood is the standard multinomial likelihood that allows estimation of fishing and natural mortality rates. It uses the tag return matrix summed over all the components of the fishery. It requires an average reporting rate for the tag returns (where the average reporting rate is a weighted average of the individual reporting rates of the different components). The second component is also multinomial for the individual component tag returns and allows us to estimate individual component reporting rates. However, this requires that we augment our second component tag return likelihood with a catch data likelihood for the corresponding components. The methodology is illustrated on some Southern Bluefin Tuna tagging and catch data. We also discuss important model assumptions and give suggestions for future research including the integration of tag-return and catch at age data analyses.  相似文献   
68.
Developing a transparent,accurate greenhouse gas (GHG) emissionsinventory is the first step toward buildingan effective GHG management system. Todate, GHG inventories have been conductedprimarily at national levels. Theinternationally accepted inventorymethodology developed by theIntergovernmental Panel on Climate Change(IPCC) is oriented to countrywideinventories. The electricity company RAOUESR is the largest single corporateemitter of GHG in the Russian Federation. The company is responsible for about 1/3 ofRussia's CO2 emissions; RAO's fossil fuelemissions are comparable to the fossil fuelemissions of the United Kingdom. The GHGinventory prepared by RAO is the first suchcorporate emissions inventory undertaken ina non-OECD country. In this article wepresent a detailed independent examinationof the methodology RAO applied for theinventory. We identify the most importantsources of uncertainty and we estimate theuncertainty. The main conclusion of theindependent review is that the methodologyutilized by RAO and the informationsupporting the methodology are reliable andpresent a reasonably accurate company-widepicture of RAO's CO2 emissions. The shareof other greenhouse gases is negligiblysmall and we did not focus on this fractionof RAO's GHG emissions. As a next step, RAOmay wish to conduct more precisefacility-by-facility inventories in orderto create a robust GHG emission managementsystem.  相似文献   
69.
利用博罗县城自动监测站2015年的环境空气自动监测数据,分析了实施《环境空气质量标准》(GB3095-2012)对博罗县城空气质量评价的影响.研究发现,若采用新标准,博罗县城空气中PM2.5和O3将出现不同程度的超标,达标率从99.4%下降到88.5%;PM2.5和O3的纳入是导致空气质量达标率下降的最主要原因,NO2标准的收严和CO的纳入未对博罗县城空气质量评价造成影响.  相似文献   
70.
基于GA-ANN改进的空气质量预测模型   总被引:2,自引:0,他引:2       下载免费PDF全文
赵宏  刘爱霞  王恺  白志鹏 《环境科学研究》2009,22(11):1276-1281
基于人工神经网络的空气质量预测模型优于传统的逐步回归模型,但由于性能差异不明显而较少在空气质量预报中应用. 设计了将遗传算法和神经网络算法相结合的基于GA-ANN的空气质量预测模型,并利用天津市2003—2007年气象和污染物监测资料对该模型进行验证. 对2007年全年的ρ(SO2),ρ(NO2)和ρ(PM10)进行预测,预测值与实测值的相关系数分别为0.899 6,0.828 3和0.600 0. 与一般的人工神经网络预测模型相比较,GA-ANN模型将空气质量等级预报的准确率从77.57%提高到79.67%. GA-ANN模型可结合其他方法进行日常空气质量预报.   相似文献   
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