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331.
332.
The fundamental way of satisfying the basic needs of human development is to secure the basic needs,limit luxurious and wasteful emissions,and ensure the fulfillment of climate targets,so as to achieve intra-and intergenerational equity.In this paper,the author discusses and analyzes a series of challenges that the development has to face,such as poverty elimination,urbanization,and industrialization,and the problems of increased consumption that is brought about by the improvement of living standards;the author distinguishes the stock emission,which does not need annual updating,and the flow emission of regular consumption;the author also defines the standards of energy consumption and carbon emissions that can meet the basic needs.On this basis,the author proposes the concept and method of carbon budget,compares this method with other means,and in particular,studies and analyzes the implications of international equity and sustainability of carbon budget as part of the international climate regime design.  相似文献   
333.
登沙河流域水质监测断面优化研究   总被引:1,自引:0,他引:1  
基于大连市登沙河监测断面的水质数据,采用系统聚类法、模糊聚类法和物元分析法进行优化,筛选代表性断面.结果表明,优化后的监测断面个数减少了40%,相关性较高的相邻断面个数由优化前的71%减少为54%,优化前、后的样本方差齐且均值无显著性差异.优化后的监测断面在显著提高效率的同时也确保了数据的代表性,使得断面重复布设情况得...  相似文献   
334.
Around the globe, human behavior and ecosystem health have been extensively and sometimes severely affected by the unprecedented COVID-19 pandemic. Most efforts to study these complex and heterogenous effects to date have focused on public health and economics. Some studies have evaluated the pandemic’s influences on the environment, but often on a single aspect such as air or water pollution. The related research opportunities are relatively rare, and the approaches are unique in multiple aspects and mostly retrospective. Here, we focus on the diverse research opportunities in disease ecology and ecosystem sustainability related to the (intermittent) lockdowns that drastically reduced human activities. We discuss several key knowledge gaps and questions to address amid the ongoing pandemic. In principle, the common knowledge accumulated from invasion biology could also be effectively applied to COVID-19, and the findings could offer much-needed information for future pandemic prevention and management.  相似文献   
335.
336.
Farmworkers' children may have increased pesticide exposure through dermal absorption and non-dietary ingestion, routes that are difficult to measure and model. The Cumulative Aggregate Simulation of Exposure (CASE) model, integrates the complexity of human behavior and variability of exposure processes by combining micro-level activity time series (MLATS) and mechanistic exposure equations. CASE was used to estimate residential non-dietary organophosphate pesticide exposure (i.e., inhalation, dermal, and non-dietary ingestion) to California farmworker children and evaluate the micro-activity approach. MLATS collected from children and distributions developed from pesticide measurements in farmworkers' residences served as inputs. While estimated diazinon exposure was greater for inhalation, chlorpyrifos exposure was greater for the other routes. Greater variability existed between children (σB2 = 0.22–0.39) than within each child's simulations (σW2 = 0.01–0.02) for dermal and non-dietary ingestion. Dermal exposure simulations were not significantly different than measured values from dosimeters worn by the children. Non-dietary ingestion exposure estimates were comparable to duplicate diet measurements, indicating this route may contribute substantially to aggregate exposure. The results suggest the importance of the micro-activity approach for estimating non-dietary exposure. Other methods may underestimate exposure via these routes. Model simulations can be used to identify at-risk children and target intervention strategies.  相似文献   
337.
将影响水资源可持续开发利用的主要评价指标组成模糊物元,同时各开发利用阶段作为物元的对象,以各项评价指标及其相应的模糊量值构造复合模糊物元,运用层级分析法(AHP)确定各评价指标的权重,最后计算其欧化距离相似贴近度.通过广东省水资源可持续开发利用评价验证了该分析方法的科学性和有效性.  相似文献   
338.
A simple and straightforward method for simultaneous determination of residues of 13 pesticides in honey samples (acrinathrin, bifenthrin, bromopropylate, cyhalothrin-lambda, cypermethrin, chlorfenvinphos, chlorpyrifos, coumaphos, deltamethrin, fluvalinate-tau, malathion, permethrin and tetradifon) from different pesticide classes has been developed and validated. The analytical method provides dissolution of honey in water and an extraction of pesticide residues by n-Hexane followed by clean-up on a Florisil SPE column. The extract was evaporated and taken up by a solution of an injection internal standard (I-IS), ethion, and finally analyzed by capillary gas chromatography with electron capture detection (GC-µECD). Identification for qualitative purpose was conducted by gas chromatography with triple quadrupole mass spectrometer (GC-MS/MS). A matrix-matched calibration curve was performed for quantitative purposes by plotting the area ratio (analyte/I-IS) against concentration using a GC-µECD instrument. According to document No. SANCO/12571/2013, the method was validated by testing the following parameters: linearity, matrix effect, specificity, precision, trueness (bias) and measurement uncertainty. The analytical process was validated analyzing blank honey samples spiked at levels equal to and greater than 0.010 mg/kg (limit of quantification). All parameters were satisfactorily compared with the values established by document No. SANCO/12571/2013. The analytical performance was verified by participating in eight multi-residue proficiency tests organized by BIPEA, obtaining satisfactory z-scores in all 70 determinations. Measurement uncertainty was estimated according to the top-down approaches described in Appendix C of the SANCO document using the within-laboratory reproducibility relative standard deviation combined with laboratory bias using the proficiency test data.  相似文献   
339.
随着经济全球化及网络通讯技术进步,服务外包已成为重塑世界产业格局的重要力量,其相关研究引起了学者的广泛关注。主要对服务外包产业发展规律和效应评估的相关研究进行综述。首先介绍了服务外包产生的主要理论观点,并梳理其演进过程及空间分布的研究进展;其次讨论服务外包效应评估的研究内容,其中发包国效应围绕就业、工资、生产力3个方面展开,承接国效应从经济、社会、技术外溢3个角度分析;第三,从理论和实证两个层面对效应评估方法进行了总结,重点基于投入产出表数据、研究报告数据及贸易数据归纳了测度外包水平的不同方法;在综合评述的基础上,展望了未来的研究趋向  相似文献   
340.
以阿马蒂亚.森的权利分析方法作为主要的理论框架,在参考脆弱性分析和社会资产分析的基础上,将外部干预和农户的社会资本加入上述权利分析框架,用以解释农户灾后恢复的差异。研究发现,资源禀赋和交换权利的差异造成了农户灾后恢复的差异:具有较好资源禀赋和交换权利的农户能够迅速跳出短期贫困的陷阱,恢复生计;而资源禀赋和交换权利较差的农户则无法迅速跳出地震灾害所造成的短期贫困陷阱,恢复生计。  相似文献   
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