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91.
针对人因可靠性分析中的数据匮乏问题,在技能-规则-知识(SRK)模型的基础上建立层次化的人因可靠性数据分类体系,其中包括人因失误模式和人因失误影响因素。结合对一些实际人因失误数据的考察,以及可控实验,确定人因可靠性数据库中基准人因失误概率。在人因数据外推系统中,使用层次分析法(AHP)来定量评价人因失误所处的情境的等级,并使用概率方法将基准人因失误概率与情境进行叠加,从而得到人因失误概率。人因数据库有助于人因可靠性数据的搜集和分析,形式化的外推方法减少了对主观因素的依赖。  相似文献   
92.
The Convention on Biological Diversity has catalyzed worldwide awareness of threats to biological diversity and stimulated global conservation strategies. These have led to national and international legislation and have generated debate about the most effective conservation actions. Under the EU Habitats Directive, all member states are obliged to establish a system for strict protection of species listed in Annex IV(a), which includes all bats. In England, this obligation has resulted in legislation that allows for derogation from strict protection under license, provided activities are undertaken to mitigate any potential negative effects on bat numbers. We used an evidence‐based approach to assess the cost‐effectiveness of mitigation strategies and the English bat‐derogation licensing process as a whole. We analyzed data from 389 bat derogation licenses issued in England from 2003 to 2005 relating to 1776 roosts and 15 species to determine the nature and extent of development and mitigation activities and their effects on bats. Overall the effects of licensed activities on roosts were negative. Despite the level of protection afforded to bats, the majority (68%) of roosts for which derogation licenses were issued were destroyed. There were species‐specific differences in the probability of roosts being destroyed, and impacts on roosts did not reflect a species’ conservation status. Information provided by licensees was inadequate and inconsistent. Most licensees (67%) failed to submit postdevelopment reports, and postdevelopment monitoring was conducted at only 19% of sites. Despite a minimum of £4.13 million spent on mitigation structures for bats from 2003 to 2005, it was unclear whether the licensing process meets EU obligations. On the basis of our results, we believe there is a need to overhaul the licensing process, to establish a comprehensive, standardized postdevelopment monitoring system, and to demonstrate that mitigation is commensurate with Britain's legal obligations. Mitigando el Efecto del Desarrollo sobre los Murciélagos en Inglaterra con Licencias de Derogación  相似文献   
93.
人粪便中温好氧堆肥过程的有机物降解特性研究   总被引:2,自引:1,他引:1  
白帆  王晓昌 《环境工程学报》2011,5(8):1863-1866
利用密闭式小型堆肥反应器,以锯末作为堆肥载体,采用批量反应的操作方式,在35℃的温控条件下进行了人粪便的中温好氧堆肥实验。结果表明,在14 d的堆肥反应周期内,粪便中以COD为参数的有机物去除率可达到70%左右,且在10~12 d内基本完成有机物降解。在中温条件下,堆体容易保持适宜的含水率和pH值,维持适宜微生物繁殖生长的条件。运用磷脂法进行堆肥过程中微生物总量的分析,表明在一个堆肥周期内,微生物经历了环境适应期、稳定增殖期、生物量下降期等3个阶段,这一微生物繁衍规律与有机物的去除密切相关。与高温堆肥相比,中温堆肥能够减少设备加热的能量消耗,是缺水地区人粪便处置的可选方法之一。  相似文献   
94.
乡村人居环境:人居环境科学研究的新领域   总被引:5,自引:0,他引:5  
乡村人居环境是人居环境科学的重要构成部分,随着城市化的快速推进,乡村人居环境日益恶化.人居环境科学研究存在明显缺陷,即人居环境研究的"城市主义"倾向明显,忽视了乡村人居环境研究.分析了开展乡村人居环境研究的重要性和紧迫性,评述了国内外的相关研究成果,提出了乡村人居环境研究的多维视角,即基于农户空间行为的乡村人居环境研究、乡村人居环境的地域文化与发展模式研究、乡村人居环境与空间规划研究、基于"3S"技术的乡村人居环境研究、乡村人居环境的系统理论与发展战略研究.  相似文献   
95.
The objective of the study was to evaluate the potential risk of DNA damage due to exposure to a mixture of the most widely used pesticides, namely endosulfan, chlorpyriphos and thiram at an environmentally relevant concentration (5 μM each) and the DNA protective capacity of sulforaphane (SFN) (10–30 μg/mL). DNA damage in human lymphocytes was ascertained with Single Cell Gel Electrophoresis (SCGE), also called Comet Assay. For positive control, H2O2 at 100 mM was used. The pesticide mixture produced DNA damage at the concentration used in the lymphocytes. SFN was able to offer a statistically significant (P < 0.01), concentration-dependant protection to DNA damage between 10–20 μg/mL in both the pre-incubation and co-incubation strategies. The results indicate that exposure to low levels of these pesticide mixtures can induce DNA damage, and the presence of SFN in diet may reduce the incidence of genetic damage, especially in farm workers. However, it is not clear whether SFN is involved in quenching of the free radicals generated by the pesticide mixture or it is involved in DNA repair mechanism.  相似文献   
96.
I offer a very qualified argument to the effect that rights are grounded in a certain sort of prejudice that privileges individualistic and perhaps masculinist ways of thinking about moral life. I also propose that we look carefully at other conceptions of social ontology and moral life, including the much discussed care conception.  相似文献   
97.
通过对四川省科技人力资源的潜力、结构变化的分析,提出建立统一规范的科技人才培养经费投入政策,加强科技人才资源的再开发,不拘一格引进科技人才,建立四川省科技人力资源监测系统等对策。  相似文献   
98.
张大任 《四川环境》1993,12(3):66-70
作者将自然运动与人类活动、生态环境与气候结合起来研究,求索洪旱灾害之谜,着重探讨了其中多种生态环境因素。由大灾后的反思,找出灾害加剧的人为原因是:人中激增、生态危机、水利失修等,提出必须加强防灾减灾的对策研究。  相似文献   
99.
This work validated a burial protocol for in situ testing and presents a robust, repeatable and time-saving technique to measure degraded areas in the sample, i.e. an image analysis method. 1440 specimens of degraded samples have been compiled in a data base. To this end, twenty samples presenting different levels of biodegradability (i.e. PHBV/HV, PLA, PCL, PCL-Starch, paper, PE, PE-Starch) were buried at 4 different locations and then disinterred at 4, 6, 9, 12, 18, and 24-month intervals. The biodegradation levels of these samples were determined by computing weight and area loss. Weight loss was measured after careful cleaning, whereas area loss was quantified using image analysis. Image analysis gives reliable information on visual pollution while only requiring a rudimentary and thus quicker cleaning of the samples.  相似文献   
100.
泥石流与人类经济活动   总被引:10,自引:1,他引:9  
山地是泥石流与人类共存的环境,泥石流作用于山地环境,强烈地影响人类经济活动:人类经济活动也作用于山地环境,强烈地影响泥石流。泥石流对山地环境的危害,主要为破坏地表、破坏生态系统和淤堵江河;泥石流对人类及其经济活动的危害,主要为破坏城镇,村庄,工矿,交通水利水电工程,农田和人类自身的安全。泥石流危害的结果,能导致山地坡面破碎化、沟口沙石化、河床宽浅化和植被逆向演替化,以及耕地贫瘠化、经济发展滞后化和  相似文献   
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