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101.
作为应急管理中的主要工作内容,应急决策在整个应急管理工作中具有战略意义,为了对危机情境下的应急决策主体进行聚类分析,定量计算不同决策主体之间相应决策文本的区别。借鉴最长公共子序列模型(LCS)的原理,从决策文本中提取主题词,根据决策文本的特点将其分为“目标”和“行动”2级,结合样本总体确定替换矩阵、空位罚分规则和目标函数,构建高层应急决策文本相似性比对分析模型;运用Needleman Wunsch算法对该模型进行求解;通过对得到的地震情景下的高层应急决策文本的分析,证明模型的有效性和可行性;为了避免序列长度差过大对聚类分析的结果影响,在此基础上提出相对相似性得分的概念,并通过与VSM算法得到的结果进行比较,证明该模型在应急决策文本相似性分析中的优越性。  相似文献   
102.
生物修复技术削减途经土壤中的硝态氮是一种环境友好且生态效益高的方法。构建了含不同填料的A (土壤) 、B (土壤+木屑) 、C (土壤+木屑+蜡样芽孢杆菌) 、D (土壤+木屑+土著反硝化菌) 4种渗透反应柱,将从土壤填料中筛选出单株具有良好反硝化性能的土著反硝化菌 (Pseudomonas sp. P10) 和来源于湖泊底泥的反硝化菌蜡样芽孢杆菌分别接种至渗透反应柱,探究土著反硝化菌对巢湖流域同源水稻田土壤填充渗透反应柱脱氮效果的影响。结果表明,向反应柱中接种土著反硝化菌Pseudomonas sp. P10可缩短反应柱去除NO3-N的启动时间,填料为土壤与木屑的B柱对NO3-N去除率可达96.05%。 接种土著反硝化菌的D柱出现了NH4+-N积累现象, B、C、D柱中积累的[NO2-N]均低于2.4 mg·L−1。在30 mg·L−1和50 mg·L−1的NO3-N进水条件下,各反应柱对TN去除率为50%~70%。各反应柱出水TOC符合水质标准。接种土著反硝化菌的D柱中优势菌种为Pseudomonas属细菌,C柱中接种的蜡样芽孢杆菌并没能成功地与原有微生物群落竞争。接种土著反硝化菌对土壤反硝化能力有一定强化作用,但随着时间的延长,在充足可利用碳源条件下,没有接种微生物的反应柱更具有反硝化脱氮优势。该研究结果可为提升土壤对外源氮素的削减和湖泊氮素污染的控制提供参考,也为湖库淤积物的资源化利用及治污情况下生态系统的稳态维持和可持续的系统动力学提供依据。  相似文献   
103.
Diving practices of a group of indigenous people living on Thailand’s west coast were investigated. Village chiefs were first interviewed using a questionnaire. Three hundred and forty-two active divers were then interviewed by health care workers using a second questionnaire. Field observation was used to further develop information and confirm diving practices. Divers in 6 villages, whose basic means of making a living is from diving for marine products such as fish and shellfish, have diving patterns that put them at substantial risk of decompression illness. Breathing air from a primitive compressor through approximately 100 m of air hose, these divers have long bottom times coupled with short surface intervals. Forty-six point two percent of the divers indicated that they would not make a stop during ascent from a long deep dive (40 m for 30 min). When comparing their previous day of diving to the U.S. Navy Standard Air Decompression Table (U.S. Navy, 1993), 72.1% exceeded the no-decompression limits set by the tables. Diving patterns point to a need for more in-depth research into the diving patterns of this indigenous group. Future research should include the use of dive logging devices to record depths and times. There is also a need to provide divers with information and training to reinforce positive practices and strengthen knowledge of the risks associated with their current diving practices.  相似文献   
104.
Despite large investments that have gone into meeting the challenges of effective waste management in urban Nigeria, there is little evidence that such efforts are having their expected impacts. Consequently, much attention has been drawn to the need to evolve more sustainable waste management strategies. Drawing on data from in-depth interviews among the Ngwa of southeastern Nigeria, some useful indigenous solid and liquid waste management techniques, in the search for solutions to the current waste management crisis in urban Nigeria, have become evident. These indigenous techniques and practices, which include ingenious and careful waste segregation and sorting, selective burning and burying, composting and conversion, etc., offer scope for meeting the challenges and addressing the limitations of current waste management in urban areas, especially if they are supported by appropriate inputs from modern technology.  相似文献   
105.
传统的“唯GDP ”的经济发展方式成为中国未来经济可持续发展的桎梏,转变发展方式,提高经济增长质量,倡导共享式、包容性增长成为中国经济发展的新主题,而这种发展模式的基本导向就是促进“人的发展”.基于这样一个视角,本文依据经济增长质量提高的要求,从人的素质、人的福利、人的保障、人的迁移4个方面构建综合评价指标体系,对改革开放30年人的发展程度进行了测度与评价.评价结果显示:随着经济不断发展,30年间中国人的发展状况得到明显提高,但是人的发展指数以及人的素质指数、人的福利指数、人的保障指数、人的迁移指数、经济状况指数、资源环境指数仍需不断改善.未来中国在提高增长质量的过程中要促进人的发展,强调经济发展与人的发展的协调,树立“以人为本”的发展理念,着眼于人性,重视人的存在、人的价值、人的意义,建立促进人的素质和能力提升的机制和体制,确定以“富民”为目标的经济发展道路,实现人的发展与生态环境协调发展的有机统一.  相似文献   
106.
Abstract:  We compared and integrated marine protected areas proposed through community and scientific assessments in 2 regions of British Columbia, Canada. The community priorities were identified during individual and group interviews with knowledgeable resource users. The scientific priorities were developed with abiotic and biotic data in Marxan, a decision-support tool. The resulting maps of community-based and science-based priorities were very similar for the inshore areas, which lent credibility to both approaches. The resource users thought the science-based maps were fairly good at highlighting areas important for conservation, but preferred the scenarios that integrated the 2 maps to either constituent map. Incorporating spatial variation in human impacts on the marine areas and commercial fishing, which are both costs of protection, into our Marxan analyses led to scenarios that were different from either constituent map. Our results show the value of integrating community-based and science-based approaches in conservation planning to achieve community acceptance and conservation utility. They also reveal that people's assessments on the basis of their traditional ecological knowledge may serve as a reasonable proxy for scientific approaches in selecting areas of ecological value.  相似文献   
107.
失地农民在征地过程中没有得到合理补偿和妥善安置,影响农村经济发展和社会稳定.妥善安置失地农民,解决失地农民的后顾之忧,除控制征地规模,对现行征地制度、利益分配机制进行改革外,为失地农民的长远生计设计更合理的制度性保障已迫在眉睫.  相似文献   
108.
在近七八十年里,生态环境脆弱的陇东地区由于人口增加引起乱砍滥伐、过度放牧、陡坡开垦造成的水土流失和引起大量开垦坡地,广种薄收,形成“越穷越垦、越垦越穷”的恶性循环等等,出现了一系列人地矛盾.随着植树造林,退耕还林,禁止放牧等一系列政策措施的实施和社会经济的快速发展,使得这一矛盾得到了一定程度的缓解,可今后怎样保持和继续深化以及怎样在环境可承载下发展经济和提高人民的生活水平是我们要思考的问题.从环境变化的几个方面进行讨论并得出一些存在的问题及建议.  相似文献   
109.
运用法学原理论证只有建筑施工单位是建筑施工噪声环境行政管理相对人,阐明现行申报制度、排污收费制度和“污染者负担原则”在建筑施工噪声管理中的法律适用问题。  相似文献   
110.
Large-scale infrastructural developments in rural areas often impose significant direct and indirect impacts on environment and people. The Three Gorges Project to dam the Yangtze River in China will create a huge reservoir, inundate farmlands and villages, and incur large-scale resettlement. The concurrent de-farming program to reforest marginal farmlands on steep slopes imposes additional stresses on local people. This study evaluates the ecological and economic adjustments in rural areas affected by both projects, and explores villagers’ knowledge, attitudes, perceptions, and expectations vis-à-vis the drastic changes. Eleven villages in Yunyang County in Sichuan Province, stratified into three zones based on topography and agriculture, were assessed by field studies, questionnaire surveys, maps, satellite imagery, and census and government reports. Multiple regressions identified predictors for 17 dependent variables. Spatial variations in the difficult terrain imposed zone-differentiated agricultural constraints, ecological impacts, and human responses. The dominant farming population—mainly young adults working as migrant laborers in cities—has adopted some nonagricultural work to supplement incomes. Expected per-capita standardized farmland (SF) exceeded threshold SF, which surpasses existing SF. Motivations to reclaim more farmlands, de-farm marginal lands, and become migrant laborers were explained by different multiple-regression predictors. Reduction in farmland stock by inundation and de-farming, aggravated by unwillingness towards nonlocal resettlement, would impose ecological pressures and stimulate demands for nonfarming incomes. Common anticipation of better future income and occupation has been subdued by unfavorable feedbacks from early relocatees. Future environmental and landscape changes are hinged upon changing human responses. Government policies could be informed by research findings to match economic, ecological, and social realities.  相似文献   
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