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目前全国水资源优化配置的研究依然停留在借鉴和摸索阶段,对水资源优化配置的主要任务、遵循的原则、配置方案以及未来的发展方向进行了探讨. 相似文献
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Cobalt is obtained mainly as a byproduct of the mining and metallurgical processing of copper and nickel. The amount of minable
cobalt has a characteristic supply limit, which is dependent upon demand for copper and nickel. It is considered that cobalt
consumption will be affected by the amount mined in the near future, because world demand has been gradually increasing, while
the production from copper sulfide ores in Zaire and Zambia, major producing countries, has decreased for political, economical
and technological reasons. The world demand for cobalt has surpassed the world mine production, and cobalt sales from the
National Defense Stockpile of the United States and exports from Russia and cobalt recovered from stockpiled intermediates
contributed to the supply in 1994. It is concluded, from a statistical point of view, that this trend of shortage and high
prices for cobalt will continue in the near future. 相似文献
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INVESTIGATION OF STATUS AND DEMAND ON PUBLIC SERVICE OF EARTHQUAKE DISASTER MITIGATION IN CHINA
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In order to make a comprehensive and systematic evaluation of the status and demands of public service of earthquake disaster mitigation, we launched an investigation with Social Opinion Polling Center of National Bureau of Statistics on the current situation of public service of earthquake disaster mitigation and the demands for it in 2018. The investigation was conducted for 18~75-year-old residents for both urban and rural areas in 31 provinces of China mainland using the Computer Assisted Telephone Interview(CATI)method and 20 078 valid samples were received in total. The questionnaire mainly includes two parts: the current situation assessment and the demand survey. The assessment of public service status consists of five indicators: earthquake emergency drill, knowledge publicity of earthquake prevention and disaster reduction, acquisition of earthquake information, reliability of information released by earthquake agencies, and overall satisfaction. The results indicate that only 27.4% of public have participated the earthquake emergency drill, and 73.5% of public have learned some knowledge about earthquake prevention and disaster reduction in different level. It shows that rural residents have a lower level of scientific knowledge of earthquake disaster mitigation although the rural residents have a higher level of satisfaction. Meanwhile, 82.9% of the public are very concerned about earthquake-related information, and the earthquake information acquisition convenience score is 81.51 points(the full score is 100 points). At present, TV is still the most popular way to obtain the earthquake-related information, besides that, network and the new media app such as Wechat and Weibo play a more and more important role. In terms of the reliability of official information published by the earthquake administration, the score is 83.69 points which indicates that the public tend to believe in official departments. Furthermore, the degree of satisfaction evaluation of public service of earthquake disaster mitigation is marked 76.44 points which shows that there is still much room for improvement. The more educated the public, the less satisfied they are with the public service of earthquake prevention and disaster reduction. The results also show that 51.81% of the public are willing to obtain earthquake warning information at their own expense. As for the demand, the most expectative services for the public are post-earthquake rescue and reconstruction, earthquake warning, and house earthquake resilience test. The results of the investigation may provide some reference for the government to provide better services of earthquake disaster mitigation and to make scientific knowledge popularization in a more scientific way. 相似文献
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基于“S”规律的中国钢需求预测 总被引:12,自引:4,他引:8
本文基于人均钢消费量与人均GDP“S”形规律, 对典型发达国家工业化过程钢消费量峰值年份进行截面分析, 并依据我国经济增长发展目标厘定高、参考及低三种方案, 解析中国未来钢需求, 结论是: 按高增长方案, 我国人均钢消费峰值点将在2015年到达, 届时人均钢消费量480~500千克, 消费总量6.7~7亿吨; 按参考方案, 我国人均钢消费峰值点将在2015-2016年到达, 届时人均钢消费量430~470千克, 消费总量为6~6.5亿吨; 按低增长方案, 我国人均钢消费峰值点将在2017-2018年到达, 届时人均钢消费量400~440千克, 消费总量为5.6~6.1亿吨。 相似文献
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《Marine Policy》2014
The research uses household survey data collected from 656 people in Townsville (adjacent to the Great Barrier Reef, Australia) within a hurdle model to investigate key factors influencing both the probability of participating and the frequency of (a) boating trips which involve fishing; (b) boating trips which do not involve fishing; and (c) land-based fishing trips. The findings suggest that there are differences in determinants, highlighting the importance of disaggregating the fishing/boating and boat/land-based experience (an uncommon practice in the literature) if wishing to obtain information for use in the design of monitoring programs, policy and/or for developing monitoring and enforcement strategies relating to fishing and boating. 相似文献
59.
随着环境变化加剧、技术进步扩散、城市化生活转向等因素的交织叠加,日常活动空间的供需过程需要并可以更具韧性,但既有研究鲜有涉及。因而,聚焦中国社会经济发展主要矛盾,挖掘面向城市居民日常活动与环境供需矛盾的城市韧性内涵,建构有机整合的理论框架和评估指标体系,并以南京市中心城区为例,依托地理大数据支撑,进行日常活动-环境系统的韧性评估及空间特征研究。主要结论:① 韧性要素在活动与环境间以及数量与质量之间的供需结构失调,且供需不均衡和不充足的问题同时存在并相互制约。② 活动韧性、环境韧性各自的空间分异显著且供需水平及相互匹配程度较低,导致系统韧性呈现低水平蔓延的空间形态。③ 活动韧性、环境韧性及系统韧性之间的空间支撑或匹配作用没有充分发挥,导致日常活动空间的供需关系分异较大且缺少连续良性的空间互动。基于此,应根据韧性演进阶段,促进日常活动空间供需网络的整体动态协同优化。 相似文献
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选择长三角为研究区,构建生态空间质量评价体系,结合可达性分析、统计分析方法,通过人口、GDP、土地开发强度反映生态需求程度,分析生态空间质量的空间分布和生态空间满足人类需求程度的空间分异及演变特征。结果表明:(1)通过融合可达性分析、统计分析方法建立的生态空间供需平衡指数,能很好地识别生态空间供需“短板”。(2)长三角生态空间质量从北向南逐渐升高,1995—2015年生态空间质量较差的区域从各大城市中心部分扩大到城市周边地区。(3)长三角生态空间供需平衡的空间分布具有明显的时空差异,供给不足的区域主要是在经济和城市化发展较快的城市,供大于需的区域主要是在生态高质量区域。 相似文献