排序方式: 共有56条查询结果,搜索用时 156 毫秒
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江苏省气象服务效益研究(Ⅱ)行业气象服务效益评估 总被引:1,自引:1,他引:1
行业气象服务效益虽有很多可以估量的典型事例,但更多的则是潜在于各行各业效益之中的难以测算的社会、经济、环境和生态效益,目前还没有一种完善的评价方法。本文采用德尔斐专家评估法,通过对分布于江苏省各市的一百多位行行业专家咨询调查,由108位专家有效投票的定性评估,得出了一个较为公正、客观、科学、可信的定量结果--江苏省1992年行业气象服务的效益为27.7347亿元,效益投资比为116.1,这项研究成 相似文献
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西安市近10年大气稳定度和边界层厚度特征 总被引:6,自引:0,他引:6
利用西安市1996~2005年逐日24个时次的气象资料,运用修正的Pasquill稳定度分类方法和国标GB/T3840-91规定的边界层厚度计算方法计算出逐日逐时次的稳定度等级和边界层厚度,分析了各类稳定度频率和不同稳定度条件下大气边界层厚度的逐年、逐月变化规律。结果表明:西安市大气稳定度出现的频率以稳定类为主。近10年来不稳定类和稳定类有缓慢上升的趋势,中性类有缓慢下降的趋势。稳定类和不稳定类随季节变化非常明显。西安市春季大气边界层厚度最高,夏季次之,冬季最低。 相似文献
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2000年姚安地震余震序列的剪切波分裂研究 总被引:4,自引:1,他引:3
2000年1月15日姚安MS6.5地震后,云南省地震局在余震区布设的流动数字台网接收到了大量余震序列的数字波形,这为研究姚安地震的性质提供了丰富的资料. 由于剪切波经过上地壳传播时的分裂现象反映了上地壳介质的各向异性,因此在对余震事件进行精确定位的基础上,文中应用互相关系数法计算了余震序列剪切波的分裂参数,并对不同台站和不同区域得到的结果进行了分析讨论. 主要得到以下结论:余震区的平均快波偏振方向受区域应力场控制,与主震最大水平主压应力方向一致;不同台站与不同区域事件的平均快波偏振方向是有差异的,与区域内的构造变化和应力场调整有关;延时大小受多种因素影响,与剪切波传播时经过介质的性质关系密切. 相似文献
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Yongcun Zhao Xianghua Xu Biao Huang Weixia Sun Xuexin Shao Xuezheng Shi Xinling Ruan 《Environmental Geology》2007,52(7):1423-1433
A total of 540 topsoil samples (0–15 cm), 188 subsoil samples (20–40 cm), and four individual soil profiles were collected
in this study for mapping the Cu- and Pb-contaminated areas in soils of Zhangjiagang city, an industrialized city in the Yangtze
River Delta region of China. Robust geostatistical methods were applied for identifying possible spatial outliers of Cu and
Pb data, and then a sequential Gaussian simulation was employed for delineating the potential areas where Cu or Pb concentration
was affected by diffuse pollution. The results showed that the spatial outliers of Cu and Pb were strongly associated with
various types of factories. The anthropogenic input of Cu to soils at local hotspots was closely related to emissions of printing
and dyeing, metallurgical, and chemical factories, whereas a lead oxide factory and a chemical factory resulted in a considerable
increase of Pb in the topsoil of the study area. Approximately 30% of the total land area of the study was at potential risk
from the Cu or Pb diffuse pollution resulting from rapid industrialization of the area over the past 20 years. 相似文献
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本文以绵阳市为例,采用随机抽样的方式对3500余名城市不同层次的人员进行问卷调查,还对目前地方地震机构普遍采用的地震科普知识宣传方法进行了社会检验,综合评判与分析。指出了当前地震宣传工作与社会需求之间的偏差,提出了城市地震科普知识宣传的最佳方法和较好组合模式,以实现目前在人、财、物力十分有限的情况下,发挥最佳经济和社会效益。 相似文献
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A simulation analysis on pelagic-benthic coupling ecosystem of the northern Jiaozhou Bay, Qingdao, China 总被引:3,自引:0,他引:3
Wu Zengmao Zhai Xuemei Zhang Zhinan Yu Guangyao Zhang Xinling Gao Shanhong 《海洋学报(英文版)》2001,20(3):443-453
INTRODUCTIONWith the development of economy and the exploitation of coastal resources, the coastal en-vironment of the northern part of China was seriously damaged, especially in the Jiaozhou Bay.More attention was paid to this phenomenon. Five comprehensive investigations on theecological dynamics of the Jiaozhou Bay were carried out from March to November of 1995. Theaim is to study the annual variation characteristics of the ecosystem dynamics of the Jiaozhou Bay.Yu Guangyao et al.… 相似文献