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排序方式: 共有790条查询结果,搜索用时 15 毫秒
61.
20 0 1 0 1 2 6印度西北部的普杰地区发生了 7 8级强烈地震。对这次强震事件 ,利用卫星遥感监测地气系统射出长波辐射的数值产品资料 ,分析了以普杰为中心整个西亚范围内 ,事件发生前后共计 6个月的月平均辐射场的分布特征及其演变过程。发现自震前 2个月至震时当月 ,普杰地区始终是一个辐射 (热 )场的高值中心 ,震后明显消散。据此认为印度大地震有可识别的预警信息 ,提出利用卫星遥感技术及其产品 ,有可能为“突破”短临地震预报开拓出一种新的预测技术生长点 相似文献
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64.
L. Stripparo M. Buscaglia M.D. L. Longatti L. Ghisonl F. Dambrosio S. Guerneri F. Rosella M. Lituania M. Cordone P. De Biasio U. Passamonti G. Gimelli C. Cuoco 《黑龙江环境通报》1990,10(6):359-364
Between May 1987 and November 1988, 505 early amniocentesis within the 15th week of gestation were performed at the First Department of Obstetrics and Gynaecology,‘L. Mangiagalli’ of the University of Milan and at the Department of Obstetrics and Gynaecology of ‘Gaslini’ hospital in Genoa. A total number often abnormal fetal karyotypes were diagnosed. In addition, one case of pseudomosaicism (not confirmed on fetal blood) and one case of osteogenesis imperfecta type II (observed at ultrasound examination) were also detected. Eleven pregnancies were therefore terminated because of an abnormal fetus. Out of 494 pregnancies (excluding terminated pregnancies) there were 16 fetal losses within the 28th week; ten of these occurred in the 2 weeks following the procedure. There were 475 live-births, of which 447 were term deliveries and the other 28 deliveries occurred before the 37th week of gestation. 相似文献
65.
设计并介绍分户报警与短信群发结合的报警方式,包括系统采用的布局方法、方案总体设计、整体结构、信息传输网络设计;提出分户报警的新报警策略,并给出分户报警的区域划分方法以及划分的理由和依据。在硬件方面,重点介绍分户警铃的方案,其中包括的两个重要组成部分:无线应急广播发射中心和无线应急广播接收设备;提出采用可寻址智能无线广播的新的技术方法,同时给出建议的设备,总结并分析分户报警系统的功能和特点。通过该警报系统的采用,能大大提高警报通知效率,节省疏散所需的时间。 相似文献
66.
通过对2006年7月- 2007年6月云南地闪定位网探测资料和玉溪大气电场仪资料分析,研究了高原晴天大气电场和雷暴天气过程的电场演变特征.结果表明:高原晴天大气电场具有明显的日变化和月变化特征.低纬高原地区雷暴云具有偶极性和三极性两种结构,但大多数雷暴具有偶极性电荷结构,不同电荷结构的雷暴云的放电特征不同,偶极性时主要为负地闪,地闪活动较活跃;三极性时主要是正地闪,地闪活动较少.根据雷暴云近地面电场变化特征,探讨了大气电场仪预警地闪的方法,首次提出极性变化预警法,其命中率和提前预警时间都明显优于阈值预警法. 相似文献
67.
The whole relationship between environmental variables and firm performance: Competitive advantage and firm resources as mediator variables 总被引:1,自引:0,他引:1
María D. Lpez-Gamero Jos F. Molina-Azorín Enrique Claver-Corts 《Journal of environmental management》2009,90(10):3110-3121
The examination of the possible direct link between environmental protection and firm performance in the literature has generally produced mixed results. The present paper contributes to the literature by using the resource-based view as a mediating process in this relationship. The study specifically tests whether or not the resource-based view of the firm mediates the positive relationships of proactive environmental management and improved environmental performance with competitive advantage, which also has consequences for financial performance. We also check the possible link between the adoption of a pioneering approach and good environmental management practices. Our findings support that early investment timing and intensity in environmental issues impact on the adoption of a proactive environmental management, which in turn helps to improve environmental performance. The findings also show that a firm's resources and competitive advantage act as mediator variables for a positive relationship between environmental protection and financial performance. This contribution is original because the present paper develops a comprehensive whole picture of this path process, which has previously only been partially discussed in the literature. In addition, this study clarifies a relevant point in the literature, namely that the effect of environmental protection on firm performance is not direct and can vary depending on the sector considered. Whereas competitive advantage in relation to costs influences financial performance in the IPPC law sector, the relevant influence in the hotel sector comes from competitive advantage through differentiation. 相似文献
68.
线性修正趋势分析法根据历年数据建立线性模型并进行修正,预测年度、季环境要素污染物变化情况,可应用于空气质量、水环境质量、噪声环境质量、污染源污染物排放等预警预测数据统计分析评价,为环境决策提供技术支持。本文通过实例论述了该方法在实际工作中的应用。 相似文献
69.
基于临水区域化工园区的整体安全研究 总被引:1,自引:1,他引:0
针对临水区域化工园区的生产特点及在整体安全方面存在的普遍问题,提出在临水区域化工园区内要进行合理布局,做到功能分区明确;同时需建立园区安全生产管理、监测预警及应急处置系统,主要是由固定危险源和移动危险源动态安全管理子系统、安全生产监测预警系统、突发事故应急处置平台等所组成;坚持安全监控信息化与标准化,对化工园区的整体安全性的提高将发挥巨大的作用,为建设"平安园区"打下坚实的基础。 相似文献
70.
Increased salinity in spawning and nursery grounds in the Savannah River estuary was cited as the primary cause of a 97% decrease
in adult striped bass (Morone saxatilis) and a concomitant 96% decrease in striped bass egg production. Restoration efforts focused on environmental remediation
and stock enhancement have resulted in restored salinity patterns and increased egg and adult abundances. However, future
water needs or harbor development may preclude further recovery by reducing freshwater inflow or increasing salinity intrusion.
To assess the effect of potential changes in the salinity regime, we developed models relating discharge, tidal phase, and
salinity to striped bass egg and early larval survival and re-cast these in a quantitative Bayesian belief network. The model
indicated that a small upstream shift (≤1.67 km) in the salinity regime would have the least impact on striped bass early
life history survival, whereas shifts >1.67 km would have progressively larger impacts, with a 8.33-km shift potentially reducing
our estimated survival probability by >28%. Such an impact could have cumulative and long-term detrimental effects on the
recovery of the Savannah River striped bass population. The available salinity data were collected during average and low
flows, so our model represents some typical and some extreme conditions during a striped bass spawning season. Our model is
a relatively simplistic, “first-order” attempt at evaluating potential effects of changes in the Savannah River estuarine
salinity regime and points to areas of concern and potential future research. 相似文献