Les manifestations tectoniques synsédimentaires associées à la compression éocène en Tunisie : implications paléogéographiques et structurales sur la marge Nord-Africaine

In central Tunisia, a synsedimentary tectonic episode has been pointed out through the tectonic movements affecting the Late Palaeocene–Early Eocene successions. This tectonic episode has controlled, to a large extent, the palaeogeographic setting of the area during that period and confirmed the important effect induced by the Pyrenean shortening phase on the edge of the African plate, which obviously has witnessed a common history with the southern part of the European plate. To cite this article: A. El Ghali et al., C. R. Geoscience 335 (2003).     

青藏高原1∶25万区域地质调查地貌年代学研究

高原隆升及剥蚀作用的复杂性与区域差异性以及高原恶劣的气候、地理条件,使得在青藏高原空白区1∶25万区域地质调查中进行地貌年代学研究具有很大的现实意义.由于地貌是高原隆升、环境演化、新构造运动等的信息载体,地貌年代有助于重塑这些地质作用的发生时间及发展过程,因此地貌年代学研究具有重要的技术意义.1∶25万银石山幅的工作表明,地貌年代学调查对高原隆升及环境演化过程研究具有良好效果.     

Communities as the agents of commodification: The Kumbo Water Authority in Northwest Cameroon

In 1991 the people of the town of Kumbo in Northwest Cameroon expelled the national water corporation from town by force. They claimed to be retrieving a network that the community rightfully owned and they began to run the system along community lines. The paper tells the story of that water supply twice. First it reproduces the popular accounts that circulated in the 1990s that emphasize the role played by the community in the development and operation of the water supply and portray recent events as a triumph of community management. Then it retells the story using archive evidence that puts a quite different light on some of the events. It is argued that the emphasis on community management has a tendency to obscure other important aspects of the story, for example its political context and consequences. It is suggested that the widespread admiration for any initiative that is community based often results in an uncritical analysis of this form of development project. In this case the commodification of water accelerates after the community has wrested control of this public service from the state.     

粗粒料流变研究的现状与展望

粗粒料是土石坝的主要填料,高土石坝的流变已成为坝工专家和工程师广为关注的问题,其流变特性是研究的基础。分析了粗粒料流变研究的现状,介绍了长江科学院新取得的进展,并对粗粒料流变研究的前景提出了展望。     

真空-堆载联合预压处理软基效果的室内试验研究

对甬-台-温高速公路采用真空-堆载联合预压处理软基前后的土样进行了室内试验分析,得出了合理的试验结论,即土的物理性质指标分别得到不同程度的降低,强度指标得到较大的提高。     

济宁二号矿孤岛工作面冲击矿压危险及其控制

孤岛工作面及其周围巷道附近应力集中程度高,顶板运动剧烈,再加上地质构造的影响,采深较大时,冲击危险程度就高,很容易引发冲击矿压。《煤矿安全规程》要求孤岛工作面按冲击矿压危险工作面来管理。孤岛工作面冲击矿压危险检测预报及控制的技术是先分析冲击危险程度,确定冲击危险指数,提出早期预报;采用电磁辐射和钻屑法进行及时预报;采用卸压爆破进行处理,并采用电磁辐射和钻屑法检验防治措施的效果。实践证明,这套技术安全、可靠、有效,能够保证工作面的安全高效生产。     

冬季北极涛动和华北冬季气温变化关系研究

利用北极涛动指数（AOI）、NCEP／NCAR40a再分析资料中的海平面气压（SLP）、850、500、200hPa等压面高度场资料及中国160站月平均气温资料，运用小波分析，经验正交函数（EOF）分析等方法，分析了华北冬季气温和冬季北极涛动指数的变化特征及其关系。结果表明它们之间存在有着显著相关，特别是在年代际尺度上关系尤其密切。华北在20世纪70年代初以前为持续冷冬，80年代中期之后变为持续暖冬，其间相对正常，而冬季北极涛运指数亦存在类似的3个阶段，冬季北极涛动高（低）低数年，华北地区为暖（冷）冬年。其原因在于，北极涛动在于对流层低层和高层都可激发类似EU遥相关型的异常，通过影响西伯利亚高压和东亚大槽影响华北地区气温。强（弱）涛运年大气环流具有弱（强）东亚冬季风特征，西伯利亚高压减弱（增强），亚洲大陆地面东北风减弱（增强），高空东亚大槽减弱（增强）。     

单一震源下生命线系统失效概率分析的新方法(一)--系统可靠路径与失效路径的识别

本文第一部分提出一类识别生命线系统可靠路径与失效路径的新方法，该方法从系统发生概率最大的可靠路径出发，采用递推分解的思路，识别出系统的互斥可靠路径和互斥失效路径，并给出系统失效概率的表达式和失效概率上下界表达式。实例分析表明，该识别方法的计算复杂性较小并具有较高的运算效率。     

THE ANALYSIS ON THE STATISTICAL CHARACTER OF QUIKSCAT SCATTEROMETER WINDS AND STRONG WIND FREQUENCY USING REMOTE SENSOR DATA FROM QUIKSCAT

1 INTRODUCTION Most of the conventional sea surface wind data are measurements from ships, buoys and islands, with coverage and spatial resolution far below the requirements of research and application. At present, due to limited understanding of physical processes and efficient exploitation of data, numerical prediction models have not been used as they should be, although routine procedures are able to give sea surface wind fields at the intervals of 6 hours. With the development of sp…