The quest for refined calibration of the Jurassic time-scale     

József Pálfy 《Proceedings of the Geologists' Association. Geologists' Association》2008,119(1):85-95

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An operational multiscale system for hazards prediction, mapping, and response     

David P. Bacon  Nash’at N. Ahmad  Thomas J. Dunn  Michael C. Monteith  Ananthakrishna Sarma 《Natural Hazards》2008,44(3):317-327

By definition, a crisis is a situation that requires assistance to be managed. Hence, response to a crisis involves the merging of local and non-local emergency response personnel. In this situation, it is critical that each participant: (1) know the roles and responsibilities of each of the other participants; (2) know the capabilities of each of the participants; and (3) have a common basis for action. For many types of natural disasters, this entails having a common operational picture of the unfolding events, including detailed information on the weather, both current and forecasted, that may impact on either the emergency itself or on response activities. The Consequences Assessment Tool Set (CATS) is a comprehensive package of hazard prediction models and casualty and damage assessment tools that provides a linkage between a modeled or observed effect and the attendant consequences for populations, infrastructure, and resources, and, hence, provides the common operational picture for emergency response. The Operational Multiscale Environment model with Grid Adaptivity (OMEGA) is an atmospheric simulation system that links the latest methods in computational fluid dynamics and high-resolution gridding technologies with numerical weather prediction to provide specific weather analysis and forecast capability that can be merged into the geographic information system framework of CATS. This paper documents the problem of emergency response as an end-to-end system and presents the integrated CATS–OMEGA system as a prototype of such a system that has been used successfully in a number of different situations.  相似文献   

Urban consolidation and house prices: a case study of Melbourne 1990–2004     

Sun Sheng Han  Kevin O’Connor 《GeoJournal》2008,73(4):285-295

This paper explores the links between a strategic policy, urban consolidation, and house prices by examining the changes in the mix of housing and in house price for the period 1991–2004. We contend that urban consolidation could be seen as a source of additional supply, (which might be expected to be felt in lower prices and so contribute to a local policy objective) but also as a stimulus to demand (by developers who could bid up the price of lots where it was understood more housing could be built). Analyses were carried out at the metropolitan and sub-regional scales using correlation tests. The research finds very weak statistical connections, and concludes that this policy has not been associated with price changes.  相似文献   

TBM在不良地质洞条件下的施工技术          下载免费PDF全文

刘大军  张益忠 《探矿工程》2008,35(10):60-65

TBM掘进机以其快速、高效、安全、优质等优点越来越广泛地被应用于隧洞开挖施工中,尤其更适用于深埋超长隧洞,然而在不良地质洞段中TBM掘进缓慢,甚至有卡刀可能,反而不如钻爆法灵活,这就需要根据围岩性状采取特殊技术处理措施,辅以监控量测手段对支护方案进行验证、调整支护措施、修正设计参数等。结合辽宁大伙房输水隧洞工程,总结了在不良地质洞条件下的超前地质预报方法、不良地质段处理措施以及围岩变形监测方法。  相似文献   

PSO-RBFNN模型及其在岩土工程非线性时间序列预测中的应用   总被引：1，自引：0，他引：1  

梁桂兰  徐卫亚  何育智  赵延喜 《岩土力学》2008,29(4):995-1000

岩土工程受力变形演化是一个典型的非线性问题,其演化的高度非线性和复杂性,很难用简单的力学、数学模型描述,但可用粒子群优化径向基神经网络对岩土工程应力、位移非线性时间序列进行动态实时预测。网络径向基层的单元数通过均值聚类法确定后,所有其它参数：中心位置、形状参数、网络权值,均通过粒子群优化算法在全局空间优化确定。工程实例应用表明,该模型预测结果准确、精度高,有良好的应用前景。  相似文献   

山东莒南地质公园发现小型兽脚类恐龙足迹化石MinisauripUS     

李日辉  ;Lockley Martin G  ;Matsukawa Masaki  ;刘明渭 《中国区域地质》2008,(1):121-125

在山东省莒南地质公园内发现6个小型恐龙足迹化石,被归入足迹属Minisauripus。化石产于下白垩统大盛群田家楼组．时代为早白垩世巴列姆（Barremian）-阿普特期（Apdan）。5个较大,长约6cm,产于下部“主”层面上,其中4个组成2节行迹：1个较小,长约3cm,位于“主”层面30cm之上的上部层面上。山东Minisauripus的特征是：足迹个体小（长3．1～5．6cm,宽2．0～3．7cm）,三趾型,略不对称;足迹纵长,各趾近平行,趾垫较清晰;趾末端较钝,但爪迹较尖。Ⅲ趾比Ⅳ趾略长,而Ⅳ趾比Ⅱ趾略长且窄。此外,步幅较长,足长与步长之比约为10：1。与四川、韩国Minisau却淞不同之处是：足迹个体较大,长约是它们的2倍。继中国四川和韩国之后,山东是Minisau而淞在全球的第三个发现点。  相似文献   

甘肃庆城庄19井区上三叠统延长组长82亚油层组低渗透储层的地质特征     

谢渊  ;谢正温  ;孙虎  ;鲁洪江  ;刘国良 《中国区域地质》2008,(6):844-854

长82亚油层组是甘肃庆城地区庄19井区上三叠统延长组中储集砂岩相对富集的层位,但砂岩低渗透性的特点显著,成为影响该区石油储产量增长的主要地质因素。结合前人的相关工作,通过钻井岩心观察、测井曲线分析、储层岩石实验测试等工作,详细地分析了庄19井区长82亚油层组低渗透储层的地质特征,认为沉积微相和压实作用、胶结作用是控制低渗透性储集砂岩发育和分布的主要地质因素,寻找以水下分流河道微相为代表的有利储集相带砂岩体是油气勘探的重要方向。  相似文献   

Viewpoint: the interface between scientific advice and fisheries management     

Hoydal  Kjartan 《ICES Journal of Marine Science》2007,64(4):846-850

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GPS卫星反射信号增强技术研究     

杨进佩  刘中  朱晓华 《海洋湖沼通报》2006,(3):13-20

本文根据GPS卫星反射信号在海洋参数测量、无源雷达目标探测以及大地测绘中的应用,从天线接收、信号处理运算和多路径信号抵消角度,详细地研究了GPS卫星反射信号增强技术,给出了相应天线和电路结构及信号处理方法,并进行了计算机仿真,结果表明所提出的技术能增强GPS卫星反射信号。  相似文献   

极化SAR目标相对最优极化研究     

余海坤  张永红  汪云甲 《海洋测绘》2006,26(5):13-15,19

目标相对最优极化就是选取一种极化状态,使得研究目标和背景地物的接收功率对比达到最大。通过讨论了目标相对最优极化问题,提出了改进的模型和解算方法,利用实际数据对其模型和方法进行了实验,验证了其有效性和正确性。  相似文献