基于AdaBoost算法的多层砖房震害影响因素评估     

马宁  林均岐  刘金龙  贾晗曦 《震灾防御技术》2020,15(2):235-242

多层砖房是最常用的结构形式之一,对其进行震害预测尤为重要,选择合适的影响因素是震害预测中最重要的环节之一。本文基于AdaBoost算法对多层砖房震害影响因素进行评估,给出影响因素重要度排序,并将结果与灰色关联分析法进行比较。研究发现结构合理性、地震峰值加速度、砖墙面积率和场地条件对多层砖房震害影响最大,因此在多层砖房震害预测中应优先考虑这4个因素,并在结构设计建造过程中予以足够重视。  相似文献   

Mainshock-aftershock state-dependent fragility curves: A case of wood-frame houses in British Columbia,Canada     

Lizhong Zhang  Katsuichiro Goda  Flavia De Luca  Raffaele De Risi 《地震工程与结构动力学》2020,49(9):884-903

During a mainshock-aftershock (MSAS) sequence, there is no time to retrofit structures that are damaged by a mainshock; therefore, aftershocks could cause additional damage. This study proposes a new approach to develop state-dependent fragility curves using real MSAS records. Specifically, structural responses before and after each event of MSAS sequences are used to obtain statistical relationships among the engineering demand parameter prior to the seismic event (pre-EDP), the intensity measure of the seismic event (IM), and the engineering demand parameter after the seismic event (post-EDP). The developed fragility curves account for damage accumulation, providing the exceeding probability of damage state (DS) given the IM of the event and the DS of the structure prior to the seismic excitation. The UBC-SAWS model, which was developed for wood-frame houses in British Columbia, Canada, is considered as a case study application. Results indicate that for the examined structural typology, state-dependent fragility curves based on residual interstorey drift ratio (pre-EDP), peak ground velocity (IM), and maximum inter-storey drift ratio (post-EDP) are the best choice to characterise the cumulative damage effect. An illustration of the developed fragility curves is provided by considering a hypothetical MSAS scenario of a M_w 9.0 Cascadia mainshock triggering a M_w 6.0 crustal event in the Leech River fault, affecting wooden houses in Victoria, Canada. The MSAS scenario increases Yellow tags (restricted access) by 12.3% and Red tags (no access) by 4.8%.  相似文献   

膜生物流化床的气液传质特性研究     

赵洪兵  羊依金  谭显东 《成都信息工程学院学报》2009,24(3)

研究了膜生物流化床的传质特性,结果表明,反应器氧传质系数随着固含率的增加先增加后减小,随着气速和液速的增大而增大;气相含率受气速影响显著并随气速及固含率的增大而升高.载体挂膜后,系统的氧传质系数和气含率降低.  相似文献   

Evaluation of temperature trends over India / Evaluation de tendances de température en Inde     

《水文科学杂志》2013,58(1)

Abstract

Abstract The impact of climate change is projected to have different effects within and between countries. Information about such change is required at global, regional and basin scales for a variety of purposes. An investigation was carried out to identify trends in temperature time series of 125 stations distributed over the whole of India. The non-parametric Mann-Kendall test was applied to detect monotonic trends in annual average and seasonal temperatures. Three variables related to temperature, viz. mean, mean maximum and mean minimum, were considered for analysis on both an annual and a seasonal basis. Each year was divided into four principal seasons, viz. winter, pre-monsoon, monsoon and post-monsoon. The percentages of significant trends obtained for each parameter in the different seasons are presented. Temperature anomalies are plotted, and it is observed that annual mean temperature, mean maximum temperature and mean minimum temperature have increased at the rate of 0.42, 0.92 and 0.09°C (100 year)^-1, respectively. On a regional basis, stations of southern and western India show a rising trend of 1.06 and 0.36°C (100 year)^-1, respectively, while stations of the north Indian plains show a falling trend of –0.38°C (100 year)^-1. The seasonal mean temperature has increased by 0.94°C (100 year)^-1 for the post-monsoon season and by 1.1°C (100 year)^-1 for the winter season.  相似文献   

注重新形势下自然岸线管控的海岸线分类体系探讨     

修淳  霍素霞  姚海燕  段海钦  杜明 《地理科学》2022,42(2):333-342

海岸线分类体系是海洋自然资源调查与管理、海岸线保护与利用的基础依据。在梳理现有海岸线分类体系的基础上,以易于操作和注重实用为原则,构建了面向于新形势下自然岸线管控的涵盖3个一级类、7个二级类、12个三级类的海岸线分类体系,进一步细化了自然岸线分类。新分类体系的建立是对贯彻《海岸线保护与利用管理办法》的积极实践,有助于对海岸线资源进行精细化管理,也可为实施海岸线整治修复提供重要支撑。  相似文献   

HFS绳索取心孔底局部反循环三合管组合取心钻具          下载免费PDF全文

唐进军  刘海斌 《探矿工程》2014,41(2):52-55,63

介绍了研制成功的HFS绳索取心孔底局部反循环三合管组合取心钻具的结构和工作原理,喷反元件参数设计,及其室内模拟试验和现场试验情况。  相似文献   

Ms 6.5 Earthquake Occurred in Ludian County of Yunnan Province,China, Although Forecast Issued before the Earthquake,Life Casualties and Property Losses were Still Caused Significant     

HAO Ziguo  FEI Hongcai  LIU Lian  and Susan TURNER 《《地质学报》英文版》2014,88(4):1334-1336

正1 Geography Location At 16:30 on August 3rd,2014,Ludian County,Zhaotong City,Yunnan Province(27.1°N,103.3°E)was hit by Ms 6.5earthquake,with the maximum intensity is 9 and epicenter depth is around 12 km(Figs.1 and 2).  相似文献   

浅析沿空留巷技术     

孙学军 《吉林地质》2014,(2):139-142

鄂尔多斯闫家渠煤矿1404采煤工作面上风巷采用沿空留巷技术,实现了工作面"Y"型通风,既解决了上隅角一氧化碳积聚问题,又解决了采掘接续紧张问题,同时提高了采区回采率。  相似文献   

论房屋租赁权的用益物权性质     

孙展望  罗秀兰 《广东海洋大学学报》2006,26(2):47-51

民事财产性权利主要包括物权和债权,物权的保护力度强于债权已为众所公认。于是在一定的社会形势下,对于某种法益囿于其债权性质而难以得到有力保护时,物权法可在不违背其法律逻辑的前提下对其伸出援手,即法定其为物权。房屋租赁权长期以来被定性为债权(或特殊债权),但在我国房价居高不下,越来越多人选择租房方式来改善或解决房屋利用问题,应将房屋租赁权提升为一种用益物权,这是目前相关立法的逻辑清晰化需要。  相似文献   

面向海岛民居抗震性能评估的信息提取方法研究          下载免费PDF全文

贾婧  王凌霄  窦圣宇  王春晓  王维欣 《世界地震工程》2021,(4):148-156

我国海岛地震灾害特征明显,民居抗震性能评估是海岛防灾规划的重要内容。基于我国海岛民居特征分析,结合抗震性能评估的工作特点,本文总结了海岛民居抗震性能评估的数据需求,并针对需求提出了综合资料分析、现场调研和无人机航摄的数据获取方式,以及利用GIS、BIM和深度学习技术分析数据、提取信息的处理流程与体系,最终形成了面向海岛民居抗震性能评估的信息提取方法。该方法有助于海岛民居抗震性能评估工作,为海岛抗震防灾规划提供参考。  相似文献