期刊文献+
共找到2篇文章
< 1 >
每页显示 20 50 100
基于物理成因识别的第二松花江汛期径流预报 被引量:3
1
作者 孙虹 李鸿雁 +1 位作者 郭道华 鲍珊珊 《水利水电技术》 北大核心 2019年第3期45-51,共7页
针对第二松花江流域中长期径流预测精度较低问题,为了分析物理预报因子的作用过程以提高汛期洪水预报精度,选取太阳黑子相对数为物理影响因素,进而识别其影响时滞,以影响时滞期内的太阳黑子相对数作为径流预报因子,以汛期(6—9月份)月... 针对第二松花江流域中长期径流预测精度较低问题,为了分析物理预报因子的作用过程以提高汛期洪水预报精度,选取太阳黑子相对数为物理影响因素,进而识别其影响时滞,以影响时滞期内的太阳黑子相对数作为径流预报因子,以汛期(6—9月份)月平均径流为预报项目,采用BP神经网络识别映射关系,采用历史资料作为训练样本,完成网络训练和检验。以第二松花江干流控制性水利工程丰满水库为例,对2017年汛期月平均径流进行预报。结果表明:丰满水库汛期月平均入库流量为1 400 m^3/s,来水频率为11%,定性预报第二松花江流域2017年为丰水年;2017年丰满水库实际来水141.00亿m^3,为多年均值的112%,为偏丰来水年份,来水定性预报正确。该方法的创新点在于:采用全局敏感性分析方法识别太阳活动的影响时滞,以确定预报因子;采用BP网络模拟预报因子与预报项目的复杂非线性相关关系,以构建预报网络。研究成果为2017年吉林省水文预报和防汛决策提供了重要支撑。 展开更多
关键词 太阳黑子 敏感性分析 非线性映射识别 长期径流预报 洪水预报 干旱洪涝灾害 防汛抗旱
下载PDF
PRELIMINARY STUDY ON THE FLOODING AND DROUGHT CALAMITY DURING PAST 1500 YEARSIN THE HAI'AN REGION, JIANGSU PROVINCE 被引量:2
2
作者 ZHANGQiang CHENGJi 《Chinese Geographical Science》 SCIE CSCD 2002年第2期146-151,共6页
Collection and arrangement of the historical records of climatic changes andenvironment evolution, especially in the aspect of calamities, are made on the history documents ofpast 1500 years about Hai'an region, J... Collection and arrangement of the historical records of climatic changes andenvironment evolution, especially in the aspect of calamities, are made on the history documents ofpast 1500 years about Hai'an region, Jiangsu Province. There existed two obvious flooding-droughtfrequently-occurring periods: one was from 1550 AD to 1850 AD and another was 1000 AD to 1200 AD.The period of 1550 AD to 1850 AD is interrupted by two relatively arid and cold climatic periods:one was from 1630 AD to 1700 AD and another was 1750 AD to 1820 AD. The main characteristic of thecalamity periods is that they occurred by turns, and sometimes, both drought and flooding occurredin the same year. The instability of the climatic changes in the Little Ice Age may be the mainreason of the frequently-occurring flooding and drought in Hai'an region. Research results also showthat the frequently-occurring periods of flooding and drought is in close relationship with thesolar activity, and therefore, occurrence of the flooding and drought may be in relation with theintensity of the solar activity. This hypothesis may need further study in the future. 展开更多
关键词 hai'an region flooding calamity drought calamity history document
下载PDF
上一页 1 下一页 到第
使用帮助 返回顶部