摘要
利用Pettitt非参数检验法和Mann-Kendall非参数趋势检验法,分析年最大洪峰流量序列的非一致性,确定序列的变异形式,采用"分解-合成"理论对其进行一致性修正,得到过去、现状两种条件下年最大洪峰流量序列,根据贝叶斯理论对序列一致性修正前后参数不确定性进行估计,并对其预报区间优良性进行评价。研究结果表明:年最大洪峰流量序列变异点发生在1993年,序列整体上升趋势不显著,在1957-1993年子序列呈显著下降趋势,而1994-2006年子序列变化趋势不显著,跳跃变异为序列主要变异形式;给出了实测、还原及还现序列参数后验分布估计值及95%置信区间,将其结合优化适线法进行P-Ⅲ型频率分析,得到修正前后设计频率年最大洪峰流量预报区间估计值;还原、还现序列与实测序列相比,预报区间覆盖率均提高24%,平均带宽分别减少39. 59%、23. 17%,平均偏移幅度分别减少28. 45%、11. 39%。通过对非一致性年最大洪峰流量序列还原/还现计算,可减小参数估计不确定性对其计算产生的影响,从而提高预报区间的可靠性。
Pettitt test and Mann-Kendall test were used to analyze the inconsistency of the annual maximum flood peak discharge sequence of the Ken Swart reservoir,and determine the variant form of the sequence. The consistent correction was conducted based on the theory of decomposition-synthesis,then the annual maximum peak discharge sequences under the conditions of past and present were obtained. Bayesian theory was used to estimate the uncertainty of the parameters of the sequences before and after the consistency correction,and evaluate its prediction intervals. The results showed that the change point of the annual maximum peak discharge sequence occurred in 1993,whereas the overall upward trend of the sequence was not significant. Specifically,the subsequence from 1957 to 1993 was significantly decreased,but that from 1994 to 2006 was not significant. And jumping variation was the main variant form. The posteriori distribution estimate and the 95% confidence interval of the parameters of the measured and modified sequences under both the past and present conditions were given.Then combined with the optimized fitting method of P-Ⅲ distribution frequency analysis,the prediction interval estimate of the design flood peak discharge before and after modification were obtained. Compared with the measured sequence,the prediction interval coverage of the modified sequences both increased by 24%,while the average bandwidth decreased by 39. 59% and 23. 17%,and the average migration amplitude decreased by 28.45% and 11. 39% respectively. Therefore,modifying the annual maximum peak discharge under the past and present conditions can reduce the effect of the parameter uncertainty on calculation,and thus improve the reliability of the prediction interval.
作者
陈伏龙
张婷
冯平
何新林
李绍飞
龙爱华
CHEN Fulong;ZHANG Ting;FENG Ping;HE Xinlin;LI Shaofei;LONG Aihua(College of Water Conservancy &Architectural Engineering,Shihezi University,Shihezi 832000,Xinjiang ,China;State Key Laboratory of Hydraulic Engineering Simulation and Safety,Tianjin University,Tianjin 300072,China;Department of Hydraulic Engineering, Tianfin Agriculture University,Tianjin 300384,China;State Key Laboratory of Simulation and Regulation of Water Cycle in River Basin,China Institute of Water Resources and Hydropower Research,Belting 100038,China)
出处
《冰川冻土》
CSCD
北大核心
2018年第5期1004-1015,共12页
Journal of Glaciology and Geocryology
基金
国家自然科学基金项目(51769029)
国家重点研发计划项目(2017YFC0404301)
水利工程仿真与安全国家重点实验室开放基金项目(HESS-1405)
天津市科委应用基础与前沿技术重点项目(15JCZDJC41400)资助
关键词
融雪洪水
跳跃变异
贝叶斯理论
参数估计
不确定性
snowmelt flood
jump variation
bayesian theory
parameter estimation
uncertainty
