Analysis of Hydrological Drought Characteristics in Fuhe River Basin Based on Copula Function by LONG Peng, JIAN Hongfu, HAN Huiming, LIU Mingchao

“…In this paper, taking the Fuhe River basin as the study area, the SWAT model is used to obtain runoff sequences for 31 sub-basins in the study area and compute the Standardized Runoff Index (SRI). The tour theory and the conditional probability methods of the Copula function are applied to compare and analyze the hydrological drought characteristics in the basin. …”
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Copula-Based Joint Flood Frequency Analysis: The Case of Guder River, Upper Blue Nile Basin, Ethiopia by Mesfin Mamo Haile, Rakesh Khosa, Asnake Kassahun Abebe, Ayansa Teshome Gelalcha, Abera Misgana Tolera

“…However, for the design of hydrological and hydraulic systems, it is essential to have a thorough understanding of flood event characteristics, including volumes, peaks, time of occurrence, and duration. This study utilizes copula functions for bivariate modeling of flood peak and volume characteristics, examining the performance of four Archimedean copulas in the Guder basin located in Ethiopia from 1987 to 2017. …”
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Study on the Transfer Threshold from Meteorological to Hydrological Drought in Dongjiang River Basin by MO Xiaomei, TU Xinjun, WANG Tian, XIE Yuting, ZHAO Guoyang

“…The study on transfer threshold between different drought types can effectively analyze the occurrence law and mechanism of drought transfer,especially the study on transfer threshold from meteorological drought to hydrological drought.Taking the Dongjiang River Basin as the research object,this paper calculates the standardized precipitation index (SPI) and the standardized runoff index (SRI) at month scale,identifies and extracts the drought events and their characteristics,including drought duration and drought severity based on the run theory,matches the meteorological drought events and hydrological drought events that occur at the fully or partially same time,fits the edge distribution of the matched drought characteristic attributes to verify the correlation between the duration or severity of meteorological and hydrological droughts,establishes the joint distribution models of meteorological drought and hydrological drought based on two-variable Copula function,calculates the conditional probability of different grades of hydrological drought (moderate drought,severe drought and extreme drought) under different meteorological drought conditions,and takes the drought duration or severity value corresponding to the conditional probability of 0.95 as the drought duration or severity threshold for the transfer of meteorological drought to the hydrological drought of this grade.The results show that:The optimal fit functions of meteorological drought duration and severity in the Dongjiang River Basin were gamma distribution.The optimal fit function of hydrological drought duration is gamma distribution,and the marginal distribution function of hydrological drought severity was generalized normal distribution.The drought duration and severity were better when fitting by the Gumbel-copula function.The thresholds of drought duration of middle,severe and extreme drought grades in Dongjiang River basin were 6.9 months,8.3 months,9.4 months,respectively.While the thresholds of drought severity were 4.6,5.7 and 6.6,respectively.Drought transfer threshold can provide reference for hydrological drought prediction and government decision-making of drought prevention and mitigation.…”
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Time Varying Reliability Analysis of the MG 400/951 Shearer Cutting Part Planet Carrier by Minghao Li, Jie Qiao, Lijuan Zhao, Jiayi Fan, Meichen Zhang, Bing Luo

“…According to the fatigue life reliability theory，the fatigue life reliability model of planetary carrier is established. …”
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