The magnetotelluric sounding method was used to study the active fault in Shenzhen city.Four magnetotelluric profiles with a dense station interval were laid out across the Shenzhen fault zone.The remote reference tec...The magnetotelluric sounding method was used to study the active fault in Shenzhen city.Four magnetotelluric profiles with a dense station interval were laid out across the Shenzhen fault zone.The remote reference technique was used in both data observation and processing to eliminate the electromagnetic noise near the survey sites,and relatively smooth apparent resistivity curves were obtained.TM mode data and two-dimensional inversion method as NLCG were used to obtain the electrical structures underground.According to the surficial geology survey results on regional strata and distribution of magmatic bodies and faults,the electrical structures at depths less than 2000m of each profile were interpreted.Two regional faults,the Henggang-Luohu fault and the Liantang fault,and seven local faults consistent with the electrical boundaries were verified or discovered.The strata in the survey area were then related with the change of resistivity.Electrical horizontal slices of depths less than 5000m indicate that the Henggang-Luohu fault and the Liantang fault bifurcate at the shallow part but tend to merge in the deep part.展开更多
基金sponsored by the "Program for Active Fault Detection and Earthquake Risk Assessment in Shenzhen City",China
文摘The magnetotelluric sounding method was used to study the active fault in Shenzhen city.Four magnetotelluric profiles with a dense station interval were laid out across the Shenzhen fault zone.The remote reference technique was used in both data observation and processing to eliminate the electromagnetic noise near the survey sites,and relatively smooth apparent resistivity curves were obtained.TM mode data and two-dimensional inversion method as NLCG were used to obtain the electrical structures underground.According to the surficial geology survey results on regional strata and distribution of magmatic bodies and faults,the electrical structures at depths less than 2000m of each profile were interpreted.Two regional faults,the Henggang-Luohu fault and the Liantang fault,and seven local faults consistent with the electrical boundaries were verified or discovered.The strata in the survey area were then related with the change of resistivity.Electrical horizontal slices of depths less than 5000m indicate that the Henggang-Luohu fault and the Liantang fault bifurcate at the shallow part but tend to merge in the deep part.
文摘目的利用机器学习算法探究与移植肾功能延迟恢复(delayed graft function,DGF)发生相关的风险因素并建立预测模型。方法收集2018年1月至2020年3月华中科技大学附属同济医院器官移植研究所实施的公民逝世后捐献供肾和肾移植受者的临床资料以及供肾活检病理资料,通过贪心算法筛选与DGF发生相关的因素的贡献度,再利用逻辑回归算法建立预测模型并利用模型精确度,受试者工作特性曲线下面积(area under the receiver operating characteristic curve,AUROC)对模型效果进行评估。结果术后DGF的发生率为21.9%。与术后DGF发生相关性较高的因素包括供者体型、末次尿素氮、冷缺血时间、供器官小动脉病变范围、慢性肾小管萎缩评分(ct)和慢性间质纤维化评分(ci)。使用上述因素建立预测模型,模型的AUROC约为0.71,预测准确率约为0.73。结论利用机器学习算法可以分析DGF发生的风险因素并建立预测模型,以供临床预测DGF的发生风险。
