An algorithm for precisely calculating the inductance of a three-section solenoid is presented, which is based on summing the layer self-inductances and the mutual inductances. A theoretical model with ex plicit expre...An algorithm for precisely calculating the inductance of a three-section solenoid is presented, which is based on summing the layer self-inductances and the mutual inductances. A theoretical model with ex plicit expressions is firstly developed to calculate the self-inductance of a single layer, and then numerical calcu lation of the mutual inductance between two layers is introduced. Using the presented computation method, the inductance of a solenoid designed in the experiment is successfully calculated （4.30 mH）, which has a difference of less than 1% from the experimental data.展开更多
目的:探讨子宫肌层3层缝合对剖宫产术后憩室大小的影响及子宫切口憩室(CSD)形成的相关因素。方法:回顾性分析2022年4~11月于华东师范大学附属芜湖医院行剖宫产术的240例产妇的临床资料,根据子宫肌层缝合方式的不同分为3层缝合组(124例)...目的:探讨子宫肌层3层缝合对剖宫产术后憩室大小的影响及子宫切口憩室(CSD)形成的相关因素。方法:回顾性分析2022年4~11月于华东师范大学附属芜湖医院行剖宫产术的240例产妇的临床资料,根据子宫肌层缝合方式的不同分为3层缝合组(124例)和双层缝合组(116例);另根据术后是否形成CSD将产妇分为CSD组(23例)和非CSD组(217例)。对比3层缝合组与双层缝合组产妇的临床特点,采用多因素Logistic回归分析CSD形成的独立影响因素并构建人工神经网络模型;采用受试者工作特征(ROC)曲线、校准曲线和临床决策曲线进行模型验证。结果:①3层缝合组产妇的子宫肌层瘢痕厚度显著高于双层缝合组(7.06±2.09 mm vs.5.68±1.97 mm);而CSD形成情况(4.03%vs.15.52%)和憩室大小(0.36±0.09 ml vs.0.47±0.12 ml)则显著低于双层缝合组,差异均有统计学意义(P<0.05);②多因素分析示,子宫后屈、剖宫产次数≥2次、胎膜早破、围产期感染、剖宫产时机(择期)是影响CSD形成的独立危险因素(OR>1,P<0.05),而子宫肌层3层缝合是保护性因素(OR<1,P<0.05);③人工神经网络预测模型显示剖宫产次数、胎膜早破以及是否进行3层缝合所占权重均较高,经ROC曲线、校准曲线和临床决策曲线验证表明该模型预测能力良好。结论:CSD的形成与子宫后屈、剖宫产次数、胎膜早破、围产期感染、剖宫产时机等指标有关,临床应重点关注,此外,子宫肌层3层缝合可降低CSD的形成概率,在临床上值得推广应用。展开更多
文摘An algorithm for precisely calculating the inductance of a three-section solenoid is presented, which is based on summing the layer self-inductances and the mutual inductances. A theoretical model with ex plicit expressions is firstly developed to calculate the self-inductance of a single layer, and then numerical calcu lation of the mutual inductance between two layers is introduced. Using the presented computation method, the inductance of a solenoid designed in the experiment is successfully calculated （4.30 mH）, which has a difference of less than 1% from the experimental data.
文摘目的:探讨子宫肌层3层缝合对剖宫产术后憩室大小的影响及子宫切口憩室(CSD)形成的相关因素。方法:回顾性分析2022年4~11月于华东师范大学附属芜湖医院行剖宫产术的240例产妇的临床资料,根据子宫肌层缝合方式的不同分为3层缝合组(124例)和双层缝合组(116例);另根据术后是否形成CSD将产妇分为CSD组(23例)和非CSD组(217例)。对比3层缝合组与双层缝合组产妇的临床特点,采用多因素Logistic回归分析CSD形成的独立影响因素并构建人工神经网络模型;采用受试者工作特征(ROC)曲线、校准曲线和临床决策曲线进行模型验证。结果:①3层缝合组产妇的子宫肌层瘢痕厚度显著高于双层缝合组(7.06±2.09 mm vs.5.68±1.97 mm);而CSD形成情况(4.03%vs.15.52%)和憩室大小(0.36±0.09 ml vs.0.47±0.12 ml)则显著低于双层缝合组,差异均有统计学意义(P<0.05);②多因素分析示,子宫后屈、剖宫产次数≥2次、胎膜早破、围产期感染、剖宫产时机(择期)是影响CSD形成的独立危险因素(OR>1,P<0.05),而子宫肌层3层缝合是保护性因素(OR<1,P<0.05);③人工神经网络预测模型显示剖宫产次数、胎膜早破以及是否进行3层缝合所占权重均较高,经ROC曲线、校准曲线和临床决策曲线验证表明该模型预测能力良好。结论:CSD的形成与子宫后屈、剖宫产次数、胎膜早破、围产期感染、剖宫产时机等指标有关,临床应重点关注,此外,子宫肌层3层缝合可降低CSD的形成概率,在临床上值得推广应用。
