The working frequency selection of the ZK30525 vibrating screen was studied using ANSYS. Integrating the dynamic performance simulation analysis of the vibrating screen structure, the variation laws of beams＇ vibrati...The working frequency selection of the ZK30525 vibrating screen was studied using ANSYS. Integrating the dynamic performance simulation analysis of the vibrating screen structure, the variation laws of beams＇ vibration displacements changing with different exciting frequencies were researched. These beams include six beams, with one discharging beam and one in-material beam. Results indicate that vibration displacements in the middle of these beams increase with the augmenta- tion of exciting frequency. When exciting frequency exceeds a certain value, there exists a flat change region for vibration displacement. According to vibrator characteristics, the vibrating screen＇s working frequency should be selected in the flat change region, and be far away from modal frequencies. The study provides theoretical guidance for the reasonable working frequency selection of the large-scale vibrating screen.展开更多
目的通过回顾性研究验证双参数膀胱影像报告体系(Vesical Imaging-Reporting and Data System,VIRADS)评分系统[T2加权(T2 weighted image,T2WI)和扩散加权(diffusion weighted image,DWI)]与多参数VI-RADS评分系统[T2WI、DWI与动态增强...目的通过回顾性研究验证双参数膀胱影像报告体系(Vesical Imaging-Reporting and Data System,VIRADS)评分系统[T2加权(T2 weighted image,T2WI)和扩散加权(diffusion weighted image,DWI)]与多参数VI-RADS评分系统[T2WI、DWI与动态增强(dynamic contrast enhance,DCE)]在膀胱癌患者磁共振诊断价值应用的研究。方法调取2020年1月–2021年12月于我院泌尿外科因膀胱癌就诊且行膀胱磁共振检查的患者影像及临床资料,最终纳入膀胱癌患者215例,其中男性183例,女性32例,平均年龄(67.60±11.42)岁。所有病例均经过病理组织切片确诊膀胱癌。两位医师双盲对多序列单独评分,对比双参数与多参数评价系统对膀胱癌的诊断效能。使用受试者工作特征(receiver operator characteristic,ROC)曲线诊断试验及Cohen's Kappa分析进行诊断效能评价及一致性分析。结果两位医师使用多参数VIRADS评分系统在总体中曲线下面积(area under the curve,AUC)及其95%置信区间为0.878(0.830~0.925)和0.856(0.805~0.907);双参数为0.889(0.844~0.934)和0.856(0.805~0.907),差异无统计学意义。在以TURBT亚组分析中差异也无统计学意义,两位医师的一致性评价Kappa值在多参数与双参数评价中分别为0.694与0.546(以VI-RADS≥3分为阳性)和0.693与0.712(以VI-RADS≥4分为阳性),且P均<0.001。结论VI-RADS双参数评分系统的诊断效能不劣于多参数评分系统,为对比剂过敏等无法进行增强检查的患者提供了选择。展开更多
文摘The working frequency selection of the ZK30525 vibrating screen was studied using ANSYS. Integrating the dynamic performance simulation analysis of the vibrating screen structure, the variation laws of beams＇ vibration displacements changing with different exciting frequencies were researched. These beams include six beams, with one discharging beam and one in-material beam. Results indicate that vibration displacements in the middle of these beams increase with the augmenta- tion of exciting frequency. When exciting frequency exceeds a certain value, there exists a flat change region for vibration displacement. According to vibrator characteristics, the vibrating screen＇s working frequency should be selected in the flat change region, and be far away from modal frequencies. The study provides theoretical guidance for the reasonable working frequency selection of the large-scale vibrating screen.
文摘目的通过回顾性研究验证双参数膀胱影像报告体系(Vesical Imaging-Reporting and Data System,VIRADS)评分系统[T2加权(T2 weighted image,T2WI)和扩散加权(diffusion weighted image,DWI)]与多参数VI-RADS评分系统[T2WI、DWI与动态增强(dynamic contrast enhance,DCE)]在膀胱癌患者磁共振诊断价值应用的研究。方法调取2020年1月–2021年12月于我院泌尿外科因膀胱癌就诊且行膀胱磁共振检查的患者影像及临床资料,最终纳入膀胱癌患者215例,其中男性183例,女性32例,平均年龄(67.60±11.42)岁。所有病例均经过病理组织切片确诊膀胱癌。两位医师双盲对多序列单独评分,对比双参数与多参数评价系统对膀胱癌的诊断效能。使用受试者工作特征(receiver operator characteristic,ROC)曲线诊断试验及Cohen's Kappa分析进行诊断效能评价及一致性分析。结果两位医师使用多参数VIRADS评分系统在总体中曲线下面积(area under the curve,AUC)及其95%置信区间为0.878(0.830~0.925)和0.856(0.805~0.907);双参数为0.889(0.844~0.934)和0.856(0.805~0.907),差异无统计学意义。在以TURBT亚组分析中差异也无统计学意义,两位医师的一致性评价Kappa值在多参数与双参数评价中分别为0.694与0.546(以VI-RADS≥3分为阳性)和0.693与0.712(以VI-RADS≥4分为阳性),且P均<0.001。结论VI-RADS双参数评分系统的诊断效能不劣于多参数评分系统,为对比剂过敏等无法进行增强检查的患者提供了选择。
