The stiffness model of the finite element is applied to the Kirchhoff-love closed-form plate buckling;buckling is always in focus in plate assemblages. The useful Eigen-value solutions are unable to separate a square ...The stiffness model of the finite element is applied to the Kirchhoff-love closed-form plate buckling;buckling is always in focus in plate assemblages. The useful Eigen-value solutions are unable to separate a square plate from a much weaker long one in the most commonly-used all-simply supported plate (SSSS), among others. Spring-values of the Kirchhoff-Love plate are sought;once found, displacement-factors can be determined. Comparative </span><span style="font-family:Verdana;">displacements allow </span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">an </span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">easier and better evaluation of buckling-factors,</span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"> pure-shear, vibration and so are termed “buckling-displacement-factors”. In testing, many plates in mixed boundary conditions are evaluated for displacement</span></span></span><span><span><span style="font-family:""> </span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">assisted buckling-solutions, first. The displacement-factors made from fundamental Eigen-vectors, in a single-pass, are found to be within about one-percent of known elastic values. It is found that the Kirchhoff-Love plate</span></span></span><span><span><span style="font-family:""> </span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">spring and the finite-element spring, demonstrated, here, in the assemblage of beam-elements, are equivalent from the results. In either case</span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">,</span></span></span><span><span><span style="font-family:""><span style="font-family:Verdana;"> stiffness is first assembled, ready for any loading—transverse, buckling, shear, vibration. The simply-supported plate draws the only exact vibration solution, and so, in an additional new effort, all other results are calibrated from it;direct vibration solutions are made for comparison but such results are, hardly, better. In the process, interactive Kirchhoff-Love plate-field-sheets are presented, for design. It is now additionally demanded that the solution Eigen-vector be </span><span style="font-family:Verdana;">developable into a recognizable deflection-factor. A weaker plate cannot possess greater buckling strength, this is a check;to find stiffness the</span><span style="font-family:Verdana;"> deflection-factor must be exact or nearly so. Several examples justify the characteristic buckling displacement-factor as a new tool</span></span></span></span><span style="font-family:Verdana;">.展开更多
目的:探索乳腺黏液癌(mucinous breast carcinoma,MBC)在多模态超声(multi-parametric ultrasonography,mpUS)即常规超声、剪切波弹性成像(shear wave elastography,SWE)及超声造影(contrast-enhanced ultrasound,CEUS)中的影像学特征,...目的:探索乳腺黏液癌(mucinous breast carcinoma,MBC)在多模态超声(multi-parametric ultrasonography,mpUS)即常规超声、剪切波弹性成像(shear wave elastography,SWE)及超声造影(contrast-enhanced ultrasound,CEUS)中的影像学特征,并评估其对MBC的诊断效能。方法:回顾并纳入2017年1月—2023年4月上海交通大学医学院附属第一人民医院因乳腺病变入院诊治的患者,以术后病理学检查为金标准。根据随机数字表法,按1∶1.5从同期患者中随机选取乳腺纤维腺瘤(fibroadenoma,FA)患者作为对照组。按照乳腺影像报告和数据系统(breast imaging reporting and data system,BI-RADS)分析影像学特征并进行分类。采用logistic回归筛选有效诊断指标,建立预测模型,绘制受试者工作特征曲线,以曲线下面积(area under curve,AUC)评估诊断效能。结果:最终纳入40例MBC患者共40个病灶,包括16例单纯型MBC(pure MBC,PMBC)、24例混合型MBC(mixed MBC,MMBC);60例FA患者,共60个病灶。在常规超声上,50.0%(8/16)的PMBC为BI-RADS 3及4A类,70.8%(17/24)的MMBC为BI-RADS≥4B类。SWE中PMBC和MMBC较FA更多呈不均质质硬表现(62.0%和83.3%vs 25.0%),3~4分是两者与FA鉴别的独立预测因素。CEUS中病变内存在囊性无增强区、边缘增多滋养血管是PMBC与FA鉴别的独立风险因素。相较于MMPC,mpUS较单独常规超声能更显著地提升PMBC与FA的鉴别诊断效能(AUC:0.949 vs 0.858,P<0.05)。结论:MBC,尤其是PMBC,因其与FA在常规超声声像图上存在重叠征象而常被低估,采用mpUS较单独使用常规超声可显著提高其与FA的鉴别诊断效能。展开更多
文摘The stiffness model of the finite element is applied to the Kirchhoff-love closed-form plate buckling;buckling is always in focus in plate assemblages. The useful Eigen-value solutions are unable to separate a square plate from a much weaker long one in the most commonly-used all-simply supported plate (SSSS), among others. Spring-values of the Kirchhoff-Love plate are sought;once found, displacement-factors can be determined. Comparative </span><span style="font-family:Verdana;">displacements allow </span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">an </span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">easier and better evaluation of buckling-factors,</span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"> pure-shear, vibration and so are termed “buckling-displacement-factors”. In testing, many plates in mixed boundary conditions are evaluated for displacement</span></span></span><span><span><span style="font-family:""> </span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">assisted buckling-solutions, first. The displacement-factors made from fundamental Eigen-vectors, in a single-pass, are found to be within about one-percent of known elastic values. It is found that the Kirchhoff-Love plate</span></span></span><span><span><span style="font-family:""> </span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">spring and the finite-element spring, demonstrated, here, in the assemblage of beam-elements, are equivalent from the results. In either case</span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">,</span></span></span><span><span><span style="font-family:""><span style="font-family:Verdana;"> stiffness is first assembled, ready for any loading—transverse, buckling, shear, vibration. The simply-supported plate draws the only exact vibration solution, and so, in an additional new effort, all other results are calibrated from it;direct vibration solutions are made for comparison but such results are, hardly, better. In the process, interactive Kirchhoff-Love plate-field-sheets are presented, for design. It is now additionally demanded that the solution Eigen-vector be </span><span style="font-family:Verdana;">developable into a recognizable deflection-factor. A weaker plate cannot possess greater buckling strength, this is a check;to find stiffness the</span><span style="font-family:Verdana;"> deflection-factor must be exact or nearly so. Several examples justify the characteristic buckling displacement-factor as a new tool</span></span></span></span><span style="font-family:Verdana;">.
文摘目的:探索乳腺黏液癌(mucinous breast carcinoma,MBC)在多模态超声(multi-parametric ultrasonography,mpUS)即常规超声、剪切波弹性成像(shear wave elastography,SWE)及超声造影(contrast-enhanced ultrasound,CEUS)中的影像学特征,并评估其对MBC的诊断效能。方法:回顾并纳入2017年1月—2023年4月上海交通大学医学院附属第一人民医院因乳腺病变入院诊治的患者,以术后病理学检查为金标准。根据随机数字表法,按1∶1.5从同期患者中随机选取乳腺纤维腺瘤(fibroadenoma,FA)患者作为对照组。按照乳腺影像报告和数据系统(breast imaging reporting and data system,BI-RADS)分析影像学特征并进行分类。采用logistic回归筛选有效诊断指标,建立预测模型,绘制受试者工作特征曲线,以曲线下面积(area under curve,AUC)评估诊断效能。结果:最终纳入40例MBC患者共40个病灶,包括16例单纯型MBC(pure MBC,PMBC)、24例混合型MBC(mixed MBC,MMBC);60例FA患者,共60个病灶。在常规超声上,50.0%(8/16)的PMBC为BI-RADS 3及4A类,70.8%(17/24)的MMBC为BI-RADS≥4B类。SWE中PMBC和MMBC较FA更多呈不均质质硬表现(62.0%和83.3%vs 25.0%),3~4分是两者与FA鉴别的独立预测因素。CEUS中病变内存在囊性无增强区、边缘增多滋养血管是PMBC与FA鉴别的独立风险因素。相较于MMPC,mpUS较单独常规超声能更显著地提升PMBC与FA的鉴别诊断效能(AUC:0.949 vs 0.858,P<0.05)。结论:MBC,尤其是PMBC,因其与FA在常规超声声像图上存在重叠征象而常被低估,采用mpUS较单独使用常规超声可显著提高其与FA的鉴别诊断效能。
