目的分析高场强磁共振成像(high field strength magnetic resonance imaging,MRI)对前列腺良恶性病变的鉴别诊断价值。方法选取2016年1月—2021年12月盐城市第三人民医院影像科收治的疑似前列腺病变患者60例,均以高场强MRI检查,以手术...目的分析高场强磁共振成像(high field strength magnetic resonance imaging,MRI)对前列腺良恶性病变的鉴别诊断价值。方法选取2016年1月—2021年12月盐城市第三人民医院影像科收治的疑似前列腺病变患者60例,均以高场强MRI检查,以手术穿刺活检病理诊断结果为金标准,分析高场强MRI诊断效能及影像学特征。结果手术病理确诊30例为良性前列腺增生(阴性)、30例为前列腺癌(阳性)。高场强MRI诊断准确度为95.00%,敏感度为93.33%,特异度为96.67%,阳性预测值为96.55%,阴性预测值为93.55%。经一致性系数分析,高场强与MRI诊断一致性为0.900,一致性良好。前列腺增生:前列腺体积弥漫性增大,T_(2)WI显示前列腺中央叶明显增大,信号不均匀,呈类圆形高信号/低信号,外周带受压变窄。前列腺癌:癌组织呈弥漫性浸润性生长,T_(2)WI移行带呈低信号,边界模糊,病变位于包膜内或突破包膜、侵犯精囊腺或血管神经束,或合并淋巴结肿大、骨盆骨转移。结论高场强MRI在前列腺良恶性病变鉴别诊断中的准确性和可靠性较高,具有推广应用价值。展开更多
水泥生产过程中,分解炉出口温度是非常重要的工艺参数,为了应对出口温度变量的多样性,文章提出一种核主成分分析(kernel principal component analysis,KPCA)与双向长短期记忆(bidirectional long short-term memory,BiLSTM)神经网络相...水泥生产过程中,分解炉出口温度是非常重要的工艺参数,为了应对出口温度变量的多样性,文章提出一种核主成分分析(kernel principal component analysis,KPCA)与双向长短期记忆(bidirectional long short-term memory,BiLSTM)神经网络相结合的温度预测组合模型用来预测分解炉的出口温度。通过KPCA筛选出影响因素的主成分从而达到数据降维目的,将降维后的主成分作为BiLSTM神经网络的输入,分解炉出口温度作为BiLSTM神经网络的输出。经BiLSTM神经网络训练,得到分解炉出口温度预测模型。通过对比验证表明,使用KPCA-BiLSTM相结合的温度预测模型具有较好的预测精度。展开更多
The effects of Ca-based additives on roasting properties of low-grade molybdenum concentrate were studied. The resultsshow that calcium-based additives can react with molybdenum concentrate to form CaSO4 and CaMoO4. T...The effects of Ca-based additives on roasting properties of low-grade molybdenum concentrate were studied. The resultsshow that calcium-based additives can react with molybdenum concentrate to form CaSO4 and CaMoO4. The initial oxidationtemperature of MoS2 is 450℃, while the formation of CaMoO4 and CaSO4 occurs above 500℃. The whole calcification reactionsare nearly completed between 600 and 650℃. However, raising the temperature further helps for the formation of CaMoO4 but isdisadvantageous to sulfur fixing rate and molybdenum retention rate. Calcification efficiency of Ca-based additives follows theorder: Ca(OH)2〉CaO〉CaCO3. With increasing the dosage of Ca(OH)2, the molybdenum retention rate and sulfur-fixing rate rise, butexcessive dosages would consume more acid during leaching process. The appropriate mass ratio of Ca(OH)2 to molybdenumconcentrate is 1:1. When roasted at 650 ℃ for 90 min, the molybdenum retention rate and the sulfur-fixing rate of low-grademolybdenum concentrate reach 100% and 92.92%, respectively, and the dissolution rate of molybdenum achieves 99.12% withcalcines being leached by sulphuric acid.展开更多
文摘目的分析高场强磁共振成像(high field strength magnetic resonance imaging,MRI)对前列腺良恶性病变的鉴别诊断价值。方法选取2016年1月—2021年12月盐城市第三人民医院影像科收治的疑似前列腺病变患者60例,均以高场强MRI检查,以手术穿刺活检病理诊断结果为金标准,分析高场强MRI诊断效能及影像学特征。结果手术病理确诊30例为良性前列腺增生(阴性)、30例为前列腺癌(阳性)。高场强MRI诊断准确度为95.00%,敏感度为93.33%,特异度为96.67%,阳性预测值为96.55%,阴性预测值为93.55%。经一致性系数分析,高场强与MRI诊断一致性为0.900,一致性良好。前列腺增生:前列腺体积弥漫性增大,T_(2)WI显示前列腺中央叶明显增大,信号不均匀,呈类圆形高信号/低信号,外周带受压变窄。前列腺癌:癌组织呈弥漫性浸润性生长,T_(2)WI移行带呈低信号,边界模糊,病变位于包膜内或突破包膜、侵犯精囊腺或血管神经束,或合并淋巴结肿大、骨盆骨转移。结论高场强MRI在前列腺良恶性病变鉴别诊断中的准确性和可靠性较高,具有推广应用价值。
文摘水泥生产过程中,分解炉出口温度是非常重要的工艺参数,为了应对出口温度变量的多样性,文章提出一种核主成分分析(kernel principal component analysis,KPCA)与双向长短期记忆(bidirectional long short-term memory,BiLSTM)神经网络相结合的温度预测组合模型用来预测分解炉的出口温度。通过KPCA筛选出影响因素的主成分从而达到数据降维目的,将降维后的主成分作为BiLSTM神经网络的输入,分解炉出口温度作为BiLSTM神经网络的输出。经BiLSTM神经网络训练,得到分解炉出口温度预测模型。通过对比验证表明,使用KPCA-BiLSTM相结合的温度预测模型具有较好的预测精度。
基金Project(51304245)supported by the National Natural Science Foundation of ChinaProject(2014T70691)supported by the Postdoctoral Science Foundation of China+1 种基金Project(2015CX005)supported by the Innovation Driven Plan of Central South University,ChinaProject supported by the Hunan Provincial Co-innovation Center for Clean and Efficient Utilization of Strategic Metal Mineral Resources,China
文摘The effects of Ca-based additives on roasting properties of low-grade molybdenum concentrate were studied. The resultsshow that calcium-based additives can react with molybdenum concentrate to form CaSO4 and CaMoO4. The initial oxidationtemperature of MoS2 is 450℃, while the formation of CaMoO4 and CaSO4 occurs above 500℃. The whole calcification reactionsare nearly completed between 600 and 650℃. However, raising the temperature further helps for the formation of CaMoO4 but isdisadvantageous to sulfur fixing rate and molybdenum retention rate. Calcification efficiency of Ca-based additives follows theorder: Ca(OH)2〉CaO〉CaCO3. With increasing the dosage of Ca(OH)2, the molybdenum retention rate and sulfur-fixing rate rise, butexcessive dosages would consume more acid during leaching process. The appropriate mass ratio of Ca(OH)2 to molybdenumconcentrate is 1:1. When roasted at 650 ℃ for 90 min, the molybdenum retention rate and the sulfur-fixing rate of low-grademolybdenum concentrate reach 100% and 92.92%, respectively, and the dissolution rate of molybdenum achieves 99.12% withcalcines being leached by sulphuric acid.