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131.
Maciej Tabaszewski Pawe Twardowski Martyna Wiciak-Pikua Natalia Znojkiewicz Agata Felusiak-Czyryca Jakub Czyycki 《Materials》2022,15(12)
The dynamic development of new technologies enables the optimal computer technique choice to improve the required quality in today’s manufacturing industries. One of the methods of improving the determining process is machine learning. This paper compares different intelligent system methods to identify the tool wear during the turning of gray cast-iron EN-GJL-250 using carbide cutting inserts. During these studies, the experimental investigation was conducted with three various cutting speeds vc (216, 314, and 433 m/min) and the exact value of depth of cut ap and federate f. Furthermore, based on the vibration acceleration signals, appropriate measures were developed that were correlated with the tool condition. In this work, machine learning methods were used to predict tool condition; therefore, two tool classes were proposed, namely usable and unsuitable, and tool corner wear VBc = 0.3 mm was assumed as a wear criterium. The diagnostic measures based on acceleration vibration signals were selected as input to the models. Additionally, the assessment of significant features in the division into usable and unsuitable class was caried out. Finally, this study evaluated chosen methods (classification and regression tree, induced fuzzy rules, and artificial neural network) and selected the most effective model. 相似文献
132.
Ovidiu Farc Ioana Berindan-Neagoe Florin Zaharie Liviuta Budisan Oana Zanoaga Victor Cristea 《Oncology Letters》2022,24(3)
Colorectal cancer (CRC) remains a major cause of cancer-related mortality. Consequently, new diagnostic and therapeutic approaches are being investigated including the serum levels of cytokines and other molecules, although the results are often inconclusive. Thus, the present study aimed to determine whether serum level of cytokines, cell adhesion molecules or matrix metalloproteinases (MMPs), alone or in combination, may contribute to the non-invasive diagnosis of CRC. The serum levels of nine cytokines [ILs; IL-1β, IL-4, IL-6, IL-8, IL-10, IL-17, IL-22 and IL-33, and interferon (IFN)-γ], two cell adhesion molecules (intercellular adhesion molecule-1 and P-selectin) and an MMP-7 were measured by ELISA in 33 patients with CRC and 35 healthy controls. Combined capacity of all molecules to detect the presence of CRC was assessed by logistic regression. Molecules and molecule combinations were tested for all stages and tumor grades. A significant increase was identified for IL-8 in patients compared with healthy controls; IL-10 was found to be significantly decreased. The biomarker potential of each significantly modified molecule was tested: IL-8 had a sensitivity of 0.865, a specificity of 0.600 and an area under the curve (AUC) of 0.777; for IL-10, sensitivity was 0.65, specificity was 0.69, with an AUC of 0.689. Logistic regression determined the best discriminative potential between patients and control groups for the combination IL-4 + IL-6 + IL-8 + IFN-γ, with 0.97 sensitivity and 0.58 specificity. For the early stages of CRC, the combination IL-6 + IL-8 + IL-22 showed good performance. It was concluded that increased IL-8 had potential as single biomarker in CRC. Cytokine combinations are superior to single cytokine analysis in showing the presence of CRC. 相似文献
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柯淑丽 《临床超声医学杂志》2023,25(8):654-658
目的 探讨剪切波弹性成像(SWE)参数联合血清中期因子(MK)、胸苷激酶1(TK1)、促甲状腺素与甲状腺球蛋白比值(TSH/Tg)鉴别诊断甲状腺结节良恶性的临床价值。方法 选取我院经术后病理结果或穿刺结果证实的甲状腺结节患者129例,均为单发病灶,其中良性组98例,恶性组31例,均行SWE检查及血清MK、TK1、TSH、Tg检测,比较两组SWE参数[杨氏模量最小值(Emin)、最大值(Emax)、平均值(Emean)],以及血清MK、TK1、TSH/Tg的差异。应用Logistic回归分析建立SWE参数联合血清MK、TK1、TSH/Tg的诊断模型;绘制受试者工作特征(ROC)曲线分析该模型鉴别甲状腺结节良恶性的诊断效能。结果 与良性组比较,恶性组Emax、Emin、Emean及血清MK、TK1、TSH/Tg均升高,差异均有统计学意义(均P<0.05)。应用Logistic回归分析建立SWE参数联合血清MK、TK1、TSH/Tg的诊断模型为:Logit(P)=-0.069+0.101×Emean+0.353×血清MK+0.328×血清TK1+0.882×血清TSH/Tg;ROC曲线... 相似文献
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秦存梅 《中华养生保健(上半月)》2021,(3):14-17
目的 探讨Xpert&MTB/RIF检测法在支气管肺泡灌洗液结核分枝杆菌检测中的应用价值.方法 选取2018年5月~2019年5月山东省枣庄市肿瘤医院收治的150例疑似肺结核患者为研究对象,以支气管肺泡灌洗液作为病原学检测标本,分别以病原学诊断活动性结核病和临床诊断活动性结核病为金标准,以Xpert&MTB/RIF为待... 相似文献
139.
患者女,68岁,体检胸部CT发现双肺多发大小不等结节、左肺上叶团块影(图1A)4个月,纵隔及肺门无肿大淋巴结,无胸腔积液,为进一步诊治入院.MRI:鼻咽部肿块侵入左咽旁间隙(图1B),增强后明显不均匀强化,颈部未见肿大淋巴结.PET/CT:鼻咽部及左肺上叶肿块代谢增高,双肺多发结节;影像学疑诊肺癌并双肺多发转移瘤、鼻咽... 相似文献
140.
患儿男,16岁,无明显诱因左耳听力下降2年、间歇性头痛1年余,未经处理.查体:右眼鼻侧偏盲;外耳道无异常,听力未测.实验室检查:血清生长激素9.49 ng/ml.头颅平扫CT:斜坡及鞍区见团块状稍高欠均匀密度肿块,内见线状及小片状骨化影;斜坡、前床突及后床突骨质不完整(图1A).头颅MRI:斜坡内见团块状等T1、等及稍... 相似文献