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31.
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   
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Iron is an essential nutrient for a child’s proper development at every growth stage. It is crucial for the production of red blood and muscle cells, DNA replication, and the development of the brain, nervous and immune systems. Iron deficiency is the most common micronutrient deficiency in children worldwide. Despite widespread access to nutritional information for children, parents continue to make many feeding mistakes. This study aimed to assess whether any nutritional intervention would affect the iron status in children. The parents of 203 children were randomly assigned to one of two groups: the study group received intensive mobile nutritional education for a year, while the control group received no intervention. Blood tests were performed on both groups at the beginning of the study and one year later. The educational intervention resulted in statistically significantly higher levels of RBC (red blood cells; p = 0.020), HGB (haemoglobin; p = 0.039), HCT (haematocrit; p = 0.036), MCV (mean cell volume; p = 0.018) parameters and iron dietary intake (p ≤ 0.001). Even a non-targeted dietary intervention improves the iron status in children. As iron management is insufficient in most children, an iron-targeted nutritional intervention appears necessary.  相似文献   
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The ferromagnetic resonance (FMR) in the frequency range of 0.5 to 12.5 GHz has been investigated as a function of external magnetic field for rapidly quenched Fe3Co67Cr3Si15B12 amorphous ribbons with different features of the effective magnetic anisotropy. Three states of the ribbons were considered: as-quenched without any treatment; after relaxation annealing without stress at the temperature of 350 °C during 1 h; and after annealing under specific stress of 230 MPa at the temperature of 350 °C during 1 h. For FMR measurements, we adapted a technique previously proposed and tested for the case of microwires. Here, amorphous ribbons were studied using the sample holder based on a commercial SMA connector. On the basis of the measurements of the reflection coefficient S11, the total impedance including its real and imaginary components was determined to be in the frequency range of 0.5 to 12.5 GHz. In order to confirm the validity of the proposed technique, FMR was also measured by the certified cavity perturbation technique using a commercial Bruker spectrometer operating at X-band frequency of 9.39 GHz. As part of the characterization of the ribbons used for microwave measurements, comparative analysis was performed of X-ray diffraction, optical microscopy, transmission electron microscopy, inductive magnetic hysteresis loops, vibrating sample magnetometry, magneto-optical Kerr effect (including magnetic domains) and magnetoimpedance data for of all samples.  相似文献   
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雌激素减少与代谢综合征关系的实验研究   总被引:2,自引:0,他引:2  
目的:探讨雌激素减少与代谢综合征的相关性。方法:在基因库中搜索已知的对脂肪组织有影响的10个基因,筛选其启动子中可能存在的雌激素调控因子的基因。以不同月龄、不同基因型的卵泡刺激素受体敲除 (FORKO)雌鼠为动物模型,测量其腹内白色脂肪组织(WAT)重量、体重,计算腹内WAT与体重的比率;口服葡萄糖(2?g/kg),测快速血糖(0, 30, 60, 120?min)行葡萄糖耐量实验;用组织学方法观察脂肪细胞、肝脏细胞的形态;用放射免疫法测定血清瘦素。结果: ①在7个肥胖相关基因中找到了可能的雌激素调控位点;②FORKO雌鼠于3月龄时出现肥胖,腹内WAT的重量明显高于野生型(P<0.05);③FORKO雌鼠随月龄的增长葡萄糖耐量逐渐减低(P<0.05);④FORKO雌鼠腹内WAT细胞在3月龄时体积较小,表现为增生(P<0.05),而在8个月时表现为肥大(P<0.05);⑤FORKO雌鼠于8月龄时WAT细胞、棕色脂肪(BAT)细胞及肝细胞内均有大量脂酯颗粒堆积;⑥月龄3~5个月的FORKO雌鼠空腹的血清瘦素水平均明显高于野生雌鼠(P<0.05)。结论:FORKO雌鼠因雌激素减少而表现出腹型肥胖、高血糖、高瘦素和胰岛素抵抗等代谢紊乱,提示雌激素减少可导致代谢综合征。  相似文献   
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This report describes a rare case of coexistence of benign phyllodes tumor, which measured 9 cm in the right breast, and invasive ductal carcinoma of 6 cm in the left breast, synchronous and independent, in a 66-year-old patient. The patient underwent a bilateral mastectomy due to the size of both lesions. Such situations are rare and usually refer to the occurrence of ductal or lobular carcinoma in situ when associated with malignant phyllodes tumors, and more often in ipsilateral breast or intra-lesional.  相似文献   
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