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便携式LIBS结合SSA-KELM的废钢成分定量分析方法
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作者 黄晓红 刘晓辰 +3 位作者 刘艳丽 宋超 孙永长 张庆军 《光谱学与光谱分析》 SCIE EI CAS CSCD 北大核心 2024年第9期2412-2419,共8页
废钢是电炉炼钢的重要原料,为有效利用废钢,需对废钢中各元素进行检测。提出了麻雀搜索算法优化的核极限学习机(SSA-KELM)与激光诱导击穿光谱技术(LIBS)相结合的新方法,对中低合金钢和低合金钢的钢样共12组样品进行元素含量建模分析。... 废钢是电炉炼钢的重要原料,为有效利用废钢,需对废钢中各元素进行检测。提出了麻雀搜索算法优化的核极限学习机(SSA-KELM)与激光诱导击穿光谱技术(LIBS)相结合的新方法,对中低合金钢和低合金钢的钢样共12组样品进行元素含量建模分析。首先通过便携式LIBS光谱仪采集两类共计12种不同的废钢样品在170~400nm范围内的激光诱导击穿光谱数据,为降低实验波动影响,每个试验样品的表面均匀选取28个不同的位置进行检测,使用K值校验剔除粗大误差,并将剩余数据进行平均处理,最终得到12个样品共336组平均光谱数据;然后对获得的光谱数据进行基线校正和归一化处理,降低基线波动影响;然后选出待检测元素的多条相关谱线共65条作为模型的输入特征,接着对光谱数据进行训练集与测试集的划分,从每类钢种中随机选择一个样品,提取其处理后的光谱数据作为模型的测试集,剩余数据作为模型的训练集,利用麻雀搜索算法(SSA)对核极限学习机(KELM)进行参数寻优,针对相关元素进行建模。最终所建立的C、Cu、Mn、Cr、Ni、Si、V、Al、Ti元素的模型在验证集的相关决定系数(R2)和均方根误差(RMSE)平均为0.996和0.016。实验比较了单变量校正模型和基于遗传算法优化的核极限学习机(GA-KELM)的多变量校正模型的定量分析效果,结果表明,与单变量校正模型和遗传算法和核极限学习机(GA-KELM)模型相比,SSA-KELM模型的所有指标都有显著提高,作为多变量模型的KELM与麻雀搜索算法相结合,能够有效的减弱多种因素对待分析元素的干扰,增强定量分析的性能,通过与便携式LIBS系统结合,可用于现场作业,实现对废钢中各元素含量的快速精准检测。 展开更多
关键词 激光诱导击穿光谱 废钢 麻雀搜索算法 核极限学习机 定量分析
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激光诱导击穿光谱结合XGBSFS特征优选的废钢分类识别方法 被引量:2
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作者 孙永长 刘艳丽 +2 位作者 黄晓红 宋超 程朋飞 《光谱学与光谱分析》 SCIE EI CAS CSCD 北大核心 2023年第2期442-448,共7页
我国每年的钢铁生产与出口量位居世界前列,而在钢铁生产过程中产生的废钢是一种重要的资源。废钢的精准分类是电炉炼钢的关键环节,对于环境能源的可持续发展也具有重要意义。为了提高废钢回收利用的效率,提出了一种利用激光诱导击穿光... 我国每年的钢铁生产与出口量位居世界前列,而在钢铁生产过程中产生的废钢是一种重要的资源。废钢的精准分类是电炉炼钢的关键环节,对于环境能源的可持续发展也具有重要意义。为了提高废钢回收利用的效率,提出了一种利用激光诱导击穿光谱结合XGBSFS特征优选的废钢牌号智能识别方法,与k最邻近算法(kNN)、支持向量机(SVM)分类算法联合建立了XGBSFS-SVM、XGBSFS-kNN两种优化模型。首先通过Lapa-80型固体脉冲激光器采集3类共18种不同的废钢样品在170~400 nm范围内的激光诱导击穿光谱数据,通过k值校验剔除光谱数据中的粗大误差,并对剔除后剩余的数据进行平均,每个样品28组共得到504组平均光谱数据;然后对光谱数据进行基线校正、归一化等预处理,降低基体波动影响;最后将处理后的光谱数据从每类钢种中提取一个样品的数据作为模型的测试集,剩余数据作为模型的训练集,并提取光谱数据中Si,Cu和C等元素的16条特征谱线作为分类特征,用于模型的输入,经过基于XGBoost的XGBSFS特征选择算法对变量进行优化后,应用kNN、SVM建立废钢智能识别模型。XGBSFS-SVM、XGBSFS-kNN算法模型在测试集上的准确率分别为100%和98.8%,输入维数也均由16维降至2维,且两种模型的建模时间分别由3.1下降至2.79 s,3.26 s下降至1.64 s,相较于单独使用SVM和kNN的算法模型,提出的优化模型预测精度和建模效率较高,且泛化能力较好。经过对比建模时间和准确率综合效果,选取XGBSFS-SVM模型用于不同废钢的智能快速识别。实验结果表明,该研究提出的LIBS与XGBSFS特征优选方法能够有效的对特征变量进行优化建模,为工业生产中废钢种类的快速智能识别和钢铁的回收提供了一种新技术。 展开更多
关键词 激光诱导击穿光谱 牌号识别 特征选择 废钢
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阻塞性睡眠呼吸暂停低通气综合征的OPG/RANKL失衡、氧化应激和系统性炎性反应指标的相关性 被引量:2
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作者 马晓蓉 张静宜 +2 位作者 宗运之 孙永昌 王勇 《中华骨质疏松和骨矿盐疾病杂志》 CSCD 北大核心 2021年第5期470-478,共9页
目的观察阻塞性睡眠呼吸暂停低通气综合征(obstructive sleep apnea-hypopnea syndrome,OSAHS)患者骨质疏松相关蛋白骨保护素(osteoprotegerin,OPG)/核因子κ-B受体活化因子配体(receptor activator of nuclear factor-κB ligand,RANKL... 目的观察阻塞性睡眠呼吸暂停低通气综合征(obstructive sleep apnea-hypopnea syndrome,OSAHS)患者骨质疏松相关蛋白骨保护素(osteoprotegerin,OPG)/核因子κ-B受体活化因子配体(receptor activator of nuclear factor-κB ligand,RANKL)系统、抗氧化应激能力、系统性炎性反应、骨转换标志物的变化,探讨氧化应激、系统性炎性反应与OPG/RANKL的相关性。方法通过多导睡眠(polysomnography,PSG)监测入选48例男性OSAHS患者,其中轻中度组19例,重度组29例,<50岁组33例,≥50岁组15例,同时选择经PSG监测排除OSAHS的男性对照组20例。受试者填写Epworth嗜睡量表(Epworth sleepiness scale,ESS)问卷;使用双能X线吸收测量法(dual-energy X-ray absorptiometry,DXA)测定腰椎前后位腰1至腰4、股骨颈面积骨密度(bone mineral density,BMD)、T值和Z值。测定外周血以下指标的水平并进行相关性分析:OPG、RANKL、骨吸收标志物抗酒石酸酸性磷酸酶5b(tartrate-resistant acid phosphatase-5b,TRAP-5b)、骨形成标志物骨特异性碱性磷酸酶(bone-specific alkaline phosphatase,BAP)、总抗氧化能力(total antioxidant capacity,TAOC)、肿瘤坏死因子(tumor necrosis factor-α,TNF-α)和白细胞介素-6(interleukin-6,IL-6)。结果OSAHS组骨质疏松风险评估问卷阳性率为79%,对照组为39%。腰椎BMD对照组为(1.03±0.10)g/cm^(2)、OSAHS组为(0.95±0.11)g/cm^(2),股骨颈BMD OSAHS组为(0.84±0.13)g/cm^(2),对照组为(0.96±0.12)g/cm^(2),两组比较差异有统计学意义(P<0.05)。与对照组相比,OSAHS组股骨颈和腰椎T值、Z值减低(P<0.05)。与对照组比较,OSAHS组OPG、OPG/RANKL比值、BAP、TAOC水平分别为(31.38±23.00)μg/L、8.16±7.10、(15.62±5.20)μg/L、(6.23±1.30)U/mL;均较对照组下降,TNF-α和IL-6水平分别为53.95(20.08~176.09)ng/L、29.66(17.86~62.28)ng/L,均较对照组升高。OSAHS组TRAP-5b水平为(3.44±1.00)U/L,与对照组比较差异无统计学意义(P<0.05)。OSAHS轻中度组和重度组股骨颈和腰椎BMD、T值和Z值、RANKL、OPG、OPG/RANKL,TRAP-5b和BAP、TNF-α和IL-6比较差异均无统计学意义(P>0.05)。OSAHS患者年龄<50岁组OPG、OPG/RANKL比值、BAP分别为(33.39±21.02)μg/L、11.68±8.69和(15.85±4.71)μg/L,≥50岁组为(26.37±19.90)μg/L、6.56±5.71和(12.13±6.23)μg/L,两组间比较差异有统计学意义(P<0.05),股骨颈和腰椎BMD及T值、RANKL、TRAP-5b、TNF-α和IL-6比较,差异均无统计学意义(P>0.05)。OSAHS组血清TAOC和BAP呈正相关(r=0.248,P=0.040),OPG和BAP呈正相关(r=0.267,P=0.030)。结论OSAHS存在骨代谢调节系统OPG/RANKL比例失衡,骨形成标志物水平下降,出现骨代谢异常;氧化应激反应增强使抗氧化能力下降,与OPG/RANKL失衡存在一定相关性。 展开更多
关键词 阻塞性睡眠呼吸暂停低通气综合征 骨质疏松 骨保护素 核因子κ-B受体活化因子配体 氧化应激 系统性炎性反应
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A dangerous combination: tuberculosis and chronic obstructive pulmonary disease 被引量:3
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作者 sun yong-chang 《Chinese Medical Journal》 SCIE CAS CSCD 2013年第12期2203-2204,共2页
oth chronic obstructive pulmonary disease (COPD) and pulmonary tuberculosis are leading causes of morbidity and mortality, and theretbre the most important challenges to public health in China. A large, populationba... oth chronic obstructive pulmonary disease (COPD) and pulmonary tuberculosis are leading causes of morbidity and mortality, and theretbre the most important challenges to public health in China. A large, populationbased survey showed that the prevalence of COPD was 8.2% (men, 12.4%; women, 5.1%) in adults 40 years of age or older,1 and even higher in Chinese rural areas where biomass fuels are the main sources of energy for cooking, 展开更多
关键词 TUBERCULOSIS chronic obstructive pulmonary disease
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Taking ACTion for better control of asthma 被引量:2
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作者 sun yong-chang 《Chinese Medical Journal》 SCIE CAS CSCD 2007年第12期1035-1036,共2页
The global prevalence of asthma ranges from 1% to 18% of the population in different countries. In China, while national data of asthma prevalence are still lacking, an epidemiological study in Beijing showed that the... The global prevalence of asthma ranges from 1% to 18% of the population in different countries. In China, while national data of asthma prevalence are still lacking, an epidemiological study in Beijing showed that the prevalence of asthma in occupational populations was 1.25%. Based on epidemiological data reported in different regions, it is estimated that 15-20 million people suffer from asthma in the mainland of China,^4 and its prevalence continues to rise. A national epidemiological study of childhood asthma in the year of 2000 showed that the prevalence of asthma in urban children under the age of 14 years was 0.12%-3.34% in different regions, 展开更多
关键词 ASTHMA asthma disease management
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Advances in respiratory medicine in the mainland of China: a historical perspective 被引量:1
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作者 sun yong-chang 《Chinese Medical Journal》 SCIE CAS CSCD 2010年第1期6-17,共12页
For the first 10 years after the founding of the People's Republic of China in 1949, the study of respiratorydiseases was focused on pulmonary tuberculosis which severely threatened people's health. Doctors who spec... For the first 10 years after the founding of the People's Republic of China in 1949, the study of respiratorydiseases was focused on pulmonary tuberculosis which severely threatened people's health. Doctors who specialized in tuberculosis also took care of patients with other lung diseases. In 1953, Chinese Journal of Tuberculos&, the official journal of the China Tuberculosis Association, was inaugurated; and it was renamed Chinese Journal of Tuberculosis and Respiratory Diseases in 1978. Just as Wu and others1 stated in 1959 in the review article A summary of the studies of respiratory diseases in China of the past 10 years, published in the Chinese Journal of Internal Medicine (C JIM), "among a variety of respiratory diseases, pulmonary tuberculosis was the most common, accounting for about 80%. According to the publications collected, other common respiratory diseases also included pneumonia, bronchiectasis, tuberculous pleurisy, lung abscess, lung cancer, parasitic infections, silicosis, pneumothorax and fungal infections... 展开更多
关键词 respiratory disease HISTORY China
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Chronic obstructive pulmonary disease in primary healthcare institutions in China: Challenges and solutions 被引量:1
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作者 sun yong-chang 《Chronic Diseases and Translational Medicine》 CSCD 2020年第4期219-223,共5页
Chronic obstructive pulmonary disease(COPD)is a preventable and treatable condition characterized by persistent respiratory symptoms and airflow limitation.It usually results from airway and/or alveolar abnormalities ... Chronic obstructive pulmonary disease(COPD)is a preventable and treatable condition characterized by persistent respiratory symptoms and airflow limitation.It usually results from airway and/or alveolar abnormalities caused by exposure to noxious particles or gases.1 The burden of respiratory diseases,most commonly COPD,ranks third among all systemic diseases in China.2 In the latest epidemiological survey,the prevalence rate of COPD in rural areas was significantly higher than that in urban areas(9.6%vs.7.4%).3 Furthermore,most patients with COPD first visit primary healthcare institutions.However,the overall prevention and treatment standard for COPD at the primary level in China is not promising.4,5,6 This study aimed to introduce and present challenges in the prevention and treatment of COPD based on the relevant literature to improve the knowledge of and attention on healthcare-related treatment and prevention for COPD. 展开更多
关键词 Chronic obstructive pulmonary disease Primary healthcare Primary guidelines China
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Chronic obstructive pulmonary disease in China: a tale of two people 被引量:1
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作者 sun yong-chang 《Chinese Medical Journal》 SCIE CAS CSCD 2010年第12期1491-1493,共3页
The term chronic obstructive pulmonary disease (COPD) has been well known and the diseaseextensively studied for more than a decade in China, but only recently has great progress been made in the epidemiology and ma... The term chronic obstructive pulmonary disease (COPD) has been well known and the diseaseextensively studied for more than a decade in China, but only recently has great progress been made in the epidemiology and management of this highly prevalent disease in this country. Historically, beginning in the early 1960s, long before the definition of COPD was widely accepted, a great number of studies that included traditional Chinese medicine had been performed on chronic bronchitis, emphysema, and related respiratory failure and cor pulmonale. 展开更多
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