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A deep kernel method for lithofacies identification using conventional well logs

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Petroleum Science 2023年第3期20卷 1411-1428页

作者： Shao-Qun Dong zhao-Hui zhong Xue-Hui Cui Lian-Bo Zeng Xu Yang Jian-jun Liu Yan-Ming Sun jing-Ru Hao State Key Laboratory of Petroleum Resources and Prospecting China University of PetroleumBeijing102249China Collge of Science China University of PetroleumBeijing102249China College of Geoscience China University of PetroleumBeijing102249China

How to fit a properly nonlinear classification model from conventional well logs to lithofacies is a key problem for machine learning *** methods(e.g.,KFD,SVM,MSVM)are effective attempts to solve this issue due to abilities of handling nonlinear features by kernel *** mining of log features indicating lithofacies still needs to be improved for kernel ***,this work employs deep neural networks to enhance the kernel principal component analysis(KPCA)method and proposes a deep kernel method(DKM)for lithofacies identification using well *** includes a feature extractor and a *** feature extractor consists of a series of KPCA models arranged according to residual network structure.A gradient-free optimization method is introduced to automatically optimize parameters and structure in DKM,which can avoid complex tuning of parameters in *** test the validation of the proposed DKM for lithofacies identification,an open-sourced dataset with seven con-ventional logs(GR,CAL,AC,DEN,CNL,LLD,and LLS)and lithofacies labels from the Daniudi Gas Field in China is *** are eight lithofacies,namely clastic rocks(pebbly,coarse,medium,and fine sand-stone,siltstone,mudstone),coal,and carbonate *** comparisons between DKM and three commonly used kernel methods(KFD,SVM,MSVM)show that(1)DKM(85.7%)outperforms SVM(77%),KFD(79.5%),and MSVM(82.8%)in accuracy of lithofacies identification;(2)DKM is about twice faster than the multi-kernel method(MSVM)with good *** blind well test in Well D13 indicates that compared with the other three methods DKM improves about 24%in accuracy,35%in precision,41%in recall,and 40%in F1 score,*** general,DKM is an effective method for complex lithofacies *** work also discussed the optimal structure and classifier for *** re-sults show that(m_(1),m_(2),O)is the optimal model structure and linear svM is the optimal classifier.(m_(1),m_(2),O)means there

关键词： Lithofacies identification Deepkernel method Well logs Residual unit Kernel principal component analysis Gradient-free optimization

Associations of early-life factors and indoor environmental exposure with asthma among children:a case-control study in Chongqing,China

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World Journal of Pediatrics 2022年第3期18卷 186-195页

作者： Yun-Tian Deng Xue-Mei Li En-Mei Liu Wen-Kui Xiong Shuo Wang Rui Zhu Yu-Bin Ding zhao-Hui zhong The First Clinical College Chongqing Medical UniversityChongqingChina Pediatric Outpatient Chongqing Health Center for Women and ChildrenChongqingChina National Clinical Research Center for Child Health and Disorders Ministry of Education Key Laboratory of Child Development and DisordersChongqing Key Laboratory of PediatricsChongqingChina Department of Respiratory Medicine Children’s Hospital of Chongqing Medical UniversityChongqingChina School of Public Health and Management Chongqing Medical UniversityChongqingChina School of Public Health and Management Research Center for Medicine and Social DevelopmentInnovation Center for Social Risk Governance in HealthChongqing Medical UniversityNo.1Medical School RoadYu zhong DistrictChongqingChina

Background Childhood asthma has substantial effects on children’s *** is important to identify influencing factors in early life in the development of childhood *** aim to evaluate the effects of early-life factors and indoor environmental exposure on childhood asthma in Chongqing,*** We designed a case-control study to enrol children with asthma aged 3 to<14 years old and controls in Chongqing,***“Children’s Early Life and Indoor Environment Survey”was used to collect the early-life factors and indoor environmental exposure of foetuses in utero and of infants during the first 3 years of life.A multivariate logistic regression model was used to evaluate the association between independent variables and childhood asthma and the interaction of early-life factors and environmental *** A total of 160 asthma cases and 247 controls were included in this *** mean ages of the cases and controls were 5.53±1.88 and 5.72±2.34 years,respectively(P=0.192).Early-life factors and indoor environmental exposure were independently associated with childhood *** diseases of the respiratory system in children under 3 years old[adjusted odds ratio(OR)=5.76,95%confidence interval(CI)2.49-13.30],bedroom air conditioner use(adjusted OR=4.61,95%CI 1.45-14.64),and bedroom dampness/mould(adjusted OR=2.98,95%CI 1.54-5.75)ranked as the three most significant exposures associated with the risk of childhood *** factors associated with an increased risk of childhood asthma included second-hand smoke exposure in early life(adjusted OR=1.93,95%CI 1.24-3.00),neonatal pneumonia(adjusted OR=1.90,95%CI 1.05-3.42)and maternal allergic diseases during pregnancy(adjusted OR=2.13,95%CI 1.10-4.10).The interaction effects of child second-hand smoke exposure with other covariates were not found to be statistically *** Early-life factors and indoor environmental exposure are closely related to childhood asthma in Chongqing,C

关键词： Asthma Children Environment Risk/protective factor

Superconductivity of Nd_(1.85)Ce_(0.15)CuO_(4-y) by Electrochemical Oxidation

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Chinese Physics Letters 2000年第8期17卷 601-602页

作者： CHEN Ling CHE GUANG-CAN LI Hong DONG Cheng ZHOU Fang Huang Yu-zhen zhao zhong-Xian National Laboratory for Superconductivity Institute of PhysicsChinese Academy of SciencesBeijing 100080 National Laboratory for Solid State Ionics Institute of PhysicsChinese Academy of SciencesBeijing 100080

Superconductivity of n-type superconductor Nd_(1.85)Ce_(0.15)CuO_(4-y)(NCCO)by electrochemical oxidation is re ported for the first time and the cyclic voltammogram curve for NCCO as working electrode is *** vestigations indicate that after oxidation,superconductivity of NCCO is improved:Tc is raised from 20 K up to 26 K,the superconducting volume fraction is increased *** valence electronic states of oxygen and copper in NCCO are studied by x-ray photoelectron *** is found that the Cu-2_(ps/2)peak shifts to the higher binding energy side about 0.4 e V,which indicates that the valence-state of copper ions is risen up after *** results imply that hole-carriers exist in n-type superconductor.

关键词： spectroscopy. copper Oxidation

Terahertz spectroscopy and lattice vibrational analysis of pararealgar and orpiment

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Chinese Physics B 2022年第10期31卷 384-388页

作者： Ya-Wei Zhang Guan-Hua Ren Xiao-Qiang Su Tian-Hua Meng Guo-zhong zhao Institute of History for the Science and Technology Inner Mongolia Normal UniversityHohhot 010022China School of Yungang Ology Shanxi Datong UniversityDatong 037009China Department of Mathematics and Physics North China Electric Power UniversityBaoding 071003China Institute of Solid State Physics Shanxi Provincial Key Laboratory of Microstructure Electromagnetic Functional MaterialsShanxi Datong UniversityDatong 037009China Department of Physics Capital Normal UniversityBeijing 100048China

Terahertz time-domain spectroscopy(THz-TDS)is an effective nondestructive and noninvasive tool for investigating sulfur-containing *** with Raman spectroscopy and vibrational mode analysis,it is significant for artifact identification and *** this work,the terahertz absorption spectra of pararealgar(As_(4)S_(4))and orpiment(As_(2)S_(3))samples mixed with polytetrafluoroethylene(PTFE)are characterized in a range from 0.2 THz to 2.2 THz,and their distinctive peaks are observed,***,qualitative analysis is also implemented by using Raman spectroscopy as a complementary *** lattice vibrations are simulated by using solid-state density functional theory(ss-DFT),illustrating different characteristic absorption peaks for specific crystalline structures and dynamic *** work provides a reliable database of sulfur-containing pigments for using the THz technology to actually analyze and diagnose cultural relics.

关键词： THz-TDS lattice vibrations solid-state density functional theory(ss-DFT) pararealgar orpiment

Signature Inversion of Yrast Band in Odd-Odd ^(162)Lu Nucleus

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Chinese Physics Letters 1996年第4期13卷 257-260页

作者： ZHANG Yu-hu ZHOU Xiao-hong zhao Qing-zhong SUN Xiang-fu LEI Xiang-guo GUO Ying-xiang LIU zhong CHEN Xing-feng ZHU Yong-tai WEN Shu-xian YUAN Guan-jun LIU Xiang-an Institute of Modern Physics Chinese Academy of Sciences Lanzhou 730000 China Institute of Atomic Energy Beijing 102413

High spin states of the odd-odd ^(162)Lu nucleus have been studied via ^(147)Sm(^(19)F,4nγ)reaction at 95MeV beam *** scheme for yrast band based on π[h_(11/2)]v[i_(13/2)]quasiparticle configuration was established up to I^(π)-(23^(-))for the first *** band shows the signature inversion in energy before backbending generally appeared in this mass *** is stressed that the signature splitting in 162Lu is larger than that in 160 Tm nucleus.

关键词： energy signature

Epitaxial Growth of Bi_(2)Sr_(2-x)LaxCu_(1)O_(6+δ) Thin Films by In-Situ dc Magnetron Sputtering

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Chinese Physics Letters 1998年第5期15卷 373-375页

作者： ZHANG Ying-zi YANG Duo-gui LI Lin zhao Bai-ru JIA Shun-lian CHEN Hong WU Fei CHE Guang-can zhao zhong-xian National Laboratory for Superconductivity Institute of Physics&Centre for Condensed Matter PhysicsChinese Academy of SciencesBeijing 100080

Bi_(2)Sr_(2-x)LaxCu_(1)O_(6+δ)(La-2201)thin films were successfully prepared on(100)SrTiO_(3) and(100)LaAIO_(3) substrates by in-situ dc-magnetron sputtering process.A series compensated 2201 targets of La^(3+)substitution contents for Sr^(2+)were studied for growing 2201 phase thin *** superconducting zero resistance temperature T_(c,0) reached 19K.X-ray diffraction analyses showed that films oriented with c-axis perpendicular to the substrate surface and their lattice parameters are around 2.43-2.46nm.Ф-scan and rocking curve show a good epitaxial growth and crystallisation of the films.

关键词： process. substitution perpendicular

Yield Evaluation of Twenty-Eight Alfalfa Cultivars in Hebei Province of China

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Journal of Integrative Agriculture 2014年第10期13卷 2260-2267页

作者： ZHANG Tie-jun KANG Jun-mei GUO Wen-shan zhao zhong-xiang XU Yu-peng YAN Xu-dong YANG Qing-chuan Institute of Animal Science Chinese Academy of Agricultural Sciences Cangzhou Technical College

Cultivar selection is important for alfalfa （Medicago sativa L.） hay production. From 2009 to 2012, a field study was conducted to evaluate the dry matter yield （DMY） of 28 cultivars in Cangzhou District of Hebei Province, China, and to determine the most suitable cultivars for this province and other zones with similar climate conditions. 28 alfalfa cultivars were sown in late March of 2009 and were harvested for hay four times in each subsequent year. The results showed that the climatic conditions resulted in significant differences in annual DMY among years, with the second year being the highest and the first year the lowest. The top five cultivars with the highest total DMY were L2750 （62.75 t ha^-1）, Hom （62.72 t ha^-1）, 86-266 （61.55 t ha^-1）, German （61.44 t ha^-1） and zhongmu 1 （61.18 t ha^-1）, respectively. Across all four years, first harvest had the highest ratios to annual DMY except the cultivar of Rambler, while the fourth harvest had the lowest ratio. There were positive correlation relationships between DMY of each harvest and annual DMY, and the correlation coefficients were all significant in four years. And the path coefficients of first harvest were always the highest in four years. The qualities showed small variations among these cultivars and the cultivar L3750 presented the highest crude protein in both years. Crude protein had significant positive correlation with relative feed value （RFV） in both years while crude fiber had significant negative correlation with RFV and crude fiber.

关键词： alfalfa cultivars yield forage quality

基于累积平方误差-总平方波动指标的模型预测控制器性能评价及自愈

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控制理论与应用 2021年第1期38卷 166-176页

作者：张浩赵众北京化工大学信息科学与技术学院北京100029

本文针对模型预测控制器实际投运中遇到性能下降问题,提出了一种基于累积平方误差(ISE)–总平方波动(TSV)指标的模型预测控制器性能评价及自愈方法.先基于累积平方误差(ISE)和总平方波动(TSV)指标对模型预测控制器进行实时性能评价,再... 详细信息

本文针对模型预测控制器实际投运中遇到性能下降问题,提出了一种基于累积平方误差(ISE)–总平方波动(TSV)指标的模型预测控制器性能评价及自愈方法.先基于累积平方误差(ISE)和总平方波动(TSV)指标对模型预测控制器进行实时性能评价,再根据无限时域模型预测控制器(MPC)的逆特性,基于ISE–TSV指标的分析,提出了一种MPC控制器的鲁棒自愈方法.在二级倒立摆的模型预测控制仿真与实验结果证明了所提自愈方法的可行性及有效性.

关键词：模型预测控制器控制器性能评价控制器参数自愈累积平方误差–总平方波动指标鲁棒性

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自适应扰动估计的相关积分优化方法及应用

控制理论与应用 2017年第7期34卷 956-964页

作者：陈杰赵众北京化工大学信息科学与技术学院北京100029

针对传统相关积分优化方法,当系统扰动与调优变量相关时,在迭代优化的过程中,目标函数难以收敛到最优值的问题,提出了一种改进的相关积分优化方法用于稳态操作调优.基于数据驱动稳态模型,构造了自适应扰动估计器用来估计扰动均值,对最... 详细信息

针对传统相关积分优化方法,当系统扰动与调优变量相关时,在迭代优化的过程中,目标函数难以收敛到最优值的问题,提出了一种改进的相关积分优化方法用于稳态操作调优.基于数据驱动稳态模型,构造了自适应扰动估计器用来估计扰动均值,对最小二乘方法计算得到的调优变量梯度均值进行补偿,并修正调优变量,确保目标函数在调优的过程中收敛于最优值.仿真对比及工业应用结果证实了所提方法的可行性和有效性.

关键词：稳态优化相关积分梯度估计扰动估计自适应