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孕11～13^(+6)w产前超声筛查胎儿严重心脏畸形的临床价值

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中国优生与遗传杂志 2016年第12期24卷 117-119,F0003页

作者：王颖金安培莉侯小霞张喻西北妇女儿童医院医学超声中心陕西西安710061

目的探讨11~13^(+6)w产前超声筛查软指标与胎儿心脏结构异常的关系。方法选取2014年2月至2015年6月在我院进行妊娠早期超声检查的孕妇1486例,经腹超声检查,记录NT值、三尖瓣反流(TR)及静脉导管血流a波(DV a波)倒置等超声软指标情况,计... 详细信息

目的探讨11~13^(+6)w产前超声筛查软指标与胎儿心脏结构异常的关系。方法选取2014年2月至2015年6月在我院进行妊娠早期超声检查的孕妇1486例,经腹超声检查,记录NT值、三尖瓣反流(TR)及静脉导管血流a波(DV a波)倒置等超声软指标情况,计算早孕期超声诊断心脏畸形的准确度、各项软指标诊断的灵敏度与特异度。结果 1486例胎儿共诊断胎儿心脏畸形42例,其中严重心脏畸形31例;NT厚度为95~99百分位胎儿61例(4.10%,61/1486),7例产前诊断为严重心脏畸形,其中5例在早孕期诊断,2例在中孕期诊断,诊断灵敏度为22.58%(7/31),特异度为3.63%(54/1486)。NT厚度>第99百分位胎儿15例(1.01%,15/1486),13例产前诊断为严重心脏畸形,其中10例为早期诊断,3例为中孕期诊断,诊断灵敏度为41.94%(13/31),特异度为0.13%(2/1486)。TR 17例(1.14%),DV a波倒置35例(2.35%),而在31例产前诊断严重心脏畸形胎儿中,有11例合并TR,诊断敏感度为35.48%(11/31),特异度为0.40%(6/1486);10例合并DV a波倒置,诊断敏感度为32.26%(10/31),特异度为1.68%(25/1486)。结论 NT增厚、TR和DV a波倒置能检出大部分严重心脏畸形,可以为临床更早诊断先天性心脏病提供依据。

关键词：颈项透明层三尖瓣反流静脉导管血流a波早孕期心脏结构异常

四波混频Autler-Townes分裂中的探测光影响

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原子与分子物理学报 2025年第3期42卷 110-115页

作者：裴丽娅侯海龙北京化工大学数理学院北京100029

在双Λ-型四波混频系统中,研究了探测光强度对Autler-Townes(AT)分裂效应的影响.随着弱探测光强度增大,由缀饰态共振产生的AT分裂双峰间隔不变,但却逐渐增宽线宽且减弱直至消失;而在强耦合光失谐条件下,不对称地位于单光子共振峰两侧的A... 详细信息

在双Λ-型四波混频系统中,研究了探测光强度对Autler-Townes(AT)分裂效应的影响.随着弱探测光强度增大,由缀饰态共振产生的AT分裂双峰间隔不变,但却逐渐增宽线宽且减弱直至消失;而在强耦合光失谐条件下,不对称地位于单光子共振峰两侧的AT分裂双峰却会逐渐趋于对称分布.详细讨论了探测光场对原子的缀饰影响,提出通过探测光强度可以调控原子两基态之间的有效Raman相干,从而影响AT分裂双峰的特征.

关键词：四波混频原子相干 Autler-Townes分裂缀饰态横向弛豫率

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加权支持向量回归算法

计算机科学 2003年第11期30卷 38-39页

作者：孙德山吴今培侯振挺肖健华中南大学铁道校区科学研究所五邑大学智能技术与系统研究所广东江门529020

1引言Vapnik等人根据统计学习理论提出的支持向量机学习方法[1],近年来受到了国际学术界的广泛重视.支持向量机的最大特点是根据Vapnik结构风险最小化原则,尽量提高学习机的泛化能力,即由有限的训练集样本得到的小的误差能够保证对独立... 详细信息

1引言Vapnik等人根据统计学习理论提出的支持向量机学习方法[1],近年来受到了国际学术界的广泛重视.支持向量机的最大特点是根据Vapnik结构风险最小化原则,尽量提高学习机的泛化能力,即由有限的训练集样本得到的小的误差能够保证对独立的测试集仍然保持小的误差.

关键词：加权支持向量回归算法人工智能优化形式模式识别

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课程思政融入初中语文的独特优势与实施策略

语言与文化研究

语言与文化研究 2025年第1期33卷 152-155页

作者：裴天娇侯菊云南大学昆明650500

“课程思政”虽缘起高校,但思政内容与各学科融合的教育意义却为全学段所通用,初中阶段是青少年成才成长的“拔节孕穗期”,而语文作为兼具工具性与人文性的学科,与课程思政理念的有效融合能够为培养担当大任的时代新人起到独特引领作用... 详细信息

“课程思政”虽缘起高校,但思政内容与各学科融合的教育意义却为全学段所通用,初中阶段是青少年成才成长的“拔节孕穗期”,而语文作为兼具工具性与人文性的学科,与课程思政理念的有效融合能够为培养担当大任的时代新人起到独特引领作用。本文立足于课程思政融入初中语文的独特优势,以初中语文课程的特点为圭臬,提出发挥教师引领作用、合理挖掘思政元素、改变以往授课方式等教学策略,以期为课程思政融入初中语文教学实践提供有效的改革思路。

关键词：课程思政初中语文独特优势实施策略

Adaptive fuze-warhead coordination method based on BP artificial neural network

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Defence Technology（防务技术） 2023年第11期29卷 117-133页

作者： Peng hou Yang pei Yu-xue Ge School of Aeronautics Northwestern Polytechnical UniversityXi'an710072ShaanxiChina

The appropriate fuze-warhead coordination method is important to improve the damage efficiency of air defense missiles against aircraft targets. In this paper, an adaptive fuze-warhead coordination method based on the Back Propagation Artificial Neural Network(BP-ANN) is proposed, which uses the parameters of missile-target intersection to adaptively calculate the initiation delay. The damage probabilities at different radial locations along the same shot line of a given intersection situation are calculated, so as to determine the optimal detonation position. On this basis, the BP-ANN model is used to describe the complex and highly nonlinear relationship between different intersection parameters and the corresponding optimal detonating point position. In the actual terminal engagement process, the fuze initiation delay is quickly determined by the constructed BP-ANN model combined with the missiletarget intersection parameters. The method is validated in the case of the single-shot damage probability evaluation. Comparing with other fuze-warhead coordination methods, the proposed method can produce higher single-shot damage probability under various intersection conditions, while the fuzewarhead coordination effect is less influenced by the location of the aim point.

关键词： Aircraft vulnerability Fuze-warhead coordination BP artificial neural network Damage probability Initiation delay

Solidification of Mg-Zn-Zr Alloys:Grain Growth Restriction,Dendrite Coherency and Grain Size

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Acta Metallurgica Sinica(English Letters) 2020年第11期33卷 1477-1486页

作者： pei Li Danhui hou En-hou Han Rongshi Chen Zhiwei Shan State Key Laboratory for Mechanical Behavior of Materials Xi'an Jiaotong UniversityXi'an 710049China Institute of Metal Research Chinese Academy of SciencesShenyang 110016China

The solidification characterization of Mg-xZn-0.5Zr(x=0,1,3,4,5 wt%)alloys has been extensively investigated through thermal analysis,microstructure characterization and thermodynamic *** impact of Zn content on the grain growth restriction,dendrite coherency and thus the final grain size has been investigated and *** Zn content,the grain size of Mg-xZn-0.5Zr alloy was firstly refined and then coarsened with the finest grain size of^50μm for the Mg-3 Zn-0.5 Zr(ZK31)*** effects of the grain size on the mechanical properties were observed in the investigated *** combination of growth restriction factor theory and dendrite coherency point provides a reasonable explanation of the grain size *** helps to further understand the mechanisms of grain refinement and grain coarsening related to solute content,providing reference for alloy design and grain size prediction.

关键词： Magnesium alloy Grain size Solute content Growth restriction Dendrite coherency Solidifi cation

Transport of Propylene Carbonate-LiTFSI Electrolytes in P(VDF-HFP)Using Time-resolved ATR-FTIR Spectroscopy:Diffusion Coefficients and Molecular Interactions

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Chinese Journal of Polymer Science 2021年第8期39卷 975-983,I0005页

作者： Hui-Xian Li Lei hou pei-Yi Wu National Engineering Research Center for Dyeing and Finishing of Textiles College of ChemistryChemical Engineering and BiotechnologyDonghua UniversityShanghai 201620China

The time-resolved attenuated total reflectance-Fourier transform infrared(ATR-FTIR)spectroscopy is employed to investigate the transport mechanism of gel electrolytes by monitoring the diffusion behavior of propylene carbonate-lithium bis(trifluoromethylsulfonyl)imide(PC-LiTFSI)solution through poly(vinylidene fluoride-co-hexafluoropropylene)(P(VDF-HFP))*** behavior has been observed for both TFSr and *** temperature leads to faster diffusion of TFSI'and PC,which could be related to the increased free volume in P(VDF-HFP)matrix and rapid molecular movements upon *** molecular interactions among LiTFSI,PC and P(VDF-HFP)have been *** the diffusion process,PC molecules,in the form of small clusters,can firstly diffuse through the P(VDF-HFP)film and interact with P(VDF-HFP)by dipole-dipole interaction,acting as the ***,Li+diffuses into P(VDF-HFP)with the help of ion-dipole interactions between Li+and C=0 of ***,TFSI-diffuses through the polymer matrix in solvation *** addition,slight ion-dipole interactions between Li+and P(VDF-HFP)have been observed as *** in this work contribute to a better understanding of transport process in gel polymer electrolytes for lithium-ion batteries and support the development of improved gel polymer electrolytes by rationally regulating molecular interactions.

关键词： ATR-FTIR spectroscopy Gel polymer electrolyte Transport mechanism Molecular interaction Diffusion coefficient

Terminal attitude selection method of missile attack aircraft

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Chinese Journal of Aeronautics 2024年第2期37卷 385-400页

作者： Peng hou Yang pei Yuxue GE Mengjie ZHU School of Aeronautics Northwestern Polytechnical UniversityXi’an 710072China Research Department Shanghai Electro-Mechanical Engineering InstituteShanghai 201108China

The appropriate terminal attitude of missile is important to improve the damage effectiveness of fragmentation warhead against aircraft *** this paper,three missile terminal attitude selection methods are proposed to solve the problem of terminal attitude selection in different situations according to their respective evaluation *** MVE-based method uses the damage probability of each detonation point around the aircraft at a given attitude of missile to calculate the Mean Volume of Effectiveness(MVE)at the corresponding attitude,and then uses the MVE for different attitudes to select the terminal strike *** detonation position-based method addresses the case where the missile detonation position can be assessed in *** the effects of missile guidance errors and fuze activation position errors,Monte Carlo simulations are used to calculate the damage probability of aircraft with different strike attitudes,from which the terminal strike attitude is *** BP-ANN model-based method uses the constructed Back Propagation Artificial Neural Network(BP-ANN)model instead of simulation to calculate the evaluation indexes in the corresponding cases of MVE-based method and Detonation position-based method,which can improve the efficiency of attitude *** are conducted for different scenarios to verify the feasibility and effectiveness of the proposed method.

关键词： Aircraft vulnerability Attitude selection BP-ANN Damage probability Damage effectiveness

Vertical-horizontal coupling nonlinear vibration characteristics of rolling mill under mixed lubrication

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Journal of Iron and Steel Research International 2021年第5期28卷 574-585页

作者： Dong-xiao hou Liang Xu pei-ming Shi School of Control Engineering Northeastern University at QinhuangdaoQinhuangdao 066004HebeiChina School of Electrical Engineering Yanshan UniversityQinhuangdao 066004HebeiChina

Considering the dynamic influence of the roll vibration on the lubricant film thickness in the rolling deformation area,nonlinear dynamic rolling forces related to film thickness in the vertical and horizontal directions were obtained based on the Karman balance *** on these dynamic rolling forces and the mechanical vibration of the rolling mill,a vertical-horizontal coupling nonlinear vibration dynamic model was *** amplitude-frequency equation of the main resonance was derived by using the multiple-scale *** last,the parameters of the 1780 rolling mill were used for numerical simulation,and the time-domain response curves of the system’s vibration displacement and lubricating film thickness under the steady and unsteady conditions were *** influences of parameters such as interface contact ratio,nonlinear parameters and external disturbances on the primary resonance frequency characteristics were obtained,which provided a theoretical reference for the suppression of rolling mill vibration.

关键词： Vertical-horizontal coupling Nonlinear vibration Mixed lubrication Dynamic rolling force Main resonance Amplitude-frequency characteristic