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吉林大学学报（工学版） 2006年第4期36卷 502-505页

作者：李雯高峰孙鹏北京航空航天大学汽车工程系北京100083

运用地面力学与高等土力学的相关知识,对给定土壤参数的刚性轮-土壤的相互作用做了定性分析,获得了探测车行驶阻力与其所受的垂直载荷的相互关系。根据分析结果,提出了利用低密度的夹层复合材料制造探测车车轮的设计思想。

关键词：车辆工程深空探测车地面力学夹层材料车轮设计

静载下Y/YY型管节点构件的AE特征信号分析

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塑性工程学报 2022年第12期29卷 209-216页

作者：王朋飞石健西南石油大学机电工程学院四川成都610500

针对导管架式海洋平台中Y/YY型管节点在海洋环境中由于腐蚀缺陷造成承载力降低的问题,对含腐蚀缺陷和用碳纤维复合材料(CFRP)加固后含腐蚀缺陷的两种类型Y/YY型管节点进行了静载轴压试验,并使用声发射技术采集了压缩过程中的声发射特征... 详细信息

针对导管架式海洋平台中Y/YY型管节点在海洋环境中由于腐蚀缺陷造成承载力降低的问题,对含腐蚀缺陷和用碳纤维复合材料(CFRP)加固后含腐蚀缺陷的两种类型Y/YY型管节点进行了静载轴压试验,并使用声发射技术采集了压缩过程中的声发射特征参数。通过比较声发射的振铃计数、能量计数等参数,并结合构件的载荷-位移曲线对构件的承载能力进行了研究。结果表明,声发射振铃计数、累积能量计数与材料的应力-应变曲线的变化规律趋势相同,能够较好地反映材料在载荷作用下的变形规律。管节点构件在静载中的声发射振铃计数和能量计数的变化趋势能够体现构件在载荷作用下的变形和损伤程度。经CFRP加固的构件在静载下突发型信号降低,表明管节点构件的变形较小,相应的承载力提高。

关键词：声发射腐蚀缺陷管节点轴压承载力

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马齿苋黄酮抗衰老作用研究（英文）

天然产物研究与开发 2017年第6期29卷 988-993页

作者：尹爱武高鹏飞党丽敏湖南工程学院化学化工学院湘潭411104 大理大学药学院大理671000

本文研究马齿苋黄酮的抗衰老作用。给药(FPO)6周后测定血清、肝和脑组织谷胱甘肽过氧化物酶(GSH-Px)和超氧化物歧化酶(SOD)的活力,丙二醛(MDA)的含量及小鼠胸腺和脾脏指数。水迷宫试验与跳台试验测定马齿苋黄酮对衰老小鼠学习与记忆能... 详细信息

本文研究马齿苋黄酮的抗衰老作用。给药(FPO)6周后测定血清、肝和脑组织谷胱甘肽过氧化物酶(GSH-Px)和超氧化物歧化酶(SOD)的活力,丙二醛(MDA)的含量及小鼠胸腺和脾脏指数。水迷宫试验与跳台试验测定马齿苋黄酮对衰老小鼠学习与记忆能力的影响。结果显示马齿苋黄酮能显著增加小鼠胸腺和脾脏指数,显著增强血清、肝和脑组织GSH-Px和SOD活力及显著减少其中MDA含量。马齿苋黄酮能显著减少水迷宫试验中小鼠的逃避潜伏期及跳台试验中反应时间与错误次数;显著增加水迷宫试验中小鼠的穿越次数与跳台试验中的记忆潜伏期。马齿苋黄酮有显著的抗衰老作用。

关键词：马齿苋水迷宫超氧化物歧化酶丙二醛谷胱甘肽过氧化物酶

基于LCC的磁谐振无线电能传输发射端补偿技术

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电工技术学报 2016年第A01期31卷 9-15页

作者：高键鑫吴旭升高嵬彭威海军工程大学电气工程系武汉430033

为实现磁耦合谐振式无线电能传输系统最大化功率传输,提升整机效率,提出了一种基于LCC三阶补偿网络结构的保持发射端线圈电流恒定的方法,此方法不受接收端反射阻抗影响,实现了电磁感应式无线电能传输(ICPT)系统发射端与接收端解耦设计... 详细信息

为实现磁耦合谐振式无线电能传输系统最大化功率传输,提升整机效率,提出了一种基于LCC三阶补偿网络结构的保持发射端线圈电流恒定的方法,此方法不受接收端反射阻抗影响,实现了电磁感应式无线电能传输(ICPT)系统发射端与接收端解耦设计。同时,提出了LCC补偿网络的数学模型及其参数设计方法。在不增加元件的情况下,采用LCC网络的输入基波电流补偿LCC网络的输入高次谐波电流的方法,在功率管关断瞬间,降低通过功率管的电流瞬时值,实现了高频逆变器的零电流关断,减小了功率管的开关损耗和开关应力,提高了ICPT系统的整体效率。最后,对所提方法进行了仿真分析和实验验证。仿真和实验结果验证了所提模型和参数设计方法的正确性和可行性。

关键词：电磁感应式无线电能传输磁耦合 LCC 谐振

Carinatines A and B,Lycopodium Alkaloids from Phlegmariurus carinatus

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Natural Products and Bioprospecting 2014年第4期4卷 221-225页

作者： fei Liu Yu-Cheng Liu Wei-Wei Jiang Juan He Xing-De Wu Li-Yan peng Jia Su Xiao Cheng Qin-Shi Zhao State Key Laboratory of Phytochemistry and Plant Resources in West China Kunming Institute of BotanyChinese Academy of ScienceKunming 650201People’s Republic of China University of the Chinese Academy of Sciences Beijing 100049People’s Republic of China

Carinatine A(1),a C16N2-type Lycopodium alkaloid possessing a 5/6/6/6 ring system formed by a new C-4/C-12 bond,and carinatine B(2),the first derivative of lycojaponicumin C,along 16 known compounds,were isolated from the whole plant of Phlegmariurus *** structures were elucidated based on the spectroscopic *** two new isolates were no inhibitory activity for the acetylcholinesterase(AChE).

关键词： Lycopodium alkaloid Phlegmariurus carinatus Carinatines A and B Acetylcholinesterase(AChE)inhibitory activity

Processes of runoff in seasonally-frozen ground about a forested catchment of semiarid mountains

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Research in Cold and Arid Regions 2020年第5期12卷 272-283页

作者： pengfei Lin ZhiBin He Jun Du Longfei Chen Xi Zhu QuanYan Tian Linze Inland River Basin Research Station Chinese Ecosystem Research NetworkLanzhouGansu 730000China Key Laboratory of Ecohydrology of Inland River Basin Northwest Institute of Eco‐Environment and ResourcesChinese Academy of SciencesLanzhouGansu 730000China

Climate warming increases the variability in runoff of semiarid mountains where seasonally-frozen ground is widely ***,what is not well understood are the processes of runoff,hydrological drivers,and freeze-thaw cycles in seasonally-frozen ground in semiarid *** understand how freeze-thaw cycles affect runoff processes in seasonally-frozen ground,we monitored hydrological processes in a typical headwater catchment with seasonally-frozen ground in Qilian Mountain,China,from 2002 to *** analyzed the responses of runoff to temperature,precipitation,and seasonally-frozen ground to quantify process characteristics and driving *** results show that annual runoff was 88.5 mm accounting for 25.6%of rainfall,mainly concentrated in May to October,with baseflow of 36.44 *** runoff occurred in June,August,and September,i.e.,accounting for spring and summer *** during the spring flood was produced by a mix of rainfall,melting snow,and melting seasonally-frozen ground,and had a significant correlation with air *** was mainly due to precipitation accumulation during the summer *** temperature,average soil temperature at 0−50 cm depth,and frozen soil depth variable explained 59.60%of the variation of runoff in the thawing period,while precipitation variable explained 21.9%.Thawing-period runoff and soil temperature had a>0.6 correlation coefficient(P<0.05).In the rainfall-period,runoff was also affected by temperature,soil moisture,and precipitation,which explained 33.6%,34.1%and 18.1%,*** results show that increasing temperature and precipitation will have an irreversible impact on the hydrological regime in mountainous basins where seasonally-frozen ground is widely distributed.

关键词： runoff seasonally-frozen ground semiarid mountains Northeast margin of Tibetan Plateau

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梯形巷道近场区电磁波传播机制的分界点

煤炭技术 2015年第9期34卷 331-332页

作者：王利超成凌飞高鹏飞河南理工大学电气工程与自动化学院河南焦作454000

为精确地描述梯形巷道近场区传播特性,利用传播理论与空间立体几何,建立近场区自由空间传播机制与多模波导传播机制分界点的近似数学模型,推导出了收发天线安装在不同位置时分界点位置的计算公式;并讨论了天线安装位置、巷道高度对分界... 详细信息

为精确地描述梯形巷道近场区传播特性,利用传播理论与空间立体几何,建立近场区自由空间传播机制与多模波导传播机制分界点的近似数学模型,推导出了收发天线安装在不同位置时分界点位置的计算公式;并讨论了天线安装位置、巷道高度对分界点的影响。

关键词：梯形巷道近场区多模波导分界点

Application of Al techniques in monitoring and operation of power systems

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Frontiers in Energy 2019年第1期13卷 71-85页

作者： David Wenzhong gao Qiang WANG Fang ZHANG Xiaojing YANG Zhigang HUANG Shiqian MA Qiao LI Xiaoyan GONG fei-Yue WANG University of Denver DenverCO 80210USA China State Key Laboratory of Power System Department of Electrical EngineeringTsinghua UniversityBeijing 100084China State Grid Tianjin Electric Power Company Tianjin 300010China State Grid Tianjin Electric Power Research Institute Tianjin 300384China Chinese Academy of Sciences(SKL-MCCS CASIA)Beijing 100190China

In recent years,the artificial intelligence(Al)technology is becoming more and more popular in many areas due to its amazing ***,the application of Al techniques in power systems is still in its ***,in this paper,the application potentials of Al technologies in power systems will be discussed by mainly focusing on the power system operation and *** the power system operation,the problems,the demands,and the possible applications of Al techniques in control,optimization,and decision making problems are ***,the fault detection and stability analysis problems in power system monitoring are *** the end of the paper,a case study to use the neural network(NN)for power flow analysis is provided as a simple example to demonstrate the viability of Al techniques in solving power system problems.

关键词： power system operation and monitoring artificial intelligence(Al) deep learning power flow analysis

Motif Discovery and Phylogenetic Analysis of Hepatitis B Virus Sequences

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Chinese Journal of Biomedical Engineering(English Edition) 2016年第3期25卷 121-126页

作者： ZHANG Qi ZHANG Jun-peng gao Jian-mei HE Jian-feng YAN Xin-min MA Lei LI Jiu-yong Kunming University of Science and Technology Yunnan Province Kunming 650504China Institute of Basic Medicine of the First People's Hospital of Yunnan Province and Center of Clinical Molecular Biologyand Kunhua Affiliated Hospital of Kunming Medical College Yunnan Province Kunming 650032China

Hepatitis B virus(HBV) infection is a severe global health problem. In recent years, mutations as an essential element in the HBV evolution have been extensively studied. However, the study of the conserved sequence for the evolution of HBV is still in its infancy. In this paper, we applied MEME(multiple EM for motif elicitation) algorithm for motif discovery and proposed a new metric CI(conserved index) to make phylogenetic analysis of HBV sequences. Our results indicate that MEME can efficiently discover multiple motifs from HBV sequences and the new measurement CI for the conservative of sequences can effectively help us to build the phylogenetic ***, we can get evolutionary relationship of HBV sequence through the phylogenetic tree.

关键词： motif discovery HBV phylogenetic tree conserved index evolution-ary relationship

Development patterns of adenoids in Chinese children without sleep-disordered breathing: a retrospective magnetic resonance imaging study with consecutive age groups

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Chinese Medical Journal 2021年第12期134卷 1500-1502页

作者： Xiao-Li Yi Un-Yin Yao peng-fei Zhao Xin-Yu Yuan Zhen-Chang Wang Department of Radiology The Affiliated Children's HospitalCapital Institute of PediatricsBeijing 100020China Department of Otolaryngology Head and Neck Surgery Beijing Anzhen HospitalCapital Medical UniversityBeijing 100029China Department of Radiology Beijing Friendship HospitalCapital Medical UniversityBeijing 100050China

To the Editor:Sleep-disordered breathing(SDB)is a health problem affecting approximately 12%of children in China,[1]characterized by habitual loud snoring and increased respiratory *** upper airway resistance related to enlarged adenoids has been identified as the most common cause in children with obstructive SDB,and adenoidectomy is the standard treatment for the *** to lymphoid tissues,adenoids show a unique natural growth pattern,which incorporates both overgrowth and ***,the development patterns of adenoids have not been clearly *** the adenoids are located in the nasopharynx roof,direct evaluation of their size and proportion to the upper airway area is ***,radiological methods have been employed widely for such purposes,including traditional plain cranial radiographs,computed tomography(CT),cone-beam CT,and magnetic resonance imaging(MRI).MRI can reveal the accurate size of adenoids by differentiating them from other soft tissue structures without any ionizing radiation;therefore,it can effectively study the adenoids’developmental pattern in normal *** studies have evaluated age-associated changes in adenoid size by *** et al[2]indicated that adenoids grow proportionally to the skeletal structures in children aged 1 to 11 *** et al[3]reported that head MRI examinations demonstrated increased adenoid size during the first 7–8 years of life and then decreased gradually in children without snoring *** of the above-reported adenoids’development pattern exist due to the limitations associated with the small sample ***,none of the above-mentioned studies on normal children used a strict method to exclude ***,for adenoid hypertrophy,the adenoid/nasopharyngeal(A/N)ratio was found to be a useful,tolerable,and confident diagnostic method in pediatric patients,with emphasis on the correlation of the adenoid size and upper airway lu

关键词： adenoid resonance children