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Analysis of the periodic solutions of a smooth and discontinuous oscillator

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Acta Mechanica Sinica 2013年第4期29卷 575-582页

作者： Zhi-Xin li Qing-Jie Cao Marian Wiercigroch Alain Léger Centre for Nonlinear Dynamics Research Harbin Institute of Technology School of Astronautics Centre for Applied Dynamics Research School of Engineering University of Aberdeen King's College Laboratoire de Mécanique et d' Acoustique CNRS 31 Chemin Joseph Aiguier 13402 Marseille Cedex 20 France

In this paper, the periodic solutions of the smooth and discontinuous （SD） oscillator, which is a strongly irra- tional nonlinear system are discussed for the system having a viscous damping and an external harmonic excitation. A four dimensional averaging method is employed by using the complete Jacobian elliptic integrals directly to obtain the perturbed primary responses which bifurcate from both the hyperbolic saddle and the non-hyperbolic centres of the un- perturbed system. The stability of these periodic solutions is analysed by examining the four dimensional averaged equa- tion using Lyapunov method. The results presented herein this paper are valid for both smooth （e 〉 0） and discontin- uous （ce = 0） stages providing the answer to the question why the averaging theorem spectacularly fails for the case of medium strength of external forcing in the Duffing system analysed by Holmes. Numerical calculations show a good agreement with the theoretical predictions and an excellent efficiency of the analysis for this particular system, which also suggests the analysis is applicable to strongly nonlinear systems.

关键词： SD oscillator ~ Averaging method. Periodic so-lution ~ Irrational nonlinearity ~ Elliptic integral

A Dietary Supplement Jinghuosu Ameliorates Reproductive Damage Induced by Tripterygium Glycosides

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Chinese Journal of Integrative Medicine 2024年第4期30卷 330-338页

作者： MA Jing SUN Bo TE li-ger HUANG Xin ZUO Xin HAN Xiao-ke WANG Shu-song Hebei Key Laboratory of Reproductive Medicine Hebei Institute of Reproductive HealthHebei Reproductive Health HospitalShijiazhuang(050071)China Graduate School of Hebei Medical University Shijiazhuang(050017)China School of Chemistry and Materials Science Hebei Normal UniversityShijiazhuang(050024)China Xingtai Infertility Specialist Hospital XingtaiHebei Province(054000)China

Objective To determine the possible protective effects of Jinghuosu,a dietary supplement(DS),on tripterygium glycosides(TG)-induced reproductive system injury in rats and its underlying *** A reproductive damage model was established in rats by feeding of ***-eight male Sprague Dawley rats were randomly divided into 4 groups using a random number table(n=7 in each):control(C)group,model(M)group,DS group and L-carnitine(LC)*** in M,DS and LC groups received 40 mg/kg TGs *** from the 5th week,after administration of TGs for 4 h every day,rats in DS and LC groups were administered with 2.7 g/kg DS and 0.21 g/kg LC,respectively,for protective treatment over the next 4 *** in Group C continued to receive the control ***-eosin staining was used for histopathological analysis of rat testicular ***-linked immunosorbent assay was performed to measure alkaline phosphatase(ALP),lactate dehydrogenase,alcohol dehydrogenase,total antioxidant capacity(T-AOC),superoxide dismutase,glutathione peroxidase(GSH-Px),and malondialdehyde(MDA)*** assay was used to determine the serum testosterone *** real-time PCR and Western blotting were conducted to analyze the expression of genes and proteins related to the testosterone synthesis pathway and the nuclear factor erythroid 2-related factor 2/heme oxygenase 1 antioxidant *** Oral administration of TGs induced significant increases in the testicular levels of zinc transporter 1 and MDA(Plity,and serum testosterone,serum zinc,testicular zinc,Zrt-,Irt-like protein 1,ALP,luteinizing hormone(LH)receptor,steroidogenic acute regulatory protein,Cytochrome P450 family 11 subfamily A member 1,3β-hydroxysteroid dehydrogenase 1 T-AOC,GSH-Px,nuclear factor erythroid 2-related factor 2,heme oxygenase-1 and NAD(P)H:quinone oxidoreductase 1 levels decreased following TG

关键词： dietary supplement Jinghuosu tripterygium glycosides reproductive damage infertility

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用蒙特卡罗哈密顿量方法研究非S态

高能物理与核物理 2005年第7期29卷 717-720页

作者：黄纯青黎永耀罗向前 H.Krger 中山大学物理系佛山科学技术学院光电子与物理学系佛山528000 华南农业大学应用物理系广州510642 Département de Physique Université Laval Québec PQ G1K 7P4 Canada

以氢原子为例,验证了MonteCarloHamiltonian(MCH)方法推广应用到量子力学系统中在原点发散的势的非S态的有效性,给出估计误差的新思路,得到和解析解相符的能谱和约化径向波函数.

关键词：哈密顿量蒙特卡罗量子力学系统径向波函数推广应用估计误差氢原子新思路发散原点约化能谱

不同类型风电机组对小干扰和暂态稳定性的影响

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电力系统自动化 2013年第17期37卷 23-29,135页

作者：和萍文福拴薛禹胜 Ledwich ger ARD 李思岑华南理工大学电力学院广东省广州市510640 郑州轻工业学院电气信息工程学院河南省郑州市450002 浙江大学电气工程学院浙江省杭州市310027 南瑞集团公司(国网电力科学研究院) 江苏省南京市210003 澳大利亚昆士兰科技大学

随着风电装机容量在电力系统中渗透率的逐步提高,其对电力系统的影响越来越明显。这样,就很有必要系统地分析风电机组对电力系统小干扰和暂态稳定性的影响,以便研究针对性措施。在此背景下,对3类常见的风电机组接入后的电力系统稳定性... 详细信息

随着风电装机容量在电力系统中渗透率的逐步提高,其对电力系统的影响越来越明显。这样,就很有必要系统地分析风电机组对电力系统小干扰和暂态稳定性的影响,以便研究针对性措施。在此背景下,对3类常见的风电机组接入后的电力系统稳定性进行了系统的比较研究。首先给出了这3类风电机组的动态模型,之后以美国西部联合电力系统(WSCC)3机9节点系统为例,采用特征值分析和动态时域仿真方法,系统地比较了在同一母线接入异步风电机组、双馈风电机组、永磁直驱风电机组与接入同等容量同步发电机组对小干扰稳定和暂态稳定性的影响。研究结果表明,3类风电机组并网对小干扰稳定和暂态稳定性的影响程度均有所不同。

关键词：电力系统风电并网风电机组小干扰稳定暂态稳定

A SDUDY OF NEUROPHYSIOLOGICALLY COMPUTATIONAL MODEL FOR SPEECH PRODUCTION

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A SDUDY OF NEUROPHYSIOLOGICALLY COMPUTATIONAL MODEL FOR SPEE...

DFT Studies on the Complexation of Neptunyl by Acetate

第十三届全国人机语音通讯学术会议(NCMMSC2015)

作者： Bogu li Zhilei liu Jianwu Dang Bernd Kr?ger Tianjin Key Lab.of Cognitive Computing and Application Department of Phoniatrics Pedaudiology and Communication Disorders Medical School RWTH Aachen University

In this paper, we propose a neurophysiologically computational model with a physio-logical articulatory model to simulate the entire neurophysiological process of speech production. Firstly, a set of speech data for vowels and consonant-vowel(CV) syllables was generated using the physiological articulatory model driven by muscle activations;and then, the generated dataset was used as training data to learn four self-organizing maps(SOMs):speech planning, motor control, auditory feedback, and somatosensory feedback. Experimental results demonstrate that the implementation of the physiological articulatory model in the neurophysiologically computational model faithfully reflects the neurophysiological process of human speech production. The multi-connection of neurons is well verified through the "One-to-many" projection between the SOMs. The distribution of tongue and jaw in the well learned motor control map is comparable with which observed in the electrocortigraphic(ECo G) studies.

关键词： neurophysiologically computational model speech production physiological articulatory model self-organizing map

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DFT Studies on the Complexation of Neptunyl by Acetate

Runoff-and erosion-reducing effects of vegetation on the loess hillslopes of China under concentrated flow

第九届全国核化学与放射化学学术研讨会

作者： Jing Su Sven Krger Notker Rsch Jun li Department of Chemistry and Key Laboratory of Organic Optoelectronics and Molecular Engineering of Ministry of Education Tsinghua University Institut fr Physikalische und Theoretische Chemie Technische Universitt Mnchen

Understanding the thermodynamics and kinetics of complexation of actinide cations with various ligands are very important for spent fuel processing and nuclear waste *** a relativistic density functional approach,we have studied the kinetics of complexation of solvated neptunyl(V) ion[NpO(HO)] by acetate. The geometries,thermochemistry and reaction path of the complexation reactions are also *** find two local minima both with five-coordination:a neptunyl

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International Soil and Water Conservation Research 2022年第4期10卷 662-676页

作者： Wenzhao Guo li Luo Hongwei li Wenlong Wang Yun Bai State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau Institute of Water and Soil ConservationNorthwest A&F UniversityYangling712100ShaanxiChina School of Water Conservancy and Architectural Engineering Northwest A&F UniversityYangling712100ShaanxiChina Hanjiang-to-Weihe River Valley Water Diversion Project Construction Co.Ltd. Xian710000ShaanxiChina Yulin University Yulin719000ShaanxiChina

Evaluating the effects of revegetation on runoff and erosion reduction is essential for studying soil and water conservation on the Loess Plateau after implementation of China's Grain for Green ***,quantifying the influence of revegetation on the erosion caused by concentrated runoff in extreme rainstorms is still *** evaluate this influence,scouring-erosion experiments were implemented in situ on the vegetated hillslope plots(GR)and bare hillslope plots(CK).The runoffreducing effects of grass(GRR)averaged 31%,20%and 8%,and the erosion-reducing effects of grass(ger)averaged 93%,95%and 93%on the 5-plots,10-plots and 18-plots,*** ratios of GRR to ger were 0.09e0.33,implying that the ability of vegetation to reduce erosion was greater than its ability to reduce *** GRR and ger obviously decreased as the inflow rate increased,and the GRR decreased as the hillslope gradient increased,but there were no obvious differences in the ger between hillslope *** could decrease the ability of the concentrated flow to carry and transport sediment and increase the energy consumption of the concentrated flow in response to hydraulic *** also significantly reduced the degree of rill *** degree of rill dissection on the GR(0.054e0.087 m^(2)m^(2))was lower than that on the CK(0.061e0.184 m^(2)m^(2)).Our findings provide an essential reference for ecological environment and vegetation restoration on loess hillslopes.

关键词： Soil erosion Concentrated runoff China's grain for green project Vegetation Hydraulic parameters Chinese loess plateau

Nucleophilic amino acids as a renewable alternative to petrochemically-derived amines in glycerol epoxy resins

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Journal of Bioresources and Bioproducts 2024年第2期9卷 222-232页

作者： Yunyi liang Yonghong Luo Yingji Wu Xiaona li Quyet Van Le Jianzhang li Changlei Xia Jiangsu Co-Innovation Center of Efficient Processing and Utilization of Forest Resources International Innovation Center for Forest Chemicals and MaterialsCollege of Materials Science and EngineeringNanjing Forestry UniversityNanjing 210037China Department of Materials Science and Engineering Institute of Green Manufacturing TechnologyKorea UniversitySeoul 02841South Korea

The standard epoxy resin curing agents revealed are from unsustainable petroleum-based sources,which produce poisonous exhaust when *** acids,a bio-based epoxy curing agent with amino and carboxyl groups,are another potential curing ***-soluble epoxy resins cured with lysine(Lys),glutamic acid(Glu),leucine(Leu),and serine(Ser)as amino acids were *** results showed that the water-soluble epoxy resin(glycerol epoxy resins,ger)was cured with Lys and Glu after *** transform infrared(FT-IR)spectroscopic analysis of the ger-Lys showed that the amino and carboxyl groups of Lys primarily reacted with the epoxy groups of *** elongation at break of Lys-cured ger(ger-Lys)cured at 70℃ with a molar ratio of 1꞉0.75 was 75.32%.The fact that elongations at break of ger-Lys(79.43%)were higher than those of ger-Glu(17.33%),respectively supports the decrease of crosslinking density by the amino acid-cured ger *** potential of Lys and Glu alternatives for petrochemical amines is demonstrated and provides promising opportunities for industrial application.

关键词： Curing agent Amino acids Bio-based epoxy resins Lysine Glutamic acid

The Disc Theorem for the Schur Complement of Two Class Submatrices with γ-Diagonally Dominant Properties

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Numerical Mathematics(Theory,Methods and Applications) 2017年第1期10卷 84-97页

作者： Guangqi li Jianzhou liu Juan Zhang Department of Mathematics and Computational Science Xiangtan UniversityXiangtanHunan 411105China College of Science National University of Defense TechnologyChangshaHunan 410073China

The distribution for eigenvalues of Schur complement of matrices plays an important role in many mathematical *** this paper,we firstly present some criteria for *** as application,for two class matrices whose sub-matrices areγ-diagonally dominant and productγ-diagonally dominant,we show that the eigenvalues of the Schur complement are located in the gersgorin discs and the Ostrowski discs of the original matrices under certain conditions.

关键词： Schur complement gersgorin Theorem Ostrowski Theorem H-matrix