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Acta Mechanica Sinica 2016年第2期32卷 244-251页

作者： Kun Xu Guo-Qing Xu chun-Hua zheng Shenzhen Institutes of Advanced Technology Chinese Academy of Sciencesand The Chinese University of Hong Kong Shenzhen College of Advanced Technology University of Chinese Academy of Sciences School of Electronics and Information Tongji University

The wheel-rail adhesion control for regenerative braking systems of high speed electric multiple unit trains is crucial to maintaining the stability,improving the adhesion utilization,and achieving deep energy *** remain technical challenges mainly because of the nonlinear,uncertain,and varying features of wheel-rail contact *** research analyzes the torque transmitting behavior during regenerative braking,and proposes a novel methodology to detect the wheel-rail adhesion ***,applications to the wheel slip prevention during braking are investigated,and the optimal slip ratio control scheme is proposed,which is based on a novel optimal reference generation of the slip ratio and a robust sliding mode *** proposed methodology achieves the optimal braking *** simulation results for uncertain slippery rails verify the effectiveness of the proposed methodology.

关键词： High speed electric multiple unit(EMU) train Regenerative braking Wheel-rail adhesion Optimal slip ratio

Immunobiology of COVID-19: Mechanistic and therapeutic insights from animal models

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Zoological Research 2024年第4期45卷 747-766页

作者： Hong-Yi zheng Tian-Zhang Song yong-Tang zheng State Key Laboratory of Genetic Evolution&Animal Models KIZ-CUHK Joint Laboratory of Bioresources and Molecular Research in Common DiseasesCenter for Biosafety Mega-ScienceKunming Institute of ZoologyChinese Academy of SciencesKunmingYunnan 650223China National Resource Center for Non-Human Primates National Research Facility for Phenotypic&Genetic Analysis of Model Animals(Primate Facility)Kunming Institute of ZoologyChinese Academy of SciencesKunmingYunnan 650107China

The distribution of the immune system throughout the body complicates in vitro assessments of coronavirus disease 2019(COVID-19)immunobiology,often resulting in a lack of reproducibility when extrapolated to the whole ***,developing animal models is imperative for a comprehensive understanding of the pathology and immunology of severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)*** review summarizes current progress related to COVID-19 animal models,including non-human primates(NHPs),mice,and hamsters,with a focus on their roles in exploring the mechanisms of immunopathology,immune protection,and long-term effects of SARS-CoV-2 infection,as well as their application in immunoprevention and immunotherapy of SARS-CoV-2 *** among these animal models and their specific applications are also highlighted,as no single model can fully encapsulate all aspects of *** effectively address the challenges posed by COVID-19,it is essential to select appropriate animal models that can accurately replicate both fatal and non-fatal infections with varying courses and *** animal model libraries and associated research tools is key to resolving the global COVID-19 pandemic,serving as a robust resource for future emerging infectious diseases.

关键词： SARS-CoV-2 COVID-19 Animal models Infection immunology Immunotherapy

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智能精密播种机的优化设计

农机化研究 2025年第1期47卷 114-119页

作者：吴政内蒙古机电职业技术学院呼和浩特010070

智能精密播种机是一种自动化的农业设备,可大幅提高种植效率、减少种植成本。但是,目前智能精密播种机依赖高精度的传感器、控制系统和算法来实现准确的种子投放和深度控制,需要较高的技术要求和技术支持,且对于一些不规则形状的种子或... 详细信息

智能精密播种机是一种自动化的农业设备,可大幅提高种植效率、减少种植成本。但是,目前智能精密播种机依赖高精度的传感器、控制系统和算法来实现准确的种子投放和深度控制,需要较高的技术要求和技术支持,且对于一些不规则形状的种子或大粒小种的种子,适应性较差。为此,提出了一种智能精密播种机优化方案,并使用高精度传感器和控制系统实现多功能播种,控制种子的投放量和调整播种深度,使用节能设备模块化设计和使用易于更换的部件、数据分析功能和简单易用的用户界面。最后,通过田间试验进行功能性试验,结果表明:经过优化后的智能精密播种机播种变异系数≤5%,满足播种农艺要求,可以实现准确的种子投放和深度控制,避免种植密度不均匀和深度不一致等问题,从而提高种植效率和作物品质。

关键词：智能精密播种机优化设计精度多功能性种植效率

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Kinetics and numerical simulation of self-propagating high-temperature synthesis in Ti–Cr–Al–C systems

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Rare Metals 2014年第5期33卷 527-533页

作者： Guo-Bing Ying Xiao-Dong He Shan-Yi Du yong-Ting zheng chun-Cheng Zhu Yu-Ping Wu Cheng Wang Institute of Metals and Protection College of Mechanics and Materials Hohai University Center for Composite Materials and Structure Harbin Institute of Technology College of Chemistry and Chemical Engineering Harbin Normal University

In this paper, Ti–Cr–Al–C materials were investigated by self-propagating high-temperature synthesis（SHS） according to the experimental study and numerical simulation results. The highest adiabatic combustion temperature Tadof 2,467.45 K indicates that the2Ti–0Cr–Al–C is the highest exothermic reaction system in the Ti–Cr–Al–C system. The adiabatic combustion temperature decreases with the increase of the Cr content. And a higher exothermal reaction would result in higher porosity which is induced by the high temperature and pressure of C reducing atmosphere and Al vapor. Combustion characterization of the products shows that the geometrical alternating layers result in the high exothermal reaction and flame-front propagating velocity. The higher the Tadis, the thinner the layer is. To demonstrate the process of the microscopic characterization and show the detailed combustion process closed to the experimental observations, the flame-front propagating velocity and temperature distribution were simulated numerically.

关键词： Self-propagating high-temperature synthesis Temperature distribution Flame-front propagating velocity Numerical simulation

Application of an immune algorithm to settlement prediction

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2009年第1期10卷 93-100页

作者： Jia GUO Jun-jie zheng yong LIU Institute of Geotechnieal and Underground Engineering Huazhong University of Science and Technology Wuhan 430074 China

The settlement curve of the foundation endured the ramp load is an S-type curve,which is usually simulated via Poisson *** at the difficulty of preferences in Poisson curve,an immune algorithm (IA) is *** is able to obtain a multiple quasi-optimum solution while maintaining the population *** this paper,IA is used in an attempt to obtain accurate settlement *** predicted settlements obtained by IA are compared with those predicted by the least squares fitting method (LSM),the Asaoka method and the genetic algorithm (GA).The results show that IA is a useful technique for predicting the settlement of foundations with an acceptable degree of accuracy and has much better performance than GA and the Asaoka methods.

关键词： Settlement Prediction Foundation Immune algorithm (IA)

黄土高原森林林下植被物种多样性及其影响因素

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东北林业大学学报 2025年第2期53卷 66-74页

作者：宫正黄河文明与可持续发展研究中心(河南大学) 开封475001

以黄土高原不同密度刺槐(Robinia pseudoacacia)林为研究对象,通过调查样地的地形及土壤理化性质,利用方差分析、线性拟合、冗余分析等方法,分析林下植被物种多样性特征,探究影响林下植被物种多样性的因素。结果表明:不同林分密度的刺... 详细信息

以黄土高原不同密度刺槐(Robinia pseudoacacia)林为研究对象,通过调查样地的地形及土壤理化性质,利用方差分析、线性拟合、冗余分析等方法,分析林下植被物种多样性特征,探究影响林下植被物种多样性的因素。结果表明:不同林分密度的刺槐林林下植被物种多样性存在显著差异(P<0.05)。刺槐林下灌木Margalef丰富度指数随坡向的增大而减小,林下草本植物Margalef丰富度指数随坡度的增加而减小。刺槐林下灌木植物物种多样性的主要影响因素是密度、坡向、土壤全氮质量分数、土壤铵态氮质量分数,草本植物物种多样性的主要影响因素是土壤速效磷质量分数。

关键词：刺槐林物种多样性影响因素冗余分析黄土高原

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小麦籽粒胚乳发育及其与营养品质的关系

麦类作物学报 2025年第1期45卷 96-102页

作者：郑彦坤安庆师范大学生命科学学院安徽安庆246133

小麦是人类的主要粮食作物之一,其籽粒是绿色有机食品与营养保健食品的重要原料。小麦籽粒中胚乳组织可分为胚乳运输细胞与贮藏细胞,前者是养分进入胚乳与胚的关键通道,后者是籽粒营养物质积累的主体,二者的发育状况都与籽粒的营养品质... 详细信息

小麦是人类的主要粮食作物之一,其籽粒是绿色有机食品与营养保健食品的重要原料。小麦籽粒中胚乳组织可分为胚乳运输细胞与贮藏细胞,前者是养分进入胚乳与胚的关键通道,后者是籽粒营养物质积累的主体,二者的发育状况都与籽粒的营养品质密切相关。本文综述了胚乳运输细胞与贮藏细胞的发育规律及其作用机制,总结了小麦籽粒胚乳发育及其与营养品质的关系,为高产优质小麦品种的培育提供理论依据。

关键词：小麦胚乳发育营养品质

Gut-brain axis as a bridge in obesity and depression:Mechanistic exploration and therapeutic prospects

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World Journal of Psychiatry 2025年第1期15卷 12-20页

作者： Rui-Ying Fang Xiao-Rui Pan Xin-Xing Zeng zheng-zheng Li Bo-Fan Chen Hai-Min Zeng Jie Peng The Second Clinical Medical College The Second Affiliated HospitalJiangxi Medical CollegeNanchang UniversityNanchang 330006Jiangxi ProvinceChina

A recent study by Wang et al,published in the World Journal of Psychiatry,provided preventative and therapeutic strategies for the comorbidity of obesity and *** gut-brain axis,which acts as a two-way communication system between the gastrointestinal tract and the central nervous system,plays a pivotal role in the pathogenesis of these *** suggests that metabolic byproducts,such as short-chain fatty acids,lipopolysaccharide and bile acids,which are generated by the gut microbiota,along with neurotransmitters and inflammatory mediators within the gut-brain axis,modulate the host's metabolic processes,neuronal regulation,and immune responses through diverse *** interaction between obesity and depression via the gut-brain axis involves disruptions in the gut microbiota balance,inflammatory immune responses,and alterations in the neuroendocrine *** the gut-brain axis,for example,through a ketogenic diet,the use of probiotics,and the supplementation of antioxidants,offers new remedial approaches for obesity and *** research that explores the mechanisms of the gut-brain axis is needed to provide more evidence for clinical treatment.

关键词： Gut-brain axis Obesity Depression Gut microbiota Mechanism

Formation of M_(n+1)AX_n phases in Ti–Cr–Al–C systems by self-propagating high-temperature synthesis

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Rare Metals 2014年第4期33卷 419-426页

作者： Guo-Bing Ying Xiao-Dong He Shan-Yi Du chun-Cheng Zhu yong-Ting zheng Yu-Ping Wu Cheng Wang Institute of Metals and Protection College of Mechanics and MaterialsHohai University Center for Composite Materials and Structure Harbin Institute of Technology College of Chemistry and Chemical Engineering Harbin Normal University

In this paper, phase composition of the Mn＋l- AXn phases by self-propagating high-temperature synthesis （SHS） was determined using Ti, Cr, A1, and carbon black as raw materials. And, phase composition and micro- structures of the Mn＋1AXn phases-contained bulk by SHS with the pseudo-hot isostatic pressing （SHS/PHIP） were investigated in Ti-Cr-AI-C systems raw materials. Riet- veld XRD refinement was introduced to study the lattice parameters and phase composition of the resultant phases from the SHSed and SHS/PHIPed samples. Ti2A1Cx, Ti3A1C2, and Cr2A1Cx by SHS were detected in the Ti-Cr- A1-C systems, as well as the binary carbide of TiC and intermetallics. The mechanical properties of the synthe- sized bulk samples were determined, exhibiting a high strength and toughness compared with the typical mono- lithic Mn＋1AXn phase ceramics. It is indicated that the samples prepared by SHS/PHIP are identified to be a strategy for improving the mechanical properties of monolithic Mn＋1AXn phase.

关键词： SHS/PHIP Mn+lAXn phases Phasecomposition Microstructure Mechanical properties

Comparison of different techniques for time-frequency analysis of internal combustion engine vibration signals

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2011年第7期12卷 519-531页

作者： Yang JIN Zhi-yong HAO Xu zheng Department of Energy Engineering Zhejiang University Hangzhou 310027 China Department of Automotive Engineering Hubei University of Automotive Technology Shiyan 442002 China

In this study,we report an analysis of cylinder head vibration signals at a steady engine speed using short-time Fourier transform(STFT).Three popular time-frequency analysis techniques,i.e.,STFT,analytic wavelet transform(AWT) and S transform(ST),have been *** and ST are often applied in engine signal *** particular,an AWT expression in terms of the quality factor Q and an analytical relationship between ST and AWT have been *** time-frequency resolution of a Gaussian function windowed STFT was studied via numerical *** on the simulation,the empirical limits for the lowest distinguishable frequency as well as the time and frequency resolutions were *** can provide insights for window width selection,spectrogram interpretation and artifact *** function windowed STFTs were applied to some cylinder head vibration *** spectrograms of the same signals from ST and AWT were also determined for *** results indicate that the uniform resolution feature of STFT is not necessarily a disadvantage for time-frequency analysis of vibration signals when the engine is in stationary state because it can more accurately localize the frequency components excited by transient excitations without much loss of time resolution.

关键词： Short-time Fourier transform(STFT) Gaussian window Time-frequency resolution limits Internal combustion(IC) engine Vibration signals Analytic wavelet transform(AWT) S transform(ST)