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Vibration Control of the Rail Grinding Vehicle with Abrasive Belt Based on Structural Optimization and Lightweight Design

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Chinese Journal of Mechanical Engineering 2024年第3期37卷 311-337页

作者： Wengang Fan Shuai Zhang Zhiwei Wu Yi Liu jiangnan Yu school of Mechanical Electronic and Control EngineeringBeijing Jiaotong UniversityBeijing 100044China Key Laboratory of Vehicle Advanced Manufacturing Measuring and Control TechnologyMinistry of EducationBeijing 100044China China Railway Materials Operation and Maintenance Technology Co. LtdBeijing 100036China

As a new grinding and maintenance technology,rail belt grinding shows significant advantages in many applications The dynamic characteristics of the rail belt grinding vehicle largely determines its grinding performance and service *** order to explore the vibration control method of the rail grinding vehicle with abrasive belt,the vibration response changes in structural optimization and lightweight design are respectively analyzed through transient response and random vibration simulations in this ***,the transient response simulation analysis of the rail grinding vehicle with abrasive belt is carried out under operating conditions and non-operating ***,the vibration control of the grinding vehicle is implemented by setting vibration isolation elements,optimizing the structure,and increasing ***,in order to further explore the dynamic characteristics of the rail grinding vehicle,the random vibration simulation analysis of the grinding vehicle is carried out under the condition of the horizontal irregularity of the American AAR6 ***,by replacing the Q2.5 steel frame material with 7075 aluminum alloy and LA43M magnesium alloy,both vibration control and lightweight design can be achieved *** results of transient dynamic response analysis show that the acceleration of most positions in the two working conditions exceeds the standard value in GB/T 1742.-1998 *** optimizing the structure of the grinding vehicle in three ways,the average vibration acceleration of the whole car is reduced by about 55.1%from 15.6 m/s^(2. to 7.0 m/s^(2..The results of random vibration analysis show that the grinding vehicle with Q2.5 steel frame does not meet the safety conditions of 3σ.By changing frame material,the maximum vibration stress of the vehicle can be reduced from 2.0.7 MPa to 160.0 MPa and the weight of the grinding vehicle is reduced by about 2..7%from 1500 kg to 1175 *** modal analysis results indic

关键词： Vibration control Dynamic characteristics Structural optimization Lightweight design Modal analysis

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Multi-class classification of pathological myopia based on fundus photography

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Journal of Innovative Optical Health sciences 2024年第6期17卷 125-136页

作者： Jiaqing Zhao Guogang Cao jiangnan He Cuixia Dai Shanghai Institute of Technology No.100 Haiquan RoadFengxian DistrictShanghaiP.R.China Shanghai Eye Diseases Prevention&Treatment Center Shanghai Eye HospitalSchool of MedicineTongji UniversityShanghai 200331P.R.China

Pathological myopia(PM)is a severe ocular disease leading to *** a traditional noninvasive diagnostic method,fundus color photography(FCP)is widely used in detecting PM due to its highfidelity and ***,manual examination of fundus photographs for PM is time-consuming and prone to high error *** automated detection technologies have yet to study the detailed classification in diagnosing different stages of PM *** this paper,we proposed an intelligent system which utilized Resnet101 technology to multi-categorically diagnose PM by classifying FCPs with different stages of *** system subdivided different stages of PM into eight subcategories,aiming to enhance the precision and e±ciency of the diagnostic *** achieved an average accuracy rate of 98.86%in detection of PM,with an area under the curve(AUC)of 98.96%.For the eight subcategories of PM,the detection accuracy reached 99.63%,with an AUC of 99.98%.Compared with other widely used multi-class models such as VGG16,Vision Transformer(VIT),E±cientNet,this system demonstrates higher accuracy and *** artificial intelligence system is designed to be easily integrated into existing clinical diagnostic tools,providing an e±cient solution for large-scale PM screening.

关键词： Fundus color photography pathological myopia deep learning Resnet101.

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Improved Weighted Local Contrast Method for Infrared Small Target Detection

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Journal of Beijing Institute of Technology 2024年第1期33卷 19-27页

作者： Pengge Ma jiangnan Wang Dongdong Pang Tao Shan Junling Sun Qiuchun Jin school of Intelligent Engineering Zhengzhou University of AeronauticsZhengzhou 450000China Beijing Key Laboratory of Fractional Signals and Systems School of Information and ElectronicsBeijing Institute of TechnologyBeijing 100081China

In order to address the problem of high false alarm rate and low probabilities of infrared small target detection in complex low-altitude background,an infrared small target detection method based on improved weighted local contrast is proposed in this ***,the ratio information between the target and local background is utilized as an enhancement *** local contrast is calculated by incorporating the heterogeneity between the target and local ***,a local product weighted method is designed based on the spatial dissimilarity between target and background to further enhance target while suppressing ***,the location of target is obtained by adaptive threshold *** experimental results demonstrate,the method shows superior performance in several evaluation metrics compared with six existing algorithms on different datasets containing targets such as unmanned aerial vehicles(UAV).

关键词： infrared small target unmanned aerial vehicles(UAV) local contrast target detection

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Two H3K36 methyltransferases differentially associate with transcriptional activity and enrichment of facultative heterochromatin in rice blast fungus

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aBIOTECH 2024年第1期5卷 1-16页

作者： Mengting Xu Ziyue Sun Huanbin Shi jiangnan Yue Xiaohui Xiong Zhongling Wu Yanjun Kou Zeng Tao Ministry of Agriculture Key Laboratory of Molecular Biology of Crop Pathogens and Insects Institute of BiotechnologyZhejiang UniversityHangzhou 310058China State Key Lab of Rice Biology and Breeding China National Rice Research InstituteHangzhou 310021China

Di-and tri-methylation of lysine 36 on histone H3(H3K36me2.3)is catalysed by histone methyltransferase Set2.which plays an essential role in transcriptional *** there is a single H3K36 methyltransferase in yeast and higher eukaryotes,two H3K36 methyltransferases,Ash1 and Set2.were present in many filamentous ***,their roles in H3K36 methylation and transcriptional regulation remained *** with methods of RNA-seq and ChIP-seq,we revealed that both Ash1 and Set2.are redundantly required for the full H3K36me2.3 activity in Magnaporthe oryzae,which causes the devastating worldwide rice blast ***1 and Set2.distinguish genomic H3K36me2.3-marked regions and are differentially associated with repressed and activated transcription,***,Ash1-catalysed H3K36me2.was co-localized with H3K2.me3 at the chromatin,and Ash1 was required for the enrichment and transcriptional silencing of H3K2.me3-occupied *** the different roles of Ash1 and Set2.in H3K36me2.3 enrichment and transcriptional regulation on the stress-responsive genes,they differentially respond to various stresses in ***,we reveal a novel mechanism by which two H3K36 methyltransferases catalyze H3K36me2.3 that differentially associate with transcriptional activities and contribute to enrichment of facultative heterochromatin in eukaryotes.

关键词： Ash1 Facultative heterochromatin H3K36me2.3 Magnaporthe oryzae Set2 Transcriptional regulation

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Catalytic anode surface enabling in situ polymerization of gel polymer electrolyte for stable Li metal batteries

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Nano Research 2024年第6期17卷 5216-5223页

作者： Guocheng Li Kang Liang Yuanjian Li Xiangrui Duan Lin Fu Zhao Cai Zhaofu Zhang jiangnan Dai Yongming Sun Wuhan National Laboratory for Optoelectronics Huazhong University of Science and TechnologyWuhan 430074China The Institute of Technological sciences Wuhan UniversityWuhan 430074China Faculty of Materials science and Chemistry China University of Geoscience(Wuhan)Wuhan 430074China

Employing quasi-solid-state gel polymer electrolyte(GPE)instead of the liquid counterpart has been regarded as a promising strategy for improving the electrochemical performance of Li metal ***,the poor and uneven interfacial contact between Li metal anode and GPE could cause large interfacial resistance and electrochemical Li stripping/plating inhomogeneity,deteriorating the electrochemical ***,we proposed that the functional component of composite anode could work as the catalyst to promote the in situ polymerization reaction,and we experimentally realized the integration of polymerized-dioxolane electrolyte and Li/Li_(2.)Sn_(5)/LiF composite electrode with low interfacial resistance and good stability by in situ catalyzation ***,the reaction kinetics and stability of metallic Li anode were significantly *** a demonstration,symmetric cell using such a GPE-Li/Li_(2.)Sn_(5)/LiF integration achieved stable cycling beyond 2.0 cycles with small potential hysteresis of 2. mV at 1 mA·cm^(−2.and 1 mAh·cm^(−2.,far outperforming the counterpart regular GPE on pure *** with LiNi0.5Co0.3Mn0.2.2.the full cell with the GPE-Li/Li_(2.)Sn_(5)/LiF integration maintained 85.7%of the original capacity after 100 cycles at 0.5 C(1 C=2.0 mA·g^(−1)).Our research provides a promising strategy for reducing the resistance between GPE and Li metal anode,and realizes Li metal batteries with enhance electrochemical performance.

关键词： catalyzation polymerization interface resistance interfacial stability Li metal batteries electrochemical performance

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Photonic crystal-connected bidirectional micro-ring resonator array for duplex mode and wavelength channel(de)multiplexing

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Photonics Research 2024年第8期12卷 1802-1812页

作者： ZHIWEI GUAN CHAOFENG WANG CHUANGXIN XIE HAISHENG WU JUNMIN LIU HUAPENG YE DIANYUAN FAN jiangnan XIAO SHUQING CHEN International Collaborative Laboratory of 2. Materials for Optoelectronics science and Technology Institute of Microscale OptoelectronicsShenzhen UniversityShenzhen 518060China College of Physics and Engineering Technology Minzu Normal University of XingyiXingyi 562400China College of New Materials and New Energies Shenzhen Technology UniversityShenzhen 518118China Guangdong Provincial Key Laboratory of Optical Information Materials and Technology and Institute of Electronic Paper Displays South China Academy of Advanced OptoelectronicsSouth China Normal UniversityGuangzhou 510006China Terahertz Technology Innovation Research Institute Shanghai Key Laboratory of Modern Optical SystemTerahertz Science Cooperative Innovation CenterSchool of Optical-Electrical Computer EngineeringUniversity of Shanghai for Science and TechnologyShanghai 200093China

The progress of on-chip optical communication relies on integrated multi-dimensional mode(de)multiplexers to enhance communication capacity and establish comprehensive ***,existing multi-dimensional(de)multiplexers,involving modes and wavelengths,face limitations due to their reliance on single-directional total internal reflection and multi-level mode conversion based on directional coupling *** constraints restrict their potential for full-duplex functionality and highly integrated *** solve these problems by introducing a photonic-like crystal-connected bidirectional micro-ring resonator array(PBMRA)and apply it to duplex mode-wavelength multiplexing *** directional independence of total internal reflection and the cumulative effect of the subwavelength-scale pillar within the single-level photonic crystal enable bidirectional mode and wavelength multiplexed signals to transmit among multi-pair nodes without interference,improving on-chip integration in single-level mode *** a proof of concept,we fabricated a nine-channel bidirectional multi-dimensional(de)multiplexer,featuring three wavelengths and three TE modes,compactly housed within a footprint of 80μm×80μm,which efficiently transmits QPSK-OFDM signals at a rate of 2.6 Gbit/s,achieving a bit error rate lower than 10^(-4).Leveraging the co-ring transmission characteristic and the orthogonality of the mode-wavelength channel,this(de)multiplexer also enables a doubling of communication capacity using two physical transmission channels.

关键词： resonator channel mode

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Orientation-Singularity Representation and Orientation-Capability Computation of a Special Class of the Gough-Stewart Parallel Mechanisms Using Unit Quaternion

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Chinese Journal of Mechanical Engineering 2012年第6期25卷 1096-1104页

作者： LI Baokun1, 2. CAO Yi1, 3, *, ZHANG Qiuju1, and HUANG Zhen4 1 school of Mechanical Engineering, jiangnan university, {2., China 2.school of Mechanical Engineering, Anhui university of science and Technology, Huainan 2.2.01, China 3 State Key Laboratory of Fluid Power Transmission and Control, Hangzhou 31002., China 4 Robotics Research Center, Yanshan university, Qinhuangdao 066004, China 1. school of Mechanical Engineering Jiangnan University Wuxi 214122 China 2. school of Mechanical Engineering Anhui University of Science and Technology Huainan 232001 China 3. State Key Laboratory of Fluid Power Transmission and Control Hangzhou 310027 China 4. Robotics Research Center Yanshan University Qinhuangdao 066004 China

Singular configuration seriously affects the performance of the Gough-Stewart parallel mechanism and has attracted many researchers’ attentions. However, most of existing topics often focus on the position-singularity of the mechanism for a constant-orientation, but few reports research the orientation-singularity for a given position. In order to investigate the orientation-singularity of the Gough-Stewart parallel mechanisms with two dissimilar semi-regular hexagonal platforms for a given position, after constructing the discrimination matrix of the singular configuration of the mechanism and computing the determinant of this matrix by using unit quaternion as the orientation parameters which can avoid the singularities in parameterization, a general symbolic expression representing the three-dimensional orientation-singularity locus for a given position is obtained and the three-dimensional view of the orientation-singularity locus is further described. The orientation-singularity-free void exists inside the orientation-singularity locus, but the shape of the orientation-singularity-free void is irregular and inconvenient for the design of the mechanism. The minimal inscribed sphere of the three-dimensional orientation-singularity locus namely the orientation-singularity-free ball is described. The radius of the ball orientation-capability is used as the measurement for the orientation-singularity-free void size. A new efficient algorithm is proposed for the computation of the orientation-capability. Finally, the influences of the geometry parameters and the different positions of the mechanism on the orientation-capability are discussed. A new method of the singularity analysis of the Gough-Stewart parallel mechanism is advanced based on the unit quaternion, and the research finds have important referential value for the configuration parameters optimization of this class of the parallel mechanisms with the goal of having the maximal singularity-free zone.

关键词： parallel mechanism unit quaternion orientation-singularity orientation-singularity-free void orientation-capability

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Interfacial Microstructure and Properties of Ti(C, N)/Ni Bonded by Transient Liquid-phase Diffusion

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Journal of Wuhan university of Technology(Materials science) 2009年第3期24卷 432-439页

作者：周世权熊惟皓 school of Mechanical science and Engineering Huazhong University of Science and Technology Department of Mechanical Engineering University of Waterloo school of Materials science and Engineering Huazhong University of Science and Technology

Effects of the main process parameters（temperature and time） on microstructure and properties of Ti（C, N）/Ni interface bonded by （Cu＋Nb） interlayer in a vacuum diffusion bonding device were investigated. The interfacial microstructures consisted initially of Ni3Nb metallic compound and eutectic of Ni3Nb ＋ CuNiss, and finally transformed to （Ti, Nb）（C, N）＋Ni3Nb near Ti （C, N） and NiCuss ＋ Ni3Nb near Ni when diffusion bonding temperature was 1 52.-1 573 K. It was clear that Cu was a constituent in the transient liquid phase （TLP） into which Ni was dissolved by forming Cu-Ni transition liquid. Nb was dissolved in Cu-Ni transition liquid rapidly. Ti （C, N） conld be wetted by resultant Ni-Nb-Cu transient liquid phase which was followed by a little （Ti, Nb）（C, N） solid solution formed at interface. This increased the interface combining capability. Ultimately the interface shear strength was able to reach 140 MPa. The theoretle analysis and experimental results show that the growth of interfacial reaction layer Ni3Nb accords with parabola law, and the activation energy of diffusion reaction is 115.0±0.5 kJ/mol, while the diffusion reaction speed constant is 12.53 mm/s^1/2.

关键词： vacuum diffusion bonding transient liquid phase (TLP) diffusion bonding interlayer activation energy

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Development and Application of High Performance X80 Line Pipe for the 2.(nd) West-East Gas Pipeline

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Journal of Iron and Steel Research International 2011年第S1期18卷 39-48页

作者： LI He-lin 1 , HUO Chun-yong 1 , JI Ling-kang 1, 2., LI Yang 1, 3 (1. CNPC Tubular Goods Research Institute, Xi’an 710065, China 2. . school of Material science and Engineering, Xi’an Jiaotong {2., Xi’an 710049, China 3. school of Material science and Engineering, {2. of science and Technology Beijing, Beijing 100083, China) CNPC Tubular Goods Res Inst Xian 710065 Peoples R China Xi An Jiao Tong Univ Sch Mat Sci & Engn Xian 710049 Peoples R China Univ Sci & Technol Beijing Sch Mat Sci & Engn Beijing 100083 Peoples R China

It is the development tendency of gas pipeline to improve strength of line pipe and transmission pressure, which is an important symbol of the progress of gas pipeline technology. The 2.d West-East Gas Pipeline (the 2.nd WEGP) is the largest-scale X80 high pressure gas pipeline project in the world. Through the joint development project by Pipeline Company, research institute, and steel company, a series of achievements of technology have been obtained, which makes it possible to apply pressure of 12.MPa and X80 LSAW and HSAW pipe for the 2.nd WEGP. Specifications of X80 steel and pipe have been issued based on API 5L. High performance X80 steel and pipe have been developed and meets the Specification. General design conception of applying HSAW pipe and LSAW pipe on gas transmission trunk line with large diameter and high pressure has been established. Failure control of the 2.nd WEGP has been carried out to avoid failure and reduce the lost which based on analysis of pipeline failure mode. In this paper, research and development of high performance X80 welded pipe, establishment of technical route of joint application of HSAW and LSAW steel pipe and key technology of failure control are emphatically discussed.

关键词： 2.nd WEGP acicular ferrite failure control arrest toughness strain-based design

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Effects of maternal methyl donor intake during pregnancy on ileum methylation and function in an intrauterine growth restriction pig model

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Journal of Animal science and Biotechnology 2024年第3期15卷 1173-1189页

作者： Yan Lin jiangnan Wu Yong Zhuo Bin Feng Zhengfeng Fang Shengyu Xu Jian Li Hua Zhao De Wu Lun Hua Lianqiang Che Key Laboratory of Animal Disease‑Resistance Nutrition Animal Nutrition InstituteSichuan Agricultural UniversityChengdu 611130SichuanChina

Background Intrauterine growth retardation(IUGR)affects intestinal growth,morphology,and function,which leads to poor growth performance and high *** present study explored whether maternal dietary methyl donor(MET)supplementation alleviates IUGR and enhances offspring’s growth performance by improving intestinal growth,function,and DNA methylation of the ileum in a porcine IUGR *** Forty multiparous sows were allocated to the control or MET diet groups from mating until *** farrowing,8 pairs of IUGR and normal birth weight piglets from 8 litters were selected for sampling before suckling *** The results showed that maternal MET supplementation tended to decrease the IUGR incidence and increased the average weaning weight of ***,maternal MET supplementation significantly reduced the plasma concentrations of isoleucine,cysteine,urea,and total amino acids in sows and newborn *** also increased lactase and sucrase activity in the jejunum of newborn *** addition resulted in lower ileal methionine synthase activity and increased betaine homocysteine S-methyltransferase activity in the ileum of newborn *** methylation analysis of the ileum showed that MET supplementation increased the methyla-tion level of DNA CpG sites in the ileum of newborn ***-regulated differentially methylated genes were enriched in folic acid binding,insulin receptor signaling pathway,and endothelial cell *** contrast,up-regulated methylated genes were enriched in growth hormone receptor signaling pathway and nitric oxide biosyn-thetic *** Maternal MET supplementation can reduce the incidence of IUGR and increase the weaning litter weight of piglets,which may be associated with better intestinal function and methylation status.

关键词： Ileum Intrauterine growth restriction Methyl donor Methylation Sows

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