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New analytical model of elastic-plastic contact for three-dimensional rough surfaces considering interaction of asperities

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Friction 2022年第2期10卷 217-231页

作者： Yuqin WEN jinyuan TANG Wei ZHOU Lin LI Caichao ZHU State Key L aboratory of High Performance Complex Manufacturing Central South University.Changsha 410083.China Hunan Provincial Key Laboratory of High Efficiency and Precision Machining of Difficult-to-Cut Material Hunan University of Science and TechnologyXiangtan 411201China State Key Laboratory of Mechanical Transmission Chongqing UniversityXiangtan 400044China

The contact calculation of three-dimensional real rough surfaces is the frontier field of tribology and surface *** this study,we consider the interaction and elastic-plastic deformation characteristics of asperities and further,propose an analytical contact calculation method for rough surfaces considering the interaction of *** on the watershed algorithm,the rough surface is segmented and the asperities are reconstructed into *** to the height relationship between the asperities,the definition of the deformation reference height of the matrix between each couple of asperities is ***,the calculation formula of the substrate deformation is provided according to the local contact pressure considering the elastic-plastic deformation of the asperity,and the contact state under a specific load is determined using the iterative correction *** results correspond with those of finite element numerical calculation and the study reveals the following:(1)compared with the results obtained without considering the asperity interaction,contact area,distance,and stiffness will be reduced by 6.6%,19.6%,and 49.5%,respectively,when the influence of asperity interaction is considered;(2)the interaction of the asperities has the greatest influence on the surface contact distance and *** the same load,the existence of asperity interaction will reduce the contact distance,area,and stiffness;(3)considering the interaction of the asperities,the higher asperity will bear more load,but it will simultaneously reduce the contact of the surrounding area and increase that of the distant *** calculation method proposed in this study has the advantages of high calculation efficiency and accuracy,thus,providing the calculation basis and method for subsequent studies on service performance of rough surfaces,such as the calculation of contact stiffness and fatigue performance analysis of rough surfaces.

关键词： calculation method contact analysis interaction of asperities rough surface

Cross-Lingual Non-Ferrous Metals Related News Recognition Method Based on CNN with A Limited Bi-Lingual Dictionary

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Computers, Materials & Continua 2019年第2期58卷 379-389页

作者： Xudong Hong Xiao Zheng jinyuan Xia Linna Wei Anhui University of Technology Maanshan243002China

To acquire non-ferrous metals related news from different countries’internet,we proposed a cross-lingual non-ferrous metals related news recognition method based on CNN with a limited bilingual ***,considering the lack of related language resources of non-ferrous metals,we use a limited bilingual dictionary and CCA to learn cross-lingual word vector and to represent news in different languages ***,to improve the effect of recognition,we use a variant of the CNN to learn recognition features and construct the recognition *** experimental results show that our proposed method acquires better results.

关键词： Non-ferrous metal CNN cross-lingual text classification word vector

Molecular Characterization of a Cytosolic Malate Dehydrogenase Gene（GhcMDH1） from Cotton

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Chemical Research in Chinese Universities 2017年第1期33卷 87-93页

作者： IMRAN Muhammad ZHANG Bing TANG Kai LIU jinyuan Laboratory of Plant Molecular Biology Center for Plant Biology School of Life Sciences Tsinghua University Beijing 100084 R R. China Institute of Botany Chinese Academy of Sciences Nanjing 210014 P R. China

Malate dehydrogenase（MDH） is a key enzyme that catalyzes the reversible oxidation of oxaloacetate to malate and plays an important role in the physiological processes of plant growth and development. However, cyto- solic malate dehydrogenase（cMDH）, which is crucial for malate synthesis in the cytosol, still has not been extensively characterized in plants. Here, we isolated a cytosolic malate dehydrogenase gene, designated as GhcMDH1, from Gossypium hirsutum and characterized its possible molecular function in cotton fiber. The cloned cDNA of GhcMDH1 is 1520 base pairs in length, and has an open reading frame of 999 base pairs, encoding for 332 amino acid residues with an estimated molecular weight of 35580 and pI of 6.35. Sequence alignment showed that the de- duced amino acid sequence of GhcMDH1 protein shared a high similarity to other plant cMDHs. Confocal and im- munological analysis confirmed that GhcMDH1 protein was subcellularly localized to the cytosol. Quantitative real-time polymerase chain reaction（PCR） revealed that GhcMDH1 was constitutively expressed in all vegetative cotton tissues, with slightly lower levels in roots than stems and leaves. Interestingly, the transcripts of GhcMDH1 were detected in 5--25 d post anthesis（DPA） fibers and highly abundant at 15 DPA fibers. The total MDH activities and malate contents of cotton fibers were positively correlated with the fiber elongation rates, suggesting that GhcMDH1 may function in malate synthesis in fast fiber elongation. In agreement with this suspicion, the recombi- nant His-GhcMDH1 protein mainly drives the reaction towards malate generation in vitro. In conclusion, our mole- cular characterization of the GhcMDH1 gene provides valuable insights to further investigate the malate equilibrium in cotton fiber development.

关键词： Cotton Cytosolic malate dehydrogenase Malate synthesis Fiber development

Accelerating Packet Classification with Counting Bloom Filters for Virtual Open Flow Switching

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China Communications 2018年第10期15卷 117-128页

作者： jinyuan Zhao Zhigang Hu Bing Xiong Keqin Li School of Software Central South University School of Computer and Communication Hunan Institute of Engineering School of Computer and Communication Engineering Changsha University of Science and Technology Department of Computer Science State University of New York at New Paltz

The growing trend of network virtualization results in a widespread adoption of virtual switches in virtualized environments. However, virtual switching is confronted with great performance challenges regarding packet classification especially in Open Flow-based software defined networks. This paper first takes an insight into packet classification in virtual Open Flow switching, and points out that its performance bottleneck is dominated by flow table traversals of multiple failed mask probing for each arrived packet. Then we are motivated to propose an efficient packet classification algorithm based on counting bloom filters. In particular, counting bloom filters are applied to predict the failures of flow table lookups with great possibilities, and bypass flow table traversals for failed mask probing. Finally, our proposed packet classification algorithm is evaluated with real network traffic traces by experiments. The experimental results indicate that our proposed algorithm outperforms the classical one in Open v Switch in terms of average search length, and contributes to promote virtual Open Flow switching performance.

关键词： OpenFlow virtual switching packet classification flow table lookups counting bloom filters

Random walk search in unstructured P2P

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Journal of Systems Engineering and Electronics 2006年第3期17卷 648-653页

作者： Jia Zhaoqing You jinyuan Rao Ruonan Li Minglu Dept. of Computer Science and Engineering Shanghai Jiaotong Univ. Shanghai 200030 P. R. China Dept. of Foundation Science the First Aeronautical Inst. of the Air Force Xinyang 464000 P. R. China

Unstructured P2P has power-law link distribution, and the random walk in power-law networks is analyzed. The analysis results show that the probability that a random walker walks through the high degree nodes is high in the power-law network, and the information on the high degree nodes can be easily found through random walk. Random walk spread and random walk search method （RWSS） is proposed based on the analysis result. Simulation results show that RWSS achieves high success rates at low cost and is robust to high degree node failure.

关键词： unstructured P2P search random walk search random walk spread power-law network.

Survey of lightweighting methods of huge 3D models for online Web3D visualization

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Virtual Reality & Intelligent Hardware 2023年第5期5卷 395-406页

作者： Xiaojun LIU jinyuan JIA Chang LIU Department of mathematics and Information Engineering Nanhu College of Jiaxing UniversityZhejiang 314000China Department of Softwere Engineeging Tongji UniversityShanghai 201804China School of Information Technology Nanchang Hangkong UniversityNanchang 330063China

Background With the rapid development of Web3D technologies, the online Web3D visualization, particularly for complex models or scenes, has been in a great demand. Owing to the major conflict between the Web3D system load and resource consumption in the processing of these huge models, the huge 3D model lightweighting methods for online Web3D visualization are reviewed in this paper. Methods By observing the geometry redundancy introduced by man-made operations in the modeling procedure, several categories of light-weighting related work that aim at reducing the amount of data and resource consumption are elaborated for Web3D visualization. Results By comparing perspectives, the characteristics of each method are summarized, and among the reviewed methods, the geometric redundancy removal that achieves the lightweight goal by detecting and removing the repeated components is an appropriate method for current online Web3D visualization. Meanwhile, the learning algorithm, still in improvement period at present, is our expected future research topic. Conclusions Various aspects should be considered in an efficient lightweight method for online Web3D visualization, such as characteristics of original data, combination or extension of existing methods, scheduling strategy, cache man-agement, and rendering mechanism. Meanwhile, innovation methods, particularly the learning algorithm, are worth exploring.

关键词： Huge 3D model Lightweighting Web3D Visualization Shape descriptor

Tribological behavior of coated spur gear pairs with tooth surface roughness

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Friction 2019年第2期7卷 117-128页

作者： Huaiju LIU Heli LIU Caichao ZHU Peitang WEI jinyuan TANG State Key Laboratory of Mechanical Transmissions Chongqing University State Key Laboratory of High Performance Complex Manufacturing Central South University

Coating is an effective way to reduce friction and wear and to improve the contact-fatigue lives of gear components, which further guarantees a longer service life and better reliability of industrial machinery. The fact that the influence coefficient linking the tractions and stress components could not be expressed explicitly increases the difficulty of coated solids contact analysis. The complicated tribological behavior between tooth surfaces influenced by lubrication and surface roughness further adds difficulty to the coated gear pair contact problems. A numerical elastohydrodynamic lubricated(EHL) contact model of a coated gear pair is proposed by considering the coupled effects of gear kinematics, coating properties, lubrication, and surface roughness. The frequency response function and the discrete convolute, fast Fourier transformation(DC-FFT) method are combined to calculate the surface deformation and the subsurface stress fields at each meshing position along the line of action(LOA). The Ree-Eyring fluid is assumed to incorporate the non-Newtonian effect, which is represented in the generalized Reynolds equation. Influences of the ratio between the Young's modulus of the coating and the substrate on the contact performance, such as pressure, film thickness, tooth friction coefficient, and subsurface stress field, are studied. The effect of the root mean square(RMS) value of the tooth surface roughness is studied by introducing the roughness data, deterministically measured by an optical profiler.

关键词： coating gear elastohydrodynamic lubrication (EHL) surface roughness

Multiplex imaging reveals the architecture of the tumor immune microenvironment

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Cancer Biology & Medicine 2021年第4期18卷 949-954页

作者： Junlei Zhang jinyuan Song Jianpeng Sheng Xueli Bai Tingbo Liang Department of Hepatobiliary and Pancreatic Surgery Zhejiang Provincial Key Laboratory of Pancreatic Diseasethe First Affiliated HospitalZhejiang University School of MedicineZhejiang University Cancer CentreZhejiang UniversityHangzhou 310002China

The tumor immune microenvironment(TME)is composed of a variety of components,such as tumor cells,immune cells,and the extracellular *** TME has been studied through transcriptomic,proteomic,metabolomic,and phosphoprot... 详细信息

关键词： immune tumor microenvironment

Cosmic-ray exposure and gas retention ages of the Guang-mingshan(H5) chondrite

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Chinese Science Bulletin 2001年第18期46卷 1544-1546页

作者： WANG Daode LIN Yangting LIU jinyuan Guangzhou Institute of Geochemistry Chinese Academy of SciencesGuangzhou 510640China Dalian Museum of Natural History Dalian 116023China

Isotopic compositions of noble gases from the Guangmingshan chondrite were analyzed. Based on the analyses of cosmogenic nuclei, cosmic-ray exposure age of the meteorite is (65±10.0) Ma (3He), (80±12) Ma (21Ne) and (65±10.0) Ma (38Ar), with an average of 70 Ma. This is the highest exposure age of H-group ordinary chondrites. Gas retention ages of K-Ar and U, Th-4He are (4230±100) Ma and (3300±60) Ma, respectively. The smaller ages of 3He than 21Ne and 4He than Ar suggest that both 3He and 4He lost together. This is probably related to a solar heating effect of a meteorite with a small perihelion during the last exposure period.

关键词： noble gas cosmic-ray exposure age meteorite chondrite Zhuanghe Liaoning.