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Analysis of 3D curve expansion of conical cam with oscillating tapered roller follower

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2007年第11期8卷 1789-1794页

作者： CHEN Jun-hua WU yi-jie Ningbo Institute of Technology Zhejiang University Ningbo 315010 China Institute of Modern Manufacture Engineering Zhejiang University Hangzhou 310027 China

This paper focuses on the analysis of running conditions and machining processes of conical cam with oscillating follower. We point out the common errors existing in the design and machining of the widely used plane expansion method of conical cam trough-out line. We show that the motion can be divided into two parts, i.e. the oscillating motion of oscillating bar and the rotary motion of oscillating bar relative to the conical cam. By increasing the rotary motion of oscillating bar, the motion path of tapered roller on oscillating bar (i.e. contour surface of conical cam) can be expanded on the cylinder. Based on these analyses, we present a creative and effective designing and machining method for 3D curve expansion of conical cam with oscillating follower.

关键词： Oscillating follower Conical cam Tapered roller plane expansion 3D curve expansion

Research in non-equalization machining method for spatial cam

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2008年第9期9卷 1258-1263页

作者： Jun-hua CHEN yi-jie WU Institute of Mechanical and Electrical Engineering Ningbo Institute of Technology Zhefiang University Ningbo 315010 China Institute of Modern Manufacture Engineering Zhejiang University Hangzhou 310027 China

Many kinds of devices with cam have been widely used in various mechanical equipments. However, non-equalization machining for spatial cam trough remains to be a difficult problem. This paper focuses on the analysis of running conditions and machining processes of spatial cam with oscillating follower. We point out the common errors in the biased distance cutting. By analyzing the motion of oscillating follower of spatial cam, we present a new 3D curve expansion model of spatial cam trough-outline. Based on this model, we have proposed a machining method for trochoidal milling with non-equalization diameter cutter. This new method has led to a creative and effective way for non-equalization diameter machining for spatial cam with oscillating follower.

关键词： Oscillating follower Spatial cam 3D curve exoansion Trochoidal milling Non-eaualization diameter

Topological Recursion Relations from Pixton Relations

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Acta Mathematica Sinica,English Series 2017年第4期33卷 470-494页

作者： yi jie LIN Jian ZHOU Department of Mathematical Sciences Tsinghua University Beijing 100084 P. R. China

We propose an algorithm to derive tautological relations from Pixton relations. We carry out this algorithm explicitly to derive some results in genus 0, 1, 2, 3 and analyze the possibility to generalize to higher gen... 详细信息

关键词： Faber–Zagier relations Pixton relations topological recursion relations Gromov–Witten invariants

CONTROL OF DIMENSIONAL STABILITY AND DEGRADATION RATE IN ELECTROSPUN COMPOSITE SCAFFOLDS COMPOSED OF POLY(D,L-LACTIDE-co-GLYCOLIDE) AND POLY(ε-CAPROLACTONE)

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Chinese Journal of Polymer Science 2008年第1期26卷 63-71页

作者： yi-jie Liu Hong-liang Jiang Yan Li Kang-jie Zhu Department of Polymer Science and Engineering Zhejiang UniversityHangzhou 310027China

The purpose of this study is to investigate the effect of composition poly(D,L-lactide-co-glycolide)/poly(ε- caprolactone)(PLGA/PCL)blending on the morphology,shrinkage and degradation behaviors of the electrospun fibers. With the increase of PLGA content in the composite fibers,the average diameter of the electrospun fibers increased from 1.35μm to 1.95μ*** serious shrinking of the electrospun PLGA meshes could be circumvented by adding 20% PCL in the fibers,resulting from the semi-crystalline nature of ...

关键词： Electrospun PCL PLGA Shrinkage Degradation

Thermogravimetric study of combustion of biomass and anthracite coal by iso-conversional method

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Journal of Iron and Steel Research International 2018年第3期25卷 330-339页

作者： Dong Wang Si-yi Luo Yang-min Zhou Chui-jie yi National and Local Joint Engineering Research Center of Metallurgical Slag Efficient Resource Utilization QingdaoTechnological University Qingdao 266520 Shandong China

The combustion characteristics of biomass, anthracite coal and their blends were investigated using thermogravimetry, and the kinetic parameters and combustion reaction mechanisms were tested by combining the iso-conversional method and Avrami method in order to find out the kinetics characteristics responsible for the combustion of samples. In biomass combustion, two peaks were observed at 332.3 and 472.3℃, but the reactive rate curve of coal showed one peak with maximum mass loss rate at 552.8℃. The ignition temperature and burnout temperature of blends decreased, and the ignition index and combustibility index increased with the increase in biomass content. Calculation of kinetic parameters showed that the values of activation energy of blends increased with increasing biomass content from 150.77 to 215.93 kJ/mol. The reaction orders of blends lay in the range of 0.44 and 0.78.

关键词： Biomass-Pulverized coal Combustion-Kinetics Thermogravimetry Iso-conversional method

Vectorial approximations of infinite-dimensional covariance descriptors for image classification

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Computational Visual Media 2017年第4期3卷 379-385页

作者： jie-yi Ren Xiao-Jun Wu School of Io T Engineering Jiangnan UniversityWuxi 214122China

The class of symmetric positive definite(SPD)matrices,especially in the form of covariance descriptors(Cov Ds),have been receiving increased interest for many computer vision *** descriptors offer a compact way of robustly fusing different types of features with measurement *** examples of applying Cov Ds addressing various classification problems

关键词： covariance infinite Riemannian symmetric matrices applying dimensionality classifier Euclidean kernel

A skew–normal mixture of joint location, scale and skewness models

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Applied Mathematics(A Journal of Chinese Universities) 2016年第3期31卷 283-295页

作者： LI Hui-qiong WU Liu-cang yi jie-yi Department of statistics Yunnan University Faculty of Science Kunming University of Science and Technology School of Mathematical Sciences Beijing Normal University

Normal mixture regression models are one of the most important statistical data analysis tools in a heterogeneous population. When the data set under consideration involves asymmetric outcomes, in the last two decades, the skew normal distribution has been shown beneficial in dealing with asymmetric data in various theoretic and applied problems. In this paper, we propose and study a novel class of models： a skew-normal mixture of joint location, scale and skewness models to analyze the heteroscedastic skew-normal data coming from a heterogeneous population. The issues of maximum likelihood estimation are addressed. In particular, an Expectation-Maximization （EM） algorithm for estimating the model parameters is developed. Properties of the estimators of the regression coefficients are evaluated through Monte Carlo experiments. Results from the analysis of a real data set from the Body Mass Index （BMI） data are presented.

关键词： mixture regression models mixture of joint location scale and skewness models EM algorithm maximum likelihood estimation skew-normal mixtures

Catalytic oxidation of ethyl acetate on Ce-Mn-O catalysts modified by La

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Rare Metals 2021年第3期40卷 547-554页

作者： yi-jie Lao Xing-Xing Jiang Ju Huang Zhen Zhang Xing-yi Wang Lab for Advanced Materials Research Institute of Industrial CatalysisSchool of Chemistry and Molecular EngineeringEast China University of Science and TechnologyShanghai 200237China

La/Ce_(0.5)Mn_(0.5) catalysts prepared by wetness impregnation of Ce_(_(0.5))Mn_(_(0.5)) with La(NO_(3))_(3)(aq) were used in catalytic oxidation of ethyl *** by X-ray diffractometer(XRD),H2 temperature programmed reduction(H2-TPR),X-ray photoelectron spectroscopy(XPS) and Raman shows that La/Ce_(0.5)Mn_(0.5) catalysts have fluorite-like ***_(0.5)Mn_(0.5) catalyst presents high activity with T90(the temperature needed for 90% conversion) of 200℃,where ethyl acetate is almost completely converted into CO_(2).The conversion at 195℃ maintains at 80% for at least 100 *** intermediates were mainly ethanol and acetaldehyde whose amounts are below250 × 10^(-6) and 16 × 10^(-6),*** situ FTIR indicates that the modes of dissociative adsorption of ethyl acetate are related to surface oxygen species,which affect the stability of catalysts and the selectivity for ethanol and acetaldehyde intermediates.

关键词： Ethyl acetate Catalytic combustion Ceria Lanthanum Manganese

NASICON solid electrolyte coated by indium film for all-solid-state Li-metal batteries

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Tungsten 2022年第4期4卷 316-322页

作者： yi-jie Liu Ru-yi Fang David Mitlin Materials Science and Engineering Program and Texas Materials Institute The University of Texas at AustinAustinTX78712USA

The application of all-solid-state Li-metal batteries with solid oxide electrolytes is hindered by interfacial issues,especially the solid electrolyte/Li-metal *** work introduced a uniform indium film layer on the surface of Na^(+)super ionic conductor(NASICON)solid electrolyte Li_(1.5)Al_(0.5)Ge_(1.5)P_(3)O_(12)(LAGP),which promotes the intimate contact between Li metal and solid electrolyte and hinders the side reactions at the *** impedance spectra show that the battery with coated solid electrolyte presents a smaller interfacial resistance and maintains stability after a long cycling *** contrast,the baseline battery with a pure LAGP pellet shows a contact loss after cycling with the vibration of interfacial *** Li symmetric cells with indium-modified solid electrolyte present stable cycling behavior over 400 h at 0.1 and 0.2 mA·cm^(−2).The all-solid-state Li-metal batteries with a Li anode,indium coating LAGP and two kinds of cathodes,namely carbon nanotubes(CNTs)and LiNi_(0.8)Co_(0.1)Mn_(0.1)O_(2)(NCM811),are prepared and *** CNTs cathode for Li-O2 and Li-air batteries has a higher specific capacity than traditional Li-ion battery *** Li-NCM811 batteries deliver an initial Coulombic efficiency of about 75%,with 82%capacity retention after 20 cycles.

关键词： All-solid-state batteries Solid electrolyte Li1.5Al0.5Ge1.5P3O12 Li-metal anode Interfacial chemistry