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CK-Modes Clustering Algorithm Based on Node Cohesion in Labeled Property Graph

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Journal of Computer Science & Technology 2019年第5期34卷 1152-1166页

作者： Da-Wei Wang Wan-Qiu Cui biao qin School of Information Renmin University of ChinaBeijing 100872China School of Computer Science Beijing University of Posts and TelecommunicationsBeijing 100876China

The designation of the cluster number K and the initial centroids is essential for K-modes clustering algorithm. However, most of the improved methods based on K-modes specify the K value manually and generate the initial centroids randomly, which makes the clustering algorithm significantly dependent on human-based decisions and unstable on the iteration time. To overcome this limitation, we propose a cohesive K-modes (CK-modes) algorithm to generate the cluster number K and the initial centroids automatically. Explicitly, we construct a labeled property graph based on index-free adjacency to capture both global and local cohesion of the node in the sample of the input datasets. The cohesive node calculated based on the property similarity is exploited to split the graph to a K-node tree that determines the K value, and then the initial centroids are selected from the split subtrees. Since the property graph construction and the cohesion calculation are only performed once, they account for a small amount of execution time of the clustering operation with multiple iterations, but significantly accelerate the clustering convergence. Experimental validation in both real-world and synthetic datasets shows that the CK-modes algorithm outperforms the state-of-the-art algorithms.

关键词： cluster number property graph index-free adjacency K-node tree cohesive node

Effect of Heat Treatment on Structure and Electrochemical Properties of Electro-deposited Ni-P Amorphous Alloy

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材料热处理学报 2004年第05B期25卷 1163-1165页

作者： GUOJin-biao WANGYu LIHui-qin SUNDong-bai BeijingUniversityofScienceandTechnology Beijing.China

The influences of heat treatment time on structure and the electrochemical behavior of electro-deposited amorphous Ni-P alloy coating were studied. The results show that the as-plated deposits have an amorphous structure, and the deposits crystallize into Ni12P5 and Ni3P at 260 °C, and the corrosion resistance of the as-plated deposits are better than that of the deposits after heat treatment.

关键词：热处理 Ni-P非晶形合金电化学电解沉积

Hemispherical resonator with low subsurface damage machined by small ball-end fine diamond grinding wheel:A novel grinding technique

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Chinese Journal of Aeronautics 2024年第5期37卷 570-585页

作者： biao qin Henan LIU Jian CHENG Jinchuan TIAN Jiangang SUN Zihan ZHOU Chuanzhen MA Mingjun CHEN State Key Laboratory of Robotics and System Harbin Institute of TechnologyHarbin 150001China Center for Precision Engineering Harbin Institute of TechnologyHarbin 150001China

As for the ultra-precision grinding of the hemispherical fused silica resonator,due to the hard and brittle nature of fused silica,subsurface damage(SSD)is easily generated,which enormously influences the performance of such ***,ultra-precision grinding experiments are carried out to investigate the surface/subsurface quality of the hemispherical resonator machined by the small ball-end fine diamond grinding *** influence of grinding parameters on the surface roughness(SR)and SSD depth of fused silica samples is then *** experimental results indicate that the SR and SSD depth decreased with the increase of grinding speed and the decrease of feed rate and grinding *** addition,based on the material strain rate and the maximum undeformed chip thickness,the effect of grinding parameters on the subsurface damage mechanism of fused silica samples is ***,a multi-step ultra-precision grinding technique of the hemispherical resonator is proposed based on the interaction influence between grinding depth and feed ***,the hemispherical resonator is processed by the proposed grinding technique,and the SR is improved from 454.328 nm to 110.449 nm while the SSD depth is reduced by 94%from 40μm to 2.379μ*** multi-step grinding technique proposed in this paper can guide the fabrication of the hemispherical resonator.

关键词： Fused silica Ultra-precision grinding Hemispherical resonator Subsurface damage Grinding technique

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基于热分析技术的球墨铸铁组织性能预测

铸造 2025年第1期74卷 16-25页

作者：杨湘杰李锟杨明浩邓博焰刘钦标叶寒南昌大学先进制造学院江西南昌330031 江西省高性能精确成形重点实验室江西南昌330031

通过单变量试验分别研究了不同新型球化剂、孕育剂加入后的球墨铸铁热分析曲线特征值对收缩倾向及球化效果的影响规律,并利用SPSS回归分析软件建立了曲线特征值与收缩倾向、球化率关联性的数学模型。研究结果表明,在其他因素相同时,共... 详细信息

通过单变量试验分别研究了不同新型球化剂、孕育剂加入后的球墨铸铁热分析曲线特征值对收缩倾向及球化效果的影响规律,并利用SPSS回归分析软件建立了曲线特征值与收缩倾向、球化率关联性的数学模型。研究结果表明,在其他因素相同时,共晶再辉温度ΔT越大,共晶反应速度越快,平均石墨球数越少,球化级别越差;球化率、石墨球数随着共晶最低温度TEU的升高而逐渐上升。前期收缩时间比例G1/G所占的时间越长,被测铁液的缩孔率越大;石墨化膨胀时间比例G2/G越长,则被测缩松率越大;并且建立了曲线特征值与收缩倾向、球化率的数学模型,该模型能够准确预测球化率和收缩倾向。

关键词：球墨铸铁热分析技术收缩倾向球化效果金相图像处理

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Long-term Development Prospects and Suggestions for Domestic Refined Oil Market

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China Oil & Gas 2024年第4期31卷 30-39页

作者： Kong Jingyuan qin biao Li Mingjiang PetroChina Planning and Engineering Institute PetroChina Hainan Marketing Company

Over the past decade,China’s refined oil market has experienced considerable growth and *** consumption has generally followed the growth rate of vehicle equipment,with fluctuations influenced by travel frequency;aviation fuel consumption has seen stable growth following the end of COVID-19,while diesel consumption has been affected by multiple factors including demand and *** the rapid development of new energy vehicles and alternative fuels,the gasoline and diesel market has essentially peaked,yet domestic production of refined oil continues to grow,leading to an increasingly prominent oversupply *** achieve the dual carbon goals,the Chinese government has introduced a series of policies that have a profound impact on the refined oil *** resource surplus and market demand changes,the refining industry needs to optimize production capacity structure,and oil products retail companies face transformation *** article aims to provide market analysis and recommendations,serving as a reference for relevant enterprises and policymakers.

关键词： companies refined aviation

Cloning and Expression Pattern of a Gene Encoding a Putative Plastidic ATP/ADP Transporter from Helianthus tuberosus L.

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Journal of Integrative Plant Biology 2005年第9期47卷 1123-1132页

作者： Kun MENG Tuan-Jie CHANG Xiang LIU Song-biao CHEN Yong-qin WANG Ai-Jun SUN Hong-Lin XU Xiao-Li WEI Zhen ZHU Institute of Genetics and Developmental Biology the Chinese Academy of Sciences Beijing 100101 China

Herein, we report the cloning and molecular characterization of a full cDNA encoding a putative plastidic ATP/ADP transporter, designated HtAATP, for Helianthus tuberosus L. The ATP/ADP translocator protein was isolated from the tuber-cDNA library of H. tuberosus for the first time. The predicted HtAATP protein was judged as a plastidic ATP/ADP translocator protein from its high homology at the amino acid sequence level to the two Arabidopsis thaliana plastidic ATP/ADP translocator proteins AATP1 and AATP2 （84.8% and 79.9% identity, respectively）. Amino acid sequence analysis of the primary structure of HtAATP revealed that it belonged to the plastidic ATP/ADP transporter family. Hydropathy prediction indicated that HtAATP gene product is a highly hydrophobic membrane protein that contains 10 transmembrane domains to form a spanning topology. Southern blotting analysis showed that the HtAATP gene is a single-copy gene in the H. tuberosus genome. Tissue distribution analysis showed that the HtAATP gene is prominently expressed in sink tissues. A stable expression pattern in tubers at different developmental stages implies an active involvement of HtAATP during carbohydrate formation.

关键词： expression pattern Helianthus tuberosus plastidic ATP/ADP transporter.

新疆阿勒吞昆多蛇绿混杂岩的地球化学特征及形成环境

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西北地质 2013年第2期46卷 30-36页

作者：秦彪中国建筑材料工业地质勘查中心新疆总队新疆乌鲁木齐830000

该蛇绿混杂岩的岩石组合为辉长岩、斜长花岗岩及火山熔岩等,缺失变质橄榄岩、超镁铁堆晶岩和辉绿岩岩墙单元。蛇绿岩中辉长岩和基性熔岩REE球粒陨石标准化和微量元素原始地幔标准化分配型式呈近平坦型分布,轻稀土亏损或略亏损,类似于岛... 详细信息

该蛇绿混杂岩的岩石组合为辉长岩、斜长花岗岩及火山熔岩等,缺失变质橄榄岩、超镁铁堆晶岩和辉绿岩岩墙单元。蛇绿岩中辉长岩和基性熔岩REE球粒陨石标准化和微量元素原始地幔标准化分配型式呈近平坦型分布,轻稀土亏损或略亏损,类似于岛弧(IAB)和扩张脊(MORB)过渡构造背景特征,形成于SSZ型洋盆底初始岛弧的弧前扩张环境。

关键词：新疆东准噶尔阿勒吞昆多古亚洲洋蛇绿岩洋中脊

阿勒吞昆多蛇绿混杂岩斜长花岗岩锆石SHRIMP测年及时限

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西北地质 2012年第3期45卷 20-25页

作者：秦彪中国建筑材料工业地质勘查中心新疆总队新疆乌鲁木齐830000

在大量查阅分析和研究前人资料基础上,提出阿勒吞昆多蛇绿混杂岩是卡拉麦里蛇绿岩带的向东延伸部分。卡拉麦里蛇绿岩带西起卡拉麦里—塔克扎勒—大黑山至伊吾县阿勒吞昆多一带,向东可能延伸至蒙古境内。该蛇绿混杂岩中斜长花岗岩产于辉... 详细信息

在大量查阅分析和研究前人资料基础上,提出阿勒吞昆多蛇绿混杂岩是卡拉麦里蛇绿岩带的向东延伸部分。卡拉麦里蛇绿岩带西起卡拉麦里—塔克扎勒—大黑山至伊吾县阿勒吞昆多一带,向东可能延伸至蒙古境内。该蛇绿混杂岩中斜长花岗岩产于辉长岩顶部,二者呈突变或渐变接触关系。应用SHRIMP方法对斜长花岗岩进行了锆石U-Pb定年,获得了(351±6Ma)的年龄,这一年龄反映阿勒吞昆多蛇绿岩形成于早石炭世。同时,该蛇绿混杂岩上覆岩系的时代为晚石炭世,表明阿勒吞昆多蛇绿混杂岩侵位时代不晚于晚石炭世。

关键词：斜长花岗岩蛇绿混杂岩侵位时限上覆岩系

Multi boron-doping effects in hard carbon toward enhanced sodium ion storage

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Journal of Energy Chemistry 2025年第1期100卷 730-738页

作者： Peng Zheng Wang Zhou Ying Mo biao Zheng Miaomiao Han qin Zhong Wenwen Yang Peng Gao Lezhi Yang Jilei Liu College of Materials Science and Engineering Hunan Joint International Laboratory of Advanced Materials and Technology for Clean EnergyHunan Province Key Laboratory for Advanced Carbon Materials and Applied TechnologyHunan UniversityChangsha 410082HunanChina Greater Bay Area Institute for Innovation Hunan UniversityGuangzhou 511300GuangdongChina Changsha Research Institute of Mining&Metallurgy Co. LTD.Changsha 410017HunanChina

Hard carbon (HC) has been considered as promising anode material for sodium-ion batteries (SIBs).The optimization of hard carbon’s microstructure and solid electrolyte interface (SEI) property are demonstrated effective in enhancing the Na+storage capability,however,a one-step regulation strategy to achieve simultaneous multi-scale structures optimization is highly ***,we have systematically investigated the effects of boron doping on hard carbon’s microstructure and interface chemistry.A variety of structure characterizations show that appropriate amount of boron doping can increase the size of closed pores via rearrangement of carbon layers with improved graphitization degree,which provides more Na+storage ***-situ Fourier transform infrared spectroscopy/electrochemical impedance spectroscopy (FTIR/EIS) and X-ray photoelectron spectroscopy (XPS) analysis demonstrate the presence of more BC3and less B–C–O structures that result in enhanced ion diffusion kinetics and the formation of inorganic rich and robust SEI,which leads to facilitated charge transfer and excellent rate *** a result,the hard carbon anode with optimized boron doping content exhibits enhanced rate and cycling *** general,this work unravels the critical role of boron doping in optimizing the pore structure,interface chemistry and diffusion kinetics of hard carbon,which enables rational design of sodium-ion battery anode with enhanced Na+storage performance.

关键词： Hard carbon Sodium-ion batteries Boron doping Pore structure Electrode/electrolyte interphases