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A particle-resolved heat-particle-fluid coupling model by DEM-IMB-LBM

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第6期16卷 2267-2281页

作者： ming Xia jinlong Fu Y.T.Feng Fengqiang Gong jin Yu Hunan Key Laboratory of Geomechanics and Engineering Safety Xiangtan UniversityXiangtan411105China Zienkiewicz Institute for Modelling Data and AISwansea UniversitySwanseaSA18EPUK School of Civil Engineering Southeast UniversityNanjing211189China Fujian Research Center for Tunneling and Urban Underground Space Engineering Huaqiao UniversityXiamen361021China

Multifield coupling is frequently encountered and also an active area of research in geotechnical *** this work,a particle-resolved direct numerical simulation(PR-DNS)technique is extended to simulate particle-fluid interaction problems involving heat transfer at the grain *** this extended technique,an immersed moving boundary(IMB)scheme is used to couple the discrete element method(DEM)and lattice Boltzmann method(LBM),while a recently proposed Dirichlet-type thermal boundary condition is also adapted to account for heat transfer between fluid phase and solid *** resulting DEM-IBM-LBM model is robust to simulate moving curved boundaries with constant temperature in thermal *** facilitate the understanding and implementation of this coupled model for non-isothermal problems,a complete list is given for the conversion of relevant physical variables to lattice ***,benchmark tests,including a single-particle sedimentation and a two-particle drafting-kissing-tumbling(DKT)simulation with heat transfer,are carried out to validate the accuracy of our coupled *** further investigate the role of heat transfer in particle-laden flows,two multiple-particle problems with heat transfer are *** examples demonstrate that the proposed coupling model is a promising high-resolution approach for simulating the heat-particle-fluid coupling at the grain level.

关键词： Particle-fluid interaction Heat transfer Discrete element method(DEM) Lattice Boltzmann method(LBM) Dirichlet-type thermal boundary Direct numerical simulation

Tailoring Ni based catalysts by indium for the dehydrogenative coupling of ethanol into ethyl acetate

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Green Energy & Environment 2024年第8期9卷 1321-1331页

作者： ming Yin Jifeng Pang jin Guo Xianquan Li Yujia Zhao Pengfei Wu mingyuan Zheng CAS Key Laboratory of Science and Technology on Applied Catalysis Dalian Institute of Chemical PhysicsChinese Academy of Sciences University of Chinese Academy of Sciences School of Materials Science and Engineering Dalian Jiaotong University

Exploring stable and robust catalysts to replace the current toxic CuCr based catalysts for dehydrogenative coupling of ethanol to ethyl acetate is a challenging but promising ***,novel NiIn based catalysts were developed by tailoring Ni catalysts with Indium （In） for this *** the optimal Ni0.1Zn0.7Al0.3InOx catalyst,the ethyl acetate selectivity reached 90.1%at 46.2%ethanol conversion under the conditions of 548 K and a weight hourly space velocity of 1.9 h-1in the 370 h time on ***,the ethyl acetate productivity surpassed1.1 gethyl acetateg-1catalysth-1,one of the best performance in current *** to catalyst characterizations and conditional experiments,the active sites for dehydrogenative coupling of ethanol to ethyl acetate were proved to be Ni4In *** presence of In tailored the chemical properties of Ni,and subsequently inhibited the C±C cracking and/or condensation reactions during ethanol *** Ni4In alloy sites,ethanol was dehydrogenated into acetaldehyde,and then transformed into acetyl species with the removal of H ***,the coupling between acetyl species and surface-abundant ethoxyde species into ethyl acetate was achieved,affording a high ethyl acetate selectivity and catalyst stability.

关键词： Dehydrogenative coupling Ethanol Ethyl acetate Nickel and indium alloys

Two-Staged Method for Ice Channel Identification Based on Image Segmentation and Corner Point Regression

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China Ocean Engineering 2024年第2期38卷 313-325页

作者： DONG Wen-bo ZHOU Li DING Shi-feng WANG Ai-ming CAI jin-yan School of Naval Architecture and Ocean Engineering Jiangsu University of Science and TechnologyZhenjiang 212003China School of Naval Architecture Ocean and Civil EngineeringShanghai Jiao Tong UniversityShanghai 200240China

Identification of the ice channel is the basic technology for developing intelligent ships in ice-covered waters,which is important to ensure the safety and economy of *** the Arctic,merchant ships with low ice class often navigate in channels opened up by *** in the ice channel often depends on good maneuverability skills and abundant experience from the captain to a large *** ship may get stuck if steered into ice fields off the *** this circumstance,it is very important to study how to identify the boundary lines of ice channels with a reliable *** this paper,a two-staged ice channel identification method is developed based on image segmentation and corner point *** first stage employs the image segmentation method to extract channel *** the second stage,an intelligent corner regression network is proposed to extract the channel boundary lines from the channel region.A non-intelligent angle-based filtering and clustering method is proposed and compared with corner point regression *** training and evaluation of the segmentation method and corner regression network are carried out on the synthetic and real ice channel *** evaluation results show that the accuracy of the method using the corner point regression network in the second stage is achieved as high as 73.33%on the synthetic ice channel dataset and 70.66%on the real ice channel dataset,and the processing speed can reach up to 14.58frames per second.

关键词： ice channel ship navigation identification image segmentation corner point regression

Solidification behaviour and hot cracking susceptibility of a novel Ni-based superalloy

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Journal of Iron and Steel Research International 2024年第4期31卷 956-966页

作者： Yue Chen Shao-min Lv xing-fei Xie Xiao-can Wen Jng-long Qu jin-hui Du High-Temperature Materials Institute China Iron and Steel Research Institute Group Co.Ltd.Beijing 100081China Beijing GAONA Materials and Technology Co. Ltd.Beijing 100081China Sichuan CISRI-GAONA Forging Co. Ltd.Deyang 610000SichuanChina

A novel Ni-based superalloy GH4151,with a γ′ volume fraction of about 55%and a service temperature capability up to 8oo oC,was *** to the different cooling conditions of various regions during the solidification of ingots,significant cooling rate variations may lead to the occurrence of hot *** scanning laser microscope was utilised to investigate the solidification process and phase precipitation behaviour of the GH4151 under wide range cooling *** characteristics of L→γ transformation were analysed,and the growth rates of at each stage were *** segregation behaviour was predicted using the Scheil equation,and the predicted results match well with the experimental *** sensitivity coefficient for hot cracking was modified,and cracking sensitivity coefficient values for the alloy under different cooling rates were computed,revealing that the alloy is most susceptible to hot cracking at 10℃/min cooling ***,controlling the cooling rate can reduce the possibility of hot cracking in ingot.

关键词： Ni-based superalloy Solidification behaviour In-situ observation Clyne and Davies's criterion:Hot cracking susceptibility

Relative position of seeds driven the seedling growth are mediated by root-leaf traits

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Journal of Plant Ecology 2024年第2期17卷 24-35页

作者： jing Zhu Xue-Lin Wang xing jin Lan Jiang Hong-Yu Lin Yang Hu jin-Fu Liu Zhong-Sheng He College of Forestry Fujian Agriculture and Forestry UniversityFuzhou 350002China Key Laboratory of Fujian Universities for Ecology and Resource Statistics Fujian Agriculture and Forestry UniversityFuzhou 350002China Zhenjiang Natural Resources and Planning Bureau Economic and Technological Development Zone Branch Zhenjiang 212132China

Variations in plant traits are indicative of plant adaptations to forest environments,and studying their relationships with tree growth provides valuable insights into forest *** spatial arrangement of plant seeds within the forest litter or soil critically infuences the variations of root-leaf traits,thereby affecting the adaptive strategies of emerging ***,our current understanding of the impacts of individual root-leaf traits on seedling growth in different relative position,and whether these traits together affect growth,remains *** study focuses on the dominant tree species,Castanopsis kawakamii,within the Sanming *** Nature Reserve of *** present experiment aimed to examine the variations in root-leaf traits of seedling,focus on the relative positions of seeds within different layers:beneath or above the litter layer,or within the bare soil layer(without litter).Our fndings provided evidence supporting a coordinated relationship between root and leaf traits,wherein leaf traits varied in conjunction with root traits in the relative positions of ***,we observed that seedlings exhibited higher values for specifc leaf area and average root diameter,while displaying lower root tissue *** mixed model explained 86.1%of the variation in root-leaf traits,surpassing the variation explained by the relative ***,soil nitrogen acted as a mediator,regulating the relationship between seedling growth and root-leaf traits,specifcally leaf dry matter content and root tissue ***,future studies should consider artifcially manipulating tree species diversity based on root-leaf traits characteristics to promote forest recovery.

关键词： relative growth rate coordination leaf traits root traits soil nitrogen content seed relative positions

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语言迟缓儿童家庭语言环境的研究

上海交通大学学报（医学版） 2009年第7期29卷 775-777页

作者：刘晓金星明沈晓明上海交通大学医学院上海儿童医学中心发育行为儿科上海市环境与儿童健康重点实验室上海200127

目的探讨语言迟缓儿童的不良家庭语言环境因素。方法对上海10个区的24～35月龄健康足月上海户籍儿童进行整群抽样调查。将词汇量少于30定义为语言迟缓。对相关环境因素进行单因素分析和Logistic逐步回归分析。结果有效抽样2774人,检出... 详细信息

目的探讨语言迟缓儿童的不良家庭语言环境因素。方法对上海10个区的24～35月龄健康足月上海户籍儿童进行整群抽样调查。将词汇量少于30定义为语言迟缓。对相关环境因素进行单因素分析和Logistic逐步回归分析。结果有效抽样2774人,检出语言迟缓儿童115人,检出率4.1%。以26个环境因素为自变量进行单因素分析,发现危险因素9项;进一步的Logistic逐步回归分析显示具有统计学意义的危险因素5项,分别为常居住地为城区、父亲文化程度低于初中、使用单一语言、带养人为男性及带养人少与儿童交流。结论避免危险因素及提供良好的家庭语言环境,有助于预防语言迟缓的发生。

关键词：语言迟缓家庭环境因素分析

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2岁儿童语言理解和表达能力相关因素的研究

中华医学杂志 2007年第38期87卷 2689-2692页

作者：刘晓金星明沈晓明上海交通大学医学院附属新华医院上海儿童医学中心发育行为儿科 200127

目的探讨影响表达和理解能力的因素,为早期语言发育迟缓的预防和干预提供依据。方法采用分阶段整群抽样,进行横断面调查。2005年3至8月采用家长问卷在上海8个行政区调查了2794个儿童,以《婴幼儿语言发育进程量表》评估儿童表达和理解得... 详细信息

目的探讨影响表达和理解能力的因素,为早期语言发育迟缓的预防和干预提供依据。方法采用分阶段整群抽样,进行横断面调查。2005年3至8月采用家长问卷在上海8个行政区调查了2794个儿童,以《婴幼儿语言发育进程量表》评估儿童表达和理解得分并分组,根据 Logistic逐步回归模型进行统计分析。结果表达能力的24项可能相关因素中有5项有意义,不利于语言表达能力发育的因素有:不常练习表达(OR=3.0257),平常看书是默看而不"看图说话"(OR=2.0704),男孩(OR=1.7778),看电视不作讨论(OR=1.4424),1岁半后才开始经常看图书(OR=1.1576～2.0115)。理解能力的24项可能相关因素中有11项有意义,不利于理解能力发展的因素有:父亲是农林牧渔水利生产人员(OR=17.0238),不常练习表达(OR=2.8410),常住城市(OR=2.0125),平常看书是默看而不是"看图说话"(OR=1.7039),平均每天看电视时间超过2 h(OR=1.6551),看电视不作讨论(OR=1.5344),照看人和孩子交流少(OR=1.1892),母亲文化水平低于初中(OR=1.1870),男孩(OR=1.6722),平均每周与同伴玩耍次数少于2次(OR=1.1671),1岁半后才开始经常看图书(OR=1.0435～2.0228)。结论影响语言表达和语言理解的相关因素既有重合,又不完全相同。避免各种高危因素有助于防治早期语言发育偏离的发生。

关键词：横断面研究儿童语言发展

A self-driving solution for resource-constrained autonomous vehicles in parked areas

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High-Confidence Computing 2024年第1期4卷 32-42页

作者： jin Qian Liang Zhang Qiwei Huang Xinyi Liu Xiaoshuang xing Xuehan Li College of Information Engineering Taizhou UniversityTaizhou 225300China Engineering Research Center of Integration and Application of Digital Learning Technology Ministry of EducationBeijing 100039China School of Computer Science and Engineering Changshu Institute of TechnologyChangshu 215500China The School of Electronic and Information Engineering Beijing Jiaotong UniversityBeijing 100044China

Autonomous vehicles in industrial parks can provide intelligent,efficient,and environmentally friendly transportation services,making them crucial tools for solving internal transportation *** the characteristics of industrial park scenarios and limited resources,designing and implementing autonomous driving solutions for autonomous vehicles in these areas has become a research *** paper proposes an efficient autonomous driving solution based on path planning,target recognition,and driving decision-making as its core *** designs for path planning,lane positioning,driving decision-making,and anti-collision algorithms are *** analysis and experimental validation of the proposed solution demonstrate its effectiveness in meeting the autonomous driving needs within resource-constrained environments in industrial *** solution provides important references for enhancing the performance of autonomous vehicles in these areas.

关键词： Autonomous vehicles Path planning Target recognition Driving decision-making Self-driving

Effect of multiple coulomb scattering on the beam tests of silicon pixel detectors

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Nuclear Science and Techniques 2024年第4期35卷 200-207页

作者： Lan-Kun Li ming-Yi Dong Ze Gao Liang-Cheng-Long jin Shu-Jun Zhao School of Physics and Microelectronics Zhengzhou UniversityZhengzhou 450001China State Key Laboratory of Particle Detection and Electronics(Institute of High Energy Physics CAS)Beijing 100049China University of Chinese Academy of Science Beijing 100049China University of South China Hengyang 421001China

In the research and development of new silicon pixel detectors,a collimated monoenergetic charged-particle test beam equipped with a high-resolution pixel-beam telescope is crucial for prototype verification and performance *** the beam energy is low,the effect of multiple Coulomb scattering on the measured resolution of the Device Under Test(DUT)must be considered to accurately evaluate the performance of the pixel chips and *** study aimed to investigate the effect of multiple Coulomb scattering on the measured resolution,particularly at low beam *** were conducted using Allpix^(2) to study the effects of multiple Coulomb scattering under different beam energies,material budgets,and telescope *** simulations also provided the minimum energy at which the effect of multiple Coulomb scattering could be *** with the results of a five-layer detector system tested with an electron beam at DESY,the simulation results were consistent with the beam test results,confirming the reliability of the simulations.

关键词： Silicon Pixel Detectors Beam Telescope Multiple Coulomb Scattering Spatial Resolution