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NUMERICAL PREDICTION OF liNE BUOYANT JETS IN CROSS FLOw.

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Journal of Hydrodynamics 2001年第1期13卷 12-16页

作者： Han, H.L. li, w. Sch. of Urban and Rural Construction Hebei Agriculture Univ. Baoding 071001 China

The k-Ε turbulence model w.s used to establish the mathematical model of tw.-dimensional line buoyant jets in crossflow. The hybrid finite analytic method and staggered grid w.re applied to the calculation of line buoyant jets. Only receiving w.ter w.th uniform density is considered. The distribution of velocity, temperature and turbulent kinetic energy w.re analyzed, and the variation of the maximum velocity w.s given. The effect of velocity ratio and densimetric Froude number on line buoyant jets w.s considered.

关键词： Computational fluid dynamics Computer simulation Diffusers (fluid) Mathematical models Numerical methods

EXPERIMENTAL STUDY ON INSTANTANEOUS DISCHARGE OF UNSORTED PARTICLE CLOUD IN CROSS-FLOw

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Journal of Hydrodynamics 2008年第1期20卷 10-16页

作者： GU Jie HUANG Jing liC. w. College of Marine Science and Technology Shanghai Fisheries University Shanghai 200090 China Department of Civil and Structural Engineering The Hong Kong Polytechnic University Hong Kong China

A series of extensive laboratory experiments w.re conducted to investigate the transport and mixing of instantaneous discharge of unsorted particle cloud in cross-flow. The follow.ng experimental results w.re obtained：（1） the vertical frontal position and the longitudinal w.dth of the particle cloud in the cross-flow.is much larger than those in stagnant w.ter, （2） the smaller cross-flow.velocity w.ll normally cause the larger non-dimensional frontal position for the same particle size range and initial volume, （3） the non-dimensional longitudinal w.dth of the particle cloud in the cross-flow.increases w.th the increase of cross-flow.velocity. The empirical constants （α1, α3 and α2） and their variance range, w.ich can be used to determine the relationships of non-dimensional vertical frontal position and time, longitudinal w.dth and time, and vertical frontal position and longitudinal w.dth w.re also obtained through the analysis of experimental data.

关键词： instantaneous discharge particle cloud cross-flow buoyancy hydrodynamic behavior

THREE-DIMENSIONAL LARGE EDDY SIMULATION OF FREE SURFACE TURBULENT FLOw.IN OPEN CHANNEL w.THIN SUBMERGED VEGETATION DOMAIN

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Journal of Hydrodynamics 2003年第3期15卷 35-43页

作者： SuXiao-hui liC.w.ChenBi-hong CollegeofCivilandHydraulicEngineering DalianUniversityofTechnologyDalian116024China DepartmentofCivilandStructuralEngineering HongKongPolytechnicUniversityHongKongChina

A three-dimensional Large Eddy Simulation (LES) has been performed ofhydrodynamic behavior of turbulent flow.in open channel that the low.r part of the domain isoccupied by a drag force layer to represent vegetation. One equation model is used to closing theresolvable scale equations. The turbulent characteristic length is parameterized by a k-l model. Aphenomenal model is employed to express the performance of vegetation in the open channel. Theresult reveals that the present model has the capacity of describing three-dimensional structure oflarge eddy appearing in turbulent flow.in open channel w.th vegetation region and has the capacityof tracing the development of large eddies.

关键词： LES turbulent flow open channel vegetation

Niobium-tantalum Fractionation During Slab Subduction:Implications for the Formation of Continental Crust

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矿物岩石地球化学通报 2007年第Z1期26卷 61-62页

作者： Yilin Xiao w.idong Sun Jochen Hoefs Klaus Simon Zeming Zhang Shuguang li Albrecht w. Hofmann CAS Key Laboratory of Crust-Mantle and Environments School of Earth and Space Sciences University of Science and Technology of China Hefei 230026 China Geow.ssenschaftliches Zentrum der Universit(a)t G(o)ttingen Geldschmittstrasse 1 D- 37077 G(o)ttingen Germany Key Laboratory of Isotope Geochronology and Geochemistry Guangzhou Institut of Geochemistry Chinese Academy of Sciences Wushan Guangzhou 510640China Max-Planck Institute fuer Chemie Postfach 3060 D-55020 Mainz Germany Geow.ssenschaftliches Zentrum der Universit(a)t G(o)ttingen Geldschmittstrasse 1 D- 37077 G(o)ttingen Germany Institute of Geology Chinese Academy of Geological Sciences Beijing 100037 China CAS Key Laboratory of Crust-Mantle and Environments School of Earth and Space Sciences University of Science and Technology of China Hefei 230026 China Max-Planck Institute fuer Chemie Postfach 3060 D-55020 Mainz Germany

　　Compared w.th the oceanic crust, know.edge about the formation of the continental crust (CC) is relatively poor. Although melting of subducted slabs in the early history of the Earth has been considered as the major w.y that shaped the chemical characteristics of the CC by most geologists, as the CC shares many characteristics w.th modern adakites, some geologists argued that Archean TTG w.s formed in the same w.y as modern arcs rather than slab melting, w.ereas others proposed that melting at the bottom of the thickened oceanic crust w.s more important. Recently,the debate is mainly focused on the unique subchondritic Nb/Ta value of the CC, and particularly, how.Nb and Ta fractionated from each other and consequently how. in detail, the CC w.s built.……

关键词： niobium-tantalum fractionation slab subduction formation of continental crust

FRAGMENTATION ANALYSIS OF OliGONUCLEOTIDES BY MATRIX-ASSISTED LASER DESORPTION/IONIZATION (MALDI) MASS SPECTROMETRY

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质谱学报 1999年第Z1期 77-78页

作者： Y. C. Leo li, T. w. Dominic Chan (Department of Chemistry, Chinese University of Hong Kong Shatin, New.Territories, The Chinese University of Hong Kong, Shatin, New.Territories, Hong Kong)

Interpretable Machine Learning Method for Compressive Strength Prediction and Analysis of Pure Fly Ash-based Geopolymer Concrete

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Journal of w.han University of Technology(Materials Science) 2025年第1期40卷 65-78页

作者： SHI Yuqiong li Jingyi ZHANG Yang li li Key Laboratory of Agricultural Soil and w.ter Engineering in Arid and Semiarid Areas of Ministry of Education Northwest A&F Uni-versityYangling 712100China College of w.ter Resources and Architectural Engineering Northwest A&F UniversityYangling 712100China Chongqing Key Laboratory of Public Big Data Security Technology Chongqing 401420China Chongqing College of Mobile Communication Chongqing 401520China Department of Civil and Environmental Engineering The Hong Kong Polytechnic UniversityHung HomKowloonHong KongChina National Rail Transit Electrification and Automation Engineering Technology Research Center(Hong Kong Branch) The Hong Kong Polytechnic UniversityKowloonHung HomHong KongChina

In order to study the characteristics of pure fly ash-based geopolymer concrete(PFGC)conveniently,w. used a machine learning method that can quantify the perception of characteristics to predict its compressive *** this study,505 groups of data w.re collected,and a new.database of compressive strength of PFGC w.s *** order to establish an accurate prediction model of compressive strength,five different types of machine learning netw.rks w.re used for comparative *** five machine learning models all show.d good compressive strength prediction performance on *** them,R2,MSE,RMSE and MAE of decision tree model(DT)are 0.99,1.58,1.25,and 0.25,*** R2,MSE,RMSE and MAE of random forest model(RF)are 0.97,5.17,2.27 and 1.38,*** tw. models have high prediction accuracy and outstanding generalization *** order to enhance the interpretability of model decision-making,w. used importance ranking to obtain the perception of machine learning model to 13 *** 13 variables include chemical composition of fly ash(SiO_(2)/Al_(2)O_(3),Si/Al),the ratio of alkaline liquid to the binder,curing temperature,curing durations inside oven,fly ash dosage,fine aggregate dosage,coarse aggregate dosage,extra w.ter dosage and sodium hydroxide *** temperature,specimen ages and curing durations inside oven have the greatest influence on the prediction results,indicating that curing conditions have more prominent influence on the compressive strength of PFGC than ordinary Portland cement *** importance of curing conditions of PFGC even exceeds that of the concrete mix proportion,due to the low.reactivity of pure fly ash.

关键词： machine learning pure fly ash geopolymer compressive strength feature perception

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儿童面部烧伤瘢痕的压力治疗研究进展

中华烧伤杂志 2017年第5期33卷 277-280页

作者：魏亚婷付晋凤李曾慧平昆明医科大学第二附属医院烧伤科 650101 昆明医科大学附属儿童医院烧创伤整形科香港理工大学康复治疗科学系

烧伤是儿童最常见的外伤之一，在我国儿童意外损伤中排名前3。儿童面部烧伤导致的面部瘢痕挛缩畸形可影响患儿自我认知及心理发育，并且随着患儿的年龄增长而产生持续长期的负面作用，导致其社会心理功能受损，行为障碍，降低其长远的... 详细信息

烧伤是儿童最常见的外伤之一，在我国儿童意外损伤中排名前3。儿童面部烧伤导致的面部瘢痕挛缩畸形可影响患儿自我认知及心理发育，并且随着患儿的年龄增长而产生持续长期的负面作用，导致其社会心理功能受损，行为障碍，降低其长远的生活质量。

关键词：烧伤儿童面部瘢痕压力治疗

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任意截面形状薄壁压杆的稳定

土木工程学报 1996年第6期29卷 14-24页

作者：王全凤李华煜华侨大学香港理工大学

根据位移变分原理,本文用一个称作为样条有限杆元法的综合方法对任意截面形状的薄壁压杆进行屈曲分析.提出了一个经过变换的三次B样条函数来模拟薄壁压杆横截面纵向翘曲位移.屈曲分析考虑了反映剪力滞后现象的杆壁中面上剪应变的影响.... 详细信息

根据位移变分原理,本文用一个称作为样条有限杆元法的综合方法对任意截面形状的薄壁压杆进行屈曲分析.提出了一个经过变换的三次B样条函数来模拟薄壁压杆横截面纵向翘曲位移.屈曲分析考虑了反映剪力滞后现象的杆壁中面上剪应变的影响.与经典理论及有限单元法的结果比较,表明本文方法能够灵活、精确和有效地进行薄壁杆的稳定分析.数值算例的快速收敛说明了本文数值结果的可靠性.

关键词：薄壁压杆屈曲分析稳定分析

慢性后负荷增加对先天性左室流出道梗阻患者左室心肌功能的影响

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世界核心医学期刊文摘(心脏病学分册) 2007年第9期 32-33页

作者： Lam Y.-Y. Kaya M.G. li w. 杜媛 AdultCongenital Heart Unit Royal Brompton Hospital London United Kingdom

本研究观察了压力超负荷距离对先天性主动脉缩窄和主动脉瓣狭窄(AS)患者左室(LV)功能的影响。利用M型超声和组织多普勒成像(TDI)技术测定连续46例LV流出道梗阻患者(23例主动脉缩窄和23例AS)

关键词：患者 AS 主动脉缩窄主动脉狭窄先天性心脏病后负荷压力负荷收缩幅度收缩速度功能