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充填土袋堤变形与稳定离心模型试验研究

工程勘察 2014年第11期42卷 1-5页

作者：王年香顾行文任国峰高长胜朱群峰南京水利科学研究院南京210024

利用疏浚土及吹填泥作为充填料的土工织物充填袋筑堤技术得到极大关注。本文针对连云港疏浚土,采用土工离心模型试验技术,研究充填土袋堤体与地基的变形和整体稳定性。试验结果表明:充填土袋堤沉降主要发生在施工期,竣工后沉降变化很小... 详细信息

利用疏浚土及吹填泥作为充填料的土工织物充填袋筑堤技术得到极大关注。本文针对连云港疏浚土,采用土工离心模型试验技术,研究充填土袋堤体与地基的变形和整体稳定性。试验结果表明:充填土袋堤沉降主要发生在施工期,竣工后沉降变化很小,在堤体范围内沉降呈堤中心大、两边小的锅形分布。充填土黏粒含量对堤身的压缩变形影响较大,充填黏性土与充填砂性土相比,竣工期堤身压缩变形约高11%,竣工一个月后堤身压缩变形约高13%。堤体与地基失稳破坏为圆弧滑动破坏型式,充填黏性土堤稳定安全系数为1.19,充填砂性土堤的稳定安全系数为1.41,表明充填黏粒含量高达32.5%的黏性土筑堤能满足整体稳定要求。

关键词：充填土袋堤变形与稳定黏粒含量离心模型试验

Impact of different human walking patterns on flow and contaminant dispersion in residential kitchens:Dynamic simulation study

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Building Simulation 2022年第6期15卷 1051-1066页

作者： Lipeng Lv Yuhang Wu changsheng Cao Lingjie Zeng Jun gao Wuhao Xie Jing Zhang Institute of HVAC Engineering School of Mechanical EngineeringTongji UniversityShanghai200092China College of Environmental Science and Engineering Tongji UniversityShanghai200092China

The effects of different human walking patterns on contaminant dispersion in residential kitchens were investigated through computational fluid dynamics simulation with the dynamic mesh method.A tracer gas experiment was performed to verify the feasibility and accuracy of the simulation *** characteristics induced by human walking were minutely described,and the transient capture efficiency of the range hood was adopted to assess the impact of human walking *** walking parallel to a counter,human walking parallel to a counter manned by another human,and human walking toward a counter were *** showed that the mutual effect of the wake and thermal plume caused contaminant dispersion and decreased the performance of the range hood as the human subject walked beside the *** a standing person operated ahead the counter,the wake would affect the thermal plume in a certain *** decrement of capture efficiency approached 0.5 in the most unfavorable ***,the coaction of the positive/negative pressure zone and impinging air jet drew the thermal plume to the human *** fluctuation of capture efficiency in this condition was moderate relative to that for the human walking pattern beside the *** research could provide a comprehensive overview of different human walking patterns and their impact on residential kitchens and thereby facilitate the maintenance of kitchen air quality.

关键词： human walking overset mesh method dynamic simulation flow characteristics residential kitchen

Quasi-Phase Equilibrium Prediction of Multi-Element Alloys Based on Machine Learning and Deep Learning

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Computers, Materials & Continua 2023年第7期76卷 49-64页

作者： changsheng Zhu Borui Zhao Naranjo Villota Jose Luis Zihao gao Li Feng College of Computer and Communication Lanzhou University of TechnologyLanzhou730050China State Key Laboratory of Gansu Advanced Processing and Recycling of Non-Ferrous Metal Lanzhou University of TechnologyLanzhou730050China College of Materials Science and Engineering Lanzhou University of TechnologyLanzhou730050China

In this study,a phase field model is established to simulate the microstructure formation during the solidification of dendrites by taking the Al-Cu-Mg ternary alloy as an example,and machine learning and deep learning methods are combined with the Kim-Kim-Suzuki(KKS)phase field model to predict the quasi-phase *** paper first uses the least squares method to obtain the required data and then applies eight machine learning methods and five deep learning methods to train the quasi-phase equilibrium prediction *** obtaining different models,this paper compares the reliability of the established models by using the test data and uses two evaluation criteria to analyze the performance of these *** work find that the performance of the established deep learning models is generally better than that of the machine learning models,and the Multilayer Perceptron(MLP)based quasi-phase equilibrium prediction model achieves the best *** the Convolutional Neural Network(CNN)based model also achieves competitive *** experimental results show that the model proposed in this paper can predict the quasi-phase equilibrium of the KKS phase-field model accurately,which proves that it is feasible to combine machine learning and deep learning methods with phase-field model simulation.

关键词： Deep learning machine learning quasi-phase equilibrium material simulation

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土壤肥力实质的研究——Ⅰ.黑土

土壤学报 1984年第3期 229-237页

作者：陈恩凤周礼恺邱凤琼严昶升高子勤中国科学院林业土壤研究所

我国对于土壤肥力的研究有着悠久的历史,远在公元前约2200年写成的“禹贡”,约1120年写成的“周礼”和约767年写成的“管子”中,都有这方面的记载。值得提明的是我国农民在长期生产斗争中总结出:抗逆性强、宜种、宜肥、宜耕范围广的是肥... 详细信息

我国对于土壤肥力的研究有着悠久的历史,远在公元前约2200年写成的“禹贡”,约1120年写成的“周礼”和约767年写成的“管子”中,都有这方面的记载。值得提明的是我国农民在长期生产斗争中总结出:抗逆性强、宜种、宜肥、宜耕范围广的是肥土,反之是瘦土。他们强调了土壤本身的体质,而不单

关键词：土壤肥力复合体基础物质有机矿物陈恩凤结合态腐殖质草甸黑土微团聚体腐殖物质开垦年限胡敏素黑腐素

Pressure and flowrate distribution in central exhaust shaft with multiple randomly operating range hoods

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Building Simulation 2022年第1期15卷 149-165页

作者： Lingjie Zeng Leqi Tong Jun gao Bowen Du Chengquan Zhang Lipeng Lv changsheng Cao Xihui Ding College of Environmental Science and Engineering Tongji UniversityShanghai 200092China School of Mechanical Engineering Tongji UniversityShanghai 200092China Department of civil and mineral engineering University of TorontoTorontoCanada

Central flues are now commonly adopted in high-rise residential buildings in China for cooking oil fumes(COF)*** hoods of all floors are connected to the central shaft,where oil fumes were gathered and exhausted through the outlet at the building *** households may cook and use their range hood at random periods,there is great uncertainty of the amount of COF being *** addition,users can often adjust the exhaust rate of the range hood according to their *** a result,thousands of possible operating conditions consisting of distinct combinations of on/off conditions and fan speed occur randomly in the central COF exhaust system,causing the exhaust performance to vary considerably from condition to *** work developed a mathematical model for characterizing the operation of the central COF exhaust system in a high-rise residential building as well as its iterative solving ***-scale tests coupled with CFD simulation referring to a real 30-floor building were conducted to validate the proposed *** results show that the model agreed well with the CFD and experimental data under various system operating ***,the Monte-Carlo method was introduced to simulate the random operating characteristics of the system,and a hundred thousand cases corresponding to distinct system operating conditions were sampled and statistically analyzed.

关键词： central exhaust shaft building ventilation range hood high-rise residential building randomly operating Monte-Carlo simulation

Wave-ice dynamical interaction:a numerical model and its application

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Acta Oceanologica Sinica 2021年第11期40卷 129-137页

作者： Yang Zhang changsheng Chen Guoping gao Jianhua Qi Huichan Lin Wei Yu Liang Chang State Key Laboratory of Satellite Ocean Environment Dynamics Second Institute of OceanographyMinistry of Natural ResourcesHangzhou 310012China School for Marine Science and Technology University of Massachusetts-DartmouthNew Bedford MA 02744-1221USA College of Marine Ecology and Enviroment Shanghai Ocean UniversityShanghai 201306China College of Marine Sciences Shanghai Ocean UniversityShanghai 201306China

In this paper,an ice floe inner stress caused by the wave-induced bending moment is derived to estimate the stress failure of ice *** strain and stress failures are combined to establish a wave-induced ice yield *** added ice stress and strain failure module in the Finite-Volume Community Ocean Model(FVCOM),which already includes module of ice-induced wave *** a fully coupled wave-ice dynamical interaction model is established based on the ice and wave modules of *** model is applied to reproduce the ice and wave fields of the breakup events observed during the second Sea Ice Physics and Ecosystem Experiment(SIPEX-2)*** simulation results show that by adopting the combined wave-induced ice yield scheme,the model can successfully predict the ice breakup events,which the strain failure model is unable to *** comparing the critical significant wave height deduced from strain and stress failure schemes,it is concluded that the ice breakup is caused by the strain failure when wave periods are shorter than a threshold value,while the stress failure is the main reason for the ice breakup when wave periods are longer than the threshold *** either of these two ice-break inducement mechanisms could overestimate the ice floe size,and thus underestimate the velocity of the ice lateral melt and increase the error of simulation of polar ice extent.

关键词： wave-ice interaction FVCOM stress failure ice lateral melt

Reference satellite selection method for GNSS high-precision relative positioning

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Geodesy and Geodynamics 2017年第2期8卷 125-129页

作者： Xiao gao Wujiao Dai Zhiyong Song changsheng Cai School of Geosciences and Info-Physics Central South University Changsha 410083 China Northwest Electric Power Design Institute Co. Ltd. of China Power Engineering Consulting Group Xi'an 710032 China

Selecting the optimal reference satellite is an important component of high-precision relat/ve positioning because the reference satellite directly influences the strength of the normal equation. The reference satellite selection methods based on elevation and positional dilution of precision （PDOP） value were compared. Results show that all the above methods cannot select the optimal reference satellite. We introduce condition number of the design matrix in the reference satellite selection method to improve structure of the normal equation, because condition number can indicate the ill condition of the normal equation. The experimental results show that the new method can improve positioning accuracy and reliability in precise relative positioning.

关键词： Global Navigation Satellite System (GNSS)Relative positioning Reference satellite Positional dilution of precision (PDOP)Condition number

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泰山盘石散治疗滑胎的体会

光明中医 2003年第4期18卷 F002-F002页

作者：高长甡马海山东东阿县中医医院 252200

滑胎之名原出于,则谓数坠胎,即连续发生3次或以上流产者,多因气虚、脾虚、肾虚、血热、外伤等因素引起,以致如期而坠,该证现代医学称之为'习惯性流产',治疗颇为棘手,很多患者自妊娠之后,谨慎备至,也难免复坠之苦,我在临床工作中观察到... 详细信息

滑胎之名原出于,则谓数坠胎,即连续发生3次或以上流产者,多因气虚、脾虚、肾虚、血热、外伤等因素引起,以致如期而坠,该证现代医学称之为'习惯性流产',治疗颇为棘手,很多患者自妊娠之后,谨慎备至,也难免复坠之苦,我在临床工作中观察到泰山盘石散加减治疗脾肾气虚型滑胎疗效甚佳,今不揣浅陋将两则典型病例复录于下,供参考.

关键词：泰山盘石散中医药治疗滑胎习惯性流产健脾补肾固冲安胎

Using CONTAM to design ventilation strategy of negative pressure isolation ward considering different height of door gaps

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Energy and Built Environment 2024年第1期5卷 32-45页

作者： Mingyao Ma changsheng Cao Yukun Xu Zhijian Liu Lingjie Zeng Chengquan Zhang Jun gao School of Mechanical Engineering Tongji UniversityShanghai 200092China Department of Power Engineering North China Electric Power UniversityBaodingHebei 071003China College of Civil Engineering Tongji UniversityShanghai 200092China

Infectious disease departments in hospitals require pressure gradient to create unidirectional airflow to prevent the spread of contaminants,typically by creating active air infiltration through the difference between supply and exhaust air *** door gap is the channel of air flow between rooms,so its height has an important influence on the pressure difference and infiltration air volume of the *** is still a lack of research on setting reasonable ventilation strategies according to the different heights of door gaps at different positions in the *** this study,model of a set of isolation wards was established and analyzed using the multi-zone simulation software CONTAM,and the ventilation strategies with different heights of door gaps were applied to the actual infection diseases *** results show that in a building with ventilation system divided by functional area,the difference in the height of the door gaps requires different active infiltration air *** fluctuations in the medical and patient corridors are greater than in other *** significance of this study is to understand the active infiltration of air to guide the design and operation of ventilation systems in infectious disease hospitals or building remodeled to isolate close contacts of COVID-19 *** is also instructive for the design of pressure gradients in clean workshops,biological laboratories,and other similar buildings.

关键词： Door gap height Active infiltration Pressure gradient Multizone model CONTAM Control strategy