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Cosmological parameter estimation from large-scale structure deep learning

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Science China(Physics,Mechanics & Astronomy) 2020年第11期63卷 36-50页

作者： ShuYang Pan miaoxin liu Jaime Forero-Romero Cristiano G.Sabiu ZhiGang Li HaiTao Miao Xiao-Dong Li School of Physics and Astronomy Sun Yat-Sen UniversityGuangzhou 510297China Departamento de Física Universidad de los AndesBogotáCP 111711Colombia Department of Astronomy Yonsei UniversitySeoul 03722Korea College of Physics and Electronic Engineering Nanyang Normal UniversityNanyang 473061China

We propose a light-weight deep convolutional neural network(CNN)to estimate the cosmological parameters from simulated 3-dimensional dark matter distributions with high *** training set is based on 465 realizations of a cubic box with a side length of 256 h-1 Mpc,sampled with 1283 particles interpolated over a cubic grid of 1283 *** volumes have cosmological parameters varying within the flatΛCDM parameter space of 0.16≤?m≤0.46 and 2.0≤109 As≤*** neural network takes as an input cubes with 32^3 oxels and has three convolution layers,three dense layers,together with some batch normalization and pooling *** the final predictions from the network we find a 2.5%bias on the primordial amplitudeσ8 that cannot easily be resolved by continued *** correct this bias to obtain unprecedented accuracy in the cosmological parameter estimation with statistical uncertainties ofδ?m=0.0015 andδσ8=0.0029,which are several times better than the results of previous CNN *** with a 2-point analysis method using the clustering region of 0-130 and 10-130 h-1 Mpc,the CNN constraints are several times and an order of magnitude more precise,***,we conduct preliminary checks of the error-tolerance abilities of the neural network,and find that it exhibits robustness against smoothing,masking,random noise,global variation,rotation,reflection,and simulation *** effects are well understood in typical clustering analysis,but had not been tested before for the CNN *** work shows that CNN can be more promising than people expected in deriving tight cosmological constraints from the cosmic large scale structure.

关键词： large-scale structure of Universe cosmological parameters dark energy machine learning

Effect of surfactant frequently used in soil flushing on oxygen mass transfer in micro-nano-bubble aeration system

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Chinese Journal of Chemical Engineering 2024年第3期67卷 174-181页

作者： Mei Bai Zhibin liu Zhu liu Chenfei He Zhanhuang Fan miaoxin Yuan Jiangsu Key Laboratory of Urban Underground Engineering and Environmental Safety Southeast UniversityNanjing 211189China CECEP DADI(Hangzhou)Environmental Remediation Co. Ltd.Hangzhou 310020China

In-site soil flushing and aeration are the typical synergetic remediation technology for contaminated *** surfactant present in flushing solutions is bound to affect the aeration *** purpose of this study is to evaluate the effect of surfactant frequently used in soil flushing on the oxygen mass transfer in micro-nano-bubble(MNB)aeration ***,bio-surfactants and chemical surfactants were used to investigate their effects on Sauter mean diameter of bubble(dBS),gas holdup(ε),volumetric mass-transfer coefficient(kLa)and liquid-side mass-transfer coefficient(kL)in the MNB aeration ***,based upon the experimental results,the Sardeing's and Frossling's models were modified to describe the effect of surfactant on kL in the MNB *** results showed that,for the twenty aqueous surfactant solutions,with the increase in surfactant concentration,the value of dBS,kLa and kL decreased,while the value ofεand gas-liquid interfacial area(a)*** phenomena were mainly attributed to the synergistic effects of immobile bubble surface and the suppression of coalescence in the surfactant *** addition,with the presence of electric charge,MNBs in anionic surfactant solutions were smaller and higher in number than in non-ionic surfactant ***,the accumulation of surfactant on the gas-liquid interface was more conspicuous for small MNB,so the reduction of kL in anionic surfactant solutions was larger than that in non-ionic surfactant ***,the modified Frossling's model predicted the effect of surfactant on kL in MNB aeration system with reasonable accuracy.

关键词： Soil flushing Micro-nano-bubble aeration Bio-surfactant Mass transfer coefficient

平面内和偏心状态下钢板阻尼墙抗震性能对比研究

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建筑结构 2019年第4期49卷 103-106页

作者：刘淼鑫广东省建筑设计研究院广州510010

为研究钢板阻尼墙双向抗震性能,对2个设计参数相同的钢板阻尼墙在平面内和偏心状态下进行试验对比研究。提出采用非线性随动强化模型模拟钢板阻尼墙力学性能,模拟结果和试验结果很接近。通过试验与模拟结果对比研究可知,钢板阻尼墙在偏... 详细信息

为研究钢板阻尼墙双向抗震性能,对2个设计参数相同的钢板阻尼墙在平面内和偏心状态下进行试验对比研究。提出采用非线性随动强化模型模拟钢板阻尼墙力学性能,模拟结果和试验结果很接近。通过试验与模拟结果对比研究可知,钢板阻尼墙在偏心状态下依然有良好的抗震性能,故所提出的非线性随动强化模型模拟钢板阻尼墙力学性能是可行的。

关键词：钢板阻尼墙偏心状态非线性随动强化模型抗震性能

Aluminum and Activated Alumina Powder Additions on Microwave Synthesis of Al_(4)SiC_(4)

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China's Refractories 2024年第1期33卷 44-48页

作者： WANG Li liu Shijie WEI Haoyu MA Juanjuan DONG Binbin GENG Shangrui YAN miaoxin QIN Feng GUO Yusen Henan Key Laboratory of Green Building Materials Manufacturing and Intelligent Equipemnt Luoyang Institute of Science and TechnologyLuoyang 471023China

Aiming at improving the properties of magnesia carbon materials,silicon aluminum carbide(Al_(4)SiC_(4))containing materials were prepared using industrial aluminum powder,silicon carbide powder,and graphite as raw materials,and activated alumina powder as an additive,mixing thoroughly,pressing into cylinders and then firing at 1200℃for 30 min in a carbon embedded atmosphere by the microwave *** effects of the aluminum powder addition(20%and 24%,by mass)and activated alumina powder addition(0,3%,5%and 7%,by mass)on the microwave synthesis of Al_(4)SiC_(4) as well as the effect of the obtained Al_(4)SiC_(4) containing material on the properties of magnesia carbon bricks were *** results show that:compared with the samples with 20%aluminum powder,those with 24%aluminum powder generate more Al_(4)SiC_(4).With the activated alumina powder addition increasing from 0 to 7%,the amount of Al_(4)SiC_(4) generated increases first and then *** with the sample without activated alumina powder,the samples with activated alumina powder show lower bulk density and higher apparent *** the activated alumina powder addition increasing from 3%to 7%,the bulk density of the samples increases first and then decreases,while the apparent porosity of the samples shows an opposite *** optimal additions are 24%aluminum powder and 5%activated alumina powder,and Al_(4)SiC_(4) synthesized in this sample has a hexagonal plate *** the synthesized Al_(4)SiC_(4) containing material added,the magnesia carbon brick has slightly increased cold modulus of rupture,basically the same modulus of elasticity and improved oxidation resistance.

关键词： aluminum powder activated alumina powder microwave synthesis Al_(4)SiC_(4) magnesia carbon bricks

Microwave-assisted Synthesis of Al_(4)SiC_(4) and Its Effect on Properties of MgO-C Refractories

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China's Refractories 2024年第1期33卷 14-17页

作者： WANG Li liu Shijie WEI Haoyu GUO Yanyan GENG Shangrui YAN miaoxin QIN Feng GUO Yusen Ma Juanjuan DONG Binbin Henan Key Laboratory of Green Building Materials Manufacturing and Intelligent Equipemnt Luoyang Institute of Science and TechnologyLuoyang 471023China

Al_(4)SiC_(4) was synthesized from Al powder, silicon carbide, and graphite by microwave sintering, and characterized by XRD and SEM. Then the synthesized material was added to the magnesia carbon refractory brick to study its effect on the oxidation resistance, apparent porosity, bulk density, elastic modulus, and modulus of rupture. It is found that Al_(4)SiC_(4) can be synthesized by microwave sintering at 1 300 ℃ and the addition of Al_(4)SiC_(4)-containing material as an antioxidant can enhance the oxidation resistance of the magnesia carbon refractory brick.

关键词： microwave-assisted synthesis Al_(4)SiC_(4) MgO-C refractories oxidation resistance

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新型软钢阻尼墙的试验研究及性能分析

地震工程与工程振动 2013年第1期33卷 133-139页

作者：谭平刘淼鑫周福霖广州大学减震控制与结构安全国家重点实验室培育基地广东广州510405

本文提出的新型软钢阻尼墙是一种设计新颖、耗能能力很强的剪切型金属阻尼器。给出了该新型软钢阻尼墙试件的构造形式。基于提出的加载方案对试件分别进行了基本性能试验和疲劳性能试验,分析了试件的滞回性能与疲劳性能等。试验结果表... 详细信息

本文提出的新型软钢阻尼墙是一种设计新颖、耗能能力很强的剪切型金属阻尼器。给出了该新型软钢阻尼墙试件的构造形式。基于提出的加载方案对试件分别进行了基本性能试验和疲劳性能试验,分析了试件的滞回性能与疲劳性能等。试验结果表明该新型软钢阻尼墙具有稳定、良好的滞回性能和疲劳性能。采用ABAQUS软件对其建立了精细化有限元模型,并对其进行了有限元分析。数值仿真结果与试验结果很接近。这种新型软钢阻尼墙耗能性能优越,构造简单,且施工方便,有广阔的工程应用前景。

关键词：软钢阻尼墙消能减震低周反复试验有限元分析

基于GIS与平台模拟水库大坝的灾害应急响应研究

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水利建设与管理 2019年第8期39卷 76-79,63页

作者：刘淼新梅州市大埔县移民工作局

借助GIS、Terra Vista和MultiGen Creator平台,可实现高精度大坝、库区和洪水的数字化处理;利用数字高程模拟(DEM)技术模拟洪水演变进程,可分析洪水淹没过程和可能受灾的区域;利用GIS地理信息并结合物资储备情况、受灾区域交通状况以及... 详细信息

借助GIS、Terra Vista和MultiGen Creator平台,可实现高精度大坝、库区和洪水的数字化处理;利用数字高程模拟(DEM)技术模拟洪水演变进程,可分析洪水淹没过程和可能受灾的区域;利用GIS地理信息并结合物资储备情况、受灾区域交通状况以及可能的避难路径,可求解最佳的撤离路径。GIS与平台模拟相结合可为大坝灾害应对与决策提供科学的分析方法。

关键词：数字化水库大坝灾害模拟

基于极限分析上限理论的韩江大麻防护工程边坡稳定性分析

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水利技术监督 2019年第5期27卷 191-193,266页

作者：刘淼新梅州市大埔县移民工作局广东梅州514299

文章建立了基于极限分析上限理论的膨胀土边坡裂缝效应稳定性分析方法,并探讨了裂隙深度和裂缝角度对膨胀土边坡稳定性的影响。结果表明:安全系数随裂缝深度的增加而减小,在考虑地震作用和变形力的影响下,安全系数最小。裂缝角度对边坡... 详细信息

文章建立了基于极限分析上限理论的膨胀土边坡裂缝效应稳定性分析方法,并探讨了裂隙深度和裂缝角度对膨胀土边坡稳定性的影响。结果表明:安全系数随裂缝深度的增加而减小,在考虑地震作用和变形力的影响下,安全系数最小。裂缝角度对边坡安全系数的影响不显著。当裂缝角度大于70°时,安全系数变小。与裂缝角相比,裂缝深度对边坡安全系数影响较大。

关键词：极限理论防护工程边坡稳定性应用

钢板阻尼墙基于Bouc-Wen模型的模拟和工程应用研究

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华南地震 2019年第1期39卷 46-49页

作者：刘淼鑫广东省建筑设计研究院广州510010

钢板阻尼墙抗震性能好,设计自由度大,在工程中使用越来越多。为了更高精度地模拟钢板阻尼墙的力学性能,提出基于Bouc-Wen模型的模拟分析方法。给出一种基于Bouc-Wen模型钢板阻尼墙参数辨识方法,根据试验数据和仿真结果的验证对比,文中... 详细信息

钢板阻尼墙抗震性能好,设计自由度大,在工程中使用越来越多。为了更高精度地模拟钢板阻尼墙的力学性能,提出基于Bouc-Wen模型的模拟分析方法。给出一种基于Bouc-Wen模型钢板阻尼墙参数辨识方法,根据试验数据和仿真结果的验证对比,文中提出的模拟方法可以较好地反映钢板阻尼墙的的力学性能曲线。该模拟方法可得到较好的仿真效果,对实际工程设计分析钢板阻尼墙对结构的抗震性能影响有高精度、数据化的帮助,可为进一步工程应用和设计分析提供参考。

关键词：钢板阻尼墙 Bouc-Wen模型参数辨识工程应用