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高新区丰达桥服役期可靠性评价分析

黑龙江交通科技 2024年第2期47卷 69-73页

作者：崔宇鹏中国公路工程咨询集团路桥设计研究院分公司湖北武汉430040

为了对桥梁正常服役期做出可靠性评价,保证桥梁结构后续使用过程中安全,稳固,耐久,对高新区辖区丰达桥进行了静载试验和动载试验。在静载试验过程中,通过测定试验荷载作用下的桥梁控制截面应力以及挠度,与理论值对比评价实际结构使用性... 详细信息

为了对桥梁正常服役期做出可靠性评价,保证桥梁结构后续使用过程中安全,稳固,耐久,对高新区辖区丰达桥进行了静载试验和动载试验。在静载试验过程中,通过测定试验荷载作用下的桥梁控制截面应力以及挠度,与理论值对比评价实际结构使用性能和工作状态。桥梁结构的自振特性和动力响应是通过动载试验来测定的,并对实际结构的动力表现进行评价。通过综合试验结果评价桥梁的实际承载力,为桥梁后续工作提供原始数据资料。在试验荷载作用下,丰达桥2#跨和3#跨主测截面的应变和挠度校验系数均小于1.0,结构动力性能良好,丰达桥2#跨和3#跨的承载能力满足《城市桥梁设计荷载标准》(CJJ 77—98)规定的汽车荷载(城-A级)正常使用要求。按照《城市桥梁养护技术标准》(CJJ 99—2017)的要求,对丰达桥进行日常养护管理工作即可。

关键词：丰达桥可靠性静载试验动载试验外观检查

数字鸿沟与老年人身心健康:文化资本的中介作用

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人口与发展 2024年第5期30卷 38-47页

作者：崔钰鹏何有世周绿林许兴龙江苏大学管理学院江苏镇江212013

老年人作为“数字弱势群体”与互联网时代发展要求互为矛盾,在老龄化社会的背景下,数字鸿沟对老年人身心健康造成的影响亟待关注。研究基于2020年中国家庭追踪调查(CFPS)数据,采用回归分析法检验数字鸿沟对老年人身心健康的影响效应,以... 详细信息

老年人作为“数字弱势群体”与互联网时代发展要求互为矛盾,在老龄化社会的背景下,数字鸿沟对老年人身心健康造成的影响亟待关注。研究基于2020年中国家庭追踪调查(CFPS)数据,采用回归分析法检验数字鸿沟对老年人身心健康的影响效应,以逐步回归检验法和Bootstrap法检验文化资本的中介效应。研究发现数字鸿沟对老年人身心健康的影响起负向作用,对老年人的身体健康和记忆健康影响较大,且其影响效应具有城乡异质性特征。老年人面临的数字鸿沟问题越小,身心健康水平越高。文化资本在数字鸿沟影响老年人身心健康的过程中具有中介效应,数字鸿沟对老年人身心健康的抑制作用可以通过文化资本水平的提高得到缓解。上述结论均通过稳健性检验。研究结论可为弥合老年人数字鸿沟问题、提高老年人身心健康水平提供参考意见。

关键词：数字鸿沟文化资本老年人身心健康

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协作学习模式在工程制图课程教学中的应用

模具制造 2024年第7期24卷 105-107页

作者：崔宇鹏郭可栋安阳工学院河南安阳455000

工程制图课程是工科专业的基础课,具有较强的理论性和实践性,需要学生构建空间思维。传统教学模式已经不能激发学生主动学习的热情,不适应高等教育的发展要求,而协作学习模式是强调“以学生为中心”理念的教学方法,注重培养学生学习能... 详细信息

工程制图课程是工科专业的基础课,具有较强的理论性和实践性,需要学生构建空间思维。传统教学模式已经不能激发学生主动学习的热情,不适应高等教育的发展要求,而协作学习模式是强调“以学生为中心”理念的教学方法,注重培养学生学习能力。从课程教学、专业实践、创新活动3个方面分析了以协作学习模式为主的混合教学模式,讨论了小组协作学习模式的考核评价方法,实践反馈了协作学习模式的优越性,可为提高高校教学质量提供参考和借鉴。

关键词：协作学习工程制图主动学习教学应用

One-bit compressed sensing recovery algorithm robust to perturbation

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The Journal of China Universities of Posts and Telecommunications 2018年第1期25卷 62-69页

作者： cui yupeng Xu Wenbo Lin Jiaru Key Laboratory of Universal Wireless Communication Beijing University of Posts and Telecommunications

One-bit compressed sensing （CS） technology reconstructs the sparse signal when the available measurements are reduced to only their sign-bit. It is well known that CS reconstruction should know the measurement matrix exactly to obtain a correct result. However, the measurement matrix is probably perturbed in many practical scenarios. An iterative algorithm called perturbed binary iterative hard thresholding （PBIHT） is proposed to reconstruct the sparse signal from the binary measurements （sign measurements） where the measurement matrix experiences a general perturbation. The proposed algorithm can reconstruct the original data without any prior knowledge about the perturbation. Specifically, using the ideas of the gradient descent, PBIHT iteratively estimates signal and perturbation until the estimation converges. Simulation results demonstrate that, under certain conditions, PBIHT improves the performance of signal reconstruction in the perturbation scenario.

关键词： one-bit compressed sensing reconstruction algorlthm perturbation robust

冰水赋存演化下冻结土石混合体-结构界面强度劣化机制及模型

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岩土工程学报 2024年第5期46卷 988-997页

作者：唐丽云王鹏宇郑娟娟于永堂金龙崔玉鹏罗滔西安科技大学建筑与土木工程工程学院陕西西安710054 中联西北工程设计研究院有限公司陕西西安710077 中交第一公路勘察设计研究院有限公司陕西西安710004 西京学院陕西省混凝土结构安全与耐久性重点实验室陕西西安710123

温升下冻结土石混合体-结构界面层孔隙内冰水赋存改变极易诱发强度劣化,而目前界面强度劣化机制及劣化规律定量表征的相关研究存在空白。制备0%,15%,30%,45%等4种含石率组合体试样,通过核磁共振、直剪试验研究了正融过程冰水赋存演化下... 详细信息

温升下冻结土石混合体-结构界面层孔隙内冰水赋存改变极易诱发强度劣化,而目前界面强度劣化机制及劣化规律定量表征的相关研究存在空白。制备0%,15%,30%,45%等4种含石率组合体试样,通过核磁共振、直剪试验研究了正融过程冰水赋存演化下界面强度劣化特性,结合莫尔-库仑准则首次提出以薄膜水及毛细水含量变化率为参变量的强度劣化模型。得到结论:含石改变界面孔隙结构分布使毛细水占比升高;温升下界面抗剪强度劣化程度随含石率增加而降低;正融后不同含石率界面黏聚力衰减程度均大于内摩擦角衰减程度;黏聚力、内摩擦角与未冻水含量关系曲线分别呈阶段非线性特点及两阶段线性特点,其实质在于薄膜水及毛细水发育使得界面黏聚力和内摩擦角产生不同程度及形式的劣化。模型分析表明:随含石率升高,薄膜水及毛细水劣化系数具有“此消彼长”的特性,颗粒间及颗粒与结构接触面滑动摩擦强度和咬合摩擦强度劣化比例系数分别呈现下降、上升趋势。

关键词：正融土石混合体-结构界面冰水赋存强度劣化模型

Large eddy simulation of stably stratified turbulence

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Science China(Physics,Mechanics & Astronomy) 2010年第1期53卷 135-146页

作者： SHEN Zhi, LI yupeng, cui GuiXiang & ZHANG ZhaoShun Department of Engineering Mechanics, Tsinghua University, Beijing 100084, China 1. Department of Engineering Mechanics Tsinghua University Beijing 100084 China

Stable stratification turbulence, as a common phenomenon in atmospheric and oceanic flows, is an important mechanism for numerical prediction of such flows. In this paper the large eddy simulation is utilized for investigating stable stratification turbulence numerically. The paper is expected to provide correct statistical results in agreement with those measured in the atmosphere or ocean. The fully developed turbulence is obtained in the stable stratification fluid by large eddy simulation with different initial velocity field and characteristic parameters, i.e. Reynolds number Re and Froude number Fr. The evolution of turbulent kinetic energy, characteristic length scales and parameters is analyzed for investigating the development of turbulence in stable stratification fluid. The three-dimensional energy spectra, horizontal and vertical energy spectrum, are compared between numerical simulation and real observation in the atmosphere and ocean in order to test the reliability of the numerical simulation. The results of numerical cases show that the large eddy simulation is capable of predicting the properties of stable stratification turbulence in consistence with real measurements at less computational cost. It has been found in this paper that the turbulence can be developed under different initial velocity conditions and the internal wave energy is dominant in the developed stable stratification turbulence. It is also found that the characteristic parameters must satisfy certain conditions in order to have correct statistical property of stable stratification turbulence in the atmosphere and ocean. The Reynolds number and Froude number are unnecessarily equal to those in atmosphere or ocean, but the Reynolds number must be large enough, say, greater than 10 2 , and Froude number must be less than 0.1. The most important parameter is ReFr 2 which must be greater than 10.

关键词： stratified turbulence internal wave potential vortex large eddy simulation

QTL and genetic analysis controlling fiber quality traits using paternal backcross population in upland cotton

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Journal of Cotton Research 2020年第3期3卷 156-166页

作者： MA LingLing SU Ying NIE Hushuai cui yupeng CHENG Cheng IJAZ Babar HUA Jinping Laboratory of Cotton Genetics Genomics and Breeding/Beijing Key Laboratory of Crop Genetic Improvement/Key Laboratory of Crop Heterosis and Utilization of Ministry of EducationCollege of Agronomy and BiotechnologyChina Agricultural UniversityBeijing 100193China

Background:Genetic improvement in fiber quality is one of the main challenges for cotton *** trait loci(QTL)mapping provides a powerful approach to dissect the molecular mechanism in fiber quality *** present study,F14 recombinant inbred line(RIL)population was backcrossed to paternal parent for a paternal backcross(BC/P)population,deriving from one upland cotton *** repetitive BC/P field trials and one maternal backcross(BC/M)field trial were performed including both two BC populations and the original RIL ***:In total,24 novel QTLs are detected for fiber quality traits and among which 13 QTLs validated previous ***-five QTLs in BC/P populations explain 5.01%–22.09%of phenotype variation(PV).Among the 35 QTLs,23 QTLs are detected in BC/P population *** study provides novel alleles of male parent for fiber quality traits with positive genetic ***,qFS-Chr3–1 explains 22.09%of PV in BC/P population,which increaseds 0.48 cN·tex−1 for fiber strength.A total of 7,2,8,2 and 6 QTLs explain over 10.00%of PV for fiber length,fiber uniformity,fiber strength,fiber elongation and fiber micronaire,*** RIL population,six common QTLs are detected in more than one environment:qFL-Chr1–2,qFS-Chr5–1,qFS-Chr9–1,qFS-Chr21–1,qFM-Chr9–1 and qFM-Chr9–*** common QTLs of qFE-Chr2–2(TMB2386-SWU12343)and qFM-Chr9–1(NAU2873-CGR6771)explain 22.42%and 21.91%of *** region between NAU4034 and TMB1296 harbor 30 genes(379 kb)in A05 and 42 genes(49 kb)in D05 for fiber length along the QTL qFL-Chr5–1 in BC/P population,*** addition,a total of 142 and 46 epistatic QTLs and QTL×environments(E-QTLs and QQEs)are identified in recombinant inbred lines in paternal backcross(RIL-P)and paternal backcross(BC/P)populations,***:The present studies provide informative basis for improving cotton fiber quality in different populations.

关键词： Fiber quality traits Common QTL Paternal backcross population Upland cotton

A targeted QTL analysis for fiber length using a genetic population between two introgressed backcrossed inbred lines in upland cotton(Gossypium hirsutum)

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The Crop Journal 2019年第3期7卷 273-282页

作者： Guoyuan Liua Wenfeng Pei Dan Li Jianjiang Ma yupeng cui Nuohan Wang Jikun Song Man Wu Libei Li Xinshan Zang Shuxun Yu Jinfa Zhang Jiwen Yu State Key Laboratory of Cotton Biology Cotton Institute of the Chinese Academy of Agricultural SciencesKey Laboratory of Cotton Genetic ImprovementMinistry of AgricultureAnyang 455000HenanChina Xinjiang Research Base State Key Laboratory of Cotton BiologyXinjiang Agricultural UniversityUrumqi 830001XinjiangChina Department of Plant and Environmental Sciences New Mexico State UniversityLas CrucesNM 88003USA

Cotton fiber is the most important natural raw material for the textile industry, and fiber length(FL) is one of the most important traits in *** trait locus(QTL)mapping based on high-density genetic maps is an efficient approach to identify genetic regions for *** our study, two backcrossed inbred lines(BILs) were chosen as parents to construct a high-density genetic map in F2 which was used to fine map FL QTL in F2:3 *** genetic map had a total size of 3462.8 cM, containing 9182 singlenucleotide polymorphisms(SNPs) based on *** FL related stable QTL were identified on two chromosomes(qFL-A08–1 on A08 and qFL-D03–1 on D03),and qFL-A08–1 was confirmed by a *** previously obtained RNA-seq data for the two BILs and qRT-PCR analysis, two candidate genes annotated as cytochrome b5(CB5, Gh_A08 G1729) and microtubule end-binding 1 C(EB1C, Gh_D03 G0232) that may regulate FL during the fiber elongation stage were *** addition, nine recombination hotspots in this population were *** results of this study will provide an important foundation for further studies on the molecular and genetic regulation of fiber elongation.

关键词： Gossypium Single-nucleotide polymorphism Fiber length Quantitative trait locus

Distribution and dynamics of niche and interspecific association of dominant phytoplankton species in the Feiyun River basin,Zhejiang,China

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Journal of Oceanology and Limnology 2024年第4期42卷 1157-1172页

作者： Shengnan ZHU Zengchuan DONG Guobin FU Shujun WU Jinyu MENG Weilin LIU yupeng LIU Xun cui Yuejiao ZHOU College of Hydrology and Water Resources Hohai UniversityNanjing 210098China CSIRO Environment Private Bag 5Wembley WA 6913Australia Department of Agricultural and Biological Engineering Indian River Research and Education CenterUniversity of FloridaFort Pierce 34945USA Jiangxi Provincial Key Laboratory of Hydrology-Water Resources and Water Environment Nanchang Institute of TechnologyNanchang 330099China

To investigate the dominant species and interspecific association in the phytoplankton community of the Feiyun River basin in Zhejiang Province,East China,the main stream and the Shanxi Zhaoshandu Reservoir in the downstream were chosen as the study area,for which 22 sampling sites were *** was conducted in September 2021,January,May,and July *** species were identified from both quantitative samples and in-vivo *** was quantified by direct *** show that there were 98 species belonging to 6 phyla and 78 *** addition,to clarify the niches of the dominant phytoplankton species and their interspecific association,the dominance index was calculated,and a comprehensive analysis was conducted including niche width,niche overlap value,ecological response rate,overall association,chi-square test,and the *** phytoplankton community exhibited characteristics of a Cyanobacteria-Chlorophyta-Diatom type community,showing higher diversity in spring and lower diversity in *** 11 dominants phytoplankton species from 3 phyla,both frequency and dominance degree varied seasonally,of which Microcystis *** the dominant species in Spring,Autumn,and *** niche widths of the dominant species ranged from 0.234 to 0.933,and were categorized into three *** niche overlap values of the 11 dominant species ranged from 0.359 to 0.959,exhibiting significant seasonal differences-highest in winter followed by autumn,spring,and summer in *** overall correlation among dominant species in all four seasons revealed a non-significant negative association,resulting in an unstable community structure.A significant portion(84.2%)of species pairs displayed positive associations,suggesting a successional pattern where Diatoms dominated while other dominant species shared resources and *** this pattern,stability measurements indicated that the dominant species community remained unstable.T

关键词： phytoplankton dominant species niche interspecific association Feiyun River basin