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波形钢腹板-钢底板组合箱梁耐火极限与设计

铁道工程学报 2024年第9期41卷 30-35页

作者：程海根沈强郑尚敏管冲华东交通大学南昌330013 重庆大学重庆400044

研究目的:近年来交通量的增加,由车辆碰撞或易燃物品运输车辆引起的桥梁火灾时有发生,不容忽视。为了解火灾下波形钢腹板-钢底板组合箱梁的火灾响应,采用ANSYS建立三维热-力耦合分析模型,分析火灾下组合箱梁温度场分布状态与抗弯承载力... 详细信息

研究目的:近年来交通量的增加,由车辆碰撞或易燃物品运输车辆引起的桥梁火灾时有发生,不容忽视。为了解火灾下波形钢腹板-钢底板组合箱梁的火灾响应,采用ANSYS建立三维热-力耦合分析模型,分析火灾下组合箱梁温度场分布状态与抗弯承载力衰变规律,研究不同受火场景对组合箱梁耐火极限的影响,提出抗火设计方法。研究结论:(1)火灾下组合箱梁截面抗弯承载力呈三阶段发展;不同受火范围下跨中挠度随受火时间延长均呈两阶段发展;随着受火长度的增加,组合箱梁挠度增长幅度越大,受火初期受热弯曲效应作用越显著;(2)与抗力准则相比,采用挠度破坏准则判定组合箱梁的耐火极限较安全;(3)在组合箱梁底板增设不同类型的加劲肋形式,均可提高组合箱梁的耐火极限,当加劲肋材料用量相同时,与增设通长加劲肋相比,增设底板局部加劲肋对组合箱梁的耐火极限改善效果更好;(4)本研究成果可为波形钢腹板-钢底板组合箱梁的耐火极限理论分析与抗火设计提供参考。

关键词：桥梁工程耐火极限抗火设计波形钢腹板组合箱梁

比率低频振幅技术在延年九转法治疗慢性疲劳综合征伴焦虑抑郁中的应用价值

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磁共振成像 2024年第7期15卷 58-63页

作者：谢芳芳顾元嘉管翀谢超群许家佗姚斐上海中医药大学针灸推拿学院上海201203 上海中医药大学中医学院上海201203

目的比较延年九转法与认知行为治疗后,慢性疲劳综合征(chronic fatigue syndrome,CFS)伴焦虑与抑郁症状患者的大脑静息态下功能MRI(functional MRI,fMRI)比率低频振幅(fractional amplitude of low-frequency fluctuations,fALFF)的脑区差异改变情况。材料与方法将30例CFS患者随机分为延年九转法组和认知行为组,治疗12周后进行fMRI检测,采用Pearson相关分析探索fALFF变化与焦虑抑郁量表(Hospital Anxiety and Depression Scale,HADS)的线性相关性。结果与认知行为组相比,延年九转法组fALFF减弱的脑区有左侧梭状回、左侧枕上回、左侧角回;增强的脑区有右侧颞中回。焦虑症状分值与梭状回(r=0.525,P=0.044)和枕上回(r=0.559,P=0.030)的fALFF平均值呈正相关,抑郁症状分值与梭状回(r=0.542,P=0.037)的fALFF平均值呈正相关(P<0.05)。结论延年九转法可能通过梭状回、枕上回、角回、颞中回神经活动水平强弱客观反映CFS患者焦虑与抑郁症状。

关键词：慢性疲劳综合征焦虑抑郁延年九转法气功静息态功能磁共振成像磁共振成像比率低频振幅神经元活动

Early Miocene Paleoaltitude of the Tuotuohe Basin,Central-Northern Tibetan Plateau and its Tectonic Implications

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Acta Geologica Sinica(English Edition) 2020年第5期94卷 1364-1372页

作者： LI Leyi CHANG Hong guan chong LIU Weiguo CAO Yunning State Key Laboratory of Loess and Quaternary Geology Institute of Earth EnvironmentChinese Academy of SciencesXi'an 710061China University of Chinese Academy of Sciences Beijing 100049China Xi’an Institute for Innovative Earth Environment Research Xi’an 710061China CAS Center for Excellence in Quaternary Science and Global Change Xi’an 710061China Institute of Tibetan Plateau Research Chinese Academy of SciencesBeijing 100101China

Reconstruction of the paleoaltitude history of the Tibetan Plateau is critical for understanding the linkage between tectonics and its effect on regional and global climate ***,most of the paleoaltitude studies are concentrated on the southern and southeastern part of the Tibetan Plateau,and few studies have been conducted in the central-northern *** this paper we focused on the Wudaoliang Formation in the Tuotuohe Basin,central to northern Tibetan Plateau,to reconstruct paleoaltitude based on carbonate oxygen *** carbonate samples are primary or have experienced an early stage of *** on the thermodynamic and empirical model results,the paleoaltitude of the Wudaoliang Formation is found to be around 2700–3260 m(average of 2980±280 m)in the early Miocene(~24 Ma).Integrating paleoaltitude results from Wudaoliang Basin and our results,we conclude that crustal shortening and tectonic activity were strong during the late Eocene to late Oligocene-early Miocene and relatively weak during the early Miocene in the central-northern Tibetan Plateau.

关键词： paleoaltitude oxygen isotope crustal shortening Wudaoliang Formation Tuotuohe Basin Tibetan Plateau

Artificial intelligence innovation in education: A twenty-year data-driven historical analysis

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International Journal of Innovation Studies 2020年第4期4卷 134-147页

作者： chong guan Jian Mou Zhiying Jiang School of Business Singapore University of Social Sciences(SUSS)Singapore School of Business Pusan National UniversityBusan46241South Korea

Reflecting on twenty years of educational research,we retrieved over 400 research article on the application of artificial intelligence(AI)and deep learning(DL)techniques in teaching and learning.A computerised content analysis was conducted to examine how AI and DL research themes have evolved in major educational *** doing so,we seek to uncover the prominent keywords associated with AI-enabled pedagogical adaptation research in each decade,due to the discipline’s *** examining the major research themes and historical trends from 2000 to 2019,we demonstrate that,as advanced technologies in education evolve over time,some areas of research topics seem have stood the test of time,while some others have experienced peaks and *** importantly,our analysis highlights the paradigm shifts and emergent trends that are gaining prominence in the field of educational *** instance,the results suggest the decline in conventional tech-enabled instructional design research and the flourishing of student profiling models and learning ***,this paper serves to raise awareness on the opportunities and challenges behind AI and DL for pedagogical adaptation and initiate a dialogue.

关键词： Artificial intelligence Systematic review Intelligent tutoring systems Virtual reality Educational data mining

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《诸病源候论》脾胃病导引法探析

天津中医药大学学报 2024年第3期43卷 272-276页

作者：顾元嘉管翀谢芳芳姚斐上海中医药大学针灸推拿学院上海201203 上海中医药大学附属上海市中医医院上海200071

《诸病源候论》是中国现存最早病因病机证候学专著,书中记载大量脾胃病相关症状并提供导引治疗方法。其导引方法涉及调身、调息、调心3个方面,且各有侧重。文章从功法三调角度,总结分析《诸病源候论》脾胃病导引治疗规律,发现《诸病源... 详细信息

《诸病源候论》是中国现存最早病因病机证候学专著,书中记载大量脾胃病相关症状并提供导引治疗方法。其导引方法涉及调身、调息、调心3个方面,且各有侧重。文章从功法三调角度,总结分析《诸病源候论》脾胃病导引治疗规律,发现《诸病源候论》导引治疗脾胃病时注重调畅气机,主要包括“以脊为枢”调畅气机出入,“闭气调息”调节气机升降,并注重“以意引气”增强调身及调息的效果。

关键词：诸病源候论脾胃导引辨证论治

On Homomorphism of Valuation Algebras

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Communications in Mathematical Research 2011年第1期27卷 69-80页

作者： guan XUE-chong LI YONG-MING College of Mathematics and Information Science Shaanxi Normal University Xi ＇an 710062 School of Mathematical Science Xuzhou Normal University Xuzhou Jiangsu 221116 College of Computer Science Shaanxi Normal University Xi＇an 710062

In this paper, firstly, a necessary condition and a sufficient condition for an isomorphism between two semiring-induced valuation algebras to exist are presented respectively. Then a general valuation homomorphism ba... 详细信息

关键词： homomorphism valuation algebra semiring

Building stock market resilience through digital transformation:Using Google trends to analyze the impact of COVID-19 pandemic

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Frontiers of Business Research in China 2020年第3期14卷 257-277页

作者： Ding Ding chong guan Calvin MLChan Wenting Liu School of Business Singapore University of Social Sciences463 Clementi RdSingapore 599494Singapore

As the 2019 novel coronavirus disease(COVID-19)pandemic rages globally,its impact has been felt in the stock markets around the *** the gloomy economic outlook,certain sectors seem to have survived better than *** paper aims to investigate the sectors that have performed better even as market sentiment is affected by the *** daily closing stock prices of a total usable sample of 1,567 firms from 37 sectors are first an a lyzed using a combination of hierarchical clustering and shape-based distance(SBD)*** sentiment is modeled from Google trends on the COVID-19 *** is then analyzed against the time series of daily closing stock prices using augmented vector autoregression(VAR).The empirical results indicate that market sentiment towards the pandemic has significant effects on the stock prices of the ***,the stock price performance across sectors is differentiated by the level of the digital transformation of sectors,with those that are most digitally transformed,showing resili ence towards negative market sentime nt on the *** study contributes to the existing literature by incorporating search trends to an a lyze market sentiment,and by showing that digital transformation moderated the stock market resilience of firms against concern over the COVID-19 outbreak.

关键词： Digital transformation Stock market Search trends Market sentiment 2019 novel coronavirus disease(COVID-19)

The Ellerman bomb and ultraviolet burst triggered successively by an emerging magnetic flux rope

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Research in Astronomy and Astrophysics 2021年第9期21卷 163-179页

作者： guan-chong Cheng Lei Ni Ya-Jie Chen Udo Ziegler Jun Lin Yunnan Observatories Chinese Academy of SciencesKunming 650216China University of Chinese Academy of Sciences Beijing 100049China CAS Key Laboratory of Solar Activity National Astronomical ObservatoriesBeijing 100101China Center for Astronomical Mega-Science Chinese Academy of SciencesBeijing 100101China School of Earth and Space Sciences Peking UniversityBeijing 100871China Astrophysikalisches Institut Potsdam D-14482 Potsdam Germany

Ellerman bombs(EBs)and ultraviolet(UV)bursts are common brightening phenomena,which are usually generated in the low solar atmosphere of emerging flux *** this paper,we have investigated the emergence of an initial un-twisted magnetic flux rope based on three-dimensional(3 D)magneto-hydrodynamic(MHD)*** EB-like and UV burst-like activities successively appear in the U-shaped part of the undulating magnetic fields triggered by the Parker *** EB-like activity starts to appear earlier and lasts for about 80 *** minutes later,a much hotter UV burstlike event starts to appear and lasts for about 60 *** the direction vertical to the solar surface,both the EB and UV burst start in the low chromosphere,but the UV burst extends to a higher altitude in the up *** regions with apparent temperature increase in the EB and UV burst are both located inside the small twisted flux ropes generated in magnetic reconnection processes,which are consistent with the previous 2 D simulations that most hot regions are usually located inside the magnetic ***,the twisted flux rope corresponding to the EB is only strongly heated after it floats up to an altitude much higher than the reconnection site during that *** analyses show that the EB is heated by the shocks driven by the strong horizontal flows at two sides of the U-shaped magnetic *** twisted flux rope corresponding to the UV burst is heated by the driven magnetic reconnection process.

关键词： magnetic reconnection (magnetohydrodynamics)MHD shocks Sun:heating Sun:low solar atmosphere Sun:magnetic flux emergence

Association between physical activity and digestive-system cancer: An updated systematic review and meta-analysis

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Journal of Sport and Health Science 2021年第1期10卷 4-13页

作者： Fangfang Xie Yanli You Jihan Huang chong guan Ziji Chen Min Fang Fei Yao Jia Han School of Acupuncture-Moxibustion and Tuina Shanghai University of Traditional Chinese MedicineShanghai 201203China Department of Traditional Chinese Medicine Changhai HospitalNaval Medical UniversityShanghai 200433China Center for Drug Clinical Research Shanghai University of Traditional Chinese MedicineShanghai 201203China Department of Physiotherapy and Sport Rehabilitation Shanghai University of SportShanghai 200438China

Background:Physical activity(PA)may have an impact on digestive-system cancer(DSC)by improving insulin sensitivity and anticancer immune function and by reducing the exposure of the digestive tract to carcinogens by stimulating gastrointestinal motility,thus reducing transit *** current study aimed to determine the effect of PA on different types of DSC via a systematic review and ***:In accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses(PRISMA)guidelines,we searched for relevant studies in PubMed,Embase,Web of Science,Cochrane Library,and China National Knowledge *** a random effects model,the relationship between PA and different types of DSC was ***:The data used for meta-analysis were derived from 161 risk estimates in 47 studies involving 5,797,768 participants and 55,162 *** assessed the pooled associations between high *** PA levels and the risk of DSC(risk ratio(RR)=0.82,95%confidence interval(95%CI):0.79-0.85),colon cancer(RR=0.81,95%CI:0.76-0.87),rectal cancer(RR=0.88,95%CI:0.80-0.98),colorectal cancer(RR=0.77,95%CI:0.69-0.85),gallbladder cancer(RR=0.79,95%CI:0.64-0.98),gastric cancer(RR=0.83,95%CI:0.76-0.91),liver cancer(RR=0.73,0.60-0.89),oropharyngeal cancer(RR=0.79,95%CI:0.72-0.87),and pancreatic cancer(RR=0.85,95%CI:0.78-0.93).The findings were comparable between case-control studies(RR=0.73,95%CI:0.68-0.78)and prospective cohort studies(RR=0.88,95%CI:0.80-0.91).The meta-analysis of 9 studies reporting low,moderate,and high PA levels,with 17 risk estimates,showed that compared to low PA,moderate PA may also reduce the risk of DSC(RR=0.89,95%CI:0.80-1.00),while compared to moderate PA,high PA seemed to slightly increase the risk of DSC,although the results were not statistically significant(RR=1.11,95%CI:0.94-1.32).In addition,limited evidence from 5 studies suggested that meeting the international PA guidelines might not significantly reduce the risk of DS

关键词： Digestive-system cancer Meta-analysis Physical activity