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Finite Element Analysis on Vibration Characteristics of an Offshore Floating Breakwater

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Structural Durability & Health Monitoring 2020年第1期14卷 19-36页

作者： hongyi yan Dingguo Zhang Liang Li Xiaoyu Luo Nanjing University of Science and Technology Nanjing210094China Electric Power Research Institute of Guangdong Power Grid Co LtdGuangzhou510080China

The construction of seaside facilities is a hot topic in the field of ocean engineering.In this paper,a new type of floating breakwater is designed by 3D-CAD geometric modeling.Based on the vibration theory and finite element tech-nology,the floating breakwater model is optimized,and the modal analysis of the structure with the bracket as main body and blades as functional attachments is carried out.Natural frequencies and mode shapes of the blades are fi rst calculated,and the effects of the natural frequencies in both dry and wet conditions are taken into account.Modal analysis and harmonic response analysis of the bracket with different lengths by removing the blades are also carried out,and the different var-iations of the natural frequencies between several bracket units are compared.The responses of the key position of the bracket under different loads and different bracket lengths are analyzed.The influence of liquid on the natural frequency of the blades and the influence of the length of the bracket on the natural fre-quency of the bracket are discussed in the fluid-solid coupling state.Research in this paper provides a data basis for the safety assessment of the breakwater construction.

关键词： Breakwater modal analysis fuid-structure interaction finite element simulation

Secondary prevention medication persistence and prognosis of acute ischaemic stroke or transient ischaemic attack

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Stroke & Vascular Neurology 2021年第3期6卷 376-383,I0009-I0017页

作者： Lei Zhang Junfeng Shi Yuesong Pan Zixiao Li hongyi yan Chelsea Liu Wei Lv Xia Meng Yongjun Wang Department of Neurology Beijing Tiantan HospitalCapital Medical UniversityBeijingChina Changping District Hospital BeijingChina Yixing People’s Hospital Jiangsu ProvinceChina China National Clinical Research Center for Neurological Diseases BeijingChina Department of Epidemiology Johns Hopkins Bloomberg School of Public HealthJohns Hopkins UniversityBaltimoreMarylandUSA

Introduction The risk of disability and mortality is high among recurrent stroke,which highlights the importance of secondary prevention measures.We aim to evaluate medication persistence for secondary prevention and the prognosis of acute ischaemic stroke or transient ischaemic attack(TIA)in China.Methods Patients with acute ischaemic stroke or TIA from the China National Stroke Registry II were divided into 3 groups based on the percentage of persistence in secondary prevention medication classes from discharge to 3 months after onset(level I:persistence=0%,level II:0%

关键词： prevention medication acute

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红层地区高铁路堑基底上拱等级预测研究

土木工程学报 2024年第2期57卷 107-116页

作者：颜宏毅赵晓彦陈明浩蹇黎明张广泽西南交通大学四川成都611756 中铁二院工程集团有限责任公司四川成都610031

轨面平顺性是高速铁路安全运行的重要保证。近年来,四川红层部分高速铁路(客运专线)出现路基上拱病害,致使轨面不平顺并影响高铁正常运营。对于高速铁路无砟轨道线路,基底上拱整治十分困难,如能在铺轨前进行上拱预测,就可采取相应措施... 详细信息

轨面平顺性是高速铁路安全运行的重要保证。近年来,四川红层部分高速铁路(客运专线)出现路基上拱病害,致使轨面不平顺并影响高铁正常运营。对于高速铁路无砟轨道线路,基底上拱整治十分困难,如能在铺轨前进行上拱预测,就可采取相应措施以减缓路基上拱,因此高铁路基上拱预测研究势在必行。以成渝客运专线为研究对象,在综合分析路基上拱主要影响因素的基础上,选取路基中心开挖深度、岩层倾角、砂泥岩互层关系、泥岩饱和单轴抗压强度、泥岩膨胀性5个评价指标,采用熵权法确定各指标权重,运用功效系数法建立高铁红层路基上拱等级预测模型。将该模型应用于成渝客专和沪渝蓉高铁建设前期主要上拱段及上拱等级预测,验证了该模型的可行性与实用性。

关键词：高速铁路红层泥岩基底上拱预测熵权法功效系数法

Endovascular treatment with or without intravenous alteplase for acute ischaemic stroke due to basilar artery occlusion

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Stroke & Vascular Neurology 2022年第3期7卷 190-199页

作者： Ximing Nie David Wang Yuehua Pu Yufei Wei Qixuan Lu hongyi yan Xin Liu Lina Zheng Jingyi Liu Xinxuan yang Yarong Ding Dacheng Liu Wanying Duan Zhe Zhang Zhonghua yang Miao Wen Weibin Gu Xinyi Hou Xinyi Leng Yuesong Pan Zhongrong Miao Liping Liu Department of Neurology Beijing Tiantan HospitalCapital Medical UniversityBeijingChina China National Clinical Research Center for Neurological Diseases BeijingChina Neurovascular Division Department of NeurologyBarrow Neurological InstitutePhoenixArizonaUSA Department of Medicine and Therapeutics Prince of Wales HospitalHong KongChina Department of Radiology Beijing Tiantan HospitalCapital Medical UniversityBeijingChina Department of Interventional Neurology Beijing Tiantan HospitalCapital Medical UniversityBeijingChina

Background and purpose It remains controversial if endovascular treatment(EVT)can improve the outcome of patients with acute basilar artery occlusion(BAO).This study aims to compare the functional outcomes between EVT with and without intravenous thrombolysis(IVT)first in patients who had acute ischaemic stroke(AIS)due to BAO.Methods Patients who had AIS with BAO who underwent EVT within 24 hours of onset were enrolled in this multicentre cohort study,and the efficacy and safety were compared between IVT+EVT and direct EVT.The primary outcome was 90-day functional independence.All outcomes were assessed with adjusted OR(aOR)from the multivariable logistic regression.In addition,a meta-analysis was performed on all recently published pivotal studies on functional independence after EVT in patients with BAO.Results Of 310 enrolled patients with BAO,241(78%)were treated with direct EVT and 69(22%)with IVT+EVT.Direct EVT was associated with a worse functional outcome(aOR,0.46(95%CI 0.24 to 0.85),p=0.01).IVT+EVT was associated with a lower percentage of patients who needed≥3 passes of stent retriever(10.14%vs 20.75%).The meta-analysis regression revealed a potential positive correlation between bridging with IVT first and functional independence(r=0.14(95%CI 0.05 to 0.24),p<0.01).Conclusions This study showed that compared with direct EVT,EVT with IVT first was associated with better functional outcomes in patients with BAO treated within 24 hours of onset.The meta-analysis demonstrated similar favourable efficacy of IVT first followed by EVT in patients with BAO.

关键词： acute intravenous occlusion

Association of elevated hs-CRP and multiple infarctions with outcomes of minor stroke or TIA: subgroup analysis of CHANCE randomised clinical trial

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Stroke & Vascular Neurology 2021年第1期6卷 80-86页

作者： Guangyao Wang Jing Jing Jiejie Li Yuesong Pan hongyi yan Xia Meng Xingquan Zhao Liping Liu Hao Li David Z Wang Yongjun Wang Yilong Wang Department of Neurology Beijing Tiantan HospitalCapital Medical UniversityBeijingChina China National Clinical Research Center for Neurological Diseases BeijingChina Neurovascular Division Department of NeurologyBarrow Neurological InstituteSt.Joseph's Hospital and Medical CenterPhoenixArizonaUSA

Background and purpose The relationship of high-sensitive C-reactive protein(hs-CRP)levels and infarction numbers with the prognosis of stroke is uncertain.This study evaluated the association of different hs-CRP levels and infarction numbers with the prognosis of acute minor ischaemic stroke or transient ischaemic attack(TIA).Methods A subset of 807 patients with both hs-CRP measurement and baseline MRI was included from the Clopidogrel in High-risk Patients with Acute Non-disabling Cerebrovascular Events trial.The primary efficacy outcome was the occurrence of an ischaemic stroke at the 1-year follow-up.Infarction numbers were classified as multiple acute infarctions(MAIs),single acute infarction and no acute infarction(NAI).The association between different hs-CRP levels with different infarction numbers and the risk of any outcome was analysed using multivariable Cox regression models.Results Among the 807 patients,84(10.4%)patients had a recurrent ischaemic stroke within 1 year.After adjustment for conventional confounding factors,patients with both elevated hs-CRP levels and MAIs were associated with approximately 4.7-fold of risk of ischaemic stroke within 1 year(16.7% vs 3.5%,HR 4.68,95% CI 1.54 to 14.23,p=0.007),compared with those with non-elevated hs-CRP levels and NAI.Similar results were observed for the composite events.Conclusions Combined elevated hs-CRP levels and MAIs may increase 1-year stroke risk stratification efficiency in patients with minor ischaemic stroke or TIA compared with using those markers alone,which indicated that the combination of inflammatory and imaging markers might improve the effectiveness of risk stratification concerning minor ischaemic stroke or TIA.

关键词： elevated infarction minor

高性能多层氧化石墨烯基复合水凝胶的可控合成方法研究

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化工新型材料 2024年第4期52卷 83-87,92页

作者：郑静李晓燕马欣艳闫鸿熠王晨柴涛中北大学环境与安全工程学院太原030051 山西北方兴安化学工业有限公司太原030051

以多层氧化石墨烯(GO)为原料,羟丙基纤维素(HPC)为骨架,采用溶剂热法制备还原氧化石墨烯复合海绵的前驱物——三维还原氧化石墨烯复合水凝胶。考察分散液配比、置换程度、pH、反应时间与温度、HPC添加量等因素对水凝胶成型性的影响。结... 详细信息

以多层氧化石墨烯(GO)为原料,羟丙基纤维素(HPC)为骨架,采用溶剂热法制备还原氧化石墨烯复合海绵的前驱物——三维还原氧化石墨烯复合水凝胶。考察分散液配比、置换程度、pH、反应时间与温度、HPC添加量等因素对水凝胶成型性的影响。结果表明:分散液中无水乙醇与去离子水最佳配比为1∶1;离心时间30min、置换次数6次时层间水分置换最彻底;pH=8、反应温度210℃、时间14h、HPC添加量10mg时制备效果最佳。

关键词：多层氧化石墨烯羟丙基纤维素复合水凝胶溶剂热法

路堑特征对高铁红层泥岩基底蠕变上拱特性影响研究

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工程地质学报 2024年第2期32卷 709-718页

作者：颜宏毅赵晓彦李臣奇陈明浩张广泽西南交通大学地质工程系成都611756 中铁十五局城建公司洛阳471000 中铁二院工程集团有限责任公司成都610031

轨面的平顺性是高速铁路(客运专线)正常运营的关键保障。近年来,红层泥岩地区深挖路堑基底持续上拱病害已导致轨面显著不平顺,严重影响高速铁路正常运营。本文以成(都)渝(重庆)客运专线内江北站为研究对象,统计沿线上拱监测数据,分析路... 详细信息

轨面的平顺性是高速铁路(客运专线)正常运营的关键保障。近年来,红层泥岩地区深挖路堑基底持续上拱病害已导致轨面显著不平顺,严重影响高速铁路正常运营。本文以成(都)渝(重庆)客运专线内江北站为研究对象,统计沿线上拱监测数据,分析路堑中心开挖深度与路基基底上拱量值的对应关系,得出开挖卸荷是导致高铁基底上拱的重要原因。分析成渝客运专线上拱段路堑特征,将深挖路堑分为双侧对称型、双侧不对称型和单侧型。通过室内侧限单轴压缩蠕变试验获得砂、泥岩蠕变曲线,采用Burgers模型对曲线进行参数识别,用Flac3D模拟内江北站深挖路堑基底上拱特性,对比分析上拱位移与侧压力系数的模拟值与实测值,验证模型的可行性。在此基础上,模拟分析3种堑型基底上拱特性,得到最不利堑型。最后以最不利堑型为例,研究不同开挖宽深比、不同堑坡坡度下的基底泥岩上拱特性,得到最不利宽深比和坡角。研究结果可为高速铁路红层泥岩的路堑设计提供参考。

关键词：高速铁路红层泥岩堑坡特征卸荷蠕变数值模拟

Cerebral small vessel disease or intracranial large vessel atherosclerosis may carry different risk for future strokes

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Stroke & Vascular Neurology 2020年第2期5卷 128-137页

作者： Huimin Chen Yuesong Pan Lixia Zong Jing Jing Xia Meng Yuyuan Xu hongyi yan Xingquan Zhao Liping Liu Hao Li S Claiborne Johnston Yongjun Wang Yilong Wang Department of Neurology Beijing Tiantan HospitalCapital Medical UniversityBeijingChina China National Clinical Research Center for Neurological Diseases(NCRC-ND) BeijingChina Advanced Innovation Center for Human Brain Projection Capital Medical UniversityBeijingChina Dell Medical School University of TexasAustinTexasUSA

Background The effect of cerebral small vessel disease(CSVD)and intracranial arterial stenosis(ICAS)on stroke outcomes remains unclear.Methods Data of 1045 patients with minor stroke or transient ischaemic attack(TIA)were obtained from 45 sites of the Clopidogrel in High-Risk Patients with Acute Non-disabling Cerebrovascular Events(CHANCE)trial.We assessed the associations of burdens of CSVD and ICAS with new strokes and bleeding events using multivariate Cox regression models and those with modified Rankin Scale(mRS)scores using ordinal logistic regression models.Results Among the 1045 patients,CSVD was present in 830 cases(79.4%)and ICAS in 460(44.0%).Patients with>1 ICAS segment showed the highest risk of new strokes(HR 2.03,95%CI 1.15 to 3.56,p=0.01).No association between CSVD and the occurrence of new strokes was found.The presence of severe CSVD(common OR(cOR)2.01,95%CI 1.40 to 2.89,p1 ICAS segment(cOR 2.15,95%CI 1.57 to 2.93,p<0.001)was associated with higher mRS scores.Severe CSVD(HR 10.70,95%CI 1.16 to 99.04,p=0.04),but not ICAS,was associated with a higher risk of bleeding events.Six-point modified CSVD score improved the predictive power for bleeding events and disability.Interpretation CSVD is associated with more disability and bleeding events,and ICAS is associated with an increased risk of stroke and disability in patients with minor stroke and TIA at 3 months.CSVD and ICAS may represent different vascular pathologies and play distinct roles in stroke outcomes.

关键词： intracranial bleeding Acute

Inconsistent centralised versus noncentralised ischaemic stroke aetiology

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Stroke & Vascular Neurology 2020年第4期5卷 337-347页

作者： Yue Suo Jing Jing Xia Meng Zixiao Li Yuesong Pan Yong Jiang Xiaomeng yang Huan Liu hongyi yan Liping Liu Xingquan Zhao Yilong Wang Hao Li Yongjun Wang Department of Neurology Beijing Tiantan HospitalBeijingChina China National Clinical Research Center for Neurological Diseases BeijingChina

Background and purpose The Trial of Org 10172 in Acute Stroke Treatment(TOAST)system is the most widely used aetiological categorisation system in clinical practice and research.Limited studies have validated the accuracy of routine aetiological diagnosis of patients with ischaemic stroke according to the TOAST criteria when the reported subtype is assumed to be correct.We investigated the agreement between centralised and non-centralised(site-reported,at discharge)stroke subtypes in the Third China National Stroke Registry(CNSR-III),and analysed the influence of classification consistency on evaluation during hospitalisation and for secondary prevention strategy.Methods All patients with ischaemic stroke from the CNSR-III study with complete diffusion-weighted imaging data were included.We used multivariable Cox proportional-hazard regression models to evaluate the factors associated with consistency between centralised and non-centralised stroke subtypes.Sensitivity analyses were conducted of the subgroup of patients with complete information.Results This study included 12180 patients(mean age,62.3 years;and women,31.4%).Agreement between centralised and non-centralised subtype was the highest for the large-artery atherosclerosis subtype stroke(77.4%of centralised patients),followed by the small-vessel occlusion subtype(40.6%of centralised patients).Agreements for cardioembolism and stroke of other determined aetiology subtypes were 38.7%and 12.2%,respectively.Patient-level and hospital-level factors were associated with the inconsistency between centralised/non-centralised aetiological subtyping.This inconsistency was related to differences in secondary prevention strategies.Only 15.3%of the newly diagnosed patients with cardioembolism underwent centralised subtyping with indications to receive oral anticoagulants at discharge.In comparison,51.3%of the consistent cardioembolism group and 42.0%of the centrally reassigned cardioembolism group with anticoagulation indications were prescribed oral anticoagulants.C

关键词： prevention routine diagnosis