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Experimental Study on Interference Effect of Three Risers Arranged in Tandem with Variable Spacing Ratios

China Ocean Engineering 2023年第3期37卷 408-419页

作者： ZHANG Peng LIU Li-hua LIU Ming ren xiao-hui WANG Yu School of Civil Engineering Qingdao University of TechnologyQingdao 266520China College of Civil Engineering and Architecture Shandong University of Science and TechnologyQingdao 266590China Shandong Provincial Key Laboratory of Civil Engineering Disaster Prevention and Mitigation Qingdao 266590China School of Petroleum Engineering China University of Petroleum(East China)Qingdao 266580China

Taking the three-riser group arranged in tandem as the research subject,an experimental study was carried out on the risers arranged in *** purpose is to explore the sensitivity of the dynamic response of each riser to spacing ratio and reveal the physical mechanism of riser groups under the interference *** spacing ratios of the adj acent risers are 4.0,5.0,6.0,and *** the spacing between the risers of 4.0D,the strong feedback effect increases the cross-flow(CF) displacement amplitude of the upstream *** shielding effect is the key factor affecting the interference effect on the midstream and downstream *** low reduced velocities,the shielding area initially appears,the displacement amplitude of the midstream and downstream risers varies greatly,the vibration of the two risers is still dominated by the first-order mode,and the transition between adjacent vibration modes is *** multi-frequency superposition phenomenon is very significant at high reduced *** most sensitive interference spacing under the test conditions is *** to the separation of the incoming flow and the double shielding effect of the upstream and midstream risers,the regular vortex-induced vibration in the wake area of the downstream riser is broken,and the vibration in the two directions is *** general,the interference effect is more significant for the CF vibration of the three-riser groups than the in-line(IL) vibration.

关键词： three-riser group tandem arrangement vortex-induced vibration wake interference variable spacing ratios

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Experimental Investigation of Multi-Mode Vortex-Induced Vibration of Flexible Risers with Different Mass Ratios

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China Ocean Engineering 2023年第1期37卷 1-15页

作者： WANG Yu LOU Min ren xiao-hui LIANG Wei-xing LI Xiang DANG Peng-bo School of Petroleum Engineering China University of Petroleum(East China)Qingdao 266580China Key Laboratory of Unconventional Oil&Gas Development(China University of Petroleum(East China)) Ministry of EducationQingdao 266580China College of Civil Engineering and Architecture Shandong University of Science and TechnologyQingdao 266590China

Experiments were conducted on risers with different mass ratios to study the effect of mode conversion and spanwise correlation. The slenderness ratio of the riser model was set as 169, and the Reynolds numbers are 1600-14400. The dynamic responses of riser models versus reduced velocity were analyzed, and the spanwise displacement, frequency,and trajectory of the mode conversion from the lower to the higher mode were explored. The results revealed that the riser model with a higher mass ratio excites a higher number of modes. The conversion region of multi-mode competition exists and narrows with the increasing mass ratio. Mode conversion is continuous and manifests as the transmission of peaks and troughs in mode shape: the peaks and troughs of mode shape move up in the mode stable development region and move down in the mode conversion region. The single-mode dominating vibration exhibits a standing wave feature, and the traveling wave feature is significant in the mode conversion region. Furthermore, the frequency jump is always transmitted from the trough to the peak of the mode shape, and finally, all the axial positions vibrate at the same frequency. The trajectory in the mode conversion region deviates from the 8-shape and recovers the standard8-shape at the middle and late stages of the mode stable development region.

关键词： vortex-induced vibration dynamic response mode conversion mass ratio mode weight

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Experimental Study on Vortex-Induced Vibration of Rough Risers Coupling with Interference Effect in Tandem Arrangement

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China Ocean Engineering 2024年第3期38卷 394-407页

作者： HU Ze-bo LIU Zhen LI Peng GUO Hai-yan ren xiao-hui HOU Hao HAO Lian-hong College of Civil Engineering and Architecture Shandong University of Science and TechnologyQingdao 266590China Qingdao Key Laboratory of Marine Civil Engineering Materials and Structures Qingdao 266590China College of Engineering Ocean University of ChinaQingdao 266100China

In order to study the response law of vortex-induced vibration(VIV)of marine risers under the combined action of roughness and interference effects,and to reveal the coupling mechanism of roughness and interference effects on the riser,a VIV experiment of rough risers in tandem arrangement was conducted in a wave−current combined *** experiment characterized the risers’roughness by arranging different specifications of attachments on the surface of the *** rough risers with different roughness and smooth risers were arranged in tandem arrangement,with the rough risers arranged *** experimental results indicate that the suppression of the attachments on the downstream risers’vibration are more significant both in the CF and IL directions as the reduced velocity *** the downstream riser,the amplitude response of rough riser is more significantly weakened compared with the smooth one at high reduced *** the upstream risers,changes in the roughness and spacing ratio have an impact on their‘lock-in’*** the roughness of downstream risers is relatively large(0.1300)and the spacing between risers is small(S/D=4.0),the reduced velocity range of‘lock-in’region in the CF direction of upstream risers is obviously expanded,and the displacement in the‘lock-in’region is severer.

关键词： marine riser vortex-induced vibration tandem arrangement roughness interference effect

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Experimental Study on Vortex-Induced Vibration of Rough Risers with Coupling Interference Effect Under Side-by-Side Arrangement

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China Ocean Engineering 2024年第1期38卷 18-28页

作者： HU Ze-bo LIU Zhen LI Peng GUO Hai-yan WANG Shu-bing ren xiao-hui HOU Hao WANG Ye-shuo College of Civil Engineering and Architecture Shandong University of Science and TechnologyQingdao 266590China Qingdao Key Laboratory of Marine Civil Engineering Materials and Structures Qingdao 266590China College of Engineering Ocean University of ChinaQingdao 266100China CHEC Dredging Co. LtdShanghai 200136China

A vortex-induced vibration(VIV)experiment of rough risers with coupling interference effect under a side-by-side arrangement was carried out in a wave-current combined *** roughness of the riser was characterized by arranging different specifications of surface attachments on the surface of the *** risers with three different roughnesses were arranged side by side with smooth risers to explore the VIV response of the riser under the combined action of roughness and interference effect,and to reveal the coupling mechanism between roughness and interference *** experimental results show that,compared with that of a smooth riser,the VIV of a rough riser under the coupling interference effect has a wider"lock-in"region,and the displacement decreases more significantly at a high reduced velocity,which is more likely to excite higher-order modes and frequency *** addition,the displacement response and frequency response of the smooth riser are not significantly affected by wake interference from the rough riser,which is caused by the decrease of the wake region due to the delay of the boundary layer separation point of the rough riser.

关键词： marine riser vortex-induced vibration side-by-side arrangement roughness interference effect

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Experimental Study on Vortex-Induced Vibration of Marine Riser Model with Coupling Interference Effect Under Combined Internal and External Flow

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China Ocean Engineering 2023年第4期37卷 673-684页

作者： ren xiao-hui LI Peng CHEN Xin WANG Ye-shuo LIU Zhen HAO Lian-hong WANG Yu HUANG Yi-jie College of Architecture and Civil Engineering Shandong University of Science and TechnologyQingdao 266590China Qingdao Key Laboratory of Marine Civil Engineering Materials and Structures Qingdao 266590China School of Petroleum Engineering China University of Petroleum(East China)Qingdao 266580China

A partition model of interference efficiency was constructed to study the coupling interference effect under combined internal and external *** concept of“internal flow efficiency”,“velocity ratio”and“interference efficiency”were introduced to quantify the effect of internal flow and interference,and reveal the coupling mechanism among internal flow,external flow and interference *** results showed that the dynamic response of risers under variable angles was significantly different after considering the effect of internal *** the external flow velocity was smaller than 0.25 m/s,the vibration of risers was promoted by the internal *** the increase of external flow velocity,the effect of internal flow was weakened and the dynamic response of riser mainly depended on the external flow and interference *** the effect of different internal flow,the interference efficiency had similar change *** interference effect amplified the complex secondary flow effect inside the riser,making the dynamic response of riser complex and *** this paper,the overlap area and subdivision criterion of interference effect were constructed within the range of experimental velocity ratio,and the change curve of interference efficiency was obtained with an average meaning,which may have important practical meaning.

关键词： marine riser vortex-induced vibration internal flow interference effect interference efficiency internal flow efficiency

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子女代际支持对老年人就医行为的影响研究

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四川大学学报（医学版） 2023年第3期54卷 614-619页

作者：任青蔓任晓晖四川大学华西公共卫生学院/四川大学华西第四医院健康行为与社会医学系成都610041

目的探究子女代际支持对老年人就医行为的影响,为促进老年人合理就医提供建议。方法使用中国家庭追踪调查(China Family Panel Studies,CFPS)2016年基线数据与2018年全国追踪数据,选择60岁及以上、有健在子女的居民5690人。使用logisti... 详细信息

目的探究子女代际支持对老年人就医行为的影响,为促进老年人合理就医提供建议。方法使用中国家庭追踪调查(China Family Panel Studies,CFPS)2016年基线数据与2018年全国追踪数据,选择60岁及以上、有健在子女的居民5690人。使用logistic回归分析子女代际支持对老年人就医行为的影响。结果子女提供经济支持的老年人两周就诊的概率相对较高(OR=1.129,95%CI:1.004~1.271,P0.05)。子女提供日常照料支持对老年人两周就诊和过去一年住院服务利用均有促进作用(OR=1.155,95%CI:1.021~1.307,P0.05)。结论子女代际支持对老年人就医行为有着重要的影响。应发挥子女代际支持的优势作用,同时完善正式社会支持渠道以缓解子女代际支持压力,为促进老年人合理就医提供建议,以进一步提高老年人整体健康水平。

关键词：子女代际支持就医行为老年人

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义务教育支出绩效评价指标体系设计

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华中师范大学学报（人文社会科学版） 2008年第4期47卷 16-21页

作者：任晓辉上海财经大学中国教育支出绩效评价中心上海200433

教育支出绩效评价的核心是建立起一套科学、可行的指标体系。本文应用绩效评价原理,结合我国义务教育管理的实践活动特征,从投入、产出与结果和教育发展能力三个角度设计出一套完整的义务教育支出绩效评价指标体系,能够同时满足财政部... 详细信息

教育支出绩效评价的核心是建立起一套科学、可行的指标体系。本文应用绩效评价原理,结合我国义务教育管理的实践活动特征,从投入、产出与结果和教育发展能力三个角度设计出一套完整的义务教育支出绩效评价指标体系,能够同时满足财政部门对教育部门和教育部门对具体学校两个不同层次的评价。

关键词：义务教育公共支出绩效评价指标体系

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中等职业教育财政支出绩效评价指标设计与应用——基于上海A区案例分析

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华中师范大学学报（人文社会科学版） 2010年第6期49卷 148-153页

作者：任晓辉上海财经大学公共经济与管理学院上海200433

立足于我国中等职业教育发展的现实背景和特征,本文以上海A区2007年、2009两年的中等职业教育财政支出绩效评价实践为例,通过指标解析和评价结果分析,深刻地揭示出现阶段东部地区中等职业教育发展在经费、生源、专业、师资、毕业生就业... 详细信息

立足于我国中等职业教育发展的现实背景和特征,本文以上海A区2007年、2009两年的中等职业教育财政支出绩效评价实践为例,通过指标解析和评价结果分析,深刻地揭示出现阶段东部地区中等职业教育发展在经费、生源、专业、师资、毕业生就业和对外服务等方面出现的问题,并从绩效的角度提出了扩大生源、规划专业设置、提高师资水平,改革拨款和财务管理方式、提升就业质量和建立绩效评价常态机制等项政策建议。

关键词：中等职业教育财政支出绩效评价扩大职教规模专业设置校企合作

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社区社会环境与中老年居民自评健康的相关性研究

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四川大学学报（医学版） 2021年第6期52卷 992-1000页

作者：张红任晓晖四川大学华西公共卫生学院/四川大学华西第四医院健康行为与社会医学系成都610041

目的分析社区社会环境对社区中老年居民自评健康的影响,为构建良好的社区社会环境、促进社区中老年人群健康提供依据。方法利用2011年中国健康与养老追踪调查(China Health and Retirement Longitudinal Study,CHARLS)社区和家户调查数... 详细信息

目的分析社区社会环境对社区中老年居民自评健康的影响,为构建良好的社区社会环境、促进社区中老年人群健康提供依据。方法利用2011年中国健康与养老追踪调查(China Health and Retirement Longitudinal Study,CHARLS)社区和家户调查数据,选取397个社区的7 822名中老年人为研究对象。社区社会环境包括社区社会经济地位、社区社会保障和社区服务三类,自评健康采用五个等级评分。采用三水平广义线性模型分析社区社会环境对中老年自评健康的影响。结果自评健康不好的比例为28.8%。三水平广义线性模型结果显示,中老年居民自评健康在城市和社区层面均存在差异,并且社区水平方差缩减比达到35.71%。中、高人均纯收入社区相比低人均纯收入社区,其居民自评健康状况更好(OR=0.84,P<0.05;OR=0.70,P<0.05)。中、高文化程度社区相比低文化程度社区,其居民自评健康状况更好(OR=0.78,P<0.05;OR=0.73,P<0.05)。实行失业补贴的社区其中老年居民自评健康状况更好(OR=0.77,P<0.05)。个体水平上,患有慢性病的中老年人自评健康状况更差(OR=4.46,P<0.05)。城市的中老年自评健康状况较农村更好(OR=0.76,P<0.05)。结论社区社会经济地位和社区失业补贴与社区中老年居民自评健康呈正相关。需要特别关注低社会经济地位社区的中老年人健康状况,完善失业保障政策,促进社区中老年居民健康。

关键词：中老年自评健康社区社会环境三水平广义线性模型

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Induced pluripotent stem cell-related approaches to generate dopaminergic neurons for Parkinson's disease

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Neural Regeneration Research 2025年第11期20卷 3193-3206页

作者： Ling-xiao Yi hui ren Woon Genevieve Saw Li Zeng Eng King Tan Zhi Dong Zhou National Neuroscience Institute Singapore Nanyang Technology University Singapore Department of Neurology Singapore General HospitalSingapore Signature Research Program in Neuroscience and Behavioral Disorders Duke-NUS Medical SchoolSingapore

The progressive loss of dopaminergic neurons in affected patient brains is one of the pathological features of Parkinson's disease,the second most common human neurodegenerative *** the detailed pathogenesis accounting for dopaminergic neuron degeneration in Parkinson's disease is still unclear,the advancement of stem cell approaches has shown promise for Parkinson's disease research and *** induced pluripotent stem cells have been commonly used to generate dopaminergic neurons,which has provided valuable insights to improve our understanding of Parkinson's disease pathogenesis and contributed to anti-Parkinson's disease *** current review discusses the practical approaches and potential applications of induced pluripotent stem cell techniques for generating and differentiating dopaminergic neurons from induced pluripotent stem *** benefits of induced pluripotent stem cell-based research are *** dopaminergic neuron differentiation protocols from induced pluripotent stem cells are *** emerging three-dimension-based brain organoid models compared with conventional two-dimensional cell culture are ***,limitations,challenges,and future directions of induced pluripotent stem cell–based approaches are analyzed and proposed,which will be significant to the future application of induced pluripotent stem cell-related techniques for Parkinson's disease.

关键词： dopaminergic neurons induced pluripotent stem cells Parkinson's disease stem cell approaches

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