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深水隔水管-水下井口耦合系统双向涡激振动特性

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力学学报 2024年第3期56卷 550-564页

作者：胡鹏基李朝玮刘秀全刘兆伟畅元江陈国明中国石油大学(华东)机电工程学院海洋油气装备与安全技术研究中心山东青岛266580 常州大学石油与天然气工程学院江苏常州213164

深水隔水管-水下井口系统极易受外部海流影响产生涡激振动(VIV),其VIV分析通常将底端水下井口简化为固支约束.考虑水下井口下部非线性管-土耦合建立深水隔水管-水下井口耦合系统顺流(IL)及横流(CF)向VIV三维分析模型.基于胡克定律将管-... 详细信息

深水隔水管-水下井口系统极易受外部海流影响产生涡激振动(VIV),其VIV分析通常将底端水下井口简化为固支约束.考虑水下井口下部非线性管-土耦合建立深水隔水管-水下井口耦合系统顺流(IL)及横流(CF)向VIV三维分析模型.基于胡克定律将管-土相互作用产生的时变非线性土壤抗力转化为时变土壤等效刚度并与系统结构刚度叠加.采用有限单元法进行分析模型离散,采用Newmark-β法与4阶龙格库塔法进行VIV数值求解.随后分别研究了管-土耦合作用及环境因素如海流流速、土壤硬度等对深水隔水管-水下井口系统CF及IL方向VIV特性的影响.结果表明,考虑管-土耦合的深水隔水管-水下井口系统约束弱化,系统整体刚度减小,固有频率降低,深水隔水管-水下井口系统CF及IL方向的均方根(RMS)位移及振幅增大,振动频率减小.深水隔水管-水下井口系统VIV对土壤硬度的敏感度较低,原因是系统结构刚度与土壤初始附加的等效刚度较大,而土壤硬度变化额外附加的土壤等效刚度在系统总刚度中的占比较低.

关键词：隔水管-水下井口管-土耦合尾流振子涡激振动

六盘山地区新生代构造演化:来自锆石和磷灰石裂变径迹的证据

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地球物理学报 2024年第3期67卷 1147-1168页

作者：陈国明覃焕图黄兴富郭晓玉高锐李旭成张逸鹏桂林理工大学地球科学学院&广西隐伏金属矿产勘查重点实验室桂林541004 中山大学地球科学与工程学院广州510275 中国冶金地质总局广西地质勘查院南宁530000

青藏高原的隆升与扩展不仅导致欧亚大陆内部发生强烈的构造变形,亦对高原周缘的地貌格局及气候变化产生了重大影响.青藏高原东北缘新生代以来的隆升时代与响应过程一直备受争议,而界定青藏高原东北缘构造带隆升时序是解决争议的关键之一... 详细信息

青藏高原的隆升与扩展不仅导致欧亚大陆内部发生强烈的构造变形,亦对高原周缘的地貌格局及气候变化产生了重大影响.青藏高原东北缘新生代以来的隆升时代与响应过程一直备受争议,而界定青藏高原东北缘构造带隆升时序是解决争议的关键之一.本研究围绕青藏高原东北缘,在陇中盆地、六盘山褶皱逆冲带和鄂尔多斯地块西南缘地区进行了磷灰石和锆石裂变径迹测试分析和热史模拟.测试分析结果表明研究区样品的磷灰石裂变径迹年龄范围分布于136~16 Ma,裂变径迹的长度范围介于11.9~13.3μm;锆石裂变径迹年龄结果为258~79 Ma,但多数样品的年龄介于160~99 Ma;热史模拟结果揭示了研究区新生代以来至少经历了两期隆升和冷却降温事件,即始新世期间(55~30 Ma)和中中新世(17~12 Ma)以来.始新世期间(55~30 Ma)发生的隆升事件可能是印度大陆与欧亚大陆陆陆碰撞远程效应的直接响应,表明印度与欧亚大陆碰撞之初或不久,其应力即已传导至东北缘边界;中中新世(17~12 Ma)以来的隆升剥露冷却事件奠定了青藏高原东北缘现今构造格局.

关键词：青藏高原东北缘六盘山构造演化低温热年代学裂变径迹

维普期刊数据库博看期刊

融合PSO-模糊Petri网的室内燃气泄漏风险研究

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安全与环境学报 2024年第2期24卷 440-449页

作者：张新琪陈国明黄佳伟王朝阳刘康乔千哲中国石油大学(华东)海洋油气装备与安全技术研究中心山东青岛266000 中国石化天然气分公司北京100029

近年来室内燃气事故多发,而燃气用户风险意识淡薄、户内安全检查难度大。针对现行室内燃气安全管理技术多为静态主观评估的局限性,构建了基于模糊Petri网(Fuzzy Petri Net,FPN)的风险计算规则,提出了结合粒子群优化算法(Particles Swarm... 详细信息

近年来室内燃气事故多发,而燃气用户风险意识淡薄、户内安全检查难度大。针对现行室内燃气安全管理技术多为静态主观评估的局限性,构建了基于模糊Petri网(Fuzzy Petri Net,FPN)的风险计算规则,提出了结合粒子群优化算法(Particles Swarm Optimization,PSO)和FPN的室内燃气泄漏动态风险评估模型。首先,应用Petri网的直观图像描述和异步并发处理能力建立室内燃气泄漏事故风险演化的拓扑结构模型,借助FPN的模糊推理能力处理风险传播的不确定性;然后,根据燃气运维数据,融合PSO动态更新初始参数,提高风险评估的准确性。结果表明,基于PSO-FPN的室内风险评估方法可弱化燃气公司安检人员分析的主观不确定性,更为准确地量化风险因子演化过程,实现室内燃气泄漏风险的动态分析,有效支持户内燃气泄漏风险管控。

关键词：安全工程室内燃气风险评估模糊Petri网(FPN) 粒子群优化算法(PSO)

紧急关断系统对天然气泄漏灾变事故后果的影响

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中国安全生产科学技术 2024年第3期20卷 77-82页

作者：肖丰浦董海张军李亚楠杨冬冬陈国明新疆油田公司工程技术研究院新疆克拉玛依834000 中国石油大学(华东)海洋油气装备与安全技术研究中心山东青岛266580

为明确紧急关断(emergency shutdown,ESD)系统对天然气泄漏灾变危险载荷发展特性的影响,以天然气开发地面处理工艺系统为研究对象,建立天然气泄漏灾变事故后果预测评估模型,研究ESD系统响应下天然气的空间运移和燃爆行为,并与ESD系统未... 详细信息

为明确紧急关断(emergency shutdown,ESD)系统对天然气泄漏灾变危险载荷发展特性的影响,以天然气开发地面处理工艺系统为研究对象,建立天然气泄漏灾变事故后果预测评估模型,研究ESD系统响应下天然气的空间运移和燃爆行为,并与ESD系统未响应时的预测结果进行对比。研究结果表明:ESD系统有助于降低气体泄漏速率,从而影响泄漏天然气的扩散行为及其燃爆特性,大幅减缓窒息灾害效应并阻断天然气泄漏事故的灾变升级,因此,评估天然气泄漏灾变事故后果时应考虑ESD系统的响应。研究结果可为油气处理作业防灾减灾措施的设计与优化提供参考。

关键词： ESD系统天然气时变泄漏速率泄漏灾变减缓效果

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深水水下井口全钻井过程波激疲劳精细化评估

石油机械 2024年第9期52卷 74-80,105页

作者：李家仪刘秀全许亮斌邱娜畅元江陈国明赵苏文浙江科技学院机械与能源工程学院中国石油大学(华东)海洋油气装备与安全技术研究中心中山大学中海油能源发展股份有限公司工程技术深水钻采技术公司

传统的水下井口波激疲劳评估没有考虑不同钻井阶段水下井口结构组成变化,导致水下井口波激疲劳评估精度有限。为此,提出基于整体-局部交互分析的全钻井过程水下井口波激疲劳损伤精细化评估方法,建立钻井全过程复杂结构水下井口局部精细... 详细信息

传统的水下井口波激疲劳评估没有考虑不同钻井阶段水下井口结构组成变化,导致水下井口波激疲劳评估精度有限。为此,提出基于整体-局部交互分析的全钻井过程水下井口波激疲劳损伤精细化评估方法,建立钻井全过程复杂结构水下井口局部精细模型及平台-隔水管-水下井口-导管耦合系统整体模型,研究整体模型与局部模型交互机制,并构建整体模型与局部应力传递关系,精细化评估水下井口全钻井过程波激疲劳损伤。研究结果表明:全钻井过程水下井口结构组成变化对隔水管系统和远离泥线导管处的波激疲劳几乎无影响,但对水下井口局部及泥线附近导管的波激疲劳存在较大影响;钻井第二阶段水下井口波激疲劳损伤最为严重,且水下井口底端始终为疲劳极限位置。所得结论有助于判断钻井过程中水下井口疲劳状态,保证作业安全。

关键词：水下井口全钻井过程整体-局部交互分析波激疲劳疲劳损伤评估

The impact of Typhoon Lekima (2019) on East China: a postevent survey in Wenzhou City and Taizhou City

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Frontiers of Earth Science 2022年第1期16卷 109-120页

作者： Cong ZHOU Peiyan chen Shifang YANG Feng ZHENG Hui YU Jie TANG Yi LU guoming chen Xiaoqing LU Xiping ZHANG Jing SUN Shanghai Typhoon Institute of China Meteorological Administration Shanghai 200030China Department of Atmospheric and Oceanic Sciences Fudan UniversityShanghai 200438China Key Laboratory of Numerical Modeling for Tropical Cyclones China Meteorological Administration Shanghai 200030China The Joint Laboratory for Typhoon Forecasting Technique Applications between Shanghai Typhoon Institute and Wenzhou Meteorological Bureau Wenzhou 325000China Taizhou Meteorological Bureau Taizhou 318000China Wenzhou Meteorological Bureau Wenzhou 325000China

Typhoon Lekima(2019)struck Zhejiang Province on 10 August 2019 as a supertyphoon,which severely impacted Zhejiang *** typhoon killed 45 people and left three others missing,and the total economic loss reached 40.71 billion *** paper reports a postdisaster survey that focuses on the storm precipitation,flooding,landslides,and weather services associated with Typhoon Lekima(2019)along the southeastern coastline of Zhejiang *** survey was conducted by a joint survey team from the Shanghai Typhoon Institute and local meteorological bureaus from 26 to 28 August,2019,approximately two weeks after the *** on this survey and subsequent analyses of the results,we hope to develop countermeasures to prevent future tragedies.

关键词： Typhoon Lekima(2019) Zhejiang Province disaster assessment postdisaster survey

Capacitive Imaging Technique for the Inspection of Composite Sucker Rod

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Chinese Journal of Mechanical Engineering 2019年第6期32卷 113-123页

作者： Kefan Wang Xiaokang Yin chen Li Wei Li guoming chen Centre for Offshore Engineering and Safety Technology China University of Petroleum (East China)

Composite sucker rod has been extensively used due to its high strength, light weight and corrosion resistive nature. However, such composite sucker rod is diffcult for conventional non-destructive evaluation(NDE) techniques to inspect because of its complex material and/or structure. It is thus useful to embark research on developing novel NDE technique to comply the inspection requirement. This work demonstrates the feasibility of using the capacitive imaging(CI) technique for the inspection of composite sucker rod. Finite element(FE) models were constructed in COMSOL to simulate the detection of defects in the glass-fiber layer and on the carbon core surface. An FE Model based inversion method is proposed to obtain the profile of the carbon core. Preliminary CI experimental results are then presented, including the detection of surface wearing defect in the glass-fiber layer, and obtaining the profile of the carbon core. A set of accelerated aging experiments were also carried out and the results indicate that the CI technique is potentially useful in evaluating the ageing status of such composite sucker rod. The CI technique described in this work shows great potential to target some challenging tasks faced in the non-destructive evaluation of composite sucker rod, including quality control, defect detection and ageing assessment.

关键词： Non-destructive evaluation Capacitive imaging Composite inspection

Local field potentials,spiking activity,and receptive fields in human visual cortex

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Science China(Life Sciences) 2024年第3期67卷 543-554页

作者： Lu Luo Xiongfei Wang Junshi Lu Guanpeng chen guoming Luan Wu Li Qian Wang Fang Fang School of Psychological and Cognitive Sciences and Beijing Key Laboratory of Behavior and Mental Health Peking UniversityBeijing 100871China School of Psychology Beijing Sport UniversityBeijing 100084China Department of Neurosurgery Sanbo Brain HospitalCapital Medical UniversityBeijing 100093China Beijing Key Laboratory of Epilepsy Epilepsy CenterSanbo Brain HospitalCapital Medical UniversityBeijing 100093China IDG/McGovern Institute for Brain Research Peking UniversityBeijing 100871China Peking-Tsinghua Center for Life Sciences Peking UniversityBeijing 100871China Beijing Institute for Brain Disorders Beijing 100069China State Key Laboratory of Cognitive Neuroscience and Learning and IDG/McGovern Institute for Brain Research Beijing Normal UniversityBeijing 100875China

The concept of receptive field(RF) is central to sensory neuroscience. Neuronal RF properties have been substantially studied in animals,while those in humans remain nearly unexplored. Here, we measured neuronal RFs with intracranial local field potentials(LFPs) and spiking activity in human visual cortex(V1/V2/V3). We recorded LFPs via macro-contacts and discovered that RF sizes estimated from lowfrequency activity(LFA, 0.5–30 Hz) were larger than those estimated from low-gamma activity(LGA, 30–60 Hz) and high-gamma activity(HGA, 60–150 Hz). We then took a rare opportunity to record LFPs and spiking activity via microwires in V1 simultaneously. We found that RF sizes and temporal profiles measured from LGA and HGA closely matched those from spiking activity. In sum, this study reveals that spiking activity of neurons in human visual cortex could be well approximated by LGA and HGA in RF estimation and temporal profile measurement, implying the pivotal functions of LGA and HGA in early visual information processing.

关键词： human visual cortex receptive field intracranial EEG local field potential spiking activity

Neural Network in Tau Decay Mode Identification

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Chinese journal of nuclear physics 1996年第3期18卷 137-144页

作者： chen, Gang chen, guoming chen, Hesheng Jin, Bingnian Tang, Xiaowei Wang, Yifang Zhang, Zhou Peking Univ Beijing China

A method of neural network identifying tau decay modes is *** systematic errors re-lated to the neural network are discussed in detail.A method is used to analyze one-prong hadronic tau de-cays in L3 experiment.

关键词： —Tau decay Neural computing Systematic error