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基于切口应力强度理论的135°拐角处应力场分析（英文）

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船舶力学 2015年第3期19卷 273-283页

作者：谌伟严仁军 nigel barltrop 杨平刘恩骞秦恺武汉理工大学交通学院船舶与海洋工程系高速船舶工程教育部重点实验室武汉430063 斯特莱斯克莱德大学船舶与海洋工程系英国格拉斯哥G40LZ

在焊接接头处,几何的不连续造成了局部的应力集中,形成了应力奇异效应,有必要做进一步的研究。文章基于切口应力强度理论,引入了奇异强度as的概念,提出了评估切口应力的简便算法,并通过一系列十字形模型进行了验证。最后,将修改表达式... 详细信息

在焊接接头处,几何的不连续造成了局部的应力集中,形成了应力奇异效应,有必要做进一步的研究。文章基于切口应力强度理论,引入了奇异强度as的概念,提出了评估切口应力的简便算法,并通过一系列十字形模型进行了验证。最后,将修改表达式的预估结果同N-SIF公式作了对比分析,结果表明该修正公式可以简单、准确地预估焊接接头处的应力。

关键词： 135°拐角应力奇异性奇异强度(as) 切口应力强度因子(N-SIF)

基于切口应力强度理论的横向角接焊接接头的疲劳强度评估（英文）

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船舶力学 2015年第9期19卷 1116-1125页

作者：谌伟严仁军 nigel barltrop 杨平刘恩骞秦恺武汉理工大学交通学院船舶与海洋工程系高速船舶工程教育部重点实验室武汉430063 斯特莱斯克莱德大学船舶与海洋工程系英国格拉斯哥C4 0LZ

在焊接接头处,由于几何的不连续造成了局部的应力集中,对其疲劳强度评估的研究是十分必要的。文章提出采用奇异强度(as)来计算接头处的几何应力,并基于N-SIF方法分析了不同几何尺寸下十字接头的疲劳强度。结果表明该修正公式可以十分简... 详细信息

在焊接接头处,由于几何的不连续造成了局部的应力集中,对其疲劳强度评估的研究是十分必要的。文章提出采用奇异强度(as)来计算接头处的几何应力,并基于N-SIF方法分析了不同几何尺寸下十字接头的疲劳强度。结果表明该修正公式可以十分简便地评估出焊接接头处的疲劳强度。

关键词：十字接头奇异强度(as) 切口应力强度因子(N—SIF) 疲劳强度

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存在奇异点的结构疲劳评估简单方法

船舶工程 2013年第6期35卷 9-14页

作者：徐丽高嵩 nigel barltrop 哈尔滨工业大学(威海)船舶与海洋工程学院山东威海264209 斯特斯克莱德大学船舶与海洋工程系

由于船舶结构整体几何形状具有内在的应力奇异性,其有限元分析结果的评估并不明确。通过对一个简单平面直角十字形拐角结构上的奇异性和裂纹尖端的奇异性进行分析,提出简化后的经验法则及一个直接的计算方法,用于计算裂纹的应力强度因... 详细信息

由于船舶结构整体几何形状具有内在的应力奇异性,其有限元分析结果的评估并不明确。通过对一个简单平面直角十字形拐角结构上的奇异性和裂纹尖端的奇异性进行分析,提出简化后的经验法则及一个直接的计算方法,用于计算裂纹的应力强度因子和基于S-N曲线疲劳分析中的应力集中系数。同时对结构中奇异点处应力场性质提出认识,对其有限元分析方法中网格的划分提供基础。

关键词：结构疲劳奇异性等效裂纹尺寸断裂力学应力强度

基于奇异强度理论135°薄板拐角的应力评估方法研究

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武汉理工大学学报 2013年第12期35卷 72-79页

作者：高嵩徐丽王大政 nigel barltrop 哈尔滨工业大学(威海)船舶与海洋工程学院威海264209 斯特斯克莱德大学船舶与海洋工程系

基于切口应力强度理论,研究奇异强度理论下的135°薄板拐角结构的应力分布,主要通过简化切口应力强度公式,引入奇异强度as(与结构尺寸关联),同时利用ANSYS数值模拟,利用MathCAD回归分析,最终提出评估切口应力的简便算法及经验公式并加... 详细信息

基于切口应力强度理论,研究奇异强度理论下的135°薄板拐角结构的应力分布,主要通过简化切口应力强度公式,引入奇异强度as(与结构尺寸关联),同时利用ANSYS数值模拟,利用MathCAD回归分析,最终提出评估切口应力的简便算法及经验公式并加以验证,为结构的强度及疲劳分析提供参考。

关键词：应力分布奇异性奇异强度(as) 切口应力强度因子(N-SIF)

nigel Wiseman:Modern Texts,Classics,Terminology,and Language-learning Material

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Chinese Medicine and Culture 2024年第1期7卷 41-50页

作者： nigel Wiseman Department of Chinese Medicine Chang Gung UniversityTaoyuan 33302China

In this article,I trace my career from an early interest in language that eventually led me to engage in Chinese medical *** in the United Kingdom in 1954,I gained a Bachelor of Arts degree in German and Spanish from the University of Heriot-Watt,*** study of Chinese took me to Taiwan,China,where I gained an interest in Chinese medicine and developed a coherent linguistic approach to Chinese medical term translation,which I and various colleagues have systematically applied in the translation and compilation of numerous works spanning modern texts,classics,dictionaries,and language-learning *** translation approach,though conforming to principles universally recognized by translation theorists,has proven to be highly controversial,with opponents in both Western and Chinese circles.

关键词： Chinese medical translation Chinese medical terminology

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基于奇异强度理论的疲劳特性评估方法

中国舰船研究 2014年第5期9卷 60-68,76页

作者：高嵩徐丽 nigel barltrop 王大政交通运输部水运科学研究院北京100088 哈尔滨工业大学(威海)船舶与海洋工程学院山东威海264209 斯特莱斯克莱德大学船舶与海洋工程系

疲劳是海洋结构物破坏的重要因素,为简化舰船结构疲劳评估方法,基于线弹性断裂力学和切口应力强度理论,针对典型薄板结构研究拐角节点处的应力强度,分析结构形式,利用ANSYS有限元模拟和MathCAD函数拟合,分别给出计算应力强度因子的"奇... 详细信息

疲劳是海洋结构物破坏的重要因素,为简化舰船结构疲劳评估方法,基于线弹性断裂力学和切口应力强度理论,针对典型薄板结构研究拐角节点处的应力强度,分析结构形式,利用ANSYS有限元模拟和MathCAD函数拟合,分别给出计算应力强度因子的"奇异权函数法"和"奇异等效裂纹法"的研究方法,同时给出简便算法和经验公式。进而应用Paris裂纹扩展法则进行结构奇异强度疲劳特性评估,并结合S-N曲线分析拐角节点处的应力集中,得到与结构尺寸相关的"奇异应力集中系数"函数。最后,针对切口应力,提出有限元分析所需要的"奇异应力等效取值点"的参考位置。希望能将奇异强度理论纳入船舶结构疲劳强度校核规范中做参考。

关键词：疲劳奇异强度应力强度因子等效裂纹权函数应力集中切口应力

Etiology and management of urethral calculi:A systematic review of contemporary series

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Asian Journal of Urology 2024年第1期11卷 10-18页

作者： Andrew Morton Arsalan Tariq nigel Dunglison Rachel Esler Matthew J.Roberts Faculty of Medicine The University of QueenslandBrisbaneQueenslandAustralia Department of Urology Ipswich HospitalQueenslandAustralia Department of Urology Royal Brisbane and Women's HospitalQueenslandAustralia The University of Queensland Centre for Clinical Research HerstonAustralia

Objective:To conduct a systematic literature review on urethral calculi in a contemporary cohort describing etiology,investigation,and management ***:A systematic search of MEDLINE and Cochrane Central Register of Controlled Trials(CENTRAL)databases was ***,including case reports and case series on urethral calculi published between January 2000 and December 2019,were ***-text manuscripts were reviewed for clinical parameters including symptomatology,etiology,medical history,investigations,treatment,and *** were collated and analyzed with univariate ***:Seventy-four publications met inclusion criteria,reporting on 95 *** symptoms(41.1%),pain(40.0%),and acute urinary retention(32.6%)were common presenting *** calculi were most often initially investigated using plain X-ray(63.2%),with almost all radio-opaque(98.3%).Urethral calculi were frequently associated with coexistent bladder or upper urinary tract calculi(16.8%)and underlying urethral pathology(53.7%)including diverticulum(33.7%)or stricture(13.7%).Urethral calculi were most commonly managed with external urethrolithotomy(31.6%),retrograde manipulation(22.1%),and endoscopic in situ lithotripsy(17.9%).Conclusion:This unique systematic review of urethral calculi provided a summary of clinical features and treatment trends with a suggested treatment *** in contemporary urological practice should be according to calculus size,shape,anatomical location,and presence of urethral pathology.

关键词： Urinary calculi Urethra Urethral calculi Management algorithm

The variation of DOM during long distance water transport by the China South to North Water Diversion Scheme and impact on drinking water treatment

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Frontiers of Environmental Science & Engineering 2024年第5期18卷 85-100页

作者： Hankun Yang Yujuan Li Hongyu Liu nigel J.D.Graham Xue Wu Jiawei Hou Mengjie Liu Wenyu Wang Wenzheng Yu State Key Laboratory of Environmental Aquatic Chemistry Key Laboratory of Drinking Water Science and TechnologyResearch Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing100085China School of Environment and Municipal Engineering Qingdao Technological UniversityQingdao266033China Colleges of Forestry Northeast Forestry UniversityHarbin150006China Department of Civil and Environmental Engineering Imperial College LondonSouth Kensington CampusLondonSW7 2AZUK School of Chemistry and Chemical Engineering Beijing Institute of TechnologyBeijing100081China State Key Laboratory of Separation Membrane Processes School of Environment Science and EngineeringTiangong UniversityTianjin300387China

In this study,samples were taken from three locations,upstream to downstream,along the central route project of the China South to North Water Diversion(SNWD)scheme in summer and *** were used to reveal the variations of dissolved organic matter(DOM)during the water transfer process,and the effects of these variations on drinking water treatment and disinfection by-products formation potential(DBPs-FP).The results showed that polysaccharides accumulate in summer and reduce in winter with flow distance,which has an important effect on the overall properties of DOM,as well as on the performance of coagulation,ultrafiltration,and the formation of *** substances,and their hydrophilic content,also increased in summer and decreased in winter with flow *** contrast,the concentration of small organic substances(MW≤1000 Da)increased in both summer and winter with flow distance,which affected both nanofiltration(NF)membrane fouling and *** results provide a useful case study of spatial and temporal changes in raw water DOM during long distance water transfer and their impact on the treatment and quality of drinking water from the SNWD.

关键词： Long-distance water transfer The China South to North Water Diversion Scheme Coagulation Membrane filtration Disinfection by-products

A machine learning driven 3D+1D model for efficient characterization of proton exchange membrane fuel cells

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Energy and AI

Energy and AI 2024年第3期17卷 281-294页

作者： Yuwei Pan Haijun Ruan Billy Wu Yagya N.Regmi Huizhi Wang nigel P.Brandon Department of Earth Science and Engineering Imperial College LondonLondon SW72AZUK Dyson School of Design Engineering Imperial College LondonLondon SW72AZUK Centre for E-Mobility and Clean Growth Coventry UniversityCoventry CV15FBUK Manchester Fuel Cell Innovation Centre Department of Natural SciencesManchester Metropolitan UniversityManchester M15GDUK Department of Mechanical Engineering Imperial College LondonLondon SW72AZUK

The computational demands of 3D continuum models for proton exchange membrane fuel cells remain substantial. One prevalent approach is the hierarchical model combining a 2D/3D flow field with a 1D sub-model for the catalyst layers and membrane. However, existing studies often simplify the 1D domain to a linearized 0D lumped model, potentially resulting in significant errors at high loads. In this study, we present a computationally efficient neural network driven 3D+1D model for proton exchange membrane fuel cells. The 3D sub-model captures transport in the gas channels and gas diffusion layers and is coupled with a 1D electrochemical sub-model for microporous layers, membrane, and catalyst layers. To reduce computational intensity of the full 1D description, a neural network surrogates the 1D electrochemical sub-model for coupling with the 3D domain. Trained by model-generated large synthetic datasets, the neural network achieves root mean square errors of less than 0.2%. The model is validated against experimental results under various relative humidities. It is then employed to investigate the nonlinear distribution of internal states under different operating conditions. With the neural network operating at 0.5% of the computing cost of the 1D sub-model, the hybrid model preserves a detailed and nonlinear representation of the internal fuel cell states while maintaining computational costs comparable to conventional 3D+0D models. The presented hybrid data-driven and physical modeling framework offers high accuracy and computing speed across a broad spectrum of operating conditions, potentially aiding the rapid optimization of both the membrane electrode assembly and the gas channel geometry.

关键词： Proton exchange membrane fuel cell Hierarchical model Neural network Hybrid model