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Coastal morphological modeling to assess the dynamics of Arklow Bank, Ireland

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International Journal of Sediment Research 2009年第3期24卷 299-314页

作者： J. K. PANIGRAHI P. N. ANANTH P. A. UMESH Senior engineering consultant L & T-RAMBOLL Consulting Engineers Limited Senior Project consultant L & T-RAMBOLL engineering consultant L & T-RAMBOLL

A numerical modeling and simulation experiment is carried out to assess the sediment dynamics of Arklow Bank, Ireland. To meet a requirement for favorable site selection to establish windmills on the bank, the long-term morphological changes of the coast are studied using the CAMS (Coastal Area Morphological Shell) model of the Mike-21 suite of programs. The morphological modeling of the bank was accomplished by pursuing a probabilistic approach for the observed tide and wave characteristics that contribute significantly to the sediment transport processes over the bank. A series of simulations are performed using Mike-21 NSW (Nearshore Spectral Wind-Wave), HD (Hydrodynamic), and ST (Sand Transport) models to establish the coastal hydraulics parameters. The results of the morphological modeling showed that generally the bank is dynamically stable with most areas of the bank having average bed level changes on the order of ±8 cm/day.

关键词： Morphodynamics Sediment transport CAMS Bed-level change Sand banks

基于LCEM-GFEM方法爆炸载荷作用下含缺陷岩体损伤机理研究（英文）

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Journal of Central South University 2024年第2期 496-510页

作者：陈勇王应朋杨玉贵孙文凯孟宁康 State Key Laboratory for Fine Exploration and Intelligent Development of Coal Resources China University of Mining and Technology China Coal consultant International State Key Laboratory for Geomechanics and Deep Underground engineering China University of Mining and Technology

在爆破作业过程中，岩体缺陷对裂纹扩展具有显著影响。本研究基于全局有限元方法的局部黏结单元(LCEM-GFEM)方法构建数值模拟模型，研究爆破作用下含缺陷岩体的损伤演化和裂纹扩展模式。通过引入能量传递系数，定量分析了缺陷形态对应... 详细信息

在爆破作业过程中，岩体缺陷对裂纹扩展具有显著影响。本研究基于全局有限元方法的局部黏结单元(LCEM-GFEM)方法构建数值模拟模型，研究爆破作用下含缺陷岩体的损伤演化和裂纹扩展模式。通过引入能量传递系数，定量分析了缺陷形态对应力波传播和衰减的影响。结果表明，缺陷形态对岩体的损伤特性和裂纹扩展具有显著影响。随着平行缺陷夹角的增加，爆破诱发的裂缝与衍生裂缝的合并路径从缺陷末端转移到了缺陷中间，能量传递系数增加，分形维度减小。随着平行缺陷之间的水平距离增加，平行缺陷之间的裂缝数目和能量传递系数相应减少。随着垂直缺陷之间的垂直距离增加，穿过缺陷C的主水平裂缝长度增加，能量传递系数和分形维度也增加。研究结果可为受到爆破荷载作用下含缺陷岩体的损伤特征提供指导。

关键词：缺陷岩体 LCEM-GFEM方法裂纹扩展 Cohesive单元分形理论

Stabilized effects of L-S cement-mixed batter pile composite foundation for existed warm frozen soil subgrade

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Journal of Mountain Science 2023年第2期20卷 542-556页

作者： SUN Gao-chen YAO Gang ZHANG Jian-ming LI Bo LI Jun-qi LIAN Wei-ping WEI Yi School of Civil engineering Xi’an Shiyou UniversityXi’an 710065China China State Construction engineering Corporation AECOM consultant Co. Ltd.Lanzhou 730000China State Key Laboratory of Frozen Soil engineering Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China

In permafrost regions with warm frozen soil,subgrade thaw-collapse phenomenon commonly occurs,facing thaw collapse problems of the existed frozen soil subgrade,thus it is difficult to use traditional methods such as active cooling and passive protection technology to stabilize the existed warm frozen soil *** study derives a novel stabilizer method,a long-short(L-S)cement-mixed batter pile composite foundation to stabilize the existed warm frozen soil *** solve the thawcollapse problems in warm frozen soil subgrade,high water content and large compressibility characteristics were compared between soft soil and warm frozen *** analysis of heat conduction and numerical simulation of finite element model were used to study the freeze–thaw process and evaluate the stabilized effects of the L-S cement-mixed batter piles on the warm frozen soil foundation of the Qinghai-Tibet ***,the thaw process and mechanical properties of foundation and piles were analyzed by introducing the hydration heat factor in the thermodynamic control *** results indicate that the thawing displacement of the existed warm frozen soil subgrade was reduced owing to the“support”and“grasp”effects of the L-S cement-mixed batter piles on the surrounding *** composite ground formed by strengthening the warm frozen ground with batter piles could considerably improve the bearing capacity of the existed warm frozen ground,effectively restrain the deformation of the upper embankment,and improve the strength of the *** analysis can provide method for the construction design of cement mixing batter pile foundation in cold regions.

关键词： Warm frozen soil subgrade Thaw collapse Thermal disturbance Long-short cementmixed batter pile Existed frozen soil subgrade

Earthquake damage potential and critical scour depth of bridges exposed to flood and seismic hazards under lateral seismic loads

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Earthquake engineering and engineering Vibration 2015年第4期14卷 579-594页

作者： Shin-Tai Song Chun-Yao Wang Wen-Hsiu Huang Department of Civil engineering Chung-Hsing University Structural Design Department Giant Home Engineering and Consultant

Many bridges located in seismic hazard regions suffer from serious foundation exposure caused by riverbed scour. Loss of surrounding soil significantly reduces the lateral strength of pile foundations. When the scour depth exceeds a critical level, the strength of the foundation is insufficient to withstand the imposed seismic demand, which induces the potential for unacceptable damage to the piles during an earthquake. This paper presents an analytical approach to assess the earthquake damage potential of bridges with foundation exposure and identify the critical scour depth that causes the seismic performance of a bridge to differ from the original design. The approach employs the well-accepted response spectrum analysis method to determine the maximum seismic response of a bridge. The damage potential of a bridge is assessed by comparing the imposed seismic demand with the strengths of the column and the foundation. The versatility of the analytical approach is illustrated with a numerical example and verified by the nonlinear finite element analysis. The analytical approach is also demonstrated to successfully determine the critical scour depth. Results highlight that relatively shallow scour depths can cause foundation damage during an earthquake, even for bridges designed to provide satisfactory seismic performance.

关键词： soil-structure interaction seismic analysis bridge pile foundation scour

Loss Factors and their Effect on Resonance Peaks in Mechanical Systems

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Sound & Vibration 2023年第1期57卷 1-13页

作者： Roman Vinokur Independent consultant Woodland HillsSan Diego91367USA

The loss factors and their effects on the magnitude and frequency of resonance peaks in various mechanical sys-tems are reviewed for acoustic,vibration,and vibration fatigue *** main trends and relationships were obtained for linear mechanical models with hysteresis *** well-known features(complex module of elasticity,total loss factor,etc.)are clarified for practical engineers and students,and new results are presented(in particular,for 2-DOF in-series models with hysteresis friction).The results are of both educational and prac-tical interest and may be applied for NVH analysis and testing,mechanical and aeromechanical design,and noise and vibration control in buildings.

关键词： Mechanical loss factor resonance peak acoustics vibration structural failure noise NVH engineering systems

Problems,assumptions and solutions in locomotive design,traction and operational studies

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Railway engineering Science 2022年第3期30卷 265-288页

作者： Maksym Spiryagin Qing Wu Oldrich Polach John Thorburn Wenhsi Chua Valentyn Spiryagin Sebastian Stichel Sundar Shrestha Esteban Bernal Sanjar Ahmad Colin Cole Tim McSweeney Centre for Railway engineering Central Queensland UniversityRockhampton 4702Australia Independent consultant Neuhausen am RheinfallSwitzerland Progress Rail NewcastleAustralia BHP Port HedlandAustralia engineering Centre for Railway Transport SkolkovoRussian Federation KTH Royal Institute of Technology StockholmSweden

Locomotive design is a highly complex task that requires the use of systems engineering that depends upon knowledge from a range of disciplines and is strongly oriented on how to design and manage complex systems that operate under a wide range of different train operational conditions on various types of *** that field investigation programs for locomotive operational scenarios involve high costs and cause disruption of train operations on real railway networks and given recent developments in the rollingstock compliance standards in Australia and overseas that allow the assessment of some aspects of rail vehicle behaviour through computer simulations,a great number of multidisciplinary research studies have been performed and these can contribute to further improvement of a locomotive design technique by increasing the amount of computer-based *** paper was focused on the presentation of the all-important key components required for locomotive studies,starting from developing a realistic locomotive design model,its validation and further applications for train *** integration of all engineering disciplines is achieved by means of advanced simulation approaches that can incorporate existing AC and DC locomotive designs,hybrid locomotive designs,full locomotive traction system models,rail friction processes,the application of simplified and exact wheel-rail contact theories,wheel-rail wear and rolling contact fatigue,train dynamic behaviour and intrain forces,comprehensive track infrastructure details,and the use of co-simulation and parallel *** cosimulation and parallel computing approaches that have been implemented on Central Queensland University’s High-Performance Computing cluster for locomotive studies will be *** confidence in these approaches is based on specific validation procedures that include a locomotive model acceptance procedure and field test *** problems and limitations presented in locomot

关键词： Locomotive Design Simulation Virtual prototyping Digital twin Traction Braking Wheel-rail wear Damage

Research e-infrastructures for open science: The national example of CSTCloud in China

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Data Intelligence 2023年第2期5卷 355-369页

作者： Lili Zhang Jianhui Li Paul F.Uhlir Liangming Wen Kaichao Wu Ze Luo Yude Liu Computer Network Information Center Chinese Academy of Sciences100190China consultant Information Policy and ManagementCallicoonNY12723USA

This paper focuses on research e-infrastructures in the open science *** analyze some of the challenges and opportunities of cloud-based science and introduce an example of a national solution in the China Science and Technology Cloud(CSTCloud).We selected three CSTCloud use cases in deploying open science modules,including scalable engineering in astronomical data management,integrated Earth-science resources for SDG-13 decision making,and the coupling of citizen science and artificial intelligence(AI)techniques in *** conclude with a forecast on the future development of research e-infrastructures and introduce the idea of the Global Open Science Cloud(GOSC).We hope this analysis can provide some insights into the future development of research e-infrastructures in support of open science.

关键词： Open science Open science cloud Research e-infrastructure Open science infrastructures Global Open Science Cloud Initiative

Numerical Simulation on a Tremendous Debris Flow Caused by Typhoon Morakot in the Jiaopu Stream,Taiwan

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Journal of Mountain Science 2014年第1期11卷 1-18页

作者： HSU Yu-chao YEN Haw TSENG Wen-hsiao JAN Chyan-deng Department of Hydraulic and Ocean engineering National Cheng Kung University Blackland Research and Extension Center Texas A&M AgriLife Research Sun-Rise engineering consultant Company

In August 2009,Typhoon Morakot brought a large amount of rainfall with both high intensity and long duration to a vast area of ***,this resulted in a catastrophic landslide in Hsiaolin Village,***,large amounts of landslides were formed in the Jiaopu Stream watershed near the southeast part of the Hsiaolin *** Hsiaolin Village access road(Provincial Highway No.21 and Bridge No.8) was completely destroyed by the landslide and consequent debris *** major scope of this study is to apply a debris flow model to simulate the disaster caused by the debris flow that occurred in the Jiaopu Stream during Typhoon *** to the interviews with local residents,this study applied the destruction time of Bridge No.8 and Chen's house to verify the numerical debris flow *** the spatial rainfall distributions information,the numerical simulations of the debris flow are conducted in two *** the first stage(before the landslide-dam failure),the elevation of the debris flow and the corresponding potential damages toward residential properties were *** the second stage(after the landslidedam failure),comparisons of simulation results between the longitudinal and cross profiles of the Jiaopu Stream were performed using topographic maps and satellite *** summary,applications of the adopted numerical debris flow model have shown positive impact on supporting better understanding of the occurrence and movement of debris flow processes.

关键词： Typhoon Morakot Debris flow Numerical simulation Jiaopu Stream Hsiaolin Village

PM2.5： global progress in controlling the motor vehicle contribution

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Frontiers of Environmental Science & engineering 2014年第1期8卷 1-17页

作者： Michael Patrick WALSH International consultant Arlington VA 22207 USA

It is well established that ambient particles in the size range of 2.5 microns or less case a wide variety of adverse health effects. According to a recent study from the World Health Organization, in 2010 these effects resulted in approximately 3.2million premature deaths with vehicles being one of the significant contributors. Diesel vehicle particulate emissions which are virtually all smaller than 2.5 microns raise additional special concerns due to their carcinogenicity and high ratio of black carbon （BC） to organic carbon; black carbon has recently been found to be the second most important contributor to climate change after carbon dioxide. Other pollutants emitted by diesels and other vehicles such as the oxides of nitrogen and volatile organic compounds also contribute to ambient particulate matter smaller than 2.5 microns in size （PM2.5） after undergoing secondary transformations in the atrno- sphere. Technologies have dramatically reduce vehicle been developed that can emissions when clean, low sulfur fuels are available and these technologies are being phased in throughout the industrialized world resulting in a global decrease in particulate matter （PM） and BC emissions from vehicles. However the vehicle population is growing rapidly in the developing world, leading to increases in emissions in many countries. Unless these rapidly industrializing countries move to state of the art vehicles and clean fuels, global PM, BC and NOx emissions from road vehicles will start to turn up over the next 10 to 15 years.

关键词： particulate black carbon climate change,diesels