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Reflection-based traveltime and waveform inversion with second-order optimization

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Petroleum Science 2022年第4期19卷 1582-1591页

作者： teng-fei wang Jiu-Bing Cheng Jian-Hua Geng State Key Laboratory of Marine Geology Tongji UniversityShanghai200092China School of Ocean and Earth Science Tongji UniversityShanghai200092China

Reflection-based inversion that aims to reconstruct the low-to-intermediate wavenumbers of the subsurface model, can be a complementary to refraction-data-driven full-waveform inversion(FWI), especially for the deep target area where diving waves cannot be acquired at the surface. Nevertheless, as a typical nonlinear inverse problem, reflection waveform inversion may easily suffer from the cycleskipping issue and have a slow convergence rate, if gradient-based first-order optimization methods are used. To improve the accuracy and convergence rate, we introduce the Hessian operator into reflection traveltime inversion(RTI) and reflection waveform inversion(RWI) in the framework of second-order optimization. A practical two-stage workflow is proposed to build the velocity model, in which Gauss-Newton RTI is first applied to mitigate the cycle-skipping problem and then Gauss-Newton RWI is employed to enhance the model resolution. To make the Gauss-Newton iterations more efficiently and robustly for large-scale applications, we introduce proper preconditioning for the Hessian matrix and design appropriate strategies to reduce the computational costs. The example of a real dataset from East China Sea demonstrates that the cascaded Hessian-based RTI and RWI have good potential to improve velocity model building and seismic imaging, especially for the deep targets.

关键词： Reflection waveform inversion Reflection traveltime inversion Gauss-Newton Hessian

Shaking table tests on a cantilever retaining wall with reinforced and unreinforced backfill

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2022年第11期23卷 900-916页

作者： Ming WEI Qiang LUO Gui-shuai FENG teng-fei wang Liang-wei JIANG School of Civil Engineering Southwest Jiaotong UniversityChengdu 610031China MOE Key Laboratory of High-Speed Railway Engineering Chengdu 610031China

Physical modelling of cantilever retaining walls with and without backfill reinforcement was conducted on a 1g shaking table to evaluate the mitigation effect of reinforcement on system dynamics(g denotes the acceleration of gravity).The model wall has a height of 1.5 m with a scale ratio of 1/4 and retains dry sand throughout.The input motions are amplified to three levels of input peak base acceleration,0.11g,0.24g,and 0.39g,corresponding to minor,moderate,and major earthquakes,respectively.Investigation of the seismic response of the retaining walls focuses on acceleration and lateral displacement of the wall and backfill,dynamic earth pressures,and tensile load in the reinforcements(modeled by phosphor-bronze strips welded into a mesh).The inclusion of reinforcement has been observed to improve the integrity of the wall-soil system,mitigate vibration-related damage,and reduce the fundamental frequency of a reinforced system.Propagation of acceleration from the base to the upper portion is accompanied by time delay and nonlinear amplification.A reinforced system with a lower acceleration amplification factor than the unreinforced one indicates that reinforcement can reduce the amplification effect of input motion.Under minor and moderate earthquake loadings,reinforcement allows the inertia force and seismic earth pressure to be asynchronous and decreases the seismic earth pressure when inertia forces peak.During major earthquake loading,the wall is displaced horizontally less than the backfill,with soil pushing the wall substantially;the effect of backfill reinforcement has not been fully mobilized.The dynamic earth pressure is large at the top and diminishes toward the bottom.

关键词： Cantilever retaining wall Backfill reinforcement Seismic response Shaking table test Dynamic earth pressure Phase shift

pH-dependent corrosion initiation behavior induced by inclusions of low alloy steel in simulated marine environments

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Journal of Iron and Steel Research(International) 2023年第10期30卷 2067-2079页

作者： Heng Ma Zhong-xue wang Yue Liu Yue-xiang wang teng-fei wang Qing-pu Zhang Zhong-yu Cui Yinshan Section Steel Corporation of Laiwu Steel Group Ltd. Jinan 271104ShandongChina School of Materials Science and Engineering Ocean University of ChinaQingdao 266100ShandongChina

The initial pitting corrosion behavior triggered by inclusions in S420 low alloy steel in acidic artificial seawater(ASW)and weak-alkaline ASW was characterized.The geometric data of the corrosion pits formed in the ASW with different pH were calculated.The pH of the ASW has an obvious influence on the pit shape.The pits in acidic ASW exhibit a funnel shape,while those in weak-alkaline ASW present a cone shape with a larger pit volume.The reason for the difference in the morphology and size of the corrosion pits induced by inclusion is that it is easier to trigger micro-galvanic corrosion in different structures and different areas of the pits in the acidic environment.

关键词： Low alloy steel Inclusion Pitting corrosion Micro-galvanic corrosion

Processes and causes of Phanerozoic tectonic evolution of the western Tarim Basin,northwest China

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Petroleum Science 2020年第2期17卷 279-291页

作者： teng-fei wang Zhen-Kui Jin He Li Dong-Qing Liu Ri-Hui Cheng Shu-Ting Shi Jin-Yi wang Faculty of Land Resources Engineering Kunming University of Science and TechnologyKunming 650093China College of Geosciences China University of Petroleum(Beijing)Beijing 102249China College of Earth Sciences Jilin UniversityChangchun 130061JilinChina Geological Research Center Bureau of Geophysical ProspectingZhuozhou 072751HebeiChina Shenzhen Branch of CNOOC China Limited Shenzhen 518000GuangdongChina

This paper addresses the Phanerozoic tectonic evolution of the western Tarim Basin based on an integrated stratigraphic,structural and tectonic analysis.P-wave velocity data show that the basin has a stable and rigid basement.The western Tarim Basin experienced a complex tectonic evolutionary history,and this evolution can be divided into six stages:Neoproterozoic to Early Ordovician,Middle Ordovician to Middle Devonian,Late Devonian to Permian,Triassic,Jurassic to Cretaceous and Paleogene to Quaternary.The western Tarim Basin was a rift basin in the Neoproterozoic to Early Ordovician.From the Middle Ordovician to Middle Devonian,the basin consisted of a flexural depression in the south and a depression that changed from a rift depression to a flexural depression in the north during each period,i.e.,the Middle-Late Ordovician and the Silurian to Middle Devonian.During the Late Devonian to Permian,the basin was a depression basin early and then changed into a flexural basin late in each period,i.e.,the Late Devonian to Carboniferous and the Permian.In the Triassic,the basin was a foreland basin,and from the Jurassic to Cretaceous,it was a downwarped basin.After the Paleogene,the basin became a rejuvenated foreland basin.Based on two cross sections,we conclude that the extension and shortening in the profile reflect the tectonic evolution of the Tarim Basin.The Tarim Basin has become a composite and superimposed sedimentary basin because of its long-term and complicated tectonic evolutionary history,highly rigid and stable basement and large size.

关键词： Western Tarim Basin Phanerozoic Structural evolution Composite and superimposed sedimentary basin

Changes in climate extremes in a typical glacierized region in central Eastern Tianshan Mountains and their relationship with observed glacier mass balance

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Advances in Climate Change Research 2022年第6期13卷 909-922页

作者： Hui ZHANG fei-teng wang Ping ZHOU Altai Observation and Research Station of Cryospheric Science and Sustainable Development State Key Laboratory of Cryospheric ScienceNorthwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China Tianshan Glaciological Station State Key Laboratory of Cryospheric ScienceNorthwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China

As an icon of anthropogenic climate change,alpine glaciers are highly sensitive to climate change.However,there remain research gaps regarding trends in climate extremes in glacierized regions and their relationship with local glacier mass balance.In this study,these relationships and their underlying links were explored in a typical glacierized region in the Eastern Tianshan Mountains,China,from 1959 to 2018.All warm extremes exhibited increasing trends that intensified dramatically from the 1990s.Meanwhile,decreasing trends were found for all cold extremes except for the temperatures of the coldest days and coldest nights.All of the precipitation extremes demonstrated increasing trends,except for consecutive dry days and consecutive wet days.Statistically significant positive/negative correlations were detected between glacier mass balance and six warm extremes(TN90p,TX90p,SU99p,TR95p,TXx,and TNx)/four cold extremes(TN10p,TX10p,FD0,and ID0).Simulation results showed that the impact of the intensity/frequency of the warm extremes(TN90p,TX90p,SU99p,and TR95p)on glacier ablation was remarkable and the effect of the cold extremes(FD0 and ID0)on accumulation was also significant.Additionally,the increases in the intensity and frequency of most climate extremes seemed more remarkable in glacierized regions than in non-glacierized regions.Hence,studies on glacier-climate interactions should focus greater attention on the impacts of climate extremes on glacier evolution.

关键词： Climate extremes Typical glacierized region Glacier mass balance Eastern tianshan mountains

Scrutinise the variations of glaciers and their climatic attributions in the Sanjiangyuan National Park during 1969-2018

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Advances in Climate Change Research 2022年第4期13卷 531-539页

作者： Lin wang Yan-Qun BI fei-teng wang Chang-Bin BAI Jing MING State Key Laboratory of Cryospheric Sciences Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China Beacon Science&Consulting Malvern SA 5061Australia

Since 2020,the first national park of China,the Sanjiangyuan National Park(Park)has been put into operation in China.This Park is one of the most vulnerable regions to the rapid climate change in the Tibetan Plateau.There have not been any investigations into the current status of the glacier resources in the Park so far.This study reported the first summary of the glaciers in the Park at present and their variations since the 1960s.The data used here come from the two Chinese Glacier Inventories finished during 1969-1970 and 2006-2010,respectively,and the remote-sensing images during 1985-1990,1995-2000 and 2018.The total glacier area in the Park is 772 km^(2)to our best estimate,much less than 2342 km^(2)reported in the first Chinese Glacier Inventory published in 2009.The shrinkage rate of the glaciers in the Yangtze River Park(a sub-park)had slowed from-0.37%per year during the 1970s to-0.09%per year during 2002-2012 in area,while that in the Lancang River Park had sped up from-0.34%per year during 1968-2000 to-0.67%per year during 2000-2018.There are no glaciers in the Yellow River Park(a sub-park).The change in the glaciers was related to the regional relatively rapidly warming and insufficient mass supply from precipitation.The geographic features of the glaciers in the Yangtze and Lancang Parks also lead to their different change extents,most of which happened at 5500 m a.***.l.and below.

关键词： Sanjiangyuan National Park Tibetan Plateau Glaciers Remote sensing Climate change Geographic features

季节性冻土区光伏支架螺旋桩抗冻拔试验研究（英文）

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2016年第7期17卷 512-524页

作者： teng-fei wang Jian-kun LIU Hua-gang ZHAO Ya-long SHANG Xiao-qiang LIU School of Civil Engineering Beijing Jiaotong University North China Power Engineering Co. Ltd.of China Power Engineering Consulting Group

目的:基于相似性原理,模拟实际工况中的降温冻结过程;通过室内试验确定最优桩型,并推导冻拔量与冻深的定量关系。创新点:1.进行季节性冻土区螺旋桩的自由冻胀试验;2.根据相似性原理,在室内试验过程中调整冷端温度与几何尺寸以缩短冻结时... 详细信息

目的:基于相似性原理,模拟实际工况中的降温冻结过程;通过室内试验确定最优桩型,并推导冻拔量与冻深的定量关系。创新点:1.进行季节性冻土区螺旋桩的自由冻胀试验;2.根据相似性原理,在室内试验过程中调整冷端温度与几何尺寸以缩短冻结时间;3.推导得到6种桩型冻拔量与冻结深度的定量关系。方法:1.通过相似性原理确定试验条件,模拟实际工况中的降温冻结过程;2.观测此过程中5种螺旋桩型的温度场、冻拔量和土压力随时间的变化规律,并设置一组光滑桩作为对比;3.根据冻拔量大小选取最优桩型,并推导冻拔量与冻深的定量关系。结论:1.螺旋桩冻拔量小于光滑桩,验证了螺旋桩抗冻拔的有效性;采用不同土样有相同规律。2.冻深达到0.9 m的季冻区,双螺旋大叶片桩抗冻拔效果最好;螺旋叶片建议设置在非冻区;冻拔量大小关系为:双螺旋大叶片桩<半螺旋大叶片桩<半螺旋小叶片桩<双螺旋小叶片桩<全螺旋桩<光滑桩。3.得到6种桩型冻拔量与冻深的线性关系。4.土中水开始冻结时土压力增大,含冰量稳定后土压力变化很小。

关键词：季节性冻土区螺旋桩冻胀相似性原理冻拔

Rapid mass loss and disappearance of summer-accumulation type hanging glacier

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Advances in Climate Change Research 2022年第1期13卷 73-81页

作者： Chun-Hai XU Zhong-Qin LI fei-teng wang Pu-Yu wang Jian-Xin MU State Key Laboratory of Cryospheric Science Northwest Institute of Eco-Environment and ResourcesChinese Academy of Sciences.Lanzhou730000China National Cryosphere Desert Data Center Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China

Hanging glaciers hold the absolute dominant number in West China and their changes had important influences on local hydrology,sea-level rise and natural hazards(snow/ice avalanches).However,logistic and operational difficulties have resulted in the lack of in-situ-measured data,leaving us with poor knowledge of the changing behaviors of this type of glacier.Here,we presented the spatiotemporal pattern of seasonal and annual mass changes of a mid-latitude hanging glacier in the Tien Shan based on repeated terrestrial laser scanning(TLS)surveys during the period 2016-2018.The distributed glacier surface elevation changes exhibited highly spatiotemporal variability,and the winter elevation changes showed slight surface lowering at the upper elevations and weak thickening at the glacier terminus,which was contrary to altitudinal elevation changing patterns at the summer and annual scales.Mass balance processes of the hanging glacier mainly occurred during summer and the winter mass balance was nearly balanced(-0.10±0.15 m w.e.).The glacier exhibited more rapid mass loss than adjacent other morphological glacier and the estimated response time of the glacier to climate change was very short(6-9 years),indicating hanging glaciers will experience rapid wastage and disappearance in the future even with climate change mitigation.

关键词： Hanging glaciers Mass balance processes Glacier disappearance Tien Shan Climate change

Dark NoC: Hurdling the Power and Temperature Budgets from Communication Perspective

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Journal of Electronic Science and Technology 2014年第4期12卷 346-353页

作者： teng-fei wang Wen-Ming Pan Bao-Xin Zhao Guangzhou Institute of Advanced Technology Chinese Academy of Sciences

Among the components on a many-core chip, network-on-chip （NoC） has already contributed a large portion to overall power consumption. Optimizing NoC performance under a given power budget is further complicated to keep the network connectivity and minimize the detour distances. In this paper, a NoC power budgeting method from the communication perspective is proposed, which intelligently powers off routers/iinks and sets up alternative paths to restrict the power and thermal envelop. The effect of performance optimizaion of the proposed power budgeting mothod is measured based on latency and in the given power budget, 22% latency can be reduced averagely compared with some competing methods when running real benchmarks.

关键词： Terms--Alternative path configurableswitches dark network-on-chip hotspot migration.