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    题名 作者 年代 出处 被引量
1Fault plane parameters of Sanhe-Pinggu M8 earthquake in 1679 determined using present-day small earthquakes显示文摘The great Sanhe-Pinggu M8 earthquake occurred in 1679 was the largest surface rupture event recorded in history in the northern part of North China plain. This study determines the fault geometry of this earthquake by inverting seismological data of present-day moderate-small earthquakes in the focal area. We relocated those earthquakes with the double-difference method.Based on the assumption that clustered small earthquakes often occur in the vicinity of fault plane of large earthquake, and referring to the morphology of the long axis of the isoseismal line obtained by the predecessors, we selected a strip-shaped zone from the relocated earthquake catalog in the period from 1980 to 2009 to invert fault plane parameters of this earthquake. The inversion results are as follows: the strike is 38.23°, the dip angle is 82.54°,the slip angle is-156.08°, the fault length is about 80 km,the lower-boundary depth is about 23 km and the buried depth of upper boundary is about 3 km. This shows that the seismogenic fault is a NNE-trending normal dip-slip fault,southeast wall downward and northwest wall uplift, with the right-lateral strike-slip component. Moreover, the surface rupture zone, intensity distribution of the earthquake and seismic-wave velocity profile in the focal area all verified our study result.Xiaoshan Wang Xiangdong Feng Xiwei Xu Guiling Diao Yongge Wan Libin Wang Guangqing Ma 2014Earthquake Science2014,27,6:9
2Probing CENP-E function in chromosome dynamics using small molecule inhibitor syntelin显示文摘Xia Ding Feng Yan Phil Yao Zhihong Yang Weihong Wan Xiwei Wang Jing Liu Xinjiao Gao Ariane Abrieu Tongge Zhu Jiancun Zhang Zhen Dou Xuebiao Yao 2010Cell Research2010,20,12:8
3TST: Threshold Based Similarity Transitivity Method in Collaborative Filtering with Cloud Computing显示文摘Collaborative filtering solves information overload problem by presenting personalized content to individual users based on their interests, which has been extensively applied in real-world recommender systems. As a class of simple but efficient collaborative filtering method, similarity based approaches make predictions by finding users with similar taste or items that have been similarly chosen. However, as the number of users or items grows rapidly, the traditional approach is suffering from the data sparsity problem. Inaccurate similarities derived from the sparse user-item associations would generate the inaccurate neighborhood for each user or item. Consequently, its poor recommendation drives us to propose a Threshold based Similarity Transitivity (TST) method in this paper. TST firstly filters out those inaccurate similarities by setting an intersection threshold and then replaces them with the transitivity similarity. Besides, the TST method is designed to be scalable with MapReduce framework based on cloud computing platform. We evaluate our algorithm on the public data set MovieLens and a real-world data set from AppChina (an Android application market) with several well-known metrics including precision, recall, coverage, and popularity. The experimental results demonstrate that TST copes well with the tradeoff between quality and quantity of similarity by setting an appropriate threshold. Moreover, we can experimentally find the optimal threshold which will be smaller as the data set becomes sparser. The experimental results also show that TST significantly outperforms the traditional approach even when the data becomes sparser.Feng Xie Zhen Chen Hongfeng Xu Xiwei Feng Qi Hou 2013Tsinghua Science and Technology2013,18,3:7
4Influence of microwave treatment on mechanical behaviour of compact basalts under different confining pressures显示文摘The realisation of microwave-induced fracturing of hard rocks has potential signiflcance for microwave-assisted mechanical rock fracturing and stress release in deep rock masses.In this context,compact basalts were treated by microwave heating in a multi-mode cavity at a frequency of 2450 MHz,and then,we investigated the mechanical behaviour of basalt samples after microwave treatment under uniaxial compression and conventional triaxial compression(CTC)tests.After microwave exposure,cracks appeared on the surface and inside of the rock sample,and the temperature of the sample's surface was unevenly distributed.The results show that the conventional triaxial compressive strength(CTCS)of basalt samples decreased linearly with microwave exposure time,and the higher the confining pressure,the smaller the reduction in the strength of basalt samples after microwave treatment.Under uniaxial compression,microwave exposure greatly affected the axial deformation,suggesting that deformation resistance of the samples gradually decreases with increasing microwave exposure time.Under triaxial compression,some microcracks induced by microwave exposure closed due to the effect of confining pressure,resulting in the confining pressure inhibiting any rightward shift of the axial deformation curve.Furthermore,under uniaxial compression,the elastic modulus and Poisson's ratio of basalts also decreased in a quasi-linear manner with elapsed microwave exposure time.Under triaxial compression,microwave exposure has slight influence on elastic modulus and Poisson's ratio.After microwave treatment,the changes in rock strength and deformation mainly result from changes in between the mineral structures.Confining pressure results in the closure of microcracks produced by microwave exposure,so that effects of microwave treatment on strength and deformation decrease,thus reducing the influence on elastic constants.The cohesion decreases with increasing microwave exposure time and shows an approximately linear decrease over time.In the basalt samples,new microcracks in various directions generated by microwave exposure can increase the discreteness of test results,while the discreteness of test results caused by microcracks gradually reduces with increasing confining pressure.Gaoming Lu Xiating Feng Yuanhui Li Xiwei Zhang 2020Journal of Rock Mechanics and Geotechnical Engineering2020,12,2:7
5Cooperative geometric localization for a ground target based on the relative distances by multiple UAVs显示文摘Based on the locations of several unmanned aerial vehicles(UAVs) and their relative distances from a target, a ground target cooperative geometric localization method that is more effective than a traditional approach is proposed in this paper. First, an algorithm for determining the location of the target is described. The effectiveness and suitability of the proposed algorithm are then shown. Next, to investigate the location accuracy of the proposed method, the influence of three critical factors, namely, the flight altitude, UAV position errors, and measurement errors, is analyzed. Furthermore, for the required location accuracy, the feasible regions of these factors are determined based on their influence, and the location accuracy will satisfy the requirements if all factors are within the feasible regions. Finally, simulation results from the MATLAB/Simulink toolbox are presented to show the effectiveness of the proposed method and the availability of the feasible regions.Yaohong QU Feng ZHANG Xiwei WU Bing XIAO 2019Science China(Information Sciences)2019,62,1:3
6Recurrence of paleoearthquakes on the southeastern segment of the Ganzi-Yushu Fault,central Tibetan Plateau显示文摘Although there are many earthquake relics preserved in the southeast segment of the Ganzi-Yushu Fault in the central Tibetan Plateau,the recurrence regularity of paleoearthquakes is not yet clear.This work studies paleoearthquakes on this fault segment since the Holocene through geomorphic investigation and trench excavation.The results show that sinistral dislocation of the T3/T2 terrace boundary is up to 80 m at the Cuoa Township.A 1.5 m-high fault scarp extends 3 km near the Renguo Township.A number of paleoearthquakes are exposed in trenches at two places,respectively.In combination with historical records,our work has identified 5 or 6 paleoearthquakes on this fault segment since last 5600 years.The occurrence times and recurrence intervals of these paleoearthquakes are estimated by 14C dating on strata in the trenches.Our analysis shows that these paleoearthquakes do not exhibit evident periodicity,but instead show a clustering characteristic.From 5600 a to present,seismicity of the southeastern segment of the Ganzi-Yushu Fault has two active periods and one quiet period,and the present-day time is just in the second active epoch.The recurrence intervals of each active epoch are different:1000-1300 a in the first one,534 a in the second one.LI An SHI Feng YANG XiaoPing XU XiWei 2013Science China Earth Sciences2013,56,2:1
7Application of an incomplete landslide inventory, logistic regression model and its validation for landslide susceptibility mapping related to the May 12, 2008 Wenchuan earthquake of China显示文摘Chong Xu Xiwei Xu Fuchu Dai Zhide Wu Honglin He Feng Shi Xiyan Wu Suning Xu 2013Natural Hazards2013,,2:1
8Sedimentary and tectonic evolution of the Banquan pull-apart basin and implications for late Cenozoic dextral strike-slip movement of the Tanlu Fault Zone显示文摘The Banquan Basin is a pull-apart basin with the largest scale and the most prominent structure due to dextral slip of the Tanlu Fault Zone(TLFZ) in late Cenozoic. The depositional history of the basin records the start time and evolution of the right-lateral strike-slip movement of the TLFZ. This paper studies the sedimentary and tectonic evolution of the Banquan Basin by seismic reflection exploration, borehole detection and cosmogenic nuclide chronology. We analyze the coupling relationship between the pull-apart basin and the strike-slip fault and discuss the start time and tectonic significance of the right-lateral strikeslip of the TLFZ. Our study indicates that the Banquan Basin has undergone three evolutionary stages: weak rifting during the pre-pull-apart period, strong extension during the syn-pull-apart period and subsidence during the post-pull-apart period. This implies that the TLFZ, which controls the evolution of the basin, experienced an evolutionary process of weak activity,intensified activity and migration of activity toward the central basin. The sedimentary filling of the basin has strong response to the episodic pull-apart and extension of the basin. Lying upon the basement of the basin, a thin layer of Miocene mudstone slowly accumulated due to local rifting before the strong pull-apart event. Along with the dextral slipping and pull-apart process, the basin was filled with alluvial fan facies, fluvial facies and floodplain facies strata from bottom to top. The latest tectonic movement of the TLFZ in the North China Block in late Cenozoic was dominated by episodic dextral strike-slip motion, and this deformation pattern started at 4.01±1.27 Ma. The latest tectonic deformation in North China since late Cenozoic was governed by eastward extrusion and tectonic orogenesis of the eastern margin of the Qinghai-Xizang Plateau since late Miocene. The eastward thrusting of the Liupanshan fault zone and sinistral shearing of the Qinling fault zone led to the anticlockwise rotation and pushing of secondary blocks in North China, resulting in a planar bookshelf faulting and rotation pattern. This unique deformation pattern transferred eastwards to the North China Plain at ~4.01 Ma and the process continues to the present time.This planar bookshelf rotation, accompanied with regional sinistral strike-slip movement of the ~EW-trending boundary fault zones to the north and south of the North China Block and dextral strike-slip motion of the NNE-trending boundary faults between secondary blocks, is likely to be the long-range effect of the strong extrusion of the eastern margin of the QinghaiXizang Plateau.Peng SHU Xiwei XU Shaoying FENG Baojin LIU Kang LI Paul TAPPONNIER Xiaojuan DENG Guihua CHEN Nuan XIA Hongtai XU Jingjing QIN Fubing HE Yan MA Rongzhang ZHENG 2023Science China Earth Sciences2023,66,4:0
9Hybrid method based on flame volume concept for lean blowout limits prediction of aero engine combustors显示文摘The Lean Blowout(LBO)limit is crucial for the aircraft engines.The semi-empirical(such as Lefebvre’s LBO model and Flame Volume(FV)model),numerical and hybrid methods are widely utilized for the LBO limit quick prediction.An innovative hybrid method based on the FV concept is proposed.This method can be classified as a semi-empirical/physical based hybrid prediction method.In this hybrid method,it is assumed that the flame volume varies nearly linearly with the fuel/air ratio near the LBO.The flame volume is obtained directly by the numerical simulation using the threshold value of the visible flame boundary as 900 K.Then the final LBO limits is determined by the FV model.On the premise of keeping the good generality of prediction,the hybrid method based on the FV concept can further improve the prediction accuracy.The comparison with the prediction of the existing available methods on fifteen combustors shows that the hybrid method based on the FV concept achieves better prediction accuracy.The prediction uncertainties between the experimental results and the predicted values by the hybrid method based on the FV concept are within about±10%.Lei SUN Yong HUANG Xiwei WANG Zekun ZHENG Ruixiang WANG Xiang FENG 2021Chinese Journal of Aeronautics2021,34,5:0
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