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Intelligent identifi cation method for near-surface ground fi ssures based on seismic data

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Applied Geophysics 2020年第5期17卷 639-648,899页

作者： shi Su-Zhen gu jian-Ying Feng jian Duan Pei-fei Qi You-chao Han Qi State Key Laboratory for Coal Resources and Safety Mining China University of Mining and Technology(Beijing)Beijing 100083China College of Geoscience and Surveying Engineering China University of Mining Technology(Beijing)Beijing 100083China Zhongshui North Survey Design and Research Co.Ltd.

Taking a study area in Jinzhong Basin in Qixian County,Shanxi Province,as an example,this work performs an intelligent interpretation of ground *** the basis of a complete analysis of the regional geological background in the study area,dip-steering cube operation and median filtering of seismic data were performed using fast Fourier transform to improve the continuity of seismic events and eliminate random noise.A total of 200 stratigraphic continuous sample training points and 500 discontinuous training points were obtained from the processed seismic ***,a variety of attributes(coherence,curvature,amplitude,frequency,etc.)were extracted as the input for the multilayer perceptron neural network *** the training period,the training results were traced by normalized root mean square error(RMSE)and misclassifi *** training results showed a downward trend during the training *** misclassifi cation curve was stable at 0.3,and the normalized RMSE curve was stable at *** the value of the normalized RMSE curve reached the minimum,the training was terminated,and the training results were extended to the whole data volume to obtain the attribute cube of intelligent ground fi ssure *** characteristics of ground fi ssures were analyzed and identifi ed from the sections and slices.A total of 11 ground fissures were finally *** interpretation results showed that the dip angles were 60°-85°,the fault throws were 0-43 m,and the extension lengths were 300-1,100 m in the whole *** strike of 73%of the ground fi ssures was consistent with the direction of the regional tectonic *** cally,four ground fi ssures coincided with the surface disclosed,and the verifi cation rate reached 100%.In conclusion,the intelligent ground fi ssure detection attribute based on the dip-steering cube is eff ective in predicting the spatial distribution of ground fi ssures.

关键词： neural network ground fi ssures development area dip-steering cube intelligent ground fi ssure detection attribute

First-principles study of the co-effect of carbon doping and oxygen vacancies in ZnO photocatalyst

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Chinese Physics B 2021年第2期30卷 419-425页

作者： Jia shi Lei Wang Qiang gu Department of Physics University of Science and Technology BeijingBeijing 100083China

Although tuning band structure of optoelectronic semiconductor-based materials by means of doping single defect is an important approach for potential photocatalysis application,C-doping or oxygen vacancy(Vo)as a single defect in ZnO still has limitations for photocatalytic ***,the influence of co-existence of various defects in ZnO still lacks sufficient ***,we investigate the photocatalytic properties of ZnOx C0.0625(x=0.9375,0.875,0.8125),confirming that the co-effect of various defects has a greater enhancement for photocatalytic activity driven by visible-light than the single defect in *** clarify the underlying mechanism of co-existence of various defects in ZnO,we perform systematically the electronic properties calculations using density functional *** is found that the coeffect of C-doping and Vo in ZnO can achieve a more controllable band gap than doping solely in ***,the impact of the effective masses of ZnO_(x)C_(0.0625)(x=0.9375,0.875,0.8125)is also taken into *** comparison with heavy Vo concentrations,the light Vo concentration(x=0.875)as the optimal component together with C-doping in ZnO,can significantly improve the visible-light absorption and benefit photocatalytic activity.

关键词： first-principles theory electron density of states and band structure of crystalline solids Ⅲ-ⅤandⅡ-Ⅵsemiconductors

Tau in Alzheimer’s Disease:Pathological Alterations and an Attractive Therapeutic Target

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Current Medical Science 2020年第6期40卷 1009-1021页

作者： jian-lan gu Fei LIU Department of Biochemistry and Molecular Biology School of MedicineNantong UniversityNantong 226001China Key Laboratory of Neuroregeneration and Ministry of Education of jiangsu Co-innovation Center of NeuroregenerationNantong 226001China Department of Neurochemistry Inge Grundke-Iqbal Research FloorNew York State Institute for Basic Research in Developmental DisabilitiesStaten IslandNY 10314USA

Alzheimer’s disease(AD)is an age-related neurodegenerative disease with two major hallmarks:extracellular amyloid plaques made of amyloid-β(Aβ)and intracellular neurofibrillary tangles(NFTs)of abnormally hyperphosphorylated *** number of NFTs correlates positively with the severity of dementia in AD ***,there is still no efficient therapy available for AD treatment and prevention so far.A deeper understanding of AD pathogenesis has identified novel strategies for the generation of specific therapies over the past few *** studies have suggested that the prion-like seeding and spreading of tau pathology in the brain may be a key driver of *** protein is considered as a promising candidate target for the development of therapeutic interventions due to its considerable pathological role in a variety of neurodegenerative *** tau hyperphosphorylation plays a detrimental pathological role,eventually leading to *** the present review,we describe the recent research progresses in the pathological mechanisms of tau protein in AD and briefly discuss tau-based therapeutic strategies.

关键词： Alzheimer’s disease tau protein hyperphosphorylation propagation of tau pathology

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高压泡沫涨裂破岩特性试验研究

岩土工程学报 2025年第1期47卷 125-134页

作者：刘送永崔松顾聪聪中国矿业大学机电工程学院江苏徐州221116 中国矿业大学智能采矿装备技术全国重点实验室江苏徐州221116 安徽理工大学机电工程学院安徽淮南232001

针对钻爆法和机械法在岩石破碎工程中的弊端,基于泡沫的高黏性和可压缩性,提出了高压泡沫涨裂破岩技术。首先设计高压泡沫涨裂破岩装置,理论分析高压泡沫瞬间释放冲击岩石涨裂孔过程,搭建高压泡沫涨裂力测试装置并开展涨裂力影响试验,... 详细信息

针对钻爆法和机械法在岩石破碎工程中的弊端,基于泡沫的高黏性和可压缩性,提出了高压泡沫涨裂破岩技术。首先设计高压泡沫涨裂破岩装置,理论分析高压泡沫瞬间释放冲击岩石涨裂孔过程,搭建高压泡沫涨裂力测试装置并开展涨裂力影响试验,建立高压泡沫涨裂破岩试验系统,探讨不同空气体积分数时的泡沫涨裂特性,揭示高压泡沫涨裂破岩机理。研究表明:高压泡沫释放时,能够在涨裂孔内产生比泡沫初始压力更高的涨裂力,但涨裂力随泡沫空气体积分数增加而先增大后减小,高压泡沫涨裂破岩经历了裂纹初生、裂纹扩展、涨裂抛掷、涨裂结束4个阶段,破岩重量随泡沫空气体积分数的增加而先增大后减小,当空气体积分数为60%时,由高压泡沫冲击涨裂孔产生的压应力波在岩石上表面反射形成的拉应力造成岩石破坏形式为涨裂坑,空气体积分数为70%~90%时,泡沫涨裂形式为大块岩石分离,这主要是由孔底直角处应力集中效应造成。

关键词：高压泡沫涨裂破岩裂纹扩展涨裂力

Dynamical characteristics of geomorphologic evolution of the basins covered by Pisha-sandstone in the eastern wing of the Ordos Plateau, China

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Journal of Mountain Science 2018年第5期15卷 1046-1056页

作者： gu Zhen-kui shi Chang-xing Key Laboratory of Water Cycle and Related Land Surface Processes Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China University of Chinese Academy of Sciences Beijing 100049 China

There are several basins with high sediment yield in the Pisha-sandstone covering area of the east wing of the Ordos Plateau. Due to the lack of targeted research on the dynamical characteristics of geomorphic evolution that plays an important role in the sand production, this paper analyzed the tectonic activity intensity and erosion characteristics of the area. The results show that the intensity of tectonic activities in the area is generally moderateweak and shows an unconspicuous increase from north to south. Tectonic activity is manifested mainly in the form of uplift. The uplift rate in the lower reaches of each basin is greater than the erosion rate,which is prominent in the Kuyehe and the Tuweihe rivers. During the uplift of the regional topography,the most serious parts under erosion are generally concentrated in the upstream and midstream of basins. All longitudinal profiles of the basins have a shape close to an exponential function, which indicates that they are in the early stage of erosion evolution. The mechanisms of geomorphologic evolution of these basins have a great similarity. The conservative estimate of historical average erosion rate was less than 182–520 t/(km^2·yr), much less than that of the modern times. The average stream power values are typically distributed between 4 and102 W/m, with the larger being in the Kuyehe and the Tuweihe rivers and the smallest being in the Qinshuihe River. The maximum stream power value appears in the downstream reach, which should be the main reason for the particles being directly injected into the Yellow River. From the perspective of geomorphological evolution, the current soil and water conservation measures can hardly cure the erosion of these basins in the long run.

关键词： Dynamic characteristics Geomorphologic evolution Ordos Plateau Tectonicactivity Stream power Geomorphological parameter

On the correction of the boundary deficiency in SPH for the frictional contact simulation

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Science China(Technological Sciences) 2014年第1期57卷 86-100页

作者： WANG jian HUA Hui gu Chongshi National Engineering Research Center of Water Resources Efficient Utilization and Engineering Safety Hohai University College of Water Conservancy and Hydropower Engineering Hohai University

Smoothed particle hydrodynamics(SPH)is a mesh-free method which is powerful for large deformation computation of ***,the algorithm for the simulation of frictional contact which is common in geotechnical engineering is still quite immature due to the boundary *** this study,the cause of boundary deficiency in the SPH simulation for frictional contact is ***,based on mathematical derivation,the method to correct boundary deficiency related to frictional contact is discussed theoretically,where the frictional contact algorithm is established by dividing the computational domain into several subdomains according to the existing contact boundaries and by using contact forces as bridges of these subdomains to fulfil problem solving,and the value of correction coefficient is obtained by comparing the SPH outcome of the contact particles with that calculated through Newton’s second law of *** the same time,from the perspective of numerical computation,an optimized value for the correction coefficient is proposed,and a thorough investigation is performed on the cubic spline kernel function and quintic spline kernel function,whose correction coefficients are found to be 2.0 and[2.0,2.16],***,numerical tests are carried out to verify the proposed *** outcome of the study is helpful to providing theoretical support for the research of frictional contact simulation within the framework of SPH.

关键词： smoothed particle hydrodynamics (SPH) frictional contact boundary deficiency correction

2D VARIABLE FACTOR LEARNING CONTROLLER AND ITS APPLICATION IN PNEUMATIC SERVO SYSTEM

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Chinese Journal of Mechanical Engineering 1998年第4期11卷 24-29页

作者： Lu, Lu gu, Yiming shi, Weixiang Xi'an Jiaotong Univ Xi'an China

A new learning control law is presented which can obtain learning gain matrices from a recursive identifier along the learning axis. The system convergence is proved when disturbances exist in the system. Finally it i... 详细信息

关键词： Learning control Convergence Pneumatic servo system

Correlation Between Magnetovolume and Colossal Magnetoresistance Effects in Terbium Doped La-Sr-Mn-O Perovskite

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Chinese Physics Letters 2000年第5期17卷 373-375页

作者： WU jian ZHANG shi-Yuan YIN shi-Long CAO Qing-Qi gu Kun-Ming DU You-Wei Mathematics and Physics Department Hohai UniversityNanjing 210098 National Laboratory of Solid State Microstructure Physics and Department of Physics Nanjing UniversityNanjing 210093

(La_(0.67)Tb_(0.33))_(2/3)Sr_(1/3)MnO_(3) has been studied in order to probe mechanisms responsible for the giant magnetore-sistonce ratios and the lattice effect in this kind of *** experiment has shown a strong connection between the magnetotransport and magnetovolume *** applied magnetic Geld not only gives rise to a large negative magnetoresistance(-900%)but also produces two different magnetovolume effects which reflect two different magnetostriction mechanisms in the compound.

关键词： properties. compound. magnetoresistance

Injury-induced rapid activation of MAPK signaling in dechorionated eggs and larvae of the silkworm Bombyx mori

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Insect Science 2017年第2期24卷 248-258页

作者： shi-Hong gu Chien-Hung Chen Department of Biology National Museum of Natural Science Taichung Taiwan China Chung Hwa University of Medical Technol-ogy Tainan County Taiwan China

Previous study showed that diapause in Bombyx mori eggs can be ter- minated by dechorionation and that activation in the mitogen-activated protein kinase （MAPK）/extracellular signal-regulated kinase （ERK） in dechorionated cultured eggs is involved in diapause termination. In the present study, the possible mechanism underlying activation of ERK upon dechorionation was further investigated. Results showed that me- chanical injury of diapause eggs without medium incubation also resulted in rapid increase in the phospho-ERK levels and that injury increased the phospho-ERK levels at different stages of both diapause eggs and eggs in which diapause initiation was prevented by HC1. Effects of anaerobiosis on dechorionation-stimulated phospho-ERK levels showed that the mechanical injury itself but not the dramatic increase in oxygen uptake upon injury is in- volved in a rapid activation of ERK. Chemical anaerobiosis on dechorionation-stimulated phospho-ERK levels and the in vivo effect of anaerobiosis showed that the supply of oxygen also plays a role in ERK signaling. In addition, injury induced the phosphory- lation of c-jun N-terminal kinases （JNKs） and p38 kinase, components of two parallel MAPK pathways. A kinase assay showed a dramatic increase in .INK kinase activity in egg lysates upon injury. When newly hatched first instar larvae were injured, an increase in the phospho-ERK levels similar to that in dechorionated eggs was observed. From the results, we hypothesize that the injury-induced rapid activation of MAPK signaling, which serves as a natural signal for embryonic development, is related to diapause termination in dechorionated eggs.

关键词： Bombyx mori dechorionation embryonic diapause ERK phosphorylation injury MAPK