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Load transfer laws of tensile anchors in rock masses with weak interlayers based on a shear-slipping updating model

Journal of Mountain Science 2022年第3期19卷 812-825页

作者： WANG Yan XIANG Xin LI Chang-dong ZHU Guo-qiang SONG Cheng-bin XIAN Jin-ye zhang jia-jun Faculty of Engineering China University of GeosciencesWuhan 430074China China Three Gorges Corporation Limited Beijing 100038China Three Gorges Research Center for Geo-hazards Ministry of Education China University of GeosciencesWuhan 430074China

The load transfer characteristics of a tensile anchor in the rock mass with weak interlayers were investigated,considering the nonuniform stress of the horizontally layered rock mass along *** improved shear-slipping model was proposed to describe the stress evolution characteristics of the bolt-rock *** on the improved model,analytical solutions of the axial force,shear stress distribution and load-displacement relationship considering the residual stress stage were *** effects of the stratigraphic sequence,pulling force and bolt diameter on the stress distribution of the anchorage interface were evaluated by using analytical *** results were verified by applying the finite difference numerical simulation *** sensitivity of each parameter to the axial force and shear stress of the rock bolt was determined based on calculation of the sensitivity *** study results show that the axial force and shear stress tend to decrease nonuniformly along the rock bolt towards the anchorage *** to the existence of weak interlayers,the shear stress mutates at the weak and hard rock interface,and the axial force appears to“rebound”at the bottom of the anchored *** has more significant effects on the axial force and shear stress at the bottom of the anchor than at the top of the *** pulling force is more sensitive to the anchor stress than stratigraphic sequence when the bolt diameter is *** study provides a theoretical framework for the fundamental problem of tensile bolts in horizontally or vertically laminated rock masses,providing a theoretical basis for anchor design.

关键词： Weak interlayer Tensile anchor Residual stress Shear-slipping updating model Sensitivity

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武汉地铁8号线引入华侨城方案研究

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铁道工程学报 2013年第2期30卷 94-98页

作者：张嘉峻中铁第四勘察设计院集团有限公司武汉430063

研究目的:城市的发展能为轨道交通工程带来充足的客流,提高地铁的价值,实现地铁工程与城市发展的良性循环。根据《武汉市城市快速轨道交通建设规划》的要求,地铁8号线需引入规划华侨城,华侨城紧临东湖风景区,是8号线主方向的突变点,8号... 详细信息

研究目的:城市的发展能为轨道交通工程带来充足的客流,提高地铁的价值,实现地铁工程与城市发展的良性循环。根据《武汉市城市快速轨道交通建设规划》的要求,地铁8号线需引入规划华侨城,华侨城紧临东湖风景区,是8号线主方向的突变点,8号线与华侨城结合困难,为了引入华侨城,在东湖区域形成了绕圈现象,增加了工程规模,对东湖风景区形成较大的影响。研究结论:通过现状调查、分析原因,并针对主要原因制订对策及进行对策实施,解决了8号线与华侨城规划结合的难题,并取得了良好的效果:(1)与建设规划方案相比,缩短了线路长度,节省了工程投资21亿元;(2)通过车站的合理设置,华侨城支线与地铁4号线良好地覆盖了周边区域,有利于区域的快速发展;(3)进行了物业开发,增加了物业面积29 150 m2,加大了地铁的商业价值。

关键词：地铁华侨城引入结合

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Adsorption and retention of fracturing fluid and its impact on gas transport in tight sandstone with different clay minerals

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Petroleum Science 2025年第1期22卷 370-383页

作者： Yi-jun Wang Li-jun You jian Yang Yi-Li Kang Ming-jun Chen jia-jia Bai jian Tian State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation Southwest Petroleum University Engineering Technology Research Institute of Southwest Oil & Gas Field Company PetroChina School of Petroleum Engineering Changzhou University State Key Laboratory of Coal Mine Disaster Dynamics and Control Chongqing University

To elucidate the adsorption characteristics and retention mechanisms of fracturing fluids in diverse clay minerals, we conducted on-line nuclear magnetic resonance(NMR) and atomic force microscopy(AFM)experiments. The depth and extent of solid phase damage are determined by the ratio between the size of fine fractions in fracturing fluid residue and the pore-throat size in experiments. Poor physical properties(K 0.5 m D) combined with a scattered distribution of retained fracturing fluid is associated with high gas phase recovery permeability, whereas a continuous sheet-like distribution results in low recovery permeability. The expansive surface area and presence of filamentous illite minerals facilitate the multiple winding and adsorption of fracturing fluids, demonstrating strong hydrogen-bonding, multi-layering and multiple adsorption properties. The geological characteristics of the main gas formations exhibit significant variation, and the severity of damage caused by fracturing fluids occurs in diverse sequences. To address this issue, a differentiated strategy for optimizing fracturing fluids has been proposed.

关键词： Clay minerals Formation damage Fracturing fluid retention distribution Adsorption morphology

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A sampling method based on URL clustering for fast web accessibility evaluation

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Frontiers of Information Technology & Electronic Engineering 2015年第6期16卷 449-456页

作者： Meng-ni zhang Can WANG jia-jun BU Zhi YU Yu ZHOU Chun CHEN College of Computer Science and Technology Zhejiang University Hangzhou 310027 China

When evaluating the accessibility of a large website, we rely on sampling methods to reduce the cost of evaluation. This may lead to a biased evaluation when the distribution of checkpoint violations in a website is skewed and the selected samples do not provide a good representation of the entire website. To improve sampling quality, stratified sampling methods first cluster web pages in a site and then draw samples from each cluster. In existing stratified sampling methods, however, all the pages in a website need to be analyzed for clustering, causing huge I/O and computation costs. To address this issue, we propose a novel page sampling method based on URL clustering for web accessibility evaluation, namely URLSamp. Using only the URL information for stratified page sampling, URLSamp can efficiently scale to large websites. Meanwhile, by exploiting similarities in URL patterns, URLSamp cluster pages by their generating scripts and can thus effectively detect accessibility problems from web page templates. We use a data set of 45 web sites to validate our method. Experimental results show that our URLSamp method is both effective and efficient for web accessibility evaluation.

关键词： Page sampling URL clustering Web accessibility evaluation

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Glaucomatous retinal ganglion cells:death and protection

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International Journal of Ophthalmology(English edition) 2025年第1期18卷 160-167页

作者： Na Cui jun jia Yuan He Department of Ophthalmology the Second Affiliated Hospital of Xi’an Medical UniversityXi’an 710038Shaanxi ProvinceChina Xi’an Key Laboratory for the Prevention and Treatment of Eye and Brain Neurological Related Diseases Xi’an 710038Shaanxi ProvinceChina

Glaucoma is a group of diseases characterized by progressive optic nerve degeneration,with the characteristic pathological change being death of retinal ganglion cells(RGCs),which ultimately causes visual field loss and irreversible *** intraocular pressure(IOP)remains the most important risk factor for glaucoma,but the exact mechanism responsible for the death of RGCs is currently *** factor deficiency,impaired mitochondrial structure and function,disrupted axonal transport,disturbed Ca2+homeostasis,and activation of apoptotic and autophagic pathways play important roles in RGC death in *** review was conducted using Web of Science,PubMed,Project,and other databases to summarize the relevant mechanisms of death of RGCs in glaucoma,in addition to outlining protective treatments to improve the degradation of RGCs.

关键词： glaucoma retinal ganglion cells neuroprotection progressive death axonal deletion

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Anomalous quality factor evolution of induced transparency in a virtualized coupled-oscillator system

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Science China(Physics,Mechanics & Astronomy) 2025年第1期68卷 144-151页

作者： Yunhan Yang Han jia Tuo Liu Yuzhen Yang jun Yang Key Laboratory of Noise and Vibration Research Institute of AcousticsChinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China State Key Laboratory of Acoustics Institute of AcousticsChinese Academy of SciencesBeijing 100190China

The phenomenon of induced transparency,characterized by a high quality(Q)factor,holds significant importance in the fields of high-precision sensing,energy storage and wave *** transparency systems are often constrained by the limited experimentally accessible parameter space and the lack of independent control over intrinsic parameters,thereby hindering advanced research on high-Q *** we propose a virtualized coupled-oscillator system that enables reconfigurable induced transparency in the reflection *** virtually incorporating a pair of coupled oscillators into an individual acoustic meta-atom,we achieve the manipulation of induced transparency in a decoupled,wide-ranging,and elaborate *** the diverse evolutions across the intrinsic parameter space,we show experimentally a counter-intuitive increase in the Q-factor of the transparency window,which is attributed to the enhanced dissipation of the bright ***,a constant group delay at the center frequency is observed accompanying this *** work demonstrates an intriguing platform as well as a novel strategy to engineer high-Q induced transparency phenomenon,and paves the way towards applications in programmable acoustic sensors,filters and slow-wave devices.

关键词： induced transparency acoustic meta-atom high quality-factor scattering programmable intrinsic parameter

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A Multi-faceted View of the X-Ray Spectral Variability in Seyfert Galaxy Ark 120

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Research in Astronomy and Astrophysics 2025年第1期25卷 228-239页

作者： Lu-Xin Ren jun-Xian Wang jia-Lai Kang CAS Key Laboratory for Research in Galaxies and Cosmology Department of AstronomyUniversity of Science and Technology of China School of Astronomy and Space Science University of Science and Technology of China

Utilizing a range of techniques including multi-band light curves,softness ratio analysis,structure functions,rms spectra,cross-correlation functions,and ratios of spectra from different intervals,we present a comprehensive study of the complex X-ray spectral variability in Seyfert 1 galaxy Ark 120,through re-analyzing its six XMM-Newton observations taken between 2003 and *** find a clear“softer-when-brighter”trend in the 2–10 ke V power-law component over long timescales,with this trend being timescale dependent,as it is much weaker on shorter timescales,similar to that previously detected in NGC ***,a rare“harder-when-brighter”trend is observed during one exposure,indicating dynamic changes in the spectral variability behavior of the power-law *** exceptional exposure,with the spectral variability indeed marked by a power-law pivoting at an unusually low energy of～2 ke V,suggests intricate variations in the thermal Comptonization processes within the ***,when the data below 2 ke V are included,we identify that the soft excess component adds significant complexity to the spectral variability,such as evidenced by a transition from“harder-when-brighter”to“softer-when-brighter”during another single *** extra complexity arises because the variability of the soft excess sometimes follows and sometimes does not follow the changes in the power-law *** findings underscore the necessity of applying multiple analytic techniques to fully capture the multifaceted spectral variability of AGNs.

关键词： galaxies: active galaxies: Seyfert X-rays: galaxies

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Gradient age-precipitation behavior induced by gradient nano-grain in Mg-Gd-Ag-Zr alloy

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Journal of Iron and Steel Research International 2025年第1期32卷 19-24页

作者： Bang-jun Li jia-peng Sun Jing Han Guo-song Wu College of Materials Science and Engineering Hohai UniversityNanjing 210024JiangsuChina School of Mechanical and Electrical Engineering China University of Mining and TechnologyXuzhou 221116JiangsuChina

Gradient nano-grained structure is frequently engineered into metallic materials,including Mg alloys,to achieve superior combination of strength and ***,the influence of this microstructural feature on aging precipitation behavior remains inadequately *** this study,the age-precipitation behavior of a gradient nano-grained Mg-Gd-Ag-Zr alloy prepared via ultrasonic severe surface rolling was *** result indicates that the aging precipitation behavior exhibits a depth-dependent variation within this *** the nano-grained surface layer,hierarchicalβnano-precipitates are predominant,while at greater depths,the precipitates consist ofβnanoparticles located at grain boundaries,along with intragranularβ′andγ″*** formation ofβnano-precipitates deviates from the conventional precipitation behavior observed in Mg-Gd-Ag alloys,and is attributed to the high density of defects induced by the surface nano-grained *** finding advances our understanding of the precipitation behavior in the alloys with heterogeneous microstructure.

关键词： Mg alloy Gradient Precipitation Aging behavior Microstructure

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Partial multi-label learning via label-specific feature corrections

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Science China(Information Sciences) 2025年第03期68卷 95-109页

作者： jun-Yi HANG Min-Ling zhang School of Computer Science and Engineering Southeast University Key Laboratory of Computer Network and Information Integration(Southeast University) Ministry of Education

Partial multi-label learning（PML） allows learning from rich-semantic objects with inaccurate annotations, where a set of candidate labels are assigned to each training example but only some of them are valid. Existing approaches rely on disambiguation to tackle the PML problem, which aims to correct noisy candidate labels by recovering the ground-truth labeling information ahead of prediction model induction. However, this dominant strategy might be suboptimal as it usually needs extra assumptions that cannot be fully satisfied in real-world scenarios. Instead of label correction, we investigate another strategy to tackle the PML problem, where the potential ambiguity in PML data is eliminated by correcting instance features in a label-specific manner. Accordingly, a simple yet effective approach named PASE, i.e., partial multi-label learning via label-specific feature corrections, is proposed. Under a meta-learning framework, PASElearns to exert label-specific feature corrections so that potential ambiguity specific to each class label can be eliminated and the desired prediction model can be induced on these corrected instance features with the provided candidate labels. Comprehensive experiments on a wide range of synthetic and real-world data sets validate the effectiveness of the proposed approach.

关键词： machine learning multi-label learning partial multi-label learning label-specific features feature correction

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Some Eigenvalue Properties of Third-order Boundary Value Problems with Distributional Potentials

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Acta Mathematicae Applicatae Sinica 2025年第1期41卷 179-199页

作者： Hai-yan zhang Ji-jun AO College of Sciences Inner Mongolia University of TechnologyHohhot 010051China

Several eigenvalue properties of the third-order boundary value problems with distributional potentials are ***,we prove that the operators associated with the problems are self-adjoint and the corresponding eigenvalues are ***,the continuity and differential properties of the eigenvalues of the problems are given,especially we find the differential expressions for the boundary conditions,the coefficient functions and the ***,we show a brief application to a kind of transmission boundary value problems of the problems studied here.

关键词： third-order boundary value problems distributional potentials quasi-derivatives eigenvalues

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