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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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Bigflow: A General Optimization Layer for Distributed Computing Frameworks

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Journal of Computer Science & Technology 2020年第2期35卷 453-467页

作者： Yun-Cong Zhang Xiao-Yang Wang Cong Wang Yao Xu Jian-Wei Zhang Xiao-Dong Lin Guang-Yu Sun Gong-Lin Zheng Shan-Hui Yin xian-jin ye Li Li Zhan Song Dong-Dong Miao Baidu Inc. Beijing 100193China Center for Energy-Efficient Computing and Applications Peking UniversityBeijing 100871China

As data volumes grow rapidly, distributed computations are widely employed in data-centers to provide cheap and efficient methods to process large-scale parallel datasets. Various computation models have been proposed to improve the abstraction of distributed datasets and hide the details of parallelism. However, most of them follow the single-layer partitioning method, which limits developers to express a multi-level partitioning operation succinctly. To overcome the problem, we present the NDD (Nested Distributed Dataset) data model. It is a more compact and expressive extension of Spark RDD (Resilient Distributed Dataset), in order to remove the burden on developers to manually write the logic for multi-level partitioning cases. Base on the NDD model, we develop an open-source framework called Bigflow, which serves as an optimization layer over computation engines from most widely used processing frameworks. With the help of Bigflow, some advanced optimization techniques, which may only be applied by experienced programmers manually, are enabled automatically in a distributed data processing job. Currently, Bigflow is processing about 3 PB data volumes daily in the data-centers of Baidu. According to customer experience, it can significantly save code length and improve performance over the intuitive programming style.

关键词： distributed computing programming model optimization technique

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Twist monomials of binary delta-matroids

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Acta Mathematica Sinica,English Series 2025年

作者： Qi YAN xian'an jin School of Mathematics and Statistics Lanzhou University School of Mathematical Sciences Xiamen University

Recently, we introduced the twist polynomials of delta-matroids and gave a characterization of even normal binary delta-matroids whose twist polynomials have only one term and posed a problem:what would happen for odd binary delta-matroids? In this paper, we show that a normal binary deltamatroid whose twist polynomials have only one term if and only if each connected component of the intersection graph of the delta-matroid is either a complete graph of odd order or a single vertex with a loop.

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Retrospective review of 190 patients treated for parotid tumors： a single institute experience

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Chinese Medical Journal 2013年第5期126卷 988-990页

作者： LI jing-jia ZHANG Ge-hua LIU xian ye jin YANG Qin-tai HUANG Jian-cong WU Si YIN Gen-di Department of Otolaryngology-Head and Neck Surgery ThirdAffiliated Hospital of Sun Yat-sen University GuangzhouGuangdong 510630 China

Salivary gland neoplasms account for 3%-6% of all head and neck neoplasms, and the incidence was estimated to range from 0.4 to 13.5 cases per 100 000 inhabitants annually. Histologically, salivary gland tumors are a diverse group of neoplasms, making it difficult to establish a common standard for diagnosis and treatment. Most of the current studies concerning salivary gland tumors investigated the histological features and clinical manifestations including both major and minor salivary gland tumors, making it difficult to evaluate their real frequency and site distribution. Parotid tumor is the most frequently occurring salivary neoplasms, comprising 60%-80% of all salivary gland tumors. Clinical experience led us to suspect that our epidemiology of parotid tumors in south China may be different from that of other areas in the world. Here, we retrospectively reviewed parotid tumor cases and aimed to summarize the clinical presentation, histological feature, and surgical complications of parotid tumors.

关键词： parotid gland neoplasm surgery complications

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不同控制水平哮喘患者血清中IL-18及IL-33水平的变化及意义

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中国临床医学 2016年第6期23卷 790-793页

作者：解现金叶伶山东省交通医院呼吸内科济南250031 复旦大学附属中山医院呼吸内科上海200032

目的:探讨血清中白细胞介素-18(IL-18)、白细胞介素-33(IL-33)水平在支气管哮喘不同控制水平患者中的变化及其临床意义。方法:选择2014年1月—2015年12月于山东省交通医院呼吸内科诊治的90例哮喘患者(哮喘组)进行研究。根据哮喘控制水... 详细信息

目的:探讨血清中白细胞介素-18(IL-18)、白细胞介素-33(IL-33)水平在支气管哮喘不同控制水平患者中的变化及其临床意义。方法:选择2014年1月—2015年12月于山东省交通医院呼吸内科诊治的90例哮喘患者(哮喘组)进行研究。根据哮喘控制水平分级,将哮喘组患者分为未控制组、部分控制组及控制组3个亚组,每组各30例。另选30例健康对象作为健康组。采用酶联免疫吸附试验(ELISA)检测各组受试者血清中IL-18、IL-33水平,并测定哮喘患者肺通气功能。结果:哮喘组患者血清中IL-18、IL-33水平高于健康组(P0.05)。哮喘组患者第1秒用力呼气容积占预计值百分比(FEV_1%pred)与血清中IL-18水平呈负相关(P<0.05),但与IL-33无显著相关性。在3个哮喘亚组中,患者血清中IL-18和IL-33的表达水平均与FEV_1%pred无显著相关性。结论:哮喘患者血清中IL-18与IL-33水平与其哮喘控制水平相关。

关键词：哮喘白细胞介素-18 白细胞介素-33 哮喘控制肺功能

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Insights into spinal muscular atrophy from molecular biomarkers

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Neural Regeneration Research 2025年第7期20卷 1849-1863页

作者： Xiaodong Xing Xinzhu Liu xiandeng Li Mi Li xian Wu Xiaohui Huang Ajing Xu Yan Liu Jian Zhang Department of Clinical Pharmacy Xinhua HospitalShanghai Jiao Tong University School of MedicineShanghaiChina College of Pharmacy Chongqing Medical UniversityChongqingChina

Spinal muscular atrophy is a devastating motor neuron disease characterized by severe cases of fatal muscle *** is one of the most common genetic causes of mortality among infants aged less than 2 *** research is currently receiving more attention,and new candidate biomarkers are constantly being *** review initially discusses the evaluation methods commonly used in clinical practice while briefly outlining their respective pros and *** also describe recent advancements in research and the clinical significance of molecular biomarkers for spinal muscular atrophy,which are classified as either specific or non-specific *** review provides new insights into the pathogenesis of spinal muscular atrophy,the mechanism of biomarkers in response to drug-modified therapies,the selection of biomarker candidates,and would promote the development of future ***,the successful utilization of biomarkers may facilitate the implementation of gene-targeting treatments for patients with spinal muscular atrophy.

关键词： biomarkers disease progression gene-targeting therapy neurofilaments Nusinersen spinal muscular atrophy(SMA) survival motor neuron therapeutic evaluation treatment outcomes

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略论唐代宰相制度

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史学集刊 2025年第1期 88-97页

作者：孟宪实中国人民大学历史学院北京100872

在中国古代政治制度史中,宰相制度无疑是一个重要课题。众所周知,在讨论中国的皇帝制度时,有一个重要的观点是讨论“君权”与“相权”的斗争,而君权的不断增长、相权的不断被削弱,正是君主专制持续发展的重要途径。事实上,各个时期的宰... 详细信息

在中国古代政治制度史中,宰相制度无疑是一个重要课题。众所周知,在讨论中国的皇帝制度时,有一个重要的观点是讨论“君权”与“相权”的斗争,而君权的不断增长、相权的不断被削弱,正是君主专制持续发展的重要途径。事实上,各个时期的宰相制度既有变迁,又各具特色,从每个朝代的宰相制度是否能够得出君主专制获得发展的结论,显然是需要具体论证的。唐代宰相制度的研究,通常是在三省制的背景下展开的,而唐代的宰相制度也有自己的发展变化。唐代宰相制度经过三个历史时期,政事堂时期是兼职宰相时期,中书门下时期是专职宰相时期。自唐后期至北宋,是首相制时期。唐代宰相制度的变化,是不是君相斗争的结果?而从兼职宰相到专职宰相再到首相制,宰相的职权明显是处在加强的进程中,按照君相斗争的习惯思路,难道是君主在君相斗争中败下阵来?恐怕不能得出这样的结论。此外,唐宋历史的关系,向来有“唐宋变革论”,强调唐宋之别,但从宰相制度来看,唐宋历史的联系性似乎更突出。

关键词：唐代政事堂中书门下首相制

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有机金属卤化物钙钛矿CH_(3)NH_(3)PbBr_(3)的各向异性Rashba效应

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原子与分子物理学报 2025年第6期42卷 153-158页

作者：蔡锦鸿余达明周贤中广东工业大学集成电路学院广州510006

本研究通过密度泛函理论结合全相对论赝势对钙钛矿CH_(3)NH_(3)PbBr_(3)中的各向异性Rashba效应进行了深入研究.发现,Pb-Br八面体的畸变引起了导带最小间隙的三重态在自旋轨道耦合(SOC)效应和晶格形变下的分裂,导致在不同方向上呈现出... 详细信息

本研究通过密度泛函理论结合全相对论赝势对钙钛矿CH_(3)NH_(3)PbBr_(3)中的各向异性Rashba效应进行了深入研究.发现,Pb-Br八面体的畸变引起了导带最小间隙的三重态在自旋轨道耦合(SOC)效应和晶格形变下的分裂,导致在不同方向上呈现出强烈的各向异性.Rashba带分裂的最大系数可达2.0 eV?,并通过分析能级和电荷密度分布解释了Rashba效应的形成机制.这些研究结果有助于深化对CH_(3)NH_(3)PbBr_(3)性质的理解,同时为其在自旋电子学领域的潜在应用提供了理论基础.

关键词：钙钛矿 CH_3NH_3PbBr_3 密度泛函理论自旋轨道耦合

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Large Non-resonant Nonlinear Optical Susceptibility of Cu_(2)O Microcrystallites

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Chinese Physics Letters 1996年第3期13卷 182-184页

作者： WANG You-gui SI jin-hai ZHAO Jiang ZOU Bing-suo ye Pei-xian Institute of Physics Chinese Academy of SciencesBeijing 100080

We report the measured results of non-resonant nonlinearity by degenerate four-wave mixing for Cu2O nanopartides having central diameter of 9 *** value of x^(3) obtained in a 10ns pulse experiment is 8.48×1O^(-10) es... 详细信息

关键词： resonant nonlinearity Nonlinear

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On spectral theory of the Riemann zeta function

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Science China Mathematics 2019年第11期62卷 2317-2330页

作者： xian-jin Li Department of Mathematics Brigham Young University

Every nontrivial zero of the Riemann zeta function is associated as eigenvalue with an eigenfunction of the fundamental differential operator on a Hilbert-P′olya space. It has geometric multiplicity one. A relation between nontrivial zeros of the zeta function and eigenvalues of the convolution operator is given. It is an analogue of the Selberg transform in Selberg’s trace formula. Elements of the Hilbert-P′olya space are characterized by the Poisson summation formula.

关键词： Hilbert-Pólya space spectrum of operators zeros of zeta function

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