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Numerical study of the semi-circular bend dynamic fracture toughness test using discrete element models

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Science China(Technological Sciences) 2015年第9期58卷 1587-1595页

作者： zhao GaoFeng KAZERANI Tohid MAN Ke GAO Mz zhao Jian State Key Laboratory of Hydraulic Engineering Simulation and Safety School of Civil Engineering Tianjin University Centre for Infrastructure Engineering and Safety School of Civil and Environmental Engineering University of New South Wales State Key Lab of Hydraulics and Mountain River Engineering Sichuan University Civil Engineering School Faculty of Engineering University of Nottingham University Park Beijing Research Institute of Uranium Geology Department of Civil Engineering Monash University

The semi-circular bend(SCB) dynamic fracture toughness test is simulated using discrete element models. The influence of the frictional boundary condition, constitutive law and specimen thickness on the test measurements is investigated. It is found that friction between loading plates and the rock specimen affects the test results. Therefore, friction must be carefully considered to obtain accurate measurements. The simulation results also show that in contrast to the 2D model in which a rate-dependent cohesive law must be introduced, 3D models with a rate-independent law can produce good results. Furthermore, the study suggests that test measurements are seriously affected by specimen thickness; thus, full 3D modeling is required for simulation of the SCB test.

关键词： dynamic fracture toughness rock discrete element model friction

精准管理，助推教师培训取得实效——贯彻二十大精神，培养高素质教师队伍

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黑龙江教师发展学院学报 2025年第03期44卷 19-22页

作者：赵岩松黑龙江教师发展学院

党的二十大报告指出，要培养高素质教师队伍。为此，我国各级教育行政部门积极开展了“国培、省培、市培、县培、校培”五级教师培训。要想使“五级”教师培训取得实效，必须精准管理，要想精准管理必须明确培训管理内涵、明确培训管理... 详细信息

党的二十大报告指出，要培养高素质教师队伍。为此，我国各级教育行政部门积极开展了“国培、省培、市培、县培、校培”五级教师培训。要想使“五级”教师培训取得实效，必须精准管理，要想精准管理必须明确培训管理内涵、明确培训管理方法、明确培训管理目的和作用、明确培训管理程序。只有这样才能提升教师教育教学能力和素养，进一步培养高素质教师队伍。

关键词：高素质教师队伍教师培训精准管理实效

A microvascular image analysis method for optical-resolution photoacoustic microscopy

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Journal of Innovative Optical Health Sciences 2020年第4期3卷 69-79页

作者： Jingxiu zhao Qian zhao Riqiang Lin Jing Meng School of Information Science and Engineering Qufu Normal University 80 Yantai Road North Rizhao 276826P.R.China Shenzhen Institutes of Advanced Technology Chinese Academy of Sciences Institute of Biomedical and Health Engineering 1068 Xueyuan Avenue Shenzhen 518055 P.R.China

Optical-resolution photoacoustic microscopy(OR-PAM)has been shown to be an excellent tool for high-resolution imaging of microvasculature,and quantitative analysis of the microvascula-ture can provide valuable information for the early diagnosis and treatment of various vascular-related *** order to address the characteristics of weak signals,discontinuity and small diameters in photoacoustic microvascular images,we propose a method adaptive to the micro-vascular segmentation in photoacoustic images,including Hessian matrix enhancement and the morphological connection *** accuracy of our vascular segmentation method is quantitatively evaluated by the multiple *** obtain more precise and continuous mi-crovascular skeletons,an improved skeleton extraction framework based on the multistencil fast marching(MSFM)method is *** carried out in vivo OR-PAM microvascular imaging in mouse ears and subcutaneous hepatoma tumor model to verify the correctness and superiority of our proposed *** with the previous methods,our proposed method can extract the microvascular network more completely,continuously and accurately,and provide an ef-fective solution for the quantitative analysis of photoacoustic microvascular images with many small branches.

关键词： Biomedical photonics photoacoustic imaging optical microscopy microvascularnetwork

职业院校服务陕西数字乡村高质量发展的路径研究

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安徽农业科学 2025年第4期53卷 274-278页

作者：赵国锋西安航空职业技术学院马克思主义学院陕西西安710089

数字乡村是伴随网络化、信息化和智能化在乡村经济社会发展中的应用以及农民现代信息技能的提高而内生的乡村现代化发展和转型进程。职业院校在数字乡村发展中以培养数字新农人、提供数字新农技、提升乡村治理水平等为现代乡村发展赋能... 详细信息

数字乡村是伴随网络化、信息化和智能化在乡村经济社会发展中的应用以及农民现代信息技能的提高而内生的乡村现代化发展和转型进程。职业院校在数字乡村发展中以培养数字新农人、提供数字新农技、提升乡村治理水平等为现代乡村发展赋能增效,成为数字乡村发展的内驱力和主要着力点。通过梳理职业院校服务陕西数字乡村发展的应然价值、发展现状及存在问题,提出以下路径和建议:以市场引导激活职业院校服务热情,提升数字乡村发展内驱力;以专业设置提升职业院校服务针对性,带动产教融合精准匹配;以设施支撑保障职业院校服务可靠性,加速数字乡村提质升级;以政策制度完善职业院校服务规范性,强化数字乡村转型力度等。

关键词：职业教育数字乡村高质量发展陕西路径

高频重复经颅磁刺激联合多巴丝肼治疗帕金森病合并焦虑抑郁患者的疗效观察

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中国实用神经疾病杂志 2025年第2期28卷 177-180页

作者：赵启媛丛光燕吕鸿燕张勇李苇胡盼盼汪凯安徽医科大学附属六安医院安徽六安237000 安徽医科大学第一附属医院安徽合肥230032

目的探讨高频重复经颅磁刺激(rTMS)与多巴丝肼联用在帕金森病(PD)伴焦虑和抑郁症状患者中的应用价值。方法选取2021-01—2022-12于安徽医科大学附属六安医院接受治疗的76例PD合并焦虑抑郁症患者为研究对象,分为单药物治疗组及高频rTMS... 详细信息

目的探讨高频重复经颅磁刺激(rTMS)与多巴丝肼联用在帕金森病(PD)伴焦虑和抑郁症状患者中的应用价值。方法选取2021-01—2022-12于安徽医科大学附属六安医院接受治疗的76例PD合并焦虑抑郁症患者为研究对象,分为单药物治疗组及高频rTMS联用药物治疗组,对比分析2组患者治疗前和治疗4周后日常生活能力量表(ADL)、汉密尔顿焦虑测评量表(HAMA)及汉密尔顿抑郁测评量表(HAMD)评分。结果单药物治疗组患者与高频rTMS联用药物治疗组患者治疗前的ADL、HAMA、HAMD评分比较均无统计学差异(P>0.05),治疗后的ADL评分[(62.37±10.57)分比(75.16±9.90)分]、HAMA评分[(17.76±3.67)分比(11.87±2.71)分]、HAMD评分[(20.16±2.52)分比(14.82±2.58)分]比较有统计学差异(P0.05),高频rTMS联合药物组患者ADL评分、HAMA评分和HAMD评分均较治疗前显著改善,差异有统计学意义(P<0.01)。结论PD合并焦虑抑郁患者应用高频rTMS联合药物治疗,能显著改善其日常生活能力及焦虑抑郁情绪,为临床治疗PD合并焦虑抑郁患者提供了新的治疗思路。

关键词：帕金森病焦虑抑郁重复经颅磁刺激多巴丝肼日常生活能力

A design of novel photonic crystal fiber with low and flattened dispersion for supporting 84 orbital angular momentum modes

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Communications in Theoretical Physics 2021年第8期73卷 124-138页

作者： Lijuan zhao Haiying zhao Zhiniu Xu Ruoyu liang School of Electrical and Electronic Engineering North China Electric Power UniversityBaoding071003China Hebei Key Laboratory of Power Internet of Things Technology North China Electric Power UniversityBaoding 071003China Baoding Key Laboratory of Optical Fiber Sensing and Optical Communication Technology North China Electric Power UniversityBaoding 071003China

A dual-guided photonic crystal fiber(PCF) with low and flattened dispersion is designed, which can support a large number of orbital angular momentum(OAM) modes. The properties of the proposed PCF are systematically analyzed through the finite element method. The results show that the proposed PCF can support up to 84 OAM modes with 600 nm bandwidth ranging from 1000 to1600 nm. All values of mode purity are above 91.7%, the isolation parameters are larger than 67 dB and the maximum value up to 145 dB, the lowest confinement loss is only 5×10^(-13) dB·m^(-1).More importantly, the values of dispersion for all modes are less than 40 ps·km-1·nm-1, and the lowest dispersion variation is only 0.7 ps·km^(-1)·nm^(-1). These superior optical properties make the proposed PCF have great advantage in stable transmissions of data and long-distance optical fiber communication system with large capacity.

关键词： photonic crystal fiber orbital angular momentum optical communication finite element method flattened dispersion

Combined effects of axial load and temperature on finite deformation of incompressible thermo-hyperelastic cylinder

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Applied Mathematics and Mechanics(English Edition) 2019年第4期40卷 499-514页

作者： Jie XU Xuegang YUAN Hongwu ZHANG Zhentao zhao Wei zhao State Key Laboratory of Structural Analysis for Industrial Equipment Department of Engineering Mechanics Dalian University of Technology School of Science Dalian Minzu University

A finite deformation problem is examined for a cylinder composed of a class of incompressible thermo-hyperelastic Mooney-Rivlin materials under an equal axial load at its two fixed ends and a temperature field at its lateral boundary. Firstly, a thermomechanical coupling term is taken into account in the strain energy density function, and a governing equation of the problem is obtained. Secondly, an implicit analytical solution is derived by using the incompressibility and the boundary conditions. Significantly, numerical examples show that the middle portion of the cylinder undergoes almost a uniform radial deformation. However, the deformation near the two ends varies remarkably along the axial direction for relatively large axial loads. In addition, the rising temperature can increase the deformation of structures, and its influence is linear approximately. Specially,in the case of tensile load, the jump increase of the axial deformation may occur.

关键词： incompressible thermo-hyperelastic cylinder fixed end axial load implicit analytical solution tensile instability

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茨维塔耶娃与花楸树

哈尔滨学院学报 2025年第1期046卷 79-82页

作者：郭照君天津师范大学文学院

茨维塔耶娃是俄罗斯文学中最有特色的抒情诗人之一，被布罗茨基称为“二十世纪的第一诗人”。她热爱大自然，崇尚自由，常以自然意象入诗。花楸树在俄罗斯有着独特的文化内涵，是俄罗斯诗人常用的诗歌意象。文章从茨维塔耶娃诗歌中的花... 详细信息

茨维塔耶娃是俄罗斯文学中最有特色的抒情诗人之一，被布罗茨基称为“二十世纪的第一诗人”。她热爱大自然，崇尚自由，常以自然意象入诗。花楸树在俄罗斯有着独特的文化内涵，是俄罗斯诗人常用的诗歌意象。文章从茨维塔耶娃诗歌中的花楸树入手，分析茨维塔耶娃对花楸树意象的传承与突破，从而进一步探析茨维塔耶娃诗歌中花楸树的独特性。

关键词：俄罗斯文化茨维塔耶娃花楸树

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复杂地质下超长隧道多种初期支护施工技术

工程建设与设计 2025年第2期 110-112页

作者：赵国伟中铁十九局集团有限公司北京100000

为探究复杂地质条件下超长隧道多种初期支护施工技术,以昆明(福德立交)至宜良高速公路阳宗隧道为工程背景,首先,对该隧道的结构特点以及地质水文情况进行了梳理,其次,基于该隧道各种复杂地质情况,对该隧道超前支护和初期支护关键施工内... 详细信息

为探究复杂地质条件下超长隧道多种初期支护施工技术,以昆明(福德立交)至宜良高速公路阳宗隧道为工程背景,首先,对该隧道的结构特点以及地质水文情况进行了梳理,其次,基于该隧道各种复杂地质情况,对该隧道超前支护和初期支护关键施工内容进行了详细研究,并对基岩裂隙孔隙富水区、断层破碎带和高地应力等不良地质施工提出了应对控制措施,减少了此类不良地质施工过程中的安全风险。

关键词：复杂地质超长隧道多种初期支护不良地质施工