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3D seismic response of a 2D hill-valley staggered topography modeled by a 2.5D multi-domain IBEM

Earthquake Science 2019年第3期32卷 125-142页

作者： Zhenning Ba qiaozhi sang Jianwen Liang Department of Civil Engineering Tianjin UniversityTianjin 300072China Key Laboratory of Coast Civil Structure Safety(Tianjin University) Ministry of EducationTianjin 300072China

A two and a half dimensional(2.5D)multi-domain indirect boundary element method(IBEM)is developed to study the wave scattering of obliquely incident P-,SV-and SH-waves by a hill-valley staggered topography in a multi-layered *** IBEM algorithm includes using 2.5D full-space and half-space Green’s functions to construct scattered fields in decomposed closed and opened half-space regions,respectively,and using the dynamic stiffness method to solve the free *** regions are finally integrated by introducing the compatibility conditions to obtain the total wave *** proposed 2.5D IBEM has the flexibility in dealing with complex boundaries by directly applying the fictitious loads on the regions’boundaries,with a less storage requirement compared to the full 3D ***,by combining the specific advantages of the two kinds of Green’s functions,the method is well suitable for handling coupled topographies with high *** method is validated by comparison with published results for a single valley as well as a single hill *** effects of height-to-width ratio of hill and layering on dynamic responses are further parametrically investigated by numerical implementations in frequency *** show that the interaction between valley and hills can lead to a more significant amplification within the valley region,and dynamic responses are deeply influenced by the height-to-width of hill,simultaneously depending on incident angle and ***,the site effects become more complex when the stratification feature is taken into account.

关键词： 2.5D multi-domain IBEM Green’s functions for moving load hill-valley staggered topography wave scattering layered half-space

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Application of Series Formula Method in Optimization Arrangement of Webs

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World Journal of Engineering and Technology 2018年第3期6卷 651-660页

作者： qiaozhi sang Siwen Li Shuqi Wang Dianxuan Gong Yisheng College North China University of Science and Technology Tangshan China College of Architectural Engineering North China University of Science and Technology Tangshan China College of Science North China University of Science and Technology Tangshan China

The expressions of the internal forces of the webs under the vertical loads of the simply supported beam type trusses with vertical and horizontal webs and without vertical webs are studied through the mathematical formula method. The variations of internal forces under different angles and spacings of the webs are simulated. The law of the optimal arrangement of the webs of the parallel-string simple-beam truss is obtained: under the condition that the rigidity of the rod is allowed, the form of no vertical web-type truss and reducing the span distance and inclination of the side span are advisable, which can save materials and reduce the weight as well. This method can be applied to the calculation of internal forces for arbitrary loads and truss forms.

关键词： Series Formula Method Beam Truss Optimum Arrangement of Webs

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Exploration of Elements Affecting the Main Properties of Screw Steel

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Open Journal of Applied Sciences 2018年第5期8卷 184-188页

作者： Siwen Li qiaozhi sang Shuqi Wang Dianxuan Gong Yisheng College North China University of Science and Technology Tangshan China College of Architectural Engiring North China University of Science and Technology Tangshan China College of Science North China University of Science and Technology Tangshan China

In order to obtain the main and secondary factors affecting the properties of the screw steel and its correlation, this text constructed a TOPSIS (Technique for order performance by similarity to ideal solution) evaluation system based on entropy weight. First of all, three properties indexes of deformed steel bar are selected: the yield strength, tensile strength and elongation at break after breaking. Secondly, we defined a comprehensive index C which is for measuring the property of thread steel by using TOPSIS method, and then the correlation degree of various chemical elements and comprehensive index C were analyzed. According to the principle that the bigger of coefficient correlation, the greater impact, to draw a conclusion: the main elements that affect the properties of deformed steel bar are C, Ceq, Si and Cr, the secondary factors are Mn, Mo, ALT, Ni, Cu, Cr, S, P and V. Finally, the correlation between various elements was studied by means of correlation analysis, where there was a significant positive correlation between Cu and Cr.

关键词： Screw Steel Properties Grey Prediction Correlation Analysis

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基于Davidenkov本构模型的三维沉积盆地非线性地震动谱元法模拟

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岩土工程学报 2024年第7期46卷 1387-1397页

作者：巴振宁赵靖轩桑巧稚梁建文滨海土木工程结构与安全教育部重点实验室天津300350 天津大学中国地震局地震工程综合模拟与城乡抗震韧性重点实验室天津300350 天津大学土木工程系天津300350 同济大学地下建筑与工程系上海200092

为研究三维沉积盆地内低波速土体非线性反应对近断层地震动的影响,实现基于物理的全过程(震源破裂-地震波传播-复杂场地效应-近地表土体非线性反应)三维复杂场地地震动模拟,在谱元SPECFEM3D程序中进行二次开发,采用目前具有丰富工程应... 详细信息

为研究三维沉积盆地内低波速土体非线性反应对近断层地震动的影响,实现基于物理的全过程(震源破裂-地震波传播-复杂场地效应-近地表土体非线性反应)三维复杂场地地震动模拟,在谱元SPECFEM3D程序中进行二次开发,采用目前具有丰富工程应用且适用于不同土类的三参数Martin-Seed-Davidenkov本构模型,结合已有的不规则加卸载准则,通过在程序中修改每个显式时间步下的应力增量,实现了土体剪切模量的实时更新和加卸载拐点的有效识别,将土体的非线性特性纳入到三维复杂场地地震动模拟中。首先将建立的三维模型通过施加合理边界退化至一维,与一维非线性动力分析软件DEEPSOIL的结果进行了对比,验证了开发的正确性;进而将开发的程序应用于中国滇西南地区施甸盆地的非线性地震动模拟,并与相应的线性结果进行了对比。结果显示,受土体非线性的影响,施甸地区PGA和PGV较线性结果峰值均降低,且非线性土体对PGV的影响更加明显,较线性结果最大降低约30%;沉积非线性使沉积内部观测点的速度及其反应谱幅值降低,且特征频率向长周期方向移动。

关键词：非线性地震反应三维沉积盆地 Davidenkov本构模型谱元法

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数字化转型赋能制造业新质生产力发展——基于资源基础理论与动态能力理论的实证研究

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工业技术经济 2025年第1期44卷 12-24页

作者：赵巧芝郭紫晴华北电力大学经济管理系保定071003

通过数字化转型引领新质生产力的发展,是数字经济赋能制造强国建设的重要课题。本文基于资源基础论与动态能力理论,剖析数字化转型驱动制造企业新质生产力发展的影响机理,为赋能新质生产力提供参考。结果发现:(1)数字化转型对制造企业... 详细信息

通过数字化转型引领新质生产力的发展,是数字经济赋能制造强国建设的重要课题。本文基于资源基础论与动态能力理论,剖析数字化转型驱动制造企业新质生产力发展的影响机理,为赋能新质生产力提供参考。结果发现:(1)数字化转型对制造企业新质生产力的长期与短期影响存在差异,短期表现为提升整合、配置及运用资源能力,长期表现为增强其创新变革的感知、抓取与转化能力;(2)实证结果表明,数字化转型对新质生产力的影响显著为正。其中,短期影响的正向作用显著,长期影响不显著。不仅如此,市场竞争强度的正向调节作用不容忽视;(3)根据异质性效应结果,东部地区影响显著为正,中部与西部地区则较为微弱;国有企业的驱动效应明显高于非国有企业样本。研究结论为提升制造业新质生产力水平提供了新的赋能方向。

关键词：数字化转型制造业新质生产力资源基础论动态能力理论赋能机制市场竞争强度异质性效应

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虚拟数字人对用户在线学习效果的影响研究

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现代情报 2025年第1期45卷 81-96页

作者：赵一鸣郑乔治沈校亮武汉大学信息资源研究中心湖北武汉430072 武汉大学信息管理学院湖北武汉430072 武汉大学大数据研究院湖北武汉430072 武汉大学图书情报国家级实验教学示范中心湖北武汉430072

[目的/意义]在教学环境中使用虚拟数字人进行授课可以促使用户更高效地在线学习。本研究旨在探究在线学习中虚拟数字人特征对用户在线学习效果的影响,为在线教学视频设计和教学策略优化提供参考。[方法/过程]结合准社会互动理论,使用VTu... 详细信息

[目的/意义]在教学环境中使用虚拟数字人进行授课可以促使用户更高效地在线学习。本研究旨在探究在线学习中虚拟数字人特征对用户在线学习效果的影响,为在线教学视频设计和教学策略优化提供参考。[方法/过程]结合准社会互动理论,使用VTube Studio软件设计虚拟数字人教学的视频材料,招募用户观看教学视频并测量用户的主观感受,对在线学习中虚拟教师授课的情境进行探究。[结果/结论]虚拟数字人的吸引力、拟人化特征通过用户对虚拟数字人的态度和学习满意度的链式中介作用积极影响在线学习效果,拟人化到学习效果的中介路径之间存在遮掩效应;准社会互动对学习满意度有积极影响,而对学习效果存在负面作用。

关键词：虚拟数字人虚拟人虚拟教师学习效果准社会互动

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高混凝土面板堆石坝接缝止水试验研究和应用

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岩土工程学报 2025年第1期47卷 30-37页

作者：郦能惠王立安任强张志韬张贤王新奇代巧枝南京水利科学研究院岩土工程研究所江苏南京210024 黄河勘测规划设计研究院有限公司河南郑州450031

混凝土面板堆石坝是当前最有竞争力的坝型,为保障高混凝土面板堆石坝的安全,坝体和面板的应力变形性状以及接缝位移成为研究的重点之一,通过止水材料开发、接缝止水结构设计和止水结构防渗模型试验研究提出了高混凝土面板堆石坝新型止... 详细信息

混凝土面板堆石坝是当前最有竞争力的坝型,为保障高混凝土面板堆石坝的安全,坝体和面板的应力变形性状以及接缝位移成为研究的重点之一,通过止水材料开发、接缝止水结构设计和止水结构防渗模型试验研究提出了高混凝土面板堆石坝新型止水结构,并应用于高混凝土面板堆石坝工程。在此基础上进行了高坝新型接缝止水结构力学特性试验研究,形成了试验方法,建立了高坝新型止水结构的劲度表达式,通过在某高坝工程的应用表明提出的接缝止水应力应变关系全面反映高坝新型止水结构各主要部件对于面板与趾板以及面板之间力的传递的贡献,更好地反映复杂地形地质条件下高坝设计布置的影响,具有一定的工程应用价值。

关键词：混凝土面板堆石坝接缝止水应力变形性状劲度表达式

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Study on modal characteristics and vibration reduction of an aircraft rotor–stator brake-induced squeal system

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Acta Mechanica Sinica 2020年第6期36卷 1350-1359,I0004页

作者： qiaozhi Yin Xiaohui Wei Hong Nie Jian Deng State Key Laboratory of Mechanics and Control of Mechanical Structures Nanjing University of Aeronautics and AstronauticsNanjing210016China Key Laboratory of Fundamental Science for National Defense-Advanced Design Technology of Flight Vehicle Nanjing University of Aeronautics and AstronauticsNanjing210016China Nanjing Center for Multifunctional Lightweight Materials and Structures Nanjing University of Aeronautics and AstronauticsNanjing210016China

Based on the modal coupling theory,the rotor and stator contact stiffness and axial relative velocity are considered to build an electric aircraft brake dynamic system model in this *** the complex modal analysis and transient dynamic analysis methods are used to study the aircraft brake squeal performance and vibratory *** unstable vibration modes indicate that the out-of-plane vibration plays an important role and the feed-in energy is larger than the output energy in the brake rotor–stator module so that brake squeal takes *** the influences of the contact stiffness,friction damping and frictional coefficient on the brake squeal system are carried out,laying the foundation for the three proposed vibration suppression *** show that the coefficient negative-slope condition will intensify the ***,a linear relationship between the squeal factor and the frictional coefficient is obtained to provide a guidance to predict squeal stability under more *** reduction design shows that adding a damping layer to the brake mechanism and chamfering the edge of braking stators both can reduce brake squeal effectively,while slotting braking stators is invalid in aircraft braking system.

关键词： Aircraft rotor-stator bake-induced vibration Brake squeal-Vibration stability Modal coupling Vibration suppression

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Parameter effects on high-speed UAV ground directional stability using bifurcation analysis

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Chinese Journal of Aeronautics 2021年第11期34卷 1-14页

作者： qiaozhi YIN Xiaohui WEI Hong NIE Jian DENG State Key Laboratory of Mechanics and Control of Mechanical Structures Nanjing University of Aeronautics and AstronauticsNanjing 210016China Key Laboratory of Fundamental Science for National Defense-Advanced Design Technology of Flight Vehicle Nanjing University of Aeronautics and AstronauticsNanjing 210016China MIIT Key Laboratory of Multifunctional Lightweight Materials and Structures Nanjing University of Aeronautics and AstronauticsNanjing 210016China

A loss of ground directional stability can trigger a high-speed Unmanned Aerial Vehicle(UAV)to veer off the *** order to investigate the combined effects of the key structural and operational parameters on the UAV ground directional stability from a global perspective,a fully parameterized mathematical high-speed UAV ground nonlinear dynamic model is developed considering several nonlinear *** bifurcation analysis procedure of a UAV ground steering system is introduced,following which the simulation efficiency is greatly improved comparing with the time-domain simulation *** the numerical continuation method is employed to investigate the influence of the nose wheel steering angle and the global stability region is *** bifurcation parameter plane is divided into several parts with different stability properties by the saddle nodes and the Hopf bifurcation *** find that the UAV motion states will never cross the bifurcation curve in the nonlinear ***,the dual-parameter bifurcation analyses are presented to give a complete description of the possible steering *** is also found that BT bifurcation appears when the UAV initial rectilinear velocity and the tire frictional coefficient *** addition,results indicate that the influence of tire frictional coefficient has an opposite trend to the influence of initial rectilinear ***,using bifurcation analysis method to identify the parameter regions of a UAV nonlinear ground dynamic system helps to improve the development efficiency and quality during UAV designing phase.

关键词： Bifurcation analysis Ground directional stability High-speed UAV Nonlinear system Numerical continuation

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Robust control of exciting force for vibration control system with multi-exciters

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Science China(Technological Sciences) 2013年第10期56卷 2516-2524页

作者： SONG qiaozhi YANG ZhiChun WANG Wei Institute of Structural Dynamics and Control School of Aeronautics Northwestern Polytechnical University

Due to the dynamical character of electromagnetic exciter and the coupling between structure and exciter(s),the actual output force acting on the structure is usually not equal to the exact value that is supposed to be,especially when multi-exciters are used as actuators to precisely actuate large flexible *** is necessary to consider these effects to ensure the force generated by each exciter is the same as *** this paper,a robust control method is proposed for the multi-input and multi-output(MIMO)structural vibration control system to trace the target actuating force of each exciter.A special signal is designed and put into the coupled mul-ti-exciter-structure system,and the input and output signals of the system are used to build a dynamic model involving both the dynamical characters of the exciters and the structure using the subspace identification *** the uncertainty factors of the multi-exciter/structure system,an H-infinity robust controller is designed to decouple the coupling between structure and exciters based on the identified system model.A MIMO vibration control system combined with a flexible plate and three electromagnetic exciters is adopted to demonstrate the proposed method,both numerical simulation and model experiments showing that the output force of each exciter can trace its target force accurately within the requested frequency band.

关键词： multi-exciters system exciting force control subspace identification robust control experiment modeling

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