Results 31 to 40 of about 16,478 (205)
Jianzhu Gangjiegou Jinzhan, 2018 选取几何法及撑杆控制面积法确定环索预应力比,选取支座径向位移相等准则及网壳顶点竖向位移相等准则确定环索预应力幅值,将它们进行交叉组合构成4个环索预应力设计方案。另外还选取刚性索法及改进刚性索法作为环索预应力设计方案。以2008年北京奥运会羽毛球馆屋盖弦支穹顶结构为背景建立了算例结构模型。以结构重量为目标函数,考虑构件的长细比约束、强度应力约束、稳定应力约束和结构位移约束,考虑12个设计荷载工况。基于上述6个环索预应力设计方案,采用ANSYS编程语言分别编制结构优化设计程序,以确定最优的环索预应力设计方案。
刘树堂, 黄卫林
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Review of Policy Research, EarlyView.Abstract Populist radical right parties are on the rise all over Europe. Recent literature investigates their effects on environmental policy, however, often applying an overly broad perspective on the policy area and neglecting causal mechanisms. This article addresses both gaps in an in‐depth case study of partisan effects on Swedish environmental ...
Lars E. Berker
wiley +1 more source
Jianzhu Gangjiegou Jinzhan相较于分块预制桥面板，横向全宽预应力预制桥面板的整体性更好，施工更快捷，因此在装配式组合梁桥中具有较好的应用前景。负弯矩作用下预制桥面板的湿接缝连接是受力的关键部位，因此对负弯矩作用下全宽预应力预制桥面板组合梁的力学性能进行研究，考察了横向预应力筋数量、预应力筋布置方式、剪力连接程度、接缝处材料对结构破坏模式、开裂荷载、抗弯承载力、荷载-位移曲线等力学特性的影响，揭示了预制板接缝处的应力分布规律；针对完全剪力连接的预制桥面板组合梁，提出了负弯矩作用下挠度计算的改进有效惯性矩叠加法 ...
陈娟 +4 more
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Jianzhu Gangjiegou Jinzhan, 2016 针对预应力钢柱基底含摩擦型消能装置的耐震性能进行研究,探讨初始钢绞线预应力与消能装置的影响。通过钢绞线施拉预应力接合钢柱与基础,用来提供钢柱自复位能力;消能装置采用摩擦型消能,提供柱构件与基础接合的滞回消能能力,因此柱构件在受震后拥有自复位与无残余变形特性。研究参数包含初始预应力大小、摩擦消能面积与摩擦型消能装置的位置。通过理论推导建立预应力与消能装置在钢柱与基础接合的性能模式,进而设计试件进行试验来验证其性能。试验结果表明,柱与基础接合面有开启与闭合的现象;提高摩擦型消能装置螺栓的预应力量 ...
陈诚直 +3 more
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Jianzhu Gangjiegou Jinzhan, 2023 为研究残余应力对钢梁内嵌式的预应力简支组合梁在火灾效应下的受力性能的影响，通过ABAQUS软件建立钢梁内嵌式的预应力简支钢-混组合梁几何非线性和材料非线性的有限元模型，利用热力-耦合法计算组合梁在高温下的结构响应行为。通过对梁的截面温度、整体挠度和跨中挠度、跨中截面应力分布、拉索应力和塑性变形、梁的整体曲率和跨中曲率等特性在高温下的结构响应进行考察，探究工程应用中常见初始残余应力对组合梁的影响机理。结果表明：残余应力主要是通过影响钢梁的截面模量，进而对钢梁的截面抗弯刚度产生影响 ...
刘雨晨, 郑志远
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Public perception of Ghana's Free Senior High School policy: A north–south comparative analysis
Review of Policy Research, EarlyView.Abstract Ghana's Free Senior High School (SHS) policy, implemented in 2017, aims to increase access to secondary education, promote equity, enhance educational outcomes, and foster human capital development. This study examines public perception of the Free SHS policy, focusing on the variations between the northern and southern regions of Ghana and ...
Michael K. Dzordzormenyoh +3 more
wiley +1 more source
Jianzhu Gangjiegou Jinzhan, 2021 采用有限元软件ABAQUS建立了用于模拟预应力组合梁在火灾下全过程受力行为的模型,研究拉索防火涂层对预应力连续组合梁抗火性能的影响。考察组合梁跨中挠度、拉索应力及塑性应变随温度的变化,分析了预应力组合梁在高温下的温度变化和破坏模式。结果表明:钢梁下翼缘与腹板升温较快,二者温差很小,而腹板与上翼缘的温差较大;混凝土截面各测点处升温速率由下至上依次降低,上表面与下表面的最高温度差可达约700℃;当拉索有5 mm厚防火涂层时,在升温前期其温度随时间延长而上升的幅度比无防火层时温度上升的幅度要小,同一升温时间下,
周焕廷 +5 more
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Detection of canine external ear canal lesions using artificial intelligence
Veterinary Dermatology, EarlyView.Background – Early and accurate diagnosis of otitis externa is crucial for correct management yet often can be challenging. Artificial intelligence (AI) is a valuable diagnostic tool in human medicine. Currently, no such tool is available in veterinary dermatology/otology.
Neoklis Apostolopoulos +3 more
wiley +1 more source
Validating the parental reflective functioning questionnaire ‐ infant version using a rasch model
Infant Mental Health Journal: Infancy and Early Childhood, Volume 46, Issue 4, Page 445-458, July 2025.Abstract Parental reflective functioning is the parent's ability to reflect on the psychological processes in their child and in themselves as a parent. Recently, an infant version of the Parental Reflective Functioning Questionnaire, PRFQ‐I, has been developed and validated using confirmatory factor analyses.
Anne Christine Stuart +4 more
wiley +1 more source
Jianzhu Gangjiegou Jinzhan, 2022 为研究腹板开孔对端部约束预应力波纹钢-混凝土组合梁抗火性能的影响，采用有限元软件ABAQUS对该类组合梁在高温作用下的力学性能进行了非线性有限元分析，研究了具有端部约束预应力波纹腹板开孔组合梁的内力、跨中挠度演化过程以及破坏模式，并对其耐火性能进行了参数分析。结果表明：受约束预应力波纹腹板开孔组合梁在高温作用下的破坏模式为开孔截面腹板与端部截面波纹腹板及钢梁下翼缘发生局部屈曲；随着温度的升高，组合梁由压弯发展至拉弯的悬链线阶段；在荷载比相同、孔洞均位于剪弯区的条件下，开孔尺寸越大 ...
周焕廷 +3 more
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