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This paper is focused on the structural behavior of the single shear bolted connections with thin-walled ferritic stainless steel.The purpose of this study is to investigate the ultimate behaviors,such as ultimate strength and fracture mode of the single shear bolted connections of thin-walled ferritic stainless steel(low cost steel) rather than austenitic stainless steel(high cost steel).Bolt arrangement and end distance parallel to the direction of applied load are considered as main variables of the test specimens for bolted connections.Specimens have a constant dimension of edge distance perpendicular to the loading direction,bolt diameter,pitch,and gauge.A monotonic tensile test for specimens has been carried out and some bolted connections with long end distance showed curling(out of plane deformation) occurrence which led to strength reduction.The ultimate behaviors such as fracture mode,ultimate strength are compared with those predicted by current design codes.Further,conditions of curling occurrence and the strength reduction due to curling are investigated and modified strength equations are suggested considering the curling effect. 相似文献
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柴明良 汪炳良 KIM Jae-yeoul LEE Jong-min KIM Doo-hwan 《Journal of Zhejiang University. Science. B》2003,(3)
INTRODUCTIONCreepingbentgrass (AgrostispalustrisHuds.)isanoutstandingcool seasonspeciesavailableforuseongolfcourseputtinggreens,tees,andcloselymowedfairways.Althoughco lonialbentgrass (AgrostistenuisSibth .Fl.Ox en .)isnotwelladaptedtotheverylowmowingheig… 相似文献
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The concept of the green building as sustainable construction has continuously been studied,developed and distributed.Technologies to realize the green building to use less energy,while protecting the ... 相似文献
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为深入理解 N d0 .52 Sr0 .48Mn O3薄膜中的庞磁电阻效应 ,运用数学解析以及物理概念分析的方法 ,对 Wagner等人提出的在 Nd0 .52 Sr0 .48Mn O3薄膜中庞磁电阻随磁场变化规律的模型进行了分析 ,并对该模型的自洽性进行了讨论 .结果发现只有通过某些必要的修正 ,Wagner模型方可自洽 .还研究了 Nd0 .52 Sr0 .48Mn O3薄膜中大自旋极化子 (large spin po-larons)在居里温度附近的行为特征 ,发现在居里温度附近磁性团簇的尺寸变化较为异常 ,对此现象的物理机制进行了初步探讨 相似文献
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张家口学院成为2018年北京冬奥组委授牌的首批11家北京2022年冬奥会和冬残奥会培训基地之一后,学院开设了冰雪运动课程,培养与冰雪运动相关的志愿性人才和工作者,为满足地域发展需求不断努力。在发展过程中,学校教学质量的高低和教学方法手段的应用及教学效果的有效评价有着紧密的关联,将PDCA循环法引入张家口学院冰雪运动课程教学质量管理中,通过多次的循环发展来发现教学过程中存在的问题并提出解决办法,使冰雪运动课程的教学质量不断改进和提升。 相似文献
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CODY S. DING KIM SONG LLOYD I RICHARDSON 《Educational Studies A Journal of the American Educational Studies Association》2013,49(3):279-295
A persistent belief in American culture is that males both outperform and have a higher inherent aptitude for mathematics than females. Using data from two school districts in two different states in the United States, this study used longitudinal multilevel modeling to examine whether overall performance on standardized as well as classroom tests reveals a gender difference in mathematics performance. The results suggest that both male and female students demonstrated the same growth trend in mathematics performance (as measured by standardized test scores) over time, but females' mathematics grade-point average is significantly higher than males. These results are discussed in the context of present day standardized assessment in the United States that may motivate teachers to focus on higher expectations for mathematics performance regardless of gender, thus challenging cultural beliefs that stigmatize mathematics as masculine in the United States. 相似文献
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