Shiyou jixie, 2015 高压气井生产管柱内流体的流动会诱发管柱振动，管柱振动会导致其疲劳、磨损甚至破裂，影响气井正常生产。结合油田现场实际，在考虑管柱重力的情况下，研究了高压气井生产管柱的横向振动特性。运用哈密顿原理，建立了包含生产管柱轴向力、管内流体流速和管内外流体压力等因素的生产管柱横向振动模型。运用伽辽金方法求解模型，计算并讨论了管柱重力、气井产量、井底压力和管柱底端轴向力等参数对油管振动频率及稳定性的影响。研究结果表明，管柱重力是生产管柱振动分析中不可忽略的因素；生产管柱的振动频率随着产量 ...
樊洪海 +6 more
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[Effectiveness analysis of single-incision treatment for adjacent two-segmental lumbar disc herniation using uni-portal non-coaxial spinal endoscopic surgery]. [PDF]
Zhongguo Xiu Fu Chong Jian Wai Ke Za ZhiHe C +6 more
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Jianzhu Gangjiegou Jinzhan现行多数规范的型钢混凝土（steel reinforced concrete，SRC）柱轴心受压承载力计算未考虑型钢与钢筋的约束作用，导致计算结果偏保守。本文基于约束混凝土本构关系建立SRC短柱有限元模型，分析各材料的内力分布规律；结合已有文献试验数据和有限元参数分析结果，建立考虑约束作用的SRC长柱轴心受压承载力计算方法。研究表明：当SRC短柱达到轴压峰值荷载时，在型钢与钢筋约束作用下，混凝土平均应力可达到甚至超过其单轴抗压强度。通过引入约束系数可有效提升SRC短柱轴心受压承载力及稳定系数的计算精度 ...
项洪, 唐浩, 曾志攀, 苏友庆
doaj
[Master manipulator of vascular intervention surgical robot based on haptic feedback]. [PDF]
Sheng Wu Yi Xue Gong Cheng Xue Za ZhiHan G, Sun Z, Tang X.
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[Effects of opening toward symptomatic side versus ossified side on effectiveness of unilateral open-door laminoplasty for cervical ossification of posterior longitudinal ligament with symptom-ossification mismatch]. [PDF]
Zhongguo Xiu Fu Chong Jian Wai Ke Za ZhiZhang X, Zhu W, Pan Q.
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[Three-dimensional finite element analysis of the cantilever fixed bridge restoration for mandibular central incisors supported by narrow-diameter implants]. [PDF]
Hua Xi Kou Qiang Yi Xue Za ZhiZhou X, Gong Y, Peng W, Fu G.
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[Prediction of hemodynamic parameters in pathological arterial vessels based on physics-informed neural networks]. [PDF]
Sheng Wu Yi Xue Gong Cheng Xue Za ZhiJi M +5 more
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[Targeted muscle reinnervation for treatment of painful stump neuroma]. [PDF]
Zhongguo Xiu Fu Chong Jian Wai Ke Za ZhiXiong D +6 more
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[Recent Research Progress and Prospects on Periodontitis Affecting Systemic Comorbidities via the Oral-Gut Axis]. [PDF]
Sichuan Da Xue Xue Bao Yi Xue BanZhang S, Li Y, Yang Z, Huang H, Pan Y.
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[Research progress on three-dimensional finite element analysis for fixed implant restoration of edentulous jaw]. [PDF]
Sheng Wu Yi Xue Gong Cheng Xue Za ZhiLan Y, Su B.
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