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Mohammad Javad REZVANIL, Mohammad Hossein KARGARNOVIN, Davood YOUNESIAN
《机械工程前沿(英文)》 2011年 第6卷 第4期 页码 409-418 doi: 10.1007/s11465-011-0245-8
The response of an infinite Timoshenko beam subjected to a harmonic moving load based on the third-order shear deformation theory (TSDT) is studied. The beam is made of laminated composite, and located on a Pasternak viscoelastic foundation. By using the principle of total minimum potential energy, the governing partial differential equations of motion are obtained. The solution is directed to compute the deflection and bending moment distribution along the length of the beam. Also, the effects of two types of composite materials, stiffness and shear layer viscosity coefficients of foundation, velocity and frequency of the moving load over the beam response are studied. In order to demonstrate the accuracy of the present method, the results TSDT are compared with the previously obtained results based on first-order shear deformation theory, with which good agreements are observed.
关键词: timoshenko composite beam pasternak viscoelastic foundation third-order shear deformation theory (TSDT) harmonic moving load
Multi-harmonic forced vibration and resonance of simple beams to moving vehicles
《结构与土木工程前沿(英文)》 页码 981-993 doi: 10.1007/s11709-023-0979-5
关键词: forced vibration linear Euler beam moving load harmonic structure frequency modulation end restraints
Evaluation of the harmonic scalpel in open surgery for abdominal aortic aneurysm
null
《医学前沿(英文)》 2012年 第6卷 第1期 页码 85-88 doi: 10.1007/s11684-012-0174-x
The harmonic scalpel is a hemostatic device primarily designed for use in laparoscopic surgery. During the last few years, many surgeons have begun to use the harmonic scalpel in open surgery. Several papers have cited the benefits of the device compared with conventional knot-tying techniques; however, no evidence showing the advantages of using the harmonic scalpel in complicated abdominal aortic aneurysm (AAA) surgery has been presented. The aim of the present study is to determine the value of the harmonic scalpel in open operation for AAA. A total of 153 patients who underwent open surgery for AAA at the Department of Vascular Surgery of Guangdong General Hospital, China between January 2001 and December 2010, were retrospectively analyzed. Open surgery performed with the harmonic scalpel on 105 patients was compared with open operation using conventional knot-tying techniques on 48 patients. The operative time, intraoperative blood loss, total postoperative drainage fluid volumes, hospital stay, and postoperative complications between the two groups were compared. The harmonic scalpel group was associated with a shorter operation time (113.2±23.6 min vs. 232.1±39.2 min, P<0.01) and lower intraoperative blood loss (126.1±96.6 ml vs. 592.1±207.2 ml, P<0.01). Postoperative drainage fluid volumes were greater in the conventional surgery group than in the harmonic scalpel group (702.1±192.8 ml vs. 198.5±97.4 ml, P<0.01). The hospital stay was shorter for the harmonic scalpel group than for the conventional surgery group (10.7±3.3 d vs. 16.5±4.7 d, P<0.05). No differences between the postoperative complications or hospital mortality of the two groups were found. The harmonic scalpel is a safe and minimally invasive tool in open surgery for AAA and is associated with shorter operative time, shorter hospital stay, and lower intraoperative blood loss and postoperative drainage fluid volumes compared with conventional knot-tying techniques.
关键词: abdominal aortic aneurysm harmonic scalpel minimally invasive
Yufei YUE, Qianming XU, Peng GUO, An LUO
《能源前沿(英文)》 2019年 第13卷 第1期 页码 16-26 doi: 10.1007/s11708-018-0572-0
关键词: tundish induction heating power supply (TIHPS) constant temperature control input harmonic current blocking load voltage feedforward
Zhuchao YE, Huaihai CHEN,
《机械工程前沿(英文)》 2009年 第4卷 第4期 页码 397-400 doi: 10.1007/s11465-009-0044-7
关键词: simply supported beam moving mass (MM) transverse vibration moving finite element (MFE)
Review of pantograph and catenary interaction
Weihua ZHANG, Dong ZOU, Mengying TAN, Ning ZHOU, Ruiping LI, Guiming MEI
《机械工程前沿(英文)》 2018年 第13卷 第2期 页码 311-322 doi: 10.1007/s11465-018-0494-x
The application of electrified railway directly promotes relevant studies on pantograph-catenary interaction. With the increase of train running speed, the operating conditions for pantograph and catenary have become increasingly complex. This paper reviews the related achievements contributed by groups and institutions around the world. This article specifically focuses on three aspects: The dynamic characteristics of the pantograph and catenary components, the systems’ dynamic properties, and the environmental influences on the pantograph-catenary interaction. In accordance with the existing studies, future research may prioritize the task of identifying the mechanism of contact force variation. This kind of study can be carried out by simplifying the pantograph-catenary interaction into a moving load problem and utilizing the theory of matching mechanical impedance. In addition, developing a computational platform that accommodates environmental interferences and multi-field coupling effects is necessary in order to further explore applications based on fundamental studies.
关键词: electrified railway pantograph and catenary interaction contact force variation moving load problem mechanical impedance multi-field
An investigation into the vibration of harmonic drive systems
M. Masoumi, H. Alimohammadi
《机械工程前沿(英文)》 2013年 第8卷 第4期 页码 409-419 doi: 10.1007/s11465-013-0275-5
Harmonic drive systems are precise and specific transmission gear systems which are beneficial in terms of the high transmission ratio and almost zero backlash. These inherent and spectacular properties result in using this mechanism in robotic and space sciences where the precision and lightwieght play an important role. This paper presents a vibration analysis of harmonic drive systems using the shell theory. Equations of vibration for the flexspline and the circular spline of the system are derived and used to find the natural frequencies for both parts and, moreover, vibration response of the system under the operating condition is calculated. Also, obtained vibration equations are utilized to study the effects of different involved parameters such as the geometry of the flexspline and its gear tooth, eccentricity, and unbalancing on the vibrational behavior of the system.
关键词: harmonic drive system strain wave gearing mechanism vibration analysis natural frequencies
Dynamic prediction of moving trajectory in pipe jacking: GRU-based deep learning framework
《结构与土木工程前沿(英文)》 页码 994-1010 doi: 10.1007/s11709-023-0942-5
关键词: dynamic prediction moving trajectory pipe jacking GRU deep learning
《机械工程前沿(英文)》 2021年 第16卷 第4期 页码 765-781 doi: 10.1007/s11465-021-0655-1
关键词: generalized parallel mechanism configurable moving platform gripper mechanism type synthesis kinematic analysis
《机械工程前沿(英文)》 2022年 第17卷 第2期 doi: 10.1007/s11465-022-0674-6
关键词: harmonic drive meshing flexibility matrix meshing force loading backlash flexspline contact analysis
冯兆祥,陈亮,缪长青
《中国工程科学》 2012年 第14卷 第5期 页码 80-84
针对泰州大桥开展结构动力特性计算,分析了不同移动速度以及不同移动荷载大小对于三塔两跨悬索桥结构动力响应的影响。结果表明,三塔两跨悬索桥的一阶竖弯振动基频约为0.08 Hz,远低于载重汽车的固有频率,不会形成共振条件。简单的移动荷载作用下三塔两跨连续支承悬索桥的内力、位移响应与同等静力荷载作用效果比较接近。移动荷载的质量越大、速度越大,结构的内力、位移响应就越大,并与车重呈近似正比例关系。结构内力、位移的荷载放大系数不随移动荷载质量的大小而改变。
Effects of carrier-attached biofilm on oxygen transfer efficiency in a moving bed biofilm reactor
Yanling WEI,Xunfei YIN,Lu QI,Hongchen WANG,Yiwei GONG,Yaqian LUO
《环境科学与工程前沿(英文)》 2016年 第10卷 第3期 页码 569-577 doi: 10.1007/s11783-015-0822-x
关键词: carrier biofilm oxygen transfer efficiency moving bed biofilm reactor
Pengfei LIU, Dawei WANG, Frédéric OTTO, Markus OESER
《结构与土木工程前沿(英文)》 2018年 第12卷 第2期 页码 215-221 doi: 10.1007/s11709-017-0401-2
关键词: semi-analytical finite element method bearing capacity asphalt pavements moving loads dynamic response
The investigation of pressure drop in moving-beds
CHEN Yunhua, ZHU Xuedong, WU Yongqiang, ZHU Zibin
《化学科学与工程前沿(英文)》 2007年 第1卷 第2期 页码 184-189 doi: 10.1007/s11705-007-0034-4
关键词: development cross-flow velocity superficial qualitative account stabilization
标题 作者 时间 类型 操作
Dynamic analysis of composite beam subjected to harmonic moving load based on the third-order shear deformation
Mohammad Javad REZVANIL, Mohammad Hossein KARGARNOVIN, Davood YOUNESIAN
期刊论文
Constant temperature control of tundish induction heating power supply for metallurgical manufacturing
Yufei YUE, Qianming XU, Peng GUO, An LUO
期刊论文
Vibration analysis of a simply supported beam under moving mass based on moving finite element method
Zhuchao YE, Huaihai CHEN,
期刊论文
Review of pantograph and catenary interaction
Weihua ZHANG, Dong ZOU, Mengying TAN, Ning ZHOU, Ruiping LI, Guiming MEI
期刊论文
Design and analysis of the gripper mechanism based on generalized parallel mechanisms with configurable moving
期刊论文
Meshing stiffness property and meshing status simulation of harmonic drive under transmission loading
期刊论文
Effects of carrier-attached biofilm on oxygen transfer efficiency in a moving bed biofilm reactor
Yanling WEI,Xunfei YIN,Lu QI,Hongchen WANG,Yiwei GONG,Yaqian LUO
期刊论文
of semi-analytical finite element method to analyze the bearing capacity of asphalt pavements under moving
Pengfei LIU, Dawei WANG, Frédéric OTTO, Markus OESER
期刊论文