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Modelling of dynamic contact length in rail grinding process
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《机械工程前沿(英文)》 2014年 第9卷 第3期 页码 242-248 doi: 10.1007/s11465-014-0305-y
Rails endure frequent dynamic loads from the passing trains for supporting trains and guiding wheels. The accumulated stress concentrations will cause the plastic deformation of rail towards generating corrugations, contact fatigue cracks and also other defects, resulting in more dangerous status even the derailment risks. So the rail grinding technology has been invented with rotating grinding stones pressed on the rail with defects removal. Such rail grinding works are directed by experiences rather than scientifically guidance, lacking of flexible and scientific operating methods. With grinding control unit holding the grinding stones, the rail grinding process has the characteristics not only the surface grinding but also the running railway vehicles. First of all, it’s important to analyze the contact length between the grinding stone and the rail, because the contact length is a critical parameter to measure the grinding capabilities of stones. Moreover, it’s needed to build up models of railway vehicle unit bonded with the grinding stone to represent the rail grinding car. Therefore the theoretical model for contact length is developed based on the geometrical analysis. And the calculating models are improved considering the grinding car’s dynamic behaviors during the grinding process. Eventually, results are obtained based on the models by taking both the operation parameters and the structure parameters into the calculation, which are suitable for revealing the process of rail grinding by combining the grinding mechanism and the railway vehicle systems.
关键词: rail grinding contact length dynamic model Hamiltonian system grinding stone rail grinding car
Subsurface damage pattern and formation mechanism of monocrystalline -GaO in grinding process
《机械工程前沿(英文)》 2022年 第17卷 第2期 doi: 10.1007/s11465-022-0677-3
关键词: monocrystalline beta-phase gallium oxide grinding process subsurface damage nanocrystals amorphous phase
Simulation and analysis of grinding wheel based on Gaussian mixture model
Yulun CHI, Haolin LI
《机械工程前沿(英文)》 2012年 第7卷 第4期 页码 427-432 doi: 10.1007/s11465-012-0350-3
This article presents an application of numerical simulation technique for the generation and analysis of the grinding wheel surface topographies. The ZETA 20 imaging and metrology microscope is employed to measure the surface topographies. The Gaussian mixture model (GMM) is used to transform the measured non-Gaussian field to Gaussian fields, and the simulated topographies are generated. Some numerical examples are used to illustrate the viability of the method. It shows that the simulated grinding wheel topographies are similar with the measured and can be effective used to study the abrasive grains and grinding mechanism.
关键词: grinding wheel 3D topographies measurement Gaussian mixture model simulation
Investigation on drilling-grinding of CFRP
Yanming QUAN, Wenwang ZHONG
《机械工程前沿(英文)》 2009年 第4卷 第1期 页码 60-63 doi: 10.1007/s11465-009-0008-y
关键词: composites drilling-grinding cemented/plated diamond tool life machined quality
Machinability of ultrasonic vibration-assisted micro-grinding in biological bone using nanolubricant
《机械工程前沿(英文)》 2023年 第18卷 第1期 doi: 10.1007/s11465-022-0717-z
关键词: micro-grinding biological bone ultrasonic vibration (UV) nanoparticle jet mist cooling (NJMC) grinding force grinding temperature
《机械工程前沿(英文)》 2023年 第18卷 第1期 doi: 10.1007/s11465-022-0730-2
关键词: ultrasonic vibration-assisted grinding perforated ultrasonic vibration platform vibration characteristics apparent elasticity method grinding force surface integrity
Fiber-reinforced composites in milling and grinding: machining bottlenecks and advanced strategies
《机械工程前沿(英文)》 2022年 第17卷 第2期 doi: 10.1007/s11465-022-0680-8
关键词: milling grinding fiber-reinforced composites damage formation mechanism delamination material removal mechanism surface integrity minimum quantity lubrication
《机械工程前沿(英文)》 2023年 第18卷 第1期 doi: 10.1007/s11465-022-0733-z
关键词: grinding minimum quantity lubrication carbon group nanofluid tribological mechanism
Effects of taping on grinding quality of silicon wafers in backgrinding
Zhigang DONG, Qian ZHANG, Haijun LIU, Renke KANG, Shang GAO
《机械工程前沿(英文)》 2021年 第16卷 第3期 页码 559-569 doi: 10.1007/s11465-020-0624-0
关键词: taping silicon wafer backgrinding subsurface damage surface roughness
Comparative assessment of force, temperature, and wheel wear in sustainable grinding aerospace alloy
《机械工程前沿(英文)》 2023年 第18卷 第1期 doi: 10.1007/s11465-022-0719-x
关键词: grinding aerospace difficult-to-machine material biolubricant physicochemical property grindability
郭孔辉
《中国工程科学》 2000年 第2卷 第8期 页码 25-30
目前国内对中国应不应该发展私用轿车,中国应着重发展什么样的轿车,中国应不应该发展自己的轿车工业,中国轿车工业的出路在哪里,以及应如何发展中国的轿车工业,……等等,讨论颇多,已经成为社会上普遍关心的问题。文章试图分析目前提出的有代表性的各种观点,并对有关问题提出笔者自己的见解,以供参考。笔者认为解决"汽车灾难"问题的根本出路不在抑制私用轿车的发展,而在于发展汽车高新技术,加强城市规划与交通管理。文章在肯定引进合资对提高我国汽车制造技术和管理水平的重要作用的同时,指出它的负面影响是逐渐丧失产品开发的主动权;提出中国汽车工业的总战略应是:"自强不息加国际合作",其中包括:高新技术战略、自主双赢战略、内联自强战略、自主品牌战略和跨越赶超战略。
Recognition of diamond grains on surface of fine diamond grinding wheel
HUO Fengwei, JIN Zhuji, KANG Renke, GUO Dongming, YANG Chun
《机械工程前沿(英文)》 2008年 第3卷 第3期 页码 325-331 doi: 10.1007/s11465-008-0071-9
关键词: topography frequency disturbance filtering analysis wavelength
Energy-saving operation approaches for urban rail transit systems
Ziyou GAO, Lixing YANG
《工程管理前沿(英文)》 2019年 第6卷 第2期 页码 139-151 doi: 10.1007/s42524-019-0030-7
关键词: urban rail transit energy saving speed profile optimization regenerative energy train timetable
CRISPR-Cas9 mediated LAG-3 disruption in CAR-T cells
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《医学前沿(英文)》 2017年 第11卷 第4期 页码 554-562 doi: 10.1007/s11684-017-0543-6
T cells engineered with chimeric antigen receptor (CAR) have been successfully applied to treat advanced refractory B cell malignancy. However, many challenges remain in extending its application toward the treatment of solid tumors. The immunosuppressive nature of tumor microenvironment is considered one of the key factors limiting CAR-T efficacy. One negative regulator of T cell activity is lymphocyte activation gene-3 (LAG-3). We successfully generated LAG-3 knockout T and CAR-T cells with high efficiency using CRISPR-Cas9 mediated gene editing and found that the viability and immune phenotype were not dramatically changed during in vitro culture. LAG-3 knockout CAR-T cells displayed robust antigen-specific antitumor activity in cell culture and in murine xenograft model, which is comparable to standard CAR-T cells. Our study demonstrates an efficient approach to silence immune checkpoint in CAR-T cells via gene editing.
关键词: CAR-T CRISPR-Cas9 LAG-3
Study of Sustainable Urban Rail Transit Development Model in China
Wen-wu Yang
《工程管理前沿(英文)》 2014年 第1卷 第2期 页码 195-201 doi: 10.15302/J-FEM-2014026
关键词: urban rail transit Railway+ Property(R+P) sustainability transit oriented development private public partnership
标题 作者 时间 类型 操作
Machinability of ultrasonic vibration-assisted micro-grinding in biological bone using nanolubricant
期刊论文
characteristics and machining performance of a novel perforated ultrasonic vibration platform in the grinding
期刊论文
Fiber-reinforced composites in milling and grinding: machining bottlenecks and advanced strategies
期刊论文
Tribological mechanism of carbon group nanofluids on grinding interface under minimum quantity lubrication
期刊论文
Effects of taping on grinding quality of silicon wafers in backgrinding
Zhigang DONG, Qian ZHANG, Haijun LIU, Renke KANG, Shang GAO
期刊论文
Comparative assessment of force, temperature, and wheel wear in sustainable grinding aerospace alloy
期刊论文
Recognition of diamond grains on surface of fine diamond grinding wheel
HUO Fengwei, JIN Zhuji, KANG Renke, GUO Dongming, YANG Chun
期刊论文