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Micro thermoplastic forming of a Pd-based metallic glass:theory and applications

Journal of Iron and Steel Research International 2017年第4期24卷 378-384页

作者： Can Yang Le-ming Lu Zhi-wu Zhao Jia-hao Li Feng Gong Jiang Ma Guangdong Provincial Key Laboratory of Micro/Nano Optomechatronics Engineering College of Mechatronics and Control EngineeringShenzhen UniversityShenzhen 518060guangdongChina

Metallic glasses（MGs）are considered as the ideal materials for miniature fabrication because of their excellent micro thermoplastic forming ability in the supercooled liquid *** understanding and controlling of micro filling process are fundamental for miniature fabrication and their applications,yet presently remain unresolved issues.A universal kinetic equation was proposed to describe the filling kinetics of viscous metallic glass supercooled liquid in micro molds with general cross sectional shapes by using a Pdbased MG as the modeling material and a series of potential applications based on the micro thermoplastic forming of the MG were developed.

关键词： Metallic glass Supercooled liquid region Micro thermoplastic forming Miniature fabrication

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Stability and Neimark-Sacker bifurcation analysis of a food-limited population model with a time delay

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Chinese Physics B 2013年第3期22卷 67-71页

作者：姜晓伟关治洪张先鹤张顶学刘峰 Department of Control Science and Engineering Huazhong University of Science and Technology College of Mechatronics and Control Engineering Hubei Normal University Petroleum Engineering College Yangtze University Department of Electronic Information and Mechanics China University of Geosciences

In this paper,a kind of discrete delay food-limited model obtained by the Euler method is investigated,where the discrete delay τ is regarded as a *** analyzing the associated characteristic equation,the linear stability of this model is *** is shown that Neimark-Sacker bifurcation occurs when τ crosses certain critical *** explicit formulae which determine the stability,direction,and other properties of bifurcating periodic solution are derived by means of the theory of center manifold and normal ***,numerical simulations are performed to verify the analytical results.

关键词： food-limited model time delay Neimark-Sacker bifurcation periodic solution

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In-situ TEM studies on stick–slip friction characters of sp^(2) nanocrystallited carbon films

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Friction 2022年第10期10卷 1635-1649页

作者： Xue FAN Zelong HU Wenchao HUANG Institute of Nanosurface Science and Engineering Guangdong Provincial Key Laboratory of Micro/Nano Optomechatronics EngineeringCollege of Mechatronics and Control EngineeringShenzhen UniversityShenzhen 518060China

Carbon films with two different kinds of sp^(2) nanocrystallited structure were investigated to study the stick–slip friction with the in-situ and ex-situ ***-situ transmission electron microscope(TEM)observation and nanofriction tests revealed that the origins of stick and slip varied with shear stress and film *** the stick stage,shear stress gradually increased with the contact strengthened until reached the shear strength to break the interfacial adhesion;at the slip stage,the shear stress decreased and accompanied with film *** the sliding process,adhesive deformation resulted in the large stick–slip step while ploughing deformation led to a smoother ***-situ nanofriction tests on a series of sp^(2) nanocrystallited carbon films with different irradiation energies showed the expected sliding behavior with the in-situ *** study first clarified the mechanism of stick–slip friction with the in-situ TEM observation,which plays the important role for the micro and nano application of sp2 nanocrystallited carbon films.

关键词： carbon films stick-slip contact interface deformation in-situ transmission electron microscope(TEM)

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Multiscale frictional behaviors of sp^(2) nanocrystallited carbon films with different ion irradiation densities

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Friction 2021年第5期9卷 1025-1037页

作者： Zelong HU Xue FAN Cheng CHEN Institute of Nanosurface Science and Engineering Guangdong Provincial Key Laboratory of Micro/Nano Optomechatronics EngineeringCollege of Mechatronics and Control EngineeringShenzhen UniversityShenzhen 518060China

sp^(2) nanocrystallited carbon films with large nanocrystallite sizes,smooth surfaces,and relative high hardness were prepared with different ion irradiation densities regulated with the substrate magnetic coil current in an electron cyclotron resonance plasma sputtering *** multiscale frictional behaviors were investigated with macro pin‐on‐disk tribo‐tests and micro nanoscratch *** results revealed that,at an ion irradiation density of 16 mA/cm^(2),sp^(2) nanocrystallited carbon film exhibits the lowest friction coefficient and good wear resistant properties at both the macroscale and *** film sliding against a Si_(3)N_(4) ball under a contact pressure of 0.57 GPa exhibited a low friction coefficient of 0.09 and a long wear life at the ***,the film sliding against a diamond tip under a contact pressure of 4.9 GPa exhibited a stable low friction coefficient of 0.08 with a shallow scratch depth at the *** is suggested that sp^(2) nanocrystallites affect the frictional behaviors in the cases described *** the macroscale,the contact interface via the small real contact area and the sp^(2) nanocrystallited transfer layer dominated the frictional behavior,while the sp^(2) nanocrystallited structure in the film with low shear strength and high plastic resistivity,as well as the smooth surface morphology,decided the steady low nanoscratch properties at the *** findings expand multiscale tribological applications of sp^(2) nanocrystallited carbon films.

关键词： macro‐tribology micro‐tribology sp^(2)nanocrystallite carbon film ion irradiation density

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HYDRODYNAMIC ANALYSIS AND SIMULATION OF A SWIMMING BIONIC ROBOT TUNA

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Journal of Hydrodynamics 2007年第4期19卷 412-420页

作者： CHEN Hong ZHU Chang-an YIN Xie-zhen XING Xiao-zheng CHENG Gang College of Mechatronics and Control Engineering Shenzhen University Shenzhen 518060 China School of Engineering Science University of Science and Technology of China Hefei 230027 China

A dynamic model for undulatory locomotion was proposed to study the swimming mechanism of a developed bionic robot tuna. On the basis of inviscid hydrodynamics and rigid-body dynamics, the momentum and propulsive force required for propelling the swimming robot tuna＇s flexible body was calculated. By solving the established dynamic equations and efficiency formula, the swimming velocity and propulsive efficiency of the bionic robot tuna were obtained. The relationship between the kinematic parameters of the robot tuna＇s body curve and the hydrodynamic performances was established and discussed after hydrodynamic simulations. The results presented in this article can be used to increase the swimming speed, propulsive thrust, and the efficiency of underwater vehicles effectively.

关键词： undulatory locomotion swimming propulsive force efficiency body curve hydrodynamic simulations

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The roles of microstructural anisotropy in tribo-corrosion performance of one certain laser cladding Fe-based alloy

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Friction 2023年第9期11卷 1673-1689页

作者： Weitao SUN Xuehong HUANG Jian ZHANG Bin WANG Xiaoliang LIU College of Mechatronics Engineering Binzhou UniversityBinzhou 256600China Key Laboratory of Solidification Control and Digital Preparation Technology(Liaoning Province) Dalian University of TechnologyDalian 116085China College of Mechatronics Engineering Binzhou PolytechnicBinzhou 256600China

Because of the microstructural anisotropy for laser cladding materials,the tribo-corrosion performance can vary significantly with different *** this study,one certain Fe-based coating was fabricated by laser *** study the effects of anisotropy,three working surfaces(0°,45°,and 90°to the building direction)were machined from the laser cladding samples;as-cast samples with an approximately homogeneous structure were prepared as *** tribo-corrosion tests were conducted in a 3.5 wt%NaCl solution with varying normal loads(5,10,and 15 N).The results demonstrated that the 45°surface has superior friction stability,corrosion resistance,and wear *** was directly related to the crystal orientation and grain boundary *** addition,a refined microstructure may enhance tribo-corrosion properties by increasing deformation resistance and decreasing surface activity.

关键词： laser cladding anisotropy Fe-based tribo-corrosion performance

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Oversized ore segmentation using SAM-enhanced U-Net with self-supervised pre-training and semi-supervised self-training

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Expert Systems with Applications 2025年 285卷

作者： Wang, Wei Yu, Chong Zhang, Tengyu Chen, Feiyu Liu, Yufan Liu, Yaqi Wu, Zongze Shenzhen518107 China School of Software Engineering Xi'an Jiaotong University Xian710049 China College of Mechatronics and Control Engineering Shenzhen University Shenzhen518060 China

Iron ore is a vital industrial material, and ensuring its safe production remains a major research priority for mining enterprises. A common challenge arises when oversized ores are transported on conveyor belts, where they can lead to blockages that, if not quickly detected and addressed, may escalate into more severe safety incidents. In recent years, machine vision technologies driven by deep learning have been utilized to automatically detect large pieces within ore clusters. Current approaches predominantly depend on supervised learning, which requires extensive manual labels to train neural networks. However, the dense distribution and complex shapes of ores make label generation both time-consuming and challenging. As a result, relying solely on a small amount of manual labels limits the model's accuracy and wastes a significant set of unlabeled images. This gap in utilizing unlabeled data and achieving higher accuracy necessitates an improved solution. To address this issue, we propose a SAM-enhanced U-Net model for oversized ore segmentation combining self-supervised pre-training (SSPT), which trains a model on substantial unlabeled data to learn prior knowledge, and semi-supervised self-training (SSST), which leverages a small set of labeled data along with a large volume of pseudo-labels generated by itself. Specifically, to obtain a more powerful feature extractor, the encoder of U-Net is firstly replaced with Vision Transformer Base (ViT-B) from the Segment Anything Model (SAM) based on transfer learning, constructing the SV-Unet. Secondly, to further enhance the backbone representation capability, SV-Unet undergoes an SSPT procedure using Masked AutoEncoder (MAE) on unlabeled ore images. Finally, SV-Unet is iteratively trained adopting an SSST strategy using artificial labels alongside qualified pseudo-labels. The experimental results show that the proposed method boosts the baseline model's average precision for mask (APM) from 36.04 % to 65.08 %, pri

关键词： Semi-supervised learning

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Reconstruction of highly and extremely aberrated wavefront for ocular Shack-Hartmann sensor using multi-task Attention-UNet

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Experimental Eye Research 2025年 255卷 110394页

作者： Tian, Yibin Luo, Zipei Lu, Dajiang Liu, Cheng Wildsoet, Christine College of Mechatronics and Control Engineering & State Key Laboratory of Radio Frequency Heterogenous Integration Shenzhen University Shenzhen 518060 China Department of Optoelectric Information Science and Technology School of Science Jiangnan University Wuxi 214122 China Wertheim School of Optometry and Vision Science University of California Berkeley 94720 CA United States

In certain ocular conditions, such as in eyes with keratoconus or after corneal laser surgery, Higher Order Aberrations (HOAs) may be dramatically elevated. Accurately recording interpretable wavefronts in such highly aberrated eyes using Shack-Hartmann sensor is a challenging task. While there are studies that have applied deep neural networks to Shack-Hartmann wavefront reconstructions, they have been limited to low resolution and small dynamic range cases. In this study, we introduce a multi-task learning scheme for High-Resolution and High Dynamic Range Shack-Hartmann wavefront reconstruction using a modified attention-UNet (HR-HDR-SHUNet), which outputs a wavefront map along with Zernike coefficients simultaneously. The HR-HDR-SHUNet was evaluated on three large datasets with different levels of HOAs (regularly, highly, and extremely aberrated), with successful reconstruction of all aberrated wavefronts, at the same time achieving significantly higher accuracy than both traditional methods and other deep learning networks;it is also computationally more efficient than the latter. © 2025 Elsevier Ltd

关键词： Deep neural network Eye Higher order aberration Multi-task learning Shack-hartmann sensor Wavefront reconstruction

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Study on the interlayer and interphase multiple coordination deformation mechanism of Fe-20.4Cr-4.7Mn-0.27N duplex stainless steel with gradient heterostructure

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Applied Surface Science 2025年 701卷

作者： Li, Lingxiao Yang, Tingsong Liu, Zhilei Feng, Yanfeng Zhang, Xinjun Jin, Miao Chen, Lei Yang, Kun Hao, Shuo School of Quality and Technical Supervision Hebei University Baoding071002 China School of Mechanical and Power Engineering Zhengzhou University Zhengzhou450001 China School of Mechanical Engineering Yanshan University Qinhuangdao066004 China Hebei Technology Innovation Center for Lightweight of New Energy Vehicle Power System Hebei University Baoding071002 China Industrial Science &Technology Institute for Anti-fatigue Manufacturing Zhengzhou450016 China National Engineering Research Center of Flat Rolling Equipment University of Science and Technology Beijing Beijing100083 China Guangdong Provincial Key Laboratory of Micro/Nano Optomechatronics Engineering College of Mechatronics and Control Engineering Shenzhen University Shenzhen518060 China

In this work, ultrasonic rolling treatment was conducted on the surface (USRT) of the Fe-20.4Cr-4.7Mn-0.27N duplex stainless steel plate for 6 passes, its influences on the tensile deformation and damage behaviors were clarified by means of XRD, EBSD, TEM, SEM, etc. The results show that the USRT introduced gradient heterostructure layers with a total volume ratio of about 27 % in the Fe-20.4Cr-4.7Mn-0.27N steel, the α’bcc-martensite proportion increases from 0 % in the base-material core to 5 % on the USRT surface. This leaded to an improvement in yield strength of 125 MPa, an increase in ultimate tensile strength of 17 MPa and a decrease in total elongation of 20 %. Besides, a further increase in α’bcc-martensite proportion of 35 %–38 % was shown in austenite throughout the USRT specimen after tensile fracture. While in ferrite, the dislocation activity in the USRT layer was obviously weaker than that in the base-material core during tensile deformation. The complex coordination deformation behavior is closely associated with the plasticity partitioning difference between the heterogeneous phases and between the heterogeneous layers. This finally leaded to different damage characteristics on the USRT surface from that in the as-annealed specimen. © 2025 Elsevier B.V.

关键词： Tensile strength

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Probabilistic Teleportation of an Arbitrary Two-Qubit State via Positive Operator-Valued Measurement with Multi Parties

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Communications in Theoretical Physics 2017年第4期67卷 377-382页

作者：石磊魏家华李云霞马丽华薛阳罗均文 Information and Navigation College Air Force Engineering University Department of Automatic Control College of Mechatronics and AutomationNational University of Defense Technology

We propose a novel scheme to probabilistically transmit an arbitrary unknown two-qubit quantum state via Positive Operator-Valued Measurement with the help of two partially entangled states. In this scheme, the teleportation with two senders and two receives can be realized when the information of non-maximally entangled states is only available for the senders. Furthermore, the concrete implementation processes of this proposal are presented, meanwhile the classical communication cost and the successful probability of our scheme are calculated.

关键词： probabilistic teleportation positive operator-valued measurement successful probability classical communication cost

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