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SiCp/Al复合材料在常规与超声振动辅助条件的切削过程和表面形成的有限元分析

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制造技术与机床 2024年第4期 51-56页

作者：马国红张加力闫帆施訸曦刘莉太原科技大学机械工程学院山西太原030024 山西黄河呼延建设工程有限公司山西太原030023

SiCp/Al复合材料是一种典型的难加工的材料,由于其基体中颗粒增强导致常规切削中加工质量差、切削阻力高、加工损伤高,机械加工性差,常规切削已不能满足加工要求。通过切削仿真,对比分析常规与超声振动辅助切削条件下复合材料的切削过程... 详细信息

SiCp/Al复合材料是一种典型的难加工的材料,由于其基体中颗粒增强导致常规切削中加工质量差、切削阻力高、加工损伤高,机械加工性差,常规切削已不能满足加工要求。通过切削仿真,对比分析常规与超声振动辅助切削条件下复合材料的切削过程、SiC颗粒的损伤特性、工件的表面形貌与亚表面损伤。结果表明,相比于常规切削,超声振动辅助切削可以提高复合材料的表面完整性,减少复合材料的亚表面损伤,并且能够提高工件的表面质量。

关键词： SiCp/Al复合材料有限元模拟超声振动辅助切削切削机理表面质量

基于VMD-SSA-LSTM考虑刀具磨损的数控铣床切削功率预测模型研究

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中国机械工程 2024年第6期35卷 1052-1063页

作者：王秋莲欧桂雄徐雪娇刘锦荣马国红邓红标南昌大学经济管理学院南昌330031 南昌大学先进制造学院南昌330031

传统的切削过程功率获取需要基于复杂的切削功率模型且很少考虑刀具磨损的影响,针对此设计了一种基于变分模态分解(VMD)、麻雀搜索算法(SSA)、长短时记忆(LSTM)神经网络的考虑刀具磨损的数控铣床切削功率预测模型,该模型无需解构数控铣... 详细信息

传统的切削过程功率获取需要基于复杂的切削功率模型且很少考虑刀具磨损的影响,针对此设计了一种基于变分模态分解(VMD)、麻雀搜索算法(SSA)、长短时记忆(LSTM)神经网络的考虑刀具磨损的数控铣床切削功率预测模型,该模型无需解构数控铣床运行过程的能耗机理,基于一次性的历史实验数据即可实现数控铣床切削过程功率的高精度预测。首先,采用人工智能机器视觉技术对刀具磨损图片进行分析处理,获取刀具磨损图像的数字化特征,从而得到刀具最大磨损量;然后,建立基于VMD-SSA-LSTM考虑刀具磨损的数控铣床切削功率预测模型,利用VMD对数控铣床运行数据进行分解,采用SSA算法对LSTM神经网络超参数进行寻优,并将分解出的铣床运行数据分量输入到LSTM神经网络中,接着将每个分量的预测值相加,得到切削功率预测值;最后以面铣加工为例,将所提出的预测模型与BP神经网络、LSTM神经网络和传统模型进行对比分析,验证了所提模型的有效性和优越性。

关键词：切削过程功率刀具磨损麻雀搜索算法长短时记忆神经网络变分模态分解计算机视觉技术

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浮游植物与鲢肌肉营养水平关系分析

山东师范大学学报（自然科学版） 2024年第2期39卷 184-192页

作者：徐海强王俊鹏杜兴华马国红山东省淡水渔业研究院济南250013

为了详细了解浮游植物存量和鲢肌肉营养品质之间的关系,对东平湖、微山湖春、夏、秋、冬四季浮游植物及同一时间、同一水域鲢肌肉营养水平进行了调查,探讨分析了两者之间的亲密联系,并与同时期养殖鲢肌肉营养成分进行了比较,结果表明:1... 详细信息

为了详细了解浮游植物存量和鲢肌肉营养品质之间的关系,对东平湖、微山湖春、夏、秋、冬四季浮游植物及同一时间、同一水域鲢肌肉营养水平进行了调查,探讨分析了两者之间的亲密联系,并与同时期养殖鲢肌肉营养成分进行了比较,结果表明:1)鲢肌肉蛋白、氨基酸、脂肪酸组成与含量与浮游植物的种类和生物量关系密切;2)秋末冬初浮游植物种类和生物量更有利于鲢生长,鱼类肌肉营养水平为一年中最高;3)自然水域鲢肌肉营养品质与鲜美度均高于养殖鲢。

关键词：浮游植物鲢粗蛋白氨基酸脂肪酸

Ultrafast photocarrier and coherent phonon dynamics in type-II Dirac semimetal PtTe2 thin films probed by optical spectroscopy

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Photonics Research 2022年第3期10卷 653-661页

作者： Peng Suo Shengnan Yan Ruihua Pu Wenjie Zhang Di Li Jiaming Chen Jibo Fu Xian Lin Feng Miao Shi-Jun Liang Weimin Liu guohong ma Department of Physics Shanghai UniversityShanghai 200444China National Laboratory of Solid State Microstructures School of PhysicsCollaborative Innovation Center of Advanced MicrostructuresNanjing UniversityNanjing 210093China School of Physical Science and Technology ShanghaiTech UniversityShanghai 201210China

We report the ultrafast photocarrier dynamics and coherent phonon excitation in type-II Dirac semimetal platinum ditelluride(PtTe2)thin films via femtosecond(fs)pump-probe spectroscopy at room *** analysis revealed that the incoherent electronic relaxation consists of two components:a subpicosecond fast relaxation process and a slow component with a time constant of hundreds of picoseconds(ps).Furthermore,the launch of a coherent acoustic phonon(CAP)in the 20 nm film but absence in the 6.8 nm film uncovers the dominant role of temperature gradient in producing a strain *** sound velocity and Young’s modulus in the thick PtTe_(2) are determined to be 1.736 km/s and 29.5 GPa,*** addition,the coherent optical phonon(COP)with a frequency of 4.7 THz corresponding to Te atoms out-of-plane A1g vibration has been well resolved in all films,which is ascribed to displacive excitation of coherent phonon(DECP).The observation of a strong probe-wavelength dependent COP amplitude reveals the resonant feature of the optical excitation-induced atomic displacement in *** findings provide deep insight into the excitation and dynamics of CAP and COP as well as the photocarriers’recovery pathway and lifetimes in PtTe_(2).Our study also demonstrates that the COP spectroscopy is a powerful tool to reveal the modulation of frequency-dependent optical constants induced by atomic vibrations,which may find applications in the fields of optoelectronics and ultrafast photonics.

关键词： coherent phonon excitation

Ultra-sensitive Dirac-point-based biosensing on terahertz metasurfaces comprising patterned graphene and perovskites

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Photonics Research 2022年第2期10卷 280-288页

作者： Xin Yan Tengteng Li guohong ma Ju Gao Tongling Wang Haiyun Yao maosheng Yang Lanju Liang Jing Li Jie Li Dequan Wei Meng Wang Yunxia Ye Xiaoxian Song Haiting Zhang Chao ma Yunpeng Ren Xudong Ren Jianquan Yao School of Opto-electronic Engineering Zaozhuang UniversityZaozhuang 277160China College of Precision Instruments and Opto-electronics Engineering Tianjin UniversityTianjin 300072China Department of Physics School of ScienceShanghai UniversityShanghai 200444China School of Telecommunications Qilu University of TechnologyJinan 250306China Institute of Micro-nano Optoelectronics and Terahertz Technology College of Information Science and EngineeringJiangsu UniversityZhenjiang 212013China

Biosensors are a focus of research on terahertz metasurfaces. However, reports of ultra-sensitive biosensors based on Dirac points are rare. Here, a new terahertz metasurface is proposed that consists of patterned graphene and perovskites. This serves as an ultra-sensitive Dirac-point-based biosensor for qualitative detection of ***, sericin may make graphene n-doped and drive the Fermi level to shift from the valence band to the Dirac point, causing a dramatic decrease in conductivity. Correspondingly, the dielectric environment on the metasurface undergoes significant change, which is suited for ultra-sensitive biosensing. In addition, metal halide perovskites, which are up-to-date optoelectronic materials, have a positive effect on the phase during terahertz wave transmission. Thus, this sensor was used to successfully detect sericin with a detection limit of 780 pg/m L, achieved by changing the amplitude and phase. The detection limit of this sensor is as much as one order of magnitude lower than that of sensors in published works. These results show that the Dirac-pointbased biosensor is a promising platform for a wide range of ultra-sensitive and qualitative detection in biosensing and biological sciences.

关键词： qualitative point perovskite

Discerning Weld Seam Pro les from Strong Arc Background for the Robotic Automated Welding Process via Visual Attention Features

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Chinese Journal of Mechanical Engineering 2020年第1期33卷 170-181页

作者： Yinshui He Zhuohua Yu Jian Li Lesheng Yu guohong ma School of Environment and Chemical Engineering Nanchang UniversityNanchang 330031China School of Mechanical Engineering Key Laboratory of Lightweight and High Strength Structural Materials of Jiangxi ProvinceNanchang UniversityNanchang 330031China Institute of Technology.East China Jiao Tong University Nanchang 330100China

In the robotic welding process with thick steel plates,laser vision sensors are widely used to profile the weld seam to implement automatic seam *** weld seam profile extraction(WSPE)result is a crucial step for identifying the feature points of the extracted profile to guide the welding torch in real *** visual information processing system may collapse when interference data points in the image survive during the phase of feature point identification,which results in low tracking accuracy and poor welding *** paper presents a visual attention featurebased method to extract the weld seam profile(WSP)from the strong arc background using clustering ***,a binary image is obtained through the preprocessing ***,all data points with a gray value 255 are clustered with the nearest neighborhood clustering ***,a strategy is developed to discern one cluster belonging to the WSP from the appointed candidate clusters in each loop,and a scheme is proposed to extract the entire WSP using visual *** with the previous methods the proposed method in this paper can extract more useful details of the WSP and has better stability in terms of removing the interference *** WSPE tests with butt joints and T-joints show the anti-interference ability of the proposed method,which contributes to smoothing the welding process and shows its practical value in robotic automated welding with thick steel plates.

关键词： Weld seam profile extraction Visual attention features Clustering Robotic welding

超快太赫兹自旋电子学若干关键科学问题的思考

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自然杂志 2023年第4期45卷 308-316页

作者：马国宏上海大学理学院物理系上海200444

超快太赫兹自旋电子学研究的是太赫兹光子与磁振子的相互作用的科学问题,尤其是太赫兹光子与反铁磁磁振子间的相互作用的科学和技术问题。文章针对该领域的研究现状和面临的挑战,从自旋电子学太赫兹辐射源、太赫兹脉冲对反铁磁磁振子的... 详细信息

超快太赫兹自旋电子学研究的是太赫兹光子与磁振子的相互作用的科学问题,尤其是太赫兹光子与反铁磁磁振子间的相互作用的科学和技术问题。文章针对该领域的研究现状和面临的挑战,从自旋电子学太赫兹辐射源、太赫兹脉冲对反铁磁磁振子的激发及调控,以及太赫兹光子与磁振子的强耦合三个方面进行综述与思考,希望能对超快太赫兹自旋电子学的研究起到抛砖引玉的作用。

关键词：太赫兹波磁振子反铁磁磁振子-极化子

一种融合改进A*算法与改进动态窗口法的AGV路径规划

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传感技术学报 2023年第1期36卷 68-77页

作者：潘富强曾成马国红刘继忠南昌大学先进制造学院江西南昌330031

为满足AGV路径规划中路径的全局最优性和实时避障的需要,提出了一种基于改进A*算法与改进动态窗口法的融合算法。首先,基于传统A*算法,提出了一种基于障碍物类型的关键路径点提取策略,剔除冗余路径点,从而减少路径总转角,缩短全局路径长... 详细信息

为满足AGV路径规划中路径的全局最优性和实时避障的需要,提出了一种基于改进A*算法与改进动态窗口法的融合算法。首先,基于传统A*算法,提出了一种基于障碍物类型的关键路径点提取策略,剔除冗余路径点,从而减少路径总转角,缩短全局路径长度;其次,根据提取的关键点计算贝塞尔曲线,生成一条符合机器人运动学的路径;最后,将改进A*算法与改进动态窗口法进行融合,将提取的关键路径点作为改进动态窗口法的过程目标点,并向动态窗口法的评价函数中加入全局路径代价函数,从而使融合算法同时具备全局路径最优性和动态避障能力。仿真实验结果表明:与传统A*算法相比,改进A*算法减少了52.8%的路径点,减少了5.8%的路径总转角,缩短了4.8%的全局路径总长度,而且基于改进A*算法的融合算法相较于基于传统A*算法的融合算法,效率提高了46.3%,能够很好地满足AGV路径规划的需要。最后完成了实际场景下的运行实验验证。

关键词：自动导引运输车路径规划实时避障 A*算法动态窗口法

Photoinduced large polaron transport and dynamics in organic-inorganic hybrid lead halide perovskite with terahertz probes

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Light(Science & Applications) 2022年第8期11卷 1853-1864页

作者： Zuanming Jin Yan Peng Yuqing Fang Zhijiang Ye Zhiyuan Fan Zhilin Liu Xichang Bao Heng Gao Wei Ren Jing Wu guohong ma Qianli Chen Chao Zhang Alexey VBalakin Alexander PShkurinov Yiming Zhu Songlin Zhuang Terahertz Technology Innovation Research Institute Terahertz Spectrum and Imaging Technology Cooperative Innovation CenterShanghai Key Lab of Modern Optical SystemUniversity of Shanghai for Science and TechnologyShanghai200093China Qingdao Institute of Bioenergy and Bioprocess Technology Chinese Academy of SciencesQingdao266101China Physics Department Materials Genome InstituteState Key Laboratory of Advanced Special SteelShanghai Key Laboratory of High Temperature SuperconductorsInternational Centre of Quantum and Molecular StructuresShanghai UniversityShanghai200444China Shanghai Institute of Technical Physics Chinese Academy of SciencesYutian Road 500ShanghaiChina Department of Physics Shanghai University99 Shangda RoadShanghai200444China University of Michigan-Shanghai Jiao Tong University Joint Institute Shanghai Jiao Tong UniversityShanghaiChina School of Physics University of WollongongWollongongNSW2522Australia Department of Physics and International Laser Center Lomonosov Moscow State UniversityLeninskie Gory 1Moscow19991Russia ILIT RAS-Branch of the FSRC《Crystallography and Photonics》RAS Svyatoozerskaya 1140700ShaturaMoscow RegionRussia

Organic-inorganic hybrid metal halide perovskites(MHPs)have attracted tremendous attention for optoelectronic *** long photocarrier lifetime and moderate carrier mobility have been proposed as results of the large polaron formation in ***,it is challenging to measure the effective mass and carrier scattering parameters of the photogenerated large polarons in the ultrafast carrier recombination ***,we show,in a one-step spectroscopic method,that the optical-pump and terahertz-electromagnetic probe(OPTP)technique allows us to access the nature of interplay of photoexcited unbound charge carriers and optical phonons in polycrystalline CH_(3)NH_(3)PbI_(3)(maPbI_(3))of about 10μm grain ***,we demonstrate a direct spectral evidence of the large polarons in polycrystalline maPbI_(3).Using the Drude-Smith-Lorentz model along with the Frӧhlich-type electron-phonon(e-ph)coupling,we determine the effective mass and scattering parameters of photogenerated polaronic *** discover that the resulting moderate polaronic carrier mobility is mainly influenced by the enhanced carrier scattering,rather than the polaron mass ***,the formation of large polarons in maPbI_(3)polycrystalline grains results in a long charge carrier lifetime at room *** results provide crucial information about the photo-physics of maPbI3 and are indispensable for optoelectronic device development with better performance.

关键词： polaron perovskite inorganic