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A micro-adjusting attitude mechanism for autonomous drilling robot end-effector

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Science China(Information Sciences) 2014年第12期57卷 29-40页

作者： YUAN PeiJiang WANG Qishen SHI ZhenYun WANG TianMiao WANG ChengKun CHEN DongDong shen liheng Robotics Institute Beihang University Beijing Institute of Aerospace Control Devices Shanghai Aircraft Manufacturing Co. Ltd.

Drilling end-effector is a key unit in autonomous drilling *** perpendicularity of the hole has an important influence on the quality of airplane *** at the robot drilling perpendicularity,a micro-adjusting attitude mechanism and a surface normal measurement algorithm are proposed in this *** the mechanism,two rounded eccentric discs are used and the small one is embedded in the big one,which makes the drill’s point static when adjusting the drill’s ***,removal of drill’s point position after adjusting the drill attitude can be *** the micro-adjusting progress,four non-coplanar points in space are used to determine a unique *** normal at the drilling point is measured by four laser ranging *** adjusting angles at which the motors should be rotated to adjust attitude can be calculated by using the deviation between the normal and the drill ***,the motors will drive the two eccentric discs to achieve micro-adjusting *** on drilling robot system and the results demonstrate that the adjusting mechanism and the algorithm for surface normal measurement are effective with high accuracy and efficiency.

关键词： attitude adjusting mechanism drilling end-effector surface normal measurement robot drilling perpendicularity

Neurological Disorders Caused by Structural Dysfunction of VANGL2

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Neuroscience & Medicine 2024年第2期15卷 106-117页

作者： liheng shen Zixiang Xu Xiaobin Xiong Xin sheng Department of Biochemistry Zunyi Medical University Zunyi China

Background: VANGL2 plays a variety of roles in various cellular processes, including tissue morphogenesis, asymmetric cell division, and nervous system development. There is currently a lack of systematic organization in the development and disease of the nervous system. Purpose: To explore the role of VANGL2 in the development of the nervous system and related diseases. Methods: Literature review and analysis of the role of VANGL2 in the development and disease of the nervous system. Results: VANGL2 defects lead to the development of the nervous system through the misconfiguration of various cells, which affects the development of the cochlea, the conduction of neural signals, and the development of nervous system-related diseases such as Alzheimer’s disease, GBM, Bohling-Opitz syndrome, and hydrocephalus. Conclusions: The VANGL2 gene is essential for nervous system development and its deficiency is linked to severe congenital conditions and various disorders, highlighting the need for more research on treatments for related gene defects.

关键词： VANGL2 Neurological Disorders Planar Cell Polarity (PCP) Pathway Neural Tube Defects

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肾病综合征患者牙龈肥大的非手术治疗1例

中华口腔医学杂志 2022年第12期57卷 1247-1250页

作者：沈立恒裴敏钰王静兰州大学口腔医院牙周科兰州730000

药物性牙龈肥大是指长期服用某些药物而引起牙龈的纤维性增生和体积肥大。本文报道1例28岁女性患者因肾病综合征治疗引起药物性牙龈肥大的非手术治疗的全过程, 随访9个月, 患者牙龈恢复正常, 牙周情况保持稳定。

关键词：牙周情况非手术治疗肾病综合征药物性牙龈肥大牙龈纤维性增生女性患者长期服用

Giant excitonic upconverted emission from two-dimensional semiconductor in doubly resonant plasmonic nanocavity

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Light(Science & Applications) 2022年第7期11卷 1523-1534页

作者： Pengfei Qi Yuchen Dai Yang Luo Guangyi Tao liheng Zheng Donglin Liu Tianhao Zhang Jiadong Zhou Bo shen Feng Lin Zheng Liu Zheyu Fang School of Physics State Key Laboratory for Mesoscopic PhysicsAcademy for Advanced Interdisciplinary StudiesCollaborative Innovation Center of Quantum MatterNano-optoelectronics Frontier Center of Ministry of EducationPeking UniversityBeijing 100871China Institute of Modern Optics Nankai UniversityTianjin Key Laboratory of Micro-scale Optical Information Science and TechnologyTianjin 300350China Photonics Research Center School of PhysicsMOE Key Lab of Weak-Light Nonlinear Photonicsand Tianjin Key Lab of Photonics Materials and Technology for Information ScienceNankai UniversityTianjin 300071China School of Electrical and Electronic Engineering Nanyang Technological UniversitySingapore 639798Singapore

Phonon-assisted upconverted emission is the heart of energy harvesting,bioimaging,optical cryptography,and optical *** has been demonstrated that emerging two-dimensional(2D)semiconductors can provide an excellent platform for efficient phonon-assisted upconversion due to the enhanced optical transition strength and phonon-exciton interaction of 2D ***,there is little research on the further enhancement of excitonic upconverted emission in 2D ***,we report the enhanced multiphoton upconverted emission of 2D excitons in doubly resonant plasmonic *** to the enhanced light collection,enhanced excitation rate,and quantum efficiency enhancement arising from the Purcell effect,an upconverted emission amplification of>1000-fold and a decrease of 2~3 orders of magnitude in the saturated excitation power are *** findings pave the way for the development of excitonic upconversion lasing,nanoscopic thermometry,and sensing,revealing the possibility of optical refrigeration in future 2D electronic or excitonic devices.

关键词： converted resonant doubly

Tailoring Bi_(2)Te_(3) edge with semiconductor and metal properties under electron beam irradiation

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Nano Research 2022年第5期15卷 4710-4716页

作者： Ning Cao Peng Liu Jialiang Pan liheng Liang Kunpeng Cai Qingguo Shao Hongwei Zhu Xiaobei Zang School of Materials Science and Engineering China University of Petroleum(East China)Qingdao 266580China State Key Lab of New Ceramics and Fine Processing School of Materials Science and EngineeringTsinghua UniversityBeijing 100084China

In pursuit of miniaturization in the semiconductor industry,two-dimensional(2D)materials are used to fabricate new electronic *** topological insulator(TI)material bismuth telluride(Bi_(2)Te_(3)),as an emerging 2D material,has potential applications in electronic and spintronic devices due to its unique electrical *** is well known that the surface-to-volume ratio increases as the thickness of the material decreases,resulting in a more prominent edge ***,for a single-layer Bi_(2)Te_(3),the atomic structure of the edge plays a crucial role in its electrical ***,combining first-principles calculations and in situ transmission electron microscopy(TEM)experimental studies,we report that there are two types of edge structures in single-layer Bi2Te3:semiconducting flat edges and metallic zigzag *** dynamic evolution process of the edge structure with atomic resolution shows that the proportions of these two edges change with continuous electron beam *** findings demonstrate the viability to use electron beam as an effective tool to precisely tailor the edge of Bi_(2)Te_(3) with desired properties,which paves the way for implementation of single-layer Bi2Te3 in electronics and spintronics.

关键词： Bi_(2)Te_(3)edge electron beam irradiation in situ transmission electron microscopy(TEM) atomic precision

面向订单的航空制造业多工厂生产与运输综合计划模型

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北京航空航天大学学报 2020年第7期46卷 1422-1436页

作者：沈广亚李立恒张宁北京航空航天大学经济管理学院北京100083

在多个异质性离散型生产工厂的航空零部件集成制造环境下,以最小化生产与运输总成本为目标,研究了订单的分配以及零部件加工和成品装配、产品运输的综合计划制定问题,构建了整数规划模型。所建模型既不需要单独引入订单分配决策变量,也... 详细信息

在多个异质性离散型生产工厂的航空零部件集成制造环境下,以最小化生产与运输总成本为目标,研究了订单的分配以及零部件加工和成品装配、产品运输的综合计划制定问题,构建了整数规划模型。所建模型既不需要单独引入订单分配决策变量,也不需要在生产量和运输量的决策变量中添加订单维度,而是通过成品配送约束解决了订单分配决策问题,大幅度减少了决策变量数量,显著降低了模型的复杂度,提升了模型的实用性。以某航空制造企业为例验证了模型的有效性。

关键词：生产计划运输多工厂订单分配航空制造业

Large Rabi splitting obtained in Ag‐WS2 strong‐coupling heterostructure with optical microcavity at room temperature

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Opto-Electronic Advances 2019年第5期2卷 1-9页

作者： Bowen Li Shuai Zu Zhepeng Zhang liheng Zheng Qiao Jiang Bowen Du Yang Luo Yongji Gong Yanfeng Zhang Feng Lin Bo shen Xing Zhu Pulickel M. Ajayan Zheyu Fang School of Physics State Key Laboratory for Mesoscopic Physics Academy for Advanced Interdisciplinary Studies and Nano-optoelectronics Frontier Center of Ministry of Education Peking University Beijing 100871 China Department of Materials Science and Engineering College of Engineering Peking University Beijing 100871 China Department of Materials Science and NanoEngineering Rice University 6100 Main Street Houston TX 77005 USA Collaborative Innovation Center of Quantum Matter Beijing 100871 China

Manipulation of light-matter interaction is critical in modern physics, especially in the strong coupling regime, where the generated half-light, half-matter bosonic quasiparticles as polaritons are important for fundamental quantum science and applications of optoelectronics and nonlinear optics. Two-dimensional transition metal dichalcogenides (TMDs) are ideal platforms to investigate the strong coupling because of their huge exciton binding energy and large absorption coefficients. Further studies on strong exciton-plasmon coupling by combining TMDs with metallic nanostructures have generated broad interests in recent years. However, because of the huge plasmon radiative damping, the observation of strong coupling is significantly limited at room temperature. Here, we demonstrate that a large Rabi splitting (~300 meV) can be achieved at ambient conditions in the strong coupling regime by embedding Ag-WS2 heterostructure in an optical microcavity. The generated quasiparticle with part-plasmon, part-exciton and part-light is analyzed with Hopfield coefficients that are calculated by using three-coupled oscillator model. The resulted plasmon-exciton polaritonic hybrid states can efficiently enlarge the obtained Rabi splitting, which paves the way for the practical applications of polaritonic devices based on ultrathin materials.

关键词： Rabi splitting strong coupling transition metal dichalcogenides optical microcavity surface plasmons

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县域耕地土壤养分时空变异特征研究

干旱地区农业研究 2023年第3期41卷 238-247页

作者：夏利恒申江龙孙语彤刘京陕西地建土地工程技术研究院有限责任公司陕西西安710075 西北农林科技大学资源环境学院陕西杨凌712100 陕西省土地工程建设集团有限责任公司陕西西安710075

土壤养分空间变异研究是精准农业实施的前提,对提高粮食作物单位面积产量和保护农业生态环境具有重要作用。为掌握陕西渭北旱塬区土壤养分时空变异规律,综合空间自相关和重心模型,分析1980—2007年、2007—2017年白水县耕地土壤有机质(S... 详细信息

土壤养分空间变异研究是精准农业实施的前提,对提高粮食作物单位面积产量和保护农业生态环境具有重要作用。为掌握陕西渭北旱塬区土壤养分时空变异规律,综合空间自相关和重心模型,分析1980—2007年、2007—2017年白水县耕地土壤有机质(SOM)、速效磷(AP)和速效钾(AK)的时空变异特征。结果表明:(1)研究区土壤SOM的平均含量分别增加了1.29、3.22 g·kg^(-1),AP的平均含量分别增加了6.89、24.45 mg·kg^(-1),仅有AK的平均含量呈现出先减少后增加的趋势。(2)三期耕地土壤养分的变异系数范围为30.2%~90.8%,属于中等变异。1980—2017年,耕地土壤SOM、AP和AK的全局Moran’s I指数均降低,空间结构性减弱,随机因素作用增强。(3)土壤SOM、AP和AK含量均有不同程度的增加,土壤SOM含量总体呈北低南高分布,土壤AP、AK含量分布情况较为一致,呈东高西低。(4)土壤SOM含量重心在东南方向发生偏移,AP、AK含量重心在东北方向发生偏移。土壤养分标准差椭圆空间分布格局同研究区分布方向一致,转角呈现“增加-减少”的变化规律,椭圆面积减少,养分空间分布趋于集中。该研究探明了白水县土壤养分的空间分布情况与养分重心迁移方向,为合理规划和利用土地资源与土壤养分管理提供依据。

关键词：耕地土壤养分重心模型时空变异

Complex-domain-enhancing neural network for large-scale coherent imaging

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Advanced Photonics Nexus 2023年第4期2卷 79-87页

作者： Xuyang Chang Rifa Zhao Shaowei Jiang Cheng shen Guoan Zheng Changhuei Yang liheng Bian Beijing Institute of Technology MIIT Key Laboratory of Complex-Field Intelligent SensingBeijingChina Beijing Institute of Technology School of Information and Electronics and Advanced Research Institute of Multidisciplinary SciencesBeijingChina Hangzhou Dianzi University School of Communication EngineeringHangzhouChina California Institute of Technology Department of Electrical EngineeringPasadenaCaliforniaUnited States University of Connecticut Department of Biomedical EngineeringStorrsConnecticutUnited States Yangtze Delta Region Academy of Beijing Institute of Technology(Jiaxing) JiaxingChina

Large-scale computational imaging can provide remarkable space-bandwidth product that is beyond the limit of optical *** coherent imaging(CI),the joint reconstruction of amplitude and phase further expands the information throughput and sheds light on label-free observation of biological samples at micro-or even *** existing large-scale CI techniques usually require scanning/modulation multiple times to guarantee measurement diversity and long exposure time to achieve a high signal-to-noise *** cumbersome procedures restrict clinical applications for rapid and lowphototoxicity cell *** this work,a complex-domain-enhancing neural network for large-scale CI termed CI-CDNet is proposed for various large-scale CI modalities with satisfactory reconstruction quality and ***-CDNet is able to exploit the latent coupling information between amplitude and phase(such as their same features),realizing multidimensional representations of the complex *** cross-field characterization framework empowers strong generalization and robustness for various coherent modalities,allowing high-quality and efficient imaging under extremely low exposure time and few data *** apply CI-CDNet in various large-scale CI modalities including Kramers–Kronigrelations holography,Fourier ptychographic microscopy,and lensless coded ptychography.A series of simulations and experiments validate that CI-CDNet can reduce exposure time and data volume by more than 1 order of *** further demonstrate that the high-quality reconstruction of CI-CDNet benefits the subsequent high-level semantic analysis.

关键词： complex-domain neural network coherent imaging phase retrieval