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嫦娥五号探测器自主着陆视觉避障方法与评价

宇航学报 2021年第8期42卷 975-981页

作者：王立刘洋华宝成李涛朱飞虎北京控制工程研究所北京100190

对嫦娥五号探测器的视觉自主避障系统组成、方案及原理进行介绍。采用光学粗避障加激光精避障的两级接力避障模式,在光学粗避障阶段利用K均值聚类对图像障碍进行分割,对分割结果采用Delaunay三角剖分,并设计安全系数评价方法选择安全落... 详细信息

对嫦娥五号探测器的视觉自主避障系统组成、方案及原理进行介绍。采用光学粗避障加激光精避障的两级接力避障模式,在光学粗避障阶段利用K均值聚类对图像障碍进行分割,对分割结果采用Delaunay三角剖分,并设计安全系数评价方法选择安全落点;在激光精避障阶段提出概率模型评价点云所示区域的着陆安全性。对两级避障的在轨图像利用上述方法进行仿真分析,并对着陆区域的安全性进行评价。结果显示两级避障均合理有效。

关键词：嫦娥五号探测器自主着陆视觉避障系统

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小天体在轨渲染观测技术

光学精密工程 2021年第12期29卷 2745-2753页

作者：刘兴潭张成渝武延鹏华宝成吴奋陟中国空间技术研究院北京控制工程研究所北京100190

提出了一种空间光场中小天体在轨序列图像渲染观测方法,综合小天体的表面反射特性、轨道特性与观测需求,提供目标在观测时刻的位姿序列、光照角度和相机特性等参数,生成符合探测器成像特性的物理渲染图像集。完成了三维基准模型的建立... 详细信息

提出了一种空间光场中小天体在轨序列图像渲染观测方法,综合小天体的表面反射特性、轨道特性与观测需求,提供目标在观测时刻的位姿序列、光照角度和相机特性等参数,生成符合探测器成像特性的物理渲染图像集。完成了三维基准模型的建立、反射特性文件的生成及物理渲染的光线追迹。由渲染图像真实度检验与地形三维建模实验,针对糸川小行星在特定观测时刻与位置的图像进行闭环模拟观测验证。实验结果表明,通过匹配重建模型的二维投影地形图,图像灰度值配准的平均均方根误差为0.1785,对应小天体地表0.0628 m左右的海拔高差。该渲染观测方法能够有效服务于小天体地形模型重建与相对导航闭环分析环境的搭建。此外,为满足在轨快速解算需求,提出了归一化光谱与灰度响应的快速转化方法,在精度不变的情况下,解算时间为3.48 s,由数小时缩短至秒级。

关键词：小天体空间光场物理渲染数字地形模型观测平台

B2-CuZr reinforced amorphous alloy matrix composites:A review

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China Foundry 2025年第1期22卷 1-11页

作者： Wei Guo Run-hua huang Zhen Zhang Mi Zhao Jin-cheng Wang Yan-qiang Qiao Shu-lin Lü Shu-sen Wu State Key Lab of Materials Processing and Die&Mould Technology School of Materials Science and EngineeringHuazhong University of Science and TechnologyWuhan 430074China State Key Laboratory of Solidification Processing Northwestern Polytechnical UniversityXi’an 710072China School of Aerospace Engineering Huazhong University of Science and TechnologyWuhan 430074China Research Institute of huazhong University of Science and Technology in Shenzhen Shenzhen 518057GuangdongChina

B2-CuZr phase reinforced amorphous alloy matrix composites has become one of the research hotspots in the field of materials science due to the“transformation-induced plasticity”phenomenon,which makes the composites show better macroscopic plastic deformability and obvious work-hardening behavior compared to the conventional amorphous alloy matrix composites reinforced with ductile ***,the in-situ metastable B2-CuZr phase tends to undergo eutectoid decomposition during solidification,and the volume fraction,size,and distribution of B2-CuZr phase are difficult to control,which limits the development and application of these *** date,much efforts have been made to solve the above problems through composition optimization,casting parameter tailoring,and post-processing *** this study,a review was given based on relevant studies,focusing on the predictive approach,reinforcing mechanism,and microstructure tailoring methods of B2-CuZr phase reinforced amorphous alloy matrix *** research focus and future prospects were also given for the future development of the present composite system.

关键词： amorphous alloy matrix composite B2-CuZr phase plasticity microstructure tailoring

Enhancing entanglement and steering in a hybrid atom–optomechanical system via Duffing nonlinearity

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Chinese Physics B 2025年第2期34卷 124-131页

作者： Ling-Hui Dong Xiao-Jie Wu cheng-hua Bai Shao-Xiong Wu School of Semiconductor and Physics North University of ChinaTaiyuan 030051China

We introduce a novel scheme for achieving quantum entanglement and Einstein–Podolsky–Rosen(EPR) steering between an atomic ensemble and a mechanical oscillator within a hybrid atom–optomechanical system. The system comprises an optical cavity, a two-level atomic ensemble and a mechanical resonator that possesses Duffing nonlinearity. The interaction between these components is mediated by the cavity mode, which is driven by an external laser. Our findings indicate that optimizing the coupling strengths between photons and phonons, as well as between atoms and the cavity,leads to maximal entanglement and EPR steering. The amplitude of the driving laser plays a pivotal role in enhancing the coupling between photons and phonons, and the system maintains robust entanglement and EPR steering even under high dissipation, thereby mitigating the constraints on initial conditions and parameter precision. Remarkably, the Duffing nonlinearity enhances the system's resistance to thermal noise, ensuring its stability and entanglement protection. Our analysis of EPR steering conditions reveals that the party with lower dissipation exhibits superior stability and a propensity to steer the party with higher dissipation. These discoveries offer novel perspectives for advancing quantum information processing and communication technologies.

关键词： quantum entanglement EPR steering optomechanical system Duffing nonlinearity

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状态激励轻敲模式原子力显微镜的设计与仿真

电子显微学报 2011年第1期30卷 1-6页

作者：华宝成钱建强姚骏恩北京航空航天大学仪器科学与光电工程学院北京100191 北京航空航天大学微纳测控与低维物理教育部重点实验室北京100191 北京航空航天大学物理科学与核能工程学院北京100191

为轻敲模式原子力显微镜设计了一种激励方式,在带有状态反馈的轻敲模式原子力显微镜基础上,除去原有的外加激励信号而引入一个自动增益控制环节,用于维持状态反馈信号的幅度恒定,并将此信号作为悬臂振动的激励信号。该激励方式即为状态... 详细信息

为轻敲模式原子力显微镜设计了一种激励方式,在带有状态反馈的轻敲模式原子力显微镜基础上,除去原有的外加激励信号而引入一个自动增益控制环节,用于维持状态反馈信号的幅度恒定,并将此信号作为悬臂振动的激励信号。该激励方式即为状态激励,用于轻敲模式时可称为状态激励轻敲模式原子力显微镜。采用Matlab/Simulink工具实现了对状态激励轻敲模式原子力显微镜系统的建模和数值仿真,起振曲线证明了状态激励信号能够驱动悬臂振动并调整其工作频率;逼近曲线、线扫描曲线等典型功能仿真实验证明了状态激励方式能够成功地应用于轻敲模式成像。

关键词：原子力显微镜轻敲模式状态激励数值仿真

Visible-light-induced ring-opening cross-coupling of cycloalcohols with vinylazaarenes and enones via β-C-C scission enabled by proton-coupled electron transfer

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Chinese Chemical Letters 2025年第2期36卷 400-405页

作者： Qinghong Zhang Qiao Zhao Xiaodi Wu Li Wang Kairui Shen Yuchen hua cheng Gao Yu Zhang Mei Peng Kai Zhao Institute of Advanced Synthesis School of Chemistry and Molecular EngineeringJiangsu National Synergetic Innovation Center for Advanced MaterialsNanjing Tech University College of Chemical Engineering Nanjing Forestry University College of Pharmacy Hengyang Medical SchoolUniversity of South China School of Chemistry and Chemical Engineering Henan Normal University

Pyridyl-based ketones and 1,6-diketones are both attractive and invaluable scaffolds which play pivotal roles in the construction and structural modification of a plethora of synthetically paramount natural products, pharmaceuticals, organic materials and fine chemicals. In this context, we herein demonstrate an unprecedented, robust and generally applicable synthetically strategy to deliver these two crucial ketone frameworks via visible-light-induced ring-opening coupling reactions of cycloalcohols with vinylazaarenes and enones, respectively. A plausible mechanism involves the selective β-C-C bond cleavage of cycloalcohols enabled by proton-coupled electron transfer and ensuing Giese-type addition followed by single electron reduction and protonation. The synthetic methodology exhibits broad substrate scope,excellent functional group compatibility as well as operational simplicity and environmental friendliness.

关键词： 1,6-Diketone C-C Bond cleavage Proton-coupled electron transfer Pyridyl-based ketone Ring-opening coupling

Penile metastasis from colon cancer with BRAF_(V600E)mutation treated with BRAF/MEK-targeted therapy plus cetuximab:A case report

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World Journal of Gastrointestinal Oncology 2025年第3期17卷 402-409页

作者： Jun-Chen Wu hua-Xi cheng Qiu-Sheng Lan He-Yang Xu Yu-Jie Zeng Wei Lai Zhong-hua Chu Department of Gastrointestinal Surgery Sun Yat-sen Memorial HospitalSun Yat-sen UniversityGuangzhou 510120Guangdong ProvinceChina

BACKGROUND The incidence of colon cancer has been progressively increasing over time,whereas penile metastasis of colon cancer has remained exceedingly *** the prognosis for colon cancer with BRAF_(V600E)mutation is relatively unfavorable,further exploration and investigation are still required to develop treatment strategies for such rare *** SUMMARY About one year after surgery and chemotherapy,a 50-year-old patient with sigmoid colon cancer developed a mass at the base of the patient's penis,accompanied by severe tenderness and pain during *** disease progression,multiple metastatic nodules also emerged in other regions of the penis,including the coronal *** nodules located in the coronal sulcus were excised for histopathological *** histopathological findings revealed that the nodules were metastases originating from the sigmoid colon cancer,with a BRAF V600E mutation *** prompted a modification of the therapy regimen of cetuximab,dabrafenib and trametinib,which effectively held back the progression of penile metastasis in the *** Combining the BRAF/MEK-targeted therapy with cetuximab demonstrates a favorable therapeutic response in BRAF_(V600E)-mutated colon cancer with penile metastasis.

关键词： Colon cancer Penile metastasis BRAF_(V600E)mutation Targeted therapy Case report

A single-pixel elemental imaging method using neutron-induced gamma-ray activation

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Nuclear Science and Techniques 2025年第1期36卷 1-12页

作者： Can cheng Yong-Ji Xie Xun-Rong Xia Jia-Yu Gu Dong Zhao Yi-Ze Chen Ai-Yun Sun Xu-Wen Liang Wen-bao Jia Da-Qian Hei Department of Ionizing Radiation and Medical Engineering Jiangsu Institute of MetrologyNanjing 210023China Institute of Nuclear Analytical Technology Nanjing University of Aeronautics and AstronauticsNanjing 211106China China Nuclear Power Engineering Co. LtdBeijing 100840China School of Nuclear Science and Technology Lanzhou UniversityLanzhou 730000China

Neutron-induced gamma-ray imaging is a spectroscopic technique that uses characteristic gamma rays to infer the elemental distribution of an ***,this technique requires the use of large facilities to supply a high neutron flux and a time-consuming detection procedure involving direct collimating *** this study,a new method based on low neutron flux was proposed.A single-pixel gamma-ray detector combined with random pattern gamma-ray masks was used to measure the characteristic gamma rays emitted from the *** of the elemental distribution in the sample,comprising 30×30 pixels,were reconstructed using the maximum-likelihood expectation-maximization *** results demonstrate that the elemental imaging of the sample can be accurately determined using this *** proposed approach,which eliminates the need for high neutron flux and scanning measurements,can be used for in-field imaging applications.

关键词： Elemental imaging Neutron-induced gamma-ray activation Single-pixel imaging

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某牵引车多体系统动力学建模与仿真

上海交通大学学报 2003年第11期37卷 1767-1771页

作者：包继华孙承顺张建武张鑫上海交通大学机械与动力工程学院上海200030

利用多体理论对某牵引车建立了整车非线性系统动力学模型,模型中将钢板弹簧离散为多个无质量Timoshenko梁连接的柔性体,以模拟钢板弹簧的非线性特性.将整车模型在方向盘正弦输入下进行仿真的结果表明,车辆的操纵性能与方向盘输入有较好... 详细信息

利用多体理论对某牵引车建立了整车非线性系统动力学模型,模型中将钢板弹簧离散为多个无质量Timoshenko梁连接的柔性体,以模拟钢板弹簧的非线性特性.将整车模型在方向盘正弦输入下进行仿真的结果表明,车辆的操纵性能与方向盘输入有较好的跟随性,但由于非线性特性的影响而存在滞后现象,同时载荷转移使得车辆转弯时内侧的侧向力比外侧的侧向力小,且变化相对平缓.该模型较好地反映了车辆实际运行的动力学特性,其建模方法可以应用于其他计及非线性效应车辆的动力学响应的研究。

关键词：多体理论钢板弹簧建模仿真