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基于一致性理论的无人机编队控制与集结方法

北京航空航天大学学报 2024年第5期50卷 1646-1654页

作者：苟进展梁天骄陶呈纲马波王海峰吴宇重庆大学航空航天学院重庆400044 歼击机综合仿真航空科技重点实验室成都610091

针对无人机运动学模型特点和远距离成形问题,提出一种基于改进一致性算法的无人机集结-成形策略。建立能直观描述编队队形的坐标系,根据纵向和横航向解耦的带自动驾驶仪的无人机三自由度运动学模型的特点,考虑无人机机动性能约束,对一... 详细信息

针对无人机运动学模型特点和远距离成形问题,提出一种基于改进一致性算法的无人机集结-成形策略。建立能直观描述编队队形的坐标系,根据纵向和横航向解耦的带自动驾驶仪的无人机三自由度运动学模型的特点,考虑无人机机动性能约束,对一致性算法进行改进,实现对无人机速度、航向和飞行高度的控制,提出编队队形控制算法。针对无人机初始间距大带来的调参问题,增加集结过程,并利用粒子群算法优化集结速度,避免航迹冲突,集结结束后再采用所提算法生成无人机航迹,提升算法的适应性。仿真结果表明:所提算法能使无人机在满足机动性约束的情况下,形成稳定队形;相比于直接成形法,所提策略提高改进一致性算法的适应性和安全性。

关键词：无人机编队飞行集结一致性理论粒子群优化

Physical design of target station and neutron instruments for China Spallation Neutron Source

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Science China(Physics,Mechanics & Astronomy) 2013年第12期56卷 2410-2424页

作者： WANG FangWei liang tianjiao YIN Wen YU QuanZhi HE LunHua TAO JuZhou ZHU Tao JIA XueJun ZHANG ShaoYing Beijing National Laboratory for Condensed Matter Physics Institute of PhysicsChinese Academy of Sciences Dongguan Branch Institute of High Energy PhysicsChinese Academy of Sciences

The China Spallation Neutron Source(CSNS)is the first accelerator-based multidiscipline user facility to produce pulsed neutrons by tungsten target under collision of a pulsed proton beam with a beam power of 100 kW at a repetition rate of 25 *** this paper,we focus on the physical design of CSNS target station and neutron *** optimized design,the flat tungsten target and the compact target-moderator-reflector coupling enhance effective cold and thermal neutron output from *** wing-type moderators supply four different characteristics of neutrons to 19 beamlines primarily for neutron scattering *** of neutron instruments are conceptually planned for total 20 beamlines,the configuration and specification have been determined for three day-one neutron *** designs are optimized for the Phase I of 100 kW with a upgradable capacity to 500 kW.

关键词： neutron scattering spallation neutron source neutron diffraction neutron shielding

Measurements and characteristics of Al_(2)O_(3):Cr^(3+) coating for the proton beam imaging system

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Radiation Detection Technology and Methods 2017年第1期1卷 54-60页

作者： Zhirong Zeng Quanzhi Yu Shaohong Wei Bin Zhou Quan Ji tianjiao liang Yuanbo Chen Institute of High Energy Physics Chinese Academy of Sciences(CAS)Beijing 100049China Dongguan Neutron Science Center Dongguan 523803China Beijing National Laboratory for Condensed Matter Physics Institute of PhysicsChinese Academy of ScienceBeijing 100190China

Introduction To set up an online proton beam diagnostic system near the neutron production target of China Spallation Neutron Source(CSNS),a luminescence coating sprayed on the target windowand a corresponding optic system were *** the work,the fabrication of Al_(2)O_(3):Cr^(3+) coating was *** on the sprayed samples were performed to analyze the characteristics of the Al_(2)O_(3):Cr^(3+) *** and tests of coating samples Three kinds of powders with different Cr concentrations were used to fabricate the luminescence coating *** flame spraying,plasma spraying and D-gun spraying processes were ***(PL),X-ray diffraction(XRD),scanned electron mirror(SEM)and radioluminescence experiment by 300 MeV deuterium beam were carried out to analyze and characterize the *** The emission spectrum excited by 532-nm laser has two obvious peaks at 692.9 nm and 694.3 *** samples by flame spraying process with the powders obtained from melting method show higher luminescence intensity than the samples by plasma spraying *** is observed that the luminescence intensity has some relationships with the alpha phase in the samples,which is deduced from the XRD and photoluminescence tests results.A lower temperature during the flame spraying process will help to keep more alpha phase in the *** selected four samples show successful fluoresced results in the radioluminescence *** The luminescence intensity of the coating is improved greatly by the studies on the fabrication process and the characteristics of the *** luminescence coating used in beam diagnostics will be fabricated by the confirmed technical *** works will be continued to improve the characteristics of the luminescence light by controlling Cr concentration and annealing in 1200∼2000℃ environment in the future.

关键词： Al_(2)O_(3):Cr^(3+)luminescence coating Beam diagnostics Spallation target

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基于改进一致性算法的无人机编队控制

航空学报 2020年第9期41卷 167-185页

作者：吴宇梁天骄重庆大学航空航天学院重庆400044 歼击机综合仿真航空科技重点实验室成都610091

编队飞行是指多架无人机保持以一定队形进行飞行的状态,相比于单架飞机执行任务,无人机编队能够增加搜索面积,提高飞机飞行性能,增大完成任务成功率。编队控制是实现编队安全高效完成指定任务的前提。本文以一致性理论为基础,针对无人... 详细信息

编队飞行是指多架无人机保持以一定队形进行飞行的状态,相比于单架飞机执行任务,无人机编队能够增加搜索面积,提高飞机飞行性能,增大完成任务成功率。编队控制是实现编队安全高效完成指定任务的前提。本文以一致性理论为基础,针对无人机运动模型的特点与实际飞行要求,对基本的一致性算法进行改进,提出了改进一致性无人机编队控制算法。首先利用纵向和横侧向解耦的自动驾驶仪模型给出了无人机的三自由度运动方程,根据机动性与飞行性能要求定义了各方向上的加速度、速度与角速度约束。基于一致性理论,将编队控制分为平面与纵向2个方向进行,在状态控制的基础上,利用各状态变量间的几何关系对无人机运动自由度进行转换,加入编队队形信息,设计了编队控制算法。为了使算法生成的指令信号满足约束条件,提出了"最小调整"约束条件处理策略。依据粒子群算法对各无人机的爬升加速度进行优化,以避免机间碰撞。仿真结果表明:提出的编队控制算法具备编队成形与变换功能,能够使无人机编队状态快速收敛到指定值,且保持指定队形,无人机飞行状态满足所有约束条件。

关键词：无人机编队编队控制一致性理论约束条件处理粒子群算法

Investigation of Export Aquaculture in Zhanjiang City and Development Suggestions

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Animal Husbandry and Feed Science 2014年第6期6卷 308-311页

作者： liang tianjiao Ye Shengquan Lao Tongfen Wang Yu Guangdong Provincial Key Laboratory of Aquatic Product Processing and Safety Key Laboratory of Advanced Processing of Aquatic Products of Guangdong Higher Education InstitutionCollege of Food Science and TechnologyGuangdong Ocean University Zhanjiang Entry-Exit Inspection and Quarantine Bureau

History of aquaculture in Zhanjiang City was reviewed by reviewing literatures, human resources, cultured species and culture modes, and distribution of aquaculture system were investigated and summarized. Output and export of processed aquatic products of Zhanjiang in the past years were analyzed, and the role of export aquaculture in economic development and social construction of Zhanjiang City was explored, and suggestions were given for enhancing the development of local export aquaculture.

关键词： Zhanjiang Export Aquaculture Investigation Suggestion

Design of imaging system for CSNS near-target beam diagnostics

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Radiation Detection Technology and Methods 2018年第2期2卷 38-46页

作者： Zhirong Zeng Shanhua Zhang Weilin Cheng Quanzhi Yu Shaohong Wei Bin Zhou Donghui Zhu Quan Ji Aijun Zeng tianjiao liang Yuanbo Chen Institute of High Energy Physics Chinese Academy of Sciences(CAS)Beijing 100049China Dongguan Neutron Science Center Dongguan 523803China Shanghai Institute of Optics and Fine Mechanics Chinese Academy of ScienceShanghai 201800China Beijing National Laboratory for Condensed Matter Physics Institute of PhysicsChinese Academy of ScienceBeijing 100190China

Introduction China Spallation Neutron Source(CSNS)is an accelerator-based pulsed neutron source which produces neutron with spallation reaction induced by proton bombarding tungsten *** increasing beam powers and influences on target,near-target monitoring becomes extreme *** this situation,an optical imaging system for proton beam diagnostics and monitoring near the target is being developed at CSNS,which can provide real-time images of the beam on target and beam distribution *** imaging system design and development In the design of CSNS target imaging system,coating of Cr^(3+):Al_(2)O_(3) is used to convert particle radiation into emission *** to the geometry limits of CSNS target station,a special optical system was designed and fabricated to collect the emission *** the proton beams strike on the target,the coating on the target will be excited,emitting luminescence at the same *** mirrors and lenses of the optical system image the distribution of emission light into a radiation-hard imaging fiber,which transmits the images to the GigE camera located at low-dose area outside of the target *** was written on the LabView platform to control the camera and analyze the images on ***-up of the imaging system was manufactured to test and evaluate the performances of the *** important characteristics of the system were obtained and *** Tests on the mock-up of the system present reliably expectation for beam *** imaging system has been installed at CSNS *** work will be continued to improve the properties of the system.

关键词： Beam diagnostics Beam profile Imaging system Luminescent coating

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BNCT中子源的研发现况与展望

科学通报 2022年第14期67卷 1471-1478页

作者：傅世年梁天骄陈和生中国科学院高能物理研究所北京100049 散裂中子源科学中心东莞523803 中国科学院大学核科学与技术学院北京100049

硼中子俘获疗法(boron neutron capture therapy,BNCT)治疗癌症是一种典型的二元疗法,它既需要高品质的中子束,又需要高靶向性的含硼药物,两者缺一不可、密切配合,方可对肿瘤实现细胞级精准的靶向杀伤.BNCT治疗方法显著的优越性的背后,... 详细信息

硼中子俘获疗法(boron neutron capture therapy,BNCT)治疗癌症是一种典型的二元疗法,它既需要高品质的中子束,又需要高靶向性的含硼药物,两者缺一不可、密切配合,方可对肿瘤实现细胞级精准的靶向杀伤.BNCT治疗方法显著的优越性的背后,是对中子源和载硼药物特性的很高要求.含硼药物研究涉及多学科,包括放射学、化学、医学、药学、生物学和物理学等.本文主要讨论BNCT中子源的问题.首先,介绍BNCT对中子束特性要求的国际标准,回顾几十年来BNCT中子源发展的困难所在;然后,展现近年来加速器中子源异军突起、开创BNCT新未来的前景,明确研发中的核心技术;最后,报告我国在此领域前沿研究的最新成果及其发展展望.

关键词：硼中子俘获疗法(BNCT) 强流质子加速器中子源载硼靶向药物

First neutron Bragg-edge imaging experimental results at CSNS

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Chinese Physics B 2021年第9期30卷 45-48页

作者： Jie Chen Zhijian Tan Weiqiang Liu Sihao Deng Shengxiang Wang Liyi Wang Haibiao Zheng Huaile Lu Feiran Shen Jiazheng Hao Xiaojuan Zhou Jianrong Zhou Zhijia Sun Lunhua He tianjiao liang Institute of High Energy Physics Chinese Academy of Sciences(CAS)Beijing 100049China Spallation Neutron Source Science Center(SNSSC) Dongguan 523803China Beijing National Laboratory for Condensed Matter Physics Institute of PhysicsChinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China

The neutron Bragg-edge imaging is expected to be a new non-destructive energy-resolved neutron imaging technique for quantitatively two-dimensional or three-dimensional visualizing crystallographic information in a bulk material,which could be benefited from pulsed neutron *** we build a Bragg-edge imaging system on the General Purpose Powder Diffractometer at the China Spallation Neutron *** residual strain mapping of a bent Q235 ferrite steel sample has been achieved with a spectral resolution of 0.15%by the time-of-flight neutron Bragg-edge imaging on this *** results show its great potential applications in materials science and engineering.

关键词： neutron Bragg-edge imaging China Spallation Neutron Source

Id2 epigenetically controls CD8^(+)T-cell exhaustion by disrupting the assembly of the Tcf3-LSD1 complex

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Cellular & Molecular Immunology 2024年第3期21卷 292-308页

作者： Yiming Li Mingwei Han Haolin Wei Wan Huang Zhinan Chen tianjiao Zhang Meirui Qian Lin Jing Gang Nan Xiuxuan Sun Shuhui Dai Kun Wang Jianli Jiang Ping Zhu liang Chen Department of Cell Biology of National Translational Science Center for Molecular Medicine and Department of Clinical Immunology of Xijing Hospital Fourth Military Medical UniversityXi’anShaanxi 710032China State Key Laboratory of New Targets Discovery and Drug Development for Major Diseases GanzhouJiangxi341000Xi’anShaanxi 710032China School of Medicine Shanghai UniversityShanghai 200444China

CD8^(+)T-cell exhaustion is a state of dysfunction that promotes tumor progression and is marked by the generation of Slamf6^(+)progenitor exhausted(Tex^(prog))and Tim-^(3+)terminally exhausted(Tex^(term))*** of DNA binding protein 2(Id2)has been shown to play important roles in T-cell development and CD8^(+)T-cell ***,the role of Id2 in CD8^(+)T-cell exhaustion is ***,we found that Id2 transcriptionally and epigenetically regulates the generation of Texprog cells and their conversion to Texterm *** deletion of Id2 dampens CD8^(+)T-cell-mediated immune responses and the maintenance of stem-like CD8^(+)T-cell subpopulations,suppresses PD-1 blockade and increases tumor ***,through its HLH domain,Id2 binds and disrupts the assembly of the Tcf3-Tal1 transcriptional regulatory complex,and thus modulates chromatin accessibility at the Slamf6 promoter by preventing the interaction of Tcf3 with the histone lysine demethylase ***,Id2 increases the abundance of the permissive H3K4me2 mark on the Tcf3-occupied E-boxes in the Slamf6 promoter,modulates chromatin accessibility at the Slamf6 promoter and epigenetically regulates the generation of Slamf6+Texprog *** LSD1 inhibitor GSK2879552 can rescue the Id2 knockout phenotype in tumor-bearing *** of LSD1 increases the abundance of Slamf6^(+)Tim-3^(−)Tex^(prog) cells in tumors and the expression level of Tcf1 in Id2-deleted CD8+T *** study demonstrates that Id2-mediated transcriptional and epigenetic modification drives hierarchical CD8^(+)T-cell exhaustion,and the mechanistic insights gained may have implications for therapeutic intervention with tumor immune evasion.

关键词： Id2 T-cell exhaustion Epigenetic modification Immune evasion