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Guidance, Navigation and Control 2023年第3期3卷 47-64页

作者： Bingbing Liu Hai Yu Shizhen Wu xiao Liang yongchun Fang College of Artificial Intelligence Nankai University Tianjin 300350P.R.China

The unmanned dual-arm aerial manipulator system is composed of a multirotor unmanned aerial vehicle(UAV)and two *** to a single manipulator,dual-arm always provides greater°exibility and versatility in both goods delivery and complex task ***,the practical application of the system is limited due to nonlinearities and complex dynamic coupling behavior between the multirotor and the manipulator,as well as the one between the inner and outer loop of the *** this paper,a holistic model of the dual-arm aerial manipulator system is¯rst derived with complete model ***,an adaptive sliding-mode disturbance observer(ASMDO)is proposed to handle external disturbances and unmeasurable disturbances caught by unmeasurable angular velocity and acceleration of the ***,for safety concerns and transient performance requirements,the state constraints should be *** this end,an auxiliary term composed of constrained variable signals is ***,the performance of the designed method is proven by rigorous ***,the proposed method is validated through two sets of simulation tests.

关键词： Unmanned dual-arm aerial manipulator adaptive sliding-mode disturbance observer state constraint

Secondary aerosol formation and oxidation capacity in photooxidation in the presence of Al_2O_3 seed particles and SO_2

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Science China Chemistry 2015年第9期58卷 1426-1434页

作者： Biwu Chu Tengyu Liu xiao Zhang yongchun Liu Qingxin Ma Jinzhu Ma Hong He Xinming Wang Junhua Li Jiming Hao State Key Joint Laboratory of Environment Simulation and Pollution Control Research Center for Eco-Environmental Sciences Chinese Academy of Sciences State Key Laboratory of Organic Geochemistry Guangzhou Institute of Geochemistry Chinese Academy of Sciences School of Environment Tsinghua University Nanjing University of Information Science & Technology

To investigate the sensitivity of secondary aerosol formation and oxidation capacity to NOx in homogeneous and heterogeneous reactions, a series of irradiated toluene/NOx/air and ?-pinene/NOx/air experiments were conducted in smog chambers in the absence or presence of Al2O3 seed particles. Various concentrations of NOx and volatile organic compounds(VOCs) were designed to simulate secondary aerosol formation under different scenarios for NOx. Under "VOC-limited" conditions, the increasing NOx concentration suppressed secondary aerosol formation, while the increasing toluene concentration not only contributed to the increase in secondary aerosol formation, but also led to the elevated oxidation degree for the organic aerosol. Sulfate formation was suppressed with the increasing NOx due to a decreased oxidation capacity of the photooxidation system. Secondary organic aerosol(SOA) formation also decreased with the presence of high concentration of NOx, because organo-peroxy radicals(RO2) react with NOx instead of with peroxy radicals(RO2 or HO2), resulting in the formation of volatile organic products. The increasing concentration of NOx enhanced the formation of sulfate, nitrate and SOA under "NOx-limited" conditions, in which the heterogeneous reactions played an important role. In the presence of Al2O3 seed particles, a synergetic promoting effect of mineral dust and NOx on secondary aerosol formation in heterogeneous reactions was observed in the photooxidation. This synergetic effect strengthened the positive relationship between NOx and secondary aerosol formation under "NOx-limited" conditions but weakened or even overturned the negative relationship between NOx and secondary aerosol formation under "VOC-limited" conditions. Sensitivity of secondary aerosol formation to NOx seemed different in homogeneous and heterogeneous reactions, and should be both taken into account in the sensitivity study. The sensitivity of secondary aerosol formation to NOx was further

关键词： secondary aerosol oxidation capacity synergetic promoting effect Al2O3 seed particles sensitivity

Kinetic Parameters of Methane Generated from Source Rocks in the Kuqa Depression of Tarim Basin and Their Application

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Acta Geologica Sinica(English Edition) 2008年第1期82卷 154-163页

作者： LI Xianqing xiao Xianming MI Jingkui TANG yongchun xiao Zhongyao LIU Dehan SHEN Jiagui YANG Yunfeng WANG Yan DONG Peng State Key Laboratory of Organic Geochemistry Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou 510640 China State Key Laboratory of Coal Resources and Safe Mining China University of Mining and Technology Beijing 100083 China Research Center of Petroleum Energy and Environment California Institute of Technology 21910 Currier Rd Walnut CA 61769 USA Research Institute of Exploration and Development Tarim Oil Field Company PetroChina Korla Xinjiang 841000 China

In a thermal simulation experiment of gold tubes of closed-system, calculating with the KINETICS and GOR-ISOTOPE KINETICS software, kinetic parameters of gas generation and methane carbon isotopic fractionation from Triassic-Jurassic hydrocarbon source rocks in the Kuqa depression of Tarim Basin are obtained. The activation energies of methane generated from Jurassic coal, Jurassic mudstone and Triassic mudstone in the Kuqa Depression are 197-268 kJ/mol, 180-260 kJ/mol and 214-289 kJ/mol, respectively, and their frequency factors are 5.265×10^13 s^-1, 9.761×10^11 s^-1 and 2.270×10^14 s^-1. This reflects their differences of hydrocarbon generation behaviors. The kinetic parameters of methane carbon isotopic fractionation are also different in Jurassic coal, Jurassic mudstone and Triassic mudstone, whose average activation energies are 228 kJ/mol, 205 kJ/mol and 231 kJ/mol, respectively. Combined with the geological background, the origin of natural gas in the Yinan-2 gas pool is discussed, and an accumulation model of natural gas is thus established. The Yinan- 2 gas is primarily derived from Jurassic coal-bearing source rocks in the Yangxia Sag. Main gas accumulation time is 5-0 Ma and the corresponding Ro is in the range from 1.25 %-1.95 %. The loss rate of natural gas is 25 %-30 %.

关键词： hydrocarbon source rock methane generation carbon isotopic fractionation kinetics Kuqa Depression Tarim Basin

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基于分块优化思想的多无人机覆盖路径规划

中国科学：技术科学 2020年第4期50卷 439-452页

作者：肖玉婷方勇纯梁潇林河何桢南开大学机器人与信息自动化研究所天津市智能机器人技术重点实验室天津300350

覆盖路径规划广泛应用于环境清洁、建图、监控等场景,为了提高覆盖效率,经验证,一组有自主运动能力的无人飞行器配合机载传感器可以提供有效帮助.本文提出一种可以应用于大规模复杂环境的多无人飞行器覆盖路径规划方法.在面积规模大、... 详细信息

覆盖路径规划广泛应用于环境清洁、建图、监控等场景,为了提高覆盖效率,经验证,一组有自主运动能力的无人飞行器配合机载传感器可以提供有效帮助.本文提出一种可以应用于大规模复杂环境的多无人飞行器覆盖路径规划方法.在面积规模大、环境情况复杂的区域内,计算出可以采集到精确可靠环境信息的最优覆盖路径是比较困难的,本文提出的覆盖路径规划方法基于分块优化的思想,将大规模的环境分成若干面积较小的子区域,分别计算子区域内的局部最优覆盖路径,在一些特定的约束条件下,所有子区域内的局部覆盖路径可以连接成一条遍历环境中每个子区域的整体覆盖路径,兼顾了环境的差异性和覆盖的完整性.同时,为了保证整体路径的平滑,适合飞行器跟踪,在规划路径时还考虑到减小相邻两段局部路径之间的过度转角和飞行器完成一次环境覆盖的调头转向次数,通过设计不同的覆盖模式以及在计算局部路径的评价函数中加入转角相关项来实现路径的平滑.最后,通过仿真和实验验证了所提算法的有效性和可行性.

关键词：分块优化多无人机环境覆盖路径规划

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一种两自由度飞行机械臂系统的设计与实现

航空学报 2021年第2期42卷 258-268页

作者：何慰方勇纯梁潇张鹏南开大学机器人与信息自动化研究所天津300350 天津市智能机器人技术重点实验室天津300350

提出了一种基于欧拉-拉格朗日方法的飞行机械臂系统模型,在机械臂缓慢运动的合理假设下,模型不仅能有效描述实际系统,同时模型表达得到了精简。在此基础上进行控制器设计,首先使用输出变换将系统反馈线性化,并将内外环动态分离,基于此... 详细信息

提出了一种基于欧拉-拉格朗日方法的飞行机械臂系统模型,在机械臂缓慢运动的合理假设下,模型不仅能有效描述实际系统,同时模型表达得到了精简。在此基础上进行控制器设计,首先使用输出变换将系统反馈线性化,并将内外环动态分离,基于此分别设计外环滑模控制器和内环比例-积分-微分(PID)控制器。该控制器在仿真实验中能有效抑制机械臂带来的扰动且镇定和轨迹跟踪性能明显优于经典的串级比例-积分-微分控制器。结果表明本文提出的建模和控制方法能够有效补偿机械臂的已建模扰动,并能充分抑制机械臂摆动产生的未建模扰动,且控制器计算复杂度适中,能够满足实际应用需求。

关键词：无人机机械臂动力学建模非线性控制运动控制

Essential roles of exosome and circRNA_101093 on ferroptosis desensitization in lung adenocarcinoma

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Cancer Communications 2022年第4期42卷 287-313页

作者： xiao Zhang Yunhua Xu Lifang Ma Keke Yu Yongjie Niu Xin Xu Yi Shi Susu Guo Xiangfei Xue Yikun Wang Shiyu Qiu Jiangtao Cui Hong Wang xiaoting Tian Yayou Miao Fanyu Meng Yongxia Qiao yongchun Yu Jiayi Wang Department of Laboratory Medicine Shanghai Chest HospitalShanghai Jiao Tong University School of MedicineShanghai 200030P.R.China Department of Thoracic Surgery Shanghai Chest HospitalShanghai Jiao Tong University School of MedicineShanghai 200030P.R.China Shanghai Institute of Thoracic Oncology Shanghai Chest HospitalShanghai Jiao Tong University School of MedicineShanghai 200030P.R.China Shanghai Lung Cancer Center Shanghai Chest HospitalShanghai Jiao Tong University School of MedicineShanghai 200030P.R.China Department of Bio-bank Shanghai Chest HospitalShanghai Jiao Tong University School of MedicineShanghai 200030P.R.China Shanghai Municipal Hospital of Traditional Chinese Medicine Shanghai University of Traditional Chinese MedicineShanghai 200071P.R.China Bio-X Institutes Key Laboratory for the Genetics of Developmental and Neuropsychiatric disorderShanghai Jiao Tong UniversityShanghai 200030P.R.China Department of Clinical Laboratory Medicine Shanghai Tenth People’s Hospital of Tongji UniversityShanghai 200072P.R.China School of Public Health Shanghai Jiao Tong University School of MedicineShanghai 200025P.R.China

Background:Resistance to ferroptosis,a regulated cell death caused by irondependent excessive accumulation of lipid peroxides,has recently been linked to lung adenocarcinoma(LUAD).Intracellular antioxidant systems are required for protection against *** purpose of the present studywas to investigate whether and how extracellular system desensitizes LUAD cells to ***:Established human lung fibroblasts MRC-5,WI38,and human LUAD H1650,PC9,H1975,H358,A549,and H1299 cell lines,tumor and matched normal adjacent tissues of LUAD,and plasma from healthy individuals and LUAD patients were used in this *** and immunoblotting were used to analyze protein expression,and quantitative reverse transcription-PCR was used to analyze mRNA *** viability,cell death,and the lipid reactive oxygen species generationwere measured to evaluate the responses to *** were observed using transmission electron *** localization of arachidonic acid(AA)was detected using click chemistry labeling followed by confocal *** between RNAs and proteins were detected using RNA pull-down,RNA immunoprecipitation and photoactivatable ribonucleoside-enhanced crosslinking and immunoprecipitation *** analysis was used to investigate RNA-regulated proteins,and metabolomic analysis was performed to analyze *** xenograft,patient-derived xenograft,cell-implanted intrapulmonary LUAD mouse models and plasma/tissue specimens from LUAD patients were used to validate the molecular ***:Plasma exosome from LUAD patients specifically reduced lipid peroxidation and desensitized LUAD cells to ferroptosis.A potential explanation is that exosomal circRNA_101093(cir93)maintained an elevation in intracellular cir93 in LUAD to modulate AA,a poly-unsaturated fatty acid critical for ferroptosisassociated increased peroxidation in the plasma ***,cir93 interac

关键词： exosome circRNA_101093 ferroptosis desensitization lung adenocarcinoma lipid peroxidation poly-unsaturated fatty acid taurine N-arachidonoyl taurine RNA-protein interaction

MMC-UPQC在RTDS仿真中的脉冲输入方案设计

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电测与仪表 2019年第9期56卷 104-109页

作者：杨用春肖湘宁袁敞新能源电力系统国家重点实验室(华北电力大学) 河北保定071003

统一电能质量控制器(UPQC)装置投入现场运行之前,开展基于实时数字仿真器(RTDS)的实验是非常重要的一步,不仅能够使UPQC控制器的功能和性能得到较为充分的验证,还可以积累经验为后续的物理实验提供重要的指导和借鉴。基于模块化多电平... 详细信息

统一电能质量控制器(UPQC)装置投入现场运行之前,开展基于实时数字仿真器(RTDS)的实验是非常重要的一步,不仅能够使UPQC控制器的功能和性能得到较为充分的验证,还可以积累经验为后续的物理实验提供重要的指导和借鉴。基于模块化多电平换流器(MMC)结构的UPQC由于模块数较多,需要触发的IGBT很多,为了合理利用RTDS宝贵的资源,在开展RTDS实验的时候,必须要对资源分配进行优化设计,其中脉冲的输入方案就是其中的一个重要环节。文章在分析MMC-UPQC的拓扑结构的基础之上,首先对RTDS及UPQC的物理控制器的结构和需求进行了梳理和分析,然后给出了两种脉冲输入方案并进行了对比分析,最后在RTDS平台上开展了数字-物理闭环仿真实验,实验结果验证了所给脉冲编码方案的可行性。

关键词： MMC-UPQC RTDS 控制器脉冲编码数字-物理混合仿真

Oil cracking to gases: Kinetic modeling and geological significance

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Chinese Science Bulletin 2006年第22期51卷 2763-2770页

作者： TIAN Hui 1,2 WANG Zhaoming xiao Zhongyao LI Xianqing xiao Xianming State Key Laboratory of Organic Geochemistry Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou 510640 China Graduate School of the Chinese Academy of Sciences Beijing 100049China Tarim Oil Field Company Korla 841000 China Key Laboratory of Coal Resources Ministry of Education ChinaUniversity of Mining and Technology Beijing 100083 China

从 Tarim 盆的 LN14 的一件三叠纪的油样品是用在在 50 MPa 的恒压下面的 200-620 deg C 的封上的金试管的 pyrolyzed。气体并且剩余可溶的烃被分析。结果证明到气体的石油的裂化能被划分成二个不同阶段：从液体油的全部的 C1-5 气体的... 详细信息

从 Tarim 盆的 LN14 的一件三叠纪的油样品是用在在 50 MPa 的恒压下面的 200-620 deg C 的封上的金试管的 pyrolyzed。气体并且剩余可溶的烃被分析。结果证明到气体的石油的裂化能被划分成二个不同阶段：从液体油的全部的 C1-5 气体的主要产生由 C2-5 烃和 secondary 或到甲烷的 C2-5 气体的进一步的裂开的优势描绘了导致气体的进步的干的 andcarbon 富有的事。基于试验性的数据，运动参数为主要产生和第二等的石油的裂化裂化气被决定并且外推到地质的条件预言热稳定性和原油的裂开的程度。最后，为原油的热破坏的一个进化模型被建议，它到油裂化气的迁居和累积的含意被讨论。

关键词：石油裂化动态建模石油热稳定性气体积累

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中国西部城市网络拓扑结构演化及结构效应

经济地理 2023年第4期43卷 51-62页

作者：杨亮洁俞啸杨永春潘竟虎西北师范大学地理与环境科学学院甘肃兰州730070 西北师范大学甘肃省绿洲资源环境与可持续发展重点实验室甘肃兰州730070 兰州大学资源环境学院甘肃兰州730000 兰州大学西部环境教育部重点实验室甘肃兰州730000

城市网络是城市社会经济活动联系的空间表达,城市网络结构演变机制及结构效应的研究对区域协调发展具有重要意义。文章以中国西部131个地级及以上城市为研究区,基于中国500强企业数据、百度搜索指数数据构建城市网络,采取“点—线—网... 详细信息

城市网络是城市社会经济活动联系的空间表达,城市网络结构演变机制及结构效应的研究对区域协调发展具有重要意义。文章以中国西部131个地级及以上城市为研究区,基于中国500强企业数据、百度搜索指数数据构建城市网络,采取“点—线—网”的研究模式分析中国西部城市网络拓扑结构时空演化机制及结构效应。结果表明:(1)不同要素流下城市网络拓扑结构差异性和相似性并存;中国西部城市网络集聚特征显著,均衡性较差但略有增加。(2)2010—2020年中国西部城市网络呈现密集化趋势,城市网络联系的广度和深度显著增强,处于快速增长阶段。(3)择优链接机制是城市网络演化的核心驱动机制;路径依赖机制是塑造城市网络结构的主要驱动力。(4)不同要素流下城市网络均存在显著的“马太效应”,匹配效应和“富人俱乐部”现象差异显著,基于企业组织链的城市网络中异配效应较为显著,基于信息流的城市网络中同配效应较显著。

关键词：城市网络网络拓扑结构演化机制结构效应百度搜索指数中国500强企业中国西部

基于模块化多电平变流器的统一电能质量调节器工程实验装置研究

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电工技术学报 2018年第16期33卷 3743-3755页

作者：杨用春肖湘宁郭世枭高亚静张波分布式储能与微网河北省重点实验室(华北电力大学) 保定071003 新能源电力系统国家重点实验室(华北电力大学) 北京102206

将模块化多电平变流器(MMC)技术和统一电能质量调节器(UPQC)相结合,为将UPQC应用于高电压、大容量的场合提供了可能,为电能质量问题的集中解决提供了新的思路。研究MMC型UPQC具有重要的技术意义和市场价值。首先分析基于MMC的UPQC工作原... 详细信息

将模块化多电平变流器(MMC)技术和统一电能质量调节器(UPQC)相结合,为将UPQC应用于高电压、大容量的场合提供了可能,为电能质量问题的集中解决提供了新的思路。研究MMC型UPQC具有重要的技术意义和市场价值。首先分析基于MMC的UPQC工作原理,对其关键参数进行分析设计,针对UPQC并联侧和串联侧MMC变流器的电能质量补偿功能提出相应的控制策略。PSCAD/EMTDC下的仿真结果证明了参数设计的正确性和控制策略的有效性。进而研制一套4MV·A/10kV的MMC型UPQC工程实验装置,开展现场实验并进行分析,实验结果表明MMC型的UPQC能够实现多种电能质量的综合补偿。

关键词：模块化多电平变流器统一电能质量调节器参数设计控制策略工业样机