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Sliding Mode Fault Tolerant Attitude Control Scheme for Spacecraft with Actuator Faults

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Transactions of Nanjing University of Aeronautics and Astronautics 2019年第1期36卷 119-127页

作者： CAO Teng GONG Huajun han Bing College of Automation Engineering Nanjing University of Aeronautics and Astronautics

An active fault tolerant control scheme is investigated for the attitude control systems of spacecraft with external disturbance and actuator faults by using the sliding mode technique. Firstly,the dynamic equations and kinematic equations of spacecraft are given. For the dynamic mode of spacecraft in faulty case,a fault diagnosis component is used for fault detection and estimation by using a nonlinear observer. According to the fault estimation information obtained during the fault diagnosis,the fault tolerant control scheme is developed by adopting the backstepping sliding mode control technique. Meanwhile,the Lyapunov theory is used to analyze the stability of the closed-loop attitude systems. Finally,simulation results for the attitude dynamics models show the feasibility of the proposed fault tolerant scheme.

关键词： fault tolerant control fault estimation actuator faults sliding mode control

外源激素对紫花苜蓿种子内生根瘤菌增殖及幼苗生长的影响

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草业学报 2025年第2期34卷 81-93页

作者：杜媛媛康文娟师尚礼韩宜霖何富强甘肃农业大学草业学院草业生态系统教育部重点实验室中-美草地畜牧业可持续发展研究中心甘肃兰州730070

紫花苜蓿根瘤的形成发育及幼苗生长受到多重植物激素的调控。激素对外源根瘤菌的增殖和促生效应已有研究,但激素对内生根瘤菌的增殖及促生效应研究较少。因此,筛选出对根瘤菌SM12531f生长有促进作用的3-吲哚乙酸、6-苄氨基嘌呤和28-高... 详细信息

紫花苜蓿根瘤的形成发育及幼苗生长受到多重植物激素的调控。激素对外源根瘤菌的增殖和促生效应已有研究,但激素对内生根瘤菌的增殖及促生效应研究较少。因此,筛选出对根瘤菌SM12531f生长有促进作用的3-吲哚乙酸、6-苄氨基嘌呤和28-高油菜素内酯的浓度,然后用这3种浓度分别浸泡含有青色荧光蛋白标记的内生根瘤菌SM12531f的苜蓿种子并种植,分析外源激素对苜蓿植株组织中内生根瘤菌数量、植株结瘤及植株生长的影响。结果表明,3-吲哚乙酸、6-苄氨基嘌呤和28-高油菜素内酯这3种激素的最适浓度分别为14 mg·L^(-1)、18 mg·L^(-1)和2.97 mg·L^(-1)。幼苗期对植株内生根瘤菌增殖、结瘤及生长有益的是6-苄氨基嘌呤和28-高油菜素内酯,且前者的促进效果更明显,前者内生根瘤菌在根部的定殖数量最多,在稀释100倍时定殖数量为1167 cfu·g^(-1)、地上鲜重为1.99 g·株^(-1)。同样在分枝期对植株有益的是6-苄氨基嘌呤,且内生根瘤菌在根部研磨液稀释100倍时定殖数量为833 cfu·g^(-1)、地上鲜重为5.03 g·株^(-1)。因此,对苜蓿内生根瘤菌增殖及苜蓿生长最适的激素是18 mg·L^(-1)的6-苄氨基嘌呤,该发现对精准利用种子内生根瘤菌的结瘤固氮效应提供理论依据,为紫花苜蓿-根瘤菌共生育种奠定了基础。

关键词：内生根瘤菌增殖促生生长素细胞分裂素油菜素内固醇

Treatment of CD20-directed Chimeric Antigen Receptor-modified T cells in patients with relapsed or refractory B-cell non-Hodgkin lymphoma:an early phase IIa trial report

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Signal Transduction and Targeted Therapy 2016年第1期1卷 131-139页

作者： Wen-ying Zhang Yao Wang Ye-lei Guo han-ren Dai Qing-ming Yang Ya-jing Zhang Yan Zhang Mei-xia Chen Chun-meng Wang Kai-chao Feng Su-xia Li Yang Liu Feng-xia Shi Can Luo Wei-dong han Biotherapeutic Department Chinese PLA General HospitalBeijingChina Department of Immunology Institute of Basic MedicineSchool of Life SciencesChinese PLA General HospitalBeijingChina Department of Geriatric Hematology Chinese PLA General HospitalBeijingChina

Patients with relapsed or refractory non-Hodgkin lymphoma have a dismal *** Antigen Receptor(CAR)-modified T cells(CART cells)that targeted CD20 were effective in a phase I clinical trial for patients with advanced B-cell *** performed a phase IIa trial to further assess the safety and efficacy of administering autologous anti-CD20 CART(CART-20)cells to patients with refractory or relapsed CD20^(+)B-cell *** patients were enrolled,and seven patients underwent cytoreductive chemotherapy to debulk the tumors and deplete the lymphocytes before receiving T-cell *** overall objective response rate was 9 of 11(81.8%),with 6 complete remissions(CRs)and 3 partial remissions;no severe toxicity was *** median progression-free survival lasted for 46 months,and 1 patient had a 27-month continuous CR.A significant inverse correlation between the levels of the CAR gene and disease recurrence or progression was ***,the lesions in special sites,specifically the spleen and testicle,were refractory to CART-20 ***,these results together with our data from phase I strongly demonstrated the feasibility and efficacy of CART-20 treatment in lymphomas and suggest large-scale patient recruitment in a future *** study was registered at *** as NCT01735604.

关键词： patients lymphoma Antigen

Riemann Problem for a Geometrical Optics System

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Acta Mathematica Sinica,English Series 2014年第11期30卷 1846-1860页

作者： han Chun YANG Hong Jun CHENG Department of Mathematics Yunnan University

The paper solves analytically the Riemann problem for a nonstrictly hyperbolic system of conservation laws arising in geometrical optics,in which the flux contains the nonconvex function possessing an infinite number of inflection ***,the generalized Rankine–Hugoniot relations and entropy condition of delta shock waves and left（right）-contact delta shock waves are proposed and ***,with the help of the convex hull,seven kinds of structures of Riemann solutions are *** solutions fall into three broad categories with a series of geometric structures involving simultaneously contact discontinuities,vacuums and delta shock ***,numerical experiments confirm the theoretical analysis.

关键词： Geometrical optics Riemann problem delta shock wave vacuum convex hull

Sequential feasible optimal power flow in power systems

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Science China(Technological Sciences) 2009年第2期52卷 429-435页

作者： ZhenXiang han QuanYuan Jiang YiJia Cao 1. College of Electrical Engineering Zhejiang University Hangzhou 310027 China

A sequential feasible optimal power flow (OPF) method is developed for large-scale power systems. One of the outstanding features of this method is that it can maintain feasibility for both equality and inequality constraints during iterations. In sequential feasible OPF, every iteration consists of two stages: Objective improving stage and feasibility enforcing stage. Analytical basis for each stage is provided. Numerical studies on various power systems up to 2383 buses indicate that the proposed feasible approach is promising. Compared with the conventional OPF algorithms, such as interior point method, the proposed sequential feasible OPF approach can be terminated at any iteration and yield a feasible operating point simultaneously.

关键词： optimal power flow sequential feasible solution interior point method near binding

Effect of epidemic diseases on wild animal conservation

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Integrative Zoology 2023年第6期18卷 963-980页

作者： Bin HU Shuyi han Hongxuan HE National Research Center for Wildlife-Borne Diseases Institute of ZoologyChinese Academy of SciencesBeijingChina College of Life Sciences University of Chinese Academy of SciencesBeijingChina

Under the background of global species extinction,the impact of epidemic diseases on wild animal protection is increasingly ***,we review and synthesize the literature on this topic,and discuss the relationship between diseases and *** usually reduce species diversity by decreasing or extinction of species populations,but also accelerate species evolution and promote species *** the same time,species diversity can regulate disease outbreaks through dilution or amplification *** synergistic effect of human activities and global change is emphasized,which further aggravates the complex relationship between biodiversity and ***,we emphasize the importance of active surveillance of wild animal diseases,which can protect wild animals from potential diseases,maintain population size and genetic variation,and reduce the damage of diseases to the balance of the whole ecosystem and human ***,we suggest that a background survey of wild animal populations and their pathogens should be carried out to assess the impact of potential outbreaks on the population or species *** mechanism of dilution and amplification effect between species diversity and diseases of wild animals should be further studied to provide a theoretical basis and technical support for human intervention measures to change *** importantly,we should closely combine the protection of wild animals with the establishment of an active surveillance,prevention,and control system for wild animal epidemics,in an effort to achieve a win-win situation between wild animal protection and disease control.

关键词： active surveillance amplification effect dilution effect disease spillover wild animal protection

Land-use changes in the small watershed of the Loess Plateau,hilly-gully region, China

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Journal of Forestry Research 2015年第1期26卷 91-99页

作者： Yini han Jianzhi Niu Feizhou Wu Key Laboratory of Soil and Water Conservation & Desertification Combating Beijing Forestry University

As more and more farmland is converted to forestry, the need for effective decision support regarding the use of land in the fragile ecological environment of the Loess Plateau hilly-gully area. The Luoyugou watershed was chosen as the study area to calculate the single dynamic degree, integrated dynamic degree, and change indexes of land use, as well as the land-use type transition matrix. This was done by interpreting the TM and SPOT images of the Luoyugou watershed in 1986, 1995, and2004 and making statistical analysis. The results of ou statistical analysis show that the conversion of slope farm land to terrace and forest land plays a dominant role in land-use changes in the Luoyugou watershed from 1986 to2004. The land-use changes are mainly driven by popula tion growth, socio-economic development, consume spending, and investment in forest ecology.

关键词： Loess Plateau hilly-gully region Luoyugou watershed Land use and cover changes Driving force

基于德尔菲法的全科住院医师临床思维能力评价体系构建研究

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中国全科医学 2025年第1期28卷 77-82页

作者：宋一帆韩庆烽肖卫忠杨振华北京大学第三医院全科医学科北京市100191 北京大学第三医院肾内科北京市100191 北京大学第三医院神经内科北京市100191

背景全科医学的临床思维基于全科医学专业的自身特点,有其独特性,要求全科医师具备“以患者为中心”的临床诊断和治疗技能。为了更好地反映出全科临床住院医师的临床思维能力,需要建立一套完善的、可以反映出其全方面能力的有效评价标准... 详细信息

背景全科医学的临床思维基于全科医学专业的自身特点,有其独特性,要求全科医师具备“以患者为中心”的临床诊断和治疗技能。为了更好地反映出全科临床住院医师的临床思维能力,需要建立一套完善的、可以反映出其全方面能力的有效评价标准,目前尚无适用于衡量全科住院医师临床思维能力的评价体系。目的通过德尔菲法(Delphi法)构建全科住院医师以岗位胜任力为导向的临床思维能力评价体系。方法2021年12月—2022年2月,本课题组基于文献研究初步构建了全科住院医师临床思维能力指标体系框架,运用Delphi法,与12位专家进行了两轮深入沟通,就指标的重要性给出客观评估,筛选出合适的指标,并运用层次分析法确定每个指标的权重。结果通过两轮专家咨询,本课题组建立了一个综合性的评估体系,其中包括5个一级指标(临床知识学习和扩展、资料收集和利用、诊断分析和利用、治疗决策能力、沟通和合作能力)以及30个二级指标。两轮咨询问卷有效回收率达到100.0%,专家权威系数为0.85,一级和二级指标的专家协调系数分别达到了0.299和0.189(P<0.01),一级指标的权重分别为0.198、0.198、0.227、0.227、0.150。结论本研究使用Delphi法建立一个全面评价住院医师临床思维能力的评估体系。经过对结果数据分析可知该评估体系具有较高的权威性和科学性,为今后培养高质量全科住院医师,提升全科医学教学质量提供了参考。

关键词：全科医学临床思维能力评价体系全科住院医师德尔菲法

Modification of diphenylamine-linked bis(oxazoline) ligands: Tuning of electronic effect and rigidity of ligand skeleton

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Science China Chemistry 2009年第9期52卷 1321-1330页

作者： LIU han LI Wei DU DaMing Beijing National Laboratory for Molecular Sciences(BNLMS) and Key Laboratory of Bioorganic Chemistry and Molecular EngineeringCollege of Chemistry and Molecular EngineeringPeking UniversityBeijing 100871China School of Chemical Engineering and Environment Beijing Institute of TechnologyBeijing 100081China

The electronic effect of diphenylamine-linked bis(oxazoline) ligands was tuned through introduction of electron-withdrawing bromo and nitro substituents onto the 4 and 4′ position. The variation of the NH bond acidity was determined by the different chemical shifts of NH. The catalytic activity and enantioselectivity of the modified ligands were tested in the asymmetric Friedel-Crafts alkylation of indole with β-nitrostyrene. The effect of ligand skeleton rigidity was also investigated through the synthesis of iminodibenzyl-linked bis(oxazoline) ligands and evaluation of their catalytic activity in Friedel-Crafts alkylation.

关键词： asymmetric catalysis electronic effect bis(oxazoline) Friedel-Crafts alkylation