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Underactuated spacecraft angular velocity stabilization and three-axis attitude stabilization using two single gimbal control moment gyros

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Acta Mechanica Sinica 2010年第2期26卷 279-288页

作者： lei jin shijie xu department of guidance Navigation and Control School of Astronautics Beihang University 100191 Beijing China

Angular velocity stabilization control and attitude stabilization control for an underactuated spacecraft using only two single gimbal control moment gyros （SGCMGs） as actuators is investigated. First of all, the dynamic model of the underactuated spacecraft is established and the singularity of different configurations with the two SGCMGs is analyzed. Under the assumption that the gimbal axes of the two SGCMGs are installed in any direction, and that the total system angular momentum is not zero, a state feedback control law via Lyapunov method is designed to globally asymptotically stabilize the angular velocity of spacecraft. Under the assumption that the gimbal axes of the two SGCMGs are coaxially installed along anyone of the three principal axes of spacecraft inertia, and that the total system angular momentum is zero, a discontinuous state feedback control law is designed to stabilize three-axis attitude of spacecraft with respect to the inertial frame. Furthermore, the singularity escape of SGCMGs for the above two control problems is also studied. Simulation results demonstrate the validity of the control laws.

关键词： Single gimbal control moment gyro ·Undcractuated spacecraft · Angular velocity stabilization · Three-axis attitude stabilization·Singularity

controllability of an underactuated spacecraft with one thruster under disturbance

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Acta Mechanica Sinica 2012年第3期28卷 838-847页

作者： Dong-Xia Wang Ying-Hong Jia lei jin Hai-Chao Gui Shi-Jie xu department of guidance Navigation and ControlSchool of AstronauticsBeihang University100191 BeijingChina

For an underactuated spacecraft using only one thruster, the attitude controllability with respect to the or- bit frame is studied in the presence of periodical oscillation disturbance, which provides a preconditional guide on de- signing control law for underactuated attitude control sys- tem. Firstly, attitude dynamic model was established for an underactuated spacecraft, and attitude motion was described using the special orthogonal group （SO （3））. Secondly, Liou- ville theorem was used to confirm that the flow generated by the drift vector of the underactuated attitude control system is volume-preserving. Furthermore, according to Poincar6＇s re- currence theorem, we draw conclusions that this drift field is weakly positively poisson stable （WPPS）. Thirdly, the suffi- cient and necessary condition of controllability was obtained on the basis of lie algebra rank condition （LARC）. Finally, the controllable conditions were analyzed and simulated in different cases of inertia matrix with the installed position of thruster.

关键词： Underactuated spacecraft Periodical oscilla-tion disturbance. controllability. Weakly positively poissonstable ~ Lie algebra

Differential diagnosis of coronavirus disease 2019 from community-acquired-pneumonia by computed tomography scan and follow-up

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Infectious Diseases of Poverty 2020年第4期9卷 164-164页

作者： Kai-Cai Liu Ping xu Wei-Fu Lv lei Chen Xiao-Hui Qiu jin-Long Yao jin-Feng Gu Bo Hu Wei Wei Infection Hospital Anhui Provincial Hospitalthe First Affiliated Hospital of USTCDivision of Life Sciences and MedicineUniversity of Science and Technology of ChinaHefei230022Anhui ProvinceChina department of Respiratory Hefei Second People’s HospitalHefei Hospital Affiliated to Anhui Medical University1 Guangde RoadHefei230011Anhui ProvinceChina department of Radiology Anhui Provincial Hospitalthe First Affiliated Hospital of USTCDivision of Life Sciences and MedicineUniversity of Science and Technology of China4 Lujiang RoadHefei230001Anhui ProvinceChina department of Radiology Fuyang Second People’s Hospital450 Linquan RoadYingzhou DistrictFuyang236015Anhui ProvinceChina department of Radiology Bo Zhou People’s Hospital3 Xiyi AvenueQiaocheng DistrictBozhou236800Anhui ProvinceChina department of Radiology Tongling People’s Hospital468 Bijiashan RoadTongling244000Anhui ProvinceChina department of Radiology Fuyang sixth People’s Hospital2019 Huai He RoadFuyang236015Anhui ProvinceChina

Objective Coronavirus disease 2019(COVID-19)is currently the most serious infectious disease in the *** accurate diagnosis of this disease in the clinic is very *** study aims to improve the differential ability of computed tomography(CT)to diagnose COVID-19 and other community-acquired pneumonias(CAPs)and evaluate the short-term prognosis of these *** The clinical and imaging data of 165 COVID-19 and 118 CAP patients diagnosed in seven hospitals in Anhui Province,china from January 21 to February 28,2020 were retrospectively *** CT manifestations of the two groups were recorded and compared.A correlation analysis was used to examine the relationship between COVID-19 and age,size of lung lesions,number of involved lobes,and CT findings of *** factors that were helpful in diagnosing the two groups of patients were identified based on specificity and *** The typical CT findings of COVID-19 are simple ground-glass opacities(GGO),GGO with consolidation or grid-like *** sensitivity and specificity of the combination of age,white blood cell count,and ground-glass opacity in the diagnosis of COVID-19 were 92.7 and 66.1%,*** consolidation,fibrous cords,and bronchial wall thickening were used as indicators to exclude *** sensitivity and specificity of the combination of these findings were 78.0 and 63.6%,*** follow-up results showed that 67.8%(112/165)of COVID-19 patients had abnormal changes in their lung parameters,and the severity of the pulmonary sequelae of patients over 60 years of age worsened with *** Age,white blood cell count and ground-glass opacity have high accuracy in the early diagnosis of COVID-19 and the differential diagnosis from *** aged over 60 years with COVID-19 have a poor *** result provides certain significant guidance for the diagnosis and treatment of new coronavirus pneumonia.

关键词： Coronavirus disease 2019 Pneumonia Computed tomography X-ray Differential diagnosis

介入透视下注射聚多卡醇治疗海绵状血管瘤的临床观察

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国际医药卫生导报 2018年第19期24卷 2889-2891页

作者：王茂华徐磊张十一吴学君种振岳金星山东大学附属省立医院血管外科济南250021

目的观察介入透视下注射聚多卡醇治疗海绵状血管瘤的临床效果。方法回顾性分析2016年7月至2017年11月本院血管外科介入透视下注射聚多卡醇治疗的海绵状血管瘤27例（瘤体29个）的疗效。结果随访3～20个月，显效24例（瘤体26个），89．7％... 详细信息

目的观察介入透视下注射聚多卡醇治疗海绵状血管瘤的临床效果。方法回顾性分析2016年7月至2017年11月本院血管外科介入透视下注射聚多卡醇治疗的海绵状血管瘤27例（瘤体29个）的疗效。结果随访3～20个月，显效24例（瘤体26个），89．7％（26／29）的血管瘤基本或完全消退，有效2例（瘤体2个），无效1例（瘤体1个），总有效率达到96．6％（28／29）；发生并发症1例，经治疗后恢复。结论介入透视下注射聚多卡醇治疗海绵状血管瘤微创、安全、定位准确，疗效显著。

关键词：血管瘤介入透视聚多卡醇

社区家庭医生签约服务模式发展现况及对策分析

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中国社区医师 2021年第35期37卷 178-179页

作者：徐炜金璐刘杰陈佳俊吴诗悦张忻怡黄磊复旦大学附属肿瘤医院人力资源部上海200032

本文旨在阐述上海市家庭医生签约制的现状、问题与原因,从而为社区家庭医生签约服务模式推进作探索。使用文献分析法,通过查阅国内外相关文献,并与国外研究对照,阐述当前家庭医生签约制的现状、问题与原因。同时结合现有情况,提出参考... 详细信息

本文旨在阐述上海市家庭医生签约制的现状、问题与原因,从而为社区家庭医生签约服务模式推进作探索。使用文献分析法,通过查阅国内外相关文献,并与国外研究对照,阐述当前家庭医生签约制的现状、问题与原因。同时结合现有情况,提出参考性意见。上海市目前家庭医生“1+1+1”医疗机构组合已取得一定成效,对照文献资料仍可能存在家庭医生人才资源缺口大,社区居居民签约率低,宣传工作不到位等问题。可通过推进全科医生培养模式的改革,健全就业保障体系,加强宣传提高知晓和认同,加强舆论引导转变错误观念,加强推进分级诊疗,确保社区医院的转诊权。

关键词：家庭医生医改政策分级诊疗

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某舰艇官兵睡眠质量及情绪状态调查

职业与健康 2023年第3期39卷 359-363页

作者：王蒙蒙徐瑾王一浩韩易楼标雷中国人民解放军海军特色医学中心高压氧神经内科上海200052 海军军医大学附属长征医院神经内科上海200003 海军军医大学附属长征医院心理科上海200003

目的了解海军某部队舰艇官兵的睡眠质量和情绪状态,分析两者之间的相关性及影响因素,为舰艇官兵的身心健康保障提供参考依据。方法 2021年12月—2022年1月,采用随机抽样的方法选取394名我国东南沿海某海军部队舰艇官兵作为调查对象,分... 详细信息

目的了解海军某部队舰艇官兵的睡眠质量和情绪状态,分析两者之间的相关性及影响因素,为舰艇官兵的身心健康保障提供参考依据。方法 2021年12月—2022年1月,采用随机抽样的方法选取394名我国东南沿海某海军部队舰艇官兵作为调查对象,分别采用匹兹堡睡眠质量指数(Pittsburgh sleep quality index,PSQI)量表、广泛性焦虑障碍-7(generalized anxiety disorder-7,GAD-7)量表以及患者健康问卷-9(patient health questionnaire-9,PHQ-9)评估舰艇官兵的睡眠、焦虑及抑郁状态。结果 394名舰艇官兵中出现睡眠障碍(PSQI>7分)的共有166人,占42.13%,以主观睡眠时间短、入睡时间长、睡眠质量差及日间功能差为主;患有焦虑情绪(GAD-7≥5分)的有122人,占30.96%,患有抑郁情绪(PHQ-9≥5分)的有146人,占37.06%。此外,睡眠情况与官兵的年龄、军龄和舰龄有关(均P0.05);焦虑、抑郁情绪与官兵的年龄、军龄、舰龄、婚姻状况及军级别有关(均P0.05)。舰艇官兵的睡眠状况与焦虑、抑郁情绪均存在显著相关(均P<0.01)。结论某舰艇官兵普遍存在睡眠状态不佳、焦虑及抑郁等不良情绪;舰艇官兵的睡眠状况受官兵的年龄、军龄和舰龄的影响,且与焦虑、抑郁不良情绪呈显著相关性,提示在日后应保持对舰艇官兵(尤其是年龄较大、军龄和舰龄较长者)的生理及心理健康的同步关注。提倡开展睡眠指导、心理支持与干预,加强舰艇医疗服务建设,有利于维护舰艇官兵的身心健康。

关键词：舰艇官兵睡眠情绪量表

CartoSound指导下肥厚型梗阻性心肌病射频消融治疗

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中国心脏起搏与心电生理杂志 2021年第1期35卷 7-11页

作者：白瑾刘书旺冯新恒冯杰莉徐昕晔徐维陈少敏李蕾高炜北京大学第三医院心内科、血管医学研究所国家卫生健康委心血管分子生物学与调节肽重点实验室分子心血管学教育部重点实验室心血管受体研究北京市重点实验室北京100191

目的探讨心腔内超声(CartoSound)三维标测指导下射频消融室间隔治疗肥厚型梗阻性心肌病(HOCM)的安全性及疗效。方法在CartoSound三维标测技术指导下,对5例HOCM患者行经皮室间隔射频消融治疗,以收缩期二尖瓣瓣叶前向运动(SAM)对应的左室... 详细信息

目的探讨心腔内超声(CartoSound)三维标测指导下射频消融室间隔治疗肥厚型梗阻性心肌病(HOCM)的安全性及疗效。方法在CartoSound三维标测技术指导下,对5例HOCM患者行经皮室间隔射频消融治疗,以收缩期二尖瓣瓣叶前向运动(SAM)对应的左室室间隔部位作为消融靶点,应用Smartouch盐水灌注消融电极,消融能量35~40 W,冷盐水灌注流速20 mL/min,温度43℃,贴靠压力5~10 g,每次放电时间60 s。以左室流出道(LVOT)压力阶差下降50%或SAM区域心肌活动显著减弱作为消融有效终点。比较术前、术后LVOT压力阶差变化,记录围术期并发症发生情况,评价疗效和安全性。结果术中累计消融放电15~42次,消融范围占SAM区域比值22.9%~76.6%。术后即刻LVOT压力阶差由术前(105±93.6)mmHg下降至(40.6±37.2)mmHg(P<0.001)。随访至术后6个月,患者临床症状消失,心功能改善;术后6个月室间隔厚度由术前(16.1±2.9)mm下降至(13.3±2.4)mm(P=0.115);LVOT压力阶差由术前(105±93.6)mmHg逐步下降至(94.7±71.9)mmHg(术后7日,P=0.146)、(30.72±12.9)mmHg(术后1个月,P<0.01)、(19.4±17.8)mmHg(术后6个月,P<0.01)。5例患者均未出现手术并发症。结论经心腔内超声CartoSound指导下室间隔射频消融术治疗HOCM安全、有效。

关键词：心血管病学肥厚型梗阻性心肌病心腔内超声 CartoSound 三维标测射频消融

课程思政在医学生生物化学教学中的探索与实践

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医学教育研究与实践 2020年第4期28卷 637-640页

作者：史秀娟金彩霞田海滨李姣张陈徐磊吕立夏同济大学医学院生物化学教研室上海200092

高校立身之本在于立德树人。长期以来,高校教师注重了对学生的知识传授而忽视了价值引领,导致全员、全方位、全过程育人体系没有完全建立。课程思政是有效发挥课堂育人主渠道作用的必然选择。基于医学教育的特有规律,我们以“健康中国2... 详细信息

高校立身之本在于立德树人。长期以来,高校教师注重了对学生的知识传授而忽视了价值引领,导致全员、全方位、全过程育人体系没有完全建立。课程思政是有效发挥课堂育人主渠道作用的必然选择。基于医学教育的特有规律,我们以“健康中国2030”和“卓越医生教育培养计划2.0”服务健康中国为指导,对临床医学专业生物化学课程的课程思政进行探索。通过加强教师“立德树人”的综合教育理念的培训、建设生物化学的思政元素资料库、挖掘课程蕴含的思政元素,密切关注国情社情,培养责任担当等,来自师生的反馈表明课程思政有机融入生物化学教学已取得良好效果。本文也对课程思政实施过程中存在的问题和挑战进行讨论。

关键词：课程思政生物化学医学生

刀锋伪影校正技术在精神疾病患者海马MRI检查中的应用

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波谱学杂志 2019年第3期36卷 261-267页

作者：邵丹丹王雪雪潘自来陈克敏张中帅袁莉莉许子悦陈磊王金红上海交通大学医学院附属瑞金医院北院放射科上海200025 上海交通大学医学院附属精神卫生中心医学影像科上海200030 上海西门子医疗上海201318

为探讨磁共振刀锋伪影校正(BLADE)技术提升精神疾病患者海马磁共振图像质量的效果,本文分别使用结合了BLADE技术的BLADE T2WI TSE、BLADE T2WI FLAIR及传统T2WI TSE、T2WI FLAIR四种序列,对47例精神疾病患者和美国放射学院(ACR)标准模体... 详细信息

为探讨磁共振刀锋伪影校正(BLADE)技术提升精神疾病患者海马磁共振图像质量的效果,本文分别使用结合了BLADE技术的BLADE T2WI TSE、BLADE T2WI FLAIR及传统T2WI TSE、T2WI FLAIR四种序列,对47例精神疾病患者和美国放射学院(ACR)标准模体在3.0 T磁共振成像(MRI)设备上分别进行常规海马斜冠状位扫描和ACR标准检测.患者的磁共振图像由2名放射科医师采用5分法对运动伪影、搏动伪影、颗粒度、海马磁共振图像质量进行评价,并应用Wilcoxon符号秩检验进行数据分析.模体图像通过识别图像的钻孔阵列和轮辐的数目,半定量评价各序列的高对比空间分辨力(HCSR)和低对比物体探测能力(LCD).结果表明相比传统序列,结合BLADE技术的序列能够明显改善海马磁共振图像的运动伪影、搏动伪影(p<0.001),提高图像质量(p<0.05);但在图像颗粒度方面,传统序列表现更优(p<0.001).ACR模体半定量分析显示,结合BLADE技术序列与传统序列相比,在LCD检测方面结果更优、在HCSR检测方面结果相同或略逊.本文推荐将BLADE技术应用于不合作的精神疾病患者海马的MRI检查.

关键词：刀锋伪影校正(BLADE) 磁共振图像精神疾病海马