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AstroPose:astronaut pose estimation using a monocular camera during extravehicular activities

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Science china(Technological Sciences) 2024年第6期67卷 1933-1945页

作者： LIU ZiBin LI You WANG ChunHui LIU Liang GUAN BangLei SHANG Yang YU QiFeng College of Aerospace Science and Engineering National University of Defense TechnologyChangsha410073China Key Laboratory of Human Factors Engineering China Astronaut Research and Training CenterBeijing100094China

With the completion of the Chinese space station,an increasing number of extravehicular activities will be executed by astronauts,which is regarded as one of the most dangerous activities in human space *** guarantee the safety of astronauts and the successful accomplishment of missions,it is vital to determine the pose of astronauts during extravehicular *** article presents a monocular vision-based pose estimation method of astronauts during extravehicular activities,making full use of the available observation ***,the camera is calibrated using objects of known structures,such as the spacesuit backpack or the circular handrail outside the space ***,the pose estimation is performed utilizing the feature points on the *** proposed methods are validated both on synthetic and semi-physical simulation experiments,demonstrating the high precision of the camera calibration and pose *** further evaluate the performance of the methods in real-world scenarios,we utilize image sequences of Shenzhou-13 astronauts during extravehicular *** experiments validate that camera calibration and pose estimation can be accomplished solely with the existing observation resources,without requiring additional complicated *** motion parameters of astronauts lay the technological foundation for subsequent applications such as mechanical analysis,task planning,and ground training of astronauts.

关键词： monocular camera astronaut pose estimation camera calibration

Welding depth measurement for different mode lasers using optical coherence tomography

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Chinese Optics Letters 2024年第1期22卷 41-46页

作者：谢冠明王三宏张跃强李由胡彪傅愉于起峰 Institute of Intelligent Optical Measurement and Detection Shenzhen UniversityShenzhen 518060China College of Physics and Optoelectronic Engineering Shenzhen UniversityShenzhen 518060China Shenzhen Sincevision Technology Co. Ltd.Shenzhen 518055China National Key Laboratory of Human Factors Engineering China Astronaut Research and Training CenterBeijing 100094China College of Aerospace Science and Engineering National University of Defense TechnologyChangsha 410073China

Optical coherence tomography(OCT)allows a direct and precise measurement of laser welding depth by coaxially measuring the keyhole depth and can be used for process monitoring and *** OCT measurement was taken during single-beam laser welding,the keyhole instability of aluminum welding resulted in highly scattered OCT data and complicated the welding depth extraction *** a combination of an inner core beam and an outer ring beam,a novel adjustable ring mode(ARM)laser for producing a stable keyhole was applied to the OCT *** ARM laser power arrangements were conducted on aluminum and *** results indicated that the ring beam greatly improved the stability of the core beam-induced keyhole,and smooth welding depth can be extracted from the concentrated OCT data.

关键词： optical coherence tomography adjustable ring mode laser laser welding welding depth

Fast solution to the free return orbit's reachable domain of the manned lunar mission by deep neural network

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Journal of Systems Engineering and Electronics 2024年第2期35卷 495-508页

作者： YANG Luyi LI Haiyang ZHANG Jin ZHU Yuehe College of Aerospace Science and Engineering National University of Defense TechnologyChangsha 410073China china astronauts research and training center Beijing 100094China Hunan Key Laboratory of Intelligent Planning and Simulation for Aerospace Missions Changsha 410073China

It is important to calculate the reachable domain(RD)of the manned lunar mission to evaluate whether a lunar landing site could be reached by the spacecraft. In this paper, the RD of free return orbits is quickly evaluated and calculated via the classification and regression neural networks. An efficient databasegeneration method is developed for obtaining eight types of free return orbits and then the RD is defined by the orbit’s inclination and right ascension of ascending node(RAAN) at the perilune. A classify neural network and a regression network are trained respectively. The former is built for classifying the type of the RD, and the latter is built for calculating the inclination and RAAN of the RD. The simulation results show that two neural networks are well trained. The classification model has an accuracy of more than 99% and the mean square error of the regression model is less than 0.01°on the test set. Moreover, a serial strategy is proposed to combine the two surrogate models and a recognition tool is built to evaluate whether a lunar site could be reached. The proposed deep learning method shows the superiority in computation efficiency compared with the traditional double two-body model.

关键词： manned lunar mission free return orbit reachable domain(RD) deep neural network computation efficiency

Thiamine-modified metabolic reprogramming of human pluripotent stem cell-derived cardiomyocyte under space microgravity

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Signal Transduction and Targeted Therapy 2024年第5期9卷 2132-2142页

作者： Xinglong Han Lina Qu Miao Yu Lingqun Ye Liujia Shi Guangfu Ye Jingsi Yang Yaning Wang Hao Fan Yong Wang Yingjun Tan Chunyan Wang Qi Li Wei Lei Jianghai Chen Zhaoxia Liu Zhenya Shen Yinghui Li Shijun Hu Department of Cardiovascular Surgery of the First Affiliated Hospital&Institute for Cardiovascular Science State Key Laboratory of Radiation Medicine and ProtectionSuzhou Medical CollegeSoochow UniversitySuzhouChina State Key Laboratory of Space Medicine China Astronaut Research and Training CenterBeijingChina Department of Hand Surgery Union HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhanChina

During spaceflight,the cardiovascular system undergoes remarkable adaptation to microgravity and faces the risk of cardiac ***,the effects and mechanisms of microgravity on cardiac morphology,physiology,metabolism,and cellular biology need to be further *** china started constructing the china Space Station(CSS)in 2021,we have taken advantage of the Shenzhou-13 capsule to send human pluripotent stem cell-derived cardiomyocytes(hPSC-CMs)to the Tianhe core module of the *** this study,hPSC-CMs subjected to space microgravity showed decreased beating rate and abnormal intracellular calcium *** and transcriptomic analyses revealed a battery of metabolic remodeling of hPSC-CMs in spaceflight,especially thiamine *** microgravity condition blocked the thiamine intake in *** decline of thiamine utilization under microgravity or by its antagonistic analog amprolium affected the process of the tricarboxylic acid *** decreased ATP production,which led to cytoskeletal remodeling and calcium homeostasis imbalance in *** importantly,in vitro and in vivo studies suggest that thiamine supplementation could reverse the adaptive changes induced by simulated *** study represents the first astrobiological study on the china Space Station and lays a solid foundation for further aerospace biomedical *** data indicate that intervention of thiamine-modified metabolic reprogramming in human cardiomyocytes during spaceflight might be a feasible countermeasure against microgravity.

关键词： programming battery modified

Trends and Age-Period-Cohort Effect on Incidence of Varicella Under Age 35—china,2005-2021

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china CDC weekly 2024年第18期6卷 390-395,I0005页

作者： Guijie Luan Hongyan Yao Dapeng Yin Jianjun Liu Department of Education and training Chinese center for Disease Control and PreventionBeijingChina Hainan Provincial center for Disease Control and Prevention Haikou CityHainan ProvinceChina Chinese center for Disease Control and Prevention BeijingChina

Summary What is already known about this topic?Varicella is an acute respiratory infectious disease primarily affecting ***,recent studies have indicated an increasing susceptibility to varicella among older age *** is added by this report?The findings demonstrate a significant rise in the incidence rate among individuals aged *** under 20 years old were found to have a higher risk compared to females,whereas males had a lower risk compared to females aged 20-35 years.

关键词： acute respiratory Incidence

Resveratrol combats chronic diseases through enhancing mitochondrial quality

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Food Science and Human Wellness 2024年第2期13卷 597-610页

作者： Weichu Tao Hu Zhang Xia Jiang Ning Chen Tianjiu research and Development center for Exercise Nutrition and Foods Hubei Key Laboratory of Exercise Training and MonitoringCollege of Sports MedicineWuhan Sports UniversityWuhan 430079China The University Hospital of Wuhan Sports University Wuhan 430079China

Resveratrol(RSV),as a functional food component extracted from natural plants,has been widely studied and recognized in preventing and treating various diseases,with major mechanisms including executing anti-inflammation and anti-oxidation functions,and improving mitochondrial *** diseases as non-communicable diseases are mainly caused by multiple factors,such as physiological decline and dysfunction in the body,and have become a significant challenge on public health *** is worth noting that chronic diseases such as Alzheimer's disease(AD),Parkinson's disease(PD),muscle atrophy,cardiovascular disease,obesity,and cancer are accompanied by abnormal mitochondrial ***,targeted regulation of mitochondria may be a meaningful way to prevent and treat chronic *** evidence has confirmed that RSV is actively involved in regulating mitochondria,and it has become an essential consideration to prevent and treat chronic diseases through targeting mitochondria and improving corresponding *** this article,current studies on RSV to optimize mitochondrial quality for preventing and alleviating chronic disease are systematically summarized,which can provide a theoretical reference for the development of functional foods or drugs to combat chronic diseases.

关键词： Resveratrol Functional food Mitochondrial quality Chronic disease Anti-inflammation Anti-oxidation

Cognitive impairment in cerebral small vessel disease induced by hypertension

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Neural Regeneration research 2024年第7期19卷 1454-1462页

作者： Weipeng Wei Denglei Ma Lin Li Lan Zhang Department of Pharmacy Xuanwu Hospital of Capital Medical UniversityBeijingChina Beijing Geriatric Medical research center Beijing Engineering Research Center for Nervous System DrugsNational Center for Neurological DisordersNational Clinical Research Center for Geriatric DiseasesBeijingChina

Hypertension is a primary risk factor for the progression of cognitive impairment caused by cerebral small vessel disease,the most common cerebrovascular *** r,the causal relationship between hypertension and cerebral small vessel disease remains *** has substantial negative impacts on brain health and is recognized as a risk factor for cerebrovascular *** hypertension and lifestyle factors are associated with risks for stro ke and dementia,and cerebral small vessel disease can cause dementia and *** is the main driver of cerebral small vessel disease,which changes the structure and function of cerebral vessels via various mechanisms and leads to lacunar infarction,leukoaraiosis,white matter lesions,and intracerebral hemorrhage,ultimately res ulting in cognitive decline and demonstrating that the brain is the to rget organ of *** review updates our understanding of the pathogenesis of hypertensioninduced cerebral small vessel disease and the res ulting changes in brain structure and function and declines in cognitive *** also discuss drugs to treat cerebral small vessel disease and cognitive impairment.

关键词： blood-brain barrier cerebral small vessel disease cognitive impairment dementia endothelial dysfunction enlarged perivascular space hypertension lacunar infarction neuroinflammation treatment white matter high signal intensity

Influence of Irregular Coastlines on a Tornadic Mesovortex in the Pearl River Delta during the Monsoon Season. Part Ⅰ:Pre-storm Environment and Storm Evolution

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Advances in Atmospheric Sciences 2024年第9期41卷 1115-1131页

作者： Lanqiang BAI Dan YAO Zhiyong MENG Yu ZHANG Xianxiang HUANG Zhaoming LI Xiaoding YU Foshan Tornado research center and China Meteorological Administration Tornado Key LaboratoryGuangdong Meteorological Serviceand Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai)Guangdong 528000China Meteorological Observation Centre CMABeijing 100081China Department of Atmospheric and Oceanic Sciences and China Meteorological Administration Tornado Key LaboratorySchool of PhysicsPeking UniversityBeijing 100871China Guangzhou Meteorological Observatory CMAGuangdong 511430China Foshan Tornado research center and China Meteorological Administration Tornado Key LaboratoryCMAGuangdong 528000China china Meteorological Administration training center CMABeijing 528000China

The Pearl River Delta(PRD),a tornado hotspot,forms a distinct trumpet-shaped coastline that concaves toward the South china *** the summer monsoon season,low-level southwesterlies over the PRD’s sea surface tend to be turned toward the west coast,constituting a convergent wind field along with the landward-side southwesterlies,which influences regional convective *** two-part study explores the roles of this unique land–sea contrast of the trumpet-shaped coastline in the formation of a tornadic mesovortex within monsoonal flows in this *** I primarily presents observational analyses of pre-storm environments and storm *** rotating storm developed in a lowshear environment(not ideal for a supercell)under the interactions of three air masses under the influence of the land–sea contrast,monsoon,and storm cold *** intersection zone(or“triple point”)is typically characterized by local enhancements of ambient vertical vorticity and *** on a rapid-scan X-band phased-array radar,finger-like echoes were recognized shortly after the gust front intruded on the triple *** over the triple point,they rapidly wrapped up with a well-defined low-level *** is thus presumed that the triple point may have played roles in the mesovortex genesis,which will be demonstrated in Part II with multiple sensitivity numerical *** findings also suggest that when storms pass over the boundary intersection zone in the PRD,the expected possibility of a rotating storm occurring is relatively high,even in a low-shear *** knowledge of such environments provides additional guidance to assess the regional tornado risk.

关键词： tornado mesovortex surface boundary land–sea contrast monsoon

Privacy-Preserving Federated Mobility Prediction with Compound Data and Model Perturbation Mechanism

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china Communications 2024年第3期21卷 160-173页

作者： Long Qingyue Wang Huandong Chen Huiming Jin Depeng Zhu Lin Yu Li Li Yong Beijing National research center for Information Science and Technology(BNRist) Department of Electronic EngineeringTsinghua UniversityBeijing 100084China china Mobile research Beijing 100032China

Human mobility prediction is important for many ***,training an accurate mobility prediction model requires a large scale of human trajectories,where privacy issues become an important *** rising federated learning provides us with a promising solution to this problem,which enables mobile devices to collaboratively learn a shared prediction model while keeping all the training data on the device,decoupling the ability to do machine learning from the need to store the data in the ***,existing federated learningbased methods either do not provide privacy guarantees or have vulnerability in terms of privacy *** this paper,we combine the techniques of data perturbation and model perturbation mechanisms and propose a privacy-preserving mobility prediction algorithm,where we add noise to the transmitted model and the raw data collaboratively to protect user privacy and keep the mobility prediction *** experimental results show that our proposed method significantly outperforms the existing stateof-the-art mobility prediction method in terms of defensive performance against practical attacks while having comparable mobility prediction performance,demonstrating its effectiveness.

关键词： federated learning mobility prediction privacy