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A Space-Flight Ship Travelling by a Plasma Rocket Engine from the Earth Ground to the Moon
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作者 Mitsuaki Nagata 《Journal of Modern Physics》 2023年第12期1578-1586,共9页
Since a thrust of an ion rocket engine is much weaker than the one of a chemical fuel engine, nowadays, ion engines are used mainly in spaces where gravities are very weak. Here, as a powerful plasma rocket to make a ... Since a thrust of an ion rocket engine is much weaker than the one of a chemical fuel engine, nowadays, ion engines are used mainly in spaces where gravities are very weak. Here, as a powerful plasma rocket to make a heavy ship get out from the gravity-sphere of the earth without relying on an atomic power rocket, an ion-velocity booster is investigated. It is a main challenge how to protect the engine wall from the melting due to collisions of ions which grow into high-energy particles. 展开更多
关键词 Plasma Fuel Rocket space-flight Ship to the Moon Ion-Velocity Booster
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Study on Mutagenic Effect of Space Flight in Two-line Sterile Rice 被引量:1
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作者 杨震 彭选明 +2 位作者 彭伟正 庞爱军 庞伯良 《Agricultural Science & Technology》 CAS 2009年第4期105-107,174,共4页
Seeds of two-line sterile rice cultivars Zhu 1S and Lu 18S were carried into space by "Shijian 8" breeding recoverable satellite, then planted in ground. Mutagenic effects from space induction were compared with tho... Seeds of two-line sterile rice cultivars Zhu 1S and Lu 18S were carried into space by "Shijian 8" breeding recoverable satellite, then planted in ground. Mutagenic effects from space induction were compared with those from y-irradiation and complex processing of space induction and y-irradiation. The results showed that agronomic effect was stimulated in Mo progenies of the two-line sterile rice varieties treated by space flight, and their radiosensitivities to the irradiation of space flight performed non-sensitive. The order of mutation frequency was determined to be SP + γ 〉 γ 〉 SP in M2 generation. And a series of mutated elites(individuals) were screened. Physiological indices of mutants screened like the activity of protective enzymes were measured to explore the physiological and biochemical basis of biological effect in space environment to two-line sterile rice. The results of this study show that space mutation breeding is an effective novel mean for breeding. 展开更多
关键词 space flight y-irradiation Complex process Two-line sterile variety Mutagenic effects
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Aerodynamic map for soft and hard hypersonic level flight in near space 被引量:11
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作者 Ruifeng Hu Ziniu Wu Zhe Wu Xiaoxin Wang Zhongwei Tian School of Aerospace, Tsinghua University, 100084 Beijing, China 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2009年第4期571-575,共5页
In this note, we design a velocity-altitude map for hypersonic level flight in near space of altitude 20-100 km. This map displays aerodynamic-related parameters associated with near space level flight, schematically ... In this note, we design a velocity-altitude map for hypersonic level flight in near space of altitude 20-100 km. This map displays aerodynamic-related parameters associated with near space level flight, schematically or quantitatively. Various physical conditions for the near-space level flight are then characterized, including laminar or turbulent flow, rarefaction or continuous flow, aerodynamic heating, as well as conditions for sustaining level flight with and without orbital effect. This map allows one to identify conditions to have soft flight or hard flight, and this identification would be helpful for making correct planning on detailed studies of aerodynamics or making initial design of near space vehicles. 展开更多
关键词 Near space AERODYNAMICS HYPERSONIC Level flight Soft flow
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Acclimation during spaceflight:effects on human emotion 被引量:3
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作者 Qing Liu Ren-Lai Zhou +2 位作者 Xin Zhao Xiao-Ping Chen Shan-Guang Chen 《Journal of Medical Colleges of PLA(China)》 CAS 2016年第3期162-167,共6页
Recently,studies on the extent to which spaceflight affects the psychology of individuals has received attention.In order to reveal the mental challenges that humans face in space,we need practical viewpoints to integ... Recently,studies on the extent to which spaceflight affects the psychology of individuals has received attention.In order to reveal the mental challenges that humans face in space,we need practical viewpoints to integrate the psychological effects,behavior,performance and the environment itself for space exploration.The present review discusses the individual variables related to space psychology and manned spaceflight,in addition to their growing trends.These items include patterns of emotional changes in extreme environments and the approaches to evaluating emotions.Moreover,the review concludes with suggested future research on emotion during spaceflight and its analogs.These data and information are needed to plan for the exploration of the Moon and Mars,along with contributions to the construction of the international space station(ISS) and astronaut training. 展开更多
关键词 space flight WEIGHTLESSNESS EMOTION PHYSIOLOGY
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Are We Learning as Much as Possible from Spaceflight to Better Understand Health and Risks to Health on Earth, as Well as in Space? 被引量:3
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作者 David A. Hart 《Journal of Biomedical Science and Engineering》 2018年第6期109-118,共10页
The objective of this review is to discuss the changes in human biology and physiology that occur when humans, who evolved on Earth for millions of years, now are subjected to space flight for extended periods of time... The objective of this review is to discuss the changes in human biology and physiology that occur when humans, who evolved on Earth for millions of years, now are subjected to space flight for extended periods of time, and how detailing such changes associated with space flight could help better understand risks for loss of health on Earth. Space programs invest heavily in the selection and training of astronauts. They also are investing in maintaining the health of astronauts, both for extensive stays in low earth orbit on ISS, and in preparation for deep space missions in the future. This effort is critical for the success of such missions as the N is small and the tasks needed to be performed in a hostile environment are complex and demanding. However, space is a unique environment, devoid of many of the “boundary conditions” that shaped human evolution (e.g. 1 g environment, magnetic fields, background radiation, oxygen, water, etc). Therefore, for humans to be successful in space, we need to learn to adapt and minimize the impact of an altered environment on human health. Conversely, we can also learn considerably from this altered environment for life on earth. The question is, are we getting the maximal information from life in space to learn about like on earth? The answer is likely No, and as such, our “Return on Investment” is not as great as it could be. Even though the number of astronauts is not large, what we can learn from them could help shape new questions for research focused on health for those on earth, as well is contribute to “precision health” from the study of astronaut diversity. This latter effort would contribute to both the health of astronauts identifying risks, as well as contribute to health on earth via better understanding of the human genome and epigenome, as well as factors contributing to risk for diseases on earth, particularly as individuals age and regulatory systems become altered. Better use of the International Space Station, and similar platforms in the future, could provide critical insights in aging-associated risks for loss of health on Earth, as well as promote new approaches to using precision medicine to overcome threats to health while in space. To achieve this goal will likely require advanced approaches to collecting such information and use of more systems biology, systems physiology approaches to integrate the information. 展开更多
关键词 Physiology Genome EPIGENOME space flight PRECISION Medicine PRECISION HEALTH Silent Mutations Accelerated Aging
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Thermal comfort and thermoregulation in manned space flight 被引量:2
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作者 Zhen-zhong YANG Jin-xue FEI Xue-jun YU 《中国应用生理学杂志》 CAS CSCD 2013年第6期518-524,共7页
Exposure to thermal environment is one of the main concerns for manned space exploration. By focusing on the works performed on thermoregulation at microgravity or simulated microgravity, we endeavored to review the i... Exposure to thermal environment is one of the main concerns for manned space exploration. By focusing on the works performed on thermoregulation at microgravity or simulated microgravity, we endeavored to review the investigation on space thermal environmental physiology. First of all, the application of medical requirements for the crew module design from normal thermal comfort to accidental thermal emergencies in a space craft will be addressed. Then, alterations in the autonomic and behavioral temperature regulation caused by the effect of weightlessness both in space flight and its simulation on the ground are also discussed. Furthermore, countermeasures like exercise training, simulated natural ventilation, encouraged drink, etc., in the protection of thermoregulation during space flight is presented. Finally, the challenge of space thermal environment physiology faced in the future is figured out. 展开更多
关键词 载人航天飞行 体温调节 热舒适性 模拟微重力 环境生理学 空间飞行 太空探索 应用程序
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SpaceX 公司星舰航天器载人深空探测任务浅析 被引量:1
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作者 赵毓 王平 +2 位作者 侯振东 彭超然 余欢 《宇航学报》 EI CAS CSCD 北大核心 2023年第5期I0010-I0015,共6页
针对星舰航天器载人深空探测任务,概述了系统基本情况,介绍了SpaceX公司针对该系统支持载人月球、载人火星探测任务的初步方案,分别对星舰航天器飞行期间和星表停留期间的能力及性能需求进行分析,考虑实际工程情况估算了任务规模并总结... 针对星舰航天器载人深空探测任务,概述了系统基本情况,介绍了SpaceX公司针对该系统支持载人月球、载人火星探测任务的初步方案,分别对星舰航天器飞行期间和星表停留期间的能力及性能需求进行分析,考虑实际工程情况估算了任务规模并总结了关键技术,最后针对载人深空探测提出了几点思考与建议,可为后续工程规划及方案论证提供参考。 展开更多
关键词 载人航天 航天器 载人月球探测 载人火星探测 星舰
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Physiological Response of Space Flight Mutation New Strains of Festuca arundinacea to High Temperature Stress and Comprehensive Evaluation
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作者 Li Juan Lei Xia +3 位作者 Zhong Li Wang Xiaoli Yang Chunyan Wu Jiahai 《Animal Husbandry and Feed Science》 CAS 2017年第5期326-333,共8页
[Objective] The paper was to understand the physiological response of space flight mutation new strains of Festuca arundinacea to high temperature stress. [Method] The influence of high temperature stress on eco-physi... [Objective] The paper was to understand the physiological response of space flight mutation new strains of Festuca arundinacea to high temperature stress. [Method] The influence of high temperature stress on eco-physiological characteristics of 11 F. arundinacea materials was studied in a pot experiment.Physiological and biochemical indexes,including soluble protein content,superoxide dismutase( SOD),peroxidase( POD) and catalase( CAT) activities,were measured and analyzed once every 4 d for a total of three times. Subordinate function and grey rational analysis were used to comprehensively evaluate the heat resistance of 11 materials. [Result] The soluble protein content decreased with the extension of heat resistance stress,while SOD,POD and CAT activities showed an upward trend. The high temperature resistance of 11 F. arundinacea materials was evaluated by subordinate function method. The resistance order was SP5-85> SP5-60 > SP5-71 > SP5-42 > SP5-94 > SP5-7 > SP5-88 > F. arundinacea cv Shuicheng > SP5-5 > SP5-89 = F. arundinacea cv Qiancao No. 1. The relational order of various heat resistance indexes and heat resistance obtained by grey rational analysis was SOD > CAT > POD > soluble protein content. [Conclusion]The result provides a theoretical basis for stress physiology and stress breeding of cold season grass in southwest region. 展开更多
关键词 FESTUCA arundinacea High temperature STRESS space flight MUTATION PHYSIOLOGICAL characteristics COMPREHENSIVE evaluation
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Effects of Space Flight on Expression of Key Proteins in Rice Leaves
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作者 Zeng Deyong Cui Jie +6 位作者 Yin Yishu Zhang Meng Shan Shan Gao Xin Zhang Yingchun Sun Yeqing Lu Weihong 《Rice science》 SCIE CSCD 2020年第5期423-433,I0026-I0033,共19页
As a unique form of abiotic stress, the environmental conditions of outer space are expected to induce changes in plant genomes, proteomes and metabolic pathways. However, the effect of outer space conditions on the o... As a unique form of abiotic stress, the environmental conditions of outer space are expected to induce changes in plant genomes, proteomes and metabolic pathways. However, the effect of outer space conditions on the overall physiology of plants at the protein level has yet to be reported. To investigate the effects of outer space conditions on the growth-and development-related physiological processes and metabolic pathways of rice different stages, the seeds of rice variety DN423 were sent into orbit for 12.5 d aboard the SJ-10 Returning Satellite, and then the seedlings of both treated and control rice were compared at the three-leaf stage(TLS) and tillering stage(TS). In addition to comparing plant growth and reactive oxygen species(ROS) levels, seedling proteomes were also compared using isobaric tags for relative and absolute quantitation(i TRAQ). Space flight increased TLS plant height by 20%, reduced and increased ROS levels of the TLS and TS seedlings, respectively, and affected the expression of 36 and 323 proteins in TLS and TS leaves, respectively. Furthermore, the functions of the differentially abundant proteins were mainly associated with metabolism, energy, and protein synthesis and degradation. These results suggested that the exposure of seeds to outer space conditions affects the subsequent abundance of key signaling proteins, gene expression, and the processes of protein synthesis and degradation, thereby affecting metabolic processes and promoting adaptation to the abiotic stress of outer space. As such, the present study sheds light on the effects of space flight on plants and contributes to a more comprehensive understanding of extraterrestrial biology. 展开更多
关键词 differentially abundant protein RICE PROTEOMICS space flight isobaric tags for relative and absolute quantitation
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Recent Development in the Space Utility System of China's Manned Space Flight Program
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作者 Gu Yidong Guo Jiong 《空间科学学报》 CAS CSCD 北大核心 2010年第5期388-391,共4页
This paper briefly introduces the history of China's Manned Space Flight Program and concludes the experiments done since 2008,namely,a small satellite and a material science experiment.An outlook of future Chines... This paper briefly introduces the history of China's Manned Space Flight Program and concludes the experiments done since 2008,namely,a small satellite and a material science experiment.An outlook of future Chinese Space Station is also described at the end. 展开更多
关键词 载人航天计划 空间站 飞行方案 中国 科学实验 小型卫星
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Space Flight, Astronautics and Light Barrier
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作者 SongJian 《工程科学(英文版)》 2005年第2期1-9,共9页
Amazing achievements and accomplishments of space science and technologies in the past half-century have profoundly affected all disciplines of natural science and engineering. By the end of 20(th) Century, man or man... Amazing achievements and accomplishments of space science and technologies in the past half-century have profoundly affected all disciplines of natural science and engineering. By the end of 20(th) Century, man or man-made spacecrafts landed, or approached and surveyed all planets of solar system and their moons except Pluto. Biologists believe that life may emerge and evolve wherever liquid water exists. No liquid water is ever found yet on all planets and their moons in Solar System except for our Earth. Our mother planet turned out to be the only life-supporting oasis within 4 light years of the Milky Way. It is suggested in this article that time has come for science and engineering communities to study and prepare interstellar flight of manned or unmanned spacecrafts beyond Solar System. Four issues are to be addressed as prerequisite for such flight, namely, detailed survey of nearby space beyond Solar System, design of nuclear fusion rocket engine, long-sustainable on-board life-supporting system and breakthrough of the light barrier. 展开更多
关键词 空间探测 航天学 光栅 星际飞行
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基于多维空间的航路利用率 被引量:1
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作者 谢春生 胡泽涛 张兆宁 《科学技术与工程》 北大核心 2024年第7期3004-3009,共6页
航路利用率表征了空域中航路的利用情况,通过计算航路利用率可以实现对空域资源进行更合理、高效的利用。为了更加准确地计算给定时间段内固定航路的利用率,通过构建抽象的三维空间,提出了一种基于多维空间的航路利用率计算方法。在考... 航路利用率表征了空域中航路的利用情况,通过计算航路利用率可以实现对空域资源进行更合理、高效的利用。为了更加准确地计算给定时间段内固定航路的利用率,通过构建抽象的三维空间,提出了一种基于多维空间的航路利用率计算方法。在考虑时间和空间两个角度之间的相互联系有了突破,从时间、航路、高度层三个维度建立航路时空利用率计算模型计算航路时空利用率,结合航路容量利用率,从时间、空间、容量三个角度出发,建立了航路利用率计算模型。最后通过算例分析计算得到某一空域四条航路的利用率。 展开更多
关键词 航路利用率 多维空间 高度层 航路 航路时空利用率 航路容量利用率
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亚轨道载人飞行发展研究
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作者 王硕 包文龙 +3 位作者 贾贺 刘康 王臻 高树义 《航天返回与遥感》 CSCD 北大核心 2024年第4期1-8,共8页
二十一世纪,商业航天是世界航天产业经济发展的重要引擎。亚轨道载人飞行作为载人航天的商业外延,体现出低成本、高可靠和便捷性好的特点,是商业航天追逐的热门赛道。文章对国际上亚轨道载人飞行的发展现状进行了调研,从可行性、用户需... 二十一世纪,商业航天是世界航天产业经济发展的重要引擎。亚轨道载人飞行作为载人航天的商业外延,体现出低成本、高可靠和便捷性好的特点,是商业航天追逐的热门赛道。文章对国际上亚轨道载人飞行的发展现状进行了调研,从可行性、用户需求和经济效益等方面,对三种亚轨道载人飞行形式进行了对比分析。结果表明,载人飞船方案是亚轨道载人飞行最合适的发展方向;载人飞船后续发展需重点突破可重复使用火箭技术、逃逸救生技术及无损回收技术。 展开更多
关键词 亚轨道载人飞行 高空气球 空天飞机 载人飞船 分析规划
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全球空间安全治理视域下临近空间飞行监管研究
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作者 张超汉 胡熳馨 《太平洋学报》 北大核心 2024年第1期1-16,共16页
临近空间作为全球一体化的重要连接点,是实现长期驻空侦察、全球精准打击的军事战略高点。受空天划界论争的影响,临近空间飞行的监管规则仍依附于国内立法,在国际层面尚未实现有效规制和协调。在临近空间法律地位不清、监管主体不明、... 临近空间作为全球一体化的重要连接点,是实现长期驻空侦察、全球精准打击的军事战略高点。受空天划界论争的影响,临近空间飞行的监管规则仍依附于国内立法,在国际层面尚未实现有效规制和协调。在临近空间法律地位不清、监管主体不明、监管客体不定、监管内容复杂、飞行活动存有争议的情况下,现有国际航空航天法律制度已无法满足调整此类新型利益关系的实践需要。构建针对性的监管制度不仅是行业有序发展的基础,也是确保地面国国防安全和临近空间资源有序开发利用的重要保障。在国内立法层面,中国可参鉴《临近空间管制公约(草案)》的相关条款,积极推进临近空间融入航空法或航天法的制度设计,或制定单行的临近空间法,以国内立法引领国际立法;在国际立法层面,应以国际民用航空组织为主导,通过修订《国际民用航空公约》(又称《芝加哥公约》)相关附件或增设临近空间飞行的新附件标准,推进国际统一规则的构建。 展开更多
关键词 临近空间飞行器 监管主体 监管客体 监管事项 国际统一规则 空间安全治理
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基于高度层与飞机类型的航路利用率研究
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作者 谢春生 胡泽涛 卢飞 《哈尔滨商业大学学报(自然科学版)》 CAS 2024年第3期370-377,共8页
航路利用率表征了空域中航路的利用情况.为了更加准确地计算航路的利用率,针对在航路上不同的高度层对不同类型的飞机具有不同的适用性问题,根据不同高度层和飞机类型的组合情况,从时间、空间、容量三个角度建立了一种基于高度层与飞机... 航路利用率表征了空域中航路的利用情况.为了更加准确地计算航路的利用率,针对在航路上不同的高度层对不同类型的飞机具有不同的适用性问题,根据不同高度层和飞机类型的组合情况,从时间、空间、容量三个角度建立了一种基于高度层与飞机类型的航路利用率计算模型.在考虑航路利用率的多维影响因素方面有了突破,通过算例分析计算得到某四条航路的利用率. 展开更多
关键词 航路利用率 高度层 飞机类型 航路时间利用率 航路空间利用率 航路容量利用率
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载银抗菌材料在载人航天水处理任务中的应用前景
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作者 褚厚娟 丁平 +3 位作者 胡清华 曹适意 熊涛 杨松林 《化工进展》 EI CAS CSCD 北大核心 2024年第9期5026-5034,共9页
银具有广谱抗菌、低毒无耐药性的特点,是一种可应用于长期载人航天任务水处理系统的优选抗菌剂。本文首先介绍了银的抗菌机理,分别从抗菌剂和载体材料两个角度对载银抗菌材料进行了分类,重点关注载银抗菌材料的缓释性能,并从银离子负载... 银具有广谱抗菌、低毒无耐药性的特点,是一种可应用于长期载人航天任务水处理系统的优选抗菌剂。本文首先介绍了银的抗菌机理,分别从抗菌剂和载体材料两个角度对载银抗菌材料进行了分类,重点关注载银抗菌材料的缓释性能,并从银离子负载优化、载体材料预处理和负载制备工艺优化三个角度总结了现阶段增强载银抗菌材料缓释性能的途径。结合地面水处理工程中载银抗菌材料的应用实际,现有载银抗菌材料的缓释效果有限,且银离子释放浓度低。基于长期载人航天任务中水处理系统杀菌抑菌的应用工况,要求载银抗菌材料能够实现长效稳定缓慢释放,基材性能稳定且无次生污染物溶出,并可耐受航天发射上行力学要求。如能实现,不仅是对现有空间站洁净水电解加银技术的补充,更对我国长期载人航天任务的多场景抑菌杀菌具有重要应用意义。 展开更多
关键词 载银抗菌材料 载人航天任务 水处理系统 长期抑菌
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载人月球探测混合云架构体系仿真系统研究
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作者 赵毓 王慎泉 +3 位作者 王平 黄震 周克亮 张琦 《宇航学报》 EI CAS CSCD 北大核心 2024年第1期21-34,共14页
针对载人月球探测工程任务需求,设计了一种基于混合云架构的体系仿真系统,实现了辅助设计、方案验证和协助任务等功能应用。分别从任务设计和应用模式角度分析了体系仿真系统功能需求;根据需求给出体系仿真系统总体架构,采用仿真平台和... 针对载人月球探测工程任务需求,设计了一种基于混合云架构的体系仿真系统,实现了辅助设计、方案验证和协助任务等功能应用。分别从任务设计和应用模式角度分析了体系仿真系统功能需求;根据需求给出体系仿真系统总体架构,采用仿真平台和仿真支持库统筹建设的方式,完成了系统开发与集成;提出了针对体系仿真系统建设涉及的体系建模、任务规划、推演展示、效能评估和系统联动与扩展关键技术实现方案;应用该系统实现了对典型载人月面活动场景的仿真,得到了关键参数模拟推演结果,验证了体系仿真系统各项功能有效性和正确性;最后给出了思考和展望。该体系仿真系统可支撑未来载人月球探测相关任务开展发展论证和综合评估验证,能够为同类系统开发提供方案参考。 展开更多
关键词 载人航天 月球探测任务 体系 仿真系统 混合云
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一种多飞行器协同的GNC系统飞行模拟平台设计
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作者 周远林 蔡彪 刘智勇 《空间控制技术与应用》 CSCD 北大核心 2024年第4期66-74,共9页
空间站在轨组装和长期运营阶段涉及到多飞行器独立飞行、飞行器间交会对接、多飞行器组合体融合控制、多飞行器分离过程控制和飞行器返回再入等复杂飞行任务,完整、真实的飞行模拟是必需且至关重要的.基于时间同步、实时数据交换的分布... 空间站在轨组装和长期运营阶段涉及到多飞行器独立飞行、飞行器间交会对接、多飞行器组合体融合控制、多飞行器分离过程控制和飞行器返回再入等复杂飞行任务,完整、真实的飞行模拟是必需且至关重要的.基于时间同步、实时数据交换的分布式一体化仿真架构,设计了一种多飞行器协同的通用半物理制导、导航与控制(guidance,navigation and control,GNC)系统飞行模拟平台,可很好地满足复杂系统的飞行模拟需要.平台由若干灵活、可扩展的通用模拟器构成,单个模拟器通过配置可以实现任一飞行器的功能,能够独立对指定飞行器的全任务过程进行仿真.平台通过靶场仪器组B时间码(inter-range instramentation group-B,IRIG-B)信号进行时间同步,利用1553B总线完成动力学仿真数据实时交换,并在多模拟器之间通过协调机制实现热并网后进行协同仿真.该模拟平台成功应用于空间站飞行控制演练. 展开更多
关键词 空间站 多飞行器协同 半物理 制导导航与控制 飞行模拟
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微重力对肝脏和结肠作用的研究进展
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作者 卢燕 郭明洲 +3 位作者 李惠凯 陈倩倩 邱孝丰 令狐恩强 《航天医学与医学工程》 CAS 2024年第4期268-272,共5页
随着我国航天技术的日益成熟与进步,航天员能够在空间站停留更长时间,完成更为复杂的空间实验和任务。在太空微重力环境下,失重不可避免地会对航天员的消化系统产生影响,尤其是肝脏和结肠,存在较多的生理和病理改变。微重力可对肝脏代... 随着我国航天技术的日益成熟与进步,航天员能够在空间站停留更长时间,完成更为复杂的空间实验和任务。在太空微重力环境下,失重不可避免地会对航天员的消化系统产生影响,尤其是肝脏和结肠,存在较多的生理和病理改变。微重力可对肝脏代谢功能、细胞增殖分化、氧化应激反应以及炎症因子水平产生影响。微重力可破坏结肠的肠道屏障、肠道菌群和微生态、肠道免疫以及肠—肝轴。然而,目前关于微重力对肝脏、结肠影响的研究尚未完全清楚,且对二者的病理改变缺乏可靠的诊断指标。因此,为探寻微重力对肝脏及结肠的损伤机制,保障宇航员消化系统健康,本文围绕微重力对肝脏、结肠影响的研究进展进行综述。 展开更多
关键词 微重力 失重 太空飞行 消化系统 肝脏 结肠
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基于平板电脑的距离自适应视功能自测方案的研究
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作者 王铭钦 陈子东 +3 位作者 张宇宁 沈小元 范燕媚 余敏斌 《航天医学与医学工程》 CAS 2024年第3期166-172,共7页
目的构建基于平板电脑的距离自适应视功能自测系统,并分析其精确性。方法基于配有摄像头的平板电脑,使用ArUco技术识别2 m范围内的二维码以进行实时测距,构建距离自适应的集视力(普通视标视力和不同对比度高通视标视力)、调节幅度和中心... 目的构建基于平板电脑的距离自适应视功能自测系统,并分析其精确性。方法基于配有摄像头的平板电脑,使用ArUco技术识别2 m范围内的二维码以进行实时测距,构建距离自适应的集视力(普通视标视力和不同对比度高通视标视力)、调节幅度和中心5°视野测定一体化的视觉功能检测系统。共纳入健康受试者22例(44眼)完成视功能检查,其中6名受试者在四种距离(1 m、1.25 m、1.6 m、2 m)分别完成视力测试,并在足矫和–3.00D欠矫模拟调节不足状态下分别完成调节幅度测试。比较程序读数距离和空间中二维码距平板屏幕实际距离;比较在不同距离的同种视标的视力测试结果一致性;分析足矫及欠矫状态下调节幅度的变化,并使用ICC法评估其可重复性;分析视野测试结果的对比敏感度阈值及有效性。结果实际距离与程序读数距离具有良好的一致性水平。相同对比度高通视标视力测试在不同距离的测试结果无显著差异(P>0.05),100%普通视标视力在0.9~1.1m距离范围内与其他距离结果存在显著差异(P<0.001)。测量3次调节幅度的ICC值为0.861(P<0.001);欠矫状态下的调节幅度较足矫状态更低,变化具有统计学差异(P<0.05)。双眼视野对比度阈值的上边缘值均值为16.92%,程序能正确识别视野缺损。结论本研究构建了一种基于平板电脑的距离自适应视功能自测系统,可在2 m内实时精准测距,根据距离自动调节初始视标的大小以精确呈现视标,进行视力、调节幅度及中心5°视野检测。该系统不受固定距离限制并且具有更高的检验效能,可应用于空间狭小且不能固定距离的空间站的视功能检测。 展开更多
关键词 航天相关神经眼综合征 视功能检测 距离自适应 高通视标
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