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71.
Costas B. Tsiamis   《Acta Astronautica》2008,62(10-11):617-622
The physiological and biochemical systems that regulate the level of each electrolyte in blood and other endogenous fluids, and the balance between the consumption and loss of fluid and electrolytes and the total fluid and electrolyte content of the body are significantly affected during hypokinesia (HK; diminished movement). Among the known effects of HK, the fluid and electrolyte deficiency has drawn a great interest due to the higher fluid and electrolyte deficiency with higher than lower fluid and electrolyte consumption. The impossibility of the body to use fluid and electrolytes, after the fluid and electrolyte deficiency has been established, has drawn the greatest interest. The fluid shifting to the thoracic region and the daily body rehydration are considered as the most effective methods to counteract fluid and electrolyte changes. To this end, the objective of this review was to report some of the findings in the fluid and electrolyte deficiency and fluid and electrolyte loss with fluid and electrolyte deficiency during prolonged HK.  相似文献   
72.
稳态加速度模拟试验设备:离心机设计(3)   总被引:1,自引:0,他引:1  
文章分3篇10章详细介绍了稳态加速度模拟试验设备--离心机的设计.上篇对稳态加速度环境及其效应、相关试验方法和国家标准作了阐述;中篇(上)系统介绍了国内外离心机发展的历史,提供了较为全面具体的离心机结构概况,并对它们逐一进行小结与点评;中篇(下)对离心机进行基本理论分析,研究总体设计和部件设计问题,提出离心机设计原则及其计算方法;下篇通过一个国家"七五"科技攻关项目的实践作为实例,提供读者作设计参考.在文章中,作者对多年来积累的技术资料和实践心得进行了系统的整理和归纳,梳理出一条在离心机研制中科学的设计思路和实用的工作程序.该文章对相关领域的研究人员和技术人员会有启发和帮助,同时对其他同类设备的设计也有触类旁通的作用.文章主要探讨的对象是中型,大型、特大型航空航天物体离心机,土工离心机和载人离心机.  相似文献   
73.
The purpose of this work was to develop technology for recycling NaCl containing in human liquid waste as intrasystem matter in a bioregenerative life support system (BLSS). The circulation of Na+ and Cl excreted in urine is achieved by inclusion of halophytes, i.e. plants that naturally inhabit salt-rich soils and accumulate NaCl in their organs. A model of Na+ and Cl recycling in a BLSS was designed, based on the NaCl turnover in the human–urine–nutrient solution–halophytic plant–human cycle. The study consisted of (i) selecting a halophyte suitable for inclusion in a BLSS, and (ii) determining growth conditions supporting maximal Na+ and Cl accumulation in the shoots of the halophyte growing in a nutrient solution simulating mineralized urine. For the selected halophytic plant, Salicornia europaea, growth rate under optimal conditions, biomass production and quantities of Na+ and Cl absorbed were determined. Characteristics of a plant production conveyor consisting of S.europaea at various ages, and allowing continuity of Na+ and Cl turnover, were estimated. It was shown that closure of the NaCl cycle in a BLSS can be attained if the daily ration of fresh Salicornia biomass for a BLSS inhabitant is approximately 360 g.  相似文献   
74.
《Space Policy》2014,30(3):143-145
The human exploration of space is pushing the boundaries of what is technically feasible. The space industry is preparing for the New Space era, the momentum for which will emanate from the commercial human spaceflight sector, and will be buttressed by international solar system exploration endeavours. With many distinctive technical challenges to be overcome, human spaceflight requires that numerous biological and physical systems be examined under exceptional circumstances for progress to be made. To effectively tackle such an undertaking significant intra- and international coordination and collaboration is required. Space life and biomedical science research and development (R & D) will support the Global Exploration Roadmap (GER) by enabling humans to ‘endure’ the extreme activity that is long duration human spaceflight. In so doing the field will discover solutions to some of our most difficult human health issues, and as a consequence benefit society as a whole. This space-specific R&D will drive a significant amount of terrestrial biomedical research and as a result the international community will not only gain benefits in the form of improved healthcare in space and on Earth, but also through the growth of its science base and industry.  相似文献   
75.
The pace of scientific exploration of our solar system provides ever-increasing insights into potentially habitable environments, and associated concerns for their contamination by Earth organisms. Biological and organic-chemical contamination has been extensively considered by the COSPAR Panel on Planetary Protection (PPP) and has resulted in the internationally recognized regulations to which spacefaring nations adhere, and which have been in place for 40 years. The only successful Mars lander missions with system-level “sterilization” were the Viking landers in the 1970s. Since then different cleanliness requirements have been applied to spacecraft based on their destination, mission type, and scientific objectives. The Planetary Protection Subcommittee of the NASA Advisory Council has noted that a strategic Research & Technology Development (R&TD) roadmap would be very beneficial to encourage the timely availability of effective tools and methodologies to implement planetary protection requirements. New research avenues in planetary protection for ambitious future exploration missions can best be served by developing an over-arching program that integrates capability-driven developments with mission-driven implementation efforts. This paper analyzes the current status concerning microbial reduction and cleaning methods, recontamination control and bio-barriers, operational analysis methods, and addresses concepts for human exploration. Crosscutting research and support activities are discussed and a rationale for a Strategic Planetary Protection R&TD Roadmap is outlined. Such a roadmap for planetary protection provides a forum for strategic planning and will help to enable the next phases of solar system exploration.  相似文献   
76.
本文运用人力资本的概念分析了航空工业人才培养的重要性,同时根据人才成长的规律,结合航空工业的特点,得出了相应的人才培养的途径和方法。  相似文献   
77.
The question is: should the United States and nations at large pursue a human spaceflight program (and if so, why)? I offer an unwavering positive answer to this question, and state the reasons for it while considering the broad challenges and benefits of (human) spaceflight. Space exploration is a human activity that is intrinsically forward-looking, and as such, has positive potential. Both national and international space programs can galvanize the population, inspire the youth, foster job-creation, and motivate the existing workforce. The nature of the enterprises involved—their scale, novelty, and complexity—requires a steady and continuous upward progression toward greater societal, scientific and technological development. That is, in order to overcome the challenges of human spaceflight, progress is required. More to the point, the survival of humanity depends on expanding beyond the confines of our planet. Human spaceflight, in short, presents us with an opportunity to significantly advance the nation and the global community.  相似文献   
78.
This article introduces the methods for testing and verifying the performance of a new type of oxygen supply apparatus as well as the performance of the Environment Control and Life Support System(ECLSS)in the airtight unmanned space capsule,with a simulated human load instead of animals or human in China's Manned Space Program.The simulated human load also supplies a dummy for the spaceship to instal the envirmental testing equipment,to wear spacesuit,and to match the weight in spaceship.  相似文献   
79.
The human exploration of multiple deep space destinations (e.g. Cis-Lunar, NEAs), in view of the final challenge of sending astronauts to Mars, represents a current and consistent study domain especially in terms of its possible scenarios and mission architectures assessments, as proved by the numerous on-going activities about this topic and moreover by the global exploration roadmap. After exploring and analysing different possible solutions to identify the most flexible path, a detailed characterisation of several Design Reference Missions (DRMs) represents a necessity in order to evaluate the feasibility and affordability of deep space exploration missions, specifically in terms of enabling technological capabilities.The study presented in this paper was aimed at defining an evolutionary scenario for deep space exploration in the next 30 years with the final goal of sending astronauts on the surface of Mars by the end of 2030 decade. Different destinations were considered as targets to build the human exploration scenario, with particular attention to Earth–Moon Lagrangian points, NEA and Moon. For all the destinations selected as part of the exploration scenario, the assessment and characterisation of the relative Design Reference Missions were performed. Specifically they were defined in terms of strategies, architectures and mission elements. All the analyses were based on a pure technical approach with the objective of evaluating the feasibility of a long term strategy for capabilities achievement and technological development to enable future space exploration.This paper describes the process that was followed within the study, focusing on the adopted methodology, and reports the major obtained results, in terms of scenario and mission analysis.  相似文献   
80.
Radar Maneuvering Targets Tracking(RMTT) in clutter is a quite challenging issue due to the errors in the models and the varying dynamics of the processes. Modern radar tracking system calls for the adaptive signal and data processing algorithm urgently to adapt the uncertainty of the environment. The mechanism of human cognition can help persons cope with the similar diffi-culties in visual tracking. Inspired by human cognition mechanism, a comprehensive method for RMTT is proposed. In the method, the model transition probability in Interacting Multiple Model(IMM) and the validation gate can be adjusted dynamically with target maneuver; the waveform in radar transmitter can vary with the perception of the environment. Experimental results in cluttered scenes show that the proposed algorithm is more accurate for perceiving the environment and targets, and the waveform selection algorithm is better than that with fixed waveform.  相似文献   
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