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901.
A simulation for flight of international crew on space station took place in Moscow from July 1999 to April 2000 (SFINCS) at the State Biomedical Institute of Russia (IBMP) isolation chambers. Objectives of this study were to identify concepts of psychosocial adaptation and of social interactions to develop an explanation of the transcultural group performance. Method: constructivist epistemology with grounded theory research and fourth generation evaluation were used. Data on processes and interactions were gathered during 110 days of confinement as a subject and extended to 240 days as an outside scientist. Results indicate that coping is influenced by usual coping strategies and coping behaviors inside. Several stresses and human factor issues were identified altering well being and performance inside the chambers. Enabling and limiting forces are discussed. A theory on transcultural group performance is proposed. Issues are raised that appear critical to selection, training and group performance.  相似文献   
902.
Today's space operations involve co-working of people with different ethnical, professional and organisational backgrounds. The aim of this study was to examine the implications of cultural diversity for efficient collaboration within the European Space Agency (ESA), and between ESA employees and representatives from other agencies. ESA employees from European countries (N=576) answered to the CULT Ground Survey. The results showed that differences in relation to leadership and decision making were the most important issues thought to interfere with efficient co-working within ESA, and between ESA employees and colleagues from other agencies. Employees who collaborated with more than three nationalities within ESA indicated most challenges in co-working due to differences in compliance, behavioural norms and competitiveness. Challenges in co-working differed between agencies, and these differences were consistent with value differences in the national populations. The results may have applied value for training of European employees working in international space program teams.  相似文献   
903.
Chad Anderson 《Space Policy》2013,29(4):266-271
On May 24, 2012 SpaceX's Dragon capsule was launched and in doing so became the first commercially built vehicle to berth with and carry cargo to the International Space Station (ISS). It successfully completed its mission and returned to the Pacific Ocean on May 31, 2012.1 The docking of Dragon represented a historic moment where a commercial enterprise managed to achieve that which had previously only been accomplished by governments. “In the history of spaceflight – only four entities have launched a space capsule into orbit and successfully brought it back to Earth: the United States, Russia, China, and SpaceX”.2 While this is a monumental accomplishment for private industry, we cannot ignore the value of public–private partnerships and the role that government played in enabling this incredible achievement.In this paper I will examine how public–private partnerships are enabling the development of the commercial space industry, viewed through the lens of the Rethinking Business Institutional Hybrid Framework put forward by University of Oxford professors Marc Ventresca and Alex Nichols in their Rethinking Business MBA course. I intend to demonstrate that the NASA versus Commercial Space argument is a false dichotomy and that only by working together can both sectors continue to push the boundaries of space travel and exploration. I plan to do this by first discussing how the NASA-SpaceX partnership came about and the reasoning behind it. I will then explore what a public–private partnership (PPP) is, as compared to other government privatization schemes, and explain why Space Act Agreements are significantly different from anything done previously. I will then analyze the impact of these agreements and outline their benefits in order to demonstrate the value they create, especially in areas of mutual value creation and economic development.  相似文献   
904.
航天材料空间环境效应损伤机制及关联性研究   总被引:1,自引:0,他引:1  
基于航天材料在轨将遭遇多种空间环境的作用且不同空间环境对航天材料的损伤存在一定的关联性,本文首先对航天材料的空间环境及效应进行了介绍,接着对真空、温度、微重力、等离子体、粒子辐射、太阳电磁辐射、空间大气、空间碎片及微流星体、空间污染、空间动力学、腐蚀及空间生物等环境对航天材料的损伤机制及不同损伤机制之间的关联性进行了研究,最后对需要进一步研究和关注的方向进行了讨论并给出了发展建议。  相似文献   
905.
《中国航空学报》2016,(3):688-703
An adaptive sliding mode control(ASMC) law is proposed in decentralized scheme for trajectory tracking control of a new concept space robot.Each joint of the system is a free ball joint capable of rotating with three degrees of freedom(DOF).A cluster of control moment gyroscopes(CMGs) is mounted on each link and the base to actuate the system.The modified Rodrigues parameters(MRPs) are employed to describe the angular displacements,and the equations of motion are derived using Kane's equations.The controller for each link or the base is designed separately in decentralized scheme.The unknown disturbances,inertia parameter uncertainties and nonlinear uncertainties are classified as a ‘‘lumped" matched uncertainty with unknown upper bound,and a continuous sliding mode control(SMC) law is proposed,in which the control gain is tuned by the improved adaptation laws for the upper bound on norm of the uncertainty.A general amplification function is designed and incorporated in the adaptation laws to reduce the control error without conspicuously increasing the magnitude of the control input.Uniformly ultimate boundedness of the closed loop system is proved by Lyapunov's method.Simulation results based on a three-link system verify the effectiveness of the proposed controller.  相似文献   
906.
根据已有的研究工作,对成像镜调焦机构系统做了进一步改进,并对模型进行了环境影响分析和考虑接触时的受力分析.文中详细给出了设计的基本原理及设计方法,该机构通过电机驱动丝杠完成对成像镜的移动.由接触分析结果可以看出,考虑接触约束时所计算得到的结果比较符合实际情况,结构的强度满足要求.  相似文献   
907.
Radiation exposure estimates for crew members on the surface of Mars may vary widely because of the large variations in terrain altitude. The maximum altitude difference between the highest (top of Olympus Mons) and the lowest (bottom of the Hellas impact basin) points on Mars is about 32 km. In this work estimates of radiation exposures as a function of altitude, from the Hellas impact basin to Olympus Mons, are made for a solar particle event proton radiation environment comparable to the Carrington event of 1859. We assume that the proton energy distribution for this Carrington-type event is similar to that of the Band Function fit of the February 1956 event. In this work we use the HZETRN 2010 radiation transport code, originally developed at NASA Langley Research Center, and the Computerized Anatomical Male and Female human geometry models to estimate exposures for aluminum shield areal densities similar to those provided by a spacesuit, surface lander, and permanent habitat as a function of altitude in the Mars atmosphere. Comparisons of the predicted organ exposures with current NASA Permissible Exposure Limits (PELs) are made.  相似文献   
908.
文章介绍了航天电子产品整机装联布线的原则、注意要点、方法、顺序及常见问题的处理。  相似文献   
909.
简明讨论了在大面积柔性高聚合物基底材料上制备空间应用薄膜的特点与要求,并对研制的大面积自动连续镀膜设备的结构与性能作了简介;比较深入地探讨了大面积柔性基底材料连续镀膜中对磁控靶和等离子体辉光放电场的要求与作用;介绍了柔性导电型第二表面镜的研制技术、性能与评价方法及结果。  相似文献   
910.
The DGW-I is a new material processing facility developed in China, which was firstly carried into orbit in November 1999 by the SZ-1 spacecraft and then in January 2001 carried by SZ-2 into space again, and successfully processed 6 samples of materials, including 3 samples of alloys, 2 of semiconductors and 1 sample of oxide crystal.  相似文献   
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