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1.
Recognizing the importance and fertility of the extra vehicular activity technologies in future space development and utilization, some related research activities have been conducted in Japan, though it has not committed itself to developing its own manned space flight capability. The purpose of this paper is to introduce and evaluate these EVA-related activities and to indicate the next step for Japan to get into the era of manned space activities including EVA in reality.  相似文献   

2.
Basing his comments around a report on the Space Power Systems 1997 conference, ‘Energy and Space for Humanity’, held in Montreal, 24-28 August 1997, Richard Boudreault describes the progress made in getting the concept of power from space accepted by the terrestrial utilities. Increasing worries about the sustainability of current power sources together with deregulation of power distribution make space power more attractive. However, the high cost of access to space is a barrier, though this is starting to fall.  相似文献   

3.
Europe is present in robotic exploration though the European Space Agency?s mandatory space science program and the optional Aurora program. In addition some member states are also involved in projects of non-European space faring countries through bilateral co-operations. Europe is also present in human exploration through the ISS utilization program. ESA and some of its member states participate in the activities of the International Space Exploration Coordination Group (ISECG), a club of 14 space agencies working for the elaboration of a global exploration roadmap. Finally, ESA and the European Union have initiated a political approach with the setting up of an international forum so as to elaborate a commonly agreed vision on space exploration at political level.  相似文献   

4.
With the beginning of space era, a new branch of medicine has arisen and has been developing along with human exploration of outer space. And even though space medicine mainly faces the same problems as traditional medicine--cosmonauts health care and their high efficiency--this branch, has its own features, associated with the unusual factors of space flight, of which weightlessness is the major one. During the development of manned cosmonautics (duration of a human stay in space has reached already 438 days), methods of cosmonauts medical support and monitoring of their condition have been developed, knowledge of human possibilities and methods of process of organism adaptation to various and frequently severe conditions of external environment have increased. All this led to the fact that nowadays space medicine can become useful for improvement of human health care not only in space but also on the Earth. Moreover, the problem of implementation of cosmonautics achievements, and in particular of space medicine, in practice of public health care presents one of the most important issues concerning human health care. It is also connected with public opinion which is more and more concerned about the efficiency of significant expenses on space activities, especially lately. People often are set by the questions: what has space given, what fruits has space research provided to mankind, which results of this research can be used on the Earth already today for improvement of their life, for discussion of many difficult earthly problems? In terms of using cosmonautics possibilities, its achievements for health care and treatment, it is possible to define a few branches, in which purposeful studies are carried out.  相似文献   

5.
Space is now a global business, yet the cost of getting to space is still high. Developing new launch vehicles that are cheaper, safer, and more reliable is the key to both rapid commercial growth and to more and better government uses of space. However, the R&D process leading to new launch vehicles is expensive and technically challenging; the past 50 years have seen many government development programs, but no major technological breakthroughs. Perhaps, it is therefore time to think about other ways of developing new launch vehicles. The best expertise in this field resides primarily with private companies and is spread across many actors and nations. A consortium led by space firms might be a better approach to opening up space in the 21st century. Governments will have to develop new policies treating space as though it were a commercial industry, in particular, relaxing export trade restrictions wherever possible. Issues of dual-use may be outweighed by the rapidly growing widespread availability of launch capabilities. Since new launch vehicles will require large up-front R&D expenditures, government support will continue to be needed to supplement private capital funds. Contributions to this effort should be international. However, difficult it might be in today's security conscious environment to reorient government policy, doing so may offer the most efficient and successful way to break the technological and economic barriers to more reliable access to space.  相似文献   

6.
UNCOPUOS recently celebrated its 50th anniversary and has a range of achievements to show for it. But it is now very different – in both type and number of members – from the organization established at the start of the Cold War and needs to consider its future direction. An obvious topic to pursue is the long-term sustainability (LTS) of space activities, which, after some false starts, has now been adopted. One Working, and Four Expert, Groups have been set up to examine different aspects of the subject, though care must be taken to ensure that these are properly integrated into a multidisciplinary framework. Despite valid objections that LTS could be used to deny access to space to latecomers to the club, it is important to proceed with LTS while taking account of delegations' concerns.  相似文献   

7.
Nicolas Peter   《Space Policy》2007,23(2):97-107
Science and technology (S&T) have always been at the heart of the European political construction. This started in the Cold War through a series of pan-European collaborative schemes in a panoply of different scientific fields like molecular biology and nuclear research. However, while most of these early collaborative patterns focused on intra-European cooperation, in the post-Cold War era international S&T relations have evolved to encompass a broader international dimension. The European Union is now building a diverse and robust network of cooperation with non-EU partners to become a centre of gravity in international S&T affairs. This increasing linkage between S&T and foreign policy is particularly explicit in space activities. Even though it is the newest space actor in Europe, the EU is pushing the continent to extend the scope of its partnerships with Russia and China, while at the same time modifying its relations with the traditional European partner, the USA, illustrating therefore the emergence of a distinct “EU space diplomacy”.  相似文献   

8.
《Acta Astronautica》2013,82(2):484-498
Many governmental space activities need to be planned with a time horizon that extends beyond the comfort zone of reliable technology development assessments and predictions. In an environment of accelerating technological change, a methodological approach to addressing non-core technology trends and potentially disruptive, game-changing developments not yet linked to the space sector is increasingly important to complement efforts in core technology R&D planning.Various models and organisational setups aimed at fulfilling this purpose are in existence. These include, with varying levels of relevance to space, the National Aeronautics and Space Administration (NASA) Institute for Advanced Concepts (NIAC, operational form 1998 to 2007 and recently re-established), the Defence Advanced Research Projects Agency of the US Department of Defence, the Massachusetts Institute of Technology (MIT) Medialab, the early versions of Starlab, the Lockheed Skunk Works and the European Space Agency's Advanced Concepts Team.Some of these organisations have been reviewed and assessed individually, though systematic comparison of their methods, approaches and results have not been published. This may be due in part to the relatively sparse scientific literature on organisational parameters for enabling disruptive innovation as well as to the lack of commonly agreed indicators for the evaluation of their performance. Furthermore, innovation support systems in the space sector are organised differently than in traditional, open competitive markets, which serve as the basis for most scholarly literature on the organisation of innovation. The present paper is intended to advance and stimulate discussion on the organisation of disruptive innovation mechanisms specifically for the space sector. It uses the examples of the NASA Institute for Advanced Concepts and the ESA Advanced Concepts Team, analyses their respective approaches and compares their results, leading to the proposal of measures for the analysis and eventual evaluation of research for disruptive innovation in the space sector.  相似文献   

9.
A. McLean  A. Swankie 《Space Policy》1998,14(2):107-114
Helios is the only example of a multilateral collaborative military space effort currently being pursued within Europe. As such, a unique tripartite project, the first generation of the programme has had significant successes, even though the project has been faced with severe spending constraints and hindered by political obstacles. Helios 2, on the other hand, is not faring quite as well. Plagued by problems, the project has been in effect grounded indefinitely by German reluctance and inability to finance their share of the proposed three satellites. This paper assesses the origins and development of the Helios programme, and the difficulties facing the second generation of this satellite system.  相似文献   

10.
Even though there are methods for the nonlinear propagation of the covariance the propagation of the covariance in current operational programs is based on the state transition matrix of the 1st variational equations, thus it is a linear propagation. If the measurement errors are zero mean Gaussian, the orbit errors, statistically represented by the covariance, are Gaussian. When the orbit errors become too large they are no longer Gaussian and not represented by the covariance. One use of the covariance is the association of uncorrelated tracks (UCTs). A UCT is an object tracked by a space surveillance system that does not correlate to another object in the space object data base. For an object to be entered into the data base three or more tracks must be correlated. Associating UCTs is a major challenge for a space surveillance system since every object entered into the space object catalog begins as a UCT. It has been proved that if the orbit errors are Gaussian, the error ellipsoid represented by the covariance is the optimum association volume. When the time between tracks becomes large, hours or even days, the orbit errors can become large and are no longer Gaussian, and this has a negative effect on the association of UCTs. This paper further investigates the nonlinear effects on the accuracy of the covariance for use in correlation. The use of the best coordinate system and the unscented Kalman Filter (UKF) for providing a more accurate covariance are investigated along with assessing how these approaches would result in the ability to correlate tracks that are further separated in time.  相似文献   

11.
Real-time studies on microalgae under microgravity   总被引:2,自引:0,他引:2  
Using remote sensing technique, we investigated real-time Nostoc sphaeroides Kütz (Cyanobacterium) in Closed System under microgravity by SHENZHOU-2 spacecraft in January 2001. The experiments had 1 g centrifuges in space for control and ground control group experiments were also carried out in the same equipments and under the same controlled condition. The data about the population growth of Nostoc sp. of experiments and temperature changes of system were got from spacecraft every minute. From the data, we can find that population growth of Nostoc sp. in microgravity group was higher than that of other groups in space or on ground, even though both the control 1 g group in space and 1 g group on ground indicated same increasing characteristics in experiments. The growth rate of 1.4 g group (centrifuged group on ground) was also promoted during experiment. The temperature changes of systems are also affected by gravity and light. Some aspects about those differences were discussed. From the discussion of these results during experiment, it can be found that gravity is the major factor to lead to these changes.  相似文献   

12.
Effect of weightlessness on sympathetic-adrenomedullary activity of rats.   总被引:1,自引:0,他引:1  
Three cosmic experiments were performed in which rats spent 18-20 days in space on board the biosatellites "COSMOS 782", "COSMOS 936" and "COSMOS 1129". The following indicators of the sympathetic-adrenomedullary system (SAS) activity were measured: tissue and plasma catecholamines (CA), CA-synthesizing enzymes--tyrosine hydroxylase (TH), dopamine-beta-hydroxylase (DBH), phenylethanolamine-N-methyltransferase (PNMT)--as well as CA-degrading enzymes-monoamine oxidase (MAO) and catechol-O-methyltransferase (COMT). Adrenal epinephrine (EPI) and norepinephrine (NE) as well as CA-synthesizing and degrading enzymes were not significantly changed in the animals after flight on COSMOS 782. On the other hand, a significant increase was found in heart CA, the indicator which is usually decreased after stress. 26 days after landing all values were at control levels. The results obtained, compared to our previous stress experiments on Earth, suggest that prolonged weightlessness does not appear to be a pronounced stressful stimulus for the SAS. Heart and plasma CA, mainly NE, were increased both in the group living in the state of weightlessness and the group living in a centrifuge and exposed to artificial gravitation 1 g (COSMOS 936), suggesting again that prolonged weightlessness is not an intensive stressful stimulus for the SAS. The animals exposed after space flight on COSMOS 1129 to repeated immobilization stress on Earth showed a significant decrease of adrenal EPI and an expressive increase of adrenal TH activity compared to stressed animals which were not in space. Thus, the results corroborate that prolonged state of weightlessness during space flight though not representing by itself an intensive stressful stimulus for the sympathetic-adrenomedullary system, was found to potentiate the response of "cosmic rats" to stress exposure after return to Earth.  相似文献   

13.
王海波  徐敏强  王日新  李玉庆 《宇航学报》2012,33(11):1636-1645
研究了一类约束条件复杂、具有多时间窗口特性的天地测控资源联合调度问题。建立了涵盖多种约束的问题数学模型和基于测控弧段时间序的无圈有向图模型,提出了一种蚁群优化-模拟退火算法(ACO\|SA)求解问题。探讨了两种算法的融合策略,完成了包括状态转移规则、可行解生成策略、信息素更新准则、邻域结构、快速退火计划等关键技术的设计实现。多个算例仿真和结果分析表明,测控弧段时间序能保证ACO\|SA得到高质量的优化结果,模拟退火机制能有效提高蚁群优化算法的收敛速度和求解质量,相比于基本遗传算法和先到先服务算法,ACO\|SA能得到质量更好的解。  相似文献   

14.
Lichens survive in space: results from the 2005 LICHENS experiment   总被引:5,自引:0,他引:5  
This experiment was aimed at establishing, for the first time, the survival capability of lichens exposed to space conditions. In particular, the damaging effect of various wavelengths of extraterrestrial solar UV radiation was studied. The lichens used were the bipolar species Rhizocarpon geographicum and Xanthoria elegans, which were collected above 2000 m in the mountains of central Spain and as endolithic communities inhabiting granites in the Antarctic Dry Valleys. Lichens were exposed to space in the BIOPAN-5 facility of the European Space Agency; BIOPAN-5 is located on the outer shell of the Earth-orbiting FOTON-M2 Russian satellite. The lichen samples were launched from Baikonur by a Soyuz rocket on May 31, 2005, and were returned to Earth after 16 days in space, at which time they were tested for survival. Chlorophyll fluorescence was used for the measurement of photosynthetic parameters. Scanning electron microscopy in back-scattered mode, low temperature scanning electron microscopy, and transmission electron microscopy were used to study the organization and composition of both symbionts. Confocal laser scanning microscopy, in combination with the use of specific fluorescent probes, allowed for the assessment of the physiological state of the cells. All exposed lichens, regardless of the optical filters used, showed nearly the same photosynthetic activity after the flight as measured before the flight. Likewise, the multimicroscopy approach revealed no detectable ultrastructural changes in most of the algal and fungal cells of the lichen thalli, though a greater proportion of cells in the flight samples had compromised membranes, as revealed by the LIVE/DEAD BacLight Bacterial Viability Kit. These findings indicate that most lichenized fungal and algal cells can survive in space after full exposure to massive UV and cosmic radiation, conditions proven to be lethal to bacteria and other microorganisms. The lichen upper cortex seems to provide adequate protection against solar radiation. Moreover, after extreme dehydration induced by high vacuum, the lichens proved to be able to recover, in full, their metabolic activity within 24 hours.  相似文献   

15.
Space manipulators are complex systems, composed by robotic arms accommodated on an orbiting platform. They can be used to perform a variety of tasks: launch of satellites, retrieval of spacecraft for inspection, maintenance and repair, movement of cargo and so on. All these missions require extreme precision. However, in order to respect the mass at launch requirements, manipulators arms are usually very light and flexible, and their motion involves significant structural vibrations, especially after a grasping maneuver. In order to fulfill the maneuvers of space robotic systems it is hence necessary to properly model the forces acting on the space robot, from the main terms, such as the orbital motion, to the second order perturbations, like the gravity gradient and the orbital perturbations; also flexible excitation of the links and of the joints can be of great importance in the manipulators dynamics. The case is furthermore complicated by the fact that the manipulator, together with its supporting spacecraft, is an unconstrained body. Therefore the motion of any of its parts affects the entire system configuration. The governing equations of the dynamics of such robotic systems are highly nonlinear and fully coupled. The present paper aims at designing and studying active damping strategies and relevant devices that could be used to reduce the structural vibrations of a space manipulator with flexible links during its on orbit operations. In particular an optimized adaptive vibration control via piezoelectric devices is proposed. The number of piezoelectric devices, their placement and operational mode should be correctly chosen in order to obtain maximum performance in terms of elastic oscillations reduction and power consumption. Even though an optimal placement cannot have a universal validity, since it depends on the type of maneuver and on the overall inertial and geometrical characteristics, an approach to solve the problem is proposed.  相似文献   

16.
空间微小颗粒以低于临界黏附速度撞击卫星光学镜头时会附着在其表面,当大量的微粒黏附在卫星镜头上时会影响镜头的探测性能。精确计算临界黏附速度及找出影响临界黏附速度的因素对研究空间污染效率有着重要意义。在简化的EA模型的基础上,文章仿真分析了铜和石墨微粒撞击卫星镜头过程中的黏附力和临界黏附速度。结果表明:镜头表面粗糙度修正系数CR是影响黏附力和临界黏附速度的重要参数;在相同条件下,虽然石墨微粒受到的最大黏附力比铜微粒的小,但石墨微粒的临界黏附速度比铜微粒的高,说明石墨微粒更有可能黏附于镜头表面。  相似文献   

17.
The results of studying the interaction of two types of the solar wind (magnetic clouds and solar wind of extremely low density) with the Earth's magnetosphere are discussed. This study is based of the INTERBALL space project measurements and on the other ground-based and space observations. For moderate variations of the solar wind and interplanetary magnetic field (IMF) parameters, the response of the magnetosphere is similar to its response to similar changes in the absence of magnetic clouds and depends on a previous history of IMF variations. Extremely large density variations on the interplanetary shocks, and on leading and trailing edges of the clouds result in a strong deformation of the magnetosphere, in large-scale motion of the geomagnetic tail, and in the development of magnetic substorms and storms. The important consequences of these processes are: (1) the observation of regions of the magnetosphere and its boundaries at great distances from the average location; (2) density and temperature variations in the outer regions of the magnetosphere; (3) multiple crossings of geomagnetic tail boundaries by a satellite; and (4) bursty fluxes of electrons and ions in the magnetotail, auroral region, and the polar cap. Several polar activations and substorms can develop during a single magnetic cloud arrival; a greater number of these events are accompanied, as a rule, by the development of a stronger magnetic storm. A gradual, but very strong, decrease of the solar wind density on May 10–12, 1999, did not cause noticeable change of geomagnetic indices, though it resulted in considerable expansion of the magnetosphere.  相似文献   

18.
It is thought that the chiral molecules of living material can induce circular polarization in light at levels much higher than expected from abiotic processes. We therefore obtained high quality imaging circular polarimetry of the martian surface during the favorable opposition of 2003 to seek evidence of anomalous optical activity. We used two narrow-band filters covering 43% of the martian surface, 15% of it in-depth. With polarization noise levels <0.1% (4.3 upper limits 0.2-0.3%) and spatial resolution 210 km, we did not find any regions of circular polarization. When data were averaged over the observed face of the planet, we did see a small non-zero circular polarization 0.02%, which may be due to effects associated with the opposition configuration though it is at the limit of the instrumental capability. Our observations covered only a small fraction of parameter space, so although we obtained a null result, we cannot exclude the presence of optical activity at other wavelengths, in other locations, or at higher spatial resolution.  相似文献   

19.
The international community is entering an era of shared global utilities from space and is increasingly reliant on space systems and activities that support a myriad of applications and utilities on Earth. A growing number of states are seeking to develop or extend their space capabilities. At the same time, a variety of non-state actors are also extending their involvement in space activities. The United Nations is the principal inter-governmental forum to deal with various space issues of global importance. Moreover, the United Nations system itself has become increasingly reliant on space systems for its day-to-day operations. In order for the United Nations to play its necessary role in the space arena, it will need to be supported by a space policy. A United Nations space policy would provide over-arching guidance on space activities for UN stakeholders in the space arena; it would inform UN participation in space activities and would promote improved coordination and cooperative governance of outer space activities. A world without a common UN space policy will not be able to respond to the challenges of the rapidly evolving space arena in the 21st century.  相似文献   

20.
China's opaque politics present particular difficulties for US space policy. Heavily invested in and reliant on space, the US will closely monitor China's burgeoning space program. New space powers, and the increasing use of space generally will further create significant challenges, most particularly to the reliance of states on space for national security. In order to maintain its space capabilities, the US will have to decide between securing this via multilateral and co-operative uses of space, or through trying to maintain a level of dominance over other space actors. While very gradually shifting away from the latter position, Washington's policy choices are complicated by the lack of a clear Chinese space strategy. While the Chinese space program, and its wider intentions, are opaque, tenure of a more cooperative approach course might prove fragile.  相似文献   

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