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1.
The COSAC (Cometary Sampling and Composition Experiment) onboard the Rosetta mission is a combined gas chromatograph (GC)-mass spectrometer (MS). It is situated on Philae, the lander of the mission, which is intended to land on the nucleus of comet 67P/Churyumov- Gerasimenko. The purpose of the experiment is to analyze the volatile fraction of soil samples retrieved by a drill. For investigation, the samples will be pyrolysed, and the emanating gases fed into a GC, into an MS, or the combination of both. In the first part of this paper, the bioastronomical relevance of such measurements is outlined. In the second part the details of the hardware and its performance are described. 相似文献
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In the past two years, NASA has begun to develop and implement plans for investigations on robotic Mars missions which are focused toward returning data critical for planning human missions to Mars. The Mars Surveyor Program 2001 Orbiter and Lander missions will mark the first time that experiments dedicated to preparation for human exploration will be carried out. Investigations on these missions and future missions range from characterization of the physical and chemical environment of Mars, to predicting the response of biology to the Mars environment. Planning for such missions must take into account existing data from previous Mars missions which were not necessarily focused on human exploration preparation. At the same time, plans for near term missions by the international community must be considered to avoid duplication of effort. This paper reviews data requirements for human exploration and applicability of existing data. It will also describe current plans for investigations and place them within the context of related international activities. 相似文献
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Disaster events have always been with us. Success or failure of a disaster response is often determined by timely access to communication and the exchange of reliable information. Especially, crucial is information acquired by on-site first responders responsible for initial disaster assessment. The rapid progress in satellite communication development is laying a foundation for a future where lack of communications will no longer be a limiting or paralyzing factor in disaster response. This paper discusses emerging satellite communications tools that can enhance on site assessment and change the way disaster management is viewed and carried out in the next century. 相似文献
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In spite of the spectacular developments in our understanding of the molecular basis that underlies biological phenomena, we still lack a generally agreed-upon definition of life, but this is not for want of trying. Life is an empirical concept; and, as suggested by the many unsuccessful efforts to define it, this task is likely to remain, at best, a work in progress. Although phenomenological characterizations of life are feasible, a precise definition of life remains an elusive intellectual endeavor. This is not surprising: as Nietszche once wrote, there are concepts that can be defined, whereas others only have a history. The purpose of this essay is to discuss some of the manifold (and often unsatisfactory) definitions of life that have been attempted from different intellectual and scientific perspectives and reflect, at least in part, the key role that historical frameworks play. Although some efforts have been more fruitful, the lack of an all-embracing, generally agreed-upon definition of life sometimes gives the impression that what is meant by life's origin is defined in somewhat imprecise terms and that several entirely different questions are often confused. The many attempts made to reduce the nature of living systems to a single living compound imply that life can be so well defined that the exact point at which it started can be established with the sudden appearance of the first replicating molecule. On the other hand, if the emergence of life is seen as the stepwise (but not necessarily slow) evolutionary transition between the non-living and the living, then it may be meaningless to draw a strict line between them. 相似文献
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针对常用的卫星通信信号的调制方式识别问题,提出了一种新的自动识别算法.该算法基于统计特性分类原理,通过建立一组统计特征参数,在无需先验信息的条件下,实现对信号调制方式的自动识别.对实际采集数据进行了实验验证,结果表明该算法在低信噪比环境下仍有较高的识别率,简单易用,具有较强的工程可行性和良好的扩展性. 相似文献
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在今年的全国空管工作会议上,苏兰根局长再一次阐述了空管系统“三横三纵”体系建设的重要性及“三横三纵”体系建设的目标、原则和思路,并强调指出在当前和今后一段时期,空管系统要牢固树立持续安全理念,以“三横三纵”体系建设为重点,以完善一体化建设为保障,建立符合航空运输发展需求的空中交通管理系统。苏局长关于“三横三纵”体系的论述,是全面落实科学发展观,保证空管持续安全、促进空管系统又好又快发展的重要指导思想,同时也是空管一体化后,在科学分析当前空管事业发展的阶段性特征和形势做出的创新性和前瞻性的战略决策。 相似文献
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Laurance R. Doyle Brenda McCowan Simon Johnston Sean F. Hanser 《Acta Astronautica》2011,68(3-4):406-417
We present ongoing research in the application of information theory to animal communication systems with the goal of developing additional detectors and estimators for possible extraterrestrial intelligent signals. Regardless of the species, for intelligence (i.e., complex knowledge) to be transmitted certain rules of information theory must still be obeyed. We demonstrate some preliminary results of applying information theory to socially complex marine mammal species (bottlenose dolphins and humpback whales) as well as arboreal squirrel monkeys, because they almost exclusively rely on vocal signals for their communications, producing signals which can be readily characterized by signal analysis. Metrics such as Zipf's Law and higher-order information-entropic structure are emerging as indicators of the communicative complexity characteristic of an “intelligent message” content within these animals’ signals, perhaps not surprising given these species’ social complexity. In addition to human languages, for comparison we also apply these metrics to pulsar signals—perhaps (arguably) the most “organized” of stellar systems—as an example of astrophysical systems that would have to be distinguished from an extraterrestrial intelligence message by such information theoretic filters. We also look at a message transmitted from Earth (Arecibo Observatory) that contains a lot of meaning but little information in the mathematical sense we define it here. We conclude that the study of non-human communication systems on our own planet can make a valuable contribution to the detection of extraterrestrial intelligence by providing quantitative general measures of communicative complexity. Studying the complex communication systems of other intelligent species on our own planet may also be one of the best ways to deprovincialize our thinking about extraterrestrial communication systems in general. 相似文献
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航管内话系统主要功能为集成地空(ground/air)和地地(ground/ground)通信于一个控制台上,为使用者提供多种话音通信方式,包括电话、热线电话、席位电话及VHF通信,便于管制员进行指挥和控制,提高工作效率。其基本结构大致分为:主机、管制席位、监控终端、无线接口、有线接口、录音接口及主配线架。其系统结构图如图1所示。 相似文献
10.
State of the art, lightweight scientific experiments available for small to micro satellite missions
A selection of light weight scientific instruments originally designed for major international missions but which, because of their modest resource requirements, can now in addition be flown aboard ‘small’ to ‘micro’ satellites are, briefly, described. These instruments have the capability to either make measurements of constituents of the Earth's energetic particle environment, or provide detailed monitoring of multiple parameters of the cold terrestrial ionospheric plasma. Scientific reasons for flying such instruments in LEO are, in each case, advanced. Individually, they constitute representative examples of a mature genre of commercially available (a cost parameter of £100k/kg can be achieved), light weight, space qualified, instruments which can contribute significantly to the implementation of first class scientific programs aboard small/micro satellites. Uniquely fault tolerant data processing units are a feature of these devices. 相似文献
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随着我国民航业的快速发展,和谐空管建设对做好空管青年职工和共青团工作提出了新的时代要求。作为空管系统的基层团干部,应该站在时代的前列,奋发有为,不辱使命,不负重托,团结和带领广大青年团员,为空管事业的又好又快发展而努力奋斗。 相似文献
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Barmin I Bryukhanov N Egorov A Filatov I Markov A Senchenkov A Tsvetkov V 《Acta Astronautica》2002,51(1-9):255-259
The problem is considered of using the PROGRESS transport spacecraft, which will deliver the payload on the ISS, as a free flying platform for realization of space experiments. For maintenance of the ISS 5-6 PROGRESS flights per year are planned. Usually after delivery of the payload the PROGRESS undocks from the ISS and burns down in the Earth atmosphere. However, the operating conditions of its onboard systems allow to prolong operation and to make free flight near to the station and repeatedly to be docked to it. It is offered to use this possibility for performing experiments on Material Science. 相似文献
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In 1994-1995 Lavochkin Association (Russia) together with the other enterprises in accordance with technical requirements of the Russian Space agency, developed a new Russian communication satellite of a small class that will operate in both the geostationary (GSO) and high-elliptical (HEO) orbits. This satellite may be injected into operational orbits using a SOYUZ-2 launch vehicle (LV) and a FREGAT upper stage (US) from Plesetsk and Baykonur space launch sites (SLS).The main reason for creating such a satellite was to decrease the cost of the support and development of the Russian communication geostationary satellites group.Russian satellites Horizont, Express, Ekran and Gals, which operate in GSO, are the basis of the space segment for communications, radio and TV broadcasting. All of these satellites are injected into GSO by the PROTON LV. PROTON is a launch vehicle of a heavy class. The use of a middle class LV instead of a heavy class will allow to reduce considerably the launch cost. The change of a heavy class LV to a LV of middle class determined one economic reason for this project. Besides, the opportunity to launch S/C into GSO from Russian Plesetsk SLS increases the independence of Russia in the domain of space communications, despite the presence of the contract with Kazachstan about the rent of Baykonur SLS. Finally, use of small satellites with a rather small number of transponders is more effective than the use of big satellites. It will allow also to increase a satellite group (by the launch of additional satellites) precisely in accordance to the development of the ground segment. 相似文献
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Ahmed Bounfour 《Space Policy》1994,10(4):290-306
This paper refers to a study (specificaly to its chapter 7)1 carried out by Euroconsult for ESA on the key characteristics of European R&D in the satellite communications user Earth segment. The study was initiated by the Working Group on Satellite Communications Policy2 of the Joint Board on Communications Satellite Programmes (JCB), which was established by the Director General of ESA in July 1990 to contribute to the European agency's response to the EC Green Paper. The working group specifically expresses the European space communications industry's point of view. 相似文献
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引言无线电陆空通话(RTF,radio telephone)作为航空专用交际语言,它传递着管制员与机组之间的指令信息,是空中交通管制员(以下简称管制员)发布管制指令,提供航行情报和告警服务的载体,也 相似文献
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上海航天技术研究院在神舟飞船研制中取得的科研成果 总被引:1,自引:0,他引:1
通过神舟飞船的研制,上海航天技术研究院在飞船电源分系统、推进分系统、测控与通信分系统、推进舱等关键系统和产品的研制工作中探索并总结出了国内领先的专业技术成果,确保了神舟飞船研制目标实现。 相似文献
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New roles in space for the 21st century: a Uruguayan view 总被引:1,自引:0,他引:1
In the economic and social circumstances of the 21st century globalized world, there is a need to rethink the traditional roles and positions in space of international intergovernmental organizations, states, both developed and developing, and humankind itself. Uruguay provides an example of a non-typical country that has managed to carve an important niche for itself in the field of space law. Although globalization is an irreversible phenomenon, which has had a devastating effect on the weakest countries, following the attacks of 11 September 2001 insecurity has become globalized for everyone. From the point of view of a state such as Uruguay, this crisis must be looked upon as an opportunity to renew and inspire intelligence, education and culture. In this way—and by continuing to argue for a global space organization—it can contribute to making the Space Age an era of global and planetary solidarity for the benefit of humankind. 相似文献
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Experiments on the quick-relief medical communications via the CS-2 satellite were carried out by using two types of 30/20 GHz small transportable earth stations whose antenna diameters are 1 and 2 m. As the terminal equipments, FM-SCPC systems with a one-telephone-equivalent channel were prepared for the transmission of voice, color freezed picture (9.6 kbps), supersonic echo signal and heart sound from a electrocardiograph. Signals from various medical equipments were transmitted by an FM-SCPC system from Simizu harbour (1 m station) to Tokyo transportable station (2 m), assuming that a person was injured in the ship and the ship came alongside the pier. Transmitted materials are mainly various kinds of pictures of affected parts, X-ray films and electrocardiograph with breathing sounds. It was found possible to send various medical information mentioned above via CS-2 by the 30/20 GHz simple communication systems with one-telephone-equivalent channel. Doctors suggested it would be possible to judge very well about the patients' emergency conditions and to give quick consult with inevitable treatment procedures for them. However, a few problems were found in the Hi-Fi reproduction of original colors and in the transmission of heart sounds in the very low frequency band less than 300 Hz. 相似文献