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941.
The authors examine psychological issues and countermeasures in extended space flight. Individual-oriented pre-flight countermeasures include basic psychological selection and training of astronaut candidates. Crew-oriented pre-flight countermeasures include crew composition based on psychological compatibility and psychological mission preparation. Psychological inflight support measures include those that address the emotional state and well-being of astronauts, performance efficiency, and prevention of task overload. Suggestions for an integrated approach to psychological countermeasures for extended flights are presented. Case reports examine psychological selection and training of German astronauts in preparation for the STS-55 mission. 相似文献
942.
Wilde RC 《Acta Astronautica》1995,36(1):65-72
In today's fiscally constrained environment, it can be expected that systems designed for one space program will increasingly be used to support other programs. The example of the U.S. extravehicular mobility unit (EMU), designed for use with the Space Shuttle, and now part of the baseline for the International Space Station (ISS) program, illustrates the adaption process. Certifying the Shuttle's EMU for use aboard ISS requires addressing three fundamental issues: Identifying new ISS requirements to be imposed on the EMU. Extending Shuttle's EMU on-orbit service interval to meet ISS's longer missions. Certifying Shuttle's EMU to meet new environments unique to ISS. Upon completion of the certification process, Shuttle's EMU will meet all requirements for supporting both the Shuttle and ISS program. This paper discusses the processes for addressing these issues and progress to date in achieving resolution. 相似文献
943.
944.
A. B. Galvin F. M. Ipavich C. M. S. Cohen G. Gloeckler R. von Steiger 《Space Science Reviews》1995,72(1-2):65-70
The Ulysses mission now has an extensive data base covering several passes of the south polar coronal hole as the spacecraft proceeds to higher latitudes. Using composition measurements from the SWICS experiment on the Ulysses spacecraft, we have obtained charge state distributions, and hence inferred coronal ionization temperatures, for several solar wind species. In particular, we present an overview of Oxygen ionization temperature measurements, based on the O7+/O6+ ratio, for the period January 1993 until April 1994 (23°S to 61°S heliographic latitude), and detailed Oxygen, Silicon and Iron charge state distributions of the south polar hole during a two month period of nearly continuous hole coverage, Dec 1993–Jan 1994 (45°S to 52°S heliographic latitude). 相似文献
945.
We report the results of a study of the 12-hour average distribution functions of high Z nuclei as measured over a 10-day interval on the Ulysses spacecraft at a helioradius of5.2 A.U. We use the good time and atomic mass resolution of the composition aperture of the HI-SCALE instrument to determine the form of the distribution functions for C, O, Ne, Mg, Si, and Fe over the energy range 0.5–16 MeV/nucl. We find that the distribution functions of these ions can be organized by characteristic velocities that have values ranging between2000–3500 km/sec over this interval. 相似文献
946.
L R Young H Hecht L E Lyne K H Sienko C C Cheung J Kavelaars 《Acta Astronautica》2001,49(3-10):215-226
Short-radius centrifugation is a potential countermeasure to long-term weightlessness. Unfortunately, head movements in a rotating environment induce serious discomfort, non-compensatory vestibulo-ocular reflexes, and subjective illusions of body tilt. In two experiments we investigated the effects of pitch and yaw head movements in participants placed supine on a rotating bed with their head at the center of rotation, feet at the rim. The vast majority of participants experienced motion sickness, inappropriate vertical nystagmus and illusory tilt and roll as predicted by a semicircular canal model. However, a small but significant number of the 28 participants experienced tilt in the predicted plane but in the opposite direction. Heart rate was elevated following one-second duration head turns. Significant adaptation occurred following a series of head turns in the light. Vertical nystagmus, motion sickness and illusory tilt all decreased with adaptation. Consequences for artificial gravity produced by short-radius centrifuges as a countermeasure are discussed. Grant numbers: NCC 9-58. 相似文献
947.
Proton Events and X-ray Flares in the Last Three Solar Cycles 总被引:3,自引:0,他引:3
A database joining the available information about proton enhancements near the Earth and their possible solar sources is organized on the basis of proton measurements of the GOES and IMP-8 satellites, the data of neutron monitors, and GOES X-ray measurements. One thousand one hundred and forty-four proton events with energy > 10 MeV have been selected in the period from 1975 to 2003. More than a half of these events can be reliably related to X-ray solar flares. A statistical analysis shows the probability of observing solar protons near the Earth and their maximum flux value to be strongly dependent on the importance of a flare and its heliolongitude. Proton events are recorded after all suitably located (western) flares with X-ray importance > X5. The heliolongitude of a flare predetermines the character of the time profile of proton events in many respects. The relationship of proton events with the other characteristics of flares is established. The flares associated with proton enhancements are characterized by longer duration, slower rise to the X-ray maximum, smaller temperature, and larger length of the X-ray loops.__________Translated from Kosmicheskie Issledovaniya, Vol. 43, No. 3, 2005, pp. 171–185.Original Russian Text Copyright © 2005 by Belov, Garcia, Kurt, Mavromichalaki. 相似文献
948.
The Hidden Costs of Reliability and Failure in Launch Systems 总被引:1,自引:0,他引:1
In comparing the costs of different launch vehicles, the possibility of the risk of failure is assumed to be accounted for by the cost of insurance. The satellite may be insured against loss during launch, and the launch services provider may offer a free relaunch. However, actual costs of reliability and failure extend beyond this. Each failure necessitates an investigation and a get well programme by the operating agency, while putting the operations team on hold until services can resume. A commercial operator may also lose customer revenue and actual customers through loss of confidence or unavailability. Such costs tend to be hidden, and not evaluated in assessing the effectiveness of a system, but count towards total costs. Failure investigations help to improve system reliability, but this could equally have been achieved by expenditure in development and qualification. Reusable launch vehicles will have different costs associated with reliability and failure. The relationship between reliability and cost, properly assessed, ought to influence the design of both expendable and reusable launch systems. 相似文献
949.
Brownlee DE Tsou P Atkins KL Yen CW Vellinga JM Price S Clark BC 《Acta Astronautica》1996,39(1-4):51-60
The STARDUST Discovery mission will collect samples of cometary coma and interstellar dust and return them to Earth. Five years after launch in February 1999, coma dust in the 1- to 100-micrometers size range will be captured by impact into ultra-low-density silica aerogel during a 6 kms-1 flyby of Comet Wild 2. The returned samples will be investigated at laboratories where the most critical information on these primitive materials is retained. The Jet Propulsion Laboratory will provide project management with Lockheed Martin Astronauts as the spacecraft industrial partner. STARDUST management will aggressively and innovatively achieve cost control through the use of Total Quality Management principles, the chief of which will be organization in a Project Engineering and Integration Team that "flattens" the traditional hierarchical structure by including all project elements from the beginning, in a concurrent engineering framework focusing on evolving Integrated Mission Capability. 相似文献
950.
The willingness of the European Union (EU) to acquire an important position by defining a well articulated space policy for Europe requires a redefinition of the roles of the various actors of this policy. This has been demonstrated at the last ESA Ministerial Conference despite the financial difficulties encountered by all spacefaring European countries. The European Space Science Committee (ESSC), an associated Committee of the European Science Foundation (ESF), actively participated in the elaboration of such a policy by presenting the point of view of the space scientific community and making recommendations to ensure that scientific space research is appropriately accounted for in overall European space policy. The ESSC is briefly described along with its activities and contributions to the definition of a European space policy. 相似文献