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801.
802.
To investigate changes in spatial orientation ability and walking performance following space flight, 7 astronaut subjects were asked pre- and post-flight to perform a goal directed locomotion paradigm which consisted of walking a triangular path with and without vision. This new paradigm, involving inputs from different sensory systems, allows quantification of several critical parameters, like orientation performance, walking velocities and postural stability, in a natural walking task. The paper presented here mainly focusses on spatial orientation performance quantified by the errors in walking the previously seen path without vision. Errors in length and reaching the corners did not change significantly from pre- to post-flight, while absolute angular errors slightly increased post-flight. The significant decrease in walking velocity and a change in head-trunk coordination while walking around the corners of the path observed post-flight may suggest that during re-adaptation to gravity the mechanisms which are necessary to perform the task have to be re-accomplished.  相似文献   
803.
Highly mobile space suit material optimization   总被引:1,自引:0,他引:1  
This paper discusses the factors that control the flexibility of fabric space suit elements by examining a bending model of a pressurized fabric tube. Results from the model are used to evaluate the current direction in highly mobile EVA glove research and suggest that changes are necessary in the suit and glove fabric selection methodology.  相似文献   
804.
Bariteau  M.  Mandeville  J.-C. 《Space Debris》2000,2(2):97-107
When a micro-debris or a micrometeoroid impacts a spacecraft surface, a large number of secondary particles, called ejecta, are produced. These particles can contribute to a modification of the debris environment: either locally by the occurrence of secondary impacts on the components of complex and large space structures, or at great distance by the formation of a population of small orbital debris. This paper describes firstly, the ejecta overall production, and secondly, the lifetime and the orbital evolution of the particles. Finally the repartition of ejecta in LEO is computed. Some results describing the population as a function of size and altitude are presented.  相似文献   
805.
This paper discusses the errors in analyzing solar-terrestrial relationships, which result from either disregarding the types of interplanetary drivers in studying the magnetosphere response on their effect or from the incorrect identification of the type of these drivers. In particular, it has been shown that the absence of selection between the Sheath and ICME (the study of so-called CME-induced storms, i.e., magnetic storms generated by CME) leads to errors in the studies of interplanetary conditions of magnetic storm generation, because the statistical analysis has shown that, in the Sheath + ICME sequences, the largest number of storm onsets fell on the Sheath, and the largest number of storms maxima fell at the end of the Sheath and the beginning of the ICME. That is, the situation is observed most frequently when at least the larger part of the main phase of storm generation falls on the Sheath and, in reality, Sheath-induced storms are observed. In addition, we consider several cases in which magnetic storms were generated by corotating interaction regions, whereas the authors attribute them to CME.  相似文献   
806.
The work is devoted to observations of sharp growths of magnetospheric electron fluxes in the vicinity of the polar boundary of the outer radiation belt of the Earth according to the data of measurements on the Vernov and Lomonosov satellites. This precipitation was observed at the high-latitude boundary of the outer radiation belt toward the equator from the isotropization boundary, and can be caused by scattering waves of various physical natures, including electromagnetic and electrostatic waves.  相似文献   
807.
The RELEС scientific payload of the Vernov satellite launched on July 8, 2014 includes the DRGE spectrometer of gamma-rays and electrons. This instrument comprises a set of scintillator phoswich-detectors, including four identical X-ray and gamma-ray detector with an energy range of 10 kev to 3 MeV with a total area of ~500 cm2 directed to the atmosphere, as well as an electron spectrometer containing three mutually orthogonal detector units with a geometric factor of ~2 cm2 sr. The aim of a space experiment with the DRGE instrument is the study of fast phenomena, in particular Terrestrial gamma-ray flashes (TGF) and magnetospheric electron precipitation. In this regard, the instrument provides the transmission of both monitoring data with a time resolution of 1 s, and data in the event-by-event mode, with a recording of the time of detection of each gamma quantum or electron to an accuracy of ~15 μs. This makes it possible to not only conduct a detailed analysis of the variability in the gamma-ray range, but also compare the time profiles with the results of measurements with other RELEC instruments (the detector of optical and ultraviolet flares, radio-frequency and low-frequency analyzers of electromagnetic field parameters), as well as with the data of ground-based facility for thunderstorm activity. This paper presents the first catalog of Terrestrial gamma-ray flashes. The criterion for selecting flashes required in order to detect no less than 5 hard quanta in 1 ms by at least two independent detectors. The TGFs included in the catalog have a typical duration of ~400 μs, during which 10–40 gamma-ray quanta were detected. The time profiles, spectral parameters, and geographic position, as well as a result of a comparison with the output data of other Vernov instruments, are presented for each of candidates. The candidate for Terrestrial gamma-ray flashes detected in the near-polar region over Antarctica is discussed.  相似文献   
808.
809.
The use of wireless power transmission in Space Solar Power (SSP) activities creates significant policy issues regarding the beam right-of-way. There will not be a single beam, there may well be hundreds of beams for economical systems. Are some or all of these power beams to be afforded priorities of space for unobstructed power delivery, or must the beaming systems be designed to be capable of detecting any and all potential beam interceptions and appropriately responding? The repeated interruptions for guaranteed safety of transit for freely moving air and space traffic are of great consequence. The safety issues are critical, but the implications for equipment transient protection, energy storage system costs and the quality of power delivery service are also significant for wireless power transmission economics. A scenario of precursor wireless power transmission developments leading up to and including SSP applications will be used to frame and to discuss the beamed power technology implications and policy issues.  相似文献   
810.
Building an organization and management structure to create, launch, utilize and protect a satellite solar power energy system will require a global policy for the beneficial use of SSP. The fundamental organizational tasks are: (1) R&D, achieved through a project organization characterized by the integrated management of applied science, development research and construction engineering; (2) investment, generated by a series of groups creating financial vehicles for public and private investment; (3) transmission and distribution, characterized by attention to an engineering and maintenance process emphasizing high reliability; and (4) crisis response, demanding readiness for instant response to potential internal or external scenarios. A differentiated global organization spanning the long timeframe of SSP will need to have a central management core representative of all parts of the organization, with the capacity for self-renewal and re-adaptation. To be successful over its long timeframe, the SSP organization will need to build continuity and public confidence through intergenerational communication, public education, and community outreach. Integrating structures must be created at all levels of the organization, and should encompass joint work tasks and information-sharing among both industrial and government members. Developmental and alliance partners who support the formation and financing of a differentiated satellite solar power organization will share commensurately in the technologies and competencies that are created.  相似文献   
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