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621.
The started assembly of the International Space Station (ISS) and its further operation will call for a great number of extravehicular activity sorties (EVA) to be performed by ISS crews. Therefore, of great importance is to make use of the EVA experience gained by cosmonauts in the process of 15-year operation of the Mir orbiting station (OS). Over the 15-year period, Mir crewmembers wearing Orlan type semi-rigid space suits have accumulated 158 man/sorties from the orbiting station. Crewmembers used 15 suits in orbit and some of the suits were in operation for more than 3 years. The paper presents principal design features, which provide effective and safe operation of orbit-based suits, and briefly describes procedures for preparation and maintenance of suit systems, which ensure long-term operation of space suit in orbit. The paper gives results of the space suit modifications, presents suit performance characteristics and lists novel or upgraded components of the space suit and its systems. The paper also summarizes improvements in the Orlan type suits described in some earlier publications. They refer, in the first run, to the improvement of space suit operations characteristics and reliability, and the utilization of the Orlan type space suit in the ISS program. The paper analyses the experience gained and drawbacks detected and observations made, and gives statistical data on long-term space suit operations aboard the Mir station. The paper reviews certain problems in the process of EVAs performed from the station, and describes the ways of their solution as applied to the further utilization of the suit within the ISS program. 相似文献
622.
V Bidoli M Casolino M P De Pascale G Furano A Morselli L Narici P Picozza E Reali R Sparvoli A M Galper A V Ozerov YuVPopov N R Vavilov A P Alexandrov S V Avdeev Y u Baturin Y u Budarin G Padalko V G Shabelnikov G Barbellini W Bonvicini A Vacchi N Zampa S Bartalucci G Mazzenga M Ricci O Adriani P Spillantini M Boezio P Carlson C Fuglesang G Castellini W G Sannita 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2000,25(10):2075-2079
The SilEye experiment aims to study the cause and processes related to the anomalous Light Flashes (LF) perceived by astronauts in orbit and their relation with Cosmic Rays. These observations will be also useful in the study of the long duration manned space flight environment. Two PC-driven silicon detector telescopes have been built and placed aboard Space Station MIR. SilEye-1 was launched in 1995 and provided particles track and LF information; the data gathered indicate a linear dependence of FLF(Hz) ( 4 2) 10(3) 5.3 1.7 10(4) Fpart(Hz) if South Atlantic Anomaly fluxes are not included. Even though higher statistic is required, this is an indication that heavy ion interactions with the eye are the main LF cause. To improve quality and quantity of measurements, a second apparatus, SilEye-2, was placed on MIR in 1997, and started work from August 1998. This instrument provides energetic information, which allows nuclear identification in selected energy ranges; we present preliminary measurements of the radiation field inside MIR performed with SilEye-2 detector in June 1998. 相似文献
623.
Cognitive performance aboard the life and microgravity spacelab 总被引:2,自引:0,他引:2
The impact of microgravity and other stressors on cognitive performance need to be quantified before long duration space flights are planned or attempted since countermeasures may be required. Four astronauts completed 38 sessions of a 20-minute battery of six cognitive performance tests on a laptop computer. Twenty-four sessions were preflight, 9 sessions were in-orbit, and 5 sessions were postflight. Mathematical models of learning were fit to each subject's preflight data for each of 14 dependent variables. Assuming continued improvement, expected values were generated from the models for in-orbit comparison. Using single subject designs, two subjects showed statistically significant in-orbit effects. One subject was degraded in two tests, the other was degraded in one test and exceeded performance expectations in another. Other subjects showed no statistically significant effects on the tests. The factors causing the deterioration in the two subjects can not be determined without appropriate ground-based control groups. 相似文献
624.
We evaluated the influence of prolonged weightlessness on the performance of three cosmonauts to bilateral symmetry detection in the course of a 15-day-long Russian-French mission CASSIOPEE 96 aboard the MIR station. We tested the influence of weightlessness on subjects' performance as a function of the retinal orientation of axis of symmetry. as a function of type of stimuli (closed versus multi-elements shapes) and as a function of visual field presentation (at fixation, left visual field. right visual field). The results indicate firstly a difference between presentation at fixation versus away of fixation. Away of fixation, no effect of microgravity on performance was shown. A hypothesis of hemispheric specialization for symmetry detection was not supported as well. At fixation, an effect of micro-gravity was shown and more interestingly, the effect was quite different as a function of type of shapes used. suggesting that symmetry detection is a multiple-stage process. 相似文献
625.
P Todd D M Klaus L S Stodieck J D Smith L A Staehelin M Kacena B Manfredi A Bukhari 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》1998,21(8-9):1263-1268
Our understanding of gravitational effects (inertial effects in the vicinity of 1 x g) on cells has matured to a stage at which it is possible to define, on the basis of experimental evidence, extracellular effects on small cells and intracellular effects on eukaryotic gravisensing cells. Yet undetermined is the nature of response, if any, of those classes of cells that are not governed solely by extracellular physical events (as are prokaryotes) and are devoid of obvious mechanical devices for sensing inertial forces (such as those possessed by certain plant cells and sensory cells of animals). This "in-between" class of cells needs to be understood on the basis of the combination of intracellular and extracellular gravity-dependent processes that govern experimentally-measurable variables that are relevant to the cell's responses to modified inertial forces. The forces that certain cell types generate or respond to are therefore compared to those imposed by approximately 1 x g in the context of cytoskeletal action and symmetry-breaking pathways. 相似文献
626.
A.V. Pavlov N.M. Pavlova 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2013
Hourly values of the F2-layer peak density, NmF2, measured by 95 ionosondes near noon from 1957 to 2011 at low and middle geomagnetic latitudes of the northern and southern geographic hemispheres are used in a statistical study of the NmF2 equinoctial asymmetry. The ratios, R, of NmF2 measured during 61 days around the March equinox to NmF2 measured during 61 days around the September equinox at the same UT near noon during geomagnetically quiet daytime conditions for approximately the same solar activity conditions over the same ionosonde are analyzed. The conditional probability of the occurrence of R in an interval of R, the most probable value of R, and the mean expected value of R are calculated for the first time for the low, moderate, and high solar activity levels to study variations in these statistical parameters with latitude and solar activity. These statistical parameters are averaged over 5° geomagnetic latitude interval in the northern and southern geographic hemispheres to calculate and to study for the first time trends in latitude and solar activity of these averaged NmF2 equinoctial asymmetry statistical characteristics. 相似文献
627.
W. Menn O. Adriani G.C. Barbarino G.A. Bazilevskaya R. Bellotti M. Boezio E.A. Bogomolov L. Bonechi M. Bongi V. Bonvicini S. Borisov S. Bottai A. Bruno F. Cafagna D. Campana R. Carbone P. Carlson M. Casolino G. Castellini L. Consiglio M.P. De Pascale C. De Santis N. De Simone V. Di Felice A.M. Galper W. Gillard L. Grishantseva G. Jerse A.V. Karelin S.V. Koldashov S.Y. Krutkov A.N. Kvashnin A. Leonov V. Malakhov V. Malvezzi L. Marcelli A.G. Mayorov V.V. Mikhailov E. Mocchiutti A. Monaco N. Mori N. Nikonov G. Osteria F. Palma P. Papini M. Pearce P. Picozza C. Pizzolotto M. Ricci S.B. Ricciarini 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2013
628.
Security applications of computer vision 总被引:1,自引:0,他引:1
In an age which bears witness to a proliferation of Closed Circuit Television (CCTV) cameras for security and surveillance monitoring, the use of image processing and computer vision techniques which were provided as top end bespoke solutions can now be realised using desktop PC processing. Commercial Video Motion Detection (VMD) and Intelligent Scene Monitoring (ISM) systems are becoming increasingly sophisticated, aided, in no small way, by a technology transfer from previously exclusively military research sectors. Image processing is traditionally concerned with pre-processing operations such as Fourier filtering, edge detection and morphological operations. Computer vision extends the image processing paradigm to include understanding of scene content, tracking and object classification. Examples of computer vision applications include Automatic Number Plate Recognition (ANPR), people and vehicle tracking, crowd analysis and model based vision. Often image processing and computer vision techniques are developed with highly specific applications in mind and the goal of a more global understanding computer vision system remains, at least for now, outside the bounds of present technology. This paper will review some of the most recent developments in computer vision and image processing for challenging outdoor perimeter security applications. It also describes the efforts of development teams to integrate some of these advanced ideas into coherent prototype development systems 相似文献
629.
630.
N.V. Kuznetsov N.I. Nikolaeva 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2010
The proton fluxes from the low-Earth orbital satellites databases (NPOES-17 and CORONAS-F) were analyzed for the quiet geomagnetic period in April 2005. The satisfactory consent was found between the experimental and the AP8 model fluxes of the trapped protons with energy more than ∼10 MeV. At the same time, trapped proton fluxes with energy less than 10 MeV measured by LEO satellites were higher than the ones predicted by the AP8 model in the region of the SAA (drift shell L < 1.5). 相似文献