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321.
N. Parihar G.K. Mukherjee 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2008,41(4):660-669
The paper reports the nightglow observations of hydroxyl (8–3), (7–2) and (6–2) Meinel band carried out at a low latitude station Kolhapur (16.8°N, 74.2°E, dip latitude 10.6°N), India during November 2002 to May 2005 with the objective of investigating mesopause dynamics based on derived OH rotational temperature. Overall, 132 nights of quality data were collected using filter-tilting photometer and an all-sky scanning photometer. The mean mesopause temperature observed at Kolhapur is 195 ± 11, 196 ± 9 and 195 ± 7 K from OH (8–3), (7–2) and (6–2) band emissions, respectively, using transition probabilities given by Langhoff et al. [Langhoff, S.R., Werner, H.J., Rosmus, P. Theoretical transition probabilities for the OH Meinel system. Journal of Molecular Spectroscopy 118, 507–529, 1986]. Small wave-like variations (periodicities ∼ few hours) existing over long period variations in derived temperatures are also present. A steady decrease of emission intensities from evening to dawn hours has been observed in approximately 59% of nights. No significant change of nightly mean temperatures has been noted. Furthermore, about 62% of observed nightly mean temperatures lie within one error bar of MSISE-90 model predictions. 相似文献
322.
H.N. Wang Y.M. Cui R. Li L.Y. Zhang H. Han 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2008,42(9):1464-1468
Nowadays operational models for solar activity forecasting are still based on the statistical relationship between solar activity and solar magnetic field evolution. In order to set up this relationship, many parameters have been proposed to be the measures. Conventional measures are based on the sunspot group classification which provides limited information from sunspots. For this reason, new measures based on solar magnetic field observations are proposed and a solar flare forecasting model supported with an artificial neural network is introduced. This model is equivalent to a person with a long period of solar flare forecasting experience. 相似文献
323.
N Desai H Wu K George S R Gonda F A Cucinotta 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2004,34(6):1362-1367
Space flight results in the exposure of astronauts to a mixed field of radiation composed of energetic particles of varying energies, and biological indicators of space radiation exposure provides a better understanding of the associated long-term health risks. Current methods of biodosimetry have employed the use of cytogenetic analysis for biodosimetry, and more recently the advent of technological progression has led to advanced research in the use of genomic and proteomic expression profiling to simultaneously assess biomarkers of radiation exposure. We describe here the technical advantages of the Luminex(TM) 100 system relative to traditional methods and its potential as a tool to simultaneously profile multiple proteins induced by ionizing radiation. The development of such a bioassay would provide more relevant post-translational dynamics of stress response and will impart important implications in the advancement of space and other radiation contact monitoring. 相似文献
324.
M.M. Gogoshev Ts.N. Gogosheva I.N. Kostadinov T.I. Markova Sl. Kisyovski 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》1985,5(4):213-216
The region of South Atlantic Geomagnetic Anomaly (SAGA) was investigated by the Intercosmos-Bulgaria-1300 satellite, launched on August 7, 1981. On the basis of data obtained from 15 orbits during increased geomagnetic activity in August 1981, a map of the Anomaly was elaborated. Two centres of activity were identified. By means of the EMO-5 electrophotometer on board the Intercosmos-Bulgaria-1300 satellite, the atmosphere glow in lines λ 5577 Å, λ 6300 Å and λ 4278 Å was studied. 相似文献
325.
H.G. Mayr I. Harris F.A. Herrero N.W. Spencer A.E. Hedin R.E. Hartle H.A. Taylor L.E. Wharton F. Varosi H. Volland G.R. Carignan 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》1985,5(4):283-288
Thermospheric temperature, composition and wind measurements from the Dynamics Explorer satellite (DE-2) are interpreted using a three dimensional, multiconstituent spectral model. The analysis accounts for tides driven by the absorbed solar radiation as well as energy and momentum coupling involving the magnetosphere and lower atmosphere. We discuss phenomena associated with the annual tide, polar circulation, magnetic storms and substorms. 相似文献
326.
H. Fuke J.E. Koglin T. Yoshida T. Aramaki W.W. Craig L. Fabris F. Gahbauer C.J. Hailey F.J. Jou N. Madden K. Mori H.T. Yu K.P. Ziock 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2008,41(12):2056-2060
We discuss current progress and future plans for the general antiparticle spectrometer experiment (GAPS). GAPS detects antideuterons through the X-rays and pions emitted during the deexcitation of exotic atoms formed when the antideuterons are slowed down and stopped in targets. GAPS provides an exceptionally sensitive means to detect cosmic-ray antideuterons. Cosmic-ray antideuterons can provide indirect evidence for the existence of dark matter in such form as neutralinos or Kaluza–Klein particles. We describe results of accelerator testing of GAPS prototypes, tentative design concepts for a flight GAPS detector, and near-term plans for flying a GAPS prototype on a balloon. 相似文献
327.
I.V. Muralikrishna 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》1985,5(5):111-114
The needs of coastal engineering are different from open ocean monitoring or fisheries potential monitoring. A high resolution of 20 meters is essential for identifying several processes that are taking place and influences the coast. A case of application of Landsat MSS to evaluate littoral process highlights the needs for improved spatial resolution. Nevertheless Landsat MSS data for 1981 and 1982 showed that the extent of accretion and erosion that has taken place during this period. Some problems to be addressed for marine remote sensing are mainly regarding the need for insitu data. These aspects are mentioned. 相似文献
328.
Samuel N. Goward 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》1985,5(5):41-50
Shortwave infrared sensors were included on Thematic Mapper to observe vegetation reflected radiance patterns that are related to leaf water content. However, there was some uncertainty whether these measurements would increase the information content of multispectral measurements beyond that provided by visible and near infrared measurements. Analysis of field measurements for corn and soybeans observed throughout the growing season shows that shortwave infrared measurements enhance discrimination between these species, particularly in mid-season. Modeling the canopy reflectances shows that differential leaf absorptance can produce the observed pattern. Analysis of coincident aerial photography suggests that within canopy shadowing is also important. Too few studies of leaf optical properties have been conducted to permit generalization of the results to other vegetation species but the results do show that shortwave infrared measurements contribute new information about vegetation not previously available in visible and near infrared measurements. 相似文献
329.
V.E. Zuev S.I. Kavkyanov G.M. Krekov 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》1985,5(6):81-85
A single-frequency lidar, using aerosol scattering as an informative component, is the simplest and reliable facility for remote sensing of the atmosphere. The information on vertical distribution of atmospheric aerosol which can be obtained using such a lidar is necessary for investigating the physics of atmospheric processes and forecast of optical state of the atmosphere. At the same time, the interpretation of data on single-frequency sounding is associated with some difficulties of fundamental character, mainly due to insufficient software of the experiment. Under such conditions the problems of optimal processing of lidar returns aiming at extracting the useful information on aerosol are of great importance, especially if one takes into account the hindering effects of atmospheric background and optical noises. This paper presents a statistical approach to this problem, and the possibilities of single-frequency sounding from space are analyzed. 相似文献
330.
G.J. Nagy D.N. Severov V.A. Pshennikov M. De los Santos J.J. Lagomarsino K. Sans E.G. Morozov 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2008,41(11):1876-1881
This paper deals with the application of SeaWIFS images to characterize spatial and temporal variability of fronts in the Rio de la Plata estuarine system over the period 2000–2003. We aim to depict the relationship between river outflow and variability of fronts’ loci on monthly to ENSO-related timescales and the influence of the winds along Rio de la Plata (axial winds) on the abrupt changes in frontal dynamics over synoptic timescales. During the studied period both La Niña (July 1999–June 2000) and El Niño (April 2002–May 2003) events induced significant displacements of fronts. Three distinct fronts were analyzed between river, estuarine, coastal and marine waters of the Rio de la Plata: Main Turbidity Front, Main Marine Front, and Secondary Marine Front. Their number, location and separation seem to be mainly related to river outflow and second, to fresh (>8 m/s) axial winds. During low discharge periods (i.e. summer time and/or La Niña events) these winds induce abrupt changes in the location of fronts (100–200 km) and greater separation between them over synoptic timescale, whereas during high river discharge or ENSO years some of the variability of fronts location is explained by the river’s outflow fluctuations, especially by the high variability of the River Uruguay discharge. 相似文献