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791.
792.
Vladimir N. Melnikov 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2010
The aim of the study is to explore whether age at death from cardiovascular diseases depends on solar and geomagnetic activities. The data were collected for 1970–1978 in Novosibirsk, West Siberia, for industrial workers of Siberian origin. The Spearman correlations are computed between linearly detrended lifespan and daily or monthly physical variables to establish immediate (lag, L = 0), delayed (L = 1–3 days) and cumulative (L = ±30 days) influences. Significant correlations ranging from r = −0.26 to r = −0.30 for L from 0 to 3, respectively, are found for men between solar radio flux at wavelength 10.7 cm and age at death from acute myocardial infarction (AMI) but not from acute heart failure, ischemic heart disease and stroke. For AMI, women’s longevity displays an opposite (direct) association with the average solar character occurred at the calendar month of death. The index of geomagnetic activity, Ap, exhibits inverse association with longevity for the AMI stratum for both sexes. GLM univariate procedure revealed higher contribution of Ap to the variance of lifespan compared to season of death. The individual age at death susceptibility to cosmic influences is found to depend upon solar activity at year of birth. It is concluded that associations between the lifespan for cardiovascular decedents and the indices of solar and geomagnetic activities at time of death and of birth are cause-of-death- and sex-specific. 相似文献
793.
M.N. Kouahla G. Moreels M. Faivre J. Clairemidi J.W. Meriwether G.A. Lehmacher E. Vidal O. Veliz 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2010
A new and original stereo imaging method is introduced to measure the altitude of the OH nightglow layer and provide a 3D perspective map of the altitude of the layer centroid. Near-IR photographs of the OH layer are taken at two sites separated by a 645 km distance. Each photograph is processed in order to provide a satellite view of the layer. When superposed, the two views present a common diamond-shaped area. Pairs of matched points that correspond to a physical emissive point in the common area are identified in calculating a normalized cross-correlation coefficient (NCC). This method is suitable for obtaining 3D representations in the case of low-contrast objects. An observational campaign was conducted in July 2006 in Peru. The images were taken simultaneously at Cerro Cosmos (12°09′08.2″ S, 75°33′49.3″ W, altitude 4630 m) close to Huancayo and Cerro Verde Tellolo (16°33′17.6″ S, 71°39′59.4″ W, altitude 2272 m) close to Arequipa. 3D maps of the layer surface were retrieved and compared with pseudo-relief intensity maps of the same region. The mean altitude of the emission barycenter is located at 86.3 km on July 26. Comparable relief wavy features appear in the 3D and intensity maps. It is shown that the vertical amplitude of the wave system varies as exp (Δz/2H) within the altitude range Δz = 83.5–88.0 km, H being the scale height. The oscillatory kinetic energy at the altitude of the OH layer is comprised between 3 × 10−4 and 5.4 × 10−4 J/m3, which is 2–3 times smaller than the values derived from partial radio wave at 52°N latitude. 相似文献
794.
I. G. Mitrofanov A. Bartels Y. I. Bobrovnitsky W. Boynton G. Chin H. Enos L. Evans S. Floyd J. Garvin D. V. Golovin A. S. Grebennikov K. Harshman L. L. Kazakov J. Keller A. A. Konovalov A. S. Kozyrev A. R. Krylov M. L. Litvak A. V. Malakhov T. McClanahan G. M. Milikh M. I. Mokrousov S. Ponomareva R. Z. Sagdeev A. B. Sanin V. V. Shevchenko V. N. Shvetsov R. Starr G. N. Timoshenko T. M. Tomilina V. I. Tretyakov J. Trombka V. S. Troshin V. N. Uvarov A. B. Varennikov A. A. Vostrukhin 《Space Science Reviews》2010,150(1-4):183-207
The design of the Lunar Exploration Neutron Detector (LEND) experiment is presented, which was optimized to address several of the primary measurement requirements of NASA’s Lunar Reconnaissance Orbiter (LRO): high spatial resolution hydrogen mapping of the Moon’s upper-most surface, identification of putative deposits of appreciable near-surface water ice in the Moon’s polar cold traps, and characterization of the human-relevant space radiation environment in lunar orbit. A comprehensive program of LEND instrument physical calibrations is discussed and the baseline scenario of LEND observations from the primary LRO lunar orbit is presented. LEND data products will be useful for determining the next stages of the emerging global lunar exploration program, and they will facilitate the study of the physics of hydrogen implantation and diffusion in the regolith, test the presence of water ice deposits in lunar cold polar traps, and investigate the role of neutrons within the radiation environment of the shallow lunar surface. 相似文献
795.
Geomagnetic Core Field Secular Variation Models 总被引:1,自引:0,他引:1
We analyse models describing time changes of the Earth’s core magnetic field (secular variation) covering the historical period (several centuries) and the more recent satellite era (previous decade), and we illustrate how both the information contained in the data and the a priori information (regularisation) affect the result of the ill-posed geomagnetic inverse problem. We show how data quality, frequency and selection procedures govern part of the temporal changes in the secular variation norms and spectra, which are sometimes difficult to dissociate from true changes of the core state. We highlight the difficulty of resolving the time variability of the high degree secular variation coefficients (i.e. the secular acceleration), arising for instance from the challenge to properly separate sources of internal and of external origin. In addition, the regularisation process may also result in artificial changes in the model norms and spectra. Model users should keep in mind that such features can be mis-interpreted as the signature of physical mechanisms (e.g. diffusion). Finally, we present perspectives concerning core field modelling: imposing dynamical constraints (e.g. by means of data assimilation) reduces the non-uniqueness of the geomagnetic inverse problem. 相似文献
796.
797.
A. P. Paramonov 《Russian Aeronautics (Iz VUZ)》2010,53(2):121-125
Problems of improving the efficiency of design works in the process of space-rocket complex (SRC) updating are considered.
The methodical foundation for the expert system application to form promising technical solutions in studying the flight vehicle
(FV) modification is presented. 相似文献
798.
Basic principles of a mathematical model for disk-wing aircraft balancing and evaluation of power expenditure for flight as
compared with a helicopter are presented. 相似文献
799.
Methodology of constructing a stationary multichannel flow aerometric receiver using the effects of deceleration and throttling
of an incoming airflow and their circular transformation in the yaw plane is considered. The mathematical models and algorithms
for processing primary informative signals entering along the channels of speed, altitude, angles of attack and slip of the
helicopter air data system constructed on the basis of the aerometric receiver being proposed are obtained. 相似文献
800.
E. N. Bogomolov S. M. Piotukh I. A. Simonov V. A. Uglov 《Russian Aeronautics (Iz VUZ)》2010,53(4):416-420
A method for calculating the flowrate of the gas flowing through the cellular insert cells over the labyrinth seal strip is
proposed. The gas density is taken to be average with respect to the decisive section. It is assumed that jets flowing out
of cells disrupt the direct flow of the labyrinth seal. A practical implementation of the method is confirmed by the known
experimental data. 相似文献