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791.
O A Gusev A I Golubev 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2001,28(4):613-615
We report the results from two years of laboratory observations of the tide-associated rhythms of activity of White Sea intertidal invertebrates, Mya arenaria (Bivalvia) and Gammarus finmarchicus (Amphipoda). The tidal associated activity of these invertebrates could not be estimate as a clear circatidal clock. Gammarus activity could be phase shifted by a 0.5 h exposure to turbulent water twice a day for 2-3 days. Mya's rhythm could be changed by a single drainage of aquariums lasting about 15 min. This kind of timing system may be a relatively primitive evolution feature. 相似文献
792.
M Casolino V Bidoli E De Grandis M P De Pascale G Furano A Morselli L Narici P Picozza E Reali R Sparvoli A Galper M Korotkov Y Ozerov A Popov G Mazzenga M Ricci G Castellini S Avdeev M Boezio W Bonvicini A Vacchi N Zampa P Spillantini P Carlson C Fuglesang 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2003,31(1):135-140
In this work we present preliminary results of nuclear composition measurements on board space station MIR obtained with SILEYE-2 particle telescope. SILEYE-2 was placed on MIR in 1997 and has been working since then. It consists of an array of 6 active silicon strip detectors which allow nuclear and energetic identification of cosmic rays in the energy range between approximately 30 and 200 MeV/n. The device is attached to an helmet and connected to an eye mask which shields the cosmonaut eyes from light and allow studies of the Light Flashes (LF) phenomenon. In addition to the study of the causes of LF, the device is used to perform real time long term radiation environment monitoring inside the MIR, performing measurements in solar quiet and active days. 相似文献
793.
H.S. Sawant J.A.C.F. Neri F.C.R. Fernandes J.R. Cecatto M.R. Sankararaman C. Faria S. Stephany R.R. Rosa M.C. Andrade E.M.B. Alonso E. Lüdke K.R. Subramanian R. Ramesh M.S. Sundararajan S. Ananthakrishnan G. Swarup J.W.V. Boas L.C.L. Botti C.E. Moron J.H. Saito 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2003,32(12):2715-2720
We present the technical characteristics of a low-cost radio telescope for solar/non solar observations at decimetric (1200–1700 MHz) and centimetric (2700 and 5000 MHz) wavelengths known as Brazilian Decimetric Array (BDA). The technical specifications of the antenna, tracking system, log-periodic feed, preamplifier and the frequency-synthesised receiver with a Single Side Band (SSB) video output of 2.5 MHz are given. 相似文献
794.
795.
Based on the data obtained in simultaneous measurements on the Helios-1 and Helios-2 spacecraft, the properties of the spatial and temporal invariance of spectra of protons with energies more than 4 MeV and electrons with energies more than 0.3 MeV are studied during the phase of intensity decay in events initiated by the following associations: a flare—coronal mass ejection—coronal and interplanetary shock waves. Emphasis is placed on research into the fluxes of electrons, whose possibility to be accelerated by shock waves is problematic. It is shown that the spectra and decay times of both protons and electrons are approximately invariant relative to the flare coordinates in a wide angular range. Depending on the western or eastern spacecraft position in relation to the front part of a shock wave, one observes a delay or advance of the onset of the invariant mode relative to the shock wave arrival, which increases with the growth of the corresponding angular distance. 相似文献
796.
A.A. Arellano-Baeza R.V. García M. Trejo-Soto A. Martinez Bringas 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2009
Mexico is one of the most volcanically active regions in North America. Volcanic activity in central Mexico is associated with the subduction of the Cocos and Rivera plates beneath the North American plate. Periods of enhanced microseismic activity, associated with the volcanic activity of the Popocatépetl volcano are compared with periods, during which the microseismic activity was low. We detected systematical changes in the number of lineaments, associated with the microseismic activity due to lineament analysis of a temporal sequence of high resolution satellite images of the Popocatépetl volcano, provided by the ASTER/VNIR instrument. The Lineament Extraction and Stripes Statistic Analysis (LESSA) software package was used for the lineament extraction. In the future it would allow develop a methodology for detection of possible elevation of pressure in volcano edifice. 相似文献
797.
V.V. Grimalsky S.V. Koshevaya J.-A. Siqueiros R.-E. Perez A.N. Kotsarenko 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2009
There are a lot of objects in space associated with dusty plasma inclusions. Such inclusions may bear a prolonged shape and behave as waveguides for ion-sound waves. In the case of space plasmas, the dust particles can possess both negative charge, due to electron attachment, and positive one, due to photoionization. In this paper the propagation of linear and non-linear ion-sound wave pulses in the dusty plasma waveguides, possessing positive charge, is studied. It has been demonstrated that non-linear dynamics of baseband pulse propagation in plasma waveguide possesses essentially non-solitonic behavior. Namely, propagation of a long ion-sound pulse leads to an excitation of a shock-like wave but not a stable localized nonlinear pulse. Also, when a Korteveg–de Vries (KdV) soliton is incident onto the dusty plasma waveguide, some part of the soliton energy is captured by the waveguide and transformed into a multi-pulse structure. Additionally, an interaction of dusty plasma inclusions with KdV soliton can lead to the occurrence of transverse instabilities of the soliton and its eventual destruction. 相似文献
798.
E. Pallé P.R. Goode 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2009
The Earth’s albedo is one of the least studied fundamental climate parameters. The albedo is a bi-directional variable, and there is a high degree of anisotropy in the light reflected from a given terrestrial surface. However, simultaneously observing from all points on Earth at all reflecting angles is a practical impossibility. Therefore, all measurements from which albedo can be inferred require assumptions and/or modeling to derive a good estimate. Nowadays, albedo measurements are taken regularly either from low Earth orbit satellite platforms or from ground-based measurements of the earthshine from the dark side of the Moon. But the results from these different measurements are not in satisfactory agreement. Clearly, the availability of different albedo databases and their inter-comparisons can help to constrain the assumptions necessary to reduce the uncertainty of the albedo estimates. In recent years, there has been a renewed interest in the development of robotic and manned exploration missions to the Moon. Returning to the Moon will enable diverse exploration and scientific opportunities. Here we discuss the possibility of a lunar-based Earth radiation budget monitoring experiment, the Lunar Terrestrial Observatory, and evaluate its scientific and practical advantages compared to the other, more standard, observing platforms. We conclude that a lunar-based terrestrial observatory can enable advances in Earth sciences, complementary to the present efforts, and to our understanding of the Earth’s climate. 相似文献
799.
Lj.R. Cander B. Zolesi 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2009
In this paper, we will shortly highlight some of the aspects that COST Action 296 on Mitigation of Ionospheric Effects on Radio Systems (MIERS) and International Reference Ionosphere (IRI) have in common in an attempt to define science rationale for collaboration between these two international projects. 相似文献
800.
P.A. Bradley I. Stanislawska G. Juchnikowski 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2009
Available long-term and near-real time global and regional maps of foF2 are examined in relation to telecommunication and aeronomy requirements and recommendations are made for the best present-day maps to adopt. In particular, it is shown that current CCIR maps do not meet all requirements and should not necessarily be regarded as standards against which other mappings should be compared. 相似文献