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431.
R.A. Howard N.R. Sheeley M.J. Koomen D.J. Michels 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》1984,4(7):307-310
The Solwind coronagraph on the P78-1 earth-orbiting satellite has been monitoring the Sun routinely at 10-minute intervals during the 5-year interval from April, 1979 to the present. In a statistical analysis of about 1000 mass ejections observed through the end of 1981, we find an average occurrence rate of 1.8 mass ejections per day. Histograms of speed, central latitude, angular span, brightness, and other parameters have been constructed, and properties such as shape classification have been tabulated. These characteristics are summarized for these years near sunspot maximum. The average speed and mass estimate are found to be similar to those found at the declining phase of the previous sunspot cycle. The angular span and central latitude distributions are quite different than seen during the declining phase, and are very dependent upon structural class. The fluctuations in the occurrence rate of CMEs does not seem to match the fluctuations in the sunspot number. There is a tendency for high speed CMEs to occur more frequently in 1981 than in 1980, and more frequently in 1980 than in 1979. 相似文献
432.
Ilyin VK Smirnov IA Soldatov PE Korniushenkova IN Grinin AS Lykov IN Safronova SA 《Acta Astronautica》2004,54(5):357-361
The waste management strategy for the future should meet the benefits of humanity safety, respect principals of planet ecology, and compatibility with other habitability systems. For these purpose the waste management technologies, relevant to application of the biodegradation properties of bacteria are of great value. The biological treatment method is based upon the biodegradation of organic substances by various microorganisms. The advantage of the biodegradation waste management in general: it allows to diminish the volume of organic wastes, the biological hazard of the wastes is controlled, and this system may be compatible with the other systems. The objectives of our study were: to evaluate effectiveness of microbial biodegradation of non-pretreated substrate, to construct phneumoautomatic digester for organic wastes biodegradation, and to study microbial characteristics of active sludge samples used as inoculi in biodegradation experiment. The technology of vegetable wastes treatment was elaborated in IBMP and BMSTU. For this purpose the special unit was created where the degradation process is activated by enforced reinvention of portions of elaborated biogas into digester. This technology allows to save energy normally used for electromechanical agitation and to create optimal environment for anaerobic bacteria growth. The investigations were performed on waste simulator, which imitates physical and chemical content of food wastes calculated basing on the data on food wastes of moderate Russian city. The volume of created experimental sample of digester is 40 l. The basic system elements of device are digesters, gas receiver, remover of drops and valve monitoring and thermal control system. In our testing we used natural food wastes to measure basic parameters and time of biodegradation process. The diminution rate of organic gained 76% from initial mass taking part within 9 days of fermentation. The biogas production achieved 46 l per 1 kg of substrate. The microbial studies of biodegradation process revealed following peculiarities: (i) gradual quantitative increasing of Lactobacillus sp. (from 10(3) to 10(5) colony forming units (CFU) per ml), (ii) activation of Clostridia sp. (from 10(2) to 10(4)CFU/ml), (iii) elimination of aerobic conventional pathogens (Enterobacteriaceae sp., Protea sp., staphylococci). The obtained results allow to evaluate effectiveness of proposed technology and to determine the leading role of lactobacilli and clostridia in process of natural wastes biodegradation. Our further investigations shall further be concentrated on creation of artificial inoculi for launching of food wastes biodegradation. These inoculi will include active and adapted strains of clostridia and lactobacilli. 相似文献
433.
Nikolai M. Gavrilov Andrey V. Koval Alexander I. Pogoreltsev Elena N. Savenkova 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2018,61(7):1819-1836
Parameterization schemes of atmospheric normal modes (NMs) and orographic gravity waves (OGWs) have been implemented into the mechanistic Middle and Upper Atmosphere Model (MUAM) simulating atmospheric general circulation. Based on the 12-members ensemble of runs with the MUAM, a composite of the stratospheric warming (SW) has been constructed using the UK Met Office data as the lower boundary conditions. The simulation results show that OGW amplitudes increase at altitudes above 30 km in the Northern Hemisphere after the SW event. At altitudes of about 50 km, OGWs have largest amplitudes over North American and European mountain systems before and during the composite SW, and over Himalayas after the SW. Simulations demonstrate substantial (up to 50–70%) variations of amplitudes of stationary planetary waves (PWs) during and after the SW in the mesosphere-lower thermosphere of the Northern Hemisphere. Westward travelling NMs have amplitude maxima not only in the Northern, but also in the Southern Hemisphere, where these modes have waveguides in the middle and upper atmosphere. Simulated variations of PW and NM amplitudes correspond to changes in the mean zonal wind, EP-fluxes and wave refractive index at different phases of the composite SW events. Inclusion of the parameterization of OGW effects leads to decreases in amplitudes (up to 15%) of almost all SPWs before and after the SW event and their increase (up to 40–60%) after the SW in the stratosphere and mesosphere at middle and high northern latitudes. It is suggested that observed changes in NM amplitudes in the Southern Hemisphere during SW could be caused by divergence of increased southward EP-flux. This EP-flux increases due to OGW drag before SW and extends into the Southern Hemisphere. 相似文献
434.
F. Dehaeze G. N. Barakos A. N. Kusyumov S. A. Kusyumov S. A. Mikhailov 《Russian Aeronautics (Iz VUZ)》2018,61(1):40-47
This paper applies the Detached-Eddy Simulation (DES) method to resolve a larger part of the flow spectrum around rotor blades in hover and forward flight. A comparison between DES and Unsteady Reynolds–Averaged Navier–Stokes simulation was carried out for the case of a forward flying rotor suggesting that DES has great potential for rotor applications. 相似文献
435.
Cosmic Research - Using the Pontryagin maximum principle and the Kustaanheimo–Stiefel variables, the spatial problem of optimal launching into a given orbit of a spacecraft (SC) controlled by... 相似文献
436.
V. A. Sadovnichii M. I. Panasyuk V. M. Lipunov A. V. Bogomolov V. V. Bogomolov G. K. Garipov E. S. Gorbovskoy D. S. Zimnukhov A. F. Iyudin M. A. Kaznacheeva V. V. Kalegaev P. A. Klimov A. S. Kovtukh V. G. Kornilov N. V. Kuznetsov I. A. Maksimov S. K. Mit V. I. Osedlo V. L. Petrov M. V. Podzolko E. P. Popova A. Yu. Poroykov I. A. Rubinstein K. Yu. Saleev S. I. Svertilov V. I. Tulupov B. A. Khrenov V. V. Chazov A. S. Chepurnov Ya. A. Shtunder A. N. Shustova I. V. Yashin 《Cosmic Research》2018,56(6):488-497
437.
Valentin A. Shuvalov Dmitry N. Lazuchenkov Nikolai B. Gorev Galina S. Kochubei 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2018,61(1):355-366
Using a cylindrical Langmuir probe and the authors’ proprietary two-channel pressure transducer, ionospheric plasma parameter distributions along the orbit of the Sich-2 satellite (Ukraine, 2011–2012) were measured. This paper is concerned with identifying the space–time location of ionospheric plasma disturbance sources, including the epicenters of actual earthquakes (before or during the satellite flyover) and incipient earthquakes on the subsatellite track, from the measured distributions of the electron density and temperature and the neutral particle temperature along the satellite orbit. To do this, the measured ionospheric plasma parameter distributions are connected to the coordinates on the subsatellite track.It is shown that local disturbances in the electron density and temperature and neutral particle temperature distributions in the satellite orbit in the ionosphere may serve as indicators of seismic activity on the subsatellite track. The epicenters of incipient earthquakes may be set off from other plasma parameter disturbance sources associated with seismic activity using information provided by special monitoring and survey centers that monitor the current seismic situation. 相似文献
438.
S.A. Demin Y.A. Nefedyev A.O. Andreev N.Y. Demina S.F. Timashev 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2018,61(2):639-644
The analysis of turbulent processes in sunspots and pores which are self-organizing long-lived magnetic structures is a complicated and not yet solved problem. The present work focuses on studying such magneto-hydrodynamic (MHD) formations on the basis of flicker-noise spectroscopy using a new method of multi-parametric analysis. The non-stationarity and cross-correlation effects taking place in solar activity dynamics are considered. The calculated maximum values of non-stationarity factor may become precursors of significant restructuring in solar magnetic activity. The introduced cross-correlation functions enable us to judge synchronization effects between the signals of various solar activity indicators registered simultaneously. 相似文献
439.
A. N. Sabirzyanov A. I. Glazunov A. N. Kirillova K. S. Titov 《Russian Aeronautics (Iz VUZ)》2018,61(2):257-264
Multiparameter studies of the discharge coefficient dependence on the nozzle geometry and the presence of a condensed phase in combustion products were performed. The simulation results obtained satisfactorily agree with the well-known generalized data. The modern computational fluid dynamics methods were shown to be able to refine the generalized empirical relations. 相似文献
440.
David P. O’Brien Andre Izidoro Seth A. Jacobson Sean N. Raymond David C. Rubie 《Space Science Reviews》2018,214(1):47
The planetary building blocks that formed in the terrestrial planet region were likely very dry, yet water is comparatively abundant on Earth. Here we review the various mechanisms proposed for the origin of water on the terrestrial planets. Various in-situ mechanisms have been suggested, which allow for the incorporation of water into the local planetesimals in the terrestrial planet region or into the planets themselves from local sources, although all of those mechanisms have difficulties. Comets have also been proposed as a source, although there may be problems fitting isotopic constraints, and the delivery efficiency is very low, such that it may be difficult to deliver even a single Earth ocean of water this way. The most promising route for water delivery is the accretion of material from beyond the snow line, similar to carbonaceous chondrites, that is scattered into the terrestrial planet region as the planets are growing. Two main scenarios are discussed in detail. First is the classical scenario in which the giant planets begin roughly in their final locations and the disk of planetesimals and embryos in the terrestrial planet region extends all the way into the outer asteroid belt region. Second is the Grand Tack scenario, where early inward and outward migration of the giant planets implants material from beyond the snow line into the asteroid belt and terrestrial planet region, where it can be accreted by the growing planets. Sufficient water is delivered to the terrestrial planets in both scenarios. While the Grand Tack scenario provides a better fit to most constraints, namely the small mass of Mars, planets may form too fast in the nominal case discussed here. This discrepancy may be reduced as a wider range of initial conditions is explored. Finally, we discuss several more recent models that may have important implications for water delivery to the terrestrial planets. 相似文献