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11.
Presented paper describes the basic principles and features of the implementation of a robotic network of optical telescopes MASTER, designed to study the prompt (simultaneous with gamma radiation) optical emission of gamma-ray bursts and to perform the sky survey to detect unknown objects and transient phenomena. With joint efforts of Sternberg astronomical institute, High altitude astronomical station of the Pulkovo observatory, Ural state university, Irkutsk state university, Blagoveshchensk pedagogical university, the robotic telescopes MASTER?II near Kislovodsk, Yekaterinburg, Irkutsk and Blagoveshchensk were installed and tested. The network spread over the longitudes is greater than 6?h. A further expansion of the network is considered.  相似文献   
12.
Aerosol optical properties have been studied for spring seasons when increased values of PM10 are registered. Measurements of aerosol optical properties were taken by collocated lidar and sun-photometers at Belsk, Poland, and Minsk, Belarus. A significant increase of registered aerosol optical thickness (AOT) was found during episodes with elevated PM10 concentrations. An increase of AOT at 1020 nm amounted to 50% in the case of Minsk and 18% in the case of Belsk, while an increase of AOT at 400 nm was 66% and 33%, respectively. We noted an increase of Ångström exponent by 6% at both stations and no significant increase of single scattering albedo. The LIDAR measurements together with NAAPS model results and backtrajectory analysis suggest that both the biomass burning products and the Saharan dust are responsible for increased PM10 concentrations and large AOT values during spring time. The smoke aerosol is transported over Central Europe mainly in the boundary layer, increasing both PM10 concentration and AOT. The dust aerosol transported in the free troposphere slightly affects the AOT values only. Statistically significant correlation between PM10 concentration and AOT was found during reporting period.  相似文献   
13.
The present study deals with the application of the hierarchical cluster analysis and non‐parametric tests in order to interpret the Gdańsk Beltway impact range. The data set represents concentration values for major inorganic ions (Na+, NH, K+, Mg2+, Ca2+, F, Cl, NO, and SO) as well as electrolytic conductivity and pH measured in various water samples [precipitation, throughfall water, road runoff, and surface water (drainage ditches, surface water reservoirs, and spring water)] collected in the vicinity of the beltway. Several similarity groups were discovered both in the objects and in the variables modes according to the water sample. In the majority of cases clear anthropogenic (fertilizers usage and transport, road salting in winter) and semi‐natural (sea salt aerosols, erosion of construction materials) impacts were discovered. Spatial variation was discovered for road runoff samples and samples collected from surface water reservoirs and springs. Surprisingly no clear seasonal variability was discovered for precipitation chemistry, while some evidences for existing of summer and winter specific chemical profile was discovered for road runoff samples. In general, limited range of the Gdańsk Beltway impact was proven.  相似文献   
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15.
Five seismic events occurred between August 1979 and May 1980 in the Belchatow trench area in central Poland, where large brown-coal deposits have been surface-mined since 1976. The three largest shocks had a local magnitudeML = 3.5 , seismic momentMo = 1.5 · 1014 N-m and source radiusr = 350m , approximately. The tremors had maximum intensity between 5 and 6, and from the magnitude—intensity—depth relation, the focal depth was estimated to be between 1 and 5 km.

The Belchatow tremors are the manifestation of an unusual type of induced seismicity, i.e., seismicity connected with surface mining. The removal of overburden and extensive ground-water withdrawal by the mining operations seem to be direct factors responsible for stress concentration, although preexisting tectonic stress might be the most important indirect factor responsible for the origin of these events.  相似文献   

16.
Summary The amplitude-distance curves of P waves, valid for the region of Central Asia, were derived in the distance range between 13° and 36° using observations of a network of eight Caucasian seismic stations. The curves are characterized by an anomalous increase of amplitudes between 13° and 20° followed by a large decrease of amplitudes in the distance range between 20° and 35°. Both the increase and decrease of amplitudes are interrupted by several local maxima. A comparison of the present amplitude curves with those derived for the regions of South-Eastern Europe and Asia Minor enabled us to correlate the individual local maxima of amplitude curves and to investigate the variation of their position due to the lateral inhomogeneity of the upper mantle structure in Eurasia.A. Tskhakaya deceased in 1970.  相似文献   
17.
Summary The isoseismal map of the North-Italian earthquake of 6 May 1976 was compiled using the contributions of the European countries lying within the shaken area. The characteristic feature of the macroseismic field is discussed.  相似文献   
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19.
Brückl  E.  Bodoky  T.  Hegedüs  E.  Hrubcová  P.  Gosar  A.  Grad  M.  Guterch  A.  Hajnal  Z.  Keller  G.R.  Špičák  A.  Sumanovac  F.  Thybo  H.  Weber  F. 《Studia Geophysica et Geodaetica》2003,47(3):671-679
Studia Geophysica et Geodaetica -  相似文献   
20.
Guterch  A.  Grad  M.  Keller  G.R.  Posgay  K.  Vozár  J.  Špičák  A.  Brückl  E.  Hajnal  Z.  Thybo  H.  Selvi  O. 《Studia Geophysica et Geodaetica》2003,47(3):659-669
Studia Geophysica et Geodaetica -  相似文献   
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