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Fault network of the Upper Silesian Coal Basin (USCB) is built of sets of strike-slip, oblique-slip and dip-slip faults. It is a typical product of force couple which acts evenly with the parallel of latitude, causing horizontal and anti-clockwise movement of rock-mass. Earlier research of focal mechanisms of mine tremors, using a standard fault plane solution, has shown that some events are related to tectonic directions in main structural units of the USCB. An attempt was undertaken to analyze the records of mine tremors from the period 1992–1994 in the selected coal fields. The digital records of about 200 mine tremors with energy larger than 1×104 J (M
L
>1.23) were analyzed with SMT software for seismic moment tensor inversion. The decomposition of seismic moment tensor of mine tremors was segmented into isotropic (I) part, compensated linear vector dipole (CLVD) part and double-couple (DC) part. The DC part is prevalent (up to 70%) in the majority of quakes from the central region of the USCB. A group of mine tremors with large I element (up to 50%) can also be observed. The spatial orientation of the fault and auxiliary planes were obtained from the computations for the seismic moment DC part. Study of the DC part of the seismic moment tensor made it possible for us to separate the group of events which might be acknowledged to have their origin in unstable energy release on surfaces of faults forming a regional structural pattern. The possible influence of the Cainozoic tectonic history of the USCB on the recent shape of stress field is discussed. 相似文献
2.
M. Mikolajewski C. Galan K. Gazeas P. Niarchos S. Zola M. Kurpinska-Winiarska M. Winiarski A. Majewska M. Siwak M. Drahus W. Waniak A. Pigulski G. Michalska Z. Kolaczkowski T. Tomov M. Gromadzki D. Graczyk J. Osiwala A. Majcher M. Hajduk M. Cikala A. Zajczyk D. Kolev D. Dimitrov E. Semkov B. Bilkina A. Dapergolas L. Bellas-Velidis B. Csak B. Gere P. Nemeth G. Apostolovska 《Astrophysics and Space Science》2005,296(1-4):445-449
We report multicolour photometric observations of the 2003 eclipse of the long-period (5.6 yr) eclipsing binary EE Cep. Measurements
were obtained with ten telescopes at eight observatories in four countries. In most cases, UBV(RI)C broad band filters have been used. The light curve shape shows that the obscuring body is an almost dark disk around a low-luminosity
central object. However, variations of the colour indices during the eclipse indicate that the obscuring body emits a considerable
amount of radiation in the near infrared. 相似文献
3.
The article presents results of CCD photometry in R-band of a dynamically new Comet C/2001 K5 (LINEAR), obtained at a heliocentric distance of about 5.6 AU, after the perihelion passage. Being so distant from the Sun, this comet was extremely active (Afρ close to 2000 cm), exhibiting quite well developed dust coma and tail. During the observations, general photometric behavior of the comet with heliocentric distance r was well described by the 2.5nlog(r) function with coefficient n=5. The radial profiles of the coma were found to be undulated, with mean slope of the dependence between cometary magnitude and 2.5log of aperture radius (at comet distance) equal to . The light curve of Comet LINEAR exhibited short-term variability which we attributed to cyclic changes of dust emission, induced by nucleus rotation. Model computations by some authors have revealed that active comets can change their spin status quite substantially even during a single orbital revolution. Thus, attempting to search for a rotation frequency, we have modified the classical PDM approach by including the spin acceleration term. Such DynamicalPDM (DPDM) method revealed the most reliable solution for the frequency f0=0.019048±0.000013 h−1 and its first time-derivative (index “zero” denotes reference to the mid time of the whole observing run), indicating a rapid spin-down of the nucleus. These parameters are equivalent to the rotation period of 52.499±0.036 h and its relative increment of 0.02729±0.00013. We present the most probable evolution of the rotation frequency of Comet LINEAR, based on the results of periodicity analysis and a simple, almost parameter independent, dynamical model of nucleus rotation. It is also shown that the DPDM may be an effective tool for determination of a nucleus radius, which provided us with the value of 1.53±0.25 km for Comet LINEAR. 相似文献
4.
Wacław Waniak 《Experimental Astronomy》2006,21(3):151-168
A feed-forward artificial neural network has been implemented to the problem of removing cosmic-ray hits (CRH) from CCD images.
The results of a number of tests demonstrate the effectiveness of this method especially for undersampled stellar profiles.
The problem of optimal and low price preparing of training data, which could enable real-time or at least fast post-processing
filtering out of CRH is discussed. The training and test ensembles were composed of a number of synthetic stellar profiles
involving different S/N ratios and CRH images taken from real data. Certain aspects of the network’s architecture and its
training efficiency for different modes of the back-propagation procedure as well as for the pre-process normalization of
data have been examined. It is shown that for training set composed of stellar images and CRH at a ratio of 1:2 recognition
can reach 99% in the case of stars and 96% for CRH. To determine the extent to which the cognition power of a network trained
using an ensemble of circular symmetric stellar profiles of a given radius can be generalised the test data included stellar
profiles of different radii, as well as elongated profiles. The goal was to mimic temporal changes in seeing as well as such
problems as image defocusing, the lack of isoplanatism and improper sideral tracking of a telescope. The experiments provided
us with the conclusion that for S/N > 10 excellent classification property is maintained in cases where the change in the
radius of a circular profile is up to 30%, as well as for elongated profiles where the longest dimension is almost double
that of the shortest one. Moreover, the generalization capability has been investigated for test images of synthetic pairs
of overlapping stars with different distances between components. Almost 99% recognition efficiency was achieved even if the
separation was nearly three times the radius of the stellar profile, a case when two stars could be analyzed by appropriate
software as separate objects. The example of removal of CRH from real CCD images is presented to give an idea of how an algorithm
based on a neural network can work in practice. The result of such an experiment appears fully consistent with the conclusions
drawn from the tests made on synthetic data. 相似文献
5.
W. Waniak G. Borisov M. Drahus T. Bonev K. Czart M. Küppers 《Earth, Moon, and Planets》2009,105(2-4):327-342
We present preliminary results of the narrow-band CN observations of comet 8P/Tuttle from early January 2008, realized as part of a project consisting of near-simultaneous spectroscopic monitoring of HCN at millimeter-wavelengths and optical imaging of the coma. The mean-image subtraction method revealed low-contrast CN envelopes. Using the image cross-correlation technique we measured the projected velocity of these shells. For the sunward part we found it to be equal to 0.96 ± 0.03 km s?1 on January 4 and 1.10 ± 0.01 km s?1 on January 9, whereas the anti-sunward part reached 0.73 ± 0.05 and 0.80 ± 0.02 km s?1, respectively. The periodicity of gas emission was investigated using a repeatability of the shells, their kinematics, and an aperture photometry of the near nucleus region. We found a period of 5.70 ± 0.07 h (along with multiples), consistent with previous findings by other authors. A toy Monte Carlo model was implemented to reproduce the time-series of the CN images. We show that emission of HCN into a relatively wide cone by a single active region on a rotating nucleus is the most probable scenario. 相似文献
6.
David Gubbins Peter Molnar J. G. Olliver Petr Vanīček Kenji Satake Allan M. Rubin Waclaw M. Zuberek Janusz Niewiadomski Leszek Czechowski David J. Steveson Jacek Leliwa-Kopystyński Yu. N. Korenkov Fred Lipschultz Marek Jerczyński Krzysztof E. Haman Jerzy Radziwill Maciej Sadowski Maciej Sadowski 《Pure and Applied Geophysics》1990,132(3):599-637
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Michal Siwak Stanislaw Zola Tomasz Szymanski Maria Kurpinska-Winiarska Maciej Winiarski Dorota Koziel-Wierzbowska Waclaw Waniak Michal Drahus 《New Astronomy》2012,17(8):691-696
We have analysed the available spectra of WW And and for the first time obtained a reasonably well defined radial velocity curve of the primary star. Combined with the available radial velocity curve of the secondary component, these data led to the first determination of the spectroscopic mass ratio of the system at qspec = 0.16 ± 0.03. We also determined the radius of the accretion disc from analysis of the double-peaked Hα emission lines. Our new, high-precision, Johnson VRI and the previously-available Strömgren vby light curves were modelled with stellar and accretion disc models. A consistent model for WW And – a semidetached system harbouring an accretion disc which is optically thick in its inner region, but optically thin in the outer parts – agrees well with both spectroscopic and photometric data. 相似文献
8.
Yu. N. Korenkov Carl W. Cable Vernon F. Cormier Vassily Levin Jacek A. Majorowicz Yehuda Bock Waclaw M. Zuberek Teng-fong Wong William L. Power Gary A. Robbins Piotr Raczka Krzysztof E. Haman Katarzyna Chałasinska-Macukow Ryszard Balcer Henryk Piwkowski 《Pure and Applied Geophysics》1991,137(3):309-336
9.
The results of the photoelectric photometry with the narrowband CN, C3, C2 and Blue Continuum (BC) IHW interference filters are presented. Observations were carried out with a set of diaphragms of different effective radii. On the base of the Haser model the production rates of the radicals have been obtained. The CN and C2 molecules scale lengths (3.4 × 105 km and 8.5 × 104 km respectively for 1.0 AU heliocentric distance) have been also derived. The dust continuum spectrum is negligibly low in comparison with the molecular one, which stay in agreement with the results of other observations of comet Okazaki-Levy-Rudenko. 相似文献
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