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61.
62.
Stanisław Kasperczuk 《Celestial Mechanics and Dynamical Astronomy》1995,63(3-4):245-253
The reduced Henon-Heiles system is investigated as a Hamiltonian dynamical system obtained by applying the normalization of the HamiltonianH=1/2(p
1
2
+p
2
2
+q
1
2
+q
2
2
)+1/3q
1
3
–q
1
q
2
2
to fourth-degree terms. The related equations of motion are bi-Hamiltonian and possess the Lie-Poisson structure. Each Lie-Poisson structure possesses an associated Casimir function. When reduced to level sets of these functions, the equations of motion take various symplectic forms. The various reductions give different coordinate representations of the solutions. These coordinate representations are used to seek the simplest representation of the solutions. 相似文献
63.
Witold Szczuciński Przemysław Niedzielski Lidia Kozak Marcin Frankowski Anetta Zioła Stanisław Lorenc 《Environmental Geology》2007,53(2):253-264
Study on contamination of tsunami sediments deposited on 26 December 2004 conducted shortly after the tsunami in coastal zone
of Thailand revealed elevated contents of salts in water-soluble and some heavy metals and arsenic in bioavailable fractions
(Szczuciński et al. in Env Geol 49:321–331, 2005). Few months later rainy season started and effected in total rainfall of over 3,300 mm. This paper presents results of survey
repeated 1 year after the tsunami. To assess the effects of rainy season on mobilization of previously determined potential
contaminants, the same locations were sampled again and analysed with the same methods. The tsunami deposit layer was well
preserved but in many locations the sediments were coarser than just after tsunami due to washing out of finer fractions.
The water-soluble salts contents were strongly reduced after the rainy season. However, the concentrations of acid leachable
heavy metals and metalloids were still elevated in comparison to reference sample from an area not impacted by tsunami. It
is possible that the metals and metalloids are successively moved to more bioavailable fraction from forms which were more
resistant to mobilization. 相似文献
64.
65.
66.
High energy release during seismic events induced by mining operation is one of the major dangers perturbing production in underground mines. In this work, temporal changes of seismic event parameters for one of the Rudna Mine (Poland) panels are investigated. The study aim was to find whether the temporal clustering of smaller events in different parameters can be observed before and after the high energy events (Ml?≥?3) in the mining panel. The method chosen for analysis was the study of temporal variation of fractal dimension of the seismic events parameter sets composed from: the interevent epicentral distance (dr), logarithm of seismic energy (lE), and interevent energy coefficient (dlE), which is the absolute difference between logarithms of energy of two consecutive events. Temporal variations study was performed in equivalent dimension (ED) space. The transformation of the seismic source parameters into ED space allowed to estimate and compare the temporal changes of the fractal dimension of different parameter spaces using the same method—correlation fractal dimension, and then easily compare the obtained temporal changes of fractal dimension of different parameter sets. The effect of grouping is expressed by decrease of fractal dimension, which is connected with the similarity of events parameter values. The temporal changes of the fractal dimension of seismicity before the strong induced events would indicate some initiation phase of the process leading to the high energy release. In the case of the studied Rudna Mine panel, the temporal behavior of the fractal dimension values in different parameter spaces before seismic events showed significant changes before three out of four events with CLVD dominant source mechanisms. 相似文献
67.
Stanisław Bellert 《Astrophysics and Space Science》1970,7(2):211-230
The paper is an extension of this author's hypothesis, presented inAstrophys. Space Sci.
3 (1969), 268, which explains the red shift in terms of a geometry of static space and stationary observers. The author introduces here the notions of metric with an observer, observed distance and space of observations; he considers the problem of the equivalence of stationary observers and discusses the relation between the hypothesis, the special theory of relativity and Maxwell equations. Attention is drawn to the agreement between the hypothesis and the experimental results discussed by Shamir and Fox, and those discussed by Kennedy and Thorndike. 相似文献
68.
Witold Szczuciński Przemysław Niedzielski Grzegorz Rachlewicz Tadeusz Sobczyński Anetta Zioła Artur Kowalski Stanisław Lorenc Jerzy Siepak 《Environmental Geology》2005,49(2):321-331
Tsunami sediments deposited in a coastal zone of Thailand by the 26 December 2004 tsunami wave were sampled within 50 days after the event. All surface and ground waters in tsunami- inundated zone revealed significant salinity at that time. The tsunami sediments, composed mainly of fine to medium sand, contain significantly elevated contents of salts (Na+, K+, Ca+2, Mg+2, Cl and SO
4
−2
) in water-soluble fraction, and of Cd, Cu, Zn, Pb in the bioavailable fraction and As in the exchangeable fraction in relation to the reference sample. The origin of contaminants is marine, as well as litho- and anthropogenic. The salts and Pb, Zn and Cu reveal high correlation to each other and to the mean grain size (pore size and porosity). Serious environmental hazard exists in that region because, due to gentle morphology, there is a risk of migration of the contaminants into ground waters and food chain. 相似文献