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Stratigraphic interpretation of loess in the marginal zone of the Dnieper I ice sheet and the evolution of its landscape after deglaciation (Dnieper Upland, Ukraine)

Komar M., Łanczont M., Fedorowicz S., Gozhik P., Mroczek P., Bogucki A.

Geological Quarterly

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2018

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Vol. 62, No. 3

536--552

EN

Litho-, pedo- and palynological analyses constrained by radiometric dating of two loess-palaeosol sequences, Nahirne and Velyka Andrusivka, exposed in a cliff at the eastern edge of the Dnieper Upland, Ukraine, document regional environmental changes in the western marginal zone of the Dnieper lobe. The postglacial loess sedimentation cycle was initiated during MIS 8, immediately after the ice sheet recession. On the basis of palaeorelief analysis, subsequent morphogenetic stages of the original postglacial relief, associated with the modifying and masking role of the loess, and destructive slope processes were reconstructed. Periglacial steppe with consistently present scattered trees formed the Pleistocene landscape in the Middle Dniester area during the last three glacial periods. In such an environment, the following loess beds, correlated with marine isotope stages (MIS), were deposited: Dnieper (dn) - MIS 8, Tyasmyn (ts) - MIS 6, Uday (ud) - MIS 4 and Bug (bg) - MIS 2. During the last two warm periods: Kaydaky (kd) - MIS 7 and Pryluky (pl) - MIS 5, the landscape was not fully forested. As a result, the individual palynological features of these soils show a diverse character. The TL and OSL dates form a sequence with numerous inversions that are difficult to interpret. Although these data do not significantly influence the interpretation, they show that: 1) there are loesses that undoubtedly formed after the maximum extent of the ice sheet by short-distance transport of dust material from local fresh glacial deposits and the underlying Paleogene rocks; 2) date distortions result from the activities of an exceptionally rich pedofauna that has contaminated the material not only in the soil sections of the profile but also in the adjacent loess. It is possible to delimit a few stages of pedofaunal activity in each of the soil units.

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Intrusion detection system based on neural networks

Sachenko A., Komar M.

Zeszyty Naukowe. Organizacja i Zarządzanie / Politechnika Śląska

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2014

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z. 68

377--386

EN

Designing the neural network detector of attacks using the vector quantization is considered in this paper. It's based on improved method for hierarchical classification of computer attacks and the information compression using the principal component analysis and combining the neural network detectors.

PL

W artykule zaprezentowano podejście do projektowania detektora ataków komputerowych za pomocą sieci neuronowej i kwantyzacji wektorowej. Bazuje ono na ulepszonej metodzie hierarchicznej klasyfikacji ataków komputerowych i kompresji informacji za pomocą analizy głównych składowych i łączenia sieci neuronowych detektorów.

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Stable isotope composition of carbonates in loess at the carpathian margin (SE Poland)

Łącka B., Łanczont M., Komar M., Madeyska T.

Studia Quaternaria

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2008

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Vol. 25

3-21

EN

Samples for the study were collected from, known from the literature, outcrop profiles in Zarzecze, Radymno, Dybawka, Tarnawce and Pikulice-Nehrybka, situated at the Carpathian border, in the vicinity of the Przemyśl town, close to the San River valley (SE Poland). They represent the Vistulian loess-palaeosol sequences. Carbonates occur mainly in the loesses representing OIS 2 and 3. Pollen analysis, carried out for two profiles (Tarnawce, Radymno), throws light on palaeoecological conditions of loess cover formation and transformation.Isotopic analysis of authigenic carbonates was carried out on carbonate cemented bodies dispersed throughout the loess in forms of nodule, rhizolith and rhizocretion and on bioclasts, mainly snail shells, ostracod valves, and sparse globules (probably the internal shells of the naked snails).In the successions studied, the upper Vistulian loess deposited in environment with poor vegetation, contains rhizo- liths and rhizocretions mainly, while in the middle and lower Vistulian loess with well developed soils, gley horizons, and intercalations of subaqueous sediments, remains of snail shells and ostracod valves prevail. The two main forms of carbonates differ markedly in isotopic composition from one another. These differences seem to be more important than those between samples of one form of carbonates along particular sections. That is the result of numerous factors affecting the fractionation of carbon and, in particular, oxygen stable isotopes in the environment of precipitation of authigenic calcite. The isotopic composition of carbonates cementing sediments is controlled mainly by biominerali- zation of organic matter and local climatic parameters which were rather slightly differentiated during the formation of the studied sediments. The d13C values for bioclasts vary in a broader range than for calcitic cements. Usually the snail shell carbonate is more enriched with heavier carbon isotope than that from ostracod valves, resulting from the isotopic equilibrium with precipitation and with surface waters, respectively. Basing on our study we can conclude that fluctuations of isotope composition of authigenic carbonates make it hard to apply as a paleoclimatic indicator. However, the general trend of d18O variation in analysed carbonate fractions from leoss-palaeosol sequences displays some connections with climatic fluctuations.

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Próba rekonstrukcji rzeźby terenu i środowiska z okresu funkcjonowania późnomagdaleńskiego obozowiska w Wilczycach (Wyżyna Sandomierska)

Bałaga K., Hołub B., Kusiak J., Łanczont M., Mroczek P., Zieliński P., Komar M.

Landform Analysis

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2008

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Vol. 9

269--271

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Late Pleistocene loess-paleosol and vegetation successions at tarnawce (san river valley, carpathian foothills, Poland)

Komar M., Łanczont M.

Studia Quaternaria

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2002

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Vol. 19

27--36

EN

The Tarnawce 1 profile, which occurs in the marginal eastern part of the Polish Western Carpathians, contains loesses representing three last glacial cycles. In this paper we report the results of pollen analysis of the Eemian -Early Glacial pedocomplex and of the Lower pleni-Vistulian loesses with an interstadial paleosol. The pollen spectra of 22 samples were determined. The pollen diagram was divided into 7 local pollen assemblage zones (L PAZ). Interglacial climatic optimum was recorded with the Eemian type of vegetation in the T-4 zone. The coldest conditions occurred during the accumulation of loess, which separates the interglacial and interstadial soils.

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Analiza pyłkowa górnoplejstoceńskich lessów i gleb kopalnych stanowisk Yezupil i Halyč

Komar M.

Studia Geologica Polonica

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2002

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Vol. 119

245-251