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Alternative interpretations of grain-size data from Quaternary deposits

Several possibilities to present and to interpret the results of granulometric analyses of Quaternary fluvial, aeolian, glacial and wash-out slope deposits were investigated. Attention is paid particularly to the cumulative curves at a probability scale and the frequency curves, and it is shown how these curves can help to determine the sedimentary environment. The inclination of the cumulative curves in the part of the maximum proportion of a particular grain size appears significant. It appears possible to obtain information on the density and dynamics of the transporting medium from the course of the cumulative curves (inclination and spread of grain size).

The examination of textural parameters allows to draw regression lines characteristic of both deposits from various sedimentary environments and deposits from one single environment but with different histories as to their transport dynamics.

Abstract

Potential drop techniques are of two types: the direct current potential drop (DCPD) technique and alternating current potential drop (ACPD) technique, and both of them are used in nondestructive testing. ACPD, as a kind of valid method in sizing metal cracks, has been applied to evaluate metal structures. However, our review of most available approaches revealed that some improvements can be done in measuring depth of metal bottom crack by means of ACPD, such as accuracy and sensitivity of shallow crack. This paper studied a novel method which utilized the slope of voltage ratio-frequency curve to solve bottom crack depth by using a simple mathematic equation based on finite element analysis. It is found that voltage ratio varies linearly with frequency in the range of 5-15 Hz; this range is slightly higher than the equivalent frequency and lower than semi-permeable frequency. Simulation and experiment show that the novel method can measure the bottom crack depth accurately.

Abstract

For an effective, in determining the index „Calving Interval“ we take into consideration the two components of each interval: service period (SP) and duration of gestation (DG). In order to obtain the optimal interval between calving (365 days) the cow should become gestant at 81 days after calving, because along with 284-285 days, length of gestation, to provide 305 days for normal lactation and 60 days for the rest of the breast enough for the formation of the udder for the next lactation.

The frequency curve has a single peak, 43.5% placed around 361 days after which the frequencies fall along a period of time long enough. The probably average of „CI“ of 360 days, which corresponds to the class with highest frequency, shows that the fecundity is good and that it can provide a rest for brest for 55 days in the case of normal lactations of 305 days.

The 42 days difference between the arithmetic mean of the „CI“ (402 days ago) and the likely media (360 days) is caused by the presence of breeding disorders. The large values of the coefficient of variance is due to the very long ranges as well as very short intervals of calving interval.

Abstract

This paper examines changes in alpine vegetation over 50 years in the Western Tatras part of the Western Carpathians Mountains in Slovakia. We focus on the following most widespread vegetation types: subalpine to subnival grasslands (alliance Juncion trifidi Krajina 1933), snowbed vegetation (alliance Festucion picturatae Krajina 1933) and dwarf-shrub vegetation (alliances Loiseleurio-Vaccinion Br.-Bl. in Br.-Bl. et Jenny 1926 and Vaccinion myrtilli Krajina 1933). The historical 1971–1977 sampling dataset was re-sampled in 2016–2017 and our research is based on a comparison of 40 pairs of these relevés. Herein, we studied (i) changes in species frequencies; (ii) changes in phytodiversity and site conditions using estimates of Ellenberg’s eco-indices and (iii) comparison of historical and current relevés over time using the nonmetric multidimensional scaling gradient analysis (NMDS) ordination method. The frequency curves reveal differences; especially in the most frequent species at 37.5−80%, which reach higher values in the current data. The higher 7.5−25% value of medium-frequent species in the historical relevés indicates progressive homogenisation of the examined vegetation. In addition, the Shannon-Wiener index of individual vegetation types revealed no significant differences in diversity or average number of species. The historical relevés included 75 species while 74 were confirmed in the current data. Statistically significant differences were determined in light factor for all three vegetation groups. This was due to the retreat of some light-demanding species. While NMDS indicated changes in Festucion and Vaccinion relevés over time, the Juncion group relevés did not follow this trend, thus confirming their high stability. The observed changes between current and historical data are attributed to changes in climate and altered land use with the cessation of grazing.

. Hydromech., 58 (1), 49-63. BURLANDO, P. and ROSSO, R. (1996): Scaling and multiscaling models of depth-duration frequency curves for storm precipitation. J. Hydrol., 187, 45-64. FEH (1999): Flood Estimation Handbook, Volume 2: Rainfall frequency estimation. Institute of Hydrology GUPTA, V.K. and WAYMIRE, E. (1990): Multiscaling properties of spatial and river flow distributions. J. Geophys. Res., 95(D3), 1999-2009. LANGOUSIS, A. and VENEZIANO, D. (2007): Intensity-duration-frequency curves from scaling representations of rainfall. Water Resour. Res., 43. MENABDE, M., SEED

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