Analytical solutions for static an dynamic stability parameters (Pcr and ωn) of an axially loaded nonuniform beam resting on a two parameter foundation are obtained using the recursive differentiation method (RDM) along with automatic differentiation. The analysis includes all cases of beam end conditions and indicates that the foundation stiffness influence is noticeable on both the critical load Per and natural frequency ωn in the case of slender beams. Also, it is found that the effect of the end conditions decreases as the slenderness parameter of the beam increases. In addition, the analysis concludes that neither the critical load nor the natural frequency corresponding to the first mode is always the smallest one in the case of beams of elastic foundations. The obtained solutions are verified and used to investigate the significance of different parameters on the critical loads and natural frequencies., Obsahuje seznam literatury a názvosloví, and V názvu článku je překlep ve slově differentation - správně differentiation (= chybí druhé i)
The study concentrates on analysis of heterogeneous rock mass deformations in the final years of underground coal extraction and during the revitalisation period after the end of mining. The research has been carried out in the Walbrzych Coal Basin where underground mining ceased at the end of the 20th Century. In the paper results of initial stages of ground deformation studies on a fragment of the Walbrzych mining grounds concerning analysis of benchmark height changes in a selected levelling line has been described. The results indicate ground subsidence in the period immediately after end of coal extraction and change to a steady uplift of the ground a few years later (2000-2008). Abnormal changes of heights in tectonic fault zones have also been observed. These could be related to heterogeneous rock mass reaction during the revitalisation period., Jan Blachowski, Stefan Cacoń and Wojciech Milczarek., and Obsahuje bibliografii
GPS permanent stations KRAW, KATO and ZYWI are part of so called Active Geodetic Network which covers entire area of Upper Silesian Coal Basin (USCB) in Poland and forms precise reference frame for geodetic and geodynamic applications. Moreover the above mentioned stations belong to EUREF Permanent Network. The stations, as datum points, play important role in precise positioning and geoid determination in area of USCB. The study of the stability of these points is one of the main components in precise monitoring of ground deformation in mining areas. The analysis of stability of permanent GPS stations KRAW, KATO and ZYWI are based on the coordinate time series obtained from the EUREF weekly solutions. The relative coordinate time series of weekly solutions for the vectors KRAW - KATO, KRAW - ZYWI , KATO - ZYWI are presented. The consistency, linearity, seasonal variations and jumps in the relative coordinate time series are discussed., Władysław Góral and Jacek Kudrys., and Obsahuje bibliografii
We investigate Solutions provided by the finite-context predictive model called neural prediction machine (NPM) built on the recurrent layer of two types of recurrent neural networks (RNNs). One type is the first-order Elman’s simple recurrent network (SRN) trained for the next symbol prediction by the technique of extended Kalman filter (EKF). The other type of RNN is an interesting unsupervised counterpart to the “claissical” SRN, that is a recurrent version of the Bienenstock, Cooper, Munro (BCM) network that performs a kind of time-conditional projection pursuit. As experimental data we chose a complex symbolic sequence with both long and short memory structures. We compared the Solutions achieved by both types of the RNNs with Markov models to find out whether training can improve initial Solutions reached by random network dynamics that can be interpreted as an iterated function system (IFS). The results of our simulations indicate that SRN trained by EKF achieves better next symbol prediction than its unsupervised counterpart. Recurrent BCM network can provide only the Markovian solution that is not able to cover long memory structures in sequence and thus beat SRN.
This paper presents some structural properties of a generalized Petri net (PN) with an algorithm to determine the (partial) conservativeness and (partial) consistency of the net. A product incidence matrix A=CCT or A~=CTC is defined and used to further improve the relations among PNs, linear inequalities and matrix analysis. Thus, based on Cramer's Rule, a new approach for the study of the solution of a linear system is given in terms of certain sub-determinants of the coefficient matrix and an efficient algorithm is proposed to compute these sub-determinants. The paper extends the common necessary and/or sufficient conditions for conservativeness and consistency in previous papers and some examples are designed to explain the conclusions finally.
Toxoplasma gondii (Nicolle et Manceaux, 1908) is an obligate intracellular apicomplexan parasite and can infect warmblooded animals and humans all over the world. Development of effective vaccines is considered the only ideal way to control infection with T. gondii. However, only one live vaccine is commercially available for use in sheep and goats. Thus more effective antigenic proteins are searched for. In the present study we report a novel protein by secreted T. gondii termed Myc regulation 1 (MYR1). The physical and chemical characteristics, epitopes, hydrophilicity and functional sites of MYR1 were analysed by multiple bioinformatic approaches. The 3D models of MYR1 proteins were constructed and analysed. Furthermore, liner B-cell epitopes and T-cell epitopes of MYR1 protein and SAG1 were predicted. Compared to SAG1, MYR1 with good B-cell epitopes and T-cell epitopes had a potentiality to become a more successful vaccine against T. gondii. The bioinformatics analysis of MYR1 proteins could laid the foundation for further studies of its biological function experimentally and provide valuable information necessary for a better prevention and treatment of toxoplasmosis., Jian Zhou, Gang Lu, Shenyi He., and Obsahuje bibliografii
Repeated geodetic observations were applied in mining location Louky near Karviná to detect surface changes from undermining in complex geo-mechanical conditions. Analyses of the subsidence magnitude and the length and direction of horizontal displacements showed that the subsidence trough was formed unevenly not only due to the position of the exploited local longwall panels and their different size but also showed a notable effect of the dominant tectonic fault. The significantly uneven development of the subsidence trough negatively affects line constructions. Terrain deformations of the road and stream pipeline were computed and classified into the building site categories according to the Czech standard ČSN 73 0039. The course of individual deformations in the monitored locality is influenced by a complex geo-mechanical situation. While the course of the subsidence curves is continuous at the observed pipeline and the classification of individual sections into building site categories corresponds with that, the road profile points out a more complex development of surface deformations. At the end of the observed period, 5 % of the profiles’ sections fell into category III (medium intensity), 49 % into category IV (moderate intensity) and 32 % stayed in category V (very moderate intensity of mining effects).
Using GNSS method, fixed points of an observation network were repeatedly surveyed on the surface of the undermined area. Below the surface, at the depth of c. 1 km, there were four mining panels exploited subsequently. The main reaction of the surface points to the changes in the rock massif and the movement of the points were different, according to their surface position, local geo-mechanical conditions etc. This paper analyses the time-dependence of the surface points mining subsidence and horizontal movements on the progress of the exploitation., Hana Doležalová, Vlastimil Kajzar, Kamil Souček and Lubomír Staš., and Obsahuje bibliografické odkazy
The aim of this study was to determine the accuracy and precision of McMaster method with Raynaud's modification in the detection of the eggs of the nematodes Toxocara canis (Werner, 1782) and Trichuris ovis (Abildgaard, 1795) in faeces of dogs. Four variants of McMaster method were used for counting: in one grid, two grids, the whole McMaster chamber and flotation in the tube. One hundred sixty samples were prepared from dog faeces (20 repetitions for each egg quantity) containing 15, 25, 50, 100, 150, 200, 250 and 300 eggs of T. canis and T. ovis in 1 g of faeces. To compare the influence of kind of faeces on the results, samples of dog faeces were enriched at the same levels with the eggs of another nematode, Ascaris suum Goeze, 1782. In addition, 160 samples of pig faeces were prepared and enriched only with A. suum eggs in the same way. The highest limit of detection (the lowest level of eggs that were detected in at least 50% of repetitions) in all McMaster chamber variants were obtained for T. canis eggs (25-250 eggs/g faeces). In the variant with flotation in the tube, the highest limit of detection was obtained for T. ovis eggs (100 eggs/g). The best results of the limit of detection, sensitivity and the lowest coefficients of variation were obtained with the use of the whole McMaster chamber variant. There was no significant impact of properties of faeces on the obtained results. Multiplication factors for the whole chamber were calculated on the basis of the transformed equation of the regression line, illustrating the relationship between the number of detected eggs and that of the eggs added to the sample. Multiplication factors calculated for T. canis and T. ovis eggs were higher than those expected using McMaster method with Raynaud modification.