Implementation of the DSSS method in watermarking digital audio objects

The paper presents the results of implementation in the Matlab environment for watermarking embedder and extractor based on the Direct Sequence Spread Spectrum (DSSS). A block diagram of watermarking system, an analysis of watermarked signal reproduced as well as watermarking system robustness to degrading factors: lossy compression, signal-to-noise ratio (SNR) as well as a change in sampling frequency, were shown

THE MAXIMAL MUSCLE TORQUES DISTRIBUTION AMONG MUSCLE GROUPS IN ELITE ATHLETES IN COMBAT SPORTS

INTRODUCTION: The purpose of the study was to point out typical asymmetries in strength distribution among main muscle groups in top athletes representing various kinds of combat sports. The differences in strength between tested groups were also considered and discussed. METHODS: Three groups of high-level sportsmen (11 fencers, 16 judokas and 16 boxers) took part in the experiment. Maximal muscle torques were measured in isometric conditions for flexion and extension in the elbow, shoulder, knee and hip joints for the left and right extremity. Special torquemeter devices (chair and bench) were utilized for measurement. The 2-way MACNOVA for repeated measures (8 variables) was employed to test differences in average strength between sports and sides. The logarithm of the body mass was included as a covariate. The Kolmogorov-Smirnov test was used to examine the distributions of the tested variables. RESULTS AND CONCLUSIONS: Statistical analysis revealed significant differences in average strength for both analyzed factors: sports (Rao's R=7.34,), sides (Rao's R=10.66, ) and their interaction (Rao's R=1.86, ). The asymmetrical strength distribution is thought to be the result of specific training methods applied in each tested sport discipline. The tested groups differed in strength in elbow, knee and hip for both flexion and extension. No matter how the body mass influence was controlled, the strength in the group of boxers was found lower, especially for knee and hip extensions. Fig.1. Mean values of maximal muscle torques for elbow (E), arm (A), knee (K), and hip (H) flexion (F) and extension (E) estimated for the athletes representing fencing, judo and boxing

On the Resistance Evaluation of Lateral-torsional Buckling of Bisymmetrical I-section Beams Using Finite Element Simulations

AbstractEvaluation of the lateral-torsional buckling resistance of bisymmetrical I-section beams using finite element method was widely discussed in the paper. Numerous FEM simulations with regard to the stability behavior of steel structural elements subjected to bending about the major principal axis were performed. The use of different finite element modeling techniques and their influence on obtained results were presented by the authors. The ultimate state of both perfect and imperfect elements was assessed. Considerations were concerned with hot-rolled wide flange HEB and narrow flange IPE section beams. Idealization of boundary conditions of FEM models complies with the assumptions used in the analytical formulation of stability problems of thin-walled beams. Geometrically and materially nonlinear analyses GMNA and GMNIA preceded by LBA analyses were carried out. Numerical simulations were conducted with use of ABAQUS/ Standard program

Chromium distribution in shoots of macrophyte Callitriche cophocarpa Sendtn.

The aim of the study was the analysis of Cr distribution in shoots of the macrophyte Callitriche cophocarpa by means of two X-ray-based techniques: micro X-ray fluorescence (mu XRF) and electron probe X-ray microanalysis (EPXMA). Plants were treated with 100 mu M (5.2 mg l(-1)) chromium solutions for 7 days. Cr was introduced independently at two speciations as Cr(III) and Cr(VI), known for their diverse physicochemical properties and different influence on living organisms. A comparative analysis of Cr(III)-treated plants by EPXMA and mu XRF demonstrated high deposition of Cr in epidermal glands/hairs localized on leaves and stems of the plant shoots. Cr in Cr(III)-treated plants was recorded solely in glands/hairs, and the element was not present in any other structures. On the other hand, Cr in Cr(VI)-treated group of plants was rather found in vascular bundles. Moreover, the concentration of Cr in Cr(VI)-treated plants was significantly lower than in plants incubated in Cr(III) solution. The results obtained in this work suggest differences in chromium uptake, transport and accumulation dependent on the oxidative state of the element

A new method of frequency offset correction using coherent averaging, Journal of Telecommunications and Information Technology, 2005, nr 1

This paper describes a new method of frequency offset correction to improve clock stability in communication systems where the temporary drift or jitter of phase angle is not accepted. This method bases on coherent spectral averaging with a special phase scanning algorithm. Achieved results show that proposed method is effective for strongly degraded signals. Method is useful for precise phase angle reconstruction in these systems where clock stability of the transceiver and receiver is insufficient

New model of identity checking in telecommunication digital channels, Journal of Telecommunications and Information Technology, 2006, nr 3

We proposed an OFDM and watermarking based technology system for correspondent identity verification (CIVS) in military telecommunication digital channels. Correspondent personal identity signature (CPIS) is represented by digital watermark. The main idea of this system solution is to verify the end user who sends acoustic signal, e.g., speech, music, etc., via Internet, HF/UHF radio, modem, etc. OFDM modulation scheme is used to prepare secret digital signature. This signature is a single-use secret key used for correspondent verification, thus binary sequence of that key is changing for every session. We describe transmitter and receiver block scheme. The results of experiments for both ideal and degraded signals are described in details too. The results are summarized with comments and conclusion

Conservation of Primula farinosa in Poland with respect to the genetic structure of populations

The bird’s-eye primrose (Primula farinosa L.) is an endangered species in Poland. The sole remaining, and critically endangered, population of approximately 300 flowering plants is located in the Beskid Sądecki Mountains (Jaworki, Poland). The genetic investigation was performed using highly variable microsatellite markers on a total of four populations: the Polish population and its three nearest known Slovak counterparts. We hypothesize that the Polish population is a relic of the previously much wider Central European mountain/lowland range and is thus genetically distinct from the rest of the Slovak stock. Clarification of this issue is needed before active protection interventions such as artificial supplementation can be carried out. Our results, particularly those from STRUCTURE Bayesian clustering, showed clear population structure within the dataset: all three Slovak populations were dominated by one genetic group, while the Polish population comprised mostly individuals dominated by the second genetic group. Only limited gene flow was observed between the Polish and Slovak populations. This demonstrates the distinct genetic makeup of the Jaworki population, which is probably the result of prolonged isolation from the rest of the P. farinosa range and admixture of genes from various lineages. Their origin could be determined by including plant material from the rest of the P. farinosa range, i.e., Scandinavian, Baltic, and Alpine/Carpathian locations, in a future study. The immediate practical application of our results is the recommendation that all supplementation interventions to the Jaworki population must be limited to plants produced from locally collected seeds

Sand Removal from Sandstone Cliffs as the Main Factor Influencing Properties of Organic Soils – a Case Study of Transitional Bog in the Stołowe Mountains

With this paper we investigate the effect of sand contribution to organic soils and direct influence of this process on the physical and physicochemical properties on the example of transitional bog in the Stołowe Mountains (the Central Sudetes), which was periodically covered by sand material from sandstone cliffs weathering. Field survey and soil sampling were conducted in August 2015 in the area of Białe Skały. Soil material for laboratory analysis was collected from three peat cores, while soil samples were collected from each soil horizon distinguished in each core. Obtained results indicate the great impact of mineral material admixture on soil properties, both physicochemical and chemical. Recorded values of each soil parameter in the organic horizons adjacent to the mineral interlayers differ considerably from those obtained in the soil profile free of sand admixtures. Preliminary study of soil cover of transitional bog will allow correct planning of palaeoecological research about genesis and evolution of this peatland.