University of West Bohemia

About: University of West Bohemia is a education organization based out in Pilsen, Czechia. It is known for research contribution in the topics: Sputter deposition & Band gap. The organization has 2587 authors who have published 7207 publications receiving 78537 citations. The organization is also known as: Západočeská Univerzita v Plzni & ZČU.

An approach to speaker identification using multiple classifiers

Abstract: The presented paper is interested in a speaker identification problem The attributes representing the voice of a particular speaker are obtained from very short segments of the speech waveform corresponding only to one pitch period of vowels The patterns formed from the samples of a pitch period waveform are either matched in the time domain by use of a nonlinear time warping method, known as dynamic time warping (DTW), or they are converted into cepstral coefficients and compared using the cepstral distance measure Since an uttered speech signal usually contains a lot of vowels the techniques using a combination both various classifiers and multiple classifier outputs are considered in the decision making process Experiments performed for a hundred speakers are described

Flexible hard Al-Si-N films for high temperature operation

Abstract: This article reports on flexible hard Al-Si-N films prepared by reactive magnetron sputtering. The structure and mechanical properties of Al-Si-N films were controlled by the content of Si in the film, partial pressure of nitrogen p N2 used in sputtering and the power delivered to the magnetron. The Al-Si-N films with a low (≤ 10 at.%) Si content and with a high (≥ 20 at.%) Si content were prepared. Correlations between the structure, microstructure, mechanical properties and their thermal stability of the Al-Si-N films are analyzed in detail. Thermal stability of Al-Si-N films was assessed by thermal annealing in air and water vapor up to annealing temperature T a = 1200 °C. It is shown that (1) the increase of Si content in the Al-Si-N film leads to the change of its crystalline structure from polycrystalline to X-ray amorphous and (2) the flexible hard Al-Si-N films with high (i) hardness H ≈ 20 GPa, (ii) ratio H/E ⁎ ≥ 0.1, and (iii) elastic recovery W e ≥ 60% exhibit enhanced resistance to cracking and (3) the thermal stability of Al-Si-N films with a high (≥ 20 at.%) Si content achieves up to T a ≈ 1200 °C in air and up to T a ≈ 800 °C in water vapor; here the effective Young's modulus E ⁎ = E / (1 − ν 2 ), E is the Young's modulus and ν is the Poisson's ratio. Conditions under which the flexible hard Al-Si-N films with enhanced resistance to cracking and high thermal stability can be prepared are described in detail.