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Plzen, Czech Republic

The University of West Bohemia is a university in Pilsen, Czech Republic. It was founded in 1991 and consists of nine faculties. Wikipedia.

Musil J.,University of West Bohemia
Surface and Coatings Technology | Year: 2012

The article reports on the enhanced hardness of nanocomposite coatings, their thermal stability, protection of the substrate against oxidation at temperatures above 1000°C, X-ray amorphous coatings thermally stable above 1000°C and new advanced hard nanocomposite coatings with enhanced toughness which exhibit (i) low values of the effective Young's modulus E satisfying the condition H/E >0.1, (ii) high elastic recovery W e≥60%, (iii) strongly improved tribological properties, and (iv) enhanced resistance to cracking; here E =E(1-ν 2), E is the Young's modulus and ν is the Poison's ratio. At the end trends of next development of hard nanocomposite coatings are briefly outlined. © 2012 Elsevier B.V.

The article deals with a method of calculation of off-axis light propagation between parallel planes using discretization of the Rayleigh-Sommerfeld integral and its implementation by fast convolution. It analyses zero-padding in case of different plane sizes. In case of memory restrictions, it suggests splitting the calculation into tiles and shows that splitting leads to a faster calculation when plane sizes are a lot different. Next, it suggests how to calculate propagation in case of different sampling rates by splitting planes into interleaved tiles and shows this to be faster than zero-padding and direct calculation. Neither the speedup nor memory-saving method decreases accuracy; the aim of the proposed method is to provide reference data that can be compared to the results of faster and less precise methods. © 2010 Optical Society of America.

Lobaz P.,University of West Bohemia
Optics Express | Year: 2013

In computational Fourier optics, computer generated holography, etc., coherent light propagation calculation between parallel planes is the essential task. A proper calculation discretization in the off-axis case leads to big memory demands in order to avoid aliasing errors. The proposed method typically cuts down the memory demands one hundred times. The principle of the method is based on the observation that there is a close correspondence between the reconstruction process (opposite of the sampling process) and prefiltering of the convolution kernel. © 2013 Optical Society of America.

Sestak J.,University of West Bohemia
Journal of Thermal Analysis and Calorimetry | Year: 2014

Physical meaning of activation energy is analyzed from the viewpoint of non-isothermal kinetic evaluation. The term of heat inertia, meaning the degree of slowness with which the temperature of a body approaches that of its surroundings, is examined, and its impact on activation energy determination is discussed, which is particularly functional for a DTA peak kinetic appraisal. Impact of a process equilibrium background on kinetics is recollected as specifically important for Kissinger kinetic evaluation distinguishing competent case of glass cold crystallization on heating but unsuitable for melt crystallization on cooling without introducing additional thermodynamic terms. Parallel to non-Arrhenian kind of kinetics, an analogous model-free description is advocated accentuating a generalized approach by logistic functions. © 2014 Akadémiai Kiadó, Budapest, Hungary.

Sestak J.,University of West Bohemia
Journal of Thermal Analysis and Calorimetry | Year: 2013

History of thermoscopy and thermometry is reviewed showing the role of temperature degrees including the forgotten logarithmic scale. The importance of natural laws of energy, motion, least action, and thermal efficiency is discussed. The meaning of idiomatic terms - thermal physics, thermodynamics, thermostatics, thermotics, and thermal analysis - is specified and revealed within two parallel developed branches of thermal science. Itemized 105 references with titles. © 2012 Akadémiai Kiadó, Budapest, Hungary.

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