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Abstract

Professor Aleksander Opilski has passed away on 20 April 2012. Aleksander Opilski was born on 31 August 1931 in Zagórze in the then Śląskie Voivodship. He underwent his 1st level studies in the years 1950–1953 at the Faculty of Mathematics, Physics and Chemistry of the Jagiellonian University in Krakow. His 2nd level academic education was completed at the Adam Mickiewicz University in Poznań from which he graduated in 1958 as a Master of Science in Physics.
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Abstract

Research in termoacoustics began with the observation of the heat transfer between gas and solids. Using this interaction the intense sound wave could be applied to create engines and heat pumps. The most important part of thermoacoustic devices is a regenerator, where press of conversion of sound energy into thermal or vice versa takes place. In a heat pump the acoustic wave produces the temperature difference at the two ends of the regenerator. The aim of the paper is to find the influence of the material used for the construction of a regenerator on the properties of a thermoacoustic heat pump. Modern technologies allow us to create new materials with physical properties necessary to increase the temperature gradient on the heat exchangers. The aim of this paper is to create a regenerator which strongly improves the efficiency of the heat pump.Polish acoustical community mourns the loss of Professor Marian Urbańczyk who passed away on July 10, 2013. Professor Marian Urbańczyk was born on February 2nd, 1948, in Katowice (Poland). There he attended the Silesian Technical College (Śląskie Techniczne Zakłady Naukowe), where he was a student of the electrical engineering and electronics class and in 1967 completed his secondary education with school-leaving examination and a honorary mention. In 1973, he graduated successfully (again with distinction) from the Faculty of Electrical Engineering at the Silesian University of Technology (Politechnika Śląska) in Gliwice. The same year he has joined the SUT’s Institute of Physics as a university teacher at the newly created Faculty of Mathematics and Physics. The late Professor Urbańczyk remained connected with the Institute until 2009, from 2007 to 2009 performing the function of its Deputy Director for Students’ Affairs. The scope of the Professor’s scientific interest comprised electronics of solid state, metrology, and technical physics, with special attention paid by him to acoustics, including acoustoelectronic systems and their applications in technology and metrology. In 1981, Marian Urbańczyk delivered his doctor’s dissertation concerning technical acoustics at the Institute of Fundamental Problems of Technology Polish Academy of Sciences (IPPT PAN) in Warsaw. In the year 1999, he was granted the post-doctoral degree (habilitation) by the Council of the Faculty of Electronics at the Wrocław University of Technology. In 2012, Marian Urbańczyk was made full professor by the President of Poland. The Silesian University of Technology in Gliwice remained the scene of Professor Urbańczyk’s scientific activity to the very end of his life. Since September 1, 2009, Professor had been working at the Department of Optoelectronics at the SUT’s Faculty of Electrical Engineering, acting as its Deputy Director. Professor Marian Urbańczyk was a promoter of several doctor’s dissertations and numerous master theses. In the framework of his didactic work, he has organized many students’ laboratories and workshops. He was also the author of a wide variety of teaching curriculums (syllabuses). The late Professor Urbańczyk was highly valued both by his students and coworkers. Professor Marian Urbańczyk was an unquestionable authority in the field of technical acoustics, metrology, and electronics, and an internationally acknowledged author (and co-author) of more than 200 scientific publications, nearly 50 of them having been included in the ISI list. His papers were published in highly-ranked journals and frequently cited by other authors. He was also the co-author of numerous patents and patent applications. The Professor was a member of Scientific Committees of many conferences, both domestic and international. Professor Marian Urbańczyk was a member of many international and Polish scientific societies, including the European Acoustical Association (EAA), the International Optical Engineering Society (SPIE), the Polish Acoustical Society (PTA), the Photonic Society of Poland, the Polish Physical Association (PTF), and the Polish Association of Sensor Technology (PTTS). Since 1975, Professor Urbańczyk was a member of the Polish Acoustical Society (PTA), elected later the Member of the Main Board of this organization and the Chairman (Local President) of the Board of Upper Silesia Branch of the PTA. The Professor acted also as a co-organizer of annual international conferences, including the Winter School on Wave and Quantum Acoustics and the Workshop on Acoustoelectronics. For his scientific achievements, Professor Urbańczyk has been awarded state orders, medals, and scientific rewards. Professor Urbańczyk’s death is an irreparable loss to the Silesian University of Technology, the Polish Acoustical Society, and the whole Polish scientific community. Professor Marian Urbańczyk was an extraordinary person, always very kind-hearted and understanding for others. For those who knew him personally, he was a Friend and a Master. And as the Friend and the Master we will retain him in our fond memory.
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Abstract

Nowadays the “gold clinical standard” of hemodynamics diagnostic and cardiac output measurements is pulmonary artery catheterization by means of the Swan-Ganz catheter and thermodilution. The method itself is sensitive to numerous disturbances which cause inaccurate results. One of the well-known disadvantages of thermodilution is the overestimation of results at low values of cardiac output. This effect may concern the limited slew rate of the thermoelement mounted at the tip of the catheter. In this paper the relationship between the dynamic response of the thermoelement and the uncertainty of cardiac output measurements by means of thermodilution has been investigated theoretically and experimentally.
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Abstract

The paper presents the results of investigations concerning the noninvasive method of estimating the actual volume of the blood chamber of the POLVAD-EXT type ventricular assist device (VAD) during its operation. The proposed method is based on the principle of Helmholtz's acoustic resonance. Both the theory, main stages of the development of the measurement method as well as the practical implementation of the proposed method in the physical model of the POLVAD-EXT device are dealt with. The paper contains the results of static measurements by means of the proposed method (conducted at the Department of Optoelectronics, Silesian University of Technology) as well as the dynamic measurements taken at the Foundation of Cardiac Surgery Development (Zabrze, Poland) with the professional model of the human cardiovascular system. The results of these measurements prove that the proposed method allows to estimate the actual blood chamber volume with uncertainties below 10%.
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Abstract

The paper presents the results of an analysis of gaseous sensors based on a surface acoustic wave (SAW) by means of the equivalent model theory. The applied theory analyzes the response of the SAW sensor in the steady state affected by carbon monoxide (CO) in air. A thin layer of WO3 has been used as a sensor layer. The acoustical replacing impedance of the sensor layer was used, which takes into account the profile of the concentration of gas molecules in the layer. Thanks to implementing the Ingebrigtsen equation, the authors determined analytical expressions for the relative changes of the velocity of the surface acoustic wave in the steady state. The results of the analysis have shown that there is an optimum thickness of the layer of CO sensor at which the acoustoelectric effect (manifested here as a change in the acoustic wave velocity) is at its highest. The theoretical results were verified and confirmed experimentally
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Abstract

The paper presents the results of numerical analysis of the SAW gas sensor in the steady and non-steady states. The effect of SAW velocity changes vs surface electrical conductivity of the sensing layer is predicted. The conductivity of the porous sensing layer above the piezoelectric waveguide depends on the profile of the diffused gas molecule concentration inside the layer. The Knudsen’s model of gas diffusion was used. Numerical results for the effect of gas CH4 on layers: WO3, TiO2, NiO, SnO2 in the steady state and CH4 in the non-steady state in recovery step in the WO3 sensing layer have been shown. The main aim of the investigation was to study thin film interaction with target gases in the SAW sensor configuration based on simple reaction-diffusion equation. The results of the numerical analysis allow to select the sensor design conditions, including the morphology of the sensor layer, its thickness, operating temperature, and layer type. The numerical results basing on the code elaborated numerical system (written in Python language), were analysed. The theoretical results were verified and confirmed experimentally.
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Abstract

The paper presents the results of investigations concerning the application of zinc oxide - a wideband gap semiconductor in optical planar waveguide structures. ZnO is a promising semiconducting material thanks to its attractive optical properties. The investigations were focused on the determination of the technology of depositions and the annealing of ZnO layers concerning their optical properties. Special attention was paid to the determination of characteristics of the refractive index of ZnO layers and their coefficients of spectral transmission within the UV-VIS-NIR range. Besides that, also the mode characteristics and the attenuation coefficients of light in the obtained waveguide structures have been investigated. In the case of planar waveguides, in which the ZnO layers have not been annealed after their deposition, the values of the attenuation coefficient of light modes amount to a~ 30 dB/cm. The ZnO layers deposited on the heated substrate and annealed by rapid thermal annealing in an N2 and O2 atmosphere, are characterized by much lower values of the attenuation coefficients: a~ 3 dB/cm (TE0 and TM0 modes). The ZnO optical waveguides obtained according to our technology are characterized by the lowest values of the attenuation coefficients a encountered in world literature concerning the problem of optical waveguides based on ZnO. Studies have shown that ZnO layers elaborated by us can be used in integrated optic systems, waveguides, optical modulators and light sources.
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Abstract

The paper presents analyses of current research projects connected with explosive material sensors. Sensors are described assigned to X and γ radiation, optical radiation sensors, as well as detectors applied in gas chromatography, electrochemical and chemical sensors. Furthermore, neutron techniques and magnetic resonance devices were analyzed. Special attention was drawn to optoelectronic sensors of explosive devices.
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