Informacja

Drogi użytkowniku, aplikacja do prawidłowego działania wymaga obsługi JavaScript. Proszę włącz obsługę JavaScript w Twojej przeglądarce.

Wyszukujesz frazę "Zachariasz, R." wg kryterium: Autor


Wyświetlanie 1-9 z 9
Tytuł:
Transparent PLZT ceramics and their practical use
Autorzy:
Zachariasz, R.
Czerwiec, M.
Ilczuk, J.
Powiązania:
https://bibliotekanauki.pl/articles/332634.pdf
Data publikacji:
2005
Wydawca:
Polskie Towarzystwo Akustyczne
Opis:
Piezoelectric ceramics lead zirconate titanate (PZT) is a material of high technological importance due to its applications in solid-state actuators, transducers and sensors. La+3 ion can be substituted for Pb+2 ion in PZT system (as called PLZT) because of its similar ionic sizes. This paper summarizes properties of transparent PLZT ceramics and their practical use.
Źródło:
Hydroacoustics; 2005, 8; 247-254
1642-1817
Pojawia się w:
Hydroacoustics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Stability of mechanical and dielectric parameters in pzt based ceramics
Autorzy:
Ilczuk, J.
Bluszcz, J.
Zachariasz, R.
Powiązania:
https://bibliotekanauki.pl/articles/332039.pdf
Data publikacji:
2004
Wydawca:
Polskie Towarzystwo Akustyczne
Opis:
The (Pb0.9Ba0.1)(Zr0.53Ti0.47)O3 + 2% mol. Nb2O5 ceramics were prepared from high purity synthesized ceramic powders by a classical sintering method. Internal friction Q-1 and Young’s modulus E were measured as a function of temperature for the sample in the initial state and after ă irradiation 5 R dose. Two internal friction peaks P1 and P2, related to oxygen vacancies and domain walls, respectively, were observed in all measurements. In addition, a minimum in modulus E associated with a phase transition internal friction peak P3 appearing at curie temperature was observed. The internal friction results indicate the changes of concentration of oxygen vacancies and the domain structure, which will be helpful in the utilities of the PZT ceramics in transducers, ultrasonic generators, wave filters, etc.
Źródło:
Hydroacoustics; 2004, 7; 69-78
1642-1817
Pojawia się w:
Hydroacoustics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Ferroelectric and ferroelectromagnetic ceramics in a view of possibilities to be used in electroacoustic
Autorzy:
Czerwiec, M.
Zachariasz, R.
Brzezińska, D.
Ilczuk, J.
Powiązania:
https://bibliotekanauki.pl/articles/331509.pdf
Data publikacji:
2008
Wydawca:
Polskie Towarzystwo Akustyczne
Tematy:
ferroelectricity
ferroelectromagnetic ceramics
piezoelectric transducers
Opis:
Ferroelectric ceramics were born in the early 1940's with the discovery of the phenomenon of ferroelectricity as the source of the unusually high dielectric constant in ceramic barium titanate capacitors. Since that time, they have been the heart and soul several multibillion dollar industries, ranging from high-dielectric-constant capacitors to later developments in piezoelectric transducers, positive temperature coefficient devices, and electrooptic light valves. Various ceramic formulations, their form, fabrications, functions, and future are described in relation to their ferroelectric nature and specific areas of applications. This paper is intended to illustrate practical uses of ferroelectric and ferroelectromagnetic ceramics obtained and investigated by the authors.
Źródło:
Hydroacoustics; 2008, 11; 63-70
1642-1817
Pojawia się w:
Hydroacoustics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Code signals transmission using MFSK modulation in shallow waters
Autorzy:
Zachariasz, K.
Schmidt, J.
Salamon, R.
Powiązania:
https://bibliotekanauki.pl/articles/332705.pdf
Data publikacji:
2001
Wydawca:
Polskie Towarzystwo Akustyczne
Opis:
The paper presents an acoustic system for the transmission of digital data in shallow coastal waters of which multi-path propagation and intense reverberations are characteristic. To ensure a small error probability of moderate speed transmission, the system uses corrective codes and a technique of incoherent modulation MFSK (Mufti Frequency Shift Keying). To synthesise the transmission signal, estimate the spectrum of the signal received and code and decode the channels, a DSP processor was used. The paper includes the results of a computer simulation in which the system was put to work in the presence of Gaussian noise. The system was tested in shallow coastal waters and the results are discussed in the paper.
Źródło:
Hydroacoustics; 2001, 4; 261-264
1642-1817
Pojawia się w:
Hydroacoustics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Underwater communication system for shallow water using modified MFSK modulation
Autorzy:
Schmidt, J.
Zachariasz, K.
Salamon, R.
Powiązania:
https://bibliotekanauki.pl/articles/332663.pdf
Data publikacji:
2005
Wydawca:
Polskie Towarzystwo Akustyczne
Opis:
The paper describes the design and operation of the Modified MFSK system for underwater communication. Its function is to transmit data and commands from ships to underwater objects in shallow coastal waters and lakes. The system was primarily required to ensure energy efficiency in its underwater section and the minimum of transmission errors. The emphasis was on non-linear distortions produced in piezoelectric transducers, an untypical source of errors.
Źródło:
Hydroacoustics; 2005, 8; 179-184
1642-1817
Pojawia się w:
Hydroacoustics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Doppler effect in the cw fm sonar
Autorzy:
Marszal, J.
Salamon, R.
Zachariasz, K.
Schmidt, A.
Powiązania:
https://bibliotekanauki.pl/articles/331758.pdf
Data publikacji:
2011
Wydawca:
Polskie Towarzystwo Akustyczne
Opis:
When sonars are used for military purposes they have to ensure unobtrusive operation, afeature that can be potentially secured by ‘silent sonars’ or continuous wave frequency modulation sonars (CW FM sonars). The article presents how these sonars operate and identifies the relations between their parameters. The Doppler effect and its impact on the CW FM sonar are studied to identify how it affects the sonar’s parameters. The results of simplified theoretical calculations are supported with results of computer simulations of a more realistic model.
Źródło:
Hydroacoustics; 2011, 14; 157-164
1642-1817
Pojawia się w:
Hydroacoustics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Method for improving multibeam sonar bearing accuracy
Autorzy:
Leśniak, W.
Marszal, J.
Salamon, R.
Zachariasz, K.
Schmidt, J.
Powiązania:
https://bibliotekanauki.pl/articles/332790.pdf
Data publikacji:
2009
Wydawca:
Polskie Towarzystwo Akustyczne
Tematy:
multibeam sonar
sonar bearing accuracy
sonars
Opis:
The paper presents a simple method for improving multibeam sonar bearing accuracy. The principle proposed here is similar to the monopulse method, a solution commonly used in radars and sonars. With no manual or automatic beam rotation, the method offers a substantial reduction in the demand for sonar computational effort. It significantly reduces bearing error for a relatively high signal to noise ratio. The paper gives a boundary value of the output signal to noise ratio which when exceeded satisfactorily improves bearing accuracy.
Źródło:
Hydroacoustics; 2009, 12; 98-108
1642-1817
Pojawia się w:
Hydroacoustics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Multibeam sonar with hexagonal array
Autorzy:
Salamon, R.
Marszal, J.
Kilian, L.
Jedel, A.
Ostrowski, Z.
Raganowicz, A.
Rudnicki, M.
Wofan, Z.
Zachariasz, K.
Powiązania:
https://bibliotekanauki.pl/articles/332250.pdf
Data publikacji:
1999
Wydawca:
Polskie Towarzystwo Akustyczne
Opis:
The paper presents a multi-beam digital sonar that was designed for monitoring and fish stock assessment in in/and waters. The sonar can also be used as a bottom profiler in lakes, rivers and shallow sea areas. The hexagonal piezoelectric transducer array co-operates with a commutator set. The 32 -channel digital beamformer creates 30 narrow receiving beams in every 60o sector of simultaneous observation. The six sectors cover the whole 360o angle range of the sonar. The beamformer digital signal processing is based on second order sampling of echo signals and the phase-shifting principle of beam deflection. The sonar block diagram, beamformer algorithms, as well as transducers designs are discussed.
Źródło:
Hydroacoustics; 1999, 2; 133-138
1642-1817
Pojawia się w:
Hydroacoustics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Modernization of ASW sonar SQS-56 at Gdansk University of Technology
Autorzy:
Marszal, J.
Schmidt, J.
Salamon, R.
Kilian, L.
Raganowicz, A.
Zachariasz, K.
Ostrowski, Z.
Jedel, A.
Rudnicki, M.
Sidorko, T.
Powiązania:
https://bibliotekanauki.pl/articles/331991.pdf
Data publikacji:
2010
Wydawca:
Polskie Towarzystwo Akustyczne
Opis:
The fast development of electronic technology and digital signal processing methods makes electronic devices, including sonar systems ones, obsolete very quickly. On the other hand the ships mechanical components including mechanical parts of sonars are operational for a few dozens of years. It makes good opportunity to modernize these devices by using modern electronic devices and new digital signal processing methods with application of existing antenna and mechanical systems. The paper presents the modernization of ASW sonar SQS-56 on the Polish frigate ORP “Kościusko”. The aim of modernization, the new parameters of the sonar and block diagram after modernization are presented.
Źródło:
Hydroacoustics; 2010, 13; 191-196
1642-1817
Pojawia się w:
Hydroacoustics
Dostawca treści:
Biblioteka Nauki
Artykuł
    Wyświetlanie 1-9 z 9

    Ta witryna wykorzystuje pliki cookies do przechowywania informacji na Twoim komputerze. Pliki cookies stosujemy w celu świadczenia usług na najwyższym poziomie, w tym w sposób dostosowany do indywidualnych potrzeb. Korzystanie z witryny bez zmiany ustawień dotyczących cookies oznacza, że będą one zamieszczane w Twoim komputerze. W każdym momencie możesz dokonać zmiany ustawień dotyczących cookies