Informacja

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

English (EN)·Polski (PL)·Yкраїнський (UK)
Przejdź do strony domowej biblioteki Centralna Biblioteka Wojskowa Link otwiera się w nowym oknie Logo biblioteki Prolib Integro - strona głównaCentralna Biblioteka Wojskowa

Wyszukujesz frazę "surface waves" wg kryterium: Temat

  Lista filtrów
Wyrównaj
    Wyświetlanie 1-6 z 6
    Tytuł:
    Rayleigh Waves in an isotropic Body with Deep Periodic Grooves
    Autorzy:
    Danicki, E.
    Powiązania:
    https://bibliotekanauki.pl/articles/178010.pdf
    Data publikacji:
    2010
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    surface acoustic waves
    Bragg reflection
    comb transducers
    Opis:
    Bragg scattering of waves propagating in a periodically disturbed substrate is widely applied in optics and micro-acoustic systems. Here, it is studied for Rayleigh waves propagating on a periodically grooved elastic substrate. Practically applied groove depth in the Bragg grating reflectors does not exceed a few percent of the Rayleigh wavelength. Here, the analysis is carried out for periodic grooves of larger depth by applying the elastic plate model for the groove walls. The computed results show that the surface wave existence and reflection depends strongly on both the groove depth and period, and that there are limited domains of both for practical applications, primarily in comb transducers of surface waves.
    Źródło:
    Archives of Acoustics; 2010, 35, 1; 67-74
    0137-5075
    Pojawia się w:
    Archives of Acoustics
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Technique for Measuring Spatial Distribution of the Surface Acoustic Wave Velocity in Metals
    Autorzy:
    Mokryy, O.
    Tsyrulnyk, O.
    Powiązania:
    https://bibliotekanauki.pl/articles/177231.pdf
    Data publikacji:
    2016
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    ultrasound
    surface acoustic waves
    acoustic wave velocity
    spatial resolution
    Opis:
    In this paper a possibility of determining a local velocity of the surface acoustic Rayleigh waves using a transducer, with the rigidly connected emitting and receiving parts, is considered. A problem on spatial resolution of such a transducer for investigation of inhomogeneous specimens is also examined. A high spatial resolution can be obtained due to the transducer displacement by a value less than the distance between the emitting and receiving parts. It is shown that in this case it is not necessary to measure the transducer displacement with a high accuracy for precise determination of the velocity. Such an effect is obtained through measuring the velocity of surface waves in one local region of the specimen with respect to the other. The criterion for optimal spatial resolution selection during spatially inhomogeneous specimens study is also proposed. The proposed criterion use is illustrated on the example of the determination of spatial distribution of the surface acoustic velocity in a steel specimen subjected to inhomogeneous plastic deformation.
    Źródło:
    Archives of Acoustics; 2016, 41, 4; 741-746
    0137-5075
    Pojawia się w:
    Archives of Acoustics
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Numerical and Experimental Analysis of the Response of a SAW Structure with WO3 Layers on Action of Carbon Monoxide
    Autorzy:
    Hejczyk, T.
    Urbańczyk, M.
    Pustelny, T.
    Jakubik, W.
    Powiązania:
    https://bibliotekanauki.pl/articles/176885.pdf
    Data publikacji:
    2015
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    gas sensor
    carbon monoxide (CO)
    piezoelectric substrate
    numerical modeling
    surface acoustic waves
    acoustoelectric effects
    Ingebrigtsen's formula
    Opis:
    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.
    Źródło:
    Archives of Acoustics; 2015, 40, 1; 19-24
    0137-5075
    Pojawia się w:
    Archives of Acoustics
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Group and Phase Velocity of Love Waves Propagating in Elastic Functionally Graded Materials
    Autorzy:
    Kiełczyński, P.
    Szalewski, M.
    Balcerzak, A.
    Wieja, K.
    Powiązania:
    https://bibliotekanauki.pl/articles/177447.pdf
    Data publikacji:
    2015
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    surface Love waves
    group velocity
    phase velocity
    functionally graded materials
    profiles of elastic constants
    direct Sturm-Liouville problem
    Opis:
    This paper presents a theoretical study of the propagation behaviour of surface Love waves in nonhomogeneous functionally graded elastic materials, which is a vital problem in acoustics. The elastic properties (shear modulus) of a semi-infinite elastic half-space vary monotonically with the depth (distance from the surface of the material). Two Love wave waveguide structures are analyzed: 1) a nonhomogeneous elastic surface layer deposited on a homogeneous elastic substrate, and 2) a semi-infinite nonhomogeneous elastic half-space. The Direct Sturm-Liouville Problem that describes the propagation of Love waves in nonhomogeneous elastic functionally graded materials is formulated and solved 1) analytically in the case of the step profile, exponential profile and 1cosh2 type profile, and 2) numerically in the case of the power type profiles (i.e. linear and quadratic), by using two numerical methods: i.e. a) Finite Difference Method, and b) Haskell-Thompson Transfer Matrix Method. The dispersion curves of phase and group velocity of surface Love waves in inhomogeneous elastic graded materials are evaluated. The integral formula for the group velocity of Love waves in nonhomogeneous elastic graded materials has been established. The results obtained in this paper can give a deeper insight into the nature of Love waves propagation in elastic nonhomogeneous functionally graded materials.
    Źródło:
    Archives of Acoustics; 2015, 40, 2; 273-281
    0137-5075
    Pojawia się w:
    Archives of Acoustics
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Surface Acoustic Wave Interaction with a Mixture of Oxygen and Nitrogen
    Autorzy:
    Pasternak, Mateusz
    Jasek, Krzysztof
    Grabka, Michał
    Borowski, Tomasz
    Powiązania:
    https://bibliotekanauki.pl/articles/176628.pdf
    Data publikacji:
    2020
    Wydawca:
    Polska Akademia Nauk. Czasopisma i Monografie PAN
    Tematy:
    surface acoustic wave sensors
    oxygen detection
    leaky Rayleigh waves
    Opis:
    Parameters of surface acoustic waves (SAW) are very sensible to change of physical conditions of a propagation medium. In the classical theory formulation, the waves are guided along the boundary of semi-infinity solid state and free space. A real situation is more complex and a medium commonly consists of two physical components: a solid substrate and a gaseous or liquid environment. In the case of stress-free substrate, the strongest impact on SAW properties have surface electrical and mechanical conditions determined by solids or liquids adhering to the boundary. This impact is utilised for constructing sensors for different gases and vapours e.g. (Jakubik et al., 2007; Hejczyk et al., 2011; Jasek et al., 2012). The influence of gaseous environment on the SAW properties is usually very weak and ignored. However, in certain condition it can be significant enough to be applied to sensor construction. In general, it concerns Rayleigh wave devices where energy leakage phenomenon is perceptible, especially when the gas being detected considerably changes the density of environment. The paper presents the results of experiments with oxygen-nitrogen mixture. Their primary aim was focused on finding the dependence of resonant frequency and attenuation in SAW resonator on parameters and concentrations of the gas in the environment.
    Źródło:
    Archives of Acoustics; 2020, 45, 3; 483-486
    0137-5075
    Pojawia się w:
    Archives of Acoustics
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    New Surface-Plasmon-Polariton-Like Acoustic Surface Waves at the Interface Between Two Semi-Infinite Media
    Autorzy:
    Kiełczyński, Piotr
    Powiązania:
    https://bibliotekanauki.pl/articles/31340115.pdf
    Data publikacji:
    2022
    Wydawca:
    Polska Akademia Nauk. Czasopisma i Monografie PAN
    Tematy:
    shear horizontal acoustic waves
    surface plasmon polaritons
    phase velocity
    group velocity
    Poynting vector
    Opis:
    This paper presents theory of new shear horizontal (SH) acoustic surface waves that propagate along the interface of two semi-infinite elastic half-spaces, one of which is a conventional elastic medium and a second one an elastic metamaterial with a negative and frequency dependent shear elastic compliance. This new surface waves have only one transverse component of mechanical displacement, which has a maximum at the interface and decays exponentially with distance from the interface. Similar features are also shown by the acoustic shear horizontal Maerfeld-Tournois surface waves propagating at the interface of two semi-infinite elastic media due to the piezoelectric effect that should occur in at least one semi-space. The proposed new shear horizontal acoustic surface waves exhibit also strong formal similarities with the electromagnetic surface waves of the surface plasmon polariton (SPP) type, propagating along a metal-dielectric planar interface. In fact, the new shear horizontal elastic surface waves possess a large number of properties that are inherent for the SPP electromagnetic surface waves, such as strong subwavelength concentration of the wave field in the proximity of the guiding interface, low phase and group velocity etc. As a result, the new shear horizontal acoustic surface waves can find applications in sensors with extremely high sensitivity, employed in measurements of various physical parameters, such as viscosity of liquids, as well as in biosensors, chemosensors, or a near field acoustic microscopy (subwavelength imaging) and miniaturized devices of microwave acoustics.
    Źródło:
    Archives of Acoustics; 2022, 47, 3; 363-371
    0137-5075
    Pojawia się w:
    Archives of Acoustics
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
      Wyświetlanie 1-6 z 6

      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