Informacja

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

Wyszukujesz frazę "41.20.Jb" wg kryterium: Temat


Tytuł:
Yearly, Seasonal and Daily Variations of Radio Refractivity
Autorzy:
Žilinskas, M.
Tamošiūnas, S.
Tamošiūnaitė, M.
Tamošiūnienė, M.
Powiązania:
https://bibliotekanauki.pl/articles/1505233.pdf
Data publikacji:
2011-04
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
84.40.-x
41.20.Jb
Opis:
Yearly, seasonal and daily variations of radio refractivity have been analyzed. The method proposed in the recommendation of International Telecommunication Union ITU has been used. The local meteorological data have been used in calculation of radio refractivity. The highest values of the radio refractivity have been observed in Klaipėda (in Seacoast) in the year 2009. In July, the values of the radio refractivity were highest in all localities investigated here and over all the time of the day in the year 2009. In the continental part of Lithuania (in Vilnius and Kaunas), analysis of radio refractivity has been made by using the meteorological data of longer period (starting from April 2005 up to July 2010). Five-year meteorological data collected in February, April, July and October have been used. It was obtained that the values of refractivity in the year 2010 are much higher than ones obtained in all the years of the period investigated here.
Źródło:
Acta Physica Polonica A; 2011, 119, 4; 533-536
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Material Analysis and Application for Radio Frequency Electromagnetic Wave Shielding
Autorzy:
Yener, S.
Cerezci, O.
Powiązania:
https://bibliotekanauki.pl/articles/1187407.pdf
Data publikacji:
2016-04
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
41.20.Gz
41.20.Jb
Opis:
Our environment is full of radio frequency (RF) electromagnetic radiation due to rapid progress of wireless communication technologies, which have many applications, such as base stations of mobile communication networks and wireless internet antennas. In the context of Electromagnetic Compatibility (EMC) discipline, the word shield is used to describe any sort of metal sheet or material capable of reflecting, refracting or absorbing electromagnetic radiation (EMR), which is custom manufactured for the target electronic device casing, in a way to intervene any radiation passing to and from the device. Examining of electromagnetic shielding effectiveness (SE) is an important part of not only ensuring electromagnetic compatibility and of protecting electrical and electronic equipment but also protection of human beings against electromagnetic energy exposure as well. In this study, after a brief introduction and review on electromagnetic shielding, material selection and their applications for an indoor environment protection against electromagnetic radiation are explained. Potential electromagnetic shielding values of fabrics found in the market have been analyzed and compared by considering various criteria and requirements. Experimental results show that around 20 dB shielding effectiveness values can be obtained using test fabrics for a typical indoor environment.
Źródło:
Acta Physica Polonica A; 2016, 129, 4; 635-638
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Dispersion of Bloch Modes in a Multilayer Structure with Alternating Left-Handed and Right-Handed Materials
Autorzy:
Vukovic, S.
Aleksic, N. B.
Timotijevic, D. V.
Powiązania:
https://bibliotekanauki.pl/articles/2047883.pdf
Data publikacji:
2007-11
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
41.20.Jb
78.66.Fd
78.68.+m
Opis:
We study all-evanescent eigenmodes of a one-dimensional infinite periodic structure with alternating left-handed and right-handed materials that propagate perpendicularly to the surface or guided eigenmodes. Investigation of dispersion properties of such Bloch modes is shown to be crucial for understanding of an efficient radiation energy transport across the periodic multilayer structure. Frequency pass bands and gaps are found as a function of the two orthogonal wave vectors: the Bloch wave vector k$\text{}_{B}$ and the surface wave vector k$\text{}_{S}$. We demonstrate that pass bands of both TE- and TM-polarizations can exist and, under certain conditions, may overlap.
Źródło:
Acta Physica Polonica A; 2007, 112, 5; 1061-1066
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Negative Refraction as a Source of Some Pedagogical Problems
Autorzy:
Veselago, V.
Powiązania:
https://bibliotekanauki.pl/articles/1814051.pdf
Data publikacji:
2007-11
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
78.20.Ci
41.20.Jb
Opis:
The appearance of material with negative values of dielectric and magnetic permeabilities ε and μ and with negative index of refraction n forces to revise the accustomed forms of some well-known formulae of electrodynamics. This is connected with fact, that these correlations in repressing majority of sources is written in tacit suggestion that magnetic permeability of most of materials is μ=1, factor of refraction n=ε and is undoubtedly executed the correlation n > 0. Such approach could be named as "nonmagnetic". However, if n <0, this nonmagnetic approach can bring very hard mistakes.
Źródło:
Acta Physica Polonica A; 2007, 112, 5; 777-781
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Confined Metamaterial Structures Based on Coordinate Transformations
Autorzy:
Vasić, B.
Gajić, R.
Isić, G.
Hingerl, K.
Powiązania:
https://bibliotekanauki.pl/articles/1807844.pdf
Data publikacji:
2009-07
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
03.50.De
41.20.Jb
42.70.-a
Opis:
We apply transformation optics to structures in which the electromagnetic field is confined by highly conducting coatings. The possibility of changing the field propagation direction without perturbation is demonstrated on the example of a waveguide bend. Using this approach it is also possible to reshape a confined structure in order to meet certain external requirements and to redistribute a field in order to obtain desired field distribution. The structure implementation implies replacing a part of given confined structure with a metamaterial designed using the technique of transformation optics. Simplification of structure realization based on using reduced set of material parameters is examined. Our theoretical considerations are confirmed by full wave finite element simulations of a waveguide bend.
Źródło:
Acta Physica Polonica A; 2009, 116, 1; 96-98
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Acousto-Electromagnetic Analogies in Diffraction Phenomena Occurring in the Semi-Infinite Cylindrical Waveguide
Autorzy:
Snakowska, A.
Powiązania:
https://bibliotekanauki.pl/articles/1807756.pdf
Data publikacji:
2009-09
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
41.20.Jb
43.20.Wd
Opis:
The paper presents analogies between acoustic and electromagnetic wave field occurring in limited areas, such as waveguides, when electromagnetic waves are not purely transversal. The acousto-electromagnetic analogies exist in structures such as plane, rectangular or cylindrical infinite waveguides, if the fields are analysed by means of potentials - the velocity potential for sound waves and the Hertz potentials for electromagnetic waves. It has been demonstrated why these analogies between the potentials representing solutions of the wave equation with adequate boundary conditions and expressed as sums of admissible duct modes do fail, in general, for the semi-infinite cylindrical duct, and why they remain valid when the propagating electromagnetic mode is axisymmetric.
Źródło:
Acta Physica Polonica A; 2009, 116, 3; 410-413
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Exact Phase and its Eikonal Approximation for Class of Reflectionless Index Profiles
Autorzy:
Sharma, S. K.
Ghosh, G.
Powiązania:
https://bibliotekanauki.pl/articles/1963260.pdf
Data publikacji:
1997-03
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
42.25.Fx
41.20.Jb
Opis:
We examine the problem of transmission of electromagnetic waves in a multiparameter reflectionless dielectric. It is shown that it is possible to obtain an analytic form for the phase of the exact transmission amplitude. In the high frequency limit the exact result is found to lead to the eikonal approximation. Interestingly, the high frequency limit and long-range approximation required for the validity of the eikonal approximation are not independent here.
Źródło:
Acta Physica Polonica A; 1997, 91, 3; 555-561
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
TE Surface Waves in a Plasma Sandwich Structure
Autorzy:
Shaikh, M.
Zamir, B.
Ali, R.
Powiązania:
https://bibliotekanauki.pl/articles/1189881.pdf
Data publikacji:
2015-06
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
41.20.Jb
84.40.Az
Opis:
Transverse electric surface waves are analyzed in a plasma medium bounded by a left-handed material. A dispersion relation is obtained by applying the boundary conditions for the tangential field components. Numerical investigations show the dependence of effective wave index on the propagation frequency for different thicknesses and number densities of the plasma medium and also for different values of the filling factor of left-handed material.
Źródło:
Acta Physica Polonica A; 2015, 127, 6; 1625-1629
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Effects of Loss Factor on Plane Wave Propagation through a Left-Handed Material Slab
Autorzy:
Sabah, C.
Powiązania:
https://bibliotekanauki.pl/articles/1812347.pdf
Data publikacji:
2008-06
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
04.30.Nk
41.20.Jb
78.20.Ci
Opis:
This article presents a theoretical and numerical discussion of the reflection and transmission analysis through a lossy left-handed material slab embedded between two semi-infinite dielectric media. The properties of the lossy left-handed material are given in detail and the required equations for the electromagnetic plane wave propagation are derived to solve the problem. The main important contribution of this article is the characterization of left-handed material that is different from its counterpart known in the literature. After introducing the left-handed material slab, the analytical solution is found for the powers carried by an electromagnetic wave. Then, the reflected, the transmitted, and the loss power are computed in terms of the incidence angle, the frequency, and the slab thickness in the numerical results with the emphasis on the loss factor.
Źródło:
Acta Physica Polonica A; 2008, 113, 6; 1589-1597
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Light Localization in Left-Handed Media
Autorzy:
Rusek, M.
Orłowski, A.
Mostowski, J.
Powiązania:
https://bibliotekanauki.pl/articles/2047827.pdf
Data publikacji:
2007-10
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
03.65.Nk
41.20.Jb
72.10.Fk
72.15.Rn
Opis:
Localized waves in disordered left-handed materials are studied using a generalized coupled-dipole model. Resonances in an open system consisting of randomly distributed electric and magnetic dipoles are investigated. A new type of long-lived resonance modes localized at the boundary of the system is found. They resemble evanescent waves responsible for a superfocusing phenomenon by a left-handed lens.
Źródło:
Acta Physica Polonica A; 2007, 112, 4; 673-680
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Study of Two-Dimensional Photonic Crystal Microcavities as a Function of Refractive Index
Autorzy:
Moukhtari, R.
Hocini, A.
Khedrouche, D.
Powiązania:
https://bibliotekanauki.pl/articles/1398722.pdf
Data publikacji:
2016-04
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
42.70.Qs
04.30.Nk
41.20.Jb
42.82.-m
Opis:
Quality factor of two-dimensional photonic crystals microcavity fabricated by SiO₂/ZrO₂ or SiO₂/TiO₂ in which the refractive index varied in the range of 1.51 to 1.58 has been investigated in the present paper. The structure studied consists of circular rods of radius r embedded in air slab, while a is the constant of triangular lattice. Finite difference time domain method with perfectly matched layers was used to calculate the transmission spectrum by FullWAVE software. The results of simulation clearly demonstrate the existences of resonance wavelength of which the position and the highest Q (Q ≈ 4×10⁵) value are strongly affected by refractive index. We demonstrate that the calculated Q factor for the designed cavity increases by a factor of three relative for a cavity without increasing the refractive index.
Źródło:
Acta Physica Polonica A; 2016, 129, 4; 556-558
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Mechanisms of Gap Solitons Formation in Periodic Ferromagnetic Structures
Autorzy:
Morozova, M.
Nikitov, S.
Sharaevskii, Yu.
Sheshukova, S.
Powiązania:
https://bibliotekanauki.pl/articles/1427528.pdf
Data publikacji:
2012-05
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
75.40.Gb
75.70.Ak
41.20.Jb
Opis:
The features of envelope soliton formation in one-dimensional periodic ferromagnetic structure were considered. The model based on the coupled nonlinear Schrödinger equations was used for investigation. The parameter space showing the region in which solitons similar to the Bragg solitons with different features can form was calculated. The mechanisms of the formation of the solitons localized on the limited length of the structure were considered.
Źródło:
Acta Physica Polonica A; 2012, 121, 5-6; 1172-1175
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The Numerical Synthesis of a Radar Signal Having Required Autocorrelation Function
Autorzy:
Leśnik, Cz.
Kawalec, A.
Szugajew, M.
Powiązania:
https://bibliotekanauki.pl/articles/1506803.pdf
Data publikacji:
2010-12
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
41.20.Jb
03.50.De
Opis:
This paper presents the problem of synthesis of signals modulated in frequency with autocorrelation function that implements an optimal approximation to a given autocorrelation function. After theoretical introduction an algorithm of frequency modulated signal synthesis is presented. Simulation results made in Matlab are presented in the last section.
Źródło:
Acta Physica Polonica A; 2010, 118, 6; 1194-1198
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Investigation of Electromagnetic Wave Absorber Based on Carbon Fiber Reinforced Aerated Concrete Using Time-Domain Method
Autorzy:
Laukaitis, A.
Sinica, M.
Balevičius, S.
Levitas, B.
Powiązania:
https://bibliotekanauki.pl/articles/1813404.pdf
Data publikacji:
2008-03
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
41.20.Jb
81.05.Uw
Opis:
The electromagnetic wave absorbers prepared from autoclaved aerated concrete containing carbon fibers as additions in the shape of slabs with pyramids cut on one plane of these slabs were tested using dc microwave source and the time-domain method. It was demonstrated that autoclaved aerated concrete allows one to fabricate electromagnetic wave absorbers which have a reflection coefficient up to -30 dB in the frequency range from 2 GHz to 18 GHz.
Źródło:
Acta Physica Polonica A; 2008, 113, 3; 1047-1050
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Electromagnetic Waves Absorption by Graphene-Magnetic Semiconductor Multilayered Nanostructure in External Magnetic Field: Voight Geometry
Autorzy:
Kuzmin, D.
Bychkov, I.
Shavrov, V.
Powiązania:
https://bibliotekanauki.pl/articles/1386985.pdf
Data publikacji:
2015-02
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
41.20.Jb
42.25.Bs
68.65.Ac
68.65.Cd
68.65.Pq
Opis:
Absorption of electromagnetic waves by graphene-magnetic semiconductor multilayered structure has been investigated for the Voight geometry with taking into account the dissipation processes. The possibility of control of electrodynamic properties of the structure by an external magnetic field, changing in number of periods of the structure, chemical potential of the graphene layers and temperature has been shown. Electrodynamics of the structure is also sensitive to polarization of the incident wave. The structure shows to be especially controllable at terahertz frequencies.
Źródło:
Acta Physica Polonica A; 2015, 127, 2; 528-530
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł

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