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Wyszukujesz frazę "dipole" wg kryterium: Temat


Tytuł:
Strategie klasyfikacji oparte na dipolach
Dipole-based classification strategies
Autorzy:
Topczewska, M.
Frischmuth, K.
Powiązania:
https://bibliotekanauki.pl/articles/155002.pdf
Data publikacji:
2010
Wydawca:
Stowarzyszenie Inżynierów i Techników Mechaników Polskich
Tematy:
klasyfikacja
dipol
kryterium dipolowe
classification
dipole
dipole criterion
Opis:
W pracy przedstawiona została metoda klasyfikacji oparta na kryterium dipolowym. Przeprowadzone testy numeryczne skłoniły autorów do modyfikacji początkowego kryterium prezentowanego w pracy [1] w taki sposób, by znaleziona hiperpłaszczyzna separowała jak największą liczbę obiektów należących do różnych klas, nie rozdzielając obiektów z tej samej klasy. Nowe podejście zostało przetestowane na wygenerowanych zbiorach danych, a otrzymane wyniki pozwoliły na implementację w postaci wywołań rekurencyjnych.
Finding a separating hyperplane for two classes by minimizing an error functional summing contributions for each poorly classified data point is by now common practice. Effective implementations in the framework of SVM or in terms of CPL functions are available and shown to work well for quite large sets of data. In this article a classification method based on dipoles is presented, which is a modification of a criterion given in [1]. We search for a hyperplane cutting between classes and not through their middle. The crux is to define a suitable functional, which is small on lines with good separation power and little damage, easy to calculate and to minimize. We perform numerical tests and modify the criterion in a way that preserves the intention of finding cuts between classes (and not through their middle), which separate as many data points as possible. However, we do not count (in integers), but weigh by taking the distance to the wrong side. The approach was tested on some synthetic data sets using a recursive implementation.
Źródło:
Pomiary Automatyka Kontrola; 2010, R. 56, nr 6, 6; 632-635
0032-4140
Pojawia się w:
Pomiary Automatyka Kontrola
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
On calculations of the dipole moment from the electron density data
Autorzy:
Gryciuk, M.
Górecki, J.
Powiązania:
https://bibliotekanauki.pl/articles/1931585.pdf
Data publikacji:
2002
Wydawca:
Politechnika Gdańska
Tematy:
electron density
dipole moment
grids
Opis:
In the paper we discuss how to calculate the dipole moment using the electron density data. A few numerical methods are compared. We have found that usually the interpolation of electron density gives the most accurate results.
Źródło:
TASK Quarterly. Scientific Bulletin of Academic Computer Centre in Gdansk; 2002, 6, 4; 661-668
1428-6394
Pojawia się w:
TASK Quarterly. Scientific Bulletin of Academic Computer Centre in Gdansk
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
An upper bound for graphs of diameter 3 and given degree obtained as abelian lifts of dipoles
Autorzy:
Vetrík, Tomás
Powiązania:
https://bibliotekanauki.pl/articles/743521.pdf
Data publikacji:
2008
Wydawca:
Uniwersytet Zielonogórski. Wydział Matematyki, Informatyki i Ekonometrii
Tematy:
degree and diameter of a graph
dipole
Opis:
We derive an upper bound on the number of vertices in graphs of diameter 3 and given degree arising from Abelian lifts of dipoles with loops and multiple edges.
Źródło:
Discussiones Mathematicae Graph Theory; 2008, 28, 1; 91-96
2083-5892
Pojawia się w:
Discussiones Mathematicae Graph Theory
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Multiclass classification strategy based on dipoles
Strategia klasyfikacji wieloklasowej oparta na dipolach
Autorzy:
Topczewska, M.
Powiązania:
https://bibliotekanauki.pl/articles/341183.pdf
Data publikacji:
2011
Wydawca:
Politechnika Białostocka. Oficyna Wydawnicza Politechniki Białostockiej
Tematy:
klasyfikacja
problem wieloklasowy
dipol
classification
multiclass problem
dipole
Opis:
The problem of multiclass classification is considered and resolved through the approach based on dipoles. The found hyperplane separates objects from different classes cutting between them and not through their middle. The crux is to define a suitable functional, which is small on lines with good separation power and little damage, easy to calculate and to minimize. The numerical tests were performed and the criterion modified in a way that preserves the intention of finding cuts between classes, which separate as many data points as possible. The approach was tested on some synthetic data sets using a recursive implementation.
W pracy rozpatrywane jest zagadnienie klasyfikacji w przypadku wieloklasowym oraz podejście oparte na dipolach. Poszukiwana hiperpłaszczyzna powinna rozdzielać obiekty należące do różnych klas, ale nie przecinając środka zadnej klasy. Zdefiniowano w tym celu odpowiedni funkcjonał, by przyjmował on małe wartości w przypadku prawidłowej klasyfikacji większości obiektów, był prosty do obliczenia i minimalizacji. Przeprowadzono testy numeryczne oraz dokonano modyfikacji kryterium, by znaleźć takie rozdzielenie klas, by odseparować możliwie dużo obiektów. Podejście było testowane na wybranych syntetycznych zbiorach danych przy wykorzystaniu implementacji w postaci wywołań rekurencyjnych.
Źródło:
Zeszyty Naukowe Politechniki Białostockiej. Informatyka; 2011, 8; 79-90
1644-0331
Pojawia się w:
Zeszyty Naukowe Politechniki Białostockiej. Informatyka
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
O kilku osobliwościach w oddziaływaniach molekuł
On some pecularities of intermolecular and intramolecular interactions
Autorzy:
Piela, L.
Powiązania:
https://bibliotekanauki.pl/articles/172004.pdf
Data publikacji:
2011
Wydawca:
Polskie Towarzystwo Chemiczne
Tematy:
globalna optymalizacja
zwijanie białek
oddziaływanie dipol-dipol
choroba prionowa
autokataliza
global optimization
protein folding
dipole-dipole interaction
prion disease
autocatalysis
Opis:
The ground state electronic energy represents a complicated function of the nuclear coordinates. Even for relatively small molecules this function may have many minima in the corresponding "energy landscape", very often myriads of minima, each of them corresponding to a stable configuration of the nuclei. This is why predicting the lowest-energy conformation or configuration represents a formidable task. There were many attempts to solve this problem for protein molecules, for which it is believed their native conformation corresponds to the lowest free energy. The challenge to find this conformation from a given sequence of amino acids is known as a "second genetic code". In fact all of these attempts based on some smoothing of the energy landscape. In the article some of these smoothing techniques are described, from a generic one to those, which finally turned out to be highly successful in finding native structures of globular proteins. When discussing the contributions to the conformational energy the importance of the hydrophobic effect as well as of the electrostatic interactions has been stressed. In particular it turned out that the dipole moments of the NH and of the CO bonds in proteins functioning in nature are oriented to good accuracy along the local intramolecular electric field. Thanks to enormous effort of the protein folding community it is possible to design such amino acid sequences, which fold to the desired protein 3D structure. A certain reliable theoretical technique of protein folding has been used to study a possibility of conformational autocatalysis. It turned out that a small protein of 32 amino acids, with carefully predesigned amino acid sequence, exhibits indeed such an effect, which may be seen as a model of the prion disease propagation.
Źródło:
Wiadomości Chemiczne; 2011, 65, 11-12; 935-952
0043-5104
2300-0295
Pojawia się w:
Wiadomości Chemiczne
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Efektywność domieszek uplastyczniających do betonu w funkcji ich momentów dipolowych
Effectiveness of plasticizing admixtures for concrete as a function of their dipole moments
Autorzy:
Syczewski, M.
Shirokiy, G.
Juchnevskij, P.
Powiązania:
https://bibliotekanauki.pl/articles/402735.pdf
Data publikacji:
2014
Wydawca:
Politechnika Białostocka. Oficyna Wydawnicza Politechniki Białostockiej
Tematy:
domieszki uplastyczniające
beton
momenty dipolowe
plasticizers
concrete
dipole moments
Opis:
W artykule przedstawiono ocenę metody momentów dipolowych cząsteczek domieszek chemicznych uplastyczniających beton cementowy. W oparciu o przenikalność dialektryczną substancji i wyliczenia momentów dipolowych cząsteczek domieszek, oceniono spadek wilgotności mieszanki betonowej.
Paper presents the evaluation method of dipole molecule moment of plasticizing chemical admixtures for cement concrete. Based on the dielectric permittivity of substance and computation of dipole molecule moments of admixture, decrease of water content in concrete mix was evaluated.
Źródło:
Budownictwo i Inżynieria Środowiska; 2014, 5, 1; 31-34
2081-3279
Pojawia się w:
Budownictwo i Inżynieria Środowiska
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Propagation and Network Analysis for a Dipole Based Massive Mimo Antenna for 5G Base Stations
Autorzy:
Pushpa, Anita Jones Mary
Chrysolite, Samuelraj
Powiązania:
https://bibliotekanauki.pl/articles/2124749.pdf
Data publikacji:
2022
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
5G antenna
massive MIMO
dipole array
maximum gain
Opis:
In today’s fast-paced world, where everyone/everything is moving towards an online platform, the need to provide high-speed data to all is inevitable. Hence, introducing the emerging 5G technology with orthogonal frequency division multiplexing integrated with massive MIMO technology is the need of the hour. A 640 port Massive MIMO (m-MIMO) antenna with high evenly spread gain and very low delay, along with a practically possible data rate operating in the mm waveband, is proposed for a 5G base station. The individual antenna element consists of a dipole (λ=0.5cm) designed to operate at 57GHz. Placing the cylindrical MIMO antenna array (8x20) facing the four directions forming the m-MIMO antenna (160x4) at the height of 3m from ground level for simulation. Achievement of a maximum gain of 23.14dBi (θ=90▫) and a minimum data rate of 1.44Gbps with -10dB bandwidth of 2.1GHz (256-QAM) approximately a distance of 478m from the 5G Base station. The m-MIMO structure gives an Envelope Correlation Coefficient of 0.015. The propagation analysis is carried out to substantiate the performance of the proposed system based on field strength and received power. Network Analysis for better reception performance is carried out by changing the antenna height placement, altering the down tilt of the antenna array, and sweeping the polarization angle of the antenna array.
Źródło:
International Journal of Electronics and Telecommunications; 2022, 68, 3; 511--517
2300-1933
Pojawia się w:
International Journal of Electronics and Telecommunications
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The Different Between the Temperature of the Solar Burst at the Feed Point of the Log Periodic Dipole Antenna (LPDA) and the CALLISTO Spectrometer
Autorzy:
Hamidi, Z. S.
Shariff, N. N. M.
Monstein, C.
Powiązania:
https://bibliotekanauki.pl/articles/411932.pdf
Data publikacji:
2014
Wydawca:
Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN
Tematy:
CALLISTO
Log Periodic Dipole Antenna
LPDA
temperature
solar radio burst
Opis:
The article attempts to analyze and compare the temperature of solar radio burst at the (i) feed point and antenna and (ii) at the receiver (CALLISTO spectrometer). The analysis is very important to evaluate the performance for a better observation of solar radio burst. We start our project by developing this antenna with 19 elements of different sizes covers from 45 − 870 MHz. We choose the National Space Agency (PAN), Sg. Lang, Banting, Selangor, Malaysia as our site seems this site has a very minimum of Radio Frequency Interference (RFI). The antenna, then connects to the low noise amplifier and the CALLISTO spectrometer as one complete system. Based on the results, it was found that the temperature of the at the feed point of the antenna and receiver is different up to 3.25 K. The average level burst level above background sky is about 0.41dB. It was found that the power of solar burst at the feed point of the antenna is equivalent to 2.6 x 10-18 W, but decreases to 2.3 x 10-18 W when detected by the CALLISTO spectrometer. These results show a better understanding of how does the system operate in terms of the process of analysis of the temperature of solar radio burst.
Źródło:
International Letters of Chemistry, Physics and Astronomy; 2014, 11, 2; 167-176
2299-3843
Pojawia się w:
International Letters of Chemistry, Physics and Astronomy
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Application of the Monte Carlo algorithm for solving volume integral equation in light scattering simulations
Autorzy:
Kraszewski, Maciej
Pluciński, Jerzy
Powiązania:
https://bibliotekanauki.pl/articles/174771.pdf
Data publikacji:
2020
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
light scattering
numerical methods
Monte Carlo
discrete dipole approximation
DDA
Opis:
Various numerical methods were proposed for analysis of the light scattering phenomenon. An important group of these methods is based on solving the volume integral equation describing the light scattering process. The popular method from this group is the discrete dipole approximation. Discrete dipole approximation uses various numerical algorithms to solve the discretized integral equation. In the recent years, the application of the Monte Carlo algorithm as one of them was proposed. In this research, we analyze the application of the Monte Carlo algorithm for two cases: the light scattering by large particles and by random conglomerates of small particles. We show that if proper preconditioning of the numerical problem is applied, the Monte Carlo algorithm can solve the underlying systems of linear equations. We also show that the efficiency of the Monte Carlo algorithm can be increased by reusing performed computations for various incident electromagnetic waves and the applicability of the Monte Carlo algorithm depends on the particular use case. It is unlikely to be used in the case of light scattering by the large particles due to computational times inferior comparing with the other numerical methods but may become useful in the case of light scattering by the random conglomerates of small scattering particles.
Źródło:
Optica Applicata; 2020, 50, 1; 1-15
0078-5466
1899-7015
Pojawia się w:
Optica Applicata
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Using the DDA (Discrete Dipole Approximation) Method in Determining the Extinction Cross Section of Black Carbon
Autorzy:
Skorupski, K.
Powiązania:
https://bibliotekanauki.pl/articles/221846.pdf
Data publikacji:
2015
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
black carbon
discrete dipole approximation
light scattering
fractal-like aggregates
Opis:
BC (Black Carbon), which can be found in the atmosphere, is characterized by a large value of the imaginary part of the complex refractive index and, therefore, might have an impact on the global warming effect. To study the interaction of BC with light often computer simulations are used. One of the methods, which are capable of performing light scattering simulations by any shape, is DDA (Discrete Dipole Approximation). In this work its accuracy was estimated in respect to BC structures using the latest stable version of the ADDA (vr. 1.2) algorithm. As the reference algorithm the GMM (Generalized Multiparticle Mie-Solution) code was used. The study shows that the number of volume elements (dipoles) is the main parameter that defines the quality of results. However, they can be improved by a proper polarizability expression. The most accurate, and least time consuming, simulations were observed for IGT_SO. When an aggregate consists of particles composed of ca. 750 volume elements (dipoles), the averaged relative extinction error should not exceed ca. 4.5%.
Źródło:
Metrology and Measurement Systems; 2015, 22, 1; 153-164
0860-8229
Pojawia się w:
Metrology and Measurement Systems
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Design of external microtextures for efficient light outcoupling in OLEDs with different preferential orientation of emission dipoles
Autorzy:
Kovačič, Milan
Powiązania:
https://bibliotekanauki.pl/articles/2074200.pdf
Data publikacji:
2022
Wydawca:
Polska Akademia Nauk. Stowarzyszenie Elektryków Polskich
Tematy:
organic light-emitting diode
light outcoupling
dipole orientation
ray tracing
optical modelling
Opis:
External light outcoupling structures provide a cost-effective and highly efficient solution for light extraction in organic light-emitting diodes. Among them, different microtextures, mainly optimized for devices with isotopically oriented emission dipoles, have been proposed as an efficient light extraction solution. In the paper, the outcoupling for a preferential orientation of emission dipoles is studied for the case of a red bottom-emitting organic light-emitting diode. Optical simulations are used to analyse the preferential orientation of dipoles in combination with three different textures, namely hexagonal array of sine-textures, three-sided pyramids, and random pyramids. It is shown that while there are minimal differences between the optimized textures, the highest external quantum efficiency of 51% is predicted by using the three-sided pyramid texture. Further improvements, by employing highly oriented dipole sources, are examined. In this case, the results show that the top outcoupling efficiencies can be achieved with the same texture shape and size, regardless of the preferred orientation of the emission dipoles. Using an optimized three-sided pyramid in combination with ideally parallel oriented dipoles, an efficiency of 62% is achievable. A detailed analysis of the optical situation inside the glass substrate, dominating external light outcoupling, is presented. Depicted results and their analysis offer a simplified further research and development of external light extraction for organic light-emitting devices with highly oriented dipole emission sources.
Źródło:
Opto-Electronics Review; 2022, 30, 2; art. no. e141542
1230-3402
Pojawia się w:
Opto-Electronics Review
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
A Dual-Band Compact Integrated Rectenna for Implantable Medical Devices
Autorzy:
Hussein, Shamil H.
Mohammed, Khalid K.
Powiązania:
https://bibliotekanauki.pl/articles/27311860.pdf
Data publikacji:
2023
Wydawca:
Polska Akademia Nauk. Czasopisma i Monografie PAN
Tematy:
Implantable rectenna
Folded Dipole Antenna FDA
Phantom tissues layers
CST suit
simulation
Opis:
This work describes a dual band compact fully integrated rectenna circuit for implantable medical devices (IMDs). The implantable rectenna circuit consists of tunnel diode 10×10μm2 QW-ASPAT (Quantum Well Asymmetric Spacer Tunnel Layer diode) was used as the RF-DC rectifier due to its temperature insensitivity and nonlinearity compared with conventional SBD diode. SILVACO atlas software is used to design and simulate 100μm2 QW InGaAs ASPAT diode. A miniaturized dual band implantable folded dipole antenna with multiple L-shaped conducting sections is designed using CST microwave suits for operation in the WMTS band is 1.5GHz and ISM band of 5.8GHz. High dielectric constant material Gallium Arsenide (εr=12.94) and folded geometry helps to design compact antennas with a small footprint of 2.84mm3 (1×4.5×0.63) mm3. Four-layer human tissue model was used, where the antenna was implanted in the skin model at depth of 2mm. The 10-dB impedance bandwidth of the proposed compact antenna at 1.5GHz and 5.8GHz are 227MHz (1.4-1.63GHz) with S11 is -22.6dB and 540MHz (5.47-6.02GHz) with S11 is -23.1dB, whereas gains are -36.9dBi, and -24.3dBi, respectively. The output DC voltage and power of the rectenna using two stage voltage doubler rectifier (VDR) are twice that produced by the single stage at input RF power of 10dBm.
Źródło:
International Journal of Electronics and Telecommunications; 2023, 69, 2; 239--245
2300-1933
Pojawia się w:
International Journal of Electronics and Telecommunications
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Properties of water hydrating the galactolipid and phospholipid bilayers: a molecular dynamics simulation study
Autorzy:
Markiewicz, Michał
Baczyński, Krzysztof
Pasenkiewicz-Gierula, Marta
Powiązania:
https://bibliotekanauki.pl/articles/1038986.pdf
Data publikacji:
2015
Wydawca:
Polskie Towarzystwo Biochemiczne
Tematy:
molecular modelling
hydrogen bonds
water diffusion
water dipole orientation
inter-lamellar water
Opis:
Molecular dynamics simulations of 1,2-di-O-acyl-3-O-β-D-galactopyranosyl-sn-glycerol (MGDG) and 1,2-dioleoyl-sn-glycero-3-phosphatidylcholine (DOPC) bilayers were carried out to compare the effect of the lipid head group's chemical structure on the dynamics and orientational order of the water molecules hydrating the bilayer. The effect of the bilayers on the diffusion of water is strong for the neighbouring water molecules i.e., those located not further than 4 Å from any bilayer atom. This is because the neighbouring water molecules are predominantly hydrogen bonded to the lipid oxygen atoms and their mobility is limited to a confined spatial volume. The choline group of DOPC and the galactose group of MGDG affect water diffusion less than the polar groups located deeper in the bilayer interface, and similarly. The latter is an unexpected result since interactions of water with these groups have a vastly different origin. The least affected by the bilayer lipids is the lateral diffusion of unbound water in the bilayer plane (x,y-plane) - it is because the diffusion is not confined by the periodic boundary conditions, whereas that perpendicular to the plane is. Interactions of water molecules with lipid groups also enforce certain orientations of water dipole moments. The profile of an average water orientation along the bilayer normal for the MGDG bilayer differs from that for the DOPC bilayer. In the DOPC bilayer, the ordering effect of the lipid head groups extends further into the water phase than in the MGDG bilayer, whereas inside the bilayer/water interface, ordering of the water dipoles in the MGDG bilayer is higher. It is possible that differences in the profiles of an average water orientation across the bilayer in the DOPC and MGDG bilayers are responsible for differences in the lateral pressure profiles of these bilayers.
Źródło:
Acta Biochimica Polonica; 2015, 62, 3; 475-481
0001-527X
Pojawia się w:
Acta Biochimica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Hidden Connections Between NanoTesla Magnetic Fields, Cosic Molecular Resonance, and Photonic Fields Within Living Systems
Autorzy:
Persinger, Michael A.
Powiązania:
https://bibliotekanauki.pl/articles/1188077.pdf
Data publikacji:
2016
Wydawca:
Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN
Tematy:
Cosic RRM; photon flux; nanoTesla magnetic fields; 10-20 Joules; Hu-Wu dipole-dipole effects; Bokkon photonic fields; ultraweak biophoton emissions
excess correlation
geomagnetic activity
spectral power densities
Opis:
The interfaces between molecules and the interactions between cells involve very small energies (~10-20 J) and photon flux densities (~10-12 W•m-2) that ultimately control the dynamics and health of the human body. Within the environment there is an increment (± 3 nT) of weak magnetic field fluctuations whose energies within the volume of the human brain display the capacities to affect its properties through nuclear spins in neural membranes. There is a conservation of energy. Within the same volume when there are increases in photon flux densities from cells and human cerebrums there are decreases of interfacial geomagnetic field intensities within the nanoTesla range. The spectral power densities of the sequential quantifications of pseudopotentials of the amino acids that compose proteins and the nucleotides that construct DNA and RNA predict the functions of molecular pathways as electromagnetic resonances. They operate through these small energies, photon flux densities, and fluctuating magnetic fields. Whereas metabolic-level energies operate the mechanics of the multivariate molecular pathways for cell signaling the photon wavelengths predicted by the Cosic Resonant Recognition Model may be the templates and the initiators. The involvement of specific peaks of photon wavelengths that are the energetic equivalents of molecular structures containing intrinsic phase-modulations creates the conditions for excess correlations (“entanglement”) and potential non-locality within the total human environment. This alternative perspective may facilitate developments of different strategies and technologies for solving the challenges of global public health in the 21st century.
Źródło:
World Scientific News; 2016, 56; 1-20
2392-2192
Pojawia się w:
World Scientific News
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Determination of Flux Density of the Solar Radio Burst Event by Using Log Periodic Dipole Antenna (LPDA)
Autorzy:
Hamidi, Z. S.
Shariff, N. N. M.
Powiązania:
https://bibliotekanauki.pl/articles/412450.pdf
Data publikacji:
2014
Wydawca:
Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN
Tematy:
sun
CALLISTO
Log Periodic Dipole Antenna (LPDA)
power flux density
solar radio burst
Opis:
In this article, an evaluation of the flux density of the solar radio burst is presented. A rod aluminium’s type as a conductor with nineteenth (19) elements of different sizes is being prepared to construct a log periodic dipole antenna (LPDA) from 45-870 MHz. The performance was carried out at the National Space Agency (PAN), Sg. Lang, Banting Selangor by connecting to the Compound Low Cost Low Frequency Spectroscopy Transportable Observatory (CALLISTO) spectrometer. The input impedance, R0 = 50 ohm is chosen for this LPDA antenna. From the analysis, the gain of the antenna is 9.3 dB. This antenna potentially captures a signal that covers about 0.08 m2 area of the Sun.The temperature of the burst that detected at the feedpoint of the antenna is 32 K. However, the signal becomes decrease to 28.75 K while by CALLISTO spectrometer as a receiver. It was also found that the isotropic source spectral power is 1576 W/Hz. Since the burst level above the background sky is 0.41 dB , the flux density of the burst is 5.5 x 10-21 W/m2/Hz. Based on the results, we conclude that this antenna is suitable for to observe the Sun activities at low frequency region.
Źródło:
International Letters of Chemistry, Physics and Astronomy; 2014, 7; 21-29
2299-3843
Pojawia się w:
International Letters of Chemistry, Physics and Astronomy
Dostawca treści:
Biblioteka Nauki
Artykuł

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