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    Wyświetlanie 1-28 z 28
    Tytuł:
    Approximation of random sums of random variables in insurance
    Autorzy:
    Wlaź, P.
    Powiązania:
    https://bibliotekanauki.pl/articles/102826.pdf
    Data publikacji:
    2014
    Wydawca:
    Stowarzyszenie Inżynierów i Techników Mechaników Polskich
    Tematy:
    random sum
    fast Fourier transform
    shifted gamma distribution
    Opis:
    The paper deals with approximations of random sums. By random sum we mean a sum of random number of independent and identically distributed random variables. Distribution of this sum is called a compound distribution. The model is especially important in non-life insurance. There are many methods for approximating compound distributions, one of the most popular one is approximation with shifted gamma distribution. In this work we show an alternative way – using kernel density, Fast Fourier Transform and numerical optimization methods – for finding shifted gamma approximations and show results suggesting its superiority over classical method.
    Źródło:
    Advances in Science and Technology. Research Journal; 2014, 8, 23; 88-93
    2299-8624
    Pojawia się w:
    Advances in Science and Technology. Research Journal
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Comparative Study on the Frictional Sound Properties of Woven Fabrics
    Badanie porównawcze właściwości dźwięku tarcia tkanin
    Autorzy:
    Wang, P.-N.
    Ho, M.-H.
    Cheng, K.-B.
    Murray, R.
    Lin, C.-H.
    Powiązania:
    https://bibliotekanauki.pl/articles/233866.pdf
    Data publikacji:
    2017
    Wydawca:
    Sieć Badawcza Łukasiewicz - Instytut Biopolimerów i Włókien Chemicznych
    Tematy:
    KES-FB
    fast Fourier transform
    auto-regressive coefficients
    LPTS
    transformat Fouriera
    współczynnik regresji
    Opis:
    An innovative Frictional Sound Automatic Measuring System (FSAMS) was designed to collect and enable analysis of the frictional sound spectra of four natural fibre woven fabrics which included cotton, linen, silk, and wool. The Fast Fourier Transform (FFT) method was used to convert time-domain signals into frequency-domain signals to enable the maximum sound amplitude (MSA) and the level pressure of the total sound (LPTS) of the cotton, linen, silk, and wool fabrics to be calculated and analysed. Subsequently auto-regression formulae were used to calculate the fabric auto-regressive coefficients (ARC, ARF, and ARE); the correlations between fabric frictional sound in terms of LPTS and AR coefficients, and mechanical properties as measured by KES-FB were also evaluated. Stepwise regression was then used to identify the key frictional sound parameters for the four types of fabric. The results show that LPTS values for cotton, linen, silk, and wool fabrics increase with their ARC values. It was revealed that the key mechanical parameters affecting fabric frictional sound for the four natural fibre woven fabrics were not the same for each fabric type: the parameters that influenced LPTS values were the fabric weight and bending hysteresis for the cotton fabric, tensile energy for the linen, tensile resilience for the silk and shear hysteresis at a 5° shear angle for the wool fabric.
    Do analizy spektrum akustycznego czterech tkanin (bawełnianej, lnianej, jedwabnej i wełnianej) zastosowano innowacyjny system automatycznego pomiaru dźwięku tarcia (FSAMS). Do przekształcania sygnałów w dziedzinie czasu w sygnały w dziedzinie częstotliwości wykorzystano metodę szybkiej transformaty Fouriera (FFT). Następnie obliczono współczynniki autoregresji tkanin (ARC, ARF i ARE) i oceniono właściwości mechaniczne tkanin. Wyniki pokazują, że wartości poziomu ciśnienia dźwięku totalnego (LPTS) dla tkanin bawełnianych, lnianych, jedwabnych i wełnianych wzrastają wraz z wartościami współczynnika ARC. Wykazano również, że kluczowe parametry mechaniczne wpływające na tarcie tkaniny nie były takie same dla wszystkich typów tkanin. Parametrami mechanicznymi wpływającymi na wartości LPTS tkaniny bawełnianej były: ciężar i histereza zginania tkaniny, w przypadku tkaniny lnianej największy wpływ miała siła rozciągania, a w przypadku tkaniny wełnianej sprężystość powrotna.
    Źródło:
    Fibres & Textiles in Eastern Europe; 2017, 4 (124); 36-44
    1230-3666
    2300-7354
    Pojawia się w:
    Fibres & Textiles in Eastern Europe
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Study on the Friction Sound Properties of Natural-Fiber Woven Fabrics
    Badanie dźwięku ciernego tkanin z włókien naturalnych
    Autorzy:
    Wang, P.-N.
    Ho, M.-H.
    Cheng, K.-B.
    Murray, R.
    Lin, C.-H.
    Powiązania:
    https://bibliotekanauki.pl/articles/232653.pdf
    Data publikacji:
    2017
    Wydawca:
    Sieć Badawcza Łukasiewicz - Instytut Biopolimerów i Włókien Chemicznych
    Tematy:
    fabric sound automatic measuring system
    sound level pressure
    fast Fourier transform
    włókna naturalne
    pomiar dźwięku ciernego
    poziom hałasu
    transformat Fouriera
    Opis:
    An innovative frictional sound automatic measuring system (FSAMS) was designed and used in this study to investigate the frictional sound generated when natural-fibre woven fabrics are rubbed together. Frictional sound measurements made using the automatic FSAMS were compared with those from a manual frictional sound measuring system (Manual FSAMS). The frictional sounds of four natural-fiber woven fabrics (i.e., cotton, linen, silk, and wool) were recorded; the Fast Fourier Transform method was used to convert time domain signals into frequency domain signals, and the maximum sound amplitude (MSA) and level pressure of the total sound (LPTS) of cotton, linen, silk, and wool were calculated. The results of a t test, analysis of variance, data reproducibility, and cluster spectrums measured from the four natural-fiber woven fabrics were compared for the two test equipment systems. The results from the t test and analysis of variance showed significant differences in the MSA and LPTS measured. Data reproducibility was superior to the automatic FSAMS compared with the manual FSAMS, and the cluster spectrums were more readily distinguishable.
    W celu zbadania szumu generowanego podczas tarcia o siebie tkanin z włókien naturalnych zaprojektowano i wykorzystano innowacyjny, automatyczny system pomiaru dźwięku ciernego (FSAMS). Porównano wyniki otrzymane za pomocą FSAMS z wynikami otrzymanymi przy użyciu systemu manualnego (Manual FSAMS). Do badania użyto czterech tkanin z włókien naturalnych: bawełny, lnu, jedwabiu i wełny. Przeprowadzono analizę statystyczną otrzymanych wyników. Analiza danych wykazała, że wartości szumu zmierzone przy użyciu FSAMS były bardziej stabilne i reprezentatywne, niż te otrzymane przy użyciu Manual FSAMS, ponieważ w przypadku systemu manualnego na wyniki pomiaru ma wpływ czynnik ludzki i hałasy otoczenia, które powodują duże błędy eksperymentalne.
    Źródło:
    Fibres & Textiles in Eastern Europe; 2017, 2 (122); 34-42
    1230-3666
    2300-7354
    Pojawia się w:
    Fibres & Textiles in Eastern Europe
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Fabrication and geometric characterization of highly-ordered hexagonally arranged arrays of nanoporous anodic alumina
    Autorzy:
    Stępniowski, W. J.
    Nowak-Stępniowska, A.
    Michalska-Domańska, M.
    Norek, M.
    Czujko, T.
    Bojar, Z.
    Powiązania:
    https://bibliotekanauki.pl/articles/779908.pdf
    Data publikacji:
    2014
    Wydawca:
    Zachodniopomorski Uniwersytet Technologiczny w Szczecinie. Wydawnictwo Uczelniane ZUT w Szczecinie
    Tematy:
    nanopores
    anodization
    self-organization
    fast Fourier transform
    Opis:
    Anodic aluminum oxide (AAO) has been fabricated in the 0.3 M oxalic acid at voltage range 20-60 V and temperature range of 35-50oC. The resulting nanoporous alumina surfaces were characterized by high resolution scanning electron microscopy, and the images were quantitatively analysed by means of an innovative approach based on fast Fourier transform. The influence of operating anodization voltage and electrolyte temperature on nanopores geometry (pore diameter, interpore distance, porosity, pores density) and arrangement has been studied in details and compared to literature data and theoretical calculations. It was found that independently from the temperature, the best arrangement of the nanopores is for anodic aluminum oxide formed at voltages ranging from 40 to 50 V. Moreover, it was found that pore diameter and interpore distance increase linearly with voltage, what is in line with the literature data.
    Źródło:
    Polish Journal of Chemical Technology; 2014, 16, 1; 63-69
    1509-8117
    1899-4741
    Pojawia się w:
    Polish Journal of Chemical Technology
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Chaotic assessment of the heave and pitch dynamics motions of air cushion vehicles
    Autorzy:
    Sowayan, A. S.
    Powiązania:
    https://bibliotekanauki.pl/articles/1839831.pdf
    Data publikacji:
    2021
    Wydawca:
    Uniwersytet Zielonogórski. Oficyna Wydawnicza
    Tematy:
    transformata Fouriera
    poduszka powietrzna
    model pojazdu
    air cushion vehicles
    Poincaré map
    fast Fourier transform
    heave motion
    pitching motion
    Opis:
    In this study, a three degrees of freedom nonlinear air cushion vehicle (ACV) model is introduced to examine the dynamic behavior of the heave and pitch responses in addition to the cushion pressure of the ACV in both time and frequency domains. The model is based on the compressible flow Bernoulli’s equation and the thermodynamics nonlinear isentropic relations along with the Newton second law of translation and rotation. In this study, the dynamical investigation was based on a numerical simulation using the stiff ODE solvers of the Matlab software. The chaotic investigations of the proposed model are provided using the Fast Fourier Transform (FFT), the Poincaré maps, and the regression analysis. Three control design parameters are investigated for the chaotic studies. These parameters are: ACV mass (M), the mass flow rate entering the cushion volume (in), and the ACV base radius (r). Chaos behavior was observed for heave, and pitch responses as well as the cushion pressure.
    Źródło:
    International Journal of Applied Mechanics and Engineering; 2021, 26, 2; 219-234
    1734-4492
    2353-9003
    Pojawia się w:
    International Journal of Applied Mechanics and Engineering
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    On configuration of residue scaling process in pipelined radix-4 MQRNS FFT processor
    Autorzy:
    Smyk, R.
    Czyżak, M.
    Powiązania:
    https://bibliotekanauki.pl/articles/377692.pdf
    Data publikacji:
    2014
    Wydawca:
    Politechnika Poznańska. Wydawnictwo Politechniki Poznańskiej
    Tematy:
    fast Fourier transform
    residue number system
    modified quadratic residue number system
    FFT pipelined processor
    Opis:
    Residue scaling is needed in pipelined FFT radix-4 processors based on the Modified Quadratic Residue Number System (MQRNS) at the output of each butterfly. Such processor uses serial connection of radix-4 butterflies. Each butterfly comprises n subunits, one for each modulus of the RNS base and generates four complex residue numbers. In order to prevent the arithmetic overflow in the succesive stage, every number has to be scaled, i.e. divided by a certain constant. The dynamic range of the processed signal increases due to the summation within the butterfly and the transformation of coefficients of the FFT algorithm to integers. The direct approach would require eight residue scalers that would be highly ineffective regarding that such a set of scalers had to be placed after each butterfly. We show and analyze a structure which uses parallel-to-serial transformation of groups of numbers so that only two scalers are needed.
    Źródło:
    Poznan University of Technology Academic Journals. Electrical Engineering; 2014, 80; 145-150
    1897-0737
    Pojawia się w:
    Poznan University of Technology Academic Journals. Electrical Engineering
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    On simplification of residue scaling process in pipelined Radix-4 MQRNS FFT processor
    Autorzy:
    Smyk, R.
    Czyżak, M.
    Powiązania:
    https://bibliotekanauki.pl/articles/97551.pdf
    Data publikacji:
    2014
    Wydawca:
    Politechnika Poznańska. Wydawnictwo Politechniki Poznańskiej
    Tematy:
    fast Fourier transform
    residue number system
    modified quadratic residue number system
    pipelined FFT processor
    Opis:
    Residue scaling is needed in pipelined FFT radix-4 processors based on the Modified Quadratic Residue Number System (MQRNS) at the output of each butterfly. Such processor uses serial connection of radix-4 butterflies. Each butterfly comprises n subunits, one for each modulus of the RNS base and generates four complex residue numbers. In order to prevent arithmetic overflow intermediate results after each butterfly have to be scaled, i.e. divided by a certain constant. The number range of the processed signal increases due to transformation of coefficients of the FFT algorithm to integers and summation and multiplication within the butterfly. The direct approach would require eight residue scalers that would be highly ineffective regarding that such a set of scalers had to be placed after each butterfly. We show and analyze a structure which uses parallel-to-serial transformation of groups of numbers so that only two residue scalers are needed.
    Źródło:
    Computer Applications in Electrical Engineering; 2014, 12; 588-596
    1508-4248
    Pojawia się w:
    Computer Applications in Electrical Engineering
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    The heat transfer and flow structure analyses of low concentration copper nanofluids in a strong magnetic field
    Autorzy:
    Roszko, A.
    Fornalik-Wajs, E.
    Powiązania:
    https://bibliotekanauki.pl/articles/175547.pdf
    Data publikacji:
    2015
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    nanofluids
    heat transfer
    flow structure
    fast Fourier transform
    Nusselt number ratio
    thermomagnetic Rayleigh number
    Opis:
    Main aim of this paper was to analyze the influence of strong magnetic field on the enhancement or suppression of nanofluids transport processes. The second objective was to determine how the flow structure changed under the influence of a magnetic field. Analyzed diamagnetic nanofluids composed of distilled water and the copper nanoparticles of 40–60 nm size in three different concentrations (50, 500, and 1000 ppm). The experimental enclosure position in the magnet test section caused the most intricate interaction of the acting forces: the gravitational and magnetic buoyancy ones, and made the interpretation of results very difficult. The Nusselt number ratio and the thermomagnetic Rayleigh number were determined for heat transfer analysis, while the fast Fourier transform was performed for the nanofluid flow structure analysis. Spectral analysis for all examined nanofluids was presented. Influence of nanoparticles concentration was clearly visible, while the direct impact of magnetic field on the heat transfer and flow structure should be still investigated.
    Źródło:
    Transactions of the Institute of Fluid-Flow Machinery; 2015, 128; 29-42
    0079-3205
    Pojawia się w:
    Transactions of the Institute of Fluid-Flow Machinery
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Performance and stability analysis of series-cascaded, high-gain, interleaved boost converter for photovoltaic applications
    Autorzy:
    Prasanna Kumar, C.
    Venugopal, N.
    Powiązania:
    https://bibliotekanauki.pl/articles/1193536.pdf
    Data publikacji:
    2018
    Wydawca:
    Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
    Tematy:
    series cascade
    interleaved boost converter
    high gain
    stability
    fast Fourier transform
    Opis:
    Interleaved boost converters (IBCs) are cascaded in parallel in most of the applications. This novel approach connects IBC in series cascade. The IBC has an optimal operating duty cycle of 0.5. Normally, photovoltaic source voltage is low because of space constraints. In order to boost the source voltage, a conventional boost converter is replaced with series-cascaded IBC in this paper. The single-stage IBC also boosts the voltage to twice the input voltage. In the proposed converter, output voltage is about four times the input voltage with the same 0.5 duty cycle. A mathematical model is developed and simulated for the proposed work in MATLAB/Simulink platform. The output of the proposed circuit is analysed through fast Fourier transform to know the harmonic content due to the switching. The system is tested for stability with signal-flow graph modelling. The proposed work is realised using hardware and tested to validate the model.
    Źródło:
    Power Electronics and Drives; 2018, 3, 38; 85-97
    2451-0262
    2543-4292
    Pojawia się w:
    Power Electronics and Drives
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Application of Spectral and Wavelet Analysis of Stator Current to Detect Angular Misalignment in PMSM Drive Systems
    Autorzy:
    Pietrzak, Przemysław
    Wolkiewicz, Marcin
    Powiązania:
    https://bibliotekanauki.pl/articles/1956007.pdf
    Data publikacji:
    2021
    Wydawca:
    Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
    Tematy:
    fault diagnosis
    permanent magnet synchronous motor
    angular misalignment
    fast Fourier transform
    discrete wavelet transform
    Opis:
    This paper deals with the selected methods of detecting angular misalignment in drive systems with a permanent magnet synchronous motor (PMSM), which are based on the analysis of the stator phase current signal, as well as their experimental verification and comparison. The proposed and compared methods are spectral analysis and wavelet analysis of the stator current, stator current envelope, stator current space vector module. Furthermore, the influence of power supply frequency and load torque on the performance of the proposed diagnostic methods is also discussed. The experimental tests were carried out for an undamaged motor and for two levels of angular misalignment. The article discusses the question of exactly what damage symptoms can be extracted from each of the methods. In the case of spectral analyses, it is demonstrated which multiplicities of the failure frequency are the most sensitive to misalignment and the least sensitive to changes in motor operating condition, which may be considered novel in the case of drive systems with permanent magnet motors. It is also proven that discrete wavelet transform (DWT) of the envelope and monitoring of the value of the relevant components allows the detection of misalignment with the availability of measuring current only in one phase in various motor operating conditions.
    Źródło:
    Power Electronics and Drives; 2021, 6, 41; 42-60
    2451-0262
    2543-4292
    Pojawia się w:
    Power Electronics and Drives
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Stator winding fault detection of permanent magnet synchronous motors based on the bispectrum analysis
    Autorzy:
    Pietrzak, Przemysław
    Wolkiewicz, Marcin
    Powiązania:
    https://bibliotekanauki.pl/articles/2173641.pdf
    Data publikacji:
    2022
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    fault diagnosis
    condition monitoring
    inter-turn short circuits
    permanent magnet synchronous motor
    bispectrum
    fast Fourier transform
    błędna diagnoza
    monitorowanie stanu
    zwarcia międzyzwojowe
    silnik synchroniczny z magnesami trwałymi
    bispektrum
    szybka transformata Fouriera
    Opis:
    The popularity of high-efficiency permanent magnet synchronous motors in drive systems has continued to grow in recent years. Therefore, also the detection of their faults is becoming a very important issue. The most common fault of this type of motor is the stator winding fault. Due to the destructive character of this failure, it is necessary to use fault diagnostic methods that facilitate damage detection in its early stages. This paper presents the effectiveness of spectral and bispectrum analysis application for the detection of stator winding faults in permanent magnet synchronous motors. The analyzed diagnostic signals are stator phase current, stator phase current envelope, and stator phase current space vector module. The proposed solution is experimentally verified during various motor operating conditions. The object of the experimental verification was a 2.5 kW permanent magnet synchronous motor, the construction of which was specially prepared to facilitate inter-turn short circuits modelling. The application of bispectrum analysis discussed so far in the literature has been limited to vibration signals and detecting mechanical damages. There are no papers in the field of motor diagnostic dealing with the bispectrum analysis for stator winding fault detection, especially based on stator phase current signal.
    Źródło:
    Bulletin of the Polish Academy of Sciences. Technical Sciences; 2022, 70, 2; art. no. e140556
    0239-7528
    Pojawia się w:
    Bulletin of the Polish Academy of Sciences. Technical Sciences
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Identyfikacja wybuchów podziemnych i tąpnięć kopalnianych na podstawie pomiarów widm i energii zarejestrowanych drgań
    Identification of explosions and tremors of underground mine based on measurements of the energy spectra and registered vibrations
    Autorzy:
    Piesiak, S.
    Jamroziak, K.
    Jarguliński, W.
    Powiązania:
    https://bibliotekanauki.pl/articles/137178.pdf
    Data publikacji:
    2015
    Wydawca:
    Uczelnia Jana Wyżykowskiego
    Tematy:
    tąpnięcia kopalniane
    transformata Fouriera
    widmo obciążeń
    energia drgań sejsmicznych
    analiza mocy drgań
    mine tremors
    fast Fourier transform
    load spectrum
    seismic energy
    power analysis of vibration
    Opis:
    Autorzy proponują ciągły monitoring mocy drgań trzęsień wulkanicznych, morskich i tąpnięć kopalnianych. Oparty jest on na nowym sposobie przetwarzania rejestrowanych sygnałów przemieszczeń, prędkości i przyspieszeń. Wykorzystano w tym celu specjalistyczne oprogramowanie pozwalające zastosować szybką transformatę Fouriera (FFT), określono liczbę harmonik i ich amplitudy w przyjętym przedziale czasowym, w którym badano zjawisko drgań.
    The authors suggested continuous monitoring the power of vibration of volcanic earthquakes, marine and mining tremors. New method of processing recorded signals of displacements, velocities and accelerations was introduced. Special software of use the Fast Fourier Transform (FFT) to set a number of harmonics and their amplitudes in the adopted timeframe was used to analyze the vibration phenomenon.
    Źródło:
    Zeszyty Naukowe Dolnośląskiej Wyższej Szkoły Przedsiębiorczości i Techniki. Studia z Nauk Technicznych; 2015, 4; 205-216
    2299-3355
    Pojawia się w:
    Zeszyty Naukowe Dolnośląskiej Wyższej Szkoły Przedsiębiorczości i Techniki. Studia z Nauk Technicznych
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Diagnosis of ITSC fault in the electrical vehicle powertrain system through signal processing analysis
    Autorzy:
    Ouamara, Dehbia
    Boukhnifer, Moussa
    Chaibet, Ahmed
    Maidi, Ahmed
    Powiązania:
    https://bibliotekanauki.pl/articles/2174472.pdf
    Data publikacji:
    2023
    Wydawca:
    Polska Akademia Nauk. Polskie Towarzystwo Diagnostyki Technicznej PAN
    Tematy:
    induction motor
    electrical vehicle
    fault diagnosis
    inter-turn short circuit
    extended Kalman filter
    spectral analysis
    fast Fourier transform
    short-time Fourier transform
    silnik indukcyjny
    pojazd elektryczny
    diagnostyka uszkodzeń
    zwarcie międzyzwojowe
    rozszerzony filtr Kalmana
    analiza spektralna
    szybka transformata Fouriera
    krótkoczasowa transformata Fouriera
    Opis:
    The three-phase induction motor is well suited for a wide range of mobile drives, specifically for electric vehicle powertrain. During the entire life cycle of the electric motor, some types of failures can occur, with stator winding failure being the most common. The impact of this failure must be considered from the incipient as it can affect the performance of the motor, especially for electrically powered vehicle application. In this paper, the intern turn short circuit of the stator winding was studied using Fast Fourier transform (FFT) and Shor-Time Fourier transform (STFT) approaches. The residuals current between the estimated currents provided by the extended Kalman filter (EKF) and the actual ones are used for fault diagnosis and identification. Through FFT, the residual spectrum is sensitive to faults and gives the extraction of inter-turn short circuit (ITSC) related frequencies in the phase winding. In addition, the FFT is used to obtain information about when and where the ITSC appears in the phase winding. Indeed, the results allow to know the faulty phase, to estimate the fault rate and the fault occurrence frequency as well as their appearance time.
    Źródło:
    Diagnostyka; 2023, 24, 1; art. no. 2023113
    1641-6414
    2449-5220
    Pojawia się w:
    Diagnostyka
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Effect of ADC Resolution on Low-Frequency Electrical Time-Domain Impedance Spectroscopy
    Autorzy:
    Namin, R. L.
    Ashtiani, S. J.
    Powiązania:
    https://bibliotekanauki.pl/articles/221144.pdf
    Data publikacji:
    2017
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    electrical impedance spectroscopy
    analogue-to-digital converter
    Ramp signal
    fast Fourier transform
    Nyquist plot
    Opis:
    In this paper, the effect of the resolution of an analogue-to-digital converter (ADC) on the accuracy of timedomain low-frequency electrical impedance spectroscopy is examined. For the first time, we demonstrated that different wideband stimuli signals used for impedance spectroscopy have different sensitivities to the resolution of ADC used in impedance spectroscopy systems. We also proposed Ramp and Half-Gaussian signals as new wideband stimulating signals for EIS. The effect of ADC resolution was studied for Sinc, Gaussian, Half-Gaussian, and Ramp excitation signals using both simulation and experiments. We found that Ramp and Half-Gaussian signals have the best performance, especially at low frequencies. Based on the results, a wideband electrical impedance spectroscopy circuit was implemented with a high accuracy at frequencies bellow 10 Hz.
    Źródło:
    Metrology and Measurement Systems; 2017, 24, 2; 425-436
    0860-8229
    Pojawia się w:
    Metrology and Measurement Systems
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Using the MIMO method to evaluate the modal properties of the elements of a wheelset in an active experiment
    Autorzy:
    Milewicz, Julia
    Mokrzan, Daniel
    Nowakowski, Tomasz
    Szymański, Grzegorz M.
    Powiązania:
    https://bibliotekanauki.pl/articles/24202007.pdf
    Data publikacji:
    2022
    Wydawca:
    Politechnika Poznańska. Instytut Mechaniki Stosowanej
    Tematy:
    modal analysis
    FRF
    fast Fourier transform
    light railway vehicle
    wheelset
    analiza modalna
    szybka transformata Fouriera
    lekki pojazd szynowy
    zestaw kołowy
    Opis:
    The study of the system composed of the inner disc and wheel rim of the 105Na type railway wheel, used in Polish Konstal streetcars, was aimed at determining the dynamic parameters of the object, such as the form and frequency of natural vibrations, and at evaluating the effectiveness of the method at given analysis settings. The experiment was conducted using triaxial piezoelectric transducers and a modal hammer with an aluminum head. A multiple-input, multiple-output (MIMO) testing approach was used because of the multiple excitation points and vibration measurements. A Fast Fourier Transform (FFT) of the measurements was performed in BK Connect software and the frequency response function (FRF) value waveforms were determined. The Rational Fraction Polynomial-Z method was used to extract modes from the frequency spectrum. In addition, the Complex Mode Indicator Function method was used, which resulted in the decomposition of the principal components of the FRF value matrix, allowing the identification of individual modes. The selection of the natural frequencies was performed on the basis of the obtained FRF and CMIF characteristics of the vibroacoustic response. Visualization of the form of the natural vibration was also performed. The result of the experiment was a set of comprehensive information on the modal properties of the studied object, which allowed to confirm the effectiveness of the selected method of analysis.
    Źródło:
    Vibrations in Physical Systems; 2022, 33, 3; art. no. 2022324
    0860-6897
    Pojawia się w:
    Vibrations in Physical Systems
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Infrasound Signal Classification Based on ICA and SVM
    Autorzy:
    Lu, Quanbo
    Wang, Meng
    Li, Mei
    Powiązania:
    https://bibliotekanauki.pl/articles/31339863.pdf
    Data publikacji:
    2023
    Wydawca:
    Polska Akademia Nauk. Czasopisma i Monografie PAN
    Tematy:
    independent component analysis
    fast Fourier transform
    support vector machine
    infrasound signal
    Opis:
    A diagnostic technique based on independent component analysis (ICA), fast Fourier transform (FFT), and support vector machine (SVM) is suggested for effectively extracting signal features in infrasound signal monitoring. Firstly, ICA is proposed to separate the source signals of mixed infrasound sources. Secondly, FFT is used to obtain the feature vectors of infrasound signals. Finally, SVM is used to classify the extracted feature vectors. The approach integrates the advantages of ICA in signal separation and FFT to extract the feature vectors. An experiment is conducted to verify the benefits of the proposed approach. The experiment results demonstrate that the classification accuracy is above 98.52% and the run time is only 2.1 seconds. Therefore, the proposed strategy is beneficial in enhancing geophysical monitoring performance.
    Źródło:
    Archives of Acoustics; 2023, 48, 3; 191-199
    0137-5075
    Pojawia się w:
    Archives of Acoustics
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    The analysis of vibrations in the vehicle with naturally aspirated and turbocharged gasoline engine
    Autorzy:
    Łoza, Łukasz
    Powiązania:
    https://bibliotekanauki.pl/articles/2097460.pdf
    Data publikacji:
    2020
    Wydawca:
    Polskie Towarzystwo Naukowe Silników Spalinowych
    Tematy:
    vehicle
    vibration
    engine
    downsizing
    fast Fourier transform
    accelerometry
    pojazd
    drgania
    silnik
    szybka transformata Fouriera
    akcelerometria
    Opis:
    In this paper, the author presents a study of vibrations in a passenger vehicle and the possible influence on driver’s body in the process of natural operation. The author describes the dependence of engine size and additional equipment as the possible primary source of the vibration variations and their further propagation in the entire vehicle structure. The analysis was performed on the passenger cars with naturally aspirated and turbocharged gasoline engines. The aim of this study was to verify the level of vibrations in the vehicle structure with these particular engines, especially influence of downsized power unit, during various state of engine operation. The second goal was to examine the vibrations in the specified location related to driver’s body. The measuring method used piezoelectric accelerometers, which were attached to the designated locations in the vehicle and were able to detect variations of the acceleration. The signals were collected as characteristics in the time domain. In order to achieve frequency domain for spectral analyses, the author applied the Fast Fourier Transform (FFT).
    Źródło:
    Combustion Engines; 2020, 59, 2; 19--23
    2300-9896
    2658-1442
    Pojawia się w:
    Combustion Engines
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Measurement of Surface Profile and Surface Roughness of Fibre-Optic Interconnect by Fast Fourier Transform
    Autorzy:
    Lin, C. S.
    Yang, S. W.
    Lin, H. L.
    Li, J. W.
    Powiązania:
    https://bibliotekanauki.pl/articles/221117.pdf
    Data publikacji:
    2017
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    surface profile
    surface roughness
    fibre end-face
    fast Fourier transform
    Opis:
    This study proposes a surface profile and roughness measurement system for a fibre-optic interconnect based on optical interferometry. On the principle of Fizeau interferometer, an interference fringe is formed on the fibre end-face of the fibre-optic interconnect, and the fringe pattern is analysed using the Fast Fourier transform method to reconstruct the surface profile. However, as the obtained surface profile contains some amount of tilt, a rule for estimating this tilt value is developed in this paper. The actual fibre end-face surface profile is obtained by subtracting the estimated tilt amount from the surface profile, as calculated by the Fast Fourier transform method, and the corresponding surface roughness can be determined. The proposed system is characterized by non-contact measurement, and the sample is not coated with a reflector during measurement. According to the experimental results, the difference between the roughness measurement result of an Atomic Force Microscope (AFM) and the measurement result of this system is less than 3 nm.
    Źródło:
    Metrology and Measurement Systems; 2017, 24, 2; 381-390
    0860-8229
    Pojawia się w:
    Metrology and Measurement Systems
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    The possibility of diagnosis EGR systems defects by vibration analysis
    Autorzy:
    Kaźmierczak, A.
    Wróbel, R.
    Powiązania:
    https://bibliotekanauki.pl/articles/244781.pdf
    Data publikacji:
    2008
    Wydawca:
    Instytut Techniczny Wojsk Lotniczych
    Tematy:
    EGR system
    fast Fourier transform
    automotive diagnosis
    vibroacustic analysis
    Opis:
    The Exhaust Gas Recirculation is a popular system of recirculation of the automotive vehicle emission. The principle of working depends on the forcing in the part of outlet gas to the combustion chamber. Majority of the users of automotive vehicles with EGR systems claim that system has negative effect on the performance of the car. Nonetheless, that opinion is subjective, because the generally available research on the subject does not exist. However, EGR system, as the most of automotive vehicle is being subjected to physic's rules - it uses up. The polluted flowing valve of circuit has an influence on stability of engine's work, and what follows on a performance of a car. The authors present a new in - vitro way of diagnosis in automotive vehicle, which depend on detection and measure of vibroacustic vibrations of the diesel engine. It seems that EGR circuit that does not work properly should not have an influence on vibrations generated by an engine. However, authors indicate that this statement is wrong. EGR system has an influence on engine's vibration, what was described in the article. On that way, detection of vibrations must be accomplished with high quality diagnostic systems. Therefore, vibrometric laser scanner Polytec had been used. To achieve full diagnostic results multidimensional vibration's function has been researched, where the torque moment has been used as an extra parameter. Measured vibrations were subjected to digital signal processing like windowing, fast Fourier transform, filtration by finite impulse response. The results of measure and processing perform in form of 3D plots, which indulge in speed estimate of the usefulness of presented method. Moreover authors presents principle of working EGRs' systems of different generations and its evolution.
    Źródło:
    Journal of KONES; 2008, 15, 4; 217-225
    1231-4005
    2354-0133
    Pojawia się w:
    Journal of KONES
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Balance disturbances coefficient as a new value to assess ability to maintain balance on the basis of FFT curves
    Autorzy:
    Jurkojc, J.
    Powiązania:
    https://bibliotekanauki.pl/articles/307349.pdf
    Data publikacji:
    2018
    Wydawca:
    Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
    Tematy:
    równowaga
    stabilografia
    szybka transformacja Fouriera
    balance
    stabilography
    fast Fourier transform
    coefficient
    Opis:
    The aim of this study was to formulate a new balance disturbances coefficient enabling objective balance assessment on the basis of fast Fourier transform curves. The article presents the method of coefficient calculation and possible ways of its interpretation. Methods: 11 healthy participants took part in the experiment. There were four measurements: two in real environment with eyes open and eyes closed as well as two in virtual environment with scenery (surroundings) oscillating with frequency 0.7 Hz and 1.4 Hz. Scenery was displayed by means of the Oculus Rift system, whereas position of centre of pressure was measured with the use of Zebris FDM-S platform. Obtained centre of pressure positions were used to calculate fast Fourier transform, and then balance disturbances coefficient. Results: Comparisons of coefficient values obtained for the whole group and two selected participants were presented in order to explain how to interpret and use the coefficient. For better explanation of coefficient interpretation the most popular time domain stabilometric quantities and fast Fourier transform curves were presented as well. Conclusions: The balance disturbances coefficient makes it possible to quantitatively and objectively determine, on the basis of fast Fourier transform curves, the influence of the oscillating scenery on the tested person as well as show how the overall equilibrium of that person was disturbed.
    Źródło:
    Acta of Bioengineering and Biomechanics; 2018, 20, 1; 143-151
    1509-409X
    2450-6303
    Pojawia się w:
    Acta of Bioengineering and Biomechanics
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Deblurring approach for motion camera combining FFT with α-confidence goal optimization
    Autorzy:
    Huang, Lve
    Wu, Lushen
    Xiao, Wenyan
    Peng, Qingjin
    Powiązania:
    https://bibliotekanauki.pl/articles/174045.pdf
    Data publikacji:
    2020
    Wydawca:
    Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
    Tematy:
    image deblurring
    fast motion camera
    confidence goal optimization
    fast Fourier transform
    high-railway defect detection
    Opis:
    Sharp images ensure success in the object detection and recognition from state-of-art deep learning methods. When there is a fast relative motion between the camera and the object being imaged during exposure, it will necessarily result in blurred images. To deblur the images acquired under the camera motion for high-quality images, a deblurring approach with relatively simple calculation is proposed. An accurate estimation method of point spread function is firstly developed by performing the Fourier transform twice. Artifacts caused by image direct deconvolution are then reduced by predicting the image boundary region, and the deconvolution model is optimized by an α-confidence statistics algorithm based on the greyscale consistency of the image adjacent columns. The proposed deblurring approach is finally carried out on both the synthetic-blurred images and the real-scene images. The experiment results demonstrate that the proposed image deblurring approach outperforms the existing methods for the images that are seriously blurred in direction motion.
    Źródło:
    Optica Applicata; 2020, 50, 2; 185-198
    0078-5466
    1899-7015
    Pojawia się w:
    Optica Applicata
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Determining the weights of a Fourier series neural network on the basis of the multidimensional discrete Fourier transform
    Autorzy:
    Halawa, K.
    Powiązania:
    https://bibliotekanauki.pl/articles/907904.pdf
    Data publikacji:
    2008
    Wydawca:
    Uniwersytet Zielonogórski. Oficyna Wydawnicza
    Tematy:
    sieć neuronowa ortogonalna
    szereg Fouriera
    transformata Fouriera
    aproksymacja
    system nieliniowy
    orthogonal neural networks
    Fourier series
    fast Fourier transform
    approximation
    nonlinear system
    Opis:
    This paper presents a method for training a Fourier series neural network on the basis of the multidimensional discrete Fourier transform. The proposed method is characterized by low computational complexity. The article shows how the method can be used for modelling dynamic systems.
    Źródło:
    International Journal of Applied Mathematics and Computer Science; 2008, 18, 3; 369-375
    1641-876X
    2083-8492
    Pojawia się w:
    International Journal of Applied Mathematics and Computer Science
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Zastosowanie probabilistycznego modelu obliczania niepewności pomiaru przy wzorcowaniu omomierza i woltomierza
    Application of probabilistic model for calculating measurement uncertainty in calibration of ohmmeter and voltmeter
    Autorzy:
    Fotowicz, P.
    Korczyński, M. J.
    Hetman, A.
    Powiązania:
    https://bibliotekanauki.pl/articles/155135.pdf
    Data publikacji:
    2006
    Wydawca:
    Stowarzyszenie Inżynierów i Techników Mechaników Polskich
    Tematy:
    niepewność pomiaru
    wzorcowanie
    szybka transformata Fouriera
    uncertainty measurement
    calibration
    fast Fourier transform
    Opis:
    Przedmiotem niniejszego artykułu jest zagadnienie obliczania niepewności pomiaru przy wzorcowaniu woltomierza i omomierza z wykorzystaniem probabilistycznego modelu opisu matematycznego wielkości mierzonej. Liniowy model pomiaru umożliwia zastosowanie zasady propagacji rozkładów w oparciu o splot wielkości wejściowych. W obliczeniach posłużono się przybliżoną metodą analityczną oraz metoda dokładną z zastosowaniem szybkiej transformaty Fouriera. Obie metody są oryginalnymi opracowaniami autorów.
    The calculation of uncertainties in calibration of voltmeter and ohmmeter calibration based on probabilistic model is presented here. The probabilistic model used for calculation of uncertainties allowed to apply two methods: so called analytical method and FFT method based on Fast Fourier Transform. Both methods are original work of all three co-authors of the paper.
    Źródło:
    Pomiary Automatyka Kontrola; 2006, R. 52, nr 11, 11; 20-24
    0032-4140
    Pojawia się w:
    Pomiary Automatyka Kontrola
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Model identification and update under operation of active noise control systems
    Identyfikacja i uaktualnianie modeli w trakcie pracy układów aktywnego tłumienia hałasu
    Autorzy:
    Figwer, J.
    Powiązania:
    https://bibliotekanauki.pl/articles/151819.pdf
    Data publikacji:
    2003
    Wydawca:
    Stowarzyszenie Inżynierów i Techników Mechaników Polskich
    Tematy:
    układy aktywnego tłumienia hałasu
    tłumienie hałasu
    identyfikacja modeli
    uaktualnianie modeli
    active noise control
    system identification
    adaptive systems
    frequency response
    fast Fourier transform
    Opis:
    In the paper, a new look at on-line electro-acoustic plant model identification and update for feedforward active noise control (ANC) systems under their operation is presented. The problem of on-line electro-acoustic plant model identification under active ANC system is discussed as a closed-loop identification problem with a low signal-to-noise ratio. The feedback is introduced by an adaptation algorithm. Additionally it may be also implied by an acoustic interaction between a control loudspeaker and reference microphone. In ANC literature concerning on-line electro-acoustic plant modelling it is proposed to identify electro-acoustic plant models together with the feedback. It leads to biased and inconsistent identification results. In the paper, an approach to this problem that gives results converging asymptotically to true electro-acoustic plant models is presented.
    W pracy zaprezentowano nowe spojrzenie na problem identyfikacji on-line modeli torów elektroakustycznych w adaptacyjnych kompensacyjnych układach aktywnego tłumienia hałasu (ATH). Problem ten dyskutowany jest jako problem identyfikacji obiektu pracującego w układzie ze sprzężeniem zwrotnym przy niskim stosunku sygnału do szumu. Sprzężenie to wprowadzane jest w układach ATH poprzez algorytm adaptacji. Może być ono również wynikiem akustycznej interakcji głośnika sterującego z mikrofonem błędu. W literaturze poświęconej aktywnemu tłumieniu hałasu proponuje się, by w trakcie pracy układów ATH identyfikować modele torów elektroakustycznych wraz ze wspomnianym sprzężeniem zwrotnym. Otrzymane w ten sposób oceny parametrów modeli torów elektroakustycznych są obciążone. W artykule zaproponowano nową metodę identyfikacji tych modeli. Metoda ta pozwala uzyskać asymptotycznie nieobciążone i zgodne oceny parametrów modeli torów elektroakustycznych.
    Źródło:
    Pomiary Automatyka Kontrola; 2003, R. 49, nr 11, 11; 22-25
    0032-4140
    Pojawia się w:
    Pomiary Automatyka Kontrola
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Multisine Approximation of Multivariate Orthogonal Random Processes
    Autorzy:
    Figwer, J.
    Powiązania:
    https://bibliotekanauki.pl/articles/908295.pdf
    Data publikacji:
    1999
    Wydawca:
    Uniwersytet Zielonogórski. Oficyna Wydawnicza
    Tematy:
    proces stochastyczny
    procesy wielowymarowe
    transformata Fouriera
    simulation random processes
    multivariate orthogonal random processes
    simulated indentification
    multisine random time-series
    fast Fourier transform
    Opis:
    An approach to the synthesis and simulation of wide-sense stationary multivariate orthogonal random processes defined by their power spectral density matrices is presented. The approach is based on approximating the non-parametric power spectral density representation by the periodogram matrix of a multivariate orthogonal multisine random time-series. This periodogram matrix is used to construct the corresponding spectrum of the multivariate orthogonal multisine random time-series (synthesis). Application of the inverse finite discrete Fourier transform to this spectrum results in a multivariate orthogonal multisine random time-series with the predefined periodogram matrix (simulation). The properties of multivariate orthogonal multisine random process approximations obtained in this way are discussed. Attention is paid to asymptotic gaussianess.
    Źródło:
    International Journal of Applied Mathematics and Computer Science; 1999, 9, 2; 401-419
    1641-876X
    2083-8492
    Pojawia się w:
    International Journal of Applied Mathematics and Computer Science
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Diagnostyka lokalnych uszkodzeń zębów kół przekładni przy użyciu szybkiej transformaty Fouriera i logiki rozmytej
    The diagnostic of tooth gears failures by using fast Fourier transform and fuzzy logic
    Autorzy:
    Czech, P.
    Powiązania:
    https://bibliotekanauki.pl/articles/328370.pdf
    Data publikacji:
    2008
    Wydawca:
    Polska Akademia Nauk. Polskie Towarzystwo Diagnostyki Technicznej PAN
    Tematy:
    diagnostyka
    przekładnia zębata
    logika rozmyta
    szybka transformata Fouriera
    diagnostics
    gearboxes
    fuzzy logic
    fast Fourier transform
    Opis:
    W artykule przedstawiono wyniki prób mających na celu budowę klasyfikatora lokalnych uszkodzeń zębów kół przekładni, zbudowanego w oparciu o logikę rozmytą. Obiekt badań stanowiła przekładnia zębata o zębach prostych, pracująca na stanowisku mocy krążącej FZG. Badaniami objęto przekładnie z kołami bez uszkodzeń oraz z lokalnymi uszkodzeniami zębów w postaci pęknięcia u podstawy zęba oraz wykruszenia wierzchołka zęba. Zaproponowano również sposób budowy systemów diagnozujących lokalne uszkodzenia zębów kół. Do tego celu wykorzystano sygnały drganiowe poddane odpowiedniej filtracji oraz przetwarzaniu.
    This article presents the tests results showing the construction of the local damages classifier of the transmission gear teeth, built on the basis of the fuzzy logic. The tested object was the transmission gear with straight teeth, working on the circulating power FZG stand. The tests included the gears with the undamaged teeth and with the locally damaged teeth in the form of the crack root and the chip tip of the tooth. The construction of the systems diagnosing the local damages of the teeth was also proposed. To achieve this aim, the vibration signals which had undergone proper filtration and processing were used.
    Źródło:
    Diagnostyka; 2008, 1(45); 43-52
    1641-6414
    2449-5220
    Pojawia się w:
    Diagnostyka
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Badania oddziaływań drgań pochodzenia komunikacyjnego na budynki mieszkalne i ludzi w aglomeracji warszawskiej
    The research concerning the effects of road traffic and its influence on the flat buildings and people in Warsaw agglomeration
    Autorzy:
    Chyży, T.
    Powiązania:
    https://bibliotekanauki.pl/articles/182831.pdf
    Data publikacji:
    2008
    Wydawca:
    Instytut Techniki Budowlanej
    Tematy:
    aglomeracja warszawska
    drganie komunikacyjne
    budynek mieszkalny
    ruch drogowy
    pomiar
    stanowisko pomiarowe
    szybka transformacja Fouriera
    rozprzestrzenianie drgań
    Warsaw agglomeration
    traffic vibration
    dwelling house
    measurement
    road traffic
    sensors location
    fast Fourier transform
    vibration propagation
    Opis:
    Zaprezentowano wyniki badań poziomów drgań w budynkach mieszkalnych, generowanych przez ruch taboru kołowego. Ocenę poziomów drgań odniesiono do pasm 1/3-oktawowych i naniesiono na nomogramy dla analizowanego kierunku drgań zalecone w PN-88/B--02171 oraz instrukcji ITB nr 348/98, względem których dokonano oceny szkodliwości tych drgań. Podano również wyniki badań propagacji drgań źródło-budynek oraz zaprezentowano koncepcję metody odwzorowania dowolnego rodzaju oddziaływań transmitowanych przez podłoże gruntowe.
    The development of Warsaw agglomeration and the increase of transported article and persons, causes also the worsening of road surface conditions. It affects the increase of dynamic effects propagated to the environment in the form of noise and vibrations of the ground. These loads are transfered to the buildings situated near communication tracks, enlarging the occupants discomfort and sometimes causing construction damage. In this paper the following problems have presented and discussed: • the results of measurements of the vibrations levels on buildings, generated by road traffic; the measurement points have been localized on the region of the capital town of Warsaw and in neighbouring towns; the results were presented in the 1/3 octave strips (tierce) and were put on the special nomograms • the results of measurements of the vibrations propagation on the way from source (road traffic) to buildings. These results were presented in narrow frequencies strips (5 Hz) • the conception of the new method for reconstruction of possible vibrations, which have affected the buildings in the past - the "reconstruction method".
    Źródło:
    Prace Instytutu Techniki Budowlanej; 2008, R. 37, nr 1, 1; 19-41
    0138-0796
    Pojawia się w:
    Prace Instytutu Techniki Budowlanej
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    High Performance DIF-FFT Using Dissimilar Partitioned LUT Based Distributed Arithmetic
    Autorzy:
    Cheepurupalli, Kusma Kumari
    Charan, Muntha
    Rao, Jammu Bhaskara
    Noor, Mahammad S.
    Powiązania:
    https://bibliotekanauki.pl/articles/2055270.pdf
    Data publikacji:
    2021
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    fast Fourier transform
    adders
    distributed arithmetic
    DSP
    Opis:
    Real-time data processing systems utilize Digital Signal Processing (DSP) functions as the base modules. Most of the DSP functions involve the implementation of Fast Fourier Transform (FFT) to convert the signals from one domain to another domain. The major bottleneck of Decimation in frequency - Fast Fourier Transform (DIF-FFT) implementation lies in using a number of Multipliers. Distributed arithmetic (DA) is considered as one of the efficient techniques to implement DIF-FFT. In this approach, the multipliers are not used. The proposed technique exploits the very advantage of the look-up table by storing the Twiddle factors, thereby avoiding the multipliers required in the butterfly structure. DIF-FFT using Distributed Arithmetic (DIF-FFT DA) models, with different adders such as Ripple carry adder (RCA), Carry-lookahead adder (CLA), and Sklansky prefix graph adder, are proposed in this paper. The three proposed models are synthesized using Cadence 6.1 EDA tools with a 45nm CMOS technology. Compared to the traditional method, it is observed that the area is improved by 53.11%, 53.35%, and 50.15%, power is improved by 42.31%, 42.52%, and 40.39%, and delay is improved by 45.26%, 45.42%, 41.80%, respectively.
    Źródło:
    International Journal of Electronics and Telecommunications; 2021, 67, 4; 631--637
    2300-1933
    Pojawia się w:
    International Journal of Electronics and Telecommunications
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
      Wyświetlanie 1-28 z 28

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