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Wyszukujesz frazę "fast transform" wg kryterium: Temat


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
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:
Classification of Seizure Types Using Random Forest Classifier
Autorzy:
Basri, Ashjan
Arif, Muhammad
Powiązania:
https://bibliotekanauki.pl/articles/2123290.pdf
Data publikacji:
2021
Wydawca:
Stowarzyszenie Inżynierów i Techników Mechaników Polskich
Tematy:
EEG
fast fourier transform
seizure
random forest
Opis:
Epilepsy is one of the most common mental disorders in the world, affecting 65 million people. The prevalence in Arab countries of Epilepsy is estimated at 174 per 100,000 individuals, and in Saudi Arabia is 6.54 per 1,000 individuals. Epilepsy seizures have different types, and each patient needs to have a treatment plan according to the seizure type. Hence, accurate classification of seizure type is an essential part of diagnosing and treating epileptic patients. In this paper, features based on fast Fourier transform from EEG montages are used to classify different types of seizures. Since the distribution of classes is not uniform and the dataset suffers from severe imbalance. Various algorithms are used to under-sample the majority class and over-sample the minority classes. Random forest classifier produced classification accuracy of 96% to differentiate three types of seizures from the healthy EEG reading.
Źródło:
Advances in Science and Technology. Research Journal; 2021, 15, 3; 167--178
2299-8624
Pojawia się w:
Advances in Science and Technology. Research Journal
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Autofocusing with the help of orthogonal series transforms
Autorzy:
Śliwiński, P.
Powiązania:
https://bibliotekanauki.pl/articles/226176.pdf
Data publikacji:
2010
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
autofocusing
discrete orthogonal systems
fast orthogonal transform
transform coding
Opis:
An autofocus algorithm employing orthogonal series expansions is proposed. Several instances of the generic algorithm, based on discrete trigonometric, polynomial and wavelet series, are reviewed. The algorithms are easy to implement in the transform coders used in digital cameras. Formal analysis of the algorithm properties is illustrated in experiments. Some practical issues are also discussed.
Źródło:
International Journal of Electronics and Telecommunications; 2010, 56, 1; 33-39
2300-1933
Pojawia się w:
International Journal of Electronics and Telecommunications
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
On implementation of FFT processor in XILINX FPGA using high-level synthesis
Autorzy:
Smyk, Robert
Czyżak, Maciej
Powiązania:
https://bibliotekanauki.pl/articles/377926.pdf
Data publikacji:
2020
Wydawca:
Politechnika Poznańska. Wydawnictwo Politechniki Poznańskiej
Tematy:
Fast Fourier Transform Processor
FPGA
high-level synthesis
Opis:
The paper presents results of the high level synthesis of an 1024-point radix-2 FFT processors in Xilinx Vivado FPGA environment. The use of various directives controlling the synthesis process is examined. The results indicate that using the proper set of directives the latency of the processor can be reduced by 95% from about 35k for the default parameters to 1.5k cycles after optimizations.
Źródło:
Poznan University of Technology Academic Journals. Electrical Engineering; 2020, 104; 17-33
1897-0737
Pojawia się w:
Poznan University of Technology Academic Journals. Electrical Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
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:
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:
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:
Experimental Comparative Investigations to Evaluate Cavitation Conditions within a Centrifugal Pump Based on Vibration and Acoustic Analyses Techniques
Autorzy:
Al-Obaidi, Ahmed Ramadhan
Powiązania:
https://bibliotekanauki.pl/articles/177056.pdf
Data publikacji:
2020
Wydawca:
Polska Akademia Nauk. Czasopisma i Monografie PAN
Tematy:
centrifugal pump
cavitation
Fast Fourier Transform
vibration
acoustic
normalise features
Opis:
Cavitation is an essential problem that occurs in all kinds of pumps. This cavitation contributes highly towards the deterioration in the performance of the pump. In industrial applications, it is very vital to detect and decrease the effect of the cavitation in pumps. Using different techniques to analysis and diagnose cavitation leads to increase in the reliability of cavitation detection. The use of various techniques such as vibration and acoustic analyses can provide a more robust detection of cavitation within the pump. In this work therefore, focus is put on detecting and diagnosing the cavitation phenomenon within a centrifugal pump using vibration and acoustic techniques. The results obtained from vibration and acoustic signals in time and frequency domains were analysed in order to achieve better understanding regarding detection of cavitation within a pump. The effect of different operating conditions related to the cavitation was investigated in this work using different statistical features in time domain analysis (TDA). Moreover, Fast Fourier Transform (FFT) technique for frequency domain analysis (FDA) was also applied. Furthermore, the comparison and evaluation system among different techniques to find an adequate technique incorporating for accuracy and to increase the reliability of detection and diagnosing different levels of cavitation within a centrifugal pump were also investigated.
Źródło:
Archives of Acoustics; 2020, 45, 3; 541-556
0137-5075
Pojawia się w:
Archives of Acoustics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
A Comparative Analysis of Evolutionary Algorithms for Synthesis of Scanned Linear Array of Mutually Coupled Parallel Dipole Antennas
Autorzy:
Patidar, H.
Mahanti, G. K.
Muralidharan, R.
Powiązania:
https://bibliotekanauki.pl/articles/227212.pdf
Data publikacji:
2017
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
antenna array
comparative analysis
evolutionary algorithms
inverse fast Fourier transform
scanning
Opis:
This paper presents a comparative analysis of three evolutionary algorithms, namely, Backtracking Search Algorithm, Cuckoo Search Algorithm and Artificial Bee Colony Algorithms for synthesis of a scanned linear array of uniformly spaced parallel half wavelength dipole antennas. Here, antenna parameters, namely Side Lobe Level, reflection coefficient and wide null depth are taken into consideration for comparison between algorithms. In addition to it, statistical parameters, namely best fitness value, mean and standard deviation of the fitness values obtained from algorithms are compared. Mutual coupling that exists among the antenna elements is included in obtaining radiation patterns and the self-impedances along with the mutual impedances are calculated by induced Electro-Motive Force method. Two different examples are shown in this paper to validate the effectiveness of the utilized approach. Although, this approach is applied to a linear array of dipole antennas; this can be utilized for other array geometries as well.
Źródło:
International Journal of Electronics and Telecommunications; 2017, 63, 2; 151-157
2300-1933
Pojawia się w:
International Journal of Electronics and Telecommunications
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
VMD and CNN-Based Classification Model for Infrasound Signal
Autorzy:
Lu, Quanbo
Li, Mei
Powiązania:
https://bibliotekanauki.pl/articles/31339812.pdf
Data publikacji:
2023
Wydawca:
Polska Akademia Nauk. Czasopisma i Monografie PAN
Tematy:
infrasound signal
variational mode decomposition
convolutional neural network
Fast Fourier Transform
Opis:
Infrasound signal classification is vital in geological hazard monitoring systems. The traditional classification approach extracts the features and classifies the infrasound events. However, due to the manual feature extraction, its classification performance is not satisfactory. To deal with this problem, this paper presents a classification model based on variational mode decomposition (VMD) and convolutional neural network (CNN). Firstly, the infrasound signal is processed by VMD to eliminate the noise. Then fast Fourier transform (FFT) is applied to convert the reconstructed signal into a frequency domain image. Finally, a CNN model is established to automatically extract the features and classify the infrasound signals. The experimental results show that the classification accuracy of the proposed classification model is higher than the other model by nearly 5%. Therefore, the proposed approach has excellent robustness under noisy environments and huge potential in geophysical monitoring.
Źródło:
Archives of Acoustics; 2023, 48, 3; 403-412
0137-5075
Pojawia się w:
Archives of Acoustics
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:
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:
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:
Radial internal clearance analysis in ball bearings
Autorzy:
Ambrożkiewicz, Bartłomiej
Syta, Arkadiusz
Meier, Nicolas
Litak, Grzegorz
Georgiadis, Anthimos
Powiązania:
https://bibliotekanauki.pl/articles/1841795.pdf
Data publikacji:
2021
Wydawca:
Polska Akademia Nauk. Polskie Naukowo-Techniczne Towarzystwo Eksploatacyjne PAN
Tematy:
ball bearings
radial internal clearance
statistical analysis
recurrence
fast fourier transform
continuous wavelet transform
Opis:
Radial internal clearance (RIC) is one of the most important parameters influencing on rolling bearing exploitation in mechanical systems. Lifetime of rotary machines strongly depends on a condition of applied rolling elements, thus a study on applied clearance is very important in terms of maintenance and reliability. This paper proposes, a novel approach of studying RIC, based on a nonlinear dynamics method called recurrences. The results are confronted with standard analyses, i.e. statistical condition indicators, Fast Fourier Transform and Continuous Wavelet Transform. The application of the mentioned methods allowed us to find the optimal radial clearance for operating bearings. To ensure precise measurements of the clearance, an automated setup for RIC measurements is applied and next mounted in a plummer block and tested to finally measure vibration acceleration. The proposed methods are useful for a condition monitoring and lifetime prediction of bearings or bearing-based systems in which a proper value of radial clearance is crucial.
Źródło:
Eksploatacja i Niezawodność; 2021, 23, 1; 42-54
1507-2711
Pojawia się w:
Eksploatacja i Niezawodność
Dostawca treści:
Biblioteka Nauki
Artykuł

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