Fourier transform Research Papers - Academia.edu (original) (raw)

Abstract—In Earth observation programs there is a need of passive low frequency (L-band) measurements to monitor soil moisture and ocean salinity with high spatial resolution 10–20 Km, a radiometric resolution of 1K and a revisit time of... more

Abstract—In Earth observation programs there is a need of passive low frequency (L-band) measurements to monitor soil moisture and ocean salinity with high spatial resolution 10–20 Km, a radiometric resolution of 1K and a revisit time of 1–3 days [1]. Compared to total power radiometers ...

Tsallis statistics (or q-statistics) in nonextensive statistical mechanics is a one-parameter description of correlated states. In this paper we use a translated entropic index: 1−qtoq1 - q \to q1−qtoq . The essence of this translation is to... more

Tsallis statistics (or q-statistics) in nonextensive statistical mechanics is a one-parameter description of correlated states. In this paper we use a translated entropic index: 1−qtoq1 - q \to q1−qtoq . The essence of this translation is to improve the mathematical symmetry of the q-algebra and make q directly proportional to the nonlinear coupling. A conjugate transformation is defined $\hat q

Visual Servoing is generally contained of control and feature tracking. Study of previous methods shows that no attempt has been made to optimize these two parts together. In kernel based visual servoing method, the main objective is to... more

Visual Servoing is generally contained of control and feature tracking. Study of previous methods shows that no attempt has been made to optimize these two parts together. In kernel based visual servoing method, the main objective is to combine and optimize these two parts together and to make an entire control loop. This main target is accomplished by using Lyapanov theory. A Lyapanov candidate function is formed based on kernel definition such that the Lyapanov stability can be verified. The implementation is done in four degrees of freedom and Fourier transform is used for decomposition of the rotation and scale directions from 2D translation. In the present study, a new method in scale and rotation correction is presented. Log-Polar Transform is used instead of Fourier transform for these two degrees of freedom. Tracking in four degrees of freedom is synthesized to show the visual tracking of an unmarked object. Comparison between Log-Polar transform and Fourier transform shows the advantages of the presented method. KBVS based on Log-Polar transform proposed in this paper, because of its robustness, speed and featureless properties.

Filter banks with fixed time-frequency resolution, such as the Short-Time Fourier Transform (STFT), are a common tool for many audio analysis and processing applications allowing effective implementation via the Fast Fourier Transform... more

Filter banks with fixed time-frequency resolution, such as the Short-Time Fourier Transform (STFT), are a common tool for many audio analysis and processing applications allowing effective implementation via the Fast Fourier Transform (FFT). The fixed time-frequency resolution of the STFT can lead to the undesirable smearing of events in both time and frequency. In this paper, we suggest adaptively varying STFT time-frequency resolution in order to reduce filter bank-specific artifacts while retaining adequate frequency resolution. Several strategies for systematic adaptation of time-frequency resolution are proposed. The introduced approach is demonstrated as applied to spectrogram displays, noise reduction, and spectral effects processing.

Chitosan films obtained by dry phase inversion were prepared from an aqueous solution of chitosan in acetic acid. The films, of thickness less than 20 μm, were transparent, very flexible and had smooth surfaces. Increasing the film... more

Chitosan films obtained by dry phase inversion were prepared from an aqueous solution of chitosan in acetic acid. The films, of thickness less than 20 μm, were transparent, very flexible and had smooth surfaces. Increasing the film thickness induced an increase of the internal tensions and the consequent formation of a rough surface. Structural investigations by X-ray diffraction and Fourier transform IR analysis, showed that the chitosan films, as prepared, are amorphous. Further annealing to evaporate acetic acid and water traces, changed the amorphous phase into a more ordered phase, characterized by diffraction peaks at 2θ values of 9, 17, 20 and 23 degrees. Thermal investigations by TG, DTG, and DTA revealed that the decomposition of the chitosan films as prepared proceeds in two stages, starting from 180°C and 540°C.

A new optical method capable of measuring out-of-plane deformations of rotating objects based on the Fourier transform phase decoding technique is presented. Digital holography is used to test the method, which digitally derotates one of... more

A new optical method capable of measuring out-of-plane deformations of rotating objects based on the Fourier transform phase decoding technique is presented. Digital holography is used to test the method, which digitally derotates one of the holograms at its phase reconstruction stage to accurately remove object rotation fringes, uniquely rendering phase maps that quantitatively show the out-of-plane deformation. Commonly, object

Wireline transceivers for high-speed data transmission through backplane and ethernet cables are important applications for microelectronic and nanoelectronic CMOS technologies. Although many circuit simulators provide correct... more

Wireline transceivers for high-speed data transmission through backplane and ethernet cables are important applications for microelectronic and nanoelectronic CMOS technologies. Although many circuit simulators provide correct system-level and transistor-level simulations, they usually fail to give correct results for many highly lossy or/and highly dispersive channels. This paper discusses the advanced simulator that we developed. It can give correct simulation results

an emotion is a mental and physiological state associated with a wide variety of feelings, thoughts, and behavior. Emotions are subjective experiences, or experienced from an individual point of view. Emotion is often associated with... more

an emotion is a mental and physiological state associated with a wide variety of feelings, thoughts, and behavior. Emotions are subjective experiences, or experienced from an individual point of view. Emotion is often associated with mood, temperament, personality, and disposition. Hence, in this paper method for detection of human emotions is discussed based on the acoustic features like pitch, energy etc. The proposed system is using the traditional MFCC approach [2] and then using nearest neighbor algorithm for the classification. Emotions has been classified separately for male and female based on the fact male and female voice has altogether different range [1][4] so MFCC varies considerably for the two. Keywords— Emotion Recognition from Speech, Fourier Transform, MelFilterBank, MFCC, Modern MFCC Approach, Nearest Neighbor Algorithm

A new dynamic harmonic estimator is presented as an extension of the fast Fourier transform (FFT), which assumes a fluctuating complex envelope at each harmonic. This estimator is able to estimate harmonics that are time varying inside... more

A new dynamic harmonic estimator is presented as an extension of the fast Fourier transform (FFT), which assumes a fluctuating complex envelope at each harmonic. This estimator is able to estimate harmonics that are time varying inside the obser- vation window. The extension receives the name "Taylor-Fourier transform (TFT)" since it is based on the McLaurin series expan- sion of

Abstract—The diffraction of E-polarized plane waves by a tandem impedance,slit waveguide is investigated rigorously by using the Fourier transform technique in conjunction with the Mode Matching method. This mixed method,of formulation... more

Abstract—The diffraction of E-polarized plane waves by a tandem impedance,slit waveguide is investigated rigorously by using the Fourier transform technique in conjunction with the Mode Matching method. This mixed method,of formulation gives rise to a scalar Wiener-Hopf equation of the second kind,the solution of which contains infinitely many constants satisfying an infinite system of linear algebraic equations. A numerical solution