In order to improve the time-frequency resolutions of short-time fractional Fourier transform, adaptive short-time fractional Fourier transform (ASTFRFT) method is used in this paper. The optimal order of ASTFRFT is given by maximizing kurtosis of signals in fractional domain, where the window width of ASTFRFT is searched by the maximal Shannon entropy of timefrequency distribution. Short-time ...

introduction: poor sensitivity and poor signal to noise ratio because of low injected thallium dose and presence of scattered photons are the main problems in using thallium in scintigraphic imaging of the heart. scattered photons are the main cause of degrading the contrast and resolution in spect imaging that result in error in quantification. thallium decay is very complicated and photons ar...

BACKGROUND To explore the diagnostic method in assessing the malignancy of pulmonary adenocarcinoma characterized by ground glass opacities (GGO) on computed tomography (CT). METHODS Preoperative CT data for preinvasive and invasive lung adenocarcinomas were analyzed retrospectively. GGO lesions that were detected on lung windows but absent using the mediastinal window were subject to adjustm...

Energy concentration of the S-transform in the time-frequency domain has been addressed in this paper by optimizing the width of the window function used. A new scheme is developed and referred to as a window width optimized S-transform. Two optimization schemes have been proposed, one for a constant window width, the other for time-varying window width. The former is intended for signals with ...

Metrizamide computed tomography (CT) of the spine allows evaluation of the contents and measurement of the size of intracanalicular structures. The relative size (linear and area measurements) of spinal structures can be changed by varying imaging factors or the density of intrathecal contrast material. Two phantoms, one consisting of rods embedded in a plastic cylinder and the other of a verte...

K. Matsuo, E. T. Bagarinao, T. Iidaka, A. Takeda, and T. Nakai Dept. Psychology, National Taiwan University, Taipei, Taipei, Taiwan, Neuroscience Research Institute, National Institute of Advanced Industrial Science and Technology, Tsukuba, Ibaraki, Japan, Dept. Psychiatry, Nagoya University, Nagoya, Aichi, Japan, Ministry of Health, Labour and Welfare, Chiyodaku, Tokyo, Japan, Dept. Gerontechn...

this paper presents a novel control approach used in shunt active power filter based on variable structure control combined with random pwm technique (rvsc) that provides robust, fast, and more favorable performance for active power filter. this control strategy is compared with two other strategies to show the effectiveness of the introduced methods; pulse width modulated proportional-integral...