Background: In myocardial perfusion SPECT imaging, images are degraded by photon attenuation, the distance-dependent collimator, detector response and photons scatter. Filters greatly affect quality of nuclear medicine images Materials and Methods: A phantom simulating heart left ventricle was built. About 1mCi of 99mTc was injected into the phantom. Images were taken from this phantom. Some fi...

odor emission is a common environmental problem in septic tank. the feasibility of using trickling filter to eliminate the malodorous gases from the septic tank was studied. a trickling filter is set up at the outlet of the waste gases of the septic tank, which was attached to the university's cafeteria. in this investigation, the trickling filter system was used, measuring the hydrogen sulfide...

Radio Frequency Interferences (RFI), such as strong Continuous Wave (CWI), can influence the Quality of Service (QoS) communications, increasing Bit Error Rate (BER) and decreasing Signal-to-Noise Ratio (SNR) in any wireless transmission, including a Digital Video Broadcasting (DVB-S2) receiver. Therefore, this paper presents an algorithm for detecting mitigating Multi-tone Interference (MCWI) ...

A second order voltage mode tunable universal filter is presented. The voltage mode filter is based on dual output second generation current controlled current conveyor (DOCCCII). The filter is capable of realizing high pass (HP), low pass (LP), band pass (BP), notch pass (NP) and all pass (AP) responses in voltage mode (VM). The filter employs only two capacitors and hence enjoys minimum compo...

Much attention has recently been given to the construction of signaladapted orthonormal filter banks designed to optimize a particular objective function such as coding gain or a multiresolution criterion. For certain classes of filter banks, the optimum solution is a principal component filter bank (PCFB), which is simultaneously optimal for several objectives including the ones mentioned abov...

The aim of this paper is to present a comparison of some popular methods for online harmonic estimation. The wellknown methods Descrete Fourier Ttransform (DFT), Enhanced Phase Locked Loop (EPLL), Adaptive Notch Filter (ANF) and method based on Extended Kalman Filter (EKF) are simulated and compared. The methods are compared in critical phases, such as the fast change of harmonic amplitudes and...

A new high input impedance voltage-mode universal biquadratic filter with three input terminals and five output terminals is presented. The proposed circuit uses three plus-type differential difference current conveyors, two grounded resistors and two grounded capacitors. The proposed circuit can realize all the standard filter functions: lowpass, bandpass, highpass, notch and allpass, without ...