Introduction:Low-pass filters eliminate noise, and accordingly improve the quality of filtered back-projection (FBP) in the reconstruction of single photon emission computed tomography (SPECT) images. This study aimed at selection of an optimum low-pass filter for FBP reconstruction of SPECT images of small structures. Material and Methods:Sp...

Filter design specifications can be manifest in all manner of necessity, whether they are high-pass, low-pass, band-pass, or stop-band filters. In addition, the parameters for such filters are defined for a very specific application. A design for a lowpass filter with a pass-band of 2k Hz and a stop-band of 4k will be discussed. The further properties of the filter are to allow for a 48 dB drop...

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...

Introduction Non-invasive Fluorescent Reflectance Imaging (FRI) is used for accessing physiological and molecular processes in biological media. The aim of this article is to separate the overlapping emission spectra of quantum dots within tissue-equivalent phantom using SVD, Jacobi SVD, and NMF methods in the FRI mode. Materials and Methods In this article, a tissue-like phantom and an optical...

This article proposes an alternative method for designing miniature waveguide filters based on locally resonant metamaterials. Implementation of ultra-small metamaterial (metafilters) using the subwavelength direction mechanism in hollow waveguides loaded with small resonators. In particular, composite pin are used, constructed from a metal tube set pins that spaced over deep distances. such st...