There are two types of digital filters including Infinite Impulse Response (IIR) and Finite Impulse Response (FIR). IIR filters attract more attention as they can decrease the filter order significantly compared to FIR filters. Owing to multi-modal error surface, simple powerful optimization techniques should be utilized in designing IIR digital filters to avoid local minimum. Imperialist compe...

Background: The aim of present study was to analyze the effectiveness of electron filters in the Telecobalt radiotherapy treatment by simulation technique.  Materials and Methods: The BEAMnrc Monte Carlo code was used to simulate the electron filters of thickness of 0.5 gm/cm2 below the trimmer bar for 35 × 35 cm2 field size in Theratron Equinox-80 telecobalt unit. The electron filters were mad...

In this paper, we propose a theoretical model to simulate microbial growth on contaminated air filters and entrainment of bioaerosols from the filters to an indoor environment. Air filter filtration and antimicrobial efficiencies, and effects of dust particles on these efficiencies, were evaluated. The number of bioaerosols downstream of the filter could be characterized according to three phas...

in this article, the effect of cells' radius on the behavior of wavelength switching optical filter andthe effect of the radius of the optical filters' key characteristics such as wavelength resonance onan optical filter based on photonic crystals, have been investigated. currently, the most commonapplied mechanism for designing optical filter based on photonic crystals is using twomechanisms s...

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...

introduction one of the most important pre-processing steps in optical coherence tomography (oct) is reducing speckle noise, resulting from multiple scattering of tissues, which degrades the quality of oct images. materials and methods the present study focused on speckle noise reduction and edge detection techniques. statistical filters with different masks and noise variances were applied on ...

one of the main problems in micro irrigation system is inappropriate combination and in some cases inappropriate performance of filters and sand tanks in central control systems which cause reduction in efficiency of system and increasing of operating costs. this study evaluates affect the amount of algae on the performance of disc filters sand tank in research farm deputy of soil and water and...

Edge detection and edge enhancement techniques play an essential role in interpreting potential field data. This paper describes the application of various edge detection techniques to gravity data in order to delineate the edges of subsurface structures. The edge detection methods comprise analytic signal, total horizontal derivative (THDR), theta angle, tilt angle, hyperbolic of tilt angle (H...