Improvements of Edges Detecting and Diffraction Field Computing in GRECO
Graphical Electromagnetic Computing(GRECO)is one of the valuable method for computing the radar cross section(RCS)of complex radar target in high frequency region.But there are some shortages of edges detecting method in original GRECO literature ,a new method of collecting the edge pixels and wedge parameters is presented in this paper.Since an expression of edge diffraction field in the literature is in error,the error correcting formulas are derived by using method of equivalent edge currents(MEC)and physical theory of diffraction(PTD).Finally,the total RCS expression is given by using physical optics(PO)and PTD method.The computing results are in close agreement with the measured data.
Study Design.A meta-analysis.Objective.The aim of this study was to compare the diagnostic accuracies of F-18 fluorodeoxyglucose (F-18 FDG) positron emission tomography (PET) and magnetic resonance imaging (MRI) for the detection of spondylodiscitis through a meta-analysis.Summary of Background Data