Using the sampled data of a desired pattern is a common technique in pattern synthesizing of array factor (AF) of antenna arrays. Based on the obtained data matrix, Least Square Method (LSM) is used to calculate the exciting coefficient of array elements. The most important parameter, which involves the accuracy and complexity of calculation, is the sampling rate of the desired pattern. Classic...

Parallel imaging technique using localized gradient (PatLoc) uses the combination of surface gradient coils and an RF receiver array to further improve the efficiency of gradients and to reduce the peripheral nerve stimulation hazard [1]. PatLoc is a generalization of non-Cartesian gradient encoding, such as MR-encephalography [2] or inverse imaging [3]. The imaging and reconstruction algorithm...

in this paper, we generalize a theorem of shao [12] by assuming that is a sequence of linear negatively dependent random variables. also, we extend some theorems of chao [6] and thrum [14]. it is shown by an elementary method that for linear negatively dependent identically random variables with finite -th absolute moment the weighted sums converge to zero as where and is an array of real numbe...

This paper presents a low-cost compact planar microstrip-fed monopole antenna and its four-element array design for ultra-wideband (UWB) wireless communication and target detection applications, respectively, operating in the frequency span of 3 GHz to 11 GHz. A prototype was fabricated and then measured based on optimal parameters. The results of reflection coefficient (S11) and radiation patt...

Introduction: Image quality and accuracy of in vivo activity quantification in SPECT are affected by collimator penetration and scatter components, especially in high energy imaging. These phenomena highly depend on the collimator characteristic and photon energy. The presence of penetrated and scattered photons from collimator in SPECT images degrades spatial resolution, contr...

This research aims to study testis and epididymis of dry land goat (Capra hircus) on B-mode ultrasound imaging. Twelve adult local male goats were examined normal testes ultrasonic appearances. real time scanner with a 7.5 MHz, linear array transducer was used evaluate the echotexture testicular parenchyma, mediastinum epididymis. The parenchyma represented uniformly homogenous moderately echog...

Introduction: Non-linear local gradients have been introduced for high-magnetic fields to alleviate problems arising from fast gradient switching and resulting peripheral nerve stimulation [1]. This work is focused on the implementation of a selfconstructed four-channel phased-array coil for multi-parallel PatLoc imaging to study the non-linear geometry of these fields under realistic condition...

Monte Carlo Method is used to simulate a double layer gadolinium-amorphous silicon thermal neutron detector. The detector fabricated in pixel array configuration has various applications including neutron imaging. According to the simulation results, a detector consisting of a gadolinium (Gd) film with thickness of 2-4 ~m, sandwiched properly with two layers of sufficiently thick (-30 ?µm) hydr...