This paper presents a new whole-body averaged specific absorption rate (SAR) estimation method based on the cylindrical fields scanning technique. The aim of this study is to achieve experimentally an estimation of whole-body averaged SAR in human models due to plane wave exposure using the radiation-field scanning technique. In this paper, the validity of the proposed methods is investigated u...

Parallel transmission has gained considerable interest during the last few years [1,2]. The use of multiple individual RF transmit coils have been introduced to overcome B1 homogeneity limitations and to improve multi-dimensional RF pulses by shortening their duration. Of special concern in all these transmit applications is the specific absorption rate (SAR), which has to be kept below certain...

shimming. Right: 10gm average RF absorption or SAR for H(1)-(4) for the same B1+ shimming, and mean B1+ of 2.5uT in the brain. Table 1 shows the stats on B1+ and sample SAR variation across subjects for the same B1+ shimming amplitudes and phases. The homogeneity, SAR ave and peak changes were <10 % across the 4 head models H(1)-(4). Figure 1 The Tx array tuning (Smith Chart) on 3 volunteers (d...

The purpose of this study is to establish a whole-body averaged specific absorption rate (WB-SAR) experimental estimation method using the total power absorbed by humans; a cylindrical-external field scanning technique is used to measure the radiated RF (radiofrequency) power. This technique is adopted with the goal of simplifying the exposure dosimetry of humans of different postures and/or si...

In this study a methodological approach for measuring temperature and local absorption rate (SAR) on thin metallic structures, such as pacemaker (PM) leads, is provided. First preliminary experiments were performed to evaluate the error in temperature and SAR measurements made by fluoroptic temperature probes when the temperature probe is in different contact configuration with the PM lead tip....

INTRODUCTION Many wireless systems are more and more present in daily life. More than 5 billions of people over the world are nowadays using devices emitting electromagnetic fields. This paper presents an analysis of the specific absorption rate (SAR) induced by an incident EM plane wave in different fetuses embedded in a homogeneous women model. Moreover, the influence of this homogeneity on t...

The purpose of this paper is to calculate the specific absorption rate (SAR) reduction in muscle cube with metamaterial attachment. The finite-difference time-domain (FDTD) method has been used to evaluate the SAR in a realistic anatomically based model of the muscle cube. We design the single negative metamaterials from periodic arrangement of split ring resonators (SRRS). By properly designin...

| Speckle noise is an inherent property of SAR images. The discrete wavelet transform results in sub-band decompositions of SAR images which have Laplacian point statistics. We propose a Bayesian estimator to perform speckle reduction. We evaluate the speckle reduction results using two measurements: standarddeviation-to-mean ratio and target-to-clutter ratio. We show that good speckle reductio...

soil salinity is one of the problems threatening agricultural lands. parts of this phenomenon are related to geologic formations and saltpans, while some major factors are resulted from irrelevant agricultural activities, issue of irrigation, and improper cultivation systems which lead to increase in soil salinity. to avoid such consequences that would end up with ecosystem degradation, suitabl...

This study analyzes the main parameters that should influence the specific absorption rate (SAR) in children's heads. The evolution of their head shape and the growth of specific parameters, such as the skull thickness, are analyzed. The influence of these parameters on the radio frequency (RF) exposure of children's head is studied. The SAR over 1 g in specific tissue is assessed in different ...