Research Article
A Study on the Use of Compound and Extracted Models in
the High Frequency Electromagnetic Exposure Assessment
Mario CvetkoviT,
1
Hrvoje Dodig,
2
and Dragan Poljak
1
1
Faculty of Electrical Engineering, Mechanical Engineering and Naval Architecture, University of Split,
R. Boˇ skovi´ ca 32, 21000 Split, Croatia
2
Faculty of Maritime Studies, University of Split, R. Boˇ skovi´ ca 37, 21000 Split, Croatia
Correspondence should be addressed to Mario Cvetkovi´ c; mcvetkov@fesb.hr
Received 12 July 2017; Accepted 12 October 2017; Published 26 November 2017
Academic Editor: Peter Dabnichki
Copyright © 2017 Mario Cvetkovi´ c et al. Tis is an open access article distributed under the Creative Commons Attribution License,
which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
Te paper presents the numerical results for the induced electric feld in the various models of the human eye and the head. Te
comparison between the extracted or the single organ models and the compound organ models placed inside realistic head models
obtained from the magnetic resonance imaging scans is presented. Te numerical results for several frequencies and polarizations
of the incident electromagnetic (EM) plane wave are obtained using the hybrid fnite element method/boundary element method
(FEM/BEM) formulation and the surface integral equation (SIE) based formulation featuring the use of method of moments,
respectively. Although some previous analysis showed the similar distribution of the induced electric feld along the pupillary
axis obtained in both eye models, this study showed this not to be the case in general. Te analysis showed that the compound
eye model is much more suitable when taking into account the polarization of the incident EM wave. Te numerical results for the
brain models showed much better agreement in the maximum values and distributions of the induced surface feld between detailed
models, while homogeneous brain model showed better agreement with the compound model in the distribution along selected
sagittal axis points. Te analysis could provide some helpful insights when carrying out the dosimetric analysis of the human eye
and the head/brain exposed to high frequency EM radiation.
1. Introduction
Te electromagnetic (EM) felds generated by the various
wireless communication equipment such as mobile phones
and base station antennas have increased the concern among
the general population related to the possible harmful efects.
As the established biological efect of high frequency (HF)
electromagnetic felds is tissue heating, the assessment of this
HF exposure is based on determining the specifc absorption
rate (SAR) that is related to the electric feld induced in the
tissue. Te HF exposure assessment is particularly important
in the case of human eye and brain since experimental mea-
surement in healthy humans is very difcult if not impossible.
Te solution to this is the use of the computational models
and the related numerical solutions as a tool for assessment
of HF exposure [1–3].
Te computational models employed for this particular
type of assessment can be classifed as realistic models of the
human body (or particular organs of interest) based on the
magnetic resonance imaging (MRI) (e.g. [4]) or the simplifed
models, computationally much less demanding but failing to
provide accurate results in most of the exposure scenarios [5].
Te detailed models of the complete human body are
nowadays readily available (e.g., [6, 7]); however, the detailed
human body model puts the signifcant burden in the
computational model preparation at the same time putting
strain on the available computational resources. In addition
to this, there are cases when only the particular organ or body
parts are of research interest, as when the initial assessment is
considered.
Te selection between the simplifed single organ model
and the more detailed and complete body model is not simple
nor straightforward. Tis paper is an extension of recent study
[8] on the comparison of the results between the compound
and the extracted eye models, respectively, exposed to 1 GHz
electromagnetic plane wave at single polarization. Tis paper
Hindawi
Mathematical Problems in Engineering
Volume 2017, Article ID 7932604, 12 pages
https://doi.org/10.1155/2017/7932604