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Electromagnetic Fields in Biological Systems
Dimbylow (1998, 2000) has developed a male phantom model called NORMAN at
NRPB. Its name is derived from NORmalised MAN. The resolution of that model is
2.077 × 2.077 × 2.021 mm 3 , which is cubical in shape. This model was based on MRI scans
of an adult male subject and was segmented into 37 different types. This phantom was
standardized at a height of 1.76 m and weight of 73 kg. NORMAN consisted of a threedimensional, parallel pipe–shaped array of 36 million homogeneous voxels. There were
8.3 million voxels in the body, and the remaining voxels were located in the surrounding.
Besides the male phantom model, a female phantom model was also developed. Dimbylow
(2005, 2006) developed a female phantom model called NAOMI (aNAtOMIcal model)
based on a 23-year-old female subject who was 1.65 m tall and weighed 58 kg. The resolution was 2 × 2 × 2 mm 3 voxels and the model was segmented into 41 tissue types. A threedimensional human model based on the photographic data from the Visible Human
Project was created by the National Library of Medicine (Ackerman 1998; The Visible
Human Project 2009). The original data of the Visible Human Project were obtained
from a 38-year-old male cadaver (1.86-m height and 90-kg weight).
Nagaoka et al. (2002, 2004) developed realistic, high-resolution, whole-body voxel
models of a standing Japanese adult male and female, which were conducive to the dosimetry of radiofrequency EMF. Based on MRI data, these models consisted of cubic voxels
of 2 mm on each side and were segmented into 51 anatomic regions. The male was named
TARO (22-year-old, 1.73 m in height, and a weight of 65.0 kg) and the female was named
HANAKO (22-year-old, 1.6 m in height, and a weight of 53.0 kg). The MRI 256 × 256 axial
Pixels were set with a 240-mm field of view (FOV) for the head and 480-mm FOV for other
parts of the body. In addition, they developed postured human models based on anatomically realistic voxel models with a standing posture (Nagaoka and Watanabe 2008).
Although these models were originally developed for electromagnetic dosimetry in the RF
region, the calculation of induced current densities in the ELF region is presented using
this whole-body numeric model and a quasistatic FDTD method (Hirata and Fujiwara
2007). This whole-body model is freely available to the scientific community through
NICT. As the Virtual Family, the anatomically correct whole-body human models of an
adult male, an adult female, and two children were developed for numerical evaluation of
electromagnetic exposure (Christ et al. 2010). These Virtual Family models are based on
high-resolution MRIs of healthy volunteers and CAD-based three-dimensional models.
The family is comprised of an adult man, Duke (34 year old, 1.74 m in height), an adult
woman, Ella (26 year old, 1.6 m in height), an 11-year-old girl Billie (1.48 m in height), and
a 6-year-old boy Thelonious (1.07 m in height). The segmentation consists of more than 80
different tissues and organs. The voxel size is in the range of 1 to 5 mm 3 . All four models
from the Virtual Family are also freely available to the scientific community through IT’IS
and are being widely applied in several studies on EMF exposure (IT’IS 2010). In addition
to the basic models of the Virtual Family, four models were built as the Virtual Classroom.
The refinement of human models over time is a function of the evolution of computer
technology, including computer memory, computational time, and computer graphic
techniques. Subsequently, numerical methods have been developed to devise human
body models based on millimeter-resolution anatomy, using MRI scan data, allowing
for the determination of the induced electric fields and current densities attributed to
the exposure to ELF EMF.