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Electromagnetic Fields in Biological Systems
They also developed a detailed model in order to characterize the induced current densities in a homogeneous circular cylinder. They compared the short-circuit currents and
induced current density distributions. Based on experiments, Kaune and coworkers examined the electrical interaction between an animal and vertical uniform 60 Hz electric fields
(Kaune and Philips 1980; Kaune and Gillis 1981; Kaune 1981a,b; Kaune and Miller 1984).
They determined the electric field strengths at the surface of the body and induced current
densities inside the body. They concluded that the electric fields on the surface, as well as
the electric fields and current densities inside the body, are all strongly dependent on body
shape and its orientation to the electric fields and ground plane. They emphasized that
body shape has a major influence on the field experienced by humans or animals exposed
to uniform 60 Hz electric fields. Kaune and Phillips (1980) demonstrated the enhancement
of the surface electric fields in three species in a vertical uniform 10 kV/m electric field. The
field at the top of a human, miniature swine, and rat would be about 180, 67, and 37 kV/m,
respectively, due to the enhancement effect. The authors summarized the result of electrostatically induced electric fields in miniature swine, rat, and human models exposed
to vertical 60 Hz electric fields. The parameters in that context were total currents (shortcircuit currents), the surface electric fields, and induced currents.
Guy et al. (1982) applied the thermographic method to determine the SAR in animal
and human model tissues to help quantify the current distributions in homogeneous
bodies of arbitrary shape exposed to 60 Hz electric fields. They measured SAR for energy
deposited in models, applying 57 MHz electric fields generated from resonant cavity.
Hart et al. (1989) used a spreadsheet program to calculate the electric fields and current densities produced inside irregular shaped models representing the upper arm and
forearm. They calculated the current density distributions produced in human and rat
models concerning ELF electric fields (Hart 1990, 1992a).
Amoruso and Lattarulo (1989, 1996) applied the diakoptic theory to calculate the
induced electric fields in the human body when coupled to high ELF electric field.
The diakoptic theory was first formulated for multielement antenna analysis. In their
approach, the human body was simulated using a spatial arrangement of 11 interconnected conducting spheroids. The model calculations were based on a 1.70-m-tall
standard subject placed in a uniform 10 kV/m vertical electric field. The total current
on the grounded person, that is, the short-circuit current, is expressed as the summation
of the partial current flows capacitated through 11 elements representing the human
body. They compared the current distributions on the grounded human model with
those attributed to an ungrounded model. Based on the fundamental approach to the
theoretical modeling, they applied diakoptic theory to the dosimetric scaling problem
between mice and humans in the context of ELF electric fields. The scaling is discussed
in quasi-electrostatic conditions. The 11 elements are replaced with equal amounts of
prolate or oblate conducting spheroids.
As part of a basic approach to assess electric field effects near transmission lines, Min
et al. (1996) calculated the induced voltage and current in a modeled human and a car
close to 60 Hz, 765-kV double-circuit transmission line. They concluded that the superposition of phase arrangement was advantageous for reducing the induced voltage in
the human. However, considering the corona interference of the transmission line, this
superposition of phase arrangement had side effects such as the increase in the electric