scholarly journals An Efficient Deterministic-Stochastic Model of the Human Body Exposed to ELF Electric Field

2016 ◽  
Vol 2016 ◽  
pp. 1-8 ◽  
Author(s):  
Anna Šušnjara ◽  
Dragan Poljak

The paper deals with the deterministic-stochastic model of the human body represented as cylindrical antenna illuminated by a low frequency electric field. Both analytical and numerical (Galerkin-Bubnov scheme of Boundary Element Method) deterministic solutions of the problem are outlined. This contribution introduces the new perspective of the problem: the variability inherent to input parameters, such as the height of the body, the shape of the body, and the conductivity of body tissue, is propagated to the output of interest (induced axial current). The stochastic approach is based on the stochastic collocation (SC) method. Computational examples show the mean trend of both analytically and numerically computed axial current with the confidence margins for different set of input random variables. The results point out the possibility of improving the efficiency in calculation of basic restriction parameter values in electromagnetic dosimetry.

2017 ◽  
Vol 2017 (2) ◽  
Author(s):  
Kwan Tze-wan

AbstractIn the Shuowen, one of the earliest comprehensive character dictionaries of ancient China, when discussing where the Chinese characters derive their structural components, Xu Shen proposed the dual constitutive principle of “adopting proximally from the human body, and distally from things around.” This dual emphasis of “body” and “things around” corresponds largely to the phenomenological issues of body or corporeality on the one hand, and lifeworld on the other. If we borrow Heidegger’s definition of Dasein as Being-in-the world, we can easily arrive at a reformulation of Xu Shen’s constitutive principle of the Chinese script as one that concerns “bodily Dasein.” By looking into various examples of script tokens we can further elaborate on how the Chinese make use not only of the body in general but various body parts, and how they differentiate their life world into material nature, living things, and a multifaceted world of equipment in forming a core basis of Chinese characters/components, upon which further symbolic manipulation such as “indication”, “phonetic borrowing”, semantic combination, and “annotative derivation”, etc. can be based. Finally, examples will be cited to show how in the Chinese scripts the human body (and its parts) might interact with other’s bodies (and their parts) or with “things around” (whether nature, living creatures, or artifacts) in various ways to cover the social, environmental, ritual, technical, economical, and even intellectual aspects of human experience. Bodily Dasein, so to speak, provides us with a new perspective of understanding and appreciating the entire scope of the Chinese script.


Geophysics ◽  
2001 ◽  
Vol 66 (1) ◽  
pp. 137-147 ◽  
Author(s):  
Erika Gasperikova ◽  
H. Frank Morrison

The observed electromagnetic response of a finite body is caused by induction and polarization currents in the body and by the distortion of the induction currents in the surrounding medium. At a sufficiently low frequency, there is negligible induction and the measured response is that of the body distorting the background currents just as it would distort a direct current (dc). Because this dc response is not inherently frequency dependent, any observed change in response of the body for frequencies low enough to be in this dc limit must result from frequency‐dependent conductivity. Profiles of low‐frequency natural electric (telluric) fields have spatial anomalies over finite bodies of fixed conductivity that are independent of frequency and have no associated phase anomaly. If the body is polarizable, the electric field profile over the body becomes frequency dependent and phase shifted with respect to a reference field. The technique was tested on data acquired in a standard continuous profiling magnetotelluric (MT) survey over a strong induced polarization (IP) anomaly previously mapped with a conventional pole‐dipole IP survey. The extracted IP response appears in both the apparent resistivity and the normalized electric field profiles.


2010 ◽  
Vol 6 (1) ◽  
pp. 31 ◽  
Author(s):  
Cristina Peratta ◽  
Andres Peratta ◽  
Dragan Poljak

The paper introduces a three dimensional multidomainboundary element model of a pregnant woman and foetus for the analysis of exposure to high voltage extremely low frequency electric fields. The definition of the differentphysical and geometrical properties of the relevant tissues is established according to medical information available in existing literature. The model takes into account changes in geometry, body mass, body fat, and overall chemical composition in the body which influence the electrical properties, throughout the different gestational periods. The developed model is used to solve the case of exposure to overhead power transmission lines at different stages of pregnancy including weeks 8, 13, 26 and 38. The results obtained are in line with those published in the earlier works considering different approaches. In addition, a sensitivity analysis involving varying scenarios of conductivity, foetus postures and geometry for each stage is defined and solved. Finally, a correlation between the externally applied electric field and the current density inside the foetus is established and the zones of maximum exposure are identified.


2019 ◽  
Vol 72 (5) ◽  
pp. 773-778
Author(s):  
Iryna V. Markovskaya

Introduction: Low intensity electromagnetic effects possess a high biological activity, reduce the adaptive reserves of the body, impair immunity, adversely affect the functional state of the organs and body systems. The aim of the study was to identify in the experiment the effect of low-frequency electromagnetic radiation on the morphological state of the dental and periodontal tissue. Materials and methods: The experiment was conducted on WAG rats weighing 180–200 g, during which two groups were formed: group 1 (control group) included 12 WAG rats, which were not performed any manipulations; the rats of group 2 (investigation group) (n=12) for 30 days were exposed to a 70 kHz low-frequency alternating electric field (5th frequency range) daily from 9.00 to 12.00. To simulate a low-frequency 70 kHz alternating electric field, certified experimental equipment was used. The study material was the upper jaw tissue. Histological and histochemical staining methods were used. Morphometric study was conducted. Results: Complex morphological study on the experimental material allowed identifying the damaging effect of low-frequency electromagnetic radiation on the structural components of tooth and periodontal tissues. Conclusions: Our findings suggest that the workers who are exposed to occupational low-frequency electromagnetic radiation should be included in the risk group for developing diseases of the dentomandibular system in order to carry out timely therapeutic and preventive measures.


2019 ◽  
Vol 2019 ◽  
pp. 1-7
Author(s):  
Anna Šušnjara ◽  
Dragan Poljak

The paper deals with the uncertainty quantification of the transient axial current induced along the human body exposed to electromagnetic pulse radiation. The body is modeled as a straight wire antenna whose length and radius exhibit random nature. The uncertainty is propagated to the output transient current by means of the stochastic collocation method. The stochastic approach is entirely nonintrusive and serves as a wrapper around the deterministic code. The numerical deterministic model is based on the time domain Hallen integral equation solved by means of the Galerkin-Bubnov indirect boundary element method (GB-IBEM). The stochastic moments, i.e., the mean and the variance of the transient current, are calculated. Confidence margins are obtained for the whole duration of the transient response as well as for the maximal current value. The presented approach enables the estimation of the probability for the induced current to exceed the basic restrictions prescribed by regulatory bodies. The sensitivity analysis of the input parameters indicates to which extent the variation of the input parameter set influences the output values which is particularly interesting for the design of the human equivalent antenna.


2014 ◽  
Vol 1070-1072 ◽  
pp. 1159-1162
Author(s):  
Zhen Guang Liang ◽  
Can Li ◽  
Yu Ze Jiang

In the paper, electric field under overhead lines with human body existing is studied. The mixed method coupling finite element method with charge simulation method is constructed. Linkage of the finite element method domain and the charge simulation method domain is done by use of surface charge at interface. A simplified model with basic figure of human body is used. Calculation results show that human body has distortion effect on electric field nearby. Electric field at region very close to human body is greatly enhanced, while there’s little influence at region far away from the body. Head and upper side of human body play main roles of induction.


2020 ◽  
Vol E103.C (11) ◽  
pp. 588-596
Author(s):  
Masamune NOMURA ◽  
Yuki NAKAMURA ◽  
Hiroo TARAO ◽  
Amane TAKEI

2020 ◽  
Vol E103.C (8) ◽  
pp. 345-352
Author(s):  
Zhongyuan ZHOU ◽  
Mingjie SHENG ◽  
Peng LI ◽  
Peng HU ◽  
Qi ZHOU

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