Electromagnetic fields in body by wireless inductive system

2015 ◽  
Vol 34 (2) ◽  
pp. 590-595 ◽  
Author(s):  
Ping-Ping Ding ◽  
Lionel Pichon ◽  
Laurent Bernard ◽  
Adel Razek
Keyword(s):  
Numerical Simulation ◽  
Electromagnetic Fields ◽  
Human Body ◽  
Magnetic Flux Density ◽  
Magnetic Vector Potential ◽  
Human Body Model ◽  
Exposure Limits ◽  
Field Exposure ◽  
Content Type ◽  
Charging System

Purpose – The purpose of this paper is to calculate the induced electromagnetic fields in human body exposed to the wireless inductive charging system of electric vehicles has been conducted based on the numerical simulation. Design/methodology/approach – A homogeneous human body model is built and a representative wireless inductive charging system is used for the exposure assessment. The numerical simulation relies on finite element method with formulations in terms of the magnetic vector potential. The electromagnetic fields in terms of magnetic flux density and electric field are computed in the human body and compared with the electromagnetic exposure limits. Findings – It has been found that the induced EMFs in the near-field exposure configuration greatly comply with the safety guidelines. Originality/value – This study could help the development of the wireless inductive charging system with meeting the safety standard of radiation protection.

COMPLIANCE TESTING FOR HUMAN BODY MODEL EXPOSURE TO ELECTROMAGNETIC FIELDS FROM A HIGH-POWER WIRELESS CHARGING SYSTEM FOR DRONES

2020 ◽  
Vol 189 (1) ◽  
pp. 13-27 ◽  
Author(s):  
Jangyong Ahn ◽  
Seon-Eui Hong ◽  
Haerim Kim ◽  
Yangbae Chun ◽  
Hyung-Do Choi ◽  
...  
Keyword(s):  
Electromagnetic Fields ◽  
Human Body ◽  
Internal Electric Field ◽  
Wireless Charging ◽  
Human Body Model ◽  
Case Scenario ◽  
Worst Case ◽  
Charging System ◽  
Compliance Testing ◽  
Human Body Models

Abstract Recently, a wireless charging system (WCS) for drones has been extensively studied, although standards for compliance testing of a WCS for drones have yet to be established. In this study, we propose methods for human exposure assessments of a WCS for drones by comprehensively considering the various positions of the system and the postures of human body models. The electromagnetic fields from a WCS are modeled and the internal quantities of the human body models, consisting of current density, internal electric field and specific absorption rate, are calculated. The incident fields around the WCS and the internal quantities are analyzed at 140 kHz, which is the operating frequency of the WCS applied. Results of an exposure assessment based on the confirmed worst-case scenario are presented. In addition, the internal quantities depending on the human body models and the material characteristics of the simplified models are also discussed using four different anatomical and simplified human body models.

A New Method to Concentrate Electromagnetic Field Within ROI Using a High Dielectric Material in 3T Body MRI

2013 ◽  
Author(s):  
Bu S. Park ◽  
Sunder S. Rajan ◽  
Leonardo M. Angelone
Keyword(s):  
Numerical Simulation ◽  
Electromagnetic Field ◽  
Human Body ◽  
Region Of Interest ◽  
Dielectric Materials ◽  
The Body ◽  
Human Body Model ◽  
Body Model ◽  
Simulation Results ◽  
High Dielectric

We present numerical simulation results showing that high dielectric materials (HDMs) when placed between the human body model and the body coil significantly alter the electromagnetic field inside the body. The numerical simulation results show that the electromagnetic field (E, B, and SAR) within a region of interest (ROI) is concentrated (increased). In addition, the average electromagnetic fields decreased significantly outside the region of interest. The calculation results using a human body model and HDM of Barium Strontium Titanate (BST) show that the mean local SAR was decreased by about 56% (i.e., 18.7 vs. 8.2 W/kg) within the body model.

scholarly journals Computation of currents induced by ELF electric fields in anisotropic human tissues using the Finite Integration Technique (FIT)

2005 ◽  
Vol 3 ◽  
pp. 227-231 ◽  
Author(s):  
V. C. Motrescu ◽  
U. van Rienen
Keyword(s):  
Dielectric Properties ◽  
Electromagnetic Fields ◽  
Electric Fields ◽  
Human Body ◽  
Low Frequency ◽  
Integration Technique ◽  
Human Body Model ◽  
Body Model ◽  
Finite Integration Technique ◽  
Muscle Tissues

Abstract. In the recent years, the task of estimating the currents induced within the human body by environmental electromagnetic fields has received increased attention from scientists around the world. While important progress was made in this direction, the unpredictable behaviour of living biological tissue made it difficult to quantify its reaction to electromagnetic fields and has kept the problem open. A successful alternative to the very difficult one of performing measurements is that of computing the fields within a human body model using numerical methods implemented in a software code. One of the difficulties is represented by the fact that some tissue types exhibit an anisotropic character with respect to their dielectric properties. Our work consists of computing currents induced by extremely low frequency (ELF) electric fields in anisotropic muscle tissues using in this respect, a human body model extended with muscle fibre orientations as well as an extended version of the Finite Integration Technique (FIT) able to compute fully anisotropic dielectric properties.

Magnetic particle inspection and EMF Directive 2013/35/EU

2020 ◽  
Vol 62 (2) ◽  
pp. 69-72
Author(s):  
H Bibby ◽  
J Hinsley
Keyword(s):  
Risk Assessment ◽  
Electromagnetic Fields ◽  
Magnetic Particle ◽  
Computer Modelling ◽  
Successful Outcome ◽  
Magnetic Flux Density ◽  
Field Exposure ◽  
Limit Values ◽  
Magnetic Particle Inspection ◽  
The Uk

EMF Directive 2013/35/EU [1] was transposed into legislation in EU member states in 2016. In the UK, the Health and Safety Executive (HSE) produced the Control of Electromagnetic Fields at Work (CEMFAW) Regulations 2016 [2] . It is the first piece of legislation in the UK that is specific to electromagnetic fields (EMFs) and requires all employers to perform an EMF risk assessment. For many this is a relatively easy process, as most workplaces do not contain equipment capable of producing high fields. However, any piece of equipment that uses a high level of electrical current is capable of generating a high magnetic field and, in the case of magnetic particle inspection (MPI), it is an intended output. As the operator is often required to stand close to the generated field, exposure levels can be relatively high. Magnetic flux density measurements have shown that the action levels (ALs) used as the basis for exposure assessment can be exceeded. In some instances this can be mitigated by some instruction or training, while in others it may be necessary to prove compliance with exposure limit values (ELVs). Proving compliance with ELVs is more complicated than proving compliance with ALs. It is by no means impossible, however, as computer modelling can be employed. The regulations also list categories of worker considered to be at particular risk. Pregnant workers and workers with active medical devices, such as pacemakers, or passive implants, for example artificial joints, pins, plates, screws or stents, are all considered to be at particular risk. To perform a risk assessment for such workers, reference levels contained in EU Council Recommendation 1999/519/EC [3] are used. These are much more stringent than ALs and compliance is more difficult, but a pragmatic approach can be employed to achieve a successful outcome. Fundamentally, the purpose of the regulations is not to place obstacles in the way of industry but to make employers and equipment manufacturers aware of their obligations and the possible routes that can be taken to achieve compliance.

Hierarchical paradigm for automated optimal design of dual-band wearable antenna with simplified human body models

2018 ◽  
Vol 37 (5) ◽  
pp. 1597-1608 ◽  
Author(s):  
Lukasz Januszkiewicz ◽  
Paolo Di Barba ◽  
Slawomir Hausman
Keyword(s):  
Optimal Design ◽  
Human Body ◽  
Automated Design ◽  
Dual Band ◽  
Design Parameters ◽  
Hierarchical Approach ◽  
Human Body Model ◽  
Content Type ◽  
Body Model ◽  
Wearable Antennas

Purpose The purpose of this study is to develop a method to reduce the computation time necessary for the automated optimal design of dual-band wearable antennas. In particular, the authors investigated if this can be achieved by the use of a hierarchical optimization paradigm combined with a simplified human body model. The geometry of the antenna under consideration is described via eight geometrical parameters which are automatically adjusted with the use of an evolutionary algorithm to improve the impedance matching of an antenna located in the proximity of a human body. Specifically, the antennas were designed to operate in the ISM band which covers two frequency ranges: 2.4-2.5 GHz and 5.7-5.9 GHz. Design/methodology/approach During the studies on the automated design of wearable antennas using evolutionary computing, the authors observed that not all design parameters exhibit equal influence on the objective function. Therefore, it was hypothesized that to reduce the computation effort, the design parameters can be activated sequentially based on their influence. Accordingly, the authors’ computer code has been modified to include this feature. Findings The authors’ novel hierarchical multi-parameter optimization method was able to converge to a better solution within a shorter time compared to an equivalent method not exploiting automatic activation of an increasing number of design parameters. Considering a significant computational cost involved in the calculation of the objective function, this exhibits a convincing advantage of their hierarchical approach, at least for the considered class of antennas. Research limitations/implications The described method has been developed for the design of single- or dual-band wearable antennas. Its application to other classes of antennas and antenna environments may require some adjustments of the objective functions or parameter values of the evolutionary algorithm. It follows from the well-recognized fact that all optimization methods are to some extent application-specific. Practical implications Computation load involved in the automated design and optimization can be significantly reduced compared to the non-hierarchical approach with a heterogeneous human body model. Originality/value To the best of the authors’ knowledge, the described application of hierarchical paradigm to the optimization of wearable antennas is fully original, as well as is its combination with simplified body models.

scholarly journals The Role of the Location of Personal Exposimeters on the Human Body in Their Use for Assessing Exposure to the Electromagnetic Field in the Radiofrequency Range 98–2450 MHz and Compliance Analysis: Evaluation by Virtual Measurements

2015 ◽  
Vol 2015 ◽  
pp. 1-12 ◽  
Author(s):  
Krzysztof Gryz ◽  
Patryk Zradziński ◽  
Jolanta Karpowicz
Keyword(s):  
Human Body ◽  
Measurement Errors ◽  
The Body ◽  
Back Side ◽  
Human Body Model ◽  
Field Exposure ◽  
Limit Values ◽  
Exposure Limit ◽  
Measurement Results ◽  
Exposure Conditions

The use of radiofrequency (98–2450 MHz range) personal exposimeters to measure the electric field (E-field) in far-field exposure conditions was modelled numerically using human body model Gustav and finite integration technique software. Calculations with 256 models of exposure scenarios show that the human body has a significant influence on the results of measurements using a single body-worn exposimeter in various locations near the body ((from −96 to +133)%, measurement errors with respect to the unperturbedE-field value). When an exposure assessment involves the exposure limitations provided for the strength of an unperturbedE-field. To improve the application of exposimeters in compliance tests, such discrepancies in the results of measurements by a body-worn exposimeter may be compensated by using of a correction factor applied to the measurement results or alternatively to the exposure limit values. The location of a single exposimeter on the waist to the back side of the human body or on the front of the chest reduces the range of exposure assessments uncertainty (covering various exposure conditions). However, still the uncertainty of exposure assessments using a single exposimeter remains significantly higher than the assessment of the unperturbedE-field using spot measurements.

scholarly journals Numerical modelling of the forklift tip-over to test effectiveness of the safety components

2016 ◽  
Author(s):  
Marcin Milanowicz ◽  
Paweł Budziszewski ◽  
Krzysztof Kędzior
Keyword(s):  
Numerical Simulation ◽  
Numerical Modelling ◽  
Numerical Simulations ◽  
Head And Neck ◽  
Human Body ◽  
Human Body Model ◽  
Body Model ◽  
Internal Transport

Forklift overturning with its operator is the most common and dangerous type of an accident involving internal transport. The forklifts are equipped with safety components to avoid, or reduce the effects of forklift tip-over. However, there is very few information on the effectiveness of such systems. The aim of the research was to evaluate their effectiveness with the use of numerical simulation. The study relied on carrying out numerical simulations of forklift overturning with its operator. Active human body model was used in the research. Human body output parameters, e.g. forces and accelerations of the head and neck were used to estimate injuries sustained by an operator. The effectiveness of the safety components was assessed on the basis of estimated injuries.

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