Search research articles

ABOUT JoVE

Overview Leadership Blog JoVE Help Center

AUTHORS

Publishing Process Editorial Board Scope & Policies Peer Review FAQ Submit

LIBRARIANS

Testimonials Subscriptions Access Resources Library Advisory Board FAQ

RESEARCH

JoVE Journal Methods Collections JoVE Encyclopedia of Experiments Archive

EDUCATION

JoVE Core JoVE Business JoVE Science Education JoVE Lab Manual Faculty Resource Center Faculty Site

Terms & Conditions of Use

Related Concept Videos

Power Factor Correction

Power Factor Correction

The power transmission to a factory involves the transfer of apparent power, a combination of active and reactive power. The power factor measures how effectively electrical power is converted into useful work output. The ratio of the real power (KW) that does the work to the apparent power (KVA) supplied to the circuit.

Calculation of Self-inductance

Calculation of Self-inductance

The self-inductance of a circuit, often simply called the inductance, is a purely geometric factor that depends only on the circuit component's structure. More specifically, it depends on the shape and size of the component that lets the flux pass through it, thus inducing an electric field that opposes any current passing through it.
Since the effect of the induced electric field and the back EMF generated depends on the rate of change of current and the self-inductance, the inductance...

Mesh Analysis for AC Circuits

Mesh Analysis for AC Circuits

In the domain of radio communication, the significance of impedance matching must be considered. It is crucial to ensure the efficient transmission of signals between radio transmitters and receivers. Achieving this balance involves using impedance-matching circuits, with one fundamental configuration comprising a resistor, capacitor, and inductor.
The process of harmonizing these impedances begins with a clear understanding of the input and output signals. Once these signals are known, the...

The Maximum Power Transfer Theorem

The Maximum Power Transfer Theorem

Consider a linear AC Thevenin equivalent circuit connected to a load impedance.
The load connected draws the current, and the circuit delivers the power to the load. The alternating current flowing through the load is determined using the rectangular form of voltages, currents, network impedance, and load impedance. The average power delivered to the load is obtained from the product of the square of current and load resistance.

Fast Decoupled and DC Powerflow

Fast Decoupled and DC Powerflow

The fast decoupled power flow method addresses contingencies in power system operations, such as generator outages or transmission line failures. This method provides quick power flow solutions, essential for real-time system adjustments. Fast decoupled power flow algorithms simplify the Jacobian matrix by neglecting certain elements, leading to two sets of decoupled equations:

Calculation of Electric Flux

Calculation of Electric Flux

Consider the electric field of an oppositely charged, parallel-plate system and an imaginary box between those plates. Let the bottom face of the box be ABCD, and the top face be FGHK. The electric field between the plates is uniform and points from the positive plate toward the negative plate. The calculation of this field's flux through the box's various faces shows that the net flux through the box is zero. Why does the flux cancel out here?

You might also read

Related Articles

Articles linked to this work by shared authors, journal, and citation graph.

Sort by

Same author

5G RF-EMFs Mitigate UV-Induced Genotoxic Stress Through Redox Balance and p38 Pathway Regulation in Skin Cells.

Antioxidants (Basel, Switzerland)·2026

Same author

Exposure to Radiofrequency Electromagnetic Fields Enhances Melanin Synthesis by Activating the P53 Signaling Pathway in Mel-Ab Melanocytes.

International journal of molecular sciences·2024

Same author

Effects of 4G Long-Term Evolution Electromagnetic Fields on Thyroid Hormone Dysfunction and Behavioral Changes in Adolescent Male Mice.

International journal of molecular sciences·2024

Same author

Proposed Safety Guidelines for Patient Assistants in an Open MRI Environment.

International journal of environmental research and public health·2022

Same author

An Out-of-Phase Wireless Power Transfer System for Implantable Medical Devices to Reduce Human Exposure to Electromagnetic Field and Increase Power Transfer Efficiency.

IEEE transactions on biomedical circuits and systems·2022

Same author

A Novel Interposer Channel Structure with Vertical Tabbed Vias to Reduce Far-End Crosstalk for Next-Generation High-Bandwidth Memory.

Micromachines·2022

Search research articles

Related Experiment Video

Updated: Oct 7, 2025

Effective Analysis of Human Exposure Conditions with Body-worn Dosimeters in the 2.4 GHz Band

Effective Analysis of Human Exposure Conditions with Body-worn Dosimeters in the 2.4 GHz Band

Published on: May 2, 2018

Improved Calculation Method of Coupling Factors for Low-Frequency Wireless Power Transfer Systems.

Jangyong Ahn¹, Seon-Eui Hong², Haerim Kim¹

¹The CCS Graduate School of Green Transportation, Korea Advanced Institute of Science and Technology (KAIST), Daejeon 34051, Korea.

International Journal of Environmental Research and Public Health

|January 11, 2022

Summary

This study introduces an improved method for calculating coupling factors in electromagnetic field (EMF) safety assessments. By using the 99.99th percentile, it reduces computational errors in human body models, ensuring more accurate EMF exposure evaluations.

Keywords:

coupling factor electromagnetic field exposure assessment wireless power transfer

More Related Videos

Design and Characterization Methodology for Efficient Wide Range Tunable MEMS Filters

Design and Characterization Methodology for Efficient Wide Range Tunable MEMS Filters

Published on: February 4, 2018

Application of a Coupling Agent to Improve the Dielectric Properties of Polymer-Based Nanocomposites

Application of a Coupling Agent to Improve the Dielectric Properties of Polymer-Based Nanocomposites

Published on: September 19, 2020

Related Experiment Videos

Last Updated: Oct 7, 2025

Effective Analysis of Human Exposure Conditions with Body-worn Dosimeters in the 2.4 GHz Band

Effective Analysis of Human Exposure Conditions with Body-worn Dosimeters in the 2.4 GHz Band

Published on: May 2, 2018

Design and Characterization Methodology for Efficient Wide Range Tunable MEMS Filters

Design and Characterization Methodology for Efficient Wide Range Tunable MEMS Filters

Published on: February 4, 2018

Application of a Coupling Agent to Improve the Dielectric Properties of Polymer-Based Nanocomposites

Application of a Coupling Agent to Improve the Dielectric Properties of Polymer-Based Nanocomposites

Published on: September 19, 2020

Area of Science:

Electromagnetics
Computational Physics
Human Body Modeling

Background:

International Electrotechnical Commission (IEC) standards 62311 and 62233 define coupling factors for electromagnetic field (EMF) product safety assessments.
Numerical calculations are required to determine internal human body quantities for coupling factor computation.
At frequencies below 10 MHz, numerical methods can introduce segmentation or discretization errors, leading to computational artifacts in internal electric field and current density calculations.

Purpose of the Study:

To propose and validate an improved method for calculating coupling factors that mitigates computational artifacts.
To ensure accurate localized exposure assessments for electromagnetic field sources near the human body.
To enhance the reliability of compliance testing for wireless power transfer (WPT) systems.

Main Methods:

Developed a novel calculation approach applying the 99.99th percentile to determine coupling factors.
Removed computational artifacts by avoiding the use of maximum values, which may contain abnormal peaks.
Validated the proposed method using diverse human body models and wireless power transfer (WPT) systems.

Main Results:

The proposed 99.99th percentile method effectively reduces computational errors in coupling factor calculations.
Computational errors were decreased by up to 65.3% compared to conventional methods.
The improved method yields uniform coupling factors, ensuring accurate compliance with reference levels and basic restrictions.

Conclusions:

The 99.99th percentile approach provides a more robust and accurate method for calculating coupling factors in EMF safety assessments.
This technique enhances the reliability of product safety evaluations, particularly for low-frequency EMF sources.
The findings contribute to more precise compliance testing for devices like wireless power transfer systems.