A5041954621- Electromagnetic Fields and Biological Effects
- Wireless Body Area Networks
- Ultrasound and Hyperthermia Applications
- Energy Harvesting in Wireless Networks
- Transcranial Magnetic Stimulation Studies
- Wireless Power Transfer Systems
- Infrared Thermography in Medicine
- Neuroscience and Neural Engineering
- EEG and Brain-Computer Interfaces
- Microwave Imaging and Scattering Analysis
- Muscle activation and electromyography studies
- Electromagnetic Compatibility and Measurements
- Thermoregulation and physiological responses
- Electrostatic Discharge in Electronics
- Climate Change and Health Impacts
- Advanced MRI Techniques and Applications
- Antenna Design and Analysis
- Functional Brain Connectivity Studies
- Gyrotron and Vacuum Electronics Research
- Noise Effects and Management
- COVID-19 epidemiological studies
- Direction-of-Arrival Estimation Techniques
- Electromagnetic Compatibility and Noise Suppression
- Antenna Design and Optimization
- Speech and Audio Processing
Nagoya Institute of Technology
2016-2025
Kyorin University
2023
University of Utah
2021
Universiti Malaysia Perlis
2021
Fujita Health University
2021
ORCID
2018
Tohoku University
2017
East Asia Research
2011
National Institute of Information and Communications Technology
2008-2010
Kanazawa Medical University
2009
This paper deals with the electric and magnetic field (EMF) safety aspects of a wireless power transfer (WPT) system based on resonant coupling between two coils. The primary coil is assumed to be on-body, while secondary inside human body connected battery recharge an active implantable medical device such as pacemaker. study allows us identify good preliminary solution WPT configuration, compensation capacitor topology, operational frequency. Demonstrative systems operating at different...
The newly released IEEE Std C95.1™-2019 defines exposure criteria and associated limits for the protection of persons against established adverse health effects from exposures to electric, magnetic, electromagnetic fields, in frequency range 0 Hz 300 GHz. apply permitted restricted environments general public unrestricted environments. These are not intended patients by or under direction physicians care professionals, as well informed volunteers scientific research studies, use medical...
Abstract The effects of transcranial direct current stimulation (tDCS) on motor cortical excitability are highly variable between individuals. Inter-individual differences in the electric fields generated brain by tDCS might play a role variability. Here, we explored whether these related to changes following anodal primary cortex (M1). Motor evoked potentials (MEPs) were measured 28 healthy subjects before and after 20 min sham or 1 mA right M1 double-blind crossover design. individually...
In this study, we analyzed the spread and decay durations of COVID-19 pandemic in several cities China, England, Germany, Japan, where first wave has undergone decay. Differences medical health insurance systems, as well regional policies incommoded comparison different countries. The four studied countries were reordered calculated based on an asymmetric bell-shaped model. We acquired values ambient temperature, absolute humidity, population density to perform multivariable analysis. found...
A low-power consumption, small-size smart antenna, named electronically steerable parasitic array radiator (ESPAR), has been designed. Beamforming is achieved by tuning the load reactances at elements surrounding active central element. fast beamforming algorithm based on simultaneous perturbation stochastic approximation with a maximum cross correlation coefficient criterion proposed. The simulation and experimental results validate algorithm. In an environment where...
Responses elicited by transcranial magnetic stimulation (TMS) over the hand motor area depend on position and orientation of stimulating coil. In this work, we computationally investigate induced electric field for multiple coil orientations locations in order to determine which parts brain are affected how sensitivity cortical activation depends direction field. The finite element method is used calculating TMS two individual anatomical models head brain. affects both strength depth...
In transcranial magnetic stimulation (TMS), the distribution of induced electric field, and affected brain areas, depends on position coil individual geometry head brain. The field in realistic anatomies can be modelled using computational methods. However, existing methods for accurately determining anatomical models have suffered from long computation times, typically range tens minutes or longer. This paper presents a matrix-free implementation finite-element method with geometric...
The electric field produced in the brain is main physical agent of transcranial direct current stimulation (tDCS). Inter-subject variations fields may help to explain variability effects tDCS. Here, we use multiple-subject analysis study strength and group-level standard space. Personalized anatomically-accurate models 62 subjects were constructed from T1- T2-weighted MRI. finite-element method was used computationally estimate individual fields, which registered space using surface based...
This study analyzed the morbidity and mortality rates of coronavirus disease (COVID-19) pandemic in different prefectures Japan. Under constraint that daily maximum confirmed deaths cases should exceed 4 10, respectively, 14 were included, cofactors affecting evaluated. In particular, number was assessed, excluding nosocomial infections nursing home patients. The correlations between population density statistically significant (p-value < 0.05). addition, percentage elderly also found to...
From extremely low frequencies to intermediate frequencies, the magnitude of induced electric field inside human body is used as metric for protection. The can be computed using anatomically realistic voxel models and numerical methods such finite-difference or finite-element methods. affected by errors that occur when curved boundaries with large contrasts in electrical conductivity are approximated a staircase grid. In order lessen effect approximation error, use 99th percentile field,...
BackgroundIn transcranial direct current stimulation (TDCS), electric is applied via two large electrodes to modulate brain activity. Computational models have shown that produce diffuse fields (EFs) in the brain, which depends on individual head and anatomy. Recently, smaller as well novel electrode arrangements, including high-definition TDCS (HD-TDCS) montages, been introduced improve focality of EFs. Here, we investigated whether EFs focal montages are more susceptible interindividual...
Highlights•Clinical and research NIBS operations are important in some cases critical to continue through the COVID-19 pandemic.•We provide a framework for maintaining their safety during future outbreaks.•Guidelines good practices managing reopening clinics laboratories presented.•Remotely supervised tDCS provides opportunity clinical treatments patients at home while staff offsite.•Onsite brain stimulation, such as TMS, can proceed when implementing workflows ensuring related...
Transcranial alternating current stimulation (tACS), which is a novel technique for the manipulation of cortical oscillations, can generate subjective visual sensations (phosphenes). In this work, we computationally investigate that reaches eyes from tACS electrodes in order to show phosphenes induced by are retinal origin.The finite-element method used modelling path an anatomically realistic model head various electrode montages. The computational results analysing previous experimental...
This article reviews recent standardization activities and scientific studies related to the assessment of human exposure electromagnetic fields (EMF). The differences standards consumer products medical applications are summarized. First, we reviewed body modeling tissue dielectric properties. Then, explain rationale current from viewpoint EMF process for product compliance based on these standards. wireless power transfer, as an example emerging devices, environmental EMFs in our daily...
This study analyzed the spread and decay durations of COVID-19 pandemic in different prefectures Japan. During pandemic, affordable healthcare was widely available Japan medical system did not suffer a collapse, making accurate comparisons between possible. For 16 included this that had daily maximum confirmed cases exceeding ten, number follow bell-shape or log-normal distribution most prefectures. A good correlation observed durations. However, some exceptions were areas where travelers...
Two international guidelines/standards for human protection from electromagnetic fields define the specific absorption rate (SAR) averaged over 10 g of tissue as a metric against localized radio frequency field exposure due to portable devices operating below 3–10 GHz. Temperature elevation is suggested be dominant effect at frequencies higher than 100 kHz. No previous studies have evaluated temperature in head local considering thermoregulation. This study aims discuss model vasodilation,...
International organizations have collaborated to revise standards and guidelines for human protection from exposure electromagnetic fields. In the frequency range of 6–300 GHz, permissible spatially averaged epithelial/absorbed power density, which is primarily derived thermal modeling, considered as basic restriction. However, averaging methods density inside tissues, only a few groups presented calculated results obtained using different conditions numerical methods. Because experimental...
The Saccharomyces cerevisiae mutant strains blocked in the protein secretion pathway are not able to induce sexual aggregation. We have utilized defect of aggregation concentrate secretion-deficient cells and identified a new gene which functions process intracellular transport. mutant, uso1, is temperature sensitive for growth secretion. At restrictive (37 degrees C), uso1 accumulated core-glycosylated precursor form exported invertase cells. Ultrastructural study fixed by...
The temperature rises in the human eye for plane wave exposures are investigated frequency range between 600 MHz and 6 GHz, which covers hot spot range. As a first step, specific absorption rates (SARs) calculated with use of finite-difference time-domain (FDTD) method mechanism hot-spot formation is discussed. Then by using Pennes' bioheat equation. In addition, dependence SARs on electromagnetic (EM) polarization dimension Furthermore, compared values found literature pertaining to...
The present study discusses the applicability of magneto-quasi-static approximation to calculation specific absorption rate (SAR) in a cylindrical model for wireless power transfer system. Resonant coils with different parameters were considered 10 MHz band. A two-step quasi-static method that is comprised moments and scalar-potential finite-difference methods applied, which can consider effects electric magnetic fields on induced SAR separately. From our computational results, SARs obtained...
This study discusses a computational method for calculating the specific absorption rate (SAR) due to wireless power transmission system in 10 MHz frequency band. A two-step quasi-static comprised of moments and scalar potential finite-difference are proposed. The applicability approximation localized exposure this band is discussed by comparing SAR lossy dielectric cylinder computed with full-wave electromagnetic analysis approximation. From results, input impedance resonant coils was...
Incident power density is used as the dosimetric quantity to specify restrictions on human exposure electromagnetic fields at frequencies above 3 or 10 GHz in order prevent excessive temperature elevation body surface. However, international standards and guidelines have different definitions for size of area over which should be averaged. This study reports computational evaluation relationship between incident averaged local peak a multi-layer model simulating body. Three wave sources are...