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...

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...

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...

A novel symmetrical coupled-line circuit structure without patterned ground plane is proposed to design tight-coupling high-directivity couplers, which would be found in numerous applications a microstrip RF front end because of its simple and inherent excellent compatibility. Based on traditional even- odd-mode technique, closed-form mathematical equations for both electrical parameters scattering are obtained. Due the use two sections placed vertical direction, directivity this coupler any...

The averaged absorbed power density (APD) and temperature rise in body models with nonplanar surfaces were computed for electromagnetic exposure above 6 GHz. Different calculation schemes the APD investigated. Additionally, a novel compensation method correcting heat convection rate on air/skin interface voxel human was proposed validated. can be easily incorporated into bioheat calculations does not require information regarding normal direction of boundary voxels, contrast to previously...

International guidelines and standards for human protection from electromagnetic fields have been revised recently. The Epithelial/absorbed power density (APD) has used as a new physical quantity local exposure to frequencies >6 GHz, related the temperature rise in superficial layer. assessment methods of APD practical scenarios are crucial realistic exposures. This study investigates averaging nonplanar skin models field 10 90 GHz. Eight research groups compared calculated APDs using...

Abstract Objective: Computational uncertainty and variability of power absorption temperature rise in humans for radiofrequency (RF) exposure is a critical factor ensuring human protection. This aspect has been emphasized as priority. However, accurately modeling head tissue composition assigning dielectric thermal properties remains challenging task. study investigated the impact segmentation-based versus segmentation-free models assessing localized RF exposure. 
Approach: Two...

Recently, international exposure guidelines/standards for human protection from electromagnetic fields were revised. For frequencies between 6-300 GHz, the permissible incident power density is defined as reference level, which derived a new metric “absorbed/epithelial density” based on thermal modeling. However, only few groups computed and resultant temperature rise at greater than 6 where their conditions different. This study presents first intercomparison of in body exposed to different...

Anatomical human models have been widely used in the assessment of induced field strength for low-frequency (LF) electromagnetic exposure. One bottleneck is assignment a single electrical conductivity to all voxels corresponding tissue. This simplification known cause computational artifact; therefore, large reduction factor was considered international guidelines and standards. Recently, head with nonuniform conductivities generated using deep learning networks were proposed, effect on...

In order to perfectly match arbitrary frequency-dependent complex load impedances at two uncorrelated frequencies, a novel coupled-line impedance transformer without transmission-line stubs is proposed in this paper.This mainly features small size, wide bandwidth, simple analytical design method, and easy planar implementation.The simply consists of coupledline section an additional section.Due the usage section, theoretical synthesis becomes very when compared with previous transformers...

IEEE C95.1 (radio frequency) and C95.6 (low standards for human protection from electromagnetic fields are currently under revision. In the next revision, they will be combined into one standard covering frequency range 0 Hz to 300 GHz. Although considers anatomical models deriving relationship between internal external field strengths, homogeneous ellipses used in standard. guidelines of International Commission on Non-Ionizing Radiation Protection, together with reduction factors account...

ICNIRP and IEEE publish standards/guidelines for exposures to low-frequency electromagnetic fields their associated in situ electric fields. Two methods are prescribed spatially averaging the field evaluate compliance: (1) over a 2 mm × volume (ICNIRP) (2) along 5 linear segment of neural tissue (IEEE). However, detailed calculation procedures these two schemes not provided, particularly when volume/line straddles tissue/air or tissue/tissue interface. This study proposes implementing...

This article reports on an intercomparison study the effect of incidence angle spatial average incident power density (PD) and resultant temperature rise using computational thermographic measurement approaches. Two definitions PD—the peak spatial-average normal component Poynting vector norm vector—were compared. First, PD in a layered skin model was conducted for 4 × dipole array antenna. The variations caused by antenna type, antenna-body distance, to these were then discussed. results...

To protect humans from overexposure to electromagnetic (EM) fields above 6 GHz, recently revised International Commission on Non-Ionizing Radiation Protection guidelines and IEEE standard specify the basic restrictions in terms of absorbed power density (APD) epithelial density, respectively. assess EM exposure resulting 5G mmWave array antenna, we adopted a hybrid method that combines spherical near-field measurements numerical dosimetry with transformation. Four antennas working at 28 GHz...

In international guidelines and standards for human protection from electromagnetic fields, mass-averaged specific absorption rate (SAR) is used as a metric to prevent excessive temperature rise at frequencies up 6 GHz. Above this transition frequency, including the frequency region assigned fifth-generation (5G) wireless communication systems, area-averaged absorbed power density (APD) or epithelial physical quantity specify restrictions on exposure. 5G above below GHz may be...

The International Commission on Non-Ionizing Radiation Protection (ICNIRP) guidelines and the IEEE C95.1 standard are currently under revision. In guidelines/standard, dominant effect for electromagnetic field exposures at frequencies above 100 kHz is thermal effect. whole-body-and 10g-averaged specific absorption rates (SARs), which surrogates core local temperature elevations, respectively, set as metrics exposure evaluation. external strengths or incident power density, corresponding to...

In this article, we propose a novel metasurface-basedmagnetic coupling resonant wireless power transfer (MCR-WPT) system to realize planar omnidirectional WPT at mid-range distance. The resonator devices—dielectric-constant disks or helixes—are located on both sides of the metasurface, which comprises conducting wires placed in sunburst pattern. Transmission efficiency >40% is achieved circular plane with diameter ∼40 cm. addition, insensitive placement human hand near proposed MCR-WPT...

Radiation from mobile phones inside vehicles, which are semiopen metallic enclosures with irregular shapes and apertures, has been a major concern warranted investigation in past years. In this paper, the specific absorption rate (SAR) induced phone users vehicle was evaluated using different scenarios, including handedness, passenger counts, seating locations. A computer simulation for SAR distributions human body performed based on finite-difference time-domain method. The values free...

This article investigates variations in specific absorption rate and temperature rise human eye caused by changes palpebral fissure, the extent of opening between eyelids, under GHz plane‐wave electromagnetic (EM) exposures. Detailed head models with different fissure features were developed a refined spatial resolution 0.25 mm. These then incorporated into both EM bio‐heat simulations, but using finite‐difference time‐domain method method, respectively. Maximum lens was found to be 0.8°C...

Objective.In the low-frequency exposure (<100 kHz), induced electric field strength is used as a metric for assessment human protection. Unlike radio-frequency (>MHz), computational suffers from staircasing error in biological objects. The international guidelines consider additional reduction factor of 3 when setting limit. Here we propose new method to reduce skin magnetic dosimetry voxelized body models.Approach. We have proposed considering filling ratio tissue air-skin and skin-fat...

Accurate delineation of Gross Tumor Volume (GTV) is crucial for radiotherapy. Deep learning-driven GTV segmentation technologies excel in rapidly and accurately delineating GTV, providing a basis radiologists formulating radiation plans. The existing 2D 3D models based on deep learning are limited by the loss spatial features anisotropy respectively, both affected variability tumor characteristics, blurred boundaries, background interference. All these factors seriously affect performance....