Publications by authors named "S Umeno"
Fatigue assessment for back-support exoskeletons during repetitive lifting tasks.
Front Bioeng Biotechnol
September 2024
Article Synopsis
- * Exoskeletons are seen as a potential solution to reduce worker fatigue, but evaluating their safety and effectiveness can be challenging beyond using electromyography (EMG).
- * The study developed a simulation method combining exoskeleton models and human body assessments, showing results similar to EMG measurements for repetitive lifting tasks, offering valuable insights for product design.
Dynamic assessment for low back-support exoskeletons during manual handling tasks.
Front Bioeng Biotechnol
November 2023
Article Synopsis
- Exoskeletons are designed to protect the lumbar spine and lower the risk of back injuries during lifting tasks, but their effectiveness varies depending on the movements performed.
- Traditional studies often focus on peak biomechanical data, neglecting crucial time-specific performance aspects, which this research aims to address through a functional analysis using continuous data visualization.
- The findings indicate that while exoskeletons significantly reduce lumbar load during lifting, they may also limit movement, and their effectiveness is minimal at smaller trunk angles, highlighting the need for better exoskeleton design for injury prevention.
SURFACE DOSE ESTIMATION BY A KAP METER FOR KILOVOLTAGE X-RAY BEAMS.
Radiat Prot Dosimetry
September 2021
This study aims to estimate the entrance surface dose (ESD) of a water phantom for kilovoltage x-ray beams using an air kerma area product meter (KAP meter) equipped in an x-ray unit. The KAP meter was calibrated in terms of the ESD determined by a plane-parallel ionization chamber based on a 60Co absorbed dose-to-water calibration coefficient, ${N}_{D,w}^{{}^{60}\mathrm{C}\mathrm{o}}$. The ESD measured using the KAP meter was verified by comparing it with that estimated by the air kerma calibration coefficient, NK, for x-ray beam qualities.
View Article and Find Full Text PDFBackground: Frequently observed sleep/wake problems among pregnant women need comprehensive evaluation. This study was conducted to clarify the sleep/wake problems among pregnant women without gestational complications during the second and third trimester and the effects of sleep/wake problems on delivery outcomes.
Methods: A total of 88 Japanese pregnant women participated in this study.
The purpose of this study was to develop a new ionization chamber dosimetry formalism for diagnostic kilovoltage x-ray beams based on a Co absorbed dose-to-water calibration coefficient [Formula: see text]. To validate the new chamber dosimetry, 39 fluence spectra of kilovoltage x-rays were calculated, using a SpekCalc program, for Al half-value-layer (Al-HVL) values of 1.4-8.
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