Publications by authors named "Keisuke Yoshioka"

In recent years, individual control of one's personal environment has been drawing increasing attention due to the growing interest in health care. Wearable devices are especially useful because of their controllability regardless of location. Humidity is one of the inevitable factors in the personal environment as a preventive against infectious diseases.

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Vibroarthrographic (VAG) signals are sounds or vibrations caused when a knee joint is flexed or stretched. VAG signal collection is noninvasive and can be performed using an accelerometer or microphone attached to the skin. However, the sensor attached to the skin will move with the soft tissue caused by flexion and extension, causing the baseline of the VAG signal to drift.

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In the geometric design of roundabouts, safety-oriented approaches are required rather than specification design ones that simply determine the dimensions of the geometric structural elements. We herein propose a risk index (RI) that combines the invisibility probability and the crash impact as a performance measure for evaluating the safety of the geometric designs of roundabouts, and we also describe a method for calculating this index. Invisibility probability represents the probability that an entering vehicle cannot view a vehicle coming from the upstream in a circulatory roadway and crash impact represents the amount of lost kinetic energy at the time of collision corresponds to the impact of the crash.

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We developed a wideband quasi-optical band-pass filter covering 170-520 GHz by exploiting the recent advancements in commercially available flexible printed circuit (FPC) fabrication technologies. We designed and fabricated a three-layered stack of loaded hexagonal grid metal meshes using a copper pattern with a narrowest linewidth of 50µ on a polyimide substrate. The measured frequency passband shape was successfully reproduced through a numerical simulation using a set of parameters consistent with the dimensions of the fabricated metal meshes.

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We used non-invasive broadband ultrasound attenuation (BUA) to determine whether the pre-surgical bone quality of the calcaneus was improved 5years postoperatively, and whether the interval between total knee arthroplasty (TKA) surgeries influenced post-surgical calcaneal bone quality. All patients underwent scheduled, staged, bilateral TKA. Twenty-one patients (42 TKAs) with bilateral knee osteoarthritis were evaluated.

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