Knee osteoarthritis (OA) is one of the most common musculoskeletal diseases, and the number of patients is expected to increase in Japan. In recent years, gait analysis using inertial measurement units (IMUs) has been attracting attention. In this study, we quantified the knee flexion angle during gait in patients with knee OA using IMUs and sensor fusion considering centrifugal and tangential acceleration. And we compared the results between healthy participants and patients with knee OA to validate the usefulness of the system. As a sensor fusion, an extended kalman filter was constructed to correct the posture of IMUs using the corrected values of centrifugal and tangential acceleration using the accelerometer and gyroscope. Gait measurement experiments were conducted on healthy participants and patients with knee OA mounting IMUs. As a result, estimated knee flexion angle during gait of patients with knee OA showed patient-specific waveform flattening and amplitude changes different from those of healthy participants, indicating that is useful for clinical gait analysis.

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In this study, the purpose is to design a minimum layout about a device to obstacles in front and sides of an automated guided vehicle (AGV) at the same time using a two-dimensional laser range scanner and mirrors. The results were as follows. Mechanism of the minimum layout design was shown. On the basis of the mechanism, concrete design method was shown about reflecting points and receiving areas, an angle and the width of the mirror in side, the minimum layout area, and a scanning area in front. By use of the design method, design results were shown about a number of different-sized scanner and AGV. By use of actual scanner and mirrors, performance of the minimum layout design was evaluated to lay out actual obstacles and size of the AGV.

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Supporting the elderly by utilizing their remaining functions will lead to the extension of their healthy life span. In this study, we developed a portable cane-type standing and sitting positional mobility support device. In this study, we developed a cane-type mobility support device, and selected a suitable support direction for elderly people by dynamic analysis simulation. In addition, the necessary assisting force for the elderly was examined and the assisting force was set. The effectiveness of the device was evaluated by measuring the surface electromyogram of healthy subjects. As a result, it was found that the specifications of this device were effective when the assist direction was 30 degrees and the assist force was 110 N. From the measurement of the surface electromyogram, it was found that the device was effective for both standing and sitting motions. It also helps to ensure the safety of the sitting motion of elderly people.

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An artifact metric system (with laser microscope as a sensing device) covers flat and sheet artifacts. Previous paper has introduced an aluminum foil as the artifact, but we introduce a decorative printing as a better artifact. This is because it would enhance the accuracy of authentication and improve the difficulty of counterfeiting due to the following reasons: (1) Wide variety of metallic colors can be printed on-demand, (2) Unique printing layer is formed randomly due to the existence and irregular movement of solvent, resin, bubbles and metal powder within the ink, and (3) The roughness formed on the surface of the printing layer is finer than aluminum foil. We found that each valley depicted by decorative printing's FAR and FRR curves came from three types of images was almost the same or deeper than that of aluminum foil.

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This paper focuses on onomatopoeia conversion based on multimodal environmental sound recognition, and reports on a proto-type system that uses this method to support the hearing-impaired. We proposed and prototyped a system using multimodal en-vironmental sound recognition-based onomatopoeia conversion and speech recognition. In this prototype system, text converted by speech recognition and onomatopoeia converted by environmental sound recognition are presented on an AR headset. This system achieves multimodal recognition by integrating the results of object detection and environmental sound recognition by Convolutional Neural Network into the final recognition result. We report on experiments showing that multimodal recognition enables highly accurate environmental sound recognition.

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Recently, the introduction of wind power generation has been carried out actively. However, lightning damage to wind power systems have been increasing. We paid attention to surface discharge characteristics as a counterplan for lightning damage. In this study discharge tests using high-strength discharge inducer material was conducted to examine its effectiveness in guiding lightning strikes.

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In the automotive industry, electrical double-layer capacitors (EDLC) are being considered as the storage batteries for the next-generation automobiles. In this regard, we developed an EDLC charge and discharge control circuit built in the vehicle to control the voltage and current. We were able to produce an EDLC charge and discharge control system that can repeatedly cycle through charge and discharge in approximately 800 seconds.

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Theoretically, the charge/ discharge cycle life of Electric Double Layer Capacitor (EDLC) is infinite. We use electrolysis solution and it is difficult to directly measure the capacity or capacity reduction rate based on the life of the electrolysis solution. We conducted accelerated aging tests with repeated charge/discharge cycle for 27 days in the constant-temperature bath at 60 ℃ to measure the capacitance closely related to electrolysis solution. The result of the aging tests showed that capacitance dropped by about 12 %. With some EDLC, electrolysis solution spurted causing the breakage of EDLC.

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