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Image-based fall detection and classification of a user with a walking support system

Frontiers of Mechanical Engineering 2018年第3期13卷 427-441页

作者： Sajjad TAGHVAEI kazuhiro KOSUGE School of Mechanical Engineering Shiraz University Shiraz 71936- 16548 Iran Department of Bioengineering and Robotics Tohoku University Sendai 980-8579 Japan

The classification of visual human action is important in the development of systems that interact with humans. This study investigates an image-based classifica- tion of the human state while using a walking support system to improve the safety and dependability of these systems. We categorize the possible human behavior while utilizing a walker robot into eight states （i.e., sitting, standing, walking, and five falling types）, and propose two different methods, namely, normal distribution and hidden Markov models （HMMs）, to detect and recognize these states. The visual feature for the state classification is the centroid position of the upper body, which is extracted from the user＇s depth images. The first method shows that the centroid position follows a normal distribution while walking, which can be adopted to detect any non-walking state. The second method implements HMMs to detect and recognize these states. We then measure and compare the performance of both methods. The classification results are employed to control the motion of a passive-type walker （called ＂RT Walker＂） by activating its brakes in nonwalking states. Thus, the system can be used for sit/stand support and fall prevention. The experiments are performed with four subjects, including an experienced physiotherapist. Results show that the algorithm can be adapted to the new user＇s motion pattern within 40 s, with a fall detection rate of 96.25% and state classification rate of 81.0%. The proposed method can be implemented to other abnormality detection/classification applications that employ depth image-sensing devices.

关键词： fall detection walking support hidden Markov model multivariate analysis

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Nonalcoholic steatohepatitis-associated hepatocellular carcinoma:Our case series and literature review

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World Journal of Gastroenterology 2010年第12期16卷 1436-1441页

作者： Yoshitaka Takuma kazuhiro Nouso Department of Gastroenterology Kurashiki Central Hospital Department of Internal Medicine National Hospital Organization Iwakuni Clinical Center Department of Molecular Hepatology Okayama University Graduate School of MedicineDentistryand Pharmaceutical Sciences

Recently,nonalcoholic steatohepatitis(NASH) has been considered to be another cause of liver cirrhosis and hepatocellular carcinoma(HCC).The natural history and prognosis of NASH are ***,we assessed the clinicopathological features of NASH-associated HCC in our experience and reviewed the literature of NASH-associated *** experienced 11 patients with NASH-associated HCC(6 male,5 female;mean age 73.8 ± 4.9 years) who received curative ***(91%) patients had been diagnosed with obesity,diabetes,hypertension,or *** patients(64%) also had a non-cirrhotic *** recurrence-free survival rates at 1,3 and 5 years were 72%,60%,and 60%.We also summarized and reviewed 94 cases of NASH-associated HCC which were reported in the literature(64 male;mean age 66 years).The majority of patients(68%) were obese,66% of patients had diabetes,and 24% had ***,26% of the HCCs arose from the non-cirrhotic *** conclusion,patients with non-cirrhotic NASH may be a high-risk group for HCC,and regular surveillance for HCC is necessary in non-cirrhotic NASH patients as well as cirrhotic patients.

关键词： Nonalcoholic steatohepatitis Hepatocellular carcinoma Nonalcoholic fatty liver disease Cryptogenic cirrhosis

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Ultrasmall and ultradense InGaN-based RGB monochromatic micro-light-emitting diode arrays by pixilation of conductive p-GaN

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Photonics Research 2021年第12期9卷 2429-2434页

作者： ZHE ZHUANG DAISUKE IIDA kazuhiro OHKAWA Computer Electrical and Mathematical Sciences and Engineering(CEMSE)DivisionKing Abdullah University of Science and Technology(KAUST)Thuwal 23955-6900Saudi Arabia

We describe 5μm squircle InGaN-based red,green,and blue(RGB)monochromatic micro-light-emitting diodes(μLEDs)with an interpitch of 4μm by pixilation of conductive p-GaN using a H2-plasma *** p-GaN was passivated by H2 plasma and prevented the current’s injection into the InGaN quantum wells *** observed that InGaN-based redμLEDs exhibited a broader full width at half-maximum and larger peak wavelength blueshift at 11.5-115 A/cm^(2) than the green/blueμ*** on-wafer light output power density of the redμLEDs at a wavelength of 632 nm at 115 A/cm^(2) was approximately 936 mW/cm^(2),the highest value reported thus far for InGaN-based redμ*** value was comparable with that of the green/blueμLEDs at 11.5 A/cm^(2),indicating that the redμLEDs can satisfy the requirement of high brightness levels for specific *** color gamut based on InGaN RGBμLEDs covered 83.7%to 75.9%of the Rec.2020 color space in the CIE 1931 diagram at 11.5 to 115 A/cm^(2).

关键词： diode conductive light

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Metal-free catalytic reduction of aldehydes,ketones,aldimines,and ketimines

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Chinese Chemical Letters 2010年第11期21卷 1314-1317页

作者： Hiroaki Matsuoka kazuhiro Kondo Graduate School of Medical Sciences Nagoya City University Graduate School of Pharmaceutical Sciences Nagoya City University

The metal-free combination of catalytic amounts of PPh3,B（C6F5）3,and PhSiH_3 can efficiently hydrosilylate aldehydes, ketones,aldimines and ketimines to afford the corresponding reduction products in good yields.

关键词： Metal-free hydrosilylation Reduction Ketone Ketimine

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Myocarditis after COVID-19 Vaccination

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Open Journal of Emergency Medicine 2023年第1期11卷 32-36页

作者： Naoki Hashimoto kazuhiro Kashio Department of ER Sanda City Hospital Hyogo Japan Department of Cardiology Sanda City Hospital Hyogo Japan

Aim: The ongoing COVID-19 pandemic is an acute medical, social, political and economic problem. Acute myocarditis is a rare complication of the widely used mRNA-based vaccines. Case Presentation: 20-year old male with no preexisting disease or cardiovascular risk factor presented in October 2021 with chest pain after receiving the second dose of the Moderna COVID-19 vaccine 2 days previously. He discharged from ward care only a few days after his initial presentation. Conclusion: Despite the meta-analysis results suggesting a higher risk of myocarditis with COVID-19 vaccination, vaccination should still be recommended because benefits of the vaccine likely outweigh its harms.

关键词： COVID-19 mRNA-Based Vaccine Myocarditis Spike Protein

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Enzymatic synthesis of bioactive compounds by Rhus laccase from Chinese Rhus vernicifera

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Science China Chemistry 2007年第2期50卷 179-182页

作者： AKIYAMA kazuhiro MIYAKOSHI Tetsuo Department of Industrial Chemistry School of Science and TechnologyMeiji UniversityHigashi-mitaTama-kuKawasaki 214Japan

A simple one step synthesis of pinoresinol and its derivatives-active components of Du-Zhong(Eu-commia ulmoides) -from coniferyl alcohol and p-courmaryl alcohol with higher yields was achieved by Rhus laccases(RL) catalysis in water miscible organic solvents. Biomacromolecules dehydro-genative polymers(DHP) were only synthesized by fungal laccases,not by RL. The structures and the reaction mechanism were discussed to promote the understanding of the function of laccases in the process of lignin biosynthesis.

关键词： lignan laccases pinoresinol dehydrogenative polymers enzymatic mechanism

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Boundary Conditions for Combustion Field and LB Simulation of Diesel Particulate Filter

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Communications in Computational Physics 2013年第3期13卷 769-779页

作者： kazuhiro Yamamoto Department of Mechanical Science and Engineering Faculty of EngineeringNagoya UniversityFuro-choChikusa-kuNagoya464-8603 Japan

A diesel particulate filter(DPF)is a key technology to meet future emission standards of particulate matters(PM),mainly *** is generally consists of a wall-flow type filter positioned in the exhaust stream of a diesel *** is difficult to simulate the thermal flow in DPF,because we need to consider the soot deposition and combustion in the complex geometry of filter *** our previous study,we proposed an approach for the conjugate simulation of gas-solid *** is,the gas phase was simulated by the lattice Boltzmann method(LBM),coupled with the equation of heat conduction inside the solid filter ***,its numerical procedure was slightly *** this study,to reduce numerical costs,we have tested a new boundary condition with chemical equilibrium in soot combustion at the surface of filter *** on the soot oxidation rate with catalysts evaluated in experiments,the lattice Boltzmann simulation of soot combustion in the catalyzed DPF is firstly presented to consider the process in the after-treatment of diesel exhaust *** heat and mass transfer is shown to discuss the effect of catalysts.

关键词： Lattice Boltzmann method DPF heat conduction X-ray CT multiphase flow

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Unpowered Knee Exoskeleton Reduces Quadriceps Activity during Cycling

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Engineering 2018年第4期4卷 471-478页

作者： Ronnapee Chaichaowarat Jun Kinugawa kazuhiro Kosuge Department of Robotics Tohoku University Sendal 980-8579 Japan

自行车是一种环保且具有娱乐性的交通方式。为了减少自行车运动的能量消耗同时不消耗额外的能源,我们提出利用扭力弹簧对膝关节伸展进行支撑。我们开发了一个基于嵌入式扭转弹簧与交叉四杆机构的膝关节外骨骼原型机。在研究过程中,通过... 详细信息

自行车是一种环保且具有娱乐性的交通方式。为了减少自行车运动的能量消耗同时不消耗额外的能源,我们提出利用扭力弹簧对膝关节伸展进行支撑。我们开发了一个基于嵌入式扭转弹簧与交叉四杆机构的膝关节外骨骼原型机。在研究过程中,通过分析8名健康男性参与者以恒定功率骑行测试的数据,对原型机性能进行了评估。记录参与者在200 W和225 W带有加速系统的骑行训练机运动时两个腿部股直肌的表面肌电图(EMG)。然后,通过连续小波变换在时间频率上分析这些数据。在相同的骑行速度和腿部节奏下,肌电的中值功率谱频率随骑行负荷的增加而增加。在相同的骑行载荷下,外骨骼机器人可使中值功率谱频率降低。外骨骼机器人不消耗电能,不传递净正机械功,可减轻股四头肌的活动。此项基础研究可应用于骑行辅助可穿戴设备的进一步开发。

关键词：自行车骨骼设计方案产品介绍

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Predicting Tensile Properties of Friction-Stir-Welded 6063 Aluminum with Experimentally Measured Welding Heat Input

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Acta Metallurgica Sinica(English Letters) 2020年第9期33卷 1235-1242页

作者： Tianbo Zhao Yutaka SSato Hiroyuki Kokawa kazuhiro Ito Department of Materials Processing Graduate School of EngineeringTohoku University6-6-02 Aramaki-aza-AobaSendai 980-8579Japan Joining and Welding Research Institute Osaka UniversityMihogaoka11-1IbarakiOsaka 567-0047Japan Shanghai Key Laboratory of Materials Laser Processing and Modification School of Materials Science and EngineeringShanghai Jiao Tong UniversityShanghai 200240China

This work aims to develop a reliable method to predict mechanical properties of friction-stir-welded 6 xxx-series alloys with experimentally measured welding heat input. A calorimetrical method was utilized to experimentally measure the welding heat input in the friction stir welded of aluminum alloy 6063-T5. Good correlations between the input variables, i.e., welding parameters and physical properties of the materials, and the welding heat inputs obtained with experimental measurements were discovered. The welding heat input can be predicted using the empirical equation derived based on these correlations. Moreover, the results suggested that the thermal conductivities of the welded alloys affected the welding heat input significantly. Mechanical properties, including hardness and tensile properties, of friction-stir-welded aluminum alloy 6063 were in good correlation to the heat input obtained with experimental measurement. These correlations were explained by the evolution of the strengthening precipitates during welding. This work proposed a reliable new route to predict these mechanical responses through the estimation of heat input.

关键词： Heat input Friction stir welding Calorimetrical Mechanical properties Hardness

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Negative thermal expansion and phase transition of low-temperature Mg_(2)NiH_(4)

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Journal of Magnesium and Alloys 2023年第9期11卷 3338-3349页

作者： Qun Luo Qi Cai Qinfen Gu Yu Shi Bin Liu Xuan Quy Tran Syo Matsumura Tong-Yi Zhang kazuhiro Nogita Tao Lyu Qian Li Fusheng Pan State Key Laboratory of Advanced Special Steel&Shanghai Key Laboratory of Advanced Ferrometallurgy&School of Materials Science and Engineering Shanghai UniversityShanghai 200444China Materials Genome Institute Shanghai UniversityShanghai 200444China Australian Synchrotron ANSTO800 Blackburn RoadClaytonVictoria 3168Australia Department of Applied Quantum Physics and Nuclear Engineering Kyushu UniversityFukuoka 819-0395Japan Nihon Superior Centre for the Manufacture of Electronic Materials(NS CMEM) School of Mechanical and Mining EngineeringThe University of QueenslandBrisbaneQueensland 4072Australia National Engineering Research Center for Magnesium Alloy Chongqing UniversityChongqing 400044China

The negative thermal expansion(NTE) phenomenon is of great significance in fabricating zero thermal expansion(ZTE) materials to avoid thermal shock during heating and cooling. NTE is observed in limited groups of materials, e.g., metal cyanides, oxometallates, and metalorganic frameworks, but has not been reported in the family of metal hydrides. Herein, a colossal and continuous negative thermal expansion is firstly developed in the low-temperature phases of LT1-and LT2-Mg_(2)NiH_(4) between 488 K and 733 K from in-situ transmission electron microscope(TEM) video, with the volume contraction reaching 18.7% and 11.3%, respectively. The mechanisms for volume contraction of LT1 and LT2 phases are elucidated from the viewpoints of phase transformation, magnetic transition, and dehydrogenation, which is different from common NTE materials containing flexible polyhedra units in the structure. The linear volume shrinkage of LT2 in the temperature of 488-553 K corresponds to the phase transition of LT2→HT with a thermal expansion coefficient of -799.7 × 10^(-6) K^(-1) revealed by in-situ synchrotron powder X-ray diffraction. The sudden volume contraction in LT1 between 488 and 493 K may be caused by the rapid dehydrogenation of LT1 to Mg_(2)Ni. The revealed phenomenon in single composite material with different structures would be significant for preparing zero thermal expansion materials by tuning the fraction of LT1 and LT2 phases.

关键词： Negative thermal expansion Mg_(2)NiH_(4) Phase transformation In situ TEM In situ XRD

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