The objective of this study is to establish the method to evaluate the skill level quantitatively, and to improve the skill level based on the evaluation. The nailing was performed as one of the typical and simple work operation. The operation with a right hand was assumed to be the operation of an expert. The operation with a left hand was assumed to be the operation of a non-expert. The difference between them was verified by means of the3D motion analysis equipment. The3D motion analysis enabled us to make an advice to improve the operation. Remarkable progress in the operation was found after the advice based on the3D motion analysis. It was concluded that the effective training could be made based on the3D motion analysis.

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The goal of our research is to develop a novel axial flow blood pump that only uses a hydrodynamic bearing to levitate the impeller. This axial flow blood pump has a unique structure; the center of the rotor was hollow and the blood passes through this hollow region(the enclosed-impeller). In this paper, an enclosed-impeller was designed for the axial flow blood pump. The velocity and pressure distributions in the enclosed-impeller were evaluated using computational fluid dynamics(CFD)analysis. A pressure head was calculated from the pressure distribution of each analysis and the values obtained were compared with the results of in-vitro experiments. We did not find any turbulence in the enclosed-impeller from the results of the velocity distribution. By comparing the pressure heads, the values obtained from the CFD analysis were found to be in good agreement with the in-vitro experimental data for rotational speeds in the range8, 000-12, 000rpm. A flow rate of5L/min for a100-mmHg-pressure head was achieved in the in-vitro experiments at a rotational speed of approximately9, 000rpm. The newly developed axial flow blood pump is expected to be used in implantable rotary blood pumps.

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The matsensors are often used to detect movement of a person who is unable to walk, possibly due to medication or a physical handicap, and requires assistance to keep from falling when trying to get out of bed and a person who might wander the facility unattended. The use of matsensor is critical for elderly persons to avoid injury or broken bones due to falling from bed or to quickly notify the care giver when the individual begins to wander. When the individual stands on the matsensor, it sends notification to the care giver, but if the person should fall, it will not be detected by matsensor. The ultrasonic array sensor has recently been developed which senses the distance and direction between the object and the sensor. We thought that the ultrasonic array sensor could detect when an elderly person gets out of bed by detecting the position of the head. So, we have developed an experimental system to monitor head position by processing the signal output of this ultrasonic array sensor. In our experiment, we placed the ultrasonic array sensor on the ceiling with no furniture and no one around the bed. We used five people in two test situations in which each person got out of bed13different ways; this produced two separate types of data. In conclusion, we estimate the detection rate of head position is98%and getting out of bed is85%.

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A new detection method using color cards is presented, which can detect individuals having impaired QOL, and detect individuals in high negative mood state, and detect individuals having mental troubles from healthy individuals. In this method subjects answer likeabihty of the color cards and describe impressions of the color cards as locations on the color image scale. We implemented this method to50females(40's-70's)li ving independently in local communities. The31color cards were displayed to the subjects. And then the subjects answered QOL questionnaire, Profile of Mood States, and M. I. N. I.-Screen that was the screening edition of M. I. N. I.(Mini-International Neuropsychiatric Interview). We obtained the individual features. regarding the likeability and impressions of the color cards. The discriminant functions that were composed of the individual features extracted eight subjects having impaired QOL successfully in88%and the correlation ratio was0.35, extracted five subjects in high negative mood state successfully in94%and the correlation ratio was0.43, and extracted two subjects having Major Depressive Episode successfully in82%and the correlation ratio was0.12.

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Falling is one of the most common and serious problems because advancing age has been associated with muscle weakness and deterioration of postural control system. The mechanisms contributing to age-related increases in ability of postural control and falls in the elderly remain unclear. The purpose of the stabilogram diffusion analysis(SDA)method was to study change of the mechanism of postural control between young and elderly generation. Any parameters of SDA were compared with several parameters of body sway derived from recordings of the center of pressure(COP)with the aid of a static force platform. The subjects were48healthy young volunteers(age: 18-64yeas, mean±S. D: 33. 6±14. 6years)and41 healthy elderly volunteers(age: 65-87years, mean±S. D: 77.7±4.3years). They quietly stood on a static force plat form with o pen and closing eyes for thirty seconds. The following results were indicated. 1. The elderly group was a significantly than the young group greater in the Diffusion constant Drs and the mean square critical displacement when eyes open and eyes closed. 2. On the elderly group, the correlation between SDA parameters and COP parameters was found to be greater in the closing eye condition than that in the open eye condition. 3. The correlations between diffusion coefficient and the range o f anterior-posterior was greater than the correlations between the diffusion coefficients and the range of medio-lateral. Thus, the muscle of the tibialis anterior and the planter muscles was suggested.

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