Concerning a mesurement of finger motion with a view to controlling of a robot hand and an artifical arm, we studied how to distinguish a finger motion by EMG with a continuous motion. A distinction system is a neural network. However, a process in front of input to neural network, so-called a pre-process, is important before everything in the extraction of a characteristic of EMG with each finger motion.
In this study, as a result of the application of a principal component analysis by way of pre-process, we could find a characteristic in computed eigen vector. As a result of experiment of distinction between each fingers concerning a continuous motion of finger, we could confirm an effectiveness of a proposed system.

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Recently videofluorography has been used for evaluation of swallowing function in rehabilitation field. But it is not easy to evaluate swallowing disorder simply. And it has problems of exposure for daily use. We have proposed a measurement method of swallowing using bioelectrical impedance method (Impedance Pharyngography, IPG) which has advantages of easy handle and non-invasive measurement. Appropriate electrode positions have been determined. The waveforms of IPG can be obtained with some extent reproducibility. The change of neck electrical impedance in pharyngeal phase is mainly caused by the changes of equivalent cross sectional area of near epiglottis. The possibilities of applications for clinical diagnosis have been shown.

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This paper presents a recognize and visualize methods of human motion patterns in walking using an accelerometer for automatic emergency call systems for seniors. The recognition is realized by these two steps: (1) extraction of a spectrum of the acceleration measured by a accelerometer attached on the waist that represents the gait cycle (cycle of foot steps) through dynamic threshold processing; (2) classification of the motion based on the observed fact that the intensity of the spectrum increases when the human motion changes from 'stand', 'walk' to 'run'. Moreover, the result of the recognition is visualized as a real-time, privacy-protected animation, where a character animation generator, our previous study work, is used that a character is controlled by qualified motion parameters.

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The number of the patients of the circulatory disease is increasing by increase in elderies population. The elderies has many chances to test the autonomic function because of the diagnosis or treatment of the circulatory disease. One of the testing method of the autonomic function is to analyze the heart rate variability due to postural change. The postural change involves the risk of the syncope. In the standing posture, the workload is large for the elderies. In this paper, the evaluation method of the autonomic function with a light workload is proposed for the elderies. The initial heart rate increase on standing is evaluated using the impulse response function deriving from the heart rate during supine position. The autonomic function during standing following a supine is evaluated by the heart rate variability during standing following a sitting. We propose a new method in comparison with the head-up-tilt test. The parameters of the autonomic function derived from our method are highly correlated to those derived from the head-up-tilt test. Our method is adequate for evaluation of the autonomic function of the elderies.

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In recent years, there has been a growing demand for optimal X-ray photography of elderly persons without producing physical pain or mental stress. The author therefore presents a new technique for creating pseudo image contrast by computer to prevent repeated taking of X-ray photographs, and an experimental formula to estimate photographic density by fluorescence intensity and the real-time wave form of X-ray tube voltage. It was found that the pseudo image contrast of an acrylic phantom estimated by this technique matched well with the photographic density of the actual X-ray photograph.

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We have developed a transfer aid system for the elderly who need assistance in moving from a bed or a chair. We studied a comfortable posture for the elderly at an initial phase of standing. The subjects were divided into two age groups, the young group (mean 29.6 years), the elderly group (mean 65.0 years). In this experiment, the subjects were allowed to stand up from a chair by changing the angle of their ankles at the initial phase of standing. Sagittal plane kinematics, surface electromyographic (EMG) signals at lower limbs and ground reaction forces were measured using a 3 dimension motion analyzer, when each subject stood up from a chair. From the experimental results, when the initial angle of ankles was about 70 degrees and initial angle of the trunk was about 45 degrees while standing from a bed, the comfortable transfer aid motion was determined. From the above results, We ware designed a transfer aid system by using of a MH (Metal Hydride) actuator which is light, powerful, no-vibratile and silent. The transfer aid could enable a comfortable posture thanks to the help of the chest and knee pads at the initial phase.

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The purpose of this study was to investigate a traffic environment that can reduce traffic accidents of elder walker. We focused on the relationship between traffic accidents and elder person's spatial attention. In this paper, an adolescent subject's and an elder subject's pointing movement to a visual target was measured in three conditions. Condition 1: Only the target was presented. Condition 2: Auditory stimulation was added at a location the same distance from the center as that of the targets but in the opposite direction. Condition 3: Auditory stimulation was added at the same location as the target. The targets were placed in extra working space with the distance of 15 meter from a subject to the targets. In adolescent subjects, results showed that in Condition 3, latency was shorter and the error rate of pointing movements was lower than in the other conditions, In elder subjects, results showed that in all Conditions, ignore ratio to peripheral targets is higher than adolescent subjects. Nevertheless, in condition 3, more ratio was lower than in the other conditions. These results suggest that, it is possible to draw elder walker's spatial attention and to control spatial attention by auditory stimulation.

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This purpose is a cooperative work on a welfare agent robot system (i.e. a walking support robot system) which is not only in cooperation with a human but also in cooperation with each robot. To realize this cooperative work, we propose a multi-agent algorism; each robot decides own movement to make a formation (line style or circle style). We construct the system using the same robot control part made by Fuzzy Associative Memory Organizing Units Systems (FAMOUS) and Chaotic FAMOUS (CFAMOUS). This control part drives following both (1) and (2).
(1) The robot determines own movement by general instructions of a human and situation of its circumference without detailed instructions of a human.
(2) The robot creates new knowledge to avoid a little trouble, when the robot cannot cope with the trouble by using existing knowledge without instructions of a human.
Experimental results show the effectiveness for the welfare agent robot system.

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ABSTRACT We have proposed a Tripolar Electrode Stimulation Method (TESM) which may succeed in narrowing the stimulation region and continuously moving the stimulation site for cochlear implants. The TESM stimulates the auditory nerve array through lymph liquid using the 3 adjacent electrodes which are selected among the electrodes of an electrode array. The currents from the two electrodes on both sides are emitted and a central electrode receives them. The current received by the central electrode is made equal to the sum of the currents emitted from the electrodes on both sides. In this paper, the electric intensity profiles produced by the TESM and the monopolar stimulation were measured in a human cadaver cochlea and in a saline solution. As a result, in the TESM, the electric intensity profile produced in the human cadaver cochlea was about the same as that in the saline solution. In monopolar stimulation, the electric intensity profile was broader than that of TESM in a human cadaver cochlea.

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We developed the conductive ink using silver (Ag) -copper (Cu) solid solution powder and investigated an ionic migration phenomenon of the conductive ink. The conductive ink is made by dispersing the powder in phenol resin. This powder has a shell structure. The Ag concentration at the surface of the powder is higher than an average Ag concentration in the bulk, and Ag concentration decreases toward inside of the powder. The Ag concentration of about 85 wt% in the Ag-rich phase dose not strongly depend on the average Ag concentration, and the thickness of Ag-rich phase increase with the average Ag concentration. Though this ink includes Ag, in which ionic migration occurs most easily, and Cu, which is oxidized easily, the migration occurrence of this ink including the powder with Ag of 5 wt% was similar to that of Cu conductive ink and Ag migration was not observed.

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This paper describes the neuromagnetic estimation of multiple sources and a computer simulation study based on a 3-D magnetic measurement. The magnetic distribution perpendicular to the scalp was not helpful for estimating the location and number of sources, owing to the lack of a dipole pattern. By referring to the magnetic distribution tangential to the scalp, however, two sources could be clearly discriminated in a spherical head model. It was found that this magnetic measurement tangential to the scalp could provide information on new constrained conditions for calculation of the inverse problems with multiple sources.

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The electrical conduction mechanism of composites below the percolation threshold has been generally discussed with the hopping conduction model. In this article, the electrical conduction mechanism of carbon black-polyethylene composites below the percolation threshold is discussed based on the frequency dependence of conductivity in the range of 20 Hz to 1 MHz. There are two components for observed ac loss current. One is independent of frequency and becomes prevalent in low frequencies just below the percolation threshold and under high electric field. The other is proportional to the frequency of applied ac voltage in high frequencies and its origin is not clear. These results support the conclusion that the electrical conduction mechanism below the percolation threshold is tunneling.

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Planar self-shielded gradient coils have been designed using a Hankel-Bessel expansion of magnetic fields and the minimum inductance formulation. We found that linear gradient fields in high accuracy can be obtained by positioning field-setting-points on the imaging spherical surface. The obtained gradient field linearity of the shielded gradient coils is within 2% at the imaging spherical region and the residual external fields are less than 1% of the fields generated by non-shielded coils.

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The propagation distortions have been numerically calculated for the various signals based on a nonideal square pulse along an exponential microstrip taper. The numerical calculations have been performed for the propagation distortions of the various signals obtained by taking compulsorily the cut-off of the frequency components higher than some cut-off frequency in spectra of the nonideal square pulse. The frequency dependence of the distortions of those signals of low-pass spectra has been studied in detail. The mechanism in the pulse distortions has been clarified. The large and sharp spikes in the distorted pulse shape are caused by the delay time owing to the phase velocity in the high frequency region related with the slope part in the curve of the propagation time τ L (ω)/2. These magnitudes depend on the magnitudes of spectra of the signal in that frequency region. The plateau distortions in the center and tail parts of the distorted pulse shape are mainly caused by multiple reflections in the low frequency region below the angular frequency at the first zero point of the reflection coefficient and exist in the terms of τL(0)/2-μ_??_t_??_3τL(0)/2+μ. The influence of the length of the taper on the distorted shape has been clarified.

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The ozone generator's function is used to make healthier and cleaner human environment. The deodourizing and sterilizing effects of ozone have been accepted in the field of water and wastwater treatment, medical activity, and food market. The purpose of development is to design a compact sized ozone generator such as used in a refrigerator. In this case, it must have a simple construction, a safe operation and a stable discharge condition. It seems to be satisfied by using a ceramic transformer as a high voltage power supply and needles to a plane electrode. The ceramic transformer has such characteristics that higher step up ratio and lower input impedance are obtaind against the higher load impedance. This gives the ozone generator merits of self current regulation and over current protection without any regulation circuits. There is a benefit in fact that voltage across the electrode drops when impedance between electrodes becomes low. In this paper, the ozone generator employing a ceramic transformer and a 4 times voltage rectifier will be described.

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