This paper represents the characteristics of the contact compliances of a soft material measured with a piezoelectric vibrometer. The transducer used here is designed to operate with a piezoelectric disk employed as a driver unit, and it is convenient for handling. The vibration modes of the piezoelectric vibrometer placed on the soft materials with a finite thickness were studied experimentally and theoretically. In such a system, the differential equation of motion is obtained from a single-degree-of-freedom system. In the presentation of the solutions to different cases involving the single-degree-of-freedom system, it is conventional to express the relationships in terms of the parameters of a resonant frequency, mass, and stiffness. However, in analysis problems we have not a quantitative understanding of the characteristics, since such a parameter is closely connected with the physical properties of a soft material. Therefore, the characteristics of the contact compliance were analyzed with an introduction of a dimensionless frequency factor and mass factor. The actual values measured in experiments were consistent with the results obtained with theoretical analysis.

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This paper proposed a recording and processing method for voluntary movement of a hand which pursued a visual moving target on two dimensional screen. We investigated 33 subjects categorized into 4 groups of 11 normal adults, 9 normal aged persons, 8 patients with cerebellar ataxia and 5 patients with Parkinson's disease. Based on an error criterion we extracted the following feature parameters: standard deviation of time shifted error time series (horizontal component), mean frequency in the low frequency band (horizontal component), skewness of the frequency distribution in the low band (vertical component) amount of the periodogram in the high frequency band (vertical component). Automatic classification of each subject into one of the 4 groups was implemented based on a nonlinear discrimination function using the extracted feature parameters. A perfect classification was obtained for normal adults, however the classification among the rest 3 groups was successful in 80% accuracy

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In general an anatomical joint is not a hinge joint. Then the center of rotation is not a fixed point, and usually it moves with joint motion. In other words, the anatomical joint motion is composed of translation and rotation. Instantaneous center of rotation (ICR) is useful to describe such joint motion. In this paper, ICR of temporomandibular joint motion was measured. To calculate the ICR, differentiation process is necessary. But it is very sensitive to error of landmark position. Therefore a new algorithm which utilizes data smoothing was proposed. This method is based upon a sufficient amount of data which can be collected using, for example, a photo-sensitive semiconductor and light emitting diodes. Locus patterns of ICR deviated in each phase of habitual opening and closing. But generally speaking, ICR of closing was located under the condyle and it moves from posterior to anterior like an arc. Relation between location of ICR and specific sliding was discussed, and experimental results of ICR were in agreement with the results of discussion.

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This paper describes an automated classification algorithm of RBC's morphological abnormalities, which is one of the examinations of the blood cell differentials. As there are many RBCs in the image (which is called multi-object pattern), one of the important problems for this automation is to develope the segmentation of the multi-object pattern. We developed a new method of the segmentation of the multi-object pattern, which was done only by the local operations based on the wave propagation method. Feature extraction is done only by the local operations, too. Moreover, we developed a logic to detect various kinds of morphological abnormalities by the partition of multidimensional space, which is defined by the feature parameters of RBC's. Classification rate of morphological abnormalities by this method is 92.6%.

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The effect of valve orientation on the hydraulic characteristics of aortic valve prostheses was studied by using a total mock system of human left heart and aorta. The system replicated the geometry of left heart and aortic arch having a pertinent hydraulic load of the systemic circulation so that the flow process simulated a physiological pulsatile condition. Simultaneous flow visualization study was carried out to investigate the dependence of valve orientation on the flow development in the aortic arch. Five different tilting disc valves, Björk-Shiley spherical, Beörk-Shiley convexo-concave, Björk-Shiley monostrut, Medtronic-Hall, and Omni-Science valves, each having an annulus diameter of 25mm, were evaluated as to how the valve insertion should be oriented. Total hydraulic evaluations regarding systolic energy loss, resistive coefficient as well as the turbulent flow formation suggested that the major orifice of these valves should be oriented towards the aortic outer curvature. The outer curve orientation provided low systolic energy loss and low resistive coefficient. These findings were found to be in good agreement with the clinically and empirically arrived approvals of valve orientation.

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In the present study we examined the effects of preceding stimuli and the stimulation side on the auditory evoked fields and potentials associated with selective attention to the stimuli. In the field responses measured at the contralateral side to the stimulated ear the peak amplitude was smaller when the relevant and preceding stimuli were identical, i. e., at the same ear, than when they were different, i. e., at different ears. Attention effect was observed in the potentials as a negative shift, which was affected strongly by whether the preceding stimulus was identical or not, but little affected by whether the preceding stimulus was attended or not. It is suggested that separating the responses into those whose preceding stimulus is identical to the relevant stimulus and those whose preceding stimulus is different is necessary when attention effect is examined. In the field responses, however, the above attention effect was less clear than in the potentials. Significant differences of the peak latency were observed between the field responses in the right and left hemispheres. The peak latency in the contralateral responses to the stimulated ear was shorter than that in the ipsilateral responses.

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In this study, we programmed neuromuscular stimulation data for the functional electrical stimulation (FES) to control the paralyzed elbow movements.
The activities of the elbow flexors and extensors during movements of the elbow flexion and extension in normal subjects were analyzed by electromyography (EMG) and the following results were observed.
1) In the elbow flexors, all muscles were active during both flexion and extension of the elbow.
2) In the elbow extensors, the triceps brachii was almost inactive except at maximum extension of the elbow.
Based upon EMG analyses, neuromuscular stimulation data for FES were programmed. With these data, we tried to control elbow movements in two C4 quadriplegics by FES. Consequently, the following results were obtained.
1) The elbow movements, which were nearly the same movements at EMG analysis, were reproduced by FES.
2) Movements of the elbow flexion and extension were controlled when the forearm was set on the balanced forearm orthosis (BFO).
3) With BFO and the respiration-controlled FES system, they were able to obtain some activities of daily living, such as drinking canned juice, by means of simultaneous control of movements of the elbow, wrist and finger.

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Distribution of segment deviation over precordial chest surface was coarsely depicted by making use of electrocardiogram from ten or 20 lead points. This was made possible through supplementing a commonly used two channel ambulatory recorder with a specially designed adapter. That electrocardiographic leads are switched at every twelve seconds by a circit. So that that they are recorded on the same intermittently. Thus, on using one recorder ST deviation of ten lead points were recorded on using two recorders that of 20 lead points were recorded. Lest being misled by non-pathognomonic ST deviation due to postural changes, paralleled recording of the posture was achieved by means of posture sensor included is the adapter. By applying this ambulatory mapping electrocardiogram system to one patient with ischemic cardiac conditions, it was suggested that recording of ST segment from ten or possibly lead points and depicting ST deviation mapping, instead of two or three lead points in customary use, is desirable for detection and making diagnosis of ischemic ST changes on the precordial chest.

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