This paper proposes a noninvasive method for estimating the dynamic characteristics of arterial walls using pulse waves measured in various parts of the body by a foil-type pressure sensor. The sensor not only has high sensitivity and flexibility but also features the ability to continuously measure the alternating-current component of pulse waves. These capabilities make it suitable for estimating the dynamic characteristics of arterial walls. In this paper, a foil-type pressure sensor was employed to measure pulse waves based on the tonometry approach, and a method of estimating changes in arterial viscoelastic indices was proposed based on the measured pulse waves and photoplethysmograms. In order to accurately measure blood pressure, first, we examined suitable mechanical forces to the sensor, and found that values of 5-25[N] yielded the best performance. We then estimated the arterial viscoelastic indices of a radial artery and a dorsal pedis artery when mechanical pain stimuli were applied to the subjects. The results suggested that the estimated indices can be used to quantitatively assess vascular response caused by sympathicotonia. We thus concluded that the proposed method enabled noninvasive measurement of pulse waves in the dorsal pedis artery and estimation of arterial viscoelastic indices.

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We report on a technique to construct an ultrasound calcification phantom using wires. Employment of the proper angle of the measurement plane to a wire target can adjust its effective size to that of a mass target. To acquire this angle of the measurement plane we compared the scattering cross-sections of 0.2, 0.1, 0.05 and 0.03 mm diameter copper wires, and copper cylinders that are 0.2 and 0.1 mm in size. The experiments were conducted using a commercial ultrasonographic device with a 7.5 MHz linear array probe. The scattering cross-section of a wire is severely reduced as the angle of the measurement plane to that wire decreases. At a depth of 2 cm the scattering cross-sections of the 0.2 and 0.1 mm copper cylinders are equivalent to the scattering cross-section of a 0.1 mm diameter copper wire, when the measurement plane angles to the wire are 87.6 and 87.0 degrees for the 0.2 and 0.1 mm copper cylinders, respectively. This result indicated that the employment of the proper angle of the measurement plane can adjust the effective size of a wire target to the size of a mass target, and consequently fulfills the requirements for use as a calcification phantom.

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Our group previously reported the application of a flow-through type pH/CO₂ sensor system designed to evaluate the metabolic activity of cultured cells. The sensor system consists of two ion-sensitive field effect transistors (ISFETs), an ISFET to measure the total pH change and an ISFET enclosed within a gas-permeable silicone tube to measure the pH change attributable to CO₂. In that study, we used the system to quantitatively analyze metabolic switching induced by glucose concentration changes in three cultured cell types (bovine arterial endothelium cell (BAEC), human umbilical vein endothelium cell (HUVEC), and rat cardiomuscle cell (RCMC)), and to measure the production rates of total carbonate and free lactic acid in the cultured cells. In every cell type examined, a decrease in the glucose concentration led to an increase in total carbonate, a product of cellular respiration, and a decrease of free lactic acid, a product of glycolysis. There were very significant differences among the cell types, however, in the glucose concentrations at the metabolic switching points. We postulated that the cell has a unique switching point on the metabolic pathway from glycolysis to respiration. In this paper we use our sensor system to evaluate the metabolic switching of human embryonic kidney 293 cells triggered by glucose concentration changes. The superior metabolic pathway switched from glycolysis to respiration when the glucose concentration decreased to about 2 mM. This result was very similar to that obtained in our earlier experiments on HUVECs, but far different from our results on the other two cells types, BAECs and RCMCs. This sensor system will be useful for analyzing cellular metabolism for many applications and will yield novel information on different cell types.

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The maximum cross-correlation coefficient ρ_max between blood pressure variability and heart rate variability, whose frequency components are limited to the Mayer wave-related band, is a useful index to evaluate the state of the autonomic nervous function related to baroreflex. However, measurement of continuous blood pressure with an expensive and bulky measuring device is required to calculate ρ_max. The present study has proposed an easier method for obtaining ρ_max with measurement of finger photoplethysmography (PPG) only. In the proposed method, independent components are extracted from feature variables specifying the PPG signal by using the independent component analysis (ICA), and then the most appropriate component is chosen out of them so that the ρ_max calculated from the component can approximate its true value. The results from the experiment with a postural change performed in 18 healthy subjects have suggested that the proposed method is available for estimating ρ_max by using the ICA to extract blood pressure information from the PPG signal.

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Requirement for monitoring the state of the elderly in care facilities is increasing year by year and the increase in accidents involving them becomes great concern. In this paper, an ultra-wideband impulse-radio monitoring sensor is suggested which focuses on the bed state most critical to the elderly that need the assistance immediately. Employing our developed state estimation algorithm, various states can be detected that includes sleeping in bed, sitting up in bed and going in and out from the room. The measurements were conducted in a room assumed the care facilities and the performance is investigated where various scenarios are considered. The measurement result shows that the detection rate is more than 91%.

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A micro Electret Condenser Microphone (ECM) fabricated by Micro Electro Mechanical System (MEMS) technology was employed as a novel apparatus for human pulse wave measurement. Since ECM frequency response characteristic, i.e. sensitivity, logically maintains a constant level at lower than the resonance frequency (stiffness control), the slightest pressure difference at around 1.0Hz generated by human pulse wave is expected to detect by MEMS-ECM. As a result of the verification of frequency response of MEMS-ECM, it was found that -20dB/dec of reduction in the sensitivity around 1.0Hz was engendered by a high input-impedance amplifier, i.e. the field effect transistor (FET), mounted near MEMS chip for amplifying tiny ECM signal. Therefore, MEMS-ECM is assumed to be equivalent with a differentiation circuit at around human pulse frequency. Introducing compensation circuit, human pulse wave was successfully obtained. In addition, the radial and ulnar artery tracing, and pulse wave velocity measurement at forearm were demonstrated; as illustrating a possible application of this micro device.

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This paper proposes a method for estimation of a body temperature by using a relation between the upper arm temperature and the atmospheric temperature. Conventional method has measured by armpit or oral, because the body temperature from the body surface is influenced by the atmospheric temperature. However, there is a correlation between the body surface temperature and the atmospheric temperature. By using this correlation, the body temperature can estimated from the body surface temperature. Proposed method enables to measure body temperature by the temperature sensor that is embedded in the blood pressure monitor cuff. Therefore, simultaneous measurement of blood pressure and body temperature can be realized. The effectiveness of the proposed method is verified through the actual body temperature experiment. The proposed method might contribute to reduce the medical staff's workloads in the home medical care, and more.

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In order to solve nonlinear differential equations concerning with the spinal stretch reflexes in pendulum test, mutually synchronized values of angle, angular velocity and angular acceleration in the knee-joint are frequently used as their initial ones. In this study, we propose a method which can detect both angle and angular acceleration in the knee-joint at the same time by simple operations on the outputs of two accelerometers. Here, the principle of knee-joint motion detection, evaluation of amplitude accuracy in measured waveforms, that of synchronization accuracy are described in this order.

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To realize the ubiquitous eating habits monitoring, we proposed the use of sounds sensed by an in-ear placed wireless wearable microphone. A prototype of wireless wearable in-ear microphone was developed by utilizing a common Bluetooth headset. We proposed a robust chewing action recognition algorithm which consists of two recognition stages: “chew-like” signal detection and chewing sound verification stages. We also provide empirical results on other action recognition using in-ear sound including swallowing, cough, belch, and etc. The average chewing number counting error rate of 1.93% is achieved. Lastly, chewing sound mapping is proposed as a new prototypical approach to provide an additional intuitive feedback on food groups to be able to infer the eating habits in their daily life context.

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This study introduces a novel technique for estimating visual field by using overlapped fixation patterns obtained by amounts of displacement in voluntary eye movements during searching-tracking trials, as an alternative screening medical device for visual field examination. Proposed system was evaluated by glaucoma patients, in order to study whether or not the proposed system can be used as a visual field detection device for screening. As a result, the proposed system detected the visual field abnormality to a certain extent. However, there were some cases that detection of Mariotte blind spots was inaccurately performed. The experimental results revealed that there was room to reconsider our understanding regarding the effect of ptosis, overlapped with eye sight as well as calibration of the display position to the correct location to be examined. Results of the evaluation experiment indicated that this proposed system has a potential to be used as a visual field examination device for screening.

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This paper presents a robotic training system that can exercise the user without bodily restraint, neither markers nor sensors are attached to the trainee. We developed the robot system that has a total of four mounted components: a laser sensor, a camera, a cushion, and an electric motor. This paper have showed the method used for determining whether the trainee was bending forward or backward while walking, and the extent of the tilt, using the recorded image of the back of the trainee's head. A characteristic of our software algorithms has been that the image was divided into 9 quadrants, and each quadrant undergoes Hough transformation. We have verified experimentally that by using our algorithms for the four patterns of forward, backward, diagonally, and crouching, the tilt of the trainee's body have been accurately determined. We created a flowchart for determining the direction of movement according to experimental results. By adjusting the values used to make the distinction according to the position and the angle of the camera, and the width of the back of the trainee's head, we were able to accurately determine the walking condition of the trainee, and achieve early detection of the start of a fall.

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An improved bi-mesa structure optimized for resonator mounting is proposed. To evaluate mounting influences, the frequency differences between clamp and free X-edge conditions are calculated using a two-dimensional finite element method in the X-Y' region. When the outer mesa height was lower than 20% of the thick area, the frequency differences are less than 10% of standard-type bi-mesa resonator values. These results indicate that the improved bi-mesa structure has good separation from the mounting influences.

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In this study, a stochastic detection method of failure of machines based on the changing information of not only a linear correlation but also the higher order nonlinear correlation is proposed in a form suitable for on-line signal processing in time domain by using a personal computer, especially in order to find minutely the mutual relationship between sound and vibration emitted from rotational machines. More specifically, a conditional probability hierarchically reflecting various types of correlation information is theoretically derived by introducing an expression on the multi-dimensional probability distribution in orthogonal expansion series form. The effectiveness of the proposed theory is experimentally confirmed by applying it to the observed data emitted from a rotational machine driven by an electric motor.

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An interactor matrix plays several important roles in the control system theory. In this paper, we present a simple method to derive the right interactor for tall transfer function matrix using Moore-Penrose pseudo inverse. By the presented method, all zeros of the interactor lie at the origin. Moreover, the interactor by the proposed method has all-pass property in the discrete-time. The method will be applied to the inner-outer factorization which will be independent on the choice of the interactor.

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In this paper, we propose a method to detect perceptual continuous curves in a binary image including discontinuous curves and noises based on perceptual grouping factors. Firstly, making a Delaunay diagram from a binary image, adjacency relation is obtained. Secondly, the method selects a Delaunay edge as the starting line and connects a certain number of points. When the points have maximum evaluation value based on perceptual grouping factors, they construct an appropriate partial curve. Evaluation value of an appropriate partial curve is added to Delaunay edges selected by it. Finally, Delaunay edges that have high evaluation value are extracted. Experimental results show that proposed method has yielded results that are similar to visual curves and better than conventional methods.

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This paper proposes the improved eigen-decomposition template matching. The eigen-decomposition template matching is a method to detect the displacement and the rotational angle more accurately than the traditional rotational correlation matching such as the Cross-Correlation method. The proposed method calculates the correlation by matching the images which is determined by eigen decomposition of the template image to the input image instead of matching the template image to the input image directly. Furthermore, this paper proposes the method to detect the displacement and rotational angle even if the input image includes the large displacement translation and the intensity variations. The experimental results show that the proposed method can detect the displacement and rotational angle more accurately than the previous method for the image with a noise and an illumination variance.

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A highly sensitive inspection algorithm is proposed that extracts defects in multidimensional vector spaces from multiple images. The proposed algorithm projects subtraction vectors calculated from test and reference images to control the noise by reducing the dimensionality of vector spaces. The linear projection vectors are optimized using a physical defect model, and the noise distribution is calculated from the images. Because the noise distribution varies with the intensity or texture of the pixels, the target image is divided into small regions and the noise distribution of the subtraction images are calculated for each divided region. The bidirectional local perturbation pattern matching (BD-LPPM) which is an enhanced version of the LPPM, is proposed to increase the sensitivity when calculating the subtraction vectors, especially when the reference image contains more high-frequency components than the test image. The proposed algorithm is evaluated using defect samples for three different scanning electron microscopy images. The results reveal that the proposed algorithm increases the signal-to-noise ratio by a factor of 1.32 relative to that obtained using the Mahalanobis distance algorithm.

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Novel adaptive PSO (particle swarm optimization) algorithms called OPSO (online PSO) and εPSO are proposed. These algorithms are designed to prevent increasing of calculation cost in order to embed into online systems, and they have high adaptive performances to the environmental changes. Then, the efficiency of the proposed PSO algorithms are demonstrated by numerical simulation and the online identification of an actual dynamic system.

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In order to extend circuit theory of multi-band matching networks, a lumped triple-band transformer for pure resistance loads is introduced. First, the circuit theory and the design equations of the proposed circuit are reported. Next, a numerical example of the proposed circuit is presented to verify the validity of the design equations.

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This paper describes the control method of a mouse-pointer in multi-monitor display environment by the proposed head tracking using infrared sensor of home gaming console, Wii. When an operator finds a mouse-pointer at the time of VDT work resumption, the proposed system is able to lighten his botheration.

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In this research we study a supporting method for making recipes with control of nutritional elements. In order to make new recipes we use existing recipes, food material information and information of nutritional elements. We show effectiveness of the proposed method by some experiments.

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