Komyo Kariya

Trabecular Pattern Analysis Using Fractal Dimension

Feature extraction from a digitized image is advantageous for the detection of signs of disease. In this work, we attempted to evaluate bone trabecular pattern changes in osteoporosis using the fractal dimension and the root mean square (RMS) values. The relationship between the fractal dimension and the 1st moment of the power spectrum is explored, and we investigated the relationship between the results of this analysis and the bone mineral density (BMD) value which was measured using dual-energy X-ray absorptiometry (DEXA). As a result, we were able to extract useful information, using the fractal dimension and the RMS value of the radiographs (lateral view of the lumbar vertebrae), for the diagnosis of osteoporosis. Abnormal clinical cases were separated from normal cases based on the evaluation values. Negligible correlation between the BMD value and these indexes was observed.

An improved method for digitized data reduction using an angle parameter

Abstract This paper reports an improved sequential data reduction method for digitized 2-D images. Data input into the image handling system has been the bottleneck for the construction of the system. Most of the input devices were keyboard, mouse and digitizer tablet. Recently various kinds of image input device have been developed. Especially notewrothy is the appearance of the flat bed scanner, which makes it very easy to handle a manuscript just as a copy machine. This device introduces a new input method for CAD/CAM systems in the field of printing machines and lettering machines. As almost all jobs are rapidly automated in these years, various kinds of CAD/CAM systems are introduced into these field. These devices make it possible to get various kinds of image which always have thousands of data points for each figure even though the original image is a circle. A large amount of data causes many problems for handling the images in the CAD/CAM system. In a small-size system, these kinds of large-data image sometimes exceed the system memory and stop the whole process. We propose an improved sequential method for data reduction which can control the distance between input and output data. This method also makes it possible to accept a large amount of data in a small-size system. Through several simulations, the efficiency of this improved method is shown in this paper.

Investigation of conduction mechanism in thick film resistors trimmed by the pulse voltage method

The conduction mechanism of RuO/sub 2/-based thick-film resistor (TFR) trimmed by the pulse voltage trimming (PVT) method is discussed. The surface temperature distribution barely changed when power was applied to the TFR, moreover, no current crowding was found by results of scanning electron microscopy-voltage contrast (SEM-VC). The existence of electron traps in the TFR could not be detected from the results of temperature stimulus current (TSC) characteristics. The resistance value of the TFR increased at 600 degrees C and then decreased abruptly at 800 degrees C. It was supposed, therefore, that the heat stress accumulated in the TFR during the refiring process of the TFRs was relaxed by the thermal annealing due to the PVT. Consequently, the decrease in the resistivity of the TFR, after the PVT, was quite logical, if an increase in the number of conductive paths resulted when the conductive structure was modified in the TFR. In addition, frequency resistance characteristics of the TFRs qualitatively best fit the values predicted by the metal-insulator-metal model. >

The effects of aliasing error on computed radiography in medical imaging

In computed radiography in medical imaging, the quality of the image made on the imaging plate (IP) is changed by the digitizing and printing processes. According to the sampring theorem, aliasing errors will occur when the image is sparsely sampled. We simulated these processes and measured the modulation transfer function (MTF) and aliasing error. Both an X-ray film and an IP were packed in a cassette so that X-ray film was exposed by instantaneous luminescence of the IP. Analog and digital images on clinical radiographs, such as of the chest and the foot, were obtained by this method. Both images were compared by radiologists under the usual viewing condition and with optical magnification. Results showed that the digital images were degraded with poor sharpness and had aliasing error produced by the digitizing process, but the aliasing error could not be observed on the clinical image. Therefore, a system producing sharper images will be required, although aliasing errors could increase.

The Field Effect Mobility and the Current-Voltage Characteristics of Amorphous-Silicon Thin-Film Transistors

The current-voltage characteristics of a hydrogenated amorphous silicon thin-film transistor were investigated. The computed equation for the current-voltage characteristics that incorporated gate-voltage-dependent field effect mobility and drain-voltage-dependent effective gate length was in excellent agreement with the experimental data.

Computerised education in harmony with normal lectures

Many styles of computer application in education are developing and when the application relates directly with educational contents and effects it is called CAI (Computer Assisted Instruction). Attempts have been made to develop and apply computers to individual stages of school education and in each field of special education. In this paper, after introducing the status of computer application in education (mainly CAI) in Japan, an education method is proposed which is in good harmony with essential normal lectures. The essence of education is in the lecture. The practice of CAI, it must be explained, does not lose the essence of lectures but improves education effects.

Dynamic Measurement of Physical Conditions in Daily Life by Body Area Network Sensing System

This paper shows the measurement system to monitor physical conditions dynamically in dairy life. The measurement system for physical conditions in motion must be wearable and wireless connected. Body area network sensing system (BANSS) is a kind of the system to realize the conditions. BANSS is the system constructed with host system and plural sensing nodes. Sensing node is constructed with sensors, analogue/digital convertor(ADC), peripheral interface component(PIC), memory and near field communication device(NFCD). The NFCD in this system is Zigbee. Zigbee is the most suitable to construct wireless network system easily. BANSS is not only the system to measure physical parameters. BANSS informs current physical conditions and advises to keep suitable physical strength. As an application of BANSS, the system managing heart rate in walking is shown. By using this system, users can exercise in condition of a constant physical strength.

A study of traceability and application of ISO rule for QC of blood chemical analysis

The introduction of ISO and JIS rules was tested on the standard measurement system. The quality control (QC) of blood chemical analysis is based on the WHO rule and the QC is treated by a statistical analysis method. However, the measured data have many uncertainties, so the QC according to ISO-GUM is discussed. This paper presents the result of the discussion.

Source localization of auditory magnetic fields evoked by syllables and modulated noises

Recent advances in technology and computing, such as the superconducting quantum interference device (SQUID) magnetometers and multichannel measuring systems have enabled us to noninvasively measure the magnetic fields related to the activity of neurons in the human auditory cortex. Auditory neuromagnetic fields observed after the stimulus onset and subsequent consonant/vowel transitions that occur when subjects listen to natural human speech are thought to be caused by spectral transitions or power transitions in the sound. The present study investigated whether they are caused by power transitions alone, and found that the M100 components (a deflection about 100 ms after onset of the stimulus) evoked by syllables are more prominent than those evoked by modulated noise and that the moment of the equivalent current dipoles of M100 components evoked by syllables is larger than the moment of the components evoked by modulated noise. Since the powers of both stimuli were the same, this suggests that the M100 components of auditory magnetic fields are not caused by power transitions alone. This study also suggests a method for measuring the auditory function.

Minimization of measurement points on automobile traffic flow

Abstract The acquisition of information on the relation between flow speed and jam conditions of automobile traffic flow on express ways is necessary to achieve appropriate traffic flow. It is very difficult to use a large number of measuring points on a road, so in practice a grasp of the situation is achieved by measuring the flow conditions at a small number of measuring points. This paper deals with the application of a graphical interpolation method to the minimized number of measuring points in order to estimate the spatial density field of flow concentration. The traffic flow is expressed as a compressive flow, and this model is analyzed by a nonlinear equation. The results are given by the combination of characteristic lines and the propagation of a shock wave.