• Applied Microscopy
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• v.45 no.1
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• pp.1-8
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• 2015

We have developed a new HD-2700 (Hitachi High-Technologies Corp., Japan) scanning transmission electron microscope (STEM) that includes an automatic aberration correction function, and a large-solid-angle energy-dispersive X-ray spectroscopy detector that enables high-resolution and sensitive analysis. For observation with atomic resolution, using spherical-aberration-corrected STEM, in order that satisfactory performance of the device can be achieved readily, and within a short time, irrespective of the operator's skill level, a spherical-aberration-correction device with an automatic aberration-correction function was developed. This automatic aberration-correction function carries out the entire correction-related process (aberration measurement, selection and correction) automatically, with automatic selection of the aberrations that require correction, and automatic measurement of the appropriate corrections.

• Journal of radiological science and technology
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• v.28 no.2
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• pp.111-115
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• 2005

The quality of image from the system that creates medical images by using X-ray depends on the various different reasons such as the X-ray generator, the subject and the image transmission medium. In other words, thereare various factors existing that can influence on the quality of image from the moment when the X-ray is generated and until the final image is created. Therefore, the operator who creates images at the clinical site should make continuous evaluation and observation from the final image. There are various methods of evaluating the medical images, but it is assumed that the MTF measurement method can be suitable for measuring actual or effective resolution. So in this study, the MTF measurement method by using X-ray film has been avoided and the MTF features according to the deterioration of the X-ray system have been measured by using the software (the program used Borland C++ builder software and LEAD tools software) that can measure the MTF of the digital medical images. As the result of this measurement, it has been found out through the MTF graph that the resolution and sharpness from the old x-ray generator with a many years of using and many numbers of times of using were deteriorated for the quality of image comparing to those from the new system. Also a simple and easy measurement method for the MTF from the digital medical images can be obtained in this study.

• Proceedings of the Korean Society of Medical Physics Conference
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• 2006.08a
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• pp.78-78
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• 2006

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.18 no.4
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• pp.111-116
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• 2018

In this thesis, the range of motion of the joint was measured using a flexible sensor without using a goniometer, and the measured values were transferred to a smart device. Current range of joint motion measurement is measured by a person using a goniometer. Since the method of measuring by a person is different according to the measuring method and position of the measuring person, it is difficult to make consistent measurement, and an error may occur. The sensor for measurement is a flexible sensor that measures the resistance value that changes according to the movement of the joint. The sensed value can be transmitted to the smart device wirelessly through the ROM sensor node. Also, the sensed analog values were converted to digital values using an ADC. The converted value can be transmitted to the smart device wirelessly through the sensor node. The developed ROM measuring device can perform more consistent measurement than the measurement using general articulator and real time monitoring by interlocking with smart device, so that rapid diagnosis according to the movement of the joint can help the patient's rapid treatment and rehabilitation medical advancement will be.

• Progress in Medical Physics
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• v.10 no.1
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• pp.9-15
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• 1999

The oxygen saturation of blood can be measured by the difference absorption in optical spectra of Hb and Hb0$_2$, as the well known previous study. In this study we developed the non-invasive oxygen measurement device for diagnosis of peripheral vascular disease in lower extremity using infrared and red LED which produce a peak spectral emission at a wavelength of 660 nm, and 940 nm. To evaluate the clinical application of the oxygen measurement device, we performed lower extremity study to measure the oxygen changes in response to physiological changes within biological tissue. The results showed that oxygen saturation of blood in biological tissue can be monitored from the separation arrangement light source and detector.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2021.05a
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• pp.470-473
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• 2021

In this study, we developed the biometric ultrasound transducer, residual thickness measurement algorithm and optimized ultrasound operation methods to diagnose precise conditions of implanted medical prosthetic material inserted during total hip artificial joint replacement. In detail, ultrasound transducers having 8 MHz and 20 MHz center frequencies with similar sensitivity and bandwidth were fabricated to measure various thicknesses of commercial polyethylene-based artificial hip liners, resulting in a comparative analysis of signal-to-noise ratio and axial resolution to conduct an optimization study of ultrasound operations in vivo.

• Journal of Biomedical Engineering Research
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• v.16 no.3
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• pp.301-308
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• 1995

A high-precision pre-amplifier is designed for general use in EEG measurement system. It consists of signal generator, signal amplifier with a impedance converter, shield driver, body driver, differential amplifier, and isolation amplifier. The combination of minimum use of inaccurate passive components and the appropriate matching of each monolithic amplifiers results in good noise behavior, low leakage current, high CMRR, high input impedance, and high IMRR. The performance of EEG pre-amplifier has been verified by showing the typical EEG pattevn of a nomad person through the clinical experiments.

• Proceedings of the KOSOMBE Conference
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• v.1992 no.05
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• pp.79-81
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• 1992

This paper describes the design of an adaptive closed circuit anesthesia controller based on a multiplexed mass spectrometer system. The controller deals with measurement deterioration caused by measurement delay and rise time through a tong catheter as well as long sampling times due to the multiplexed measurements. Measurement data is extrapolated between sampling periods to increase the estimation convergence rate. A multiple-step-ahead predictive control algorithm is used to calculate intermediatc control inputs between sampling intervals. Simulations are used to validate the designed controller.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.6 no.8
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• pp.27-34
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• 1983

Bioelectrical measurement has long been an important area in medical researches and practices, and contributed valueable data to the field of human engineering. In particular, the measurement of EEG has been widely used for the study of brain function as well as for the diagnosis of various brain disorders. The present study tried to improve conventional measurements of EEG in that FFT algorithm with microcomputer machine language was applied to facilitate the computation of various aspects of the EEG.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.33 no.6
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• pp.643-647
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• 2007

Purpose: The purpose of study was to investigate the correlationship between lip canting change and occlusal canting change after bimaxillary orthognathic surgery, and the ratio of lip canting change and occlusal canting change after the surgery. Patients and methods: The subjects for this study was obtained from a group of 25 patients who took bimaxillary orthognathic surgery for occlusal canting correction at the Department of the Oral and Maxillofacial Surgery, Samsung Medical Center in Seoul, Korea between January 2000 and December 2005 and a patient's chart had to contain a resting frontal facial photograph in natural head position and a corresponding PA cephalogram in occlusion on the same day before the surgery and post-op 6 months later. The lip canting change was assessed with the angle each labial commissure and the bipupilary reference line. And, the occlusal caning change in the frontal plane was assessed with the angle between the each maxillary first molar occulasal surface and the bi-frontozygomatic suture reference line. Results: In angular measurement, average occlusal canting change was $3.09^{\circ}$ and standard deviation was $1.05^{\circ}$, average lip canting change was $1.56^{\circ}$ and standard deviation was $1.05^{\circ}$. In linear measurement, average occlusal canting change was 2.41mm and standard deviation was 2.75mm, average lip canting change was 1.18mm and standard deviation was 0.43mm. Lip canting correction ration to occlusal canting correction was 51.5(${\pm}8.4$)% in angular measurement and 48.8(${\pm}9.1$)% in linear measurement. Under Pearson's correlation analysis, Pearson's correlation coefficient was 0.869 in angular measurement and 0.887 in linear measurement(p-value < 0.01). High correlationship was shown between occlusal canting change and lip canting change. Conclusion: First, Bimaxillary orthognathic surgery can correct lip canting as well as occlusal canting. Second, The average amount of lip canting correction is $51.5{\pm}8.4%,\;48.8{\pm}9.1%$ of occlusal canting correction in the study.