• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2000년도 ITC-CSCC -2
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• pp.637-640
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• 2000

ERG signal represents the responses of the each layer of retina for the visual stimulus and accumulated responses according to the signal processing occurring in the retina. By investigating the reaction types of each wave of the ERG, various kinds of information for the diagnosis and the signal processing mechanisms in the retina can be obtained. In this paper, the ERG signal is generated by simulating of the volume conductor field of response of each retina layer and summing of them algebraically. The retina model used for simulation is Shah’s Computer Retina model which is one of the most reliable models recently developed. The generated ERG is compared with the typical ERG and shows a very close similarity. By changing the parameters of the retina model, the diagnostic investigation is performed with the variation of the ERG waveform.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2004년도 추계학술대회 논문집 전기물성,응용부문
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• pp.251-254
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• 2004

The aging diagnosis technique using partial discharge detection method detects partial discharge signals cause of power equipment failuer and able to forecast the aging state of insulation system through analysis algorithm, in this paper accumulates HFPD signal during constant scheduled cycles to build HFPD pattern and then analyzes HFPD pattern using statistical parameters and ${\Delta}F$ pattern. The 3D pattern is composed of detected signal frequency, amplitude and repeated number and the FRPDA(frequency resolved partial discharge analysis) technique is used in 3D pattern construction. The ${\Delta}F$ pattern shows variation characteristics of amplitude gradient of consecutive HFPD signal Pulses and able to classify discharge types-internal discharge, surface discharge and coronal discharge etc. Fractal mathematics applied to ${\Delta}F$ pattern quantification and neural networks is used in aging diagnostic algorithm.

• 한국음향학회지
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• 제27권6호
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• pp.263-270
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• 2008

초음파 어레이 센서의 성능은 구성 불성과 많은 구소 변수들에 의해 결정된다. 본 연구에서는 유한 요소해석을 통하여 구조적인 변화에 따른 초음파 어레이 센서의 성능변화를 해석하였다. 해석 결과를 기초로 하여 초음파 어레이 센서가 주파수 대역폭, 중심 주파수 그리고 -20 dB pulse length와 같은 요구 사항을 모두 만족시키며 최대의 감도를 가지도록 구조를 최적화하였다. 최적화 방법으로는 초음파 어레이 센서의 성능을 목적 함수로 하는 SQP-PD 방법을 사용하였다. 최적화된 초음파 어레이 센서는 의료 영상 진단에 적용되기 위한 모든 요구 조건을 만족하였으며, 본 설계 기술은 유사한 형태의 다른 배열형 초음파 센서에 응용 가능하다

• 대한방사선기술학회지:방사선기술과학
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• 제46권1호
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• pp.1-8
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• 2023

As the demand for bone mineral density testing increases in Korea, which is close to an aging society, it is necessary to evaluate the repeatability of equipment such as femur phantom other than l-spine for more accurate diagnosis. However, in clinical practice, it is often not possible to proceed such evaluation due to insufficient quality control conditions. Therefore, this study is to evaluate the usefulness of the femur phantom after fabricating the same using 3D printing technology. The femur phantom was output using GlowFill filament and FDM 3D printing type. Each phantom was repeatedly scaned 20 times to compare whether the existing l-spine phantom and the fabricated femur phantom were suitable as a phantom for quality control. Each time the seven researchers took three times, the location of the femur phantom was readjusted, and then scanned to confirm the error between the researchers. As a result of conducting repeatability evaluation using femur phantom, the coefficient of variation rate was 2%, which was within the minimum precision tolerance of 2.5%. The reproducibility between the researcher was also found to be suitable as the average coefficient of variation was 0.031 and the coefficient of variation rate was 3.1%, which was within the minimum precision error range of 5%. In conclusion, it is considered that the prospective attitude and usefulness of the femur phantom fabricated by 3D printing in clinical practice will be sufficient.

• 대한한방부인과학회지
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• 제26권4호
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• pp.140-149
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• 2013

Purpose: The purpose of this study is to investigate the change and correlation of pulse energy in Left and Right Chon, Kwan, Cheok during menstruation, especially around menstruation start date. Methods: The subjects of this experiment were 8 healthy women whose menstruation periods are regular. We measured 3D Blood Pressure Pulse Analyzer (3D-MAC) tests before and after menstruation start date. Results: The results were as follows 1. The pulse energy of the Right Chon was significantly decreased and Left Kwan was comparatively increased during the next day of menstruation start date than previous day. 2. There was a negative correlation between Left Kwan and Left Cheok, Right Chon and Right Kwan pulse energy during the previous and menstruation start date. The negative correlation disappeared between Right Chon and Right Kwan at the next day of menstruation start date. Conclusions: The results suggest that Chon, Kwan, Cheok pulse energy changes are related to menstruation and reflect physiological mechanism of menstruating women. Further study will be needed.

• 한국지능시스템학회논문지
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• 제18권5호
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• pp.659-665
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• 2008

전립선 비대증은 고령 남성의 대표적 만성질환으로서 간단하면서도 비침습적인 방법인 요류검사를 수행하여 진단한다. 이러한 전립선 비대증을 진단하기 위한 제품들이 사용되고 있으나, 기존 제품은 특징되는 파라미터의 결과만 제공할 뿐 시간에 따른 오류의 변화, 데이터베이스 기능 등 환자의 정보를 제공하지 못하는 단점이 있다. 이에 본 논문에서는 유비쿼터스환경을 고려한 무선모듈과 LabVIEW 기반의 윈도우 프로그램을 이용하여 전립선 진단을 위한 특징 파라미터 추출 프로그램의 개발뿐만 아니라 환자 정보의 데이터베이스가 가능한 시스템을 개발하였다.

• 대한예방한의학회지
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• 제13권1호
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• pp.105-115
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• 2009

Background: The resource-based relative value scale has been applied to Korean medicine services as part of the National Health Insurance, yet the proper scoring method for physician's work needs to be developed. Objectives: To measure physician's work for Korean medicine services using Analytical Hierarchy Process(AHP) and to compare results abstracted by AHP with those by Magnitude Estimation method. Methods: We developed the AHP questionnaires for Korean Medicine services and administered it to 12 Korean medicine insurance experts. Weighted scores were calculated and were converted into physician's work scores. Results: In AHP measurement, the physician's work scores for acupuncture activities, especially special acupunctures, far increased, while those for diagnosis and basic consultations decreased. Variations in the scores enlarged. Conclusions: As an alternative, AHP method can be considered for measuring the physician's work for Korean medicine services with careful management of scoring variation.

• 한국철도학회논문집
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• 제12권5호
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• pp.725-731
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• 2009

강 교량, 선로 구조물, 차량 구조물 등 철도분야에서 강 재료가 많이 사용되고 있다. 설계, 강도평가, 잔존수명 평가 등을 위하여 부식된 강 재료에 대한 인장강도, 피로강도 등이 필요하지만 우리나라의 경우 이 분야의 연구가 미진하여 축적된 데이터가 많지 않다. 본 연구에서는 철도 분야에서 많이 사용되는 대표적인 강 재료에 속하는 SM490A와 SS400에 대해 대기부식 시험절차를 확립하고 많은 시편을 대기부식에 노출시켜 일정한 시간 간격으로 수거하여 인장 및 피로시험을 수행하여 부식시간의 경과에 따른 인장 및 피로강도의 변화를 측정하였다. 처음 3-4개월 기간에 피로강도가 많이 저하하였고 그 이후에는 완만히 변화하였다. 그리고 후열처리 한 시편이 부식에 대한 저항이 더 크다는 것도 알 수 있었다.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2006년도 하계학술대회 논문집 Vol.7
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• pp.515-516
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• 2006

The resistive leakage current is an important parameter for arrester diagnosis. However, the 3rd harmonic leakage current is more widely used than the resistive one because of its easy measurement. In this paper, we studied the correlation between the resistive and the $3^{rd}$ harmonic leakage current of ZnO arresters. The resistive leakage current was measured according to the IEC 60099-5 in AC applied voltage. The $3^{rd}$ harmonic leakage current was analyzed by using a designed band-pass filter having 180 [Hz]-center frequency and 10 [Hz]-bandwidth. The experimental results show that the $3^{rd}$ harmonic leakage current changes proportionally with the resistive leakage current variation under the maximum continuous operating voltage (MCOV).

• 대한유전성대사질환학회지
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• 제22권1호
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• pp.15-20
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• 2022

The most common urea cycle disorder is ornithine transcarbamylase deficiency. More than 80 percent of patients with symptomatic ornithine transcarbamylase deficiency are late-onset, which can present various phenotypes from infancy to adulthood. With no regards to the severity of the disease, characteristic fluctuating courses due to hyperammonemia may develop unexpectedly, and can be precipitated by various metabolic stressors. Late-onset ornithine transcarbamylase deficiency is not merely related to a type of genetic variation, but also to the complex relationship between genetic and environmental factors that result in hyperammonemia; therefore, it is difficult to predict the prevalence of neurological symptoms in late-onset ornithine transcarbamylase deficiency. Most common acute neurological manifestations include psychological changes, seizures, cerebral edema, and death; subacute neurological manifestations include developmental delays, learning disabilities, intellectual disabilities, attention-deficit/hyperactivity disorder, executive function deficits, and emotional and behavioral problems. This review aims to increase awareness of late-onset ornithine transcarbamylase deficiency, allowing for an efficient use of biochemical and genetic tests available for diagnosis, ultimately leading to earlier treatment of patients.