D.G.S.선도(線圖)의 이용방법(李用方法) (II)

박은수,Park, U.S. 한국비파괴검사학회 1985 한국비파괴검사학회지 Vol.5 No.1

족압검사를 이용한 만성 발목 불안정성과 압력중심의 연관성

박은수,서상교,이호승,Park, Eun Soo,Seo, Sang Gyo,Lee, Ho Seong 대한족부족관절학회 2020 대한족부족관절학회지 Vol.24 No.1

Purpose: Chronic ankle instability is a very common abnormality of the ankle, but there is still controversy regarding its evaluation criteria. The stress view has difficulties in reflecting the patient's symptoms and treatment progress. Therefore, this study examined the relationship between the center of pressure (COP) measured by a pedobarograph and the symptoms of the patient. Materials and Methods: Thirty patients with chronic ankle instability from February to August 2018 were included. Each patient was surveyed with the foot and ankle outcome score (FAOS). The COP was measured with a foot pressure scanner, and the travel distance and ellipse area of the COP were calculated. Each patient was measured on one foot and on two feet with his or her eyes closed and open. The relationship between the COP measurement and FAOS score was analyzed using the Pearson correlation coefficient. Results: The participants were consisted of 21 male and nine female, with a mean age of 30 years, mean weight of 72 kg, and mean foot size of 259 mm. With the eyes open, the correlation coefficient between the FAOS and travel distance of the affected side was -0.394 (p<0.05) and that between the FAOS and the ellipse area of the affected side was -0.425 (p<0.05). On the other hand, no significant correlations were found between the travel distance and ellipse area of the affected side when patients closed their eyes. Conclusion: Measurement of the COP using foot pressure scanner could evaluate objectively patients with chronic ankle instability, with measurements in patients with their eyes open being more significant. Based on the findings of this study, an analysis of the COP with the patients with their eyes open and standing on one foot may help determine the management strategy and assess the progress of the patients.

SCM440 강의 결정입도와 조직의 변화에 따른 초음파 감쇄

박은수,강계명,김선진,장순식,Park, Eun-Su,Gang, Gye-Myeong,Kim, Seon-Jin,Jang, Sun-Sik 한국재료학회 1993 한국재료학회지 Vol.3 No.6

여러 온도에서 급냉 및 템퍼링시킨 SCM440강을 이용하여 결정입도와 조직의 변화가 초음파감쇄에 미치는 영향에 관하여 연구하였다. 초음파감쇄는 주로 결정립에 의한 산란에 기인하였으며 감쇄계수는 결정립의 크기가 클수록 증가하였으나 템퍼링 시킨 조직의 경우 템퍼링온도가 높아질수록 감쇄계수는 감소하는 것을 알 수 있었다. 주파수의 의존성은 직선적인 log-log 관계를 가지며 Roney의 식과 비례하는 것으로 조사되었다. The effects of grain size and microstructure on the ultrasonic attenuation was investigated with SCM440 steel quenched and tempered at various temperatures. The ultrasonic attenuation was primarily due to the grain boundary scattering and the ultrasonic attenuation coeffecient increased with increasing grain size. In the meantime, it was found that the ultrasonic attenuation coefficient decreased with increasing tempering temperature. The dependence of ultrasonic attenuation coefficient on the frequency of ultrasonic wave had linear relationship on a log-log scale and was proportional to the Roney's equation.

원자력발전소 PSI/ISI 데이더 관리를 위한 지능형 데이더베이스 프로그램 개발 (제 2보)

박은수,박익근,엄병국,이종포,한치현,Park, Un-Su,Park, Ik-Keun,Um, Byong-Guk,Lee, Jong-Po,Han, Chi-Hyun 한국비파괴검사학회 2000 한국비파괴검사학회지 Vol.20 No.3

제 1보에서 Windows 환경 하에서 PSI/ISI 데이터의 효율적 관리 및 다원적평가와 분석이 가능한 고리 원전 PSI/ISI 데이터베이스 구축과 프로그램 개발(IDPIN)에 대해 소개하였다. 제 2보에서는 월성 원자력발전소 PSI/ISI 자료 관리를 위한 지능형 데이터베이스 프로그램(WS-IDPIN)을 개발하였다. 이 프로그램에는 월성 원전 PSI/ISI 관련 자료 분석 기능, PSI/ISI UT 검사 보고서 양식의 표준화와 전산 시스템화, PSI/ISI 비파괴검사 결과의 통계적 신뢰도 평가 프로그램(depth and length sizing performance 등) 등을 개발하여 원전 PSI/ISI 데이터 관리 전문가시스템(expert system)화에 한 단계 접근하였다. In a previous paper, we have discussed the intelligent Windows 95-based data management program(IDPIN) which was developed for effective and efficient management of large amounts of pre-/in-service inspection(PSI/ISI) data of Kori nuclear power plants. The IDPIN program enables the prompt extraction of previously conducted PSI/ISI conditions and results so that the time-consuming data management, painstaking data processing and analysis of the past are avoided. In this study, the intelligent Windows based data management program(WS-IDPIN) has been developed as an effective data management of PSI/ISI data for the Wolsong nuclear power plants. The WS-IDPIN program includes the modules of comprehensive management and analysis of PSI/ISI results, statistical reliability assessment program of PSI/ISI results(depth and length sizing performance etc), standardization of UT report form and computerization of UT results. In addition, the program can be further developed as a unique PSI/ISI data management expert system which can be part of the PSI/ISI total support system for Korean nuclear power plants.

SCM440, SCM415강의 표면강화에 따른 초음파의 전파특성

박은수,강계명,김선진,장순식,Park, Eun-Su,Gang, Gye-Myeong,Kim, Seon-Jin,Jang, Sun-Sik 한국재료학회 1993 한국재료학회지 Vol.3 No.5

초음파의 표면파의 전파특성을 이용하여 SCM440강의 고주파열처리의 정도에 따른 표면경화층의 깊이를 측정, 조사하였으며 침탄속도는 동일조직에서는 주파수에 관계없이 일정하였으나, 경화조직에서 경화되지 않은 조직에 비하여 표면파의 속도는 59m/s 늦었다. 강의 유효경화층깊이(d)와 표면파파장($\lambda_{R}$)의 d/$\lambda_{R}$의 관계로부터 경화층의 \ulcorner이를 비파괴적으로 평가, 측정할 수 있었으며 침탄경화시킨 경우에서도 동일한 결과를 얻었다. By using propagation characteristics of ultrasonic surface wave, the depth of the surface hardened layer of SCM440 steel with different high frequency induction heat treatments was measured and the same was done on the carburized SCM415 steel. The propagation velocity of surface wave was constant and independent of frequency in t.he specimens with identical microstructure, it was, however, decreased by 59m/s in the hardened layers compared to the unhardened part. From t.he relationship between the effective case depth and the wave length of surface wave, the depth of the hardened layer could be measured and evaluated nondestructively for both induction hardened and carburized steels.

고강도 고인성 마그네슘 합금 개발동향

박은수,김재우,김도향 ( Eun Soo Park,Jae Woo Kim,Do Hyang Kim ) 한국주조공학회 1998 한국주조공학회지 Vol.18 No.2

Mg-Zn-Y 합금에서 준결정 및 준결정 유사상

박은수,옥재범,김원태,김도향,Park, Eun-Soo,Ok, Jae-Bum,Kim, Won-Tae,Kim, Do-Hyang 한국현미경학회 2002 Applied microscopy Vol.32 No.1

As-cast microstructure of Mg-rich $Mg_{68}Zn_{28}Y_4$ has been investigated by a detailed transmission electron microscopy. The as-cast $Mg_{68}Zn_{28}Y_4$ alloy consisted of three different types of phases: $10{\sim}20{\mu}m$ size primary solidification phase, dendritic phase grown from the primary phase and a eutectic structure formed at the later stage of solidification. The primary solidification phase has an icosahedral structure with a large degree of phason strain. 1/1 rhombohedral approximant phase with lattice parameters: $a=27.2{\AA}\;and\;{\alpha}=63.43^{\circ}$ is first observed in Mg-Zn-Y system. The rhombohedral structure can be obtained by introducing phason strain in the six dimensional face centered hyper-cubic lattice. The decagonal phase nucleates with orientation relationship with the icosahedral phase, and $Mg_4Zn_7$ nucleates with orientation relationship with the decagonal phase, indicating a close structural similarity between the three phases. Gradual depletion of Y during solidification plays an important role in heterogeneous nucleation of decagonal and $Mg_4Zn_7$ phases from icosahedral and decagonal phases respectively. [ $Mg_{68}Zn_{28}Y_4$ ] 합금의 응고 조직은 primary solidification phase, primary solidification phase로부터 성장된 ${\alpha}-Mg$ dendrite, 그리고 응고 말기에 형성된 eutectic structure의 세 가지형태 조직으로 구성되어져 있다. Primary solidification phase에는 매우 큰 정도의 phason strain이 존재하고 있으며, $a=27.2{\AA}\;and\;{\alpha}=63.43^{\circ}$의 격자상수를 갖는 1/1 rhombohedral approximant가 존재한다. 이와 같은 rhombohedral approximant의 구조는 six dimensional face centered hyper-cubic lattice에 phason strain을 도입함에 의해 얻어질 수 있다. Decagonal phase는 icosahedral phase로부터 방위 관계를 가지며 형성되며, $Mg_4Zn_7$는 decagonal phase로부터 방위관계를 가지며 성장한다. 이는 세 상간에 구조적 유사성이 존재하고 있음을 의미하며, 응고시 용질원자의 분배에 의해 이들 세 상이 순서대로 형성되어진다.

금속 비정질 재료의 기초 및 응용 시리즈 II

박은수,Park, Eun-Soo 한국주조공학회 2009 한국주조공학회지 Vol.29 No.4

그림자 제거와 색도 히스토그램 비교를 이용한 배회행위 검출

박은수,이형호,윤명규,김민규,곽종훈,김학일,Park, Eun-Soo,Lee, Hyung-Ho,Yun, Myoung-Kyu,Kim, Min-Gyu,Kwak, Jong-Hoon,Kim, Hak-Il 한국정보보호학회 2011 정보보호학회논문지 Vol.21 No.6

본 논문에서는 감시영역을 벗어난 후 다시 돌아온 객체에 대한 배회행위를 효과적으로 인식 할 수 있는 지능형 배회행위 검출 시스템을 제안한다. 전경과 배경을 가우시안 혼합 모델을 이용하여 분리하고 그림자를 제거하여 객체를 인식한 후, 객체의 색도 히스토그램을 이용하여 감시영역을 벗어난 후 돌아온 객체들을 판단하고 감시영역에 존재하는 시간을 보전한다. 배회행위를 판단하기 위해 카메라 캘리브레이션을 통해 실세계 배회패턴과 같은 행태의 매크로 블록을 영상좌표에 도입한 후 배회궤적을 추출하고, 감시영역에 객체가 존재하는 시간을 함께 고려하여 배회행위를 판단한다. 제안하는 방법은 실험에 사용된 모든 배회행위 프레임에서 정확하게 배회행위를 검출하여 그 효과를 입증하였다. Proposed in this paper is the intelligent video surveillance system to effectively detect multiple loitering objects even that disappear from the out of camera's field of view and later return to a target zone. After the background and foreground are segmented using Gaussian mixture model and shadows are removed, the objects returning to the target zone is recognized using the chromaticity histogram and the duration of loitering is preserved. For more accurate measurement of the loitering behavior, the camera calibration is also applied to map the image plane to the real-world ground. Hence, the loitering behavior can be detected by considering the time duration of the object's existence in the real-world space. The experiment was performed using loitering video and all of the loitering behaviors are accurately detected.

신재료의 비파괴평가기술 현황과 과제

박은수,강계명,Park, Eun-Su,Gang, Gye-Myeong 재료연구소 1993 機械와 材料 Vol.5 No.4