진공주조법에 의한 TiNi 형상기억합금 강화 6061Al 지적 복합재료의 계면 및 인장 특성

박광훈,박성기,신순기,박영철,이규창,이준희,Park, Gwang-Hun,Park, Seong-Gi,Sin, Sun-Gi,Park, Yeong-Cheol,Lee, Gyu-Chang,Lee, Jun-Hui 한국재료학회 2001 한국재료학회지 Vol.11 No.12

We investigated the change of mechanical properties for TiNi shape memory alloy by heat treatment. 6061Al matrix composites with TiNi shape memory alloy as reinforcement were fabricated by vacuum casting. TiNi alloy has the maximum tensile strength at 673K treated and there is no change of tensile strength and hardness at 448K treated. The composites, prepared by vacuum casting, showed good interface bonding by vacuum casting. It was about 3$\mu\textrm{m}$ of thickness of the diffusion layer. Tensile strength of the composite was in higher than that of 6061Al alloy as increased value of about 70MPa at room temperature and about 110MPa at 363K. We thought that the increase of the tensile strength at 363K was due to reverse transformation of the TiNi shape memory alloy.

진공 Hot Press법에 의한 TiNi/6061Al 지적 복합재료의 확산층 형성거동

박광훈,박성기,신순기,이준희,Park, Kwang-Hoon,Park, Sung-Ki,Shin, Soon-Gi,Lee, Jun-Hee 한국재료학회 2002 한국재료학회지 Vol.12 No.12

2.7vol%TiNi/6061 Al composites with TiNi shape memory alloy as reinforcement were fabricated by vacuum hot press. It was investigated by OM, SEM, EPMA and XRD analysis for the behavior of diffusion layer formation on various heat treatment condition. Thickness of diffusion layer was increased proportionally according to heat treatment time. The layer was formed by the mutual diffusion of TiNi and Al. The diffusion rate from TiNi fiber to Al matrix was faster than that of reverse diffusion path. The more diffused layer was formed in Al matrix. The diffusion at interface layer was consisted of $A1_3$Ti, $Al_3$Ni analyzed by EPMA, XRD results.

MPEG에 대하여

박광훈,Park Gwang-Hun 한국공학교육학회 1997 Ingenium(人材니움) Vol.4 No.1

폐과오종(肺過誤腫)의 일치험례(一治驗例)

박광훈,지정희,Park, Gwang-Hun,Ji, Jeong-Hui 대한흉부심장혈관외과학회 1976 Journal of Chest Surgery (J Chest Surg) Vol.9 No.2

Since. its first description by Albrecht in 1904 that hamartoma (Greek. meaning "error" and "tumor")is tumor-like malformation characterized by abnormal mixture of normal constituent in any organ it arises, hamartoma involving the lung has assumed the following clinical features.: 1) all the pulmonary lesions presenting as "coin lesions", it occupies about 8% according to various reports. It also constitutes the most prevalent lesion of all the benign lung tumors, appearing in 0.25% of the general population. 2) Peak incidence of the lesion occurs in the 5th and 6th decade as the carcinoma patient do, and the occasional growing tendency and periperal location as in this presentation renders the differential diagnosis from the malignant disease difficult and surgical intervention inevitable for definite histological diagnosis and treatment. 3) Nearly all the clinical investigations such as history, physical exam, bronchoscopy, culture, and cytological exam of sputum sre likely to futile:the only tool for detecting the presence of the lesion is X-ray, butthat's short of telling the true nature of it. 4) Because of its age of presentation and growing tendency in middle-aged adult, it still controversial whether it is developmental anomaly as Albrecht described, or true neoplasm denovo of fibrous connective tissue origin. This is a case report of surgical experience of pulmonary hamartoma which had nearly all the typical clinical features above mentioned and was reviewed with related literatures.

SOFM 신경망 분류기를 이용한 MPEG-4 비디오 전송률 제어

박광훈,이윤진,Park, Gwang-Hoon,Lee, Yoon-Jin 한국정보과학회 2002 정보과학회논문지 : 소프트웨어 및 응용 Vol.29 No.7

This paper introduces a macroblock-based rate control algorithm using the neural classifier based in Self Organization feature Maps (SOFM). In contrast to the conventional rate control methods based on the mathematical rate distortion (RD) model and the feedback regression, proposed method can actively adapt to the rapid-varying image characteristics by establishing the global model for bitrate control and by using the SOFM based neural classifier to manage that model. Proposed rate control algorithm has 0.2 dB ~ 0.6 dB better performances than MPEG-4 macroblock-based rate control algorithm by evaluating with the encoded Peak Signal to Noise Ratios while maintaining similar overall computational complexity. 본 논문에서는 SOFM기반 신경망 분류기를 이용한 매크로블록 기반 전송률제어 방식을 제안한다. 수학적 왜곡 비트율 모델과 귀환회기 방식을 기반으로 하는 기존의 전송률 제어 방법에 비하여, 제안된 방법은 전송비트 제어용 전역모델을 설정하고 이를 최적으로 제어할 수 있는 SOFM기반 신경망 분류기를 이용하여 영상특성 변화에 적극적인 대처를 할 수 있다. 제안된 전송률 제어 알고리즘은 기존의 MPEG-4 매크로블록 기반 전송률 제어 알고리즘에 비해 전체 연산 복잡도는 비슷하게 유지하면서 피크신호 대 잡음비의 비교에 있어서 0.2 dB ~ 0.6 dB 정도 성능이 우수함을 확인하였다.

함께하는 삶 II - 민간 의료기관 RNA 정량검사 시행에 대한 어느 감염인의 소리

박광훈,Park, Gwang-Hun 대한에이즈예방협회 2009 레드리본 Vol.83 No.-

RNA 정량검사는 혈중 바이러스 농도를 측정하는 검사로, 감염인의 투약과 치료에 필수적인 검사로써 감염인이라면 $3{\sim}6$개월 간격으로 정기적으로 받는 검사이다. 그동안 국가에서 시행해 왔던 RNA 정량검사가 2009년 7월 1일자로 민간 의료기관에서 시행된다. RNA 정량검사를 민간 의료기관에서 실시하게 됨에 따라 감염인의 진료비 부담이 증가하게 된다. 병원에 따라서는 감염인의 비급여 본인부담금을 고려하여 특진료를 가산하지 않는 병원도 있으나 이는 극히 일부 병원에 불과한 실정이다.

AC방식 PHC Pile의 분체조성에 따른 양생 단계별 압축강도 특성 평가

박광훈(Park, Kwang Hoon),백승재(Baek, Seung Jae),송용순(Song, Yong Soon),허홍기(Hur, Hong Ki) 한국콘크리트학회 2016 한국콘크리트학회 학술대회 논문집 Vol.28 No.2

H.264 기반 선택적인 미세입자 스케일러블 코딩 방법

박광훈(Gwang Hoon Park),유원혁(Won Hyuck Yoo),김규헌(Kyuheon Kim) 한국정보과학회 2004 정보과학회 컴퓨팅의 실제 논문지 Vol.10 No.4

본 논문에서는 선택적으로 강화계층의 시간적 예측 정보를 사용하는 H.264 기반 선택적인 미세입자 스케일러블 비디오 코딩 방법을 제안한다. 제안된 방법의 기본계층은 최근 표준화되었으며 고압축률이 특징인 H.264 (MPEG-4 Part 10 AVC) 알고리즘으로 코딩한다. 강화계층은 기본적으로 국제표준인 비트플레인 기반 MPEG-4 (Part 2) 미세입자스케일러블 코딩 방법으로 코딩한다. 본논문에서는 엔코더측에서 강화계층간 시간적 예측 방법에 의해 발생된 효과적인 영상 정보를 드리프트 현상이 최소화 하는 방향으로 선택적으로 적용하여 디코더측에 전송하는 방안을 제안하였다. 강화계층간 예측 방법만을 추가했을 때는 시간적 중복성을 줄여주는 효과를 볼 수 있지만 저비트율 대역에서 엔코더와 디코더간의 참조 저장영상 불 일치로 인한 드리프트 현상이 심하게 발생한다. 제안된 알고리즘은 시간적 예측 결과가 우수하여 코딩효율을 현저히 높혀줄 수 있는 경우에만 선택적으로 강화계층간의 시간적 예측 정보를 사용하였으며, 이로 인하여 저비트율 대역에서의 드리프트 현상을 현저하게 줄일수 있었으며, 전반적으로 코딩 효율을 높여주는 효과를 가져왔다. 여러 영상 시퀀스를 대상으로 실험한 결과, 제안된 코딩 방법은 현존하는 국제표준인 MPEG-4 기반 미세입자 스케일러블 코딩 방법보다 같은 비트율 대역에서 영상화질이 약 3~5 dB 높은 성능을 보여주고 있으며, H.264를 기반으로한 미세입자 스케일러블 코딩 방법보다도 약 1~3 dB 높은 성능을 보여주고 있음을 발견할 수 있었다. This paper proposes the H.264-based selective fine granular scalable (FGS) coding scheme that selectively uses the temporal prediction data in the enhancement layer. The base layer of the proposed scheme is basically coded by the H.264 (MPEG-4 Part 10 AVC) visual coding scheme that is the state-of-art in codig efficiency. The enhancement layer is basically coded by the same bitplane-based algorithm of the MPEG-4 (Part 2) fine granular scalable coding scheme. In this paper, we introduce a new algorithm that uses the temproal prediction mechanism inside the enhancement layer and the effective selection mechanism to decide whether the temporally-predicted data would be sent to the decoder or not. Whenever applying the temporal prediction inside the enhancement layer, the temporal redundancies may be effectively reduced, however the drift problem would be severly occurred especially at the low bitrate transmission, due to the mismatch bewteen the encoder’s and decoder’s reference frame images. Proposed algorithm selectively uses the temporal-prediction data inside the enhancement layer only in case those data could siginificantly reduce the temporal redundancies, to minimize the drift error and thus to improve the overall coding efficiency. Simulation results, based on several test image sequences, show that the proposed scheme has 1~3 dB higher coding efficiency than the H.264-based FGS coding scheme, even 3~5 dB higher coding efficiency than the MPEG-4 FGS international standard.

2차원 히스토리 풀과 슬라이딩 윈도우를 이용한 MPEG - 4 비디오 프레임 기반 비트 생성율 제어 방법

박광훈(Gwang Hoon Park),이윤진(Yoon Jin Lee) 한국정보과학회 2002 정보과학회논문지 : 소프트웨어 및 응용 Vol.29 No.5·6

본 논문에서는 2차원 히스토리 풀과 슬라이딩 윈도우를 이용한 MPEG-4 비디오 프레임 기반 비트 생성율 제어 방법을 제안한다. 제안된 방법은 먼저 영상 특성에 따라 코딩 결과를 분류하여 2차원 히스토리 풀에 저장한다. 슬라이딩 윈도우를 이용하여 코딩하려는 영상 프레임의 특성과 비슷한 특성을 갖는 코딩 결과들을 풀에 저장된 결과로부터 수집한다. 마지막으로 수집된 코딩 결과를 이용하여 귀환회귀를 수행하는 방법이다. 제안된 방법을 이용하면 양자화 스텝 결정 시 외삽이 발생되는 경우를 줄여줌으로써 급변하는 영상 특성 변화에 적극적으로 대처할 수 있다. 제안된 비트 생성율 제어 방법은 기존의 MPEG-4 프레임 기반 비트 생성율 제어 방법에 비해 전송선로의 제약을 만족하는 프레임 당 발생된 비트량, 피크 신호 대 잡음비 그리고 프레임 스킵 수의 비교에 있어서 성능이 우수함을 확인하였다. This paper introduces the MPEG-4 video frame-based bitrate control methodology using two dimensional history pool and a sliding window. Proposed method preferentially clusters the encoded results according to the image characteristics and stores those results into the 2 dimensional history pool. Among the stored results in the pool, the sliding window collects the encoded results whose characteristics are very similar to the image frame to be encoded. Feedback regression is finally carried out based on the collected results. Therefore proposed method can actively adapt to the rapid varying image characteristics by reducing the occurrences of the extrapolations when determining the quantization steps. Proposed method has better performances than the MPEG-4 frame-based bitrate control algorithm by evaluating with the actually encoded bits per frame, encoded PSNR’s, and frame skips.

메를로 퐁티의 현상학을 통한 신체에 대한 해석

박광훈(Park, Kwang-Hun) 한국체육철학회 1998 움직임의철학 : 한국체육철학회지 Vol.6 No.2

This study was to interpret the concept of body by applying existential phenomenology of Merleau Ponty, which involves significant philosophical issues on the discourse of contemporary physical education. The reason why this study dealt with Ponty`s perspective on the body is related that he manifested to bolster monistic approach between mind and body. Throughout whole philosophical discourse, Ponty`s approach made it possible to emerge the body as subject and active reality, rather than to consider it as passive thing, separated from mind. In this basic respect, this study aimed to interpret the concept of body to insightfully understand its relation with other things such as life-world, consciousness, meaning, and so on. According to this study, main ideas of Ponty`s phenomenology were divided into three directions. The first, the existence by body is major concept in Ponty`s phenomenology. The second, in terms of methodological consideration, Ponty tried to interpret the phenomenon on the state of being pre-consciousness, as it is. The third, the body Ponty conceived is an active body which body itself could feel something. In order to justify these directions, Ponty suggested two philosophical terms of body, called as subject-body, and perception-subject body, in his book titled in Phenomenology of perception. As subject-body and perception-subject body, the discourse of body played a great role to realize the reality of body, not only as an intentional subject, but also as a meaning-giver. The concept of body suggested by Ponty may lead to develop various changes of physical education. There are three considerations. Firstly, it may suggest that a lived experience is considered as a significant topic in the realm of physical education. Secondly, the field of physical education must pursue to construct the phenomenological description for meaning and experience for bodily movement. At last, in terms of academic attitude, the educational trend of physical education based on phenomenology may intend to put much value on qualitative aspect on whole educational processes. Ponty`s idea already has been introduced to various realms related to human science. Now we, physical educators, have to rethink the lived-body of Ponty to build our insight goal and objective on physical education. That might be beyond the academic pursuit. It makes to understand human being and our movements thoughtfully.