MPEG-2 비디오 부호화를 위한 정확한 비트율 제어 알고리즘

이정우,호요성,Lee, Jeong-U,Ho, Yo-Seong 대한전자공학회 2001 電子工學會論文誌-SP (Signal processing) Vol.43 No.2

The MPEG-2 Test Model 5 (TM5) algorithm is widely used for bit rate control. In TM5, however, the target number of bits and the number of actual coding bits for each picture do not match well. Therefore, buffer overflow and picture quality degradation may occur at the end of the GOP. In this paper, we propose a new bit rate control algorithm for matching the target and the actual coding bits based on accurate bit allocation. The key idea of the proposed algorithm is to determine quantization Parameters which enable us to generate the number of actual coding bits close to the target number of bits for each picture, while maintaining uniform picture quality and supporting real-time processing. The proposed algorithm exploits the relationship between the number of actual coding bits and the number of estimated bits of the previous macroblock. MPEG-2 비디오 부호화 과정에서 비트율 제어를 위해 MPEG-2 Test Model 5 (TM5) 알고리즘이 널리 사용되고 있지만, 실제로는 각 화면에 할당되는 목표 비트수와 실제 부호화된 비트수가 잘 맞지 않아 한 GOP의 마지막 부분에서 버퍼 넘침 현상과 화질의 급격한 열화 현상이 발생할 수 있다. 본 논문에서는 부호화하고자 하는 블록의 이전 블록에서 실제 발생된 비트수와 예측에 의한 비트수 사이의 관계를 이용하여 정확한 비트수를 할당함으로써, 각 화면의 목표 비트수와 실제 발생되는 부호화 비트수를 정합시키는 새로운 비트율 제어 알고리즘을 제안한다. 제안된 알고리즘은 화면내에서 일관된 화질을 유지하며, 실시간 처리도 가능하다.

전기생리학적 기전에 근거한 망막 모델의 제안과 시공간적 응답의 분석

이정우,채승표,조진호,김명남,Lee, Jeong-Woo,Chae, Seung-Pyo,Cho, Jin-Ho,Kim, Myoung-Nam 대한전자공학회 2002 電子工學會論文誌-SC (System and control) Vol.39 No.6

본 논문에서는 망막의 전기생리학적 기전을 바탕으로 실제 망막과 유사한 기능 및 응답 특성을 갖는 망막 모델을 제안하였다. 시세포에서 양극세포까지는 기존에 연구된 여러 망막 모델들을 종합하여 모델링하였고, 3 NDP 기전을 이용하여 움직임 정보를 검출한다고 알려져 있는 아마크린세포와 양극세포 터미널에 관한 새로운 모델을 제안하였다. 이 모델의 평가를 위하여, 공간상의 동적 자극과 정지 자극에 대한 응답 특성을 비교 분석을 하였을 뿐만 아니라 자극의 움직임 속도에 따른 특성에 대한 분석도 수행하여 제안한 망막 모델을 검증하였다. 본 연구결과는 움직임 정보를 검출하기 위한 비전 시스템에 대한 인간 시각 시스템의 적용 및 생체에 이식할 수 있는 인공 망막의 개발을 위한 기초 연구에 이용될 수 있을 것이다. Based on electrophysiological retina mechanism, a retina model is proposed, which has similar response characteristics compared with the real primate retina. Photoreceptors, horizontal cells, and bipolar cells are modeled based on the previously studied retina models. And amacrine cells known to have relation to movements detection, and bipolar cell terminals are newly modeled using 3 NDP mechanism. The proposed model verified by analyzing the spatial response characteristics to stationary and moving stimuli, and characteristics for different speeds. Through this retina model, human vision system could be applied to computer vision systems for movement detection, and it could be the basic research for the implantable artificial retina.

과다 유두(Supernumerary Nipple) 2례

이정우,양정덕,이정훈,최강영,김귀락,정호윤,조병채,Lee, Jeong-Woo,Yang, Jung-Dug,Lee, Jung-Hun,Choi, Kang-Young,Kim, Gui-Rak,Chung, Ho-Yun,Cho, Byung-Chae 대한성형외과학회 2010 Archives of Plastic Surgery Vol.37 No.5

Purpose: Supernumerary nipple or polythelia is one of the developmental anomalies occurring at the embryonic stage and this anomaly usually arises from the milk line. While this atypical feature is determined during early developmental stage, it may not come out obviously or become troublesome until puberty or lactation. Moreover, sometimes it is confused with a pigmented nevus. Methods: Case 1, a 18-year-old woman with intramammary supernumerary breast consisted of another nipple with middle sized areola on the right lower breast was admitted for a $2.8{\times}3.1\;cm$-sized mass on the right breast which was starting appeared 1 year earlier. The preliminary cytological examination of the material obtained by needle aspiration biopsy from the mass was revealed by fibroadenoma with no malignant change. The patient had the surgical excision of the mass and accessory breast. Case 2, a 16 year-old woman admitted for intra-areolar polythelia of the left breast, even she doesn't have any family history of polythelia. Since she wanted surgical correction of her atypical nipple for aesthetic and psychological reasons, we reconstructed the areola using transposition flaps in an S-plasty design. Results: Case 1, the excised supernumerary nipple showed following histological features. In the superficial layer, an acanthotic and hyperpigmented epithelium with elongated rete ridges was found. In the dermis, there were follicles with hairs surrounded by hypertrophic sebaceous glands. In the deepest portion, abundant secretory glomerules and excretory ducts of apocrine gland type were observed. Case 2, follow-up visits 3 months after the procedure showed a satisfactory result with good shape and projection of the nipple. Conclusion: We report two cases of aberrant mammary tissue who underwent surgical correction, including complete breast (with nipple, areola, and glandular tissue) and intra-areolar polythelia according to the Kajava's classification, and the results were satisfactory.

유두상 혈관내막 증식증의 임상적 보고

이정우,정호윤,이석종,김귀락,최강영,양정덕,조병채,Lee, Jeong-Woo,Chung, Ho-Yun,Lee, Seok-Jong,Kim, Gui-Rak,Choi, Kang-Young,Yang, Jung-Dug,Cho, Byung-Chae 대한성형외과학회 2010 Archives of Plastic Surgery Vol.37 No.3

Purpose: Intravascular papillary endothelial hyperplasia (IPEH), also known as Masson's pseudoangiosarcoma, is a rare disease which is now considered as a reactive process of the endothelium rather than a benign neoplasm. It can occur in any blood vessels in the body but more common in the head and neck region as a solitary, often tender, bluish or reddish nodule. IPEH is characterized by the development of endothelial-lined papillary projections in a vascular lumen, usually associated with thrombotic material, the endothelial cells in the papillary structures showing only slight atypia and occasional mitotic Figures, the absence of tissue necrosis. Methods: 8 patients with IPEH were enrolled in the study from 2002 to 2007. All 8 lesions were surgically excised for histopathologic diagnosis. Results: 4 patients were female. The duration of the lesions ranged from 3 months to 15 years. The tumors were first noted between the ages of 20 and 72 years. 4 patients had lesions on the head; 2 on the toe; 1 on the back; and 1 on the finger, respectively. All lesions were solitary, ranged in size from 2 mm to 27 mm. There were no recurrences. Conclusion: The clinical appearance of IPEH is not specific, presented as a primary neoplasm, and the diagnosis can be established by microscopic examination. Complete surgical excision is the best choice of therapy for patients with IPEH, and is both diagnostic and curative. Awareness of this lesion will prevent incorrect diagnosis and overly aggressive treatment.

개인 트레이의 설계와 인상채득방법이 의치 변연의 형태에 미치는 영향에 관한 연구

이정우,오상천,진태호,Lee, Jeong-Woo,Oh, Sang-Chun,Jin, Tai-Ho 대한치과보철학회 1995 대한치과보철학회지 Vol.33 No.1

The purpose of this study is to inquire about the effects of individual tray design and impression method on the border extension and contour of denture. 10 students at the dentistry college who have normal occlusion and symmetric facial form and normal facial muscle activity were selected. The tray was designed three types (large, medium, small tray). After border molding was done by dentist and operator, final impression was taken. The length of impression body and width of border were measured by a vernier caliper on the cast. The obtained results were as follows : 1. As the tray border was shortened, the length of impression body and width of border was short (P<0.01). 2. When the impression was taken with the small tray, the length of impression body was short in passive border molding than active border molding. 3. When the medium tray was used, the width of impression body was short in passive border molding than active border molding.

증예(症例) : 척수마취 후 Bupivacaine에 의해 발생한 일과성 척수 간대성근경련증

이정우 ( Jeong Woo Lee ),서명조 ( Myung Jo Seo ),최현호 ( Hyun Ho Choi ),조혜영 ( Hye Young Cho ),손지선 ( Ji Seon Son ) 전북대학교 의과학연구소 2009 全北醫大論文集 Vol.33 No.1

A 68-year-old woman underwent surgery for arthroscopic partial menisectomy. A spinal anesthesia was employed for surgery. She then received 2.8ml (14 mg) of 0.5% hyperbaric bupivacaine (Marcaine®, AstraZeneca, Sweden). The surgery proceeded uneventfully. Two hours after anesthesia involuntary, repetitive, or irregular muscle contraction in the lower extremities appeared abruptly. This disappeared two hours after onset without any neurological sequelae. The patient was followed up for six months during which she remained asymptomatic.

시금치와 엇갈이 배추 중 Triflumizole의 잔류특성 구명

이정우 ( Jeong Woo Lee ),박효경 ( Hyo Kyoung Park ),진미지 ( Me Jee Jin ),조승현 ( Seung Hyeon Jo ),임준범 ( Jun Beom Lim ),신현길 ( Hyun Gil Shin ),노현호 ( Hyun Ho Noh ),이재윤 ( Jae Yun Lee ),김진숙 ( Jin Sook Kim ),권찬혁 ( Ch 한국환경농학회 2018 한국환경농학회 학술대회집 Vol.2018 No.-

시금치와 엇갈이 배추 중 triflumizole의 잔류 특성을 구명하기 위하여 시설재배지를 임차하여 잔류 시험을 수행하였다. 시험 농약인 triflumizole (30%, WP, (주)농협케미컬)은 2,000배 희석하여 10a당 200 L의 약량으로 4개의 처리구(28-21-14, 21-14-7, 17-10-3, 14-7-0)에 7일 간격 3회 살포하였으며, 분석 시료는 수확 예정일에 일시 수확하였다. 시금치와 엇갈이 배추 중 triflumizole의 잔류 분석은 HPLC-DAD로 수행하였고, 검출한계는 모두 0.01 mg/kg이었다. 시금치와 엇갈이 배추중 triflumizole의 회수율은 검출한계의 10배와 50배 수준에서 각각 77.6-82.3과 76.0-86.8%이었다. 시금치와 엇갈이 배추 중 triflumizole의 잔류량은 각각 0.10-17.05와 0.66-4.65 mg/kg으로 시금치와 엇갈이 배추 모두 수확 예정일에 근접할수록 잔류량이 높았으며, 엇갈이 배추의 경우 작물의 증체에 의한 희석 효과로 인해 시금치보다 잔류량이 낮은 것으로 판단되었다.

논문 : 분류의 다양성과 원리: 지식의 탄생을중심으로

이정우 ( Jeong Woo Lee ),심경호 ( Kyung Ho Sim ),이상욱 ( Sang Wook Yi ) 한국과학철학회 2014 과학철학 Vol.17 No.3

세계 속의 대상을 인지하고 분류하는 작업은 필연적으로 그와 관련된 지식의성장과 함께 이루어진다. 우리는 이 점에 주목하여 우선 동서양의 사유에서 분류가 얼마나 다양한 방식으로 이루어져 왔는지를 서술한다. 그런 다음 이러한분류가 그저 다양하기만 한 것이 아니라 그 배후에 특정한 원리가 숨어 있으며,그 내재한 원리가 특정한 종류의 지식의 탄생과 깊은 관련을 갖는다는 점을 보이려 노력한다. 이 작업은 세 방향에서 이루어진다. 우선 2절에서는 서양 자연과학에서 분류가 어떻게 수행되었고 그것의 인식론적, 존재론적 의의가 무엇인지를 주로 ‘자연종’ 개념에 대한 분석을 중심으로 해명한다. 3절에서는 서양 인간과학이 대상들을 어떻게 분류했으며, 그러한 분류에서의 존재론적 재분절화가 어떻게 새로운 인간과학을 도래하게 했는지를 분석한다. 4절에서는 조선 시대에 이루어진 분류의 작업이 어떻게 성리학적 분류 체계로부터 경험적 분류체계로 이행했는지에 대해 유서(類書)를 중심으로 논의한다. 이를 통해 우리는동서양을 막론하고 얼마나 다양한 원리들에 입각해 분류가 이루어졌는지와 그러한 분류 작업이 존재론적 전환을 통해 어떻게 새로운 지식의 탄생에 기여했는지를 탐색한다. Any classification of objects in the world is necessarily linked to thebirth of its accompanied knowledge. We investigate diverse classifyingefforts in Eastern and Western thoughts, and argue that behind theconfusing diversity of alternating classification systems, we can recognizecertain principles which guided the entire classification efforts. We alsotry to show that the principles are closely related to the birth ofspecific kinds of knowledge. In order to achieve this, we look at threeareas of knowledge: current natural sciences, western human sciencesand Korean Confucianism in Chosun period. First, we examine whether‘natural kinds’ concept is adequate to explain the practice of currentnatural scientific research. Second, we analyze how western hujmanscience had been established through ‘ontological re-articulation’ of itsobjects. Lastly, we discuss how the transition from Sung Confucianisticclassification to ‘empirical’ classification was achieved in the taxonomictexts of Chosun period. We endeavored to illustrate how some guidingideas or principles had shaped the resulting classification systems ineach case.

수중건설로봇의 유압 제어 안정성 향상을 위한 이중화 설계

이정우(Jung-Woo Lee),박정우(Jeong-Woo Park),서진호(Jin-Ho Suh),최영호(Young-Ho Choi) 한국해양공학회 2015 韓國海洋工學會誌 Vol.29 No.5

In the development of an underwater construction robot, the reliability of the operating system is the most important issue because of its huge maintenance cost, especially in a deep sea application. In this paper, we propose a new redundant architectural design for the hydraulic control system of an underwater construction robot. The proposed architecture consists of dual independent modular redundancy management systems linked with a commercial profibus network. A cold standby redundancy management system consisting of a preprocessing switch circuit is applied to the signal network, and a hot standby redundancy management system is adapted to utilize two main controllers.

화질 개선을 위한 새로운 비트율 제어 알고리즘

이정우(Jeong-Woo Lee),김대희(Dae-Hee Kim),호요성(Yo-Sung Ho),홍문호(Mun-Ho Hong),이병렬(Byung-Ryul Lee),박종철(Jong-Cheul Park) 한국방송·미디어공학회 1997 한국방송공학회 학술발표대회 논문집 Vol.1997 No.-