Space holder 방법으로 제조된 다공질 타이타늄의 기계적 성질에 대한 Computed-Tomography를 이용한 유한요소해석

이동준,안동현,이병갑,정지원,오상호,이종수,김형섭,Lee, Dong Jun,Ahn, Dong-Hyun,Lee, Byounggab,Jeong, Jiwon,Oh, Sang Ho,Lee, Chong Soo,Kim, Hyoung Seop 한국분말야금학회 2013 한국분말재료학회지 (KPMI) Vol.20 No.5

In this study, porous titanium samples were manufactured by space holder methods using two kinds of urea and sodium chloride space holders. Three-dimensional pore structures were obtained by a computed-tomography (CT) technique and utilized for finite element analysis in order to investigate the mechanical properties. The CT-based finite element analyses were in better agreement with the experimental results than unit cell model-based analyses. Both the experimental and CT-based results showed the same tendency that the elastic modulus decreased with increasing the porosities. The total porosity of the bulk body plays a key role in determining the elastic modulus of porous materials.

방사선수술을 위한 노발리스 품질관리 프로토콜 개발

이동준,이경남,이석,이상훈,김대홍,Lee, Dong-Joon,Lee, Kyung-Nam,Lee, Suk,Lee, Sang-Hoon,Kim, Dae-Hong 한국의학물리학회 2010 의학물리 Vol.21 No.1

국내에서 방사선치료를 위한 선형가속기 품질관리 프로토콜은 많이 개발되어 왔지만 선형가속기를 기반으로 하는 방사선수술장비의 품질관리 프로토콜 개발은 현재까지 거의 이루어져 있지 않고 있다. 이에 본 연구는 선형가속기 기반 일체형 방사선수술장비인 노발리스의 정확도 및 정밀도를 유지하기 위하여 일간, 주간, 월간, 연간에 주기적으로 시행하여야 하는 노발리스 품질관리 프로토콜을 개발 하고 품질관리 상태의 종합적 확인을 할 수 있는 해부학적 팬텀을 제작하였다. 이를 위하여 국내외의 선형가속기를 이용하는 방사선수술 품질관리 프로토콜의 수집 및 분석을 통해 필수적인 품질관리항목과 각 항목의 허용치를 정하였다. 노발리스 품질관리 항목은 기계적 정확도 부분과 방사선 전달 부분의 2가지로 분리하고 기계적 정확도 부분은 방사선발생 장치부, 보조장치부, 그리고 미세다엽 시준기부의 3가지 부분으로 방사선 전달부분은 치료 중심점 평가와 선량학적 평가의 2가지 부분으로 나누어 작성하였다. 최종적으로 노발리스 품질관리 유지를 위하여 시행하여야 하는 일간, 주간, 월간, 연간의 노발리스 품질관리 항목 표를 완성하였다. 완성된 노발리스 품질관리항목 표는 노발리스가 방사선수술에 적합한 정확도 및 정밀도를 유지하는데 필요한 지표로서 기여 할 수 있을 것이라 생각된다. In Republic of Korea, there are many Quality Assurance protocol for general radiation treatment machine such as linac. However, Quality Assurance protocol for radiosurgery treatment system is not ready perfectly. One of the radiation treatment machine for radiosurgery, novalis system needs to suitable Quality Assurance protocol for using it right way during radiation treatment and maintaining suitable accuracy for daily, weekly, monthly and annually periods. Therefore, in this article, we develop Quality Assurance protocol for novalis system. We collected and analysed domestic and foreign novalis Quality Assurance protocol. After that, we selected essential QA items and each tolerance range for developing proper QA protocol, and we made anatomical phantom for execution of selected QA items and evaluation of overall state of QA, and then, we use this measured value as a reference. Quality Assurance items are consisted of Mechanical accuracy QA part and Radiation delivery QA part. Mechanical accuracy QA part is comprised of radiation generation machine part, assistive devices part and multi-leaf collimator part. Radiation delivery QA part is divided into radiation isocenter accuracy and dosimetric evaluation. After that, developed novalis QA tables are made by using these QA items. These novalis QA tables would be used to good standard in order to maintain apt accuracy for radiosurgery in daily, weekly, monthly and annually periods.

에이전트 기반 지휘통제 모의방법론

이동준,홍윤기,Lee, Dong-Joon,Hong, Yoon-Gee 한국시뮬레이션학회 2007 한국시뮬레이션학회 논문지 Vol.16 No.3

군의 전투 상황을 모의하는 전투 시뮬레이션 모델을 개발함에 있어서 현대전, 미래전의 핵심인 지휘통제분야에 대한 모의가 필요하다. 본 논문에서는 교전위주의 현재 워게임 모델을 개선하기위해 군의 의사결정과정인 부대지휘절차를 지능형 에이전트를 이용하는 모의방법론을 제시하였다. 계층별 지휘본부를 대리할 수 있는 다중 에이전트의 아키텍처를 설계하고 각각 에이전트의 기본적인 구조와 모의논리를 연구하였다. 본 연구는 지능형 에이전트의 적용대상을 관으로 확대하는 방법론이 될 것이고, 기본구조를 더욱 심화 발전시키면 불확실한 전장상황을 보다 정확하게 모의할 수 있는 기초가 될 것이다. This study suggests a method of command and control in modeling a combat situation. In particular, it presents the structure of an intelligent agent that may substitute for the current system of decision making in the military operation to lead a troop. Today the Korean military war game simulations emphasize on engagements, instead of command and control. This suggested principle will be a good foundation for the today and the future Korean warfare.

Special Report - 해외 주요 국가별 5G 추진 동향

이동준,Lee, Dong-Jun 한국정보통신기술협회 2018 TTA저널 Vol.2018 No.-

안티드론 시스템의 국방아키텍쳐 프레임워크 적용 연구

이동준,권형안,김지태,정길현,양상운,Lee, Dong Joon,Kwon, Hyeong Ahn,Kim, Ji Tae,Jung, Gil Hyun,Yang, Sang Woon 한국시스템엔지니어링학회 2021 시스템엔지니어링학술지 Vol.17 No.2

Recently, the rapid development of drones is increasing as a variety of threats to important facilities of the country. In order to build an anti-drone system that responds to drones with high technical characteristics, standardization is required in terms of operation, system, and technology. By applying the defense architecture framework, it contributes to the establishment of the optimal system by proposing a standardization plan for the operational and system perspectives of the anti-drone system by creating outputs equivalent to the stage of prior research on weapons systems. It is a prerequisite for building a drone system the operational concept of the anti-drone system, the definition of the drone threat, the function of each component, the interface, the definition of data flow, the system performance and effect scale, etc. Management, security officers, and equipment manufacturers of important national and public facilities on site expect that it will be used as an objective standard at the government level for the component technology of the equipment to respond to the drone threat and the performance required in the environment.

만성 심낭염의 외과적 요법

이동준,최순호,Lee, Dong-Jun,Choe, Sun-Ho 대한흉부심장혈관외과학회 1978 Journal of Chest Surgery (J Chest Surg) Vol.11 No.3

19 chronic pericarditis patients reviewed who were treated by surgical intervention in the Department of Thoracic and Cardiovascular Surgery, Chonnam University Hospital during the recent 10 years from January of 1968 to January of 1978. 2. There were 14males and 5 females in this series. Range of age varied from 110 days to 61 years. 2. There were two hospital death, one expired 2 days and another 3 days after the pericardiectomy. In both of them, myocardial damage by disease process seemed to be major contributing factor. 2. Clinical and histological study showed tuberculous origin in 8 cases, nonspecific chronic inflammatory changes in 6 cases and pyogenic infection cases in 5 patients. 2. The postoperative complications were observed in 6 cases, and the most common was cardiac arrhythmia and wound infection. 2. The extent of pericardiectomy should be confined to the left and right ventricles to correct the hemodynamic anomaly in general. The results of this procedure has been satisfactory in 89 percent of the cases. 2. Optimal myocardial function in cases of constritive pericarditis was the key to the successful outcome of this procedure.

메타모델을 이용한 플로트오버 설치 작업용 능동형 갑판지지프레임의 근사설계최적화

이동준,송창용,이강수,Lee, Dong Jun,Song, Chang Yong,Lee, Kangsu 한국산업융합학회 2021 한국산업융합학회 논문집 Vol.24 No.1

In this study, approximate design optimization using various meta-models was performed for the structural design of active type deck support frame. The active type deck support frame was newly developed to facilitate both transportation and installation of 20,000 ton class offshore plant topside. Structural analysis was carried out using the finite element method to evaluate the strength performance of the active type deck support frame in its initial design stage. In the structural analysis, the strength performances were evaluated for various design load conditions that were regulated in ship classification organization. The approximate optimum design problem based on meta-model was formulated such that thickness sizing variables of main structure members were determined by achieving the minimum weight of the active type deck support frame subject to the strength performance constraints. The meta-models used in the approximate design optimization were response surface method, Kriging model, and Chebyshev orthogonal polynomials. The results from approximate design optimization were compared to actual non-approximate design optimization. The Chebyshev orthogonal polynomials among the meta-models used in the approximate design optimization represented the most pertinent optimum design results for the structure design of the active type deck support frame.

분말 표면 조도의 3차원 레이저 분석기를 이용한 정량화와 압분성형체 강도에 미치는 영향 분석

이동준,윤은유,김하늘,강희수,이언식,김형섭,Lee, Dong-Jun,Yoon, Eun-Yoo,Kim, Ha-Neul,Kang, Hee-Soo,Lee, Eon-Sik,Kim, Hyoung-Seop 한국분말야금학회 2011 한국분말재료학회지 (KPMI) Vol.18 No.5

Green strength is an important property of powders since high green strength guarantees easy and safe handling before sintering. The green strength of a powder compact is related to mainly mechanical and surface characters, governed by interlocking of the particles. In this study, the effect of powder surface roughness on the green strength of iron powders was investigated using a transverse rupture test. Three-dimensional laser profiler was employed for quantitative analyses of the surface roughness. Two different surface conditions, i.e. surface roughness, of powders were compared. The powders having rough surfaces show higher green strength than the round surface powders since higher roughness leads increasing interlocked area between the contacting powders.

거대기종성 폐낭포증 1례 보고

이동준,김상형,Lee, Dong-Jun,Kim, Sang-Hyung 대한흉부심장혈관외과학회 1978 Journal of Chest Surgery (J Chest Surg) Vol.11 No.3

A case of Vanishing lung of right entire lung field in a man of 36 years of age was encountered at Dept. of Chest Surgery of Chonnam University Hospital. His chief complaints were cough, severe dyspnea and chest pain for about 14 years. Right pneumonectomy was done and gross finding was multiple chambered cysts of the right lung with thin epithelium. The review of the literatures was also done.

기관지확장증의 외과적 치료

이동준,김찬용,Lee, Dong-Jun,Chung, Chan-Yong 대한흉부심장혈관외과학회 1978 Journal of Chest Surgery (J Chest Surg) Vol.11 No.3

Sixty-one bronchiectatic patients were reviewed who were treated by surgical intervention in the Department of Thoracic and Cardiovascular Surgery, Chonnam University Hospital during the recent 14 years from January of 1965 to August of 1978. 1. Various pulmonary resection was performed; lobectomy was 55.5%, lobectomy and segmental resection 20.6%, bilobectomy 13.1%, lobectomy, segmental resection and thoracoplasty 4.9% and pneumonectomy was 3. 2%. 2. The most common associated disease was pulmonary Tbc, its frequency was 47.5% and next was chronic bronchitis [31%]. 3. The postoperative complication was observed in 19.6% [12 cases] and the most common was wound infection. 4. The possibility of recurrence was relatively high in the cases of residual lesion and it needs more intensive medical care. 5. The surgical result was satisfactory in 86.9% (53 cases), slight improvement in 4.9% (3 cases) and the mortality rate was 1.6% (1 case).