고유진동수를 이용한 정림사지 5층 석탑의 구조모델

이성민,이기학,박선우,서만철,이찬희,Lee, Sung-Min,Lee, Ki-Hak,Park, Sun-Woo,Suh, Man-Chul,Lee, Chan-Hee 한국공간구조학회 2008 한국공간구조학회지 Vol.8 No.5

요즘은 비선형해석과 유한요소해석이 가능하며 또 불연속면을 모델링을 통해 구현할 수 있도록 개발된 컴퓨터 프로그램이 개발되어 사용되고 있다. 그러나 석조구조물의 물성을 파악하지 않고서는 이러한 프로그램을 이용하여 실제거동을 예측하기가 매우 곤란하다. 이를 위해 석재와 석재의 접촉부의 강성의 변수를 사이부재를 가정하는 방식으로 수행하였으며, 실제 고유진동수를 측정하고, 석탑을 다자유도계 구조물로 가정하여 고유치 해석을 한 다음 이론상 고유진동수와 실제고유진동수가 일치하도록 접촉면의 강성을 조절하는 방식으로 모델링을 수행하였다. 연구를 위해 정림사지 오층석탑을 대상으로 구조모델링을 실시하였다. 본 연구결과는 석탑형 문화재에 대해 범용 프로그램을 이용한 구조모델링을 가능하도록 함으로써 주요 석탑형 문화재의 연직하중 뿐 아니라 진동이나 횡력에 대한 구조안전성 평가를 하는 과정에서도 유용할 것으로 기대된다. Multi-layered stone masonry monuments, such as stone pagoda can be modeled as a multi-degrees of freedom system. The dynamic behavior of these structures are mainly influenced by contour condition of contacting surface of stones. In this case the mass of the system can be easily estimated, mean while the estimation of stiffness at junction is not simple. In this paper a method for estimating the spring constant at the contacting surface of stone in proposed. This paper describes a method of computational modelling technique for structural analysis of stone pagodas using measurement of natural frequency and eigenvalue analysis. For this purpose Five story stone pagoda in Cchongnimsa site was selected as a model.

한국의 공업화건축 공법 도입활용과정 분석을 통한 3D 프린팅기술 개발 방향성 연구

이성민,이필원,조후영,이재헌,Lee, Sung-Min,Lee, Pil-Won,Cho, Hoo-Young,Lee, Jae-Heon 한국공간구조학회 2017 한국공간구조학회지 Vol.17 No.4

This paper aims at finding some lessons applicable to successful implementation of 'The 3D Printing R/D Project' through both examining the process of adopting overseas industrialized housing production technological knowhow by home builders during the 1970's~1980's period and thereafter until now the various efforts to adjust the technologies efficiently to the Korea's unique situation. Some meaningful lessons can be summarized as follows; I) Deep understanding of 3DP technological know-why along with its inheritance, II) Readjusting of R/D period and goals(cf. Global leader Winsun's 15 years experiment), III) Restructuring for more collaborative R/D B&E system among participating researchers IV) Fostering 3DP expert-engineers and technicians from the early stage, V) Clearing legal barriers in users' adopting 3DP methods necessary, VI) Development of appropriate building material besides concrete. Therefore, it is highly recommended that the above-mentioned 6 lessons positively accepted and applied to the Research Implementation Plan in due course, especially by KICT consortium and KAIA under the guidance of Ministry of Land, Infrastructure and Transport.

고양이 3종(FPV, FHV, FCV) 불활화 백신의 효과

이성민,윤인중,최환원,이근좌,이경열,김무강,Lee, Sung-min,Yoon, In-joong,Choi, Hwan-won,Lee, Keun-jwa,Lee, Kyoung-youl,Kim, Moo-kang 대한수의학회 2005 大韓獸醫學會誌 Vol.45 No.3

This study tested the effect of a trivalent (feline panleukopenia; FPV, feline viral rhinotracheitis; FHV, feline calicivirus infection; FCV) inactivated vaccine in cats. The vaccine was tested for the safety in guinea pigs, mice and cats. Also, it was tested for the efficacy in cats. The vaccine was inoculated to cats at 7~9 and 10~12 weeks of age (conventional schedule) and the serological response to vaccination was assessed and was compared to the unvaccinated group. All cats were bled by jugular venipuncture for FPV, FHV and FCV specific serological test (virus neutralizing antibody, VN) at 7~9, 10~12 and 13~15 weeks. After last bleeding, all cats were inoculated with each virus (FPV : orally $2ml\;10^{7.5}\;TCID_{50}/ml$, FHV : nasally $1ml\;10^{7.0}\;TCID_{50}/ml$ and FCV : nasally $1ml\;10^{7.0}\;TCID_{50}/ml$). The Vaccine verified excellent protective effect in guinea pigs, mice and cats. The VN antibody titers of the unvaccinated group cats against FPV, FHV and FCV were <2~16, on the other hand the vaccinated group cats were $512{\sim}{\geq}4096$, 64~1024 and 64~1024, respectively. When all cats were challenged with virulent viruses, the survival rates of the vaccinated group cats were over 80%, while the survival rates of the unvaccinated group cats were less 20%. The typical clinical signs were not observed in the vaccinated group cats, but the typical clinical signs and histopathological lesions were observed in the unvaccinated group cats. As the result of tests, the VN values obtained in this study appeared to be high enough to protect cats from viral challenges. The trivalent (FPV, FHV, and FCV) inactivated vaccine seemed to be very effective, for prevention of feline viral diseases (FPV, FHV, and FCV).

1달 간격으로 재발생한 동양안충의 인체감염 1예

이성민,신규민,김동희,강병남,Sung Min Lee,Kyu Min Shin,Dong Hee Kim,Byung Nam Kang 대한안과학회 2010 대한안과학회지 Vol.51 No.6

Purpose: To report a relapsed case of an intra-conjunctival Thelazia callipaeda infestation within one month. Case summary: A 59-year-old female patient presented with symptoms of itching and a sense of foreign substance in her left eye, which she had been experiencing for several days. Conjunctival hyperemia and follicle multiplication along with ten actively moving worms were identified and were extracted with forceps. The symptoms disappeared until 25 days later, when they recurred and five additional worms were extracted. All of the extracted worms were confirmed to be Thelazia callipaeda and the patient’s symptoms disappeared after the final extraction. Conclusions: More than one month of follow-up observation is required for human infection by Thelazia callipaeda due to the post- extraction growth of the larva. J Korean Ophthalmol Soc 2010;51(6):895-898

스페이스프레임의 볼조인트 접합부 파괴모드에 관한 실험적 연구

이성민,김민숙,김대영,송창영,강창훈,Lee, Sung-Min,Kim, Min-Sook,Kim, Dae-Young,Song, Chang-Young,Kang, Chang-Hoon 한국공간구조학회 2007 한국공간구조학회지 Vol.7 No.6

대공간구조에서 접합부의 신뢰도는 매우 중요하다. 접합부에 사용되는 고력볼트의 나사부 유효단면적은 축부단면적보다 작고 볼트 축부에 락핀용 구멍이 있기 때문에 볼트 나사부 또는 락핀용 구멍에 응력집중 현상이 발생하여 취성 파단이 발생할 우려가 높다. 특히 접합부는 직렬형 구조로 이루어져 있다. 따라서 접합부에서의 극한상황시 파괴유형은 필히 취성파괴를 피해야 하며 연성파손으로 유도해야 한다. 따라서 본 연구에서는 볼 조인트 접합부의 소성변형능력을 향상시키고 현장에서 발생할 수 있는 시공오차의 흡수가 가능하도록, 볼트의 나사부나 핀부의 취성파단 없이 소성변형능력 향상을 목표로 하였다. 에너지흡수형 볼트를 사용함으로써 소성변형능력이 향상된 스페이스 프레임의 접합상세를 제안하였다. The hole for the insertion of the pin in the shank is exist at ball joint connection of the space frame. It brings about the brittle fracture caused by stress concentration. Consequently it cannot expect the deformation performance or energy absorption performance from ball joint connection. In this study we developed a new connection details which will increase the plastic deformation performance at ball joint connection and can absorb the error in construction, which expect the plastic deformation performance at the reduced shank without brittle fracture at the screw of bolt and pin. Also it's capacity is verified by the performance in numerical analysis and test. We confirmed bolt's plastic deformantion performance through controled shank and pin's area.

논문편 : 20대와 40대 여성의 상반신 체형과 유방형태 분석 및 분류

이성민,손희순 ( Sung Min Lee,Hee Soon Sohn ) 대한가정학회 1996 Human Ecology Research(HER) Vol.34 No.6

한국어 초, 중, 종성 혼돈 단음절 최소대립쌍 (CVC)에 대한 정상 성인의 지각경계 연구

이성민,임덕환,Lee, Sung-Min,Lim, Duk-Hwan 한국음향학회 2010 韓國音響學會誌 Vol.29 No.5

청각 범주지각 (categorical perception)은 언어적 자극과 관련되어 나타나는 특징적 현상이다. 본 연구에서는 임상적으로 혼돈되기 쉬운 한국어 초성, 중성, 종성 최소대랍쌍의 지각경계에 관한 분석을 하였다. 이를 위해서 단음절어 최소대립쌍(consonant-vowel-consonant, CVC)인 /곰-공/, /논-눈/, /돈-논/을 물리적 에너지 관점에서 11가지 단계 (index)로 구분하여 변환하였다. 그리고, 정상 성인 (40명)을 대상으로 하여 지각경계 패턴, 지각경계 기울기, 지각경계 폭, 비우위 지수(non-dominant factor) 분포를 분석하였다. 이 결과에서 대립쌍들은 범주지각 과정에서 대립쌍 상호간에서 상대적인 차이가 있음을 보여 주었다. 본 자료에서는 중성 최소대립쌍의 경우가 범주지각이 가장 낮게 나타났으며, 이러한 분석 과정이 청각기능 평가 등에 응용 가능성이 있음을 확인할 수 있었다. Categorical perception has been noted as characteristic properties of linguistic stimuli. In this study, Korean monosyllabic minimal pairs (consonant-vowel-consonant, CVC) were analyzed to understand perception boundaries between clinically confusing words. An efficient scheme has been developed to systematically synthesize temporal transition waveforms (11 steps) from one word to the target word for the pairs of /gom/-/gong/, /non/-/noon/, and /don/-/non/. The corresponding slopes, widths, and non-dominant factors of perception boundaries were analyzed for the total of 40 young normal subjects (20 males and 20 females). Results showed that there were relative pattern differences among confusing monosyllabic minimal pairs under categorical perception. For instance, the vowel difference within CVC pairs led to the lowest boundary performance in this experiment set. Data also indicated the potential application of the overall procedure for evaluating auditory functions and assisting rehabilitation programs.

장거리 가스수송 배관의 배관건전성 확보 대책

이성민,Lee, Sung-Min 한국유체기계학회 2003 한국유체기계학회 논문집 Vol.6 No.2

복숭아씨살이좀벌(Eurytoma maslovskii)의 기주, 발생양상 및 산란특성

이성민,김세진,양창열,신종섭,홍기정,Lee, Sung-Min,Kim, Se-Jin,Yang, Chang Yeol,Shin, Jong-Seop,Hong, Ki-Jeong 한국응용곤충학회 2014 한국응용곤충학회지 Vol.53 No.4

매실의 낙과 피해를 일으키는 복숭아씨살이좀벌은 경기도, 충청남북도, 전라남북도 지역의 매실과 살구, 그리고 중국산 복숭아 종자에서 확인되었다. 복숭아씨살이좀벌은 땅에 떨어진 핵과류의 핵 속에서 유충 상태로 월동하고, 노숙유충은 4월 중순까지, 번데기는 3월 하순에서 4월 하순까지 관찰되었으며, 성충은 4월 하순~5월 상순 사이에 90% 이상이 우화하는 것으로 조사되었다. 암컷 성충은 핵이 경화되기 이전 씨앗이 액상일 때 과실 씨앗의 외피 바로 밑에 산란하였으며, 산란관의 길이가 5 mm를 넘지 않아 산란이 가능한 매실의 크기는 직경이 2 cm를 넘지 않았다. 하나의 과실에 최대 5개의 알이 관찰되었으며, 알 기간은 2일을 넘지 않았다. 부화한 유충은 먼저 고형화되는 배로 이동하여 이를 섭식하면서 성장하는데 이 과정에서 유충들 사이의 경쟁으로 인해 한 마리의 유충만 생존하였다. 6월 상순경 피해를 받은 과실의 대부분이 부패증상을 보이며 낙과하였다. 땅에 떨어진 과실의 핵 속에서 이듬해 봄까지 노숙유충으로 월동하였다. We investigated the host fruit, seasonal occurrence, and oviposition habits of the eurytomid wasp, Eurytoma maslovskii that cause Japanese apricot fruit drops. This eurytomid wasp was found to occur in Gyeonggi-do, Chungcheongbuk-do, Chungcheongnam-do, Jeollanam-do, and Jeollabuk-do in Korea, and it attacked seeds of Japanese apricot, apricot, and peach. Overwintered larvae were observed until mid April, inside the stone of Japanese apricots. Pupation took place between late March and late April. More than 90% of the adult wasps emerged between late April and early May. The female wasps laid eggs just under the seed coat before endocarp hardening. The length of the wasp ovipositor was at least 5 mm, and hence, the diameters of fruits for oviposition would not exceed 2 cm. We observed up to five eggs per fruit, and the egg stage did not last for more than two days. Newly hatched larvae moved to the embryo, which is the first part that forms in a seed, and feeds on this. Larval competition occurs during this time; in this study, only one larva survived and matured. Thus, from the larva cycle of the wasp, most of the damaged fruits would have fallen by early June, before the harvest period.

드로잉 공정에서 소재 유입에 영향을 미치는 인자에 관한 연구

이성민,신진희,김경아,이춘규,Lee, Sung-Min,Shin, Jin-Hee,Kim, Kyung-A,Lee, Chun-Kyn 한국금형공학회 2022 한국금형공학회지 Vol.16 No.2

Sheet Metal Forming by Press Forming Process takes a lot of time and cost from mold design to manufacturing. Therefore, all of die-makers are continuously conducting research to reduce the number of mold processes or the size of blanks to reduce costs. In the case of Forming complex shapes such as automobile component, wrinkles and cracks occur, so draw beads are used. Draw beads play an important role in suppressing the inflow of materials and minimizing the size of blanks. Factors that affect material flow include draw bead, blank holding pressure, lubricant, and surface roughness of punch and die. Most of the factors affect friction. In this study, after classifying circular beads and rectangular beads in cylindrical drawing molds using the AutoForm analysis program, the factors affecting the material inflow were considered.