건설분야 드론 기술교육 참관기

남정수 한국건축시공학회 2021 건축시공 Vol.21 No.1

처음 진단된 기능성 소화불량증에 대한 치료제 선택 및 치료 효과; 단일 기관 연구

남정수,전태주,박지영 대한내과학회 2021 대한내과학회 추계학술대회 Vol.2021 No.1

Machinability of Titanium Alloy (Ti-6Al-4V) in Environmentally-Friendly Micro-Drilling Process with Nanofluid Minimum Quantity Lubrication Using Nanodiamond Particles

남정수,이상원 한국정밀공학회 2018 International Journal of Precision Engineering and Vol.5 No.1

This paper discusses the experimental characterization on micro-drilling process of titanium alloy (Ti-6Al-4V), which is one of representative difficult-to-cut materials, with the nanofluid minimum quantity lubrication (nMQL). The miniaturized machine tool system is set up, and then, a series of micro-drilling experiments are performed under compressed air (CA), pure MQL and nMQL for a comparison. For the nanofluid, nanodiamond particles with the sizes of 35 nm and 80 nm are chosen, and the base fluid is vegetable oil. For the micro-drilling process, an uncoated carbide twist drill having the diameter of 300 µm is used for drilling holes in the titanium alloy workpiece. The experimental results show that the nMQL can reduce the drilling torques and thrust forces, but its effect is more obvious at a low feed rate (10 mm/min). In addition, the edge corner radii and hole circularity errors are significantly reduced in the case of small size (35 nm) and high weight concentration (0.4 wt. %) of the nanodiamond particles at the low feed rate. It is also found that the nMQL effectively mitigates chip adhesion of drill tool and burr of drilled holes.

病주고 藥준 '생활정보 記事' 봇물

南政洙 관훈클럽 1999 관훈저널 Vol.- No.70

비상체의 충돌에 의한 고인성 섬유보강 시멘트복합체의 파괴특성

남정수,김규용,김홍섭,김정현,한상휴 한국구조물진단유지관리공학회 2015 한국구조물진단유지관리공학회 논문집 Vol.19 No.4

The aim of this study is to evaluate the fracture characteristics of ductile fiber reinforced cement based composites with 1.5 volume ratio of polyvinyl alcohol and steel fiber by high velocity impact of steel projectile. We used gunpowder impact facility to evaluate the fracture characteristics of ductile fiber reinforced cement based composites by collision of steel projectile, and the impact velocity was from about 150 to 1,000m/s. The results of evaluation on the fracture characteristics of ductile fiber reinforced cement based composites were penetration grade, which is the kinetic energy more than three times of no-fiber reinforced specimen (Plain). In addition, ductile fiber reinforced cement based composites did not occurred critical damage other than the debris. In the case of mass loss, Plain specimen was proportional to kinetic energy of steel projectile, while ductile fiber reinforced cement based composites was not significantly affected by kinetic energy of steel projectile. In particular, this tendency had a close relationship with the fracture characteristics of back side of specimens, and the scabbing inhibiting efficiency of PVA specimen was higher than S specimen. In the results of verifying relationship between front and back side calculated by local damage, scabbing occurred at the region close to the back side in the ductile fiber reinforced cement based composites unlike Plain specimen. Thus, in this study, we examined principal fracture behaviors of ductile fiber reinforced cement based composites under collision of steel projectile, and verified that impact resistance performance was improved as compared to Plain specimen. 본 연구는 폴리비닐 알코올 섬유 및 강섬유를 체적비율로 1.5% 혼입한 고인성 섬유보강 시멘트복합체에 대한 비상체의 고속충돌시험을실시하고, 충돌조건에 따른 파괴특성을 실험적으로 검토하는 것을 목적으로 하였다. 비상체의 충돌에 의한 고인성 섬유보강 시멘트복합체의 파괴특성을 평가하기 위하여 화약압력식 충격시험장치를 활용하였으며, 충돌속도의 범위는 약 150 ~ 1,000m/s로 설정하였다. 파괴특성에 대한 평가결과, 고인성 섬유보강 시멘트복합체는 섬유를 혼입하지 않은 Plain시험체의 약 3배 이상의 비상체 운동에너지가 작용하는 범위에서도 표면관입의 파괴등급으로 평가되었으며, 시험체가 파단되지 않는 내충격성능이 확인 되었다. 또한, 충돌시험 전후에 대한 시험체의 질량감소율의 경우, Plain시험체는 비상체의 운동에너지의 증가율과 비례적인 관계를 보였지만, 고인성 섬유보강 시멘트복합체는 비상체의 운동에너지의 영향을 크게 받지 않는 것으로 나타났다. 특히, 이와 같은 경향은 시험체 배면의 파괴특성과 밀접한 관계를 가지며, S시험체에 비해 PVA시험체의 배면박리 억제효율이 큰 것으로 평가되었다. 한편, 국부손상에 대한 표면관입깊이 및 배면박리깊이의 관계를 검토한 결과, 고인성 섬유보강 시멘트복합체는 Plain과 달리 시험체 단면의 중앙선을 기준으로 배면에 가까운 영역에서 배면박리가 발생하는것을 알 수 있었다. 본 연구를 통해 비상체의 충돌에 대한 고인성 섬유보강 시멘트복합체의 주요 파괴거동이 검토되었으며, Plain과 비교하여 내충격성능의 향상을 명확히 확인하였다.

Experimental Investigation on the Blast Resistance of Fiber- Reinforced Cementitious Composite Panels Subjected to Contact Explosions

남정수,김홍섭,김규용 한국콘크리트학회 2017 International Journal of Concrete Structures and M Vol.11 No.1

This study investigates the blast resistance of fiber-reinforced cementitious composite (FRCC) panels, with fiber volume fractions of 2%, subjected to contact explosions using an emulsion explosive. A number of FRCC panels with five different fiber mixtures (i.e., micro polyvinyl alcohol fiber, micro polyethylene fiber, macro hooked-end steel fiber, micro polyvinyl alcohol fiber with macro hooked-end steel fiber, and micro polyethylene fiber with macro hooked-end steel fiber) were fabricated and tested. In addition, the blast resistance of plain panels (i.e., non-fiber-reinforced high strength concrete, and non-fiberreinforced cementitious composites) were examined for comparison with those of the FRCC panels. The resistance of the panels to spall failure improved with the addition of micro synthetic fibers and/or macro hooked-end steel fibers as compared to those of the plain panels. The fracture energy of the FRCC panels was significantly higher than that of the plain panels, which reduced the local damage experienced by the FRCCs. The cracks on the back side of the micro synthetic fiber-reinforced panel due to contact explosions were greatly controlled compared to the macro hooked-end steel fiber-reinforced panel. However, the blast resistance of the macro hooked-end steel fiber-reinforced panel was improved by hybrid with micro synthetic fibers.

Investigations into the Size Effect on Plastic Deformation Behavior of Metallic Materials in Microcoining Process

남정수,이상원,김홍석 한국정밀공학회 2014 International Journal of Precision Engineering and Vol.15 No.1

In this study, the size dependence of metallic materials on the plastic deformation behavior was investigated in microcoining process. In order to conduct experimental works, a miniaturized microforming system was first developed. Then, a series of microcoining experiments were performed in a wide range of process conditions. The effects of grain size and feature size were analyzed by relating the protruded feature height to the size factor λ. It was found that the ratio of channel width to grain size is the critical factor to identify the forming performance in microcoining process. As the size factor decreased below 10, the feature size effect became prominent due to the fact that the reduced number of grains in the deformation region causes the reduced degrees of freedom in slip systems. By observing the protruded feature of the formed parts, the deformation characteristics and underlying physics associated with the miniaturization effects can be discussed.

모멘트를 변수로하는 연립방정식에 의한 구조해석

남정수,Nam, Jeong-Su 대한건축사협회 1977 建築士 Vol.1977 No.3

이왕가고전-조선무악영상과 인남순의 재현안무 영상비교연구 : 궁중정재 보상무 중심으로

남정수 차세대컨버전스정보서비스학회 2017 차세대컨버전스정보서비스기술논문지 Vol.6 No.1

Traditional dances from Chosun dynasty have been altered during the Japanese Colonial era. The main purpose of this study is to facilitate proper succession of the Royal Court dance and extend it to other creative areas through comparative analysis of how BoSangMu, a style of Royal Court Dance HyangakJungJae, has been inherited after the Chosun dynasty. This article of BoSangMu is based on the study of Sohwa (消和) 4 Year (1929) “MuYi (無儀)” comparing <Yi Royal Family’s Classical-ChosunMuakin 1931>, a historical clip of Chosun dancer with <Choreography Image of In Nam Soon’s Dance in 2015>. The study concluded that Namsung dancer’s choreography is different from the current choreography and continued research on restoring the original choreography is needed. The author hopes that this study serves as a basis for restoring and properly passing on Royal Court Dance to future generations and further creative development. 본 논문은 일제 강점기 동안 격동의 세월을 거치면서 조선왕조의 격조 높은 전통 춤사위가 많이 변형 되었다. 향악정재(鄕樂呈才)의 하나인 〈보상무〉를 중심으로 대한제국이후, 근대사회로 접어들면서 시대적인 흐름에 따라 어떻게 전승되고 계승되어져 왔는지, 비교분석하여 궁중무용의 올바른 계승과 창작영역의 확대방안을 모색하는 것이 본 연구의 목적이다. 본 연구자는 〈보상무〉에 대해 문헌의 기록인 소화(消和) 4년 (1929년) 『무의(無儀)』 를 고찰하였고, 조선 정재의 역사적인 사실적 근거로 남은 영상 자료를 바탕으로 한 《1931년 이왕가고전-조선무악》의 무동(舞童)이 추었던 영상과 현행 영상인 《2015년 인남순 재현안무》 두 영상자료를 가지고 비교분석 하였다. 이 분석을 통해서, 1) 창사(唱詞)의 상이점 2) ‘공 어르기’ ‘공 던지기‘ ’미간공읍(眉間拱邑)‘ 3가지 춤사위 동작의 상이점 3) 음악반주의 상이점 4) 복식(服飾)의 상이점 5) 상·벌(賞罰)의 상이점 총 다섯 가지의 상이점과 1) ’팔수무(八手舞)‘ 춤사위 동작 2) 공을 던지는 춤사위 동작 두 가지의 유사점을 찾아 볼 수 있었다. 본 연구로 인하여, 남성무동 춤사위와 현행춤사위가 다르고 변형되었음을 알 수 있으며, 앞으로도 지속적인 복원과 연구가 필요하다고 사료된다. 또한 궁중무용을 올곧게 전승하고 계승해 나아가 보다 심도 있는 법고창신(法古創新)의 기초자료로 활용되기를 기대한다.

버텨 온 7년, 새로운 길을 찾아야 할 때

남정수 한국비정규노동센터 2014 비정규 노동 Vol.- No.109