마그네트론 스퍼터링법으로 증착시킨 TiC 박막의 물리적, 전기적 특성에서 RF 파워의 영향

김남훈,박용섭,Kim, Nam-Hoon,Park, Yong Seob 한국전기전자재료학회 2014 전기전자재료학회논문지 Vol.27 No.7

TiC thin films were deposited on Si wafer by unbalanced magnetron sputtering (UBMS) system with two targets of graphite and titanium. During the TiC sputtering, the RF power was varied from 100 W to 175 W and the physical and electrical properties of TiC films were investigated. The hardness and rms surface roughness of TiC films were improved with increasing RF power and the maximum hardness about 24 GPa and the minimum rms surface roughness about 1.2 nm were obtained. The resistivity of TiC films was decreased with increasing RF power. Consequently, the physical and electrical properties of TiC film wewe improved with increasing RF power.

SM45C와 SCM440의 피삭성 검토에 관한 연구

김남훈,이용성,Kim, Nam-Hoon,Lee, Yung-Sung 대한기계학회 1996 大韓機械學會論文集A Vol.20 No.12

In order to clarify the effects of nonmetallic inclusion contents insteels (SM45C & SCM440) on the tool life, cutting experiment was performed under various cutting conditions. Tool life, cutting force, roughness of machined surface and cutting mechanism are examined on these two kinds of steel. The following conclusions were obtained from the analysis (1) Cutting force of the steels was not affected by chemical component and nonmetallic inclusion. (2) If the rate of amount, Ca/S has a value grater than about 0.2 and addition of less amount of Al, Mn, tool wear of tips decreasesinturning. (3) It is also proved that higher contents of nonmetallic inclusion improve roughness of the surface. (4) Less amount of Ca, higher amount of S, Mn and Al improve the chip breakability.

다층 PCB의 두께 예측을 위한 실험식 도출 연구

김남훈,한관희,이민수,김현호,신광복,Kim, Nam-Hoon,Han, Gwan-Hee,Lee, Min-Su,Kim, Hyun-Ho,Shin, Kwang-Bok 한국복합재료학회 2022 Composites research Vol.35 No.3

본 논문은 다층 PCB에 사용되는 프리프레그의 물성을 파악하여 제시한 두께 실험식을 통해 PCB의 두께를 예측하기 위한 연구를 수행하였다. 프리프레그는 물성과 동박 잔존율에 의해서 PCB 제작시 두께가 감소하기 때문에 두께 실험식을 통한 정확한 PCB의 두께 예측이 필요하다. 두께 실험식에 사용되는 프리프레그의 밀도를 파악하기 위해 질량 및 두께를 측정하여 밀도를 도출하였다. 이후 CCL을 제작하기 위해 프리프레그와 동박을 적층하여 핫 프레스기를 사용하였고 광학현미경과 마이크로미터를 사용하여 두께를 측정하였다. 또한 동박 잔존율에 따른 두께 변화를 측정하기 위해 회로밀도를 다르게 구성하여 8층 PCB를 설계하였고 두께 측정 결과와 두께 실험식으로 도출된 두께를 비교하여 두께 실험식을 검증하였다. 비교 결과 CCL의 경우 2.56%, 다층 PCB의 경우 4.48%의 오차를 보였고 이를 통해 두께실험식의 신뢰성을 확인하였다.

A549 폐 상피세포에서 합토글로빈에 의한 염증반응 조절

김남훈,이명재,김인숙,Kim Nam-Hoon,Lee Myung-Jae,Kim In-Sook 한국생명과학회 2006 생명과학회지 Vol.16 No.3

합토글로빈(Hp)은 조직손상이나 감염 등의 염증시에 혈중 농도가 증가하는 급성기반응단백질로서 주로 간에서 생합성되지만 염증을 동반한 폐에서도 발현됨이 보고되었다. 폐에서 합성되는 Hp이 염증반응에 어떤 영향을 주는지를 조사하고자, Hp을 과발현하는 폐상피세포를 사용하여 COX-2 및 염증관련 cytokine들의 발현을 조사하였다. Stable transfection 또는 transient transfection된 A549 세포에서 Hp이 잘 발현되고 있음을 확인한 후 COX-2의 발현을 측정한 결과, Hp의 과발현에 의해 COX-2 합성이 현저히 증가함을 확인할 수 있었다. 또한 Hp을 과발현하는 A549세포에 LPS ($1{\mu}g/ml$) 또는 $IL-1{\beta}$ (100 U/ml)를 각각 24시간 동안 처치하였을 때, Hp에 의한 COX-2 발현 증가는 LPS또는 $IL-1{\beta}$자극에 의해 협동적으로 증가하였다. ACP-based PCR 방법으로 염증관련 cytokine들의 발현을 측정한 결과, Hp에 의해 SPARC의 발현이 현저히 저하되는 반면에 IL-4 및 S100A1 유전자 발현은 약간 증가함을 알 수 있었다. 이러한 결과들은 폐상피세포에서 Hp이 염증반응을 활성화시키는 기전으로 작용함을 시사한다. Haptoglobin (Hp) is an acute phase protein, and its plasma level increases consistently in response to inflammation. To investigate the biological role of Hp in lung epithelial cells, the gene expressions of cyclooxygenase-2 (COX-2) and inflammatory cytokines were analyzed using human Hp gene-transfected A549 cells. Western blot analysis showed that COX-2 expression was markedly increased in Hp DNA-transfected cells (stable transfection and transient transfection) compared with that in vehicle DNA-transfected cells. When the Hp-expressing cells were treated with $1{\mu}g/ml$ of LPS or 100 U/ml of $IL-1{\beta}$ for 24 hr, the COX-2 expression was synergistically up-regulated. ACP-based PCR data demonstrated the Hp decreased SPARC expression, but increased IL-4 and S100AI expressions. These findings suggest that the Hp acts as a pro-inflammatory mediator in lung inflammation.

GMA용접용 콘택트팁의 수명 예측

김남훈,김희진,유회수,Kim Nam-hoon,Kim Hee-Jin,Ryoo Hoi-Soo 대한용접접합학회 2005 대한용접·접합학회지 Vol.23 No.4

역V형 철골 가새골조의 비탄성거동 및 내진성능향상 방안에 관한 연구

김남훈,이철호,Kim, Nam Hoon,Lee, Cheol Ho 한국강구조학회 2003 韓國鋼構造學會 論文集 Vol.15 No.5

본 논문에서는 중심가새골조 가운데 가정 널리 사용되는 역V형 철골 가새골조의 내진거동을 탄소성 후좌굴해석에 의해 고찰하고, 압축가새의 좌굴이 최초로 발생한 층에 소성화가 집중되는 약층화 현상을 완화할 수 있는 효과적 내진보강 방안을 제시하고자 하였다. 즉 좌굴이 발생한 층에 집중되는 비탄성변형을 건물전체로 재분재하는 기능을 갖는 인장재(tie bar)를 삽입하여 내진성능을 효과적으로 개선할 수 있음을 입증하였다. 아울러 압축가새의 좌굴발생 순서를 감안하여 보강 인장재를 경제적으로 설계할 수 있는 실용적 설계방안을 제시하였다. An effective seismic retrofit scheme for inverted V braced (or chevron type) steel frames was proposed by studying the redistribution of forces in the post-buckling range. The steel frames with chevron bracing are highly prone to soft story response once the compression brace buckles under earthquake loading. This paper shows that the seismic performance of such frames could be significantly improved by supplying tie bars to redistribute the inelastic deformation demand over the height of the building. A practical design method of the retrofit tie bars was also proposed by considering the sequence of buckling occurrence.

전악 발치 환자에서 캠퍼그나 트레이를 적용한 즉시의치 수복 증례

김남훈,김종은,오경철,정문규,문홍석,Kim, Nam-Hoon,Kim, Jong-Eun,Oh, Kyung Chul,Chung, Moon-Kyu,Moon, Hong-Seok 대한치과보철학회 2017 대한치과보철학회지 Vol.55 No.3

An immediate complete denture is considered as restoration for lost natural teeth, which is fabricated following the extraction of the remaining teeth. Current esthetics and function can be retained by using immediate denture without edentulous period. However, the major disadvantages of immediate denture relate to the difficulties associated with taking accurate definitive impression and predicting the results of immediate denture. In this case report, the Campagna tray technique was used to take the final impression in a 49-year-old male patient presented with all remaining teeth diagnosed as hopeless teeth. Surgical templates were used for alveoloplasty after extraction. The immediate complete dentures were then delivered. The clinical assessments of immediate dentures showed good esthetic and functional outcomes. The patient showed high level of satisfaction. 잔존 자연치의 발치가 필요한 환자에서 즉시의치의 제작을 고려해 볼 수 있다. 즉시의치를 장착함으로써 환자가 무치악으로 지내는 기간 없이 심미 및 기능을 회복해줄 수 있는 장점이 있지만 인상 채득이 어렵다는 점, 장착 후의 결과를 예측하기 어렵다는 단점이 있다. 본 증례에서는 잔존 자연치를 모두 발치해야 하는 49세 남환에서 캠퍼그나 트레이를 이용하여 최종 인상을 채득하고 수술용 형판을 이용하여 발치 및 치조골 성형술을 시행한 후, 즉시의치를 제작 및 장착하여 심미적, 기능적으로 만족할 만한 치료 결과를 보였기에 이를 보고하고자 한다.

자궁경부 악성 림프종의 경부-질 도말소견 - 1 증례 보고 -

김남훈,박찬금,고영혜,박문향,이중달,Kim, Nam-Hoon,Park, Chan-Kum,Ko, Young-Hyeh,Park, Moon-Hyang,Lee, Jung-Dal 대한세포병리학회 1995 대한세포병리학회지 Vol.6 No.1

The uterine cervix is an uncommon site of primary non-Hodgkin's lymphoma (NHL). Although the cytologic findings of NHLs are well known, most cervicovaginal smear of uterine NHLs give lower diagnostic yield than common epithelial malignancy because abnormal cells do not appear in the sample in the absence of surface ulceration. Herein, we describe cytologic findings of a case of uterine cervical NHL which was initially diagnosed by cervicovaginal smear. The tumor cells were relatively uniform, isolated, large-sized with scanty cytoplasm and round or indented nuclei. The nuclei had stippled chromatin and small nucleoli. Histologically and immunohistochemically the tumor was proven to be large cell lymphoma of T-cell lineage.

In-situ 환원/소결법을 이용한 다공성 니켈 멤브레인 가스필터의 제조 및 평가

김남훈,송한복,최성철,좌용호,Kim, Nam-Hoon,Song, Han-Bok,Choi, Sung-Churl,Choa, Yong-Ho 한국분말야금학회 2009 한국분말재료학회지 (KPMI) Vol.16 No.4

Disk type porous nickel membrane was fabricated by in-situ reduction/sintering process using compacted NiO/PMMA (PMMA; Polymethyl methacrylate) mixture at $800^{\circ}C$ in hydrogen atmosphere. The porosity (49$\sim$58%) of these membrane was investigated as an amount of PMMA additive. The thermal decomposition and reduction behavior of NiO/PMMA were analyzed by TG/DTA in hydrogen atmosphere and the activation energy for the hydrogen reduction of NiO and thermal degradation of PMMA was calculated as 61.1 kJ/mol, evaluated by Kissinger method. Finally, the filtering performance and pressure drop were measured by particle counting system.

원자층 증착장치에 의한 TiO₂ 박막 코팅된 폴리머 절연체의 표면 및 전기적 특성의 향상

김남훈,박용섭,Kim, Nam-Hoon,Park, Yong Seob 한국전기전자재료학회 2016 전기전자재료학회논문지 Vol.29 No.7

Titanium oxide ($TiO_2$) thin films were synthesized on polymer insulator and Si substrates by atomic layer deposition (ALD) method. The surface and electrical properties of $TiO_2$ films synthesized at various ALD cycle numbers were investigated. The synthesized $TiO_2$ films exhibited higher contact angle and smooth surface. The contact angle of $TiO_2$ films was increased with the increase of ALD-cycle number. Also, the rms surface roughness of films was slightly rough with the increase of ALD-cycle number. The leakage current on $TiO_2$ film surface synthesized at various conditions were uniformed, and the values were decreased with the increase of ALD-cycle number. In the results, the performance of $TiO_2$ films for self-cleaning critically depended on a number of ALD-cycle.