마그네트론 스퍼터링 증착법을 사용하여 순수한 질소 플라즈마에 의해 성막된 고경도 TiN_X 박막의 역학적 특성

이창현,이병로,배강,박창환,김화민,Lee, Chang-Hyun,Rhee, Byung-Roh,Bae, Kang,Park, Chang-Hwan,Kim, Hwa-Min 한국전기전자재료학회 2017 전기전자재료학회논문지 Vol.30 No.8

TiN (titanium nitride) films were prepared using the RF magnetron sputtering technique. The films were deposited by pure $N_2$ plasma sputtering. Their mechanical properties, such as nano-indentation hardness, friction coefficient, and surface wettability, have been investigated. X-ray diffraction (XRD) studies revealed that the orientation of $TiN_X$ films changed towards the (111) orientation with decreasing working pressure due to a strong compressive stress during deposition. The strongest TiN (111) orientation was found when the film was deposited at a working pressure of 1 Pa. This film showed the largest hardness (16 GPa) and smallest friction coefficient (0.17) among the studied samples. Moreover, this film was found to be accompanied by a water-repellent surface with water contact angle more than $100^{\circ}$.

적응빔 형성을 이용한 다중경로 환경 내 저고도 해상표적의 고각 추적 정확도 향상

이창현(Chang-Hyun Lee),전상미(Sang-Mi Chon),박종국(Jongkuk Park),나형기(Hyung-Ki Na),김상현(Sang-Hyun Kim) 한국전자파학회 2021 한국전자파학회논문지 Vol.32 No.2

본 논문에서는 다중경로 환경에서 적응빔 형성 기법을 이용한 저고도 해상표적의 추적 정확도 향상 방법에 대해 제안하고, 이를 아날로그 빔 형성 능동위상배열(AESA: active electronically scanned array) 레이다 환경에 적용하여, 제안 방법이 반복 없는 적은 연산으로 비교적 높은 정확도의 표적 고각을 산출할 수 있음을 확인하였다. 제안 방법은 모노펄스(monopulse) 기울기 제어를 위한 기존의 적응빔 형성 제한조건에 부엽 제어 조건을 추가하고, 고각 변화 정도가 작은 저고도 해상표적의 특징을 활용하여 추적 정확도를 개선하였다. 또한 추적 정확도 향상을 위해 다양한 적응빔 형성 기법을 적용해 보고, 그 결과를 비교분석하였다. A method to improve the tracking accuracy of low-altitude sea targets is proposed using an adaptive beamforming algorithm in a multipath environment. It is confirmed that the target elevation can be estimated with relatively high accuracy without repetitive calculation using the proposed method in analog beamforming active electronically scanned array radar. The proposed method improves the tracking accuracy by adding a side-lobe suppression condition to the existing adaptive beamforming constraint for monopulse inclination control while accounting for the characteristics of the low-altitude sea target with less elevation change. In addition, various adaptive beamforming algorithms were applied to the proposed method, and the results were compared and analyzed to optimize tracking accuracy.

흰쥐에서 WGA-HRP와 pseudorabies virus를 이용한 정관의 신경로에 대한 연구

이창현,정옥봉,고병문,이봉희,김수명,김인식,양홍현,Lee, Chang-Hyun,Chung, Ok-Bong,Ko, Byung-Moon,Lee, Bong-Hee,Kim, Soo-Myung,Kim, In-Shik,Yang, Hong-Hyun 대한수의학회 2003 大韓獸醫學會誌 Vol.43 No.1

This experimental studies was to investigate the location of PNS and CNS labeled neurons following injection of 2% WGA-HRP and pseudorabies virus (PRY), Bartha strain, into the ductus deferens of rats. After survival times 4-5 days following injection of 2% WGA-HRP and PRV, the rats were perfused, and their brain, spinal cord, sympathetic ganglia and spinal ganglia were frozen sectioned ($30{\mu}m$). These sections were stained by HRP histochemical and PRY inummohistochemical staining methods, and observed with light microscope. The results were as follows ; 1. The location of sympathetic ganglia projecting to the ductus deferens were observed in pelvic ganglion, inferior mesenteric ganglion and L1-6 lwnbar sympathetic ganglia. 2. The location of spinal ganglia projecting to the ductus deferens were observed in T13-L6 spinal ganglia. 3. The PRY labeled neurons projecting to the ductus deferens were observed in lateral spinal nucleus, lamina I, II and X of cervical segments. In thoracic segments, PRY labeled neurons were observed in dorsomedial part of lamina I, II and III, and dorsolateral part of lamina IV and V. Densely labeled neurons were observed in intermediolateral nucleus. In first lumbar segment, labeled neurons were observed in intermediolateral nucleus and dorsal commisural nucleus. In sixth lumbar segment and sacral segments, dense labeled neurons were observed in sacral parasympathetic nuc., lamina IX and X. 4. In the medulla oblongata, PRV labeled neurons projecting to the ductus deferens were observed in the trigeminal spinal nuc., A1 noradrenalin cells/C1 adrenalin cells/caudoventrolateral reticular nuc., rostroventrolateral reticular nuc., area postrema, nuc. tractus solitarius, raphe obscurus nuc., raphe pallidus nuc., raphe magnus nuc., parapyramidal nuc., lateral reticular nuc., gigantocellular reticular nuc.. 5. In the pons, PRV labeled neurons projecting to the ductus deferens were ohserved in parabrachial nuc., Kolliker-Fuse nuc., locus cooruleus, subcooruleus nuc. and AS noradrenalin cells. 6. In midbrain, PRV labeled neurons projecting to the ductus deferens were observed in periaqueductal gray substance, substantia nigra and dorsal raphe nuc.. 7. In the diencephalon, PRV labeled neurons projecting to the ductus deferens were observed in paraventricular hypahalamic nuc., lateral hypothalamic nuc., retrochiasmatic nuc. and ventromedial hypothalamic nuc.. 8. In cerebrum, PRV labeled neurons projecting to the ductus deferens were observed in area 1 of parietal cortex. These results suggest that WGA-HRP labeled neurons of the spinal cord projecting to the rat ductus deferens might be the first-order neurons related to the viscero-somatic sensory and sympathetic postganglionic neurons, and PRV labeled neurons of the brain and spinal cord may be the second and third-order neurons response to the movement of smooth muscles in ductus deferens. These PRV labeled neurons may be central autonomic center related to the integration and modulation of reflex control linked to the sensory and motor system monitaing the internal environment. These observations provide evidence for previously unknown projections from ductus deferens to spinal cord and brain which may be play an important neuroanatornical basic evidence in the regulation of ductus deferens function.

한국재래산양의 이개근에 대한 해부학적 연구

이창현,이흥식,이인세,Lee, Chang-hyun,Lee, Heungshik S.,Lee, In-se 대한수의학회 1989 大韓獸醫學會誌 Vol.29 No.3

This study was carried out to investigate the origin, insertion, direction of muscle fibers and structure of the ear muscles of the Korean native goat. The description was based on the dissection of fifteen the Korean native goats with embalming fluid. The results were as follows: 1. The ear muscles of the Korean native goat were composed of the M. zygomaticoauricularis, M. scutuloauricularis superficialis, M. scutuloauricularis profundus, M. frontoscutularis, M. interscutularis, M. parietoauricularis, M. cervicoscutularis, M. cervicoauricularis superficialis, M. cervicoauricularis medius, M. cervicoauricularis profundus, M. auricularis profundus posterior and M. parotidoauricularis. 2. The M. frontoscutularis clearly seperated into temporal and frontal parts in 6 cases. 3. The M. scutuloauricularis profundus clearly separated into major and minor parts. 4. The M. zygomaticoauricularis blended with the M. parotidoauricularis near its insertion, but not with the M. scutuloauricularis.

인천대교 선박 충돌에너지 분석을 통한 선박의 통항안전 속력에 관한 연구

이창현,이홍훈,김득봉,김철승,박성현,Lee, Chang-Hyun,Lee, Hong-Hoon,Kim, Deun-Bong,Kim, Chol-Seong,Park, Seong-Hyun 해양환경안전학회 2016 해양환경안전학회지 Vol.22 No.6

인천대교는 인천국제공항과 송도국제도시를 연결하는 길이 13.38 km, 경간 800 m의 대형 교량으로 시간당 73.8(vessel/hour)척의 선박이 통항하고 있다. 본 연구에서는 인천대교 건설 시 설계되었던 인천대교 충돌방지공의 안전기준을 바탕으로 인천대교를 통항하는 선박의 중량에 따른 안전한 통항 속력을 제시하고자 한다. 연구방법은 AASHTO LRFD에서 제시한 선박 충돌에너지와, 선박 충돌 속도, 수리동적질량계수를 고려하여 통항 선박의 안전 속력을 제시하고자 한다. 인천대교의 충돌방지공은 10만DWT급 선박이 10노트로 통항 할 수 있도록 설계되었다. 본 연구에서는 대상선박(30만DWT급)의 선속조건 및 화물 상태의 비교 분석을 통하여 각각의 충돌에너지에 따른 제한 속력을 산정하는 방식으로 통항 선박의 안전 속력을 제시하였다. 또한 해당 수역의 조위에 따른 통항 선박의 안전 속력을 추가적으로 분석하였다. 대상선박(30만DWT급)을 통한 연구 결과 최대 15만DWT급 선박이 평균조위 이상의 수심에서 최대 7노트 속력으로 운항이 가능한 것으로 나타났으며, 경하상태(Ballast condition)에서는 최대 8노트의 속력으로 인천대교를 통항할 수 있는 것으로 분석되었다. Incheon Bridge is 13.38 km long with an 800 m span, connecting Incheon International Airport and Songdo International City, Per hour 73.8 vessels navigate this space. The purpose of this study was to suggest a safe passing speed based on the displacement of a vessel based on the safety criteria of Incheon Bridge's anti-collision fence, which was designed during its initial construction. As AASHTO LRFD suggested, vessel collision energy, vessel collision velocity, and the hydrodynamic mass coefficient were considered to derive a safe vessel traffic speed. Incheon Bridge's anti-collision fence was designed so that 100,000 DWT vessels can navigate at a speed of 10 knot. This research suggests a safe speed for vessel traffic through a comparative analysis of an experimental ship's (300,000 DWT) speed and cargo conditions, regulation speed has been calculated according to the collision energy under each set of conditions. Additionally, safe traffic vessel's safe speed was analyzed with reference to tidal levels. Results from the experimental ship showed that a vessel of maximum 150,000 DWT is able to pass Incheon Bridge at a maximum of 7 knots with an above average water level, and is able to pass the bridge with a maximum of 8 knots under ballast conditions.

초광역경제권(MegaloPolis)으로 본 한국-일본간 경제협력에 관한 연구 -부산-후쿠오카현 초광역경제권 형성을 중심으로-

이창현 ( Chang Hyun Lee ),김경희 ( Kyoung Hee Kim ) 한국통상정보학회 2009 통상정보연구 Vol.11 No.1

I wish to examine plan about megalopolis formation with Japan and Busan, possess location condition that can be injured to center hub of North-east Asia. First for this, through competitive analysis of Korea and Japan in industrial structure, I will search competition relation. Second, examine what exports and specialization industry of two area are, through industrial structure of Busan and Kyushu area of Japan. Third, to form megalopolis, wish to present what business belt that can bind two area. Fourth, I wish to present preview point about this study in the conclusion. Examine from 2004 to 2007 through exports, degree of trade join(combination), index of trade specialization degree, index of Revealed comparative advantage, and etc, for analysis of this study how in changed industry competitive between two countries or two area have changed.

실리콘 제조 공정에서 발생한 실리콘 슬러지를 활용한 용강 SiC계 승온제 제조 연구

이창현,이상로,박만복,구연수,이만승,Lee, Chang-Hyun,Lee, Sang-Ro,Park, Man-Bok,Koo, Yeon-Soo,Lee, Man-Seung 한국자원리싸이클링학회 2017 資源 리싸이클링 Vol.26 No.6

반도체 산업의 실리콘(Si) 제조과정에서 실리콘과 실리콘 카바이드(SiC)를 포함하는 폐 슬러리가 발생하게 된다. 폐 슬러리는 단순히 시멘트로 고형화하여 보관하거나 매립하는 방법이 있지만, 본 연구에서는 제강공정의 부원료인 승온제로 사용하는 방안이 제시되었다. 폐 슬러리를 정제하여 분말을 만들어 SiC계 슬러지 브리켓으로 재활용하였다. SiC계 슬러지 브리켓은 화학적 성분을 분석하고 투입시기와 투입량에 따른 승온제 특성을 관찰하였다. 이 결과 SiC계 슬러지 브리켓은 제강공장에서 저비용과 고효율로 용강온도를 높이는 효과가 있었다. Most Waste slurry is produced in the process of silicon manufacturing for semiconductor industry, containing silicon (Si) and silicon carbide (SiC). Waste slurry is simply stored with solidifying by cement or buried. On the other hand, it was suggested in this study that the waste slurry should be used for heating source as supplementary material in steel making process. The waste slurry was refined and pulverized, which was recycled into SiC-based sludge briquette. Chemical composition for SiC-based sludge briquette was analyzed and the feature of heating source was observed in accordance with the injection time and input amount. As a result, SiC-based sludge briquette in terms of low cost and high efficiency had an effect on increasing liquid steel temperature in steel making plants.

운동에너지 탄에 따른 전투시스템 내의 순간화재발생에 대한 해석적 연구

이승철(Lee Seung-Chul),전우철(Jeon Woo-Chul),이해평(Lee Hae-Pyeong),이헌주(Lee Heon-Joo),이창현(Lee Chang-Hyun) 제어로봇시스템학회 2012 제어로봇시스템학회 합동학술대회 논문집 Vol.2012 No.7

본 연구는 외부 위협탄에 의한 전투시스템의 취약성을 분석하기 위한 선행연구로써, 운동에너지 탄의 종류에 따른 가상의 전투차량 내부에 적재포탄에서 순간화재발생 여부에 대한 전산해석을 수행하였다. 본 해석은 Autodyn 프로그램을 사용하였으며 순간화재발생을 판단하기 위해 Lee-Tarver ignition and growth model을 이용하였다. 본 계산에서 운동에너지 탄은 type A와 type B 두 가지로 설정하였고, 고폭탄은 COMPB, TNT 및 PBX9404를 설정하였다. 전산해석 결과, 고폭탄의 재질이 TNT와 PBX9404가 COMPB 재질보다 순간화재발생 확률이 상당히 높음을 알 수 있고 type B의 운동에너지 탄이 type A 보다 순간화재발생 확률이 다소 높음을 알 수 있었다.

A Study on the Introduction Plan of the Places of Refuge in Domestic Areas based on the Analysis of Foreign Cases

이창현,박성현,정중식,Lee, Chang-Hyun,Park, Sung-Hyeon,Jeong, Jung-Sik The Korean Society of Marine Environment and safet 2012 해양환경안전학회지 Vol.18 No.3

해상에서 발생하는 대형 해양사고는 재산상의 손실뿐만 아니라 심각한 해양환경 오염피해를 유발하고 있다. 국제해사기구(IMO)에서는 해양사고 발생으로 인한 2차적인 해양환경오염 피해를 최소화하기 위하여 "원조를 필요로 하는 선박"에 선박 피난처를 제공하도록 결의서 Res. A.949(23)로 채택하였다. 해상교통 환경 요소 등에 의한 데이터를 바탕으로 종합적인 측면에서 잠재적 위험평가를 실시하여 위험도의 레벨이 일정한 크기를 초과하게 되면 피난처로 지정될 필요가 있고, 선박의 통항안전성, 혼잡도 및 위험도의 정량화/표준화된 기술을 기반으로 선박 피난처 지정 시스템 기술개발이 시급하다. 또한, 선박 피난처를 지정하는 문제는 연안국의 자연환경을 보호하기 위한 국가 정책과 밀접한 관련이 있기 때문에 관련 법안을 마련하는 것이 최우선이다. 본 연구에서는 선박 피난처를 지정 운영하고 있는 외국 사례 분석을 통해 효율적인 국내 선박 피난처 도입방안을 마련하고자 하였다. A huge marine accident causes a loss of valuable lives, property and the serious marine environment pollution. IMO adopted resolution A.949(23) to provide Places of Refuge(PoR) to 'Ship in need of assistance', which is to minimize the secondary environmental pollution caused by marine accidents. If the level of risk exceeds a certain range, it is necessary to be designated as Places of Refuge(PoR) after evaluation of potential risk, which is based on the database of several marine environmental factors. Also, it is necessary to develop skills about quantification/standardization of vessel traffic safety, complexity and risk. Because there is the close relation between the problem of designating Places of Refuge(PoR) and the policy of nation for protecting the natural environment of coastal state, it is important to prepare related legislation. In this paper, introduction of Places of Refuge(PoR) in domestic areas have been suggested based on the analysis of several foreign designating cases.

플라즈마 에칭공정에 따른 산화물 박막의 광촉매 표면 특성

이창현,서성보,오지용,진익현,손선영,김화민,Lee, Chang-Hyun,Seo, Sung-Bo,Oh, Ji-Yong,Jin, Ik-Hyeon,Sohn, Sun-Young,Kim, Hwa-Min 한국전기전자재료학회 2015 전기전자재료학회논문지 Vol.28 No.5

$WO_3$, $SiO_2$, and $TiO_2$ films with hydrophilic property are deposited by rf-magnetron sputtering. Their wettability is strongly depends on the presence or absence of the oxygen plasma etching on the glass substrates. The $TiO_2$ film of 50 nm-thick on the plasma etched glass shows a water contact angle (WCA) below $5^{\circ}$ which means a super-hydrophilic surface. However, WCA values are gradually degraded when the films are exposed under atmosphere, especially $WO_3$. In order to improve hydrophilic property, the degraded films can be again recovered by UV illumination for 10 sec using UV-light and the $TiO_2$ film shows a super-hydrophilic surface about $3^{\circ}$.