간질에 의한 Mongolian gerbil 줄무늬체에서의 미세관 관련 단백질들의 변화

안성진(Sung-Jin An),박승국(Seung-Kook Park),황인구(In-Koo Hwang),원무호(Moo Ho Won),강태천(Tae-Cheon Kang) 대한해부학회 2002 Anatomy & Cell Biology Vol.35 No.5

유전적인 간질 모델 중에 하나인 gerbil의 줄무늬체에서 미세관 관련 단백질 1A (microtubule-associated protein 1A, MAP1A)와 미세관 관련 단백질 2 (microtubule-associated protein 2, MAP2) 면역반응의 변화를 관찰한 결과 다음과 같은 결과를 얻었다. 정상군의 경우, MAP1A 면역반응성은 줄무늬체의 꼬리-조가비핵의 신경세포체에서 미약하게 관찰된 반면, 간질전 군 (pre-seizure group)에서는 신경세포체 및 신경가지에서 강하게 관찰되었다. 그러나, 간질발작 30분 후에는 신경세포체의 MAP1A 면역반응이 감소하기 시작하여, 간질발작 3시간 후에는 정상군과 유사한 반응성을 나타내었다. MAP2 면역반응성은, MAP1A의 경우와 유사하여, 정상군에 비해 간질전군에서 강한 염색성을 나타내었다. 간질발작 30 분 후에는 신경세포체 및 신경망에서의 MAP2 면역반응성이 감소하기 시작하여, 간질발작 3시간 후에는 매우 미약한 MAP2 면역반응성이 관찰되었다. 그러나 이러한 MAP1A 및 MAP2 면역반응성의 감소는 간질발작 12시간 후에 모두 간질전군 수준으로 회복되었다. 이러한 결과는 간질군에서 MAPs 면역반응성의 증가 및 간질발작에 따른 MAPs 면역반응성의 감소는 줄무늬체에서의 MAPs 발현의 변화는 간질발작과 매우 밀접한 연관성이 있음을 시사한다. 따라서, 간질군에서의 MAPs 면역반응성의 변화는 간질발작에 의한 신경세포손상을 복구하기 위한 일종의 보상작용으로 추측된다. The present study involves a chronological and comparative analysis of both microtubule-associated protein 1A (MAP1A) and microtubule-associated protein 2 (MAP2) immunoreactivities in the striatum of both seizure resistant (SR) and seizure sensitive (SS) gerbil. The MAP1A immunoreactivity is weakly detected in perikarya of SR gerbils. However, MAP1A immunoreactivity is more accumulated in perikarya and dendrites in the pre-seizure group. At 30 min postictal, MAP1A immunoreactivity in the perikarya is decreased. At 3 hr postictal, MAP1A immunoreactivity in perikarya and dendrites is similarly decreased to the level of SR gerbils. The MAP2 immunoreactivity is weakly detected in the perikarya and dendrites of SR gerbils. However, MAP2 immunoreactivity is more accumulated in perikarya and dendrites. In particular, the neuropil between unstained fiber tracts obviously contains strong MAP2 immunoreactivity. At 30 min postictal, MAP2 immunoreactivity isn’t almost observed in striatum. At 3 hr postictal, the MAP2 immunoreactivity is not different in the 30 min post-seizure groups but is only observed in the neuropil. However, at 12 hr postictal, the decrease of both MAP1A and MAP2 immunoreactivities had recovered to the pre-seizure level of SS gerbils. These results suggest that MAPs immunoreactivity in the striatum is different in SR and SS gerbils, and that this difference may be the results of seizure activity in this animal.

신교통시스템 도입을 위한 차량시스템에 관한 고찰

정수영(Chung Su-Young),안성진(An Sung-Jin),김표종(Kim Pyo-Jong) 한국철도학회 2009 한국철도학회 학술발표대회논문집 Vol.2009 No.5월

최근 국내에서도 대도시의 도로 교통 혼잡과 그로 인한 환경오염으로 인해 신교통시스템의 중요성이 증대하고 있는 가운데 기존 지하철의 과중한 건설비 및 운영비 부담을 대체할 수단으로서 신교통시스템의 도입에 대해 적극적인 정책을 수립하고 있는 실정이다. 현재의 도시교통의 문제점을 해결하고 미래 도시교통의 모습을 새롭게 만든다는 의미에서 신교통시스템에 대한 분명한 인식과 도입방안에 대한 검토가 시급한 시점으로, 신교통 차량시스템은 효율적인 서비스 제공 및 교통문제 해결을 위해 다양한 형태로 발전해 왔으며, 전용 주행로를 갖는 철도시스템의 장점인 정시성 및 안전성과 버스의 장점인 유연성을 만족시킬수 있는 시스템으로 개발되어 왔다. 본 논문에서는 신교통시스템 도입시 차량시스템 선정시 고려사항 및 기존노면 교통수단과 공용으로 주행로를 사용할 수 있는 차량시스템으로 저상굴절버스, 노면전차, GRT(Guided Rapid Transit,유도 고속차량) 시스템의 해외운행 사례 및 시스템을 비교, 장단점을 중심으로 고찰 하고자 한다. As the increased importance is placed on the new transit systems owing to the environmental pollution caused by the road traffic congestion, the policy for the introduction of the new transit systems as an alternative solution to ease the heavy burden of the construction expenses is being actively established. Since the explicit recognition of such transit systems and the review on the method of its adoption have been a pressing matter in the light of reducing the pending traffic congestion, the development of the rolling stock systems in modes of new transportation has been made in various ways taking into consideration the regional circumstances to alleviate traffic congestion, and offer a more efficient service with the application of their intrinsic characteristics. Such systems also have been developed as a mix of punctuality for railway systems operating on the runway and flexibility for buses. This paper, therefore, deals in more detail with 3 modes of systems such as low-floor articulated buses, GRT(Guided Rapid Transit) and tram cars, and studies the overseas cases of the operation of those systems involving both negative and positive aspects.

Ag/Sn/Ag 샌드위치 구조를 갖는 Backside Metallization을 이용한 고온 반도체 접합 기술

최진석,안성진,Choi, Jinseok,An, Sung Jin 한국마이크로전자및패키징학회 2020 마이크로전자 및 패키징학회지 Vol.27 No.1

The backside metallization process is typically used to attach a chip to a lead frame for semiconductor packaging because it has excellent bond-line and good electrical and thermal conduction. In particular, the backside metal with the Ag/Sn/Ag sandwich structure has a low-temperature bonding process and high remelting temperature because the interfacial structure composed of intermetallic compounds with higher melting temperatures than pure metal layers after die attach process. Here, we introduce a die attach process with the Ag/Sn/Ag sandwich structure to apply commercial semiconductor packages. After the die attachment, we investigated the evolution of the interfacial structures and evaluated the shear strength of the Ag/Sn/Ag sandwich structure and compared to those of a commercial backside metal (Au-12Ge).

고체 전구체-폴리에틸렌을 이용한 그래핀 성장

류종성,안성진,Ryu, Jongseong,An, Sung Jin 한국재료학회 2019 한국재료학회지 Vol.29 No.5

Chemical vapor deposition method using $CH_4$ gaseous hydrocarbons is generally used to synthesize large-area graphene. Studies using non-gaseous materials such as ethanol, hexane and camphor have occasionally been conducted. In this study, large-area graphene is synthesized via chemical vapor deposition using polyethylene as a carbon precursor. In particular, we used a poly glove, which is made of low-density polyethylene. The characteristics of the synthesized graphene as functions of the growth time of graphene and the temperature for vaporizing polyethylene are evaluated by optical microscopy and Raman spectroscopy. When the polyethylene vaporizing temperature is over $150^{\circ}C$, large-area graphene with excellent quality is synthesized. Raman spectroscopy shows that the D peak intensity increased and the 2D peak intensity decreased with increasing growth time. The reason for this is that sp3 bonds in the graphene can form when the correct amount of carbon source is supplied. The quality of the graphene synthesized using polyethylene is similar to that of graphene synthesized using methane gas.

물유리를 이용한 나노실리카 제조 시 pH가 미치는 영향

최진석,안성진,Choi, Jin Seok,An, Sung Jin 한국재료학회 2015 한국재료학회지 Vol.25 No.4

Synthesis of nano-silica using water glass in a Sol-Gel process is one of several methods to manufacture nano-silica. In nano-silica synthesized from water glass, there are various metal impurities. However, synthesis of nano-silica using water glass in a Sol-Gel process is an interesting method because it is relatively simple and cheap. In this study, nano-silica was synthesized from water glass; we investigated the effect of pH on the synthesis of nano-silica. The morphology of the nanosilica with pH 2 was flat, but the surface of the nano-silica with pH 10 had holes similar to small craters. As a result of ICP-OES analysis, the amount of Na in the nano-silica with pH 2 was found to be 170 mg/kg. On the other hand, the amount of Na in the nano-silica with pH 10 was found to be 56,930 mg/kg. After calcination, the crystal structure of the nano-silica with pH 2 was amorphous. The crystal structure of the nano-silica with pH 10 transformed from amorphous to tridymite. This is because elemental Na in the nano-silica had the effect of decreasing the phase transformation temperature.

이온 주입법을 이용한 ZnO 박막의 As 도핑

최진석,안성진,Choi, Jin Seok,An, Sung Jin 한국재료학회 2016 한국재료학회지 Vol.26 No.6

ZnO with wurtzite structure has a wide band gap of 3.37 eV. Because ZnO has a direct band gap and a large exciton binding energy, it has higher optical efficiency and thermal stability than the GaN material of blue light emitting devices. To fabricate ZnO devices with optical and thermal advantages, n-type and p-type doping are needed. Many research groups have devoted themselves to fabricating stable p-type ZnO. In this study, $As^+$ ion was implanted using an ion implanter to fabricate p-type ZnO. After the ion implant, rapid thermal annealing (RTA) was conducted to activate the arsenic dopants. First, the structural and optical properties of the ZnO thin films were investigated for as-grown, as-implanted, and annealed ZnO using FE-SEM, XRD, and PL, respectively. Then, the structural, optical, and electrical properties of the ZnO thin films, depending on the As ion dose variation and the RTA temperatures, were analyzed using the same methods. In our experiment, p-type ZnO thin films with a hole concentration of $1.263{\times}10^{18}cm^{-3}$ were obtained when the dose of $5{\times}10^{14}$ As $ions/cm^2$ was implanted and the RTA was conducted at $850^{\circ}C$ for 1 min.

폴리스타이렌을 이용한 그래핀 합성 및 산화 붕소가 그래핀 합성에 미치는 영향

최진석,안성진,Choi, Jinseok,An, Sung Jin 한국재료학회 2018 한국재료학회지 Vol.28 No.5

Graphene is an interesting material because it has remarkable properties, such as high intrinsic carrier mobility, good thermal conductivity, large specific surface area, high transparency, and high Young's modulus values. It is produced by mechanical and chemical exfoliation, chemical vapor deposition (CVD), and epitaxial growth. In particular, large-area and uniform single- and few-layer growth of graphene is possible using transition metals via a thermal CVD process. In this study, we utilize polystyrene and boron oxide, which are a carbon precursor and a doping source, respectively, for synthesis of pristine graphene and boron doped graphene. We confirm the graphene grown by the polystyrene and the boron oxide by the optical microscope and the Raman spectra. Raman spectra of boron doped graphene is shifted to the right compared with pristine graphene and the crystal quality of boron doped graphene is recovered when the synthesis time is 15 min. Sheet resistance decreases from approximately $2000{\Omega}/sq$ to $300{\Omega}/sq$ with an increasing synthesis time for the boron doped graphene.

물유리를 이용한 고순도 나노실리카 제조

최진석,이현권,안성진,Choi, Jin Seok,Lee, Hyun-Kwuon,An, Sung Jin 한국재료학회 2014 한국재료학회지 Vol.24 No.5

Silica nano-powder (SNP) is an inorganic material able to provide high-performance in various fields because of its multiple functions. Methods used to synthesize high purity SNP, include crushing silica minerals, vapor reaction of silica chloride, and a sol-gel process using TEOS and sodium silicate solution. The sol-gel process is the cheapest method for synthesis of SNP, and was used in this study. First, we investigated the shape and the size of the silica-powder particles in relation to the variation of HCl and sodium silicate concentrations. After drying, the shape of nano-silica powder differed in relation to variations in the HCl concentration. As the pH of the solution increased, so did the density of crosslinking. Initially, there was NaCl in the SNP. To increase its purity, we adopted a washing process that included centrifugation and filtration. After washing, the last of the NaCl was removed using DI water, leaving only amorphous silica powder. The purity of nano-silica powder synthesized using sodium silicate was over 99.6%.

Web 트래픽 기반의 전용 회선 대여곡 결정에 관한 연구

서상현,최영수,안성진,정진욱,Seo, Sang-Hyeon,Choe, Yeong-Su,An, Seong-Jin,Jeong, Jin-Uk 한국정보처리학회 2000 정보처리논문지 Vol.7 No.s8

이 논문에서는 Web 사이트를 설계할 때 응답시간과 관련해서 고려되어야 할 요수 중[10,15,16], 인터넷 연결 회선의 대역폭 결정에 참조될 수 있는 자료를 제시한다. 이를 위해 다양한 환경에서 Web 세션 도착율에 따른 응답시간과 회선 이용율의 변화를 관찰하고, 이를 통해 특정 대역폭의 회선에 대해 Web 서비스가 한계 응답시간 내에 보장될 수 있는 Web 세션 도착율의 임계치를 구한다. [15,16]. 이 논문에서는 데이터 수집을 위해 실험 네트워크를 구성하고, 자체적으로 구현한 패킷 생성기를 이용하여 세션 도착율의 변화에 따른 Web 트래픽을 시뮬레이션한다. 응답시간은 패킷 생성기가 생성한 각각의 HTTP(Hyper-Text Transfer Protocol)요청 패킷이 전송되는 시점부터 HTTP응답 메시지가 도착하는 시점까지의 경과된 시간으로 구하고, 회선 이용율은 SNMP(Simple Network Management Protocol)를 이용해 자체 구현한 데이터 수집기로 구한다[3]. 이 실험의 결과는, Web 사이트를 설계할 때 네트워크 전문가가 아니더라도 인터넷 연결 회선의 대역폭 결정 문제를 해결하는데 쉽고 유용하게 참조될 수 있다.

비정상 트래픽 분석을 위한 네트워크 모니터링 기반의 네트워크 성능 분석 시스템

김시홍,구자환,김승해,최장원,안성진,Kim, So-Hung,Koo, Ja-Hwan,Kim, Sung Hae,Choi, Jang-Won,An, Sung-Jin 한국융합보안학회 2004 융합보안 논문지 Vol.4 No.3

Computational Grid나 Data Grid와 같은 대규모 분산 시스템은 장애 탐지, 성능 측정, 성능튜닝, 성능 예측, 스케줄링, 보안 분석 등의 작업을 위해 많은 량의 모니터링 데이터를 필요로 한다. 네트워크 특성을 나타내는 지표들은 네트워크 모니터링 시스템을 통해 얻어질 수 있으며 시스템에 의해 축적된 자료는 상기한 작업의 정확한 분석을 돕는다. 본 논문에서는 네트워크 모니터링 시스템의 한 형태로 네트워크 모니터링기반의 네트워크 성능 및 보안 분석 시스템을 소개한다. 본 시스템은 이용자 중심으로 네트워크 성능 및 보안 데이터를 제공하며, 이용자가 원격지의 네트워크 특성을 측정 환경에 따라 변화해 가며 측정할 수 있게 함으로써 해당 원격지의 네트워크 서비스를 가늠해 볼 수 있게 한다. Large distributed systems such as computational and data grids require that a substantial amount of monitoring data be collected for various tasks such as fault detection, performance analysis, performance tuning, performance prediction, security analysis and scheduling. to cope with this problem, they are needed network monitoring architecture which can collect various network characteristic and analyze network security state. In this paper, we suggest network performance and security analysis system based on network monitoring. The System suggest that users can see distance network state with tuning network parameters.