• 한국항공우주학회지
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• 제32권6호
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• pp.148-152
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• 2004

• 한국위성정보통신학회논문지
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• 제9권3호
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• pp.1-4
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• 2014

무선통신 시스템은 동일채널 또는 인접채널에서 동작하는 무선 송신기에 의해서 간섭을 받는다. 때문에 새로운 서비스를 도입할 경우에는 도입하는 시스템과 기존 시스템 상호 간에 미치는 간섭분석을 통해서 서로 공존할 수 있는 기술기준을 마련해야 한다. FTS(Flight Termination System)는 공공의 안전을 보장하고 발사체의 비정상적인 임무수행을 막기 위해서 사용된다. 최근에는 보안성을 높이고 여러 발사체나 비행체에서 동시에 운용할 수 있는 차세대 FTS에 대한 연구가 진행 중이며, EFTS(Enhanced FTS)는 이러한 목적에 적합하다. 본 논문에서는 간섭신호가 EFTS의 성능에 미치는 영향을 분석하였다. EFTS의 변조방식으로는 비동기 DPSK(Differential PSK)와 비동기 CPFSK(Continuous Phase FSK)를 고려하였고, 간섭원으로는 FMCW(Frequency Modulated Continuous Wave) 신호와 펄스레이더를 고려하였다. 간섭원의 전력은 FMCW의 경우 원신호보다 20.3dB가 작고, 펄스레이더의 경우에는 원신호보다 19.1dB가 작은 것으로 설정하고 간섭 영향을 시뮬레이션하였으며, 시뮬레이션 결과 FMCW 간섭의 경우 $E_b/N_o$가 1dB 정도 악화되었고, 펄스레이더 간섭 신호의 경우 $E_b/N_o$가 약 0.5dB 악화되었다.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2004년도 추계학술대회 논문집 Vol.17
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• pp.620-623
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• 2004

In this study, the discharge characteristic of FTS (Facing Targets Sputtering) apparatus was investigated using metal target paramagnetic and ceramic targets such as Zn, Al, $ZnO:Al(Al_2O_3)$, ITO. Threshold voltage and stable stage of discharge show different with target species. Compare with commercial sputtering apparatus, the FTS apparatus is a high-speed sputter method that promotes ionization of sputter gas by screw and reciprocate moving high-speed ${\gamma}$electrons which arrays two targets facing each other, inserts plasma arresting magnetic field to the parallel direction of the center axis of both targets, discharged from targets and accelerated at the cathode falling area. Especially, we notice that the FTS method using ceramic target has stable discharge characteristic even by DC power source.

• 항공우주기술
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• 제3권2호
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• pp.104-115
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• 2004

본 논문에서는 FTS 수신기(Receiver)의 기저대역(Baseband)부에 적용되어 신호에 포함되는 불필요한 잡음성분을 제거하기 위한 용도의 저역통과필터(Low-Pass Filter)와 톤(Tone)신호를 검출해 내기 위한 톤 필터로 적용 가능한 여러 종류의 필터에 대해 고찰하였고, 이를 바탕으로 Simulation을 통해 적용 가능성을 검토하였다. 서로 다른 형태의 필터는 각각의 목적과 용도에 따라 특성의 차이가 있으므로 어느 하나의 필터 특성이 좋다는 절대적인 기준은 없고 적용하려는 목적과 성능의 필요성에 따라 필터의 형태가 결정되는 상대적인 기준에 의해 결정되게 된다. 이에 따라 본 논문에서는 적용되는 부품 소자의 수를 줄여 무게의 경량화와 소형화를 얻으면서도 요구하는 성능을 만족시킬 수 있는 최적의 필터형태를 제시하였다.

• 한국전기전자재료학회논문지
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• 제17권9호
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• pp.979-982
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• 2004

The ZnO thin films were prepared by the FTS (facing target sputtering) system, which enables to provide high density plasma and a high deposition rate at a low working gas pressure. We introduced the AZO thin film in order to improve the crystallographic properties of ZnO thin film because of the AZO(ZnO:Al) thin film has an equal crystal structure to the ZnO thin film. ZnO/AZO thin films were deposited at a different oxygen gas flow ratio, R.T. 2mTorr working pressure and a 0.8A sputtering current. The film thickness and c-axis preferred orientation of ZnO/AZO/glass thin films were measured by ${\alpha}$-step and an x-ray diffraction (XRD) instrument. In the results, we could prepare the ZnO thin film with c-axis preferred orientation of about 6$^{\circ}$ on substrate temperature R.T. at O$_2$ gas flo rate 0.5.

• 한국표면공학회지
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• 제29권6호
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• pp.824-828
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• 1996

Co-based alloy thin films ddeposited by fcing targets sputtering(FTS) were investigated for use in high-density magnetic recording media to determine how their magnetic properties are dependent on the sputtering conditions, and thus to find appropriate parameters that allow the sputtering and thin films to meet the specificiations for magnetic properties. FTS can discharge at lower working gas pressure than other sputtering methods such as dcmagnetron sputteing because the plasma is sufficiently confined by a magnetic field applied perpendicular to both of the target planes, which results in plasma-free substrates. Co-Cr-Ta films were deposited by FTS on glass and silicon substrates at substrate temperature between room temperature and $350^{\circ}C$, and at argon gas pressure between 0.1 and 10mTorr. The films were also deposited on polyimide tapes at substrate temperature of $130^{\circ}C$ and argon gas pressure of 1 mTorr. The effective advantages of Ta as an additional element were investigated, using the same films on the tapes. As a result of the experiment, it was found that better magnetic properties were obtained in the ranges of higher temperature and lower argon gas pressure with background pressure in thr range of $1.5 \times 10^{-6}$ Torr. Ta addition at 2 to 4 atomic percent almost havled the Co-Cr grain sizes, indicating that Ta addition at an appropriate atomic percent is effective for improving the microstructure and characteristics of Co-Cr films.

• Natural Product Sciences
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• 제21권4호
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• pp.282-288
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• 2015

Viriditoxin is a fungal metabolite isolated from Paecilomyces variotii, which was derived from the giant jellyfish Nemopilema nomurai. Viriditoxin was reported to inhibit polymerization of FtsZ, which is a key protein for bacterial cell division and a structural homologue of eukaryotic tubulin. Both tubulin and FtsZ contain a GTP-binding domain, have GTPase activity, assemble into protofilaments, two-dimensional sheets, and protofilament rings, and share substantial structural identities. Accordingly, we hypothesized that viriditoxin may inhibit eukaryotic cell division by inhibiting tubulin polymerization as in the case of bacterial FtsZ inhibition. Docking simulation of viriditoxin to ${\beta}-tubulin$ indicated that it binds to the paclitaxel-binding domain and makes hydrogen bonds with Thr276 and Gly370 in the same manner as paclitaxel. Viriditoxin suppressed growth of A549 human lung cancer cells, and inhibited cell division with G2/M cell cycle arrest, leading to apoptotic cell death.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2008년도 하계학술대회 논문집 Vol.9
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• pp.439-440
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• 2008

Indium Zinc Tin Oxide (IZTO) thin films for transparent thin film transistor (TTFT) were deposited on glass substrate at room temperature by facing targets sputtering (FTS). The FTS system was designed to array two targets facing each other and forms the high- density plasma between. Two different kinds of targets were installed on FTS system. One is ITO ($In_2O_3$ 90wt.%, $SnO_2$ 10wt.%), the other is IZO($In_2O_3$ 90wt%, ZnO 10wt%). The conductive and optical properties of IZTO thin film is determined depending on variation of DC power and working pressure. Therefore, IZTO thin films were prepared with different DC power and working pressure. As-deposited IZTO thin films were investigated by a UV/VIS spectrometer, an X-ray diffractometer (XRD), a scanning electron microscopy (SEM), a Hall Effect measurement system. As a result, all IZTO thin films deposited on glass substrate showed over 80% of transmittance in visible range (400~800 nm) at $O_2$ gas flow rate. We could obtain IZTO thin films with the lowest resistivity $5.67\times10^{-4}$ [$\Omega{\cdot}cm$] at $O_2$ gas flow rate 0.4 [sccm).

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2008년도 하계학술대회 논문집 Vol.9
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• pp.423-424
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• 2008

A facing target sputtering (FTS) equiment is fabricated and its process characteristics are investigated to search for the possibility of applications to film passivation system for organic light emitting diodes (OLEDs). We report that the FTS system can prepare a high quality $ZrO_2$ films with a dense micro structure and an excellent uniformity less than 5% and a high transmittance over an average 80% in the visible range. We suggest that the FTS is one of the suitable deposition techniques for the thin film passivation layer of OLEDs and the gas barrier layer of polymer substrate.

• 융합보안논문지
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• 제13권4호
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• pp.109-115
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• 2013

인터넷망을 이용한 정보 전달의 대표적인 수단인 이메일 서비스 등을 통한 보안위협이 급증하고 있다. 이러한 보안위협의 공격 경로는 첨부된 문서파일에 악성코드를 삽입하고, 해당 응용프로그램의 취약점을 이용하여 사용자의 시스템을 감염시키게 된다. 따라서 본 연구에서는 파일 전송과정에서 위장악성코드의 감염을 차단하기 위해, 논리적 망 분리인 FTS(File Transfer System)를 이용한 무결성 검증 및 행위기반 탐지 시스템을 제안하고, 기존의 보안기법과의 비교 및 검증하고자 한다.