• 대한전기학회논문지:전기물성ㆍ응용부문C
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• 제49권1호
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• pp.70-72
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• 2000

In this paper, a spacer process for FED(Field Emission Display) was developed with the glass to glass anodic bonding technology using Al film as an interlayer and a 3.5 inch monochromatic type FED was fabricated. Holder to dislocate spacers vertically was designed with (110) Si wafer by bulk etching. Spacers, $100\mum\; width\; and\; 1000\mum$ height, were formed on anode panel by spacer to glass anodic bonding and the fabricated FED was operated for emission at 1㎸ anode voltage.

• 한국대기환경학회지
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• 제4권1호
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• pp.79-83
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• 1988

To improve working environment for the toll workers who were working at Kyungbu expressway in outskirts of Seoul and Suwon, the status of air pollution surrounding toll booth were measured from March 28 through June 14, 1986. The results were as follows: 1. The amount of TSP (total suspended particle) surrounding toll booth was directly proportional to the traffic load. The ratio of traffic load at Seoul and Suwon toll was 3.2:1 and of TSP was 2.6:1. 2. The proportion of particle larger than 5$\mum$ was 24.8 $\sim$ 34.9% of TSP at Seoul toll and 19.2 $\sim$ 32.7% at Suwon. The proportion of particle less than 2$\mum$ was 38.7 $\sim$ 51.8% of TSP at Seoul toll and 34.8 $\sim$ 54.8% at Suwon. 3. The concentration of respirable particle les than 7$\mum$ measured by personal air sampler was higher in Seoul toll booth than that of Suwon and it seems to be influenced by the exhausion of diesel engine. Especially the concentration of respirable particle of reformed toll booth with air curtain was 20% lower than unreformed one. 4. Concentration of Pb among suspended particles around Seoul toll was 5 times higher than Pb of Suwon toll. So it is considered that there were other possible pollution source of Pb beyond heavy traffic in Seoul toll area. The amount of Pb inside toll booth was extremely small but the concentration of benzo(a)pyrene showed a trend of increase according to traffic stagnation. 5. The concentration of $SO_2$ arround toll showed no difference between weekday and weekend and also showed no relation with traffic load. But the concentration of $NO_2$ was affected by traffic load.

• ETRI Journal
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• 제13권4호
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• pp.70-79
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• 1991

$In_1-x$$GA_X$$As_y$$P_1-y$ has a very wide range of applications in optoelectronic devices especially for optical communications because $In_1-x$$GA_X$$As_y$$P_1-y$ has the bandgap of the lowest dispersion ($1.3\mum$) and the lowest loss ( $1.55\mum$) of the optical fiber by changing the composition. The quality of $In_1-x$$GA_X$$As_y$$P_1-y$ epitaxial layer is believed to have a significant effect on the performance of device. The OMVPE growth conditions for the latticematched $In_1x$$GA_X$$As_y$$P_1-y$/InP were investigated. Effects of growth conditions such as V/III ratio, growth temperature, and Ga source material on the electrical and optical properties were studied. The composition, electrical and optical properities of $In_1-x$$GA_X$$As_y$$P_1-y$ were characterized using double crystal X-ray diffractometer (DCD), photoluminescence (PL), XPS(ESCA) and Hall measurement.

• 연구논문집
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• 통권25호
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• pp.105-113
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• 1995

Fresnel lenses are developed for flat optics with the optical characteristics close to aspherical lens such as sharp focusing and dispersion instead of spherical or aspherical surface. Usually, these fresnel lenses and diffraction gratings are machined by high-energy beam such as electron beam machining, but recently with the development of ultra precision machine tool and machining technology, 3-dimension micro machining becomes preferable. This study on the micro machining of fresnel lens is carried out to develop the basic technology of ultra precision micro machining. The machined lens mold will be used for the manufacturing of fresnel lens with 120mm focal distance using synthetic resin material with 1.49 refractive index(PMMA), and the shape of lens is 48mm diameter, $300\mum$ pitch and about $5-700\mum$depth of groove in brass.

• 보존과학연구
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• 통권12호
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• pp.42-62
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• 1991

A.D. 5세기 전반기경으로 추정되는 황남대총 고분에서 발굴출토된 유물 중 도금 기법이 적용된 대표적인 형태 및 용도의 유물 시료 13점을 선정 SEM-EDS 및 금속현미경에 의해 분석한 결과,시료의 도금피복 기술은 수은(Hg)에 의한 아말감(amalgam) 도금법에 의한 것으로 판명되었으며, 도금피막의 두께는 $5.99∼12.97\mum$ (단, 소지가 은인 시료 No.C는 $19.96\mum$)로 균일하고 치밀하게 도포되었다. 소지금속은 금속현미경 조직검사 결과 대부분 단조로 제조된 4.7∼11.5%의 연(Pb)을 함유하고 약 1.7% 내외의 아연(Zn)을 함유한 동합금이었다. 또한 내재된 불순물이나 기공이 매우 적은 것으로 보아 당시의 소지금속인 동합금 주조기술이 상당한 수준임을 알 수 있었다.

• 한국막학회:학술대회논문집
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• 한국막학회 1994년도 추계 총회 및 학술발표회
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• pp.80-80
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• 1994

세라믹막을 이용한 oil 폐수 처리의 기초 연구로서 정밀여과용 세라믹막의 제조와 oil(kerosene)-in-water 타입 에멀젼에 대한 막분리 효율이 연구되었다. 정밀여과 막으로서는 압출(extrusion)법으로 성형하여 제조한 $\alpha$-알루미나 튜브(평균 기공크기 0.9 $\mum$)와 이들 튜브(담체)내부에 $ZrO_2$ 또는 $Al_2O_3$ 다공성 박막을 코팅한 2층 구조의 복합막들을 사용하였다. 담체의 높은 투과율 ($1700 l/m^2\cdot h$ at $\Deltap = 1$ atm)을 어느정도 유지하면서 막분리 효율을 증대시킬 수 있는 새로운 슬러리 코팅법이 개발되엇으며, 코팅후 950-1300$\circ$C 에서 열처리한 코팅층의 두께와 평균 기공크기는 각각 5 - 20 $\mum$정도 이었다. 정밀여과막의 특성평가를 위하여 막 제조조건에 따른 코팅층의 두께 및 결함유무를 SEM으로 일단 관찰한 후에 Bubble Point Test와 Mercury Porosimeter를 이용하여 측정한 최대 및 평균 기공반경과 물의 투과량으로부터 막 전체에 대한 결함 유무와 결함의 허용한도등을 비교 분석하였다.

• 전자통신동향분석
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• 제14권1호통권55호
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• pp.13-23
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• 1999

평면형 광소자 제조공정 중 실리카 식각공정 기술은 일반적으로 잘 알려진 반도체 식각공정 기술과 달리 $8\mum$이상을 식각할 수 있는 높은 식각률과 그에 따른 마스크 물질의 높은 선택비를 필요로 하며, 특히 광 손실을 줄이기 위하여 표면 및 측면의 조도를 줄일 수 있는 공정기술을 필요로 한다. 본 고에서는 $8\mum$이상의 실리카 채널 도파로 형성시 요구되는 식각특성 중 식각률과 식각선택비 및 플라즈마 소스에 대하여 알아보고, 유도결합프라즈마(inductively coupled plasma)를 사용한 실리카막의 식각특성과 최근 진행되고 있는 희토류 첨가 실리카막 식각공정에 대하여 소개한다.

• 대한전기학회논문지:전기물성ㆍ응용부문C
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• 제49권9호
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• pp.523-526
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• 2000

A dual gate trench emitter IGBT structure is proposed and studied numerically using the device simulator MEDICI. The on-state forward voltage drop latch-up current density turn-off time and breakdown voltage of the proposed structure are compared with those of the conventional DMOS-IGBT and trench gate IGBT structures. The proposed structure forms an additional channel and increases collector current level resulting in reduction of on -state forward voltage drop. In addition the trench emitter increases latch-up current density by 148% in comparison with that for the conventional DMOS-IGBT and by 83% compared with that for the trench gate IGBT without degradation in breakdown voltage when the half trench gate width(Tgw) and trench emitter depth(Ted) are fixed at $1.5\mum\; and\; 2\mum$, respectively

• 연구논문집
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• 통권22호
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• pp.127-139
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• 1992

The mechnial properties such as fracture strength, ductility and fatigue strength of Cu shape memory alloy are lower than those of Ti-Ni SMA, because of their high elastic anisotropy and large grain size. And in order to improve the mechanical property of Cu SMA, some techniques such as casting method by addition of refining element, powder metallurgy and rapid solidification process have been studied on the refinement of the grain size of Cu SMA. This study was carried out to refine the grain size of CuAlNi SMA by applying the melt spinning method. According to this study, the conclusions are as follows; - grain size of the melt-spun ribbon was about $1\mum$ - there was not change in grain size, although increasing of hot pressing temperature -grain size of the hot-extruded specimen was about $30-40\mum$, it is more refiner than that of castings

• 산업경영시스템학회지
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• 제45권1호
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• pp.10-19
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• 2022

Recently, the Defense Advanced Research Projects Agency(DARPA) in the United States is studying a new concept of war called Mosaic Warfare, and MUM-T(Manned-Unmanned Teaming) through the division of missions between expensive manned and inexpensive unmanned aircraft is at the center. This study began with the aim of deriving the priority of autonomous functions according to the role of unmanned aerial vehicles in the present and present collaboration that is emerging along with the concept of mosaic warfare. The autonomous function of unmanned aerial vehicles between the presence and absence collaboration may vary in priority depending on the tactical operation of unmanned aerial vehicles, such as air-to-air, air-to-ground, and surveillance and reconnaissance. In this paper, ACE (Air Combat Evaluation), Skyborg, and Longshot, which are recently studied by DARPA, derive the priority of autonomous functions according to air-to-air collaboration, and use AHP analysis. The results of this study are meaningful in that it is possible to recognize the priorities of autonomous functions necessary for unmanned aircraft in order to develop unmanned aerial vehicles according to the priority of autonomous functions and to construct a roadmap for technology implementation. Furthermore, it is believed that the mass production and utilization of unmanned air vehicles will increase if one unmanned air vehicle platform with only essential functions necessary for air-to-air, air-to-air, and surveillance is developed and autonomous functions are expanded in the form of modules according to the tactical operation concept.