• Proceedings of the Korean Society of Agricultural Engineers Conference
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• 2005.10a
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• pp.306-312
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• 2005

Gates for the purpose of drainage are classified following the types of structure as: Radial Gate, Sluice Gate, Rolling Gate, Drum Gate. In many cases of the reclamation project the sluice type of gates are applied. Different from this general trend, however the radial type of gate was adopted in the Saemangeum project. In this case the discharge coefficients which are used for the sluice type of gate was applied. To estimate the correct amount of discharge which will be evacuated through the gates, therefore the proper discharge coefficients should be estimated before the operation of the gates. The discharge coefficients were estimated through the physical hydraulic modeling, and we got the results as: $0.72{\sim}0.84$ for the submerged condition on the both sides of upstream and downstream, $0.62{\sim}0.83$ for the free surface condition on the downtream side only, and $1.04{\sim}1.12$ for the free surface condition on the both sides of upstream and downstream. The discharge coefficients obtained from the experiments are greater than those of the sluice gates in the design criteria. From the results of the study we may expect that in the Saemangeum project the radial gates could evacuate larger amount of discharge than the originally designed discharge, so that we may sure that the Saemangeum gates have enough capability to control the evacuation of water not only in the usual period but also in the flooding season.

• Journal of the Korean housing association
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• v.20 no.4
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• pp.1-9
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• 2009

In this study, an examination and an analysis are carried out on the forms and components of the access spaces of hotel entrances from the front gate of five star hotels in Jejudo, Korea. The results of the study are as follows. In terms of the arrangement of the hotel, city hotels with a relatively narrow site area are influenced by site shape, while resort hotels with a relatively wide site area are affected by the environment. However, the location of the front gate was determined by the access road from the outside. Therefore, forms of access space are related to the front gate, which is governed by the access road, and to the entrance, which is determined by the hotel arrangement. If the front gate is in line with the hotel entrance, a straight line and the hotel are arranged vertically to the front gate(side arrangement) or the hotel is arranged horizontally to the front gate, but if the entrance is not in line with the front gate, it appears as a curved shape. However, those who use their own cars have a variety of choices for access route depending on the location of the parking lot.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.18 no.3
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• pp.34-39
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• 2004

This research investigated the influence on the 4 cell of DC discharge on the side of the discharge characteristic. This DC discharge cells are that composes AND gate of AND gate PDP newly proposed. As for the discharge starting voltage of this discharge cell of 4 pieces, it has been understood that there is deeply a relation up to the space charge generated from the discharge of adjoining discharge cell through the experiment. The discharge voltages which had become each discharge cell optimizations from the experiment result were decided. Moreover, the width of the margin of two AND input voltages is wide and the AND function occurs clearly. However, it has been qualitatively understood that it is difficult enough to obtain the operation margin of the DC priming discharge used to address discharge of PDP.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.46 no.12
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• pp.58-65
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• 2009

In this paper, we designed high voltage gate drive IC including dead time circuit in which capacitors controlled rising time and falling time, and schimitt-triggers controlled switching voltage. Designed High voltage gate drive IC improves an efficiency of half-bridge converter by decreasing dead time variation against temperature and has variable dead time by the capacitor value. and its power dissipation, which is generated on high side part level shifter, has decreased 52 percent by short pulse generation circuit, and UVLO circuit is designed to prevent false-operation. We simulated by using Spectre of Cadence to verify the proposed circuit and fabricated in a 1.0um process.

• Proceedings of the Korean Vacuum Society Conference
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• 1999.07a
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• pp.162-162
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• 1999

초고주파 집적회로의 핵심소자로 각광을 받고 있는 GaAs MESFET(MEtal-emiconductor)은 게이트 형성 공정이 가장 중요하며, WNx 내화금속을 이용한 planar 게이트 구조의 경우 임계전압(Vth:threshold voltage)의 균일도가 우수할 뿐만 아니라 특히 Side-wall을 이용한 self-align 게이트는 소오스 저항을 줄일 수 있어 고성능의 소자 제작을 가능하게 한다.(1) 본 연구의 핵심이 되는 Side-wall을 형성하기 위하여 PECVD법에 의한 SiOx 박막을 증착하고, 건식식각법을 이용하여 SiOx side-wall을 형성하였다. 이 공정을 이용하여 소오스 저항이 낮고 임계전압의 균일도가 우수한 고성능의 self-aligned gate MESFET을 제작하였다. 3inch GaAs 기판상에 이온주입법에 의한 채널 형성, d.c. 스퍼터링법에 의한 WNx 증착, PECVD법에 의한 SiOx 증착, MERIE(Magnetic Enhanced Reactive Ion Etcing)에 의한 Side-wall 형성, LDD(Lightly Doped Drain)와 N+ 이온주입, 그리고 RTA(Rapid Thermal Annealing)를 사용하여 활성화 공정을 수행하였다. 채널은 40keV, 4312/cm2로, LDD는 50keV, 8e12/cm2로 이온주입하였고, 4000A의 SiOx를 증착한 후 2500A의 Side-wall을 형성하였다. 옴익 접촉은 AuGe/Ni/Au 합금을 이용하였고, 소자의 최종 Passivation은 SiNx 박막을 이용하였다. 제작된 소자의 전기적 특성은 hp4145B parameter analyzer를 이용한 전압-전류 측정을 통하여 평가하였다. Side-wall 형성은 0.3$\mu\textrm{m}$ 이상의 패턴크기에서 수직으로 잘 형성되었고, 본 연궁에서는 게이트 길이가 0.5$\mu\textrm{m}$인 MESFET을 제작하였다. d.c. 특성 측정 결과 Vds=2.0V에서 임계전압은 -0.78V, 트랜스컨덕턴스는 354mS/mm, 그리고 포화전류는 171mA/mm로 평가되었다. 특히 본 연구에서 개발된 트랜지스터의 게이트 전압 변화에 따른 균일한 트랜스 컨덕턴스의 특성은 RF 소자로 사용할 때 마이크로 웨이브의 왜곡특성을 없애주기 때문에 균일한 신호의 전달을 가능하게 한다. 0.5$\mu\textrm{m}$$\times$100$\mu\textrm{m}$ 게이트 MESFET을 이용한 S-parameter 측정과 Curve fitting 으로부터 차단주파수 fT는 40GHz 이상으로 평가되었고, 특히 균일한 트랜스컨덕턴스의 경향과 함께 차단주파수 역시 게이트 바이어스, 즉 소오스-드레스인 전류의 변화에 따라 균일한 값을 보였다. 본 연구에서 개발된 Side-wall 공정은 게이트 길이가 0.3$\mu\textrm{m}$까지 작은 경우에도 사용가능하며, WNx self-align gate MEESFET은 낮은 소오스저항, 균일한 임계전압 특성, 그리고 높고 균일한 트랜스 컨덕턴스 특성으로 HHP(Hend-Held Phone) 및 PCS(Personal communication System)와 같은 이동 통신용 단말기의 MMICs(Monolithic Microwave Integrates Circuits)의 제작에 활용될 것으로 기대된다.

• Journal of Korean Society of Environmental Engineers
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• v.35 no.2
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• pp.101-108
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• 2013

Ara Canal is the first artificial canal in Korea that connects the Han River and the Yellow Sea. Due to mixture of waters with different salinity and water quality, complicated hydrodynamic and water quality distributions are expected to occur inside the canal. An integrated hydrodynamic and water quality modeling system was developed using the 3 dimensional hydrodynamic model, EFDC (Environmental Fluid Dynamics Code) and the water quality model WASP (Water Quality Analysis and Simulation Program). According to the modeling results, BOD, TN, TP and Chl-a concentrations inside the canal were lower at the West Gate side than the Han River side since influent concentrations of the West Gate side are significantly lower. Chemical stratification due to salinity difference were more evident at the West Gate side as vertical salinity difference were more pronounced in this area. On the other hand, Chl-a concentrations showed more pronounced vertical distribution at the Han River side as Chl-a concentrations were higher in this area. It was notable that Dissolved Oxygen concentrations can be lower than 2 mg/L occasionally in the middle part of the canal. While major factor affecting DO concentrations in the canal are inflows via both gates, the other important factor was found to be BOD decay in the canal due to extended hydraulic residence time. This study can be used to predict hydrodynamic conditions and water quality in the canal during the year and thus can be helpful in the development of gate operation method of the canal.

• 한국정보디스플레이학회:학술대회논문집
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• 2004.08a
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• pp.395-398
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• 2004

We developed an a-Si TFT-LCD panel with integrated gate driver circuit using a standard 5-MASK process. To minimize the effect of the a-Si TFT current and LC's capacitance variation with temperature, we developed a new a-Si TFT circuit structure and minimized coupling capacitance by changing vertical architecture above gate driver circuit. Integration of gate driver circuit on glass substrate enables single chip and 3-side free panel structure in a-Si TFT-LCD of QVGA(240$^{\ast}$320) resolution. And using double ASG structure the dead space of TFT-LCD panel could be further decreased.

• Journal of the Korean Vacuum Society
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• v.8 no.4B
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• pp.536-540
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• 1999

We have developed a refractory WNx self-aligned gate GaAs metal-semiconductor field-effect transistor(MESFET) using $SiO_2$ side-wall process. The MESFET hasa fully ion-implanted, planar, symmetric self-alignment structure, and it is quite suitable for integration. The uniform trans-conductance of 354nS/mm up to Vgs=+0.6V and the saturation current of 171mA/mm were obtained. As high as 43GHz of cut-off frequency hs been realized without any de-embedding of parasitic effects. The refractory WNx self-aligned gate GaAs MESFET technology is one of the most promising candidates for realizing linear power amplifier ICs and multifunction monolithic ICs for use in the digital mobile communication systems such as hand-held phone(HHP), personal communication system (PCS) and wireless local loop(WLL).

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2003.10a
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• pp.773-776
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• 2003

In this paper, we have designed the p-type SiGe MOSFET and analyzed the electrical characteristics. When the gate voltage is biased to -1.5V, the threshold voltage values are -0.97V and -1.15V at room temperature and 77K, respectively. We know that the operating characteristics of SiGe MOSFET is superior to the basic Si MOSFET which the threshold voltage is -1.36V.

• Journal of the Korean Society for Aviation and Aeronautics
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• v.12 no.2
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• pp.43-58
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• 2004

Up-to-date cargo transport system, CVO(Commercial Vehicle Operations) is the system to manage efficiently cargo distribution as providing at real time the information of cargo location and situation through ITS and GPS technology. In this paper, we proposed the Gate Automation System of harbors among AEI/AVI. To implement his system, we use the DSRC/RFID(Dedicated Short Range Communication / Radio Frequency IDentification) which adopts an wireless communication between RSE(Road-side Equipment) and OBE(on-Board Equipment) on a vehicle. When constructing the Gate automation system of harbors, the business application ability are reviewed practically and the logistics facilities to be constructed in the near future may use this project results according to the international standard and it could help complete integrated logistics system.