• 한국농공학회:학술대회논문집
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• 한국농공학회 2005년도 학술발표논문집
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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.

• 한국수소및신에너지학회논문집
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• 제10권1호
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• pp.49-57
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• 1999

In order to study the effect of high energy ball milling on the $Mg_2Ni+Ni$, $Mg_2Ni+0.5Ni+0.5Al$ powders, we have investigated on the discharge properties, microstructures. The powder size of samples decreased as ball milling time. From the XRD results, the crystal structure of $Mg_2Ni+Ni$ mixed powders were changed to amorphous or nano-structure after 60hr ball milling. The discharge capacities of both $Mg_2Ni+Ni$ and $Mg_2Ni+0.5Ni+0.5Al$ powders increased, with increasing ballmilling time, the maximum capacity(342mAh/g) was shown for the 60 hrs ballmilled $Mg_2Ni+Ni$ sample. The capacity decreased drastically after a few charge-discharge cycles.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1995년도 추계학술대회 논문집
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• pp.340-342
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• 1995

We prepared $LiCo_{1-x}Ni_{x}O_2$ by reacting stoichiometric mixture of LiOH.$H_2O$, $CoCO_3$.$xH_2O$ and $Ni(OH)_2$(mole ratio respectively) and heating at $850^{\circ}C$ for 5n. In the result of X-ray diffraction analysis, along fluctuation of the function of x in $LiCo_{1-x}Ni_{x}O_2$(003) peak and (104) peak indensities and ratio were varied. We awared through XRD that from 0 to 0.5 at x in $LiCo_{1-x}Ni_{x}O_2$ is well formed for hexagonal structure at one step heat treatment($850^{\circ}C$), but if Ni involve at $LiCo_{1-x}Ni_{x}O_2$ hexagonal structure is not well formed. In the result of charge/discharge tests charge/discharge capacity and effiency is different about various cathode. Therefore, the appropriate charge/discharge method must be selected for good characteristics.

• 대한전자공학회논문지SD
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• 제39권12호
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• pp.1055-1061
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• 2002

기존 TSPC D 플립플롭은 한 종류의 클럭 신호만을 사용함으로서 고속 동작을 제한하던 레이싱 (racing) 문제를 제거하고, 구조 자체도 매우 간단하기 때문에 고속 동작이 용이한 장점을 가지고 있다. 또한 한 종류의 클럭을 사용하기 때문에 클럭 드라이버 및 클럭 네트워크가 간단해 진다는 장점이 있다. 하지만 이러한 구조는 글리치나 비대칭적인 전파 지연 시간과 같은 단점을 가지고 있다. 본 논문에서는 이러한 단점을 개선한 새로운 동적 플립플롭을 설계하였다. 제안된 구조는 출력의 불필요한 방전을 막기 위한 방전 억제 방식(Discharge Suppression Scheme)을 이용하여 출력의 글리치 현상을 완전히 제거하였으며, 최대 클럭 경사 민감도를 0.25ns에서 1ns로 4배 이상 향상시킬 수 있었다. 또한 기존 구조를 개선하여 트랜지스터 수를 줄(기고, 비대칭적인 전파 지연 시간을 대칭적으로 만들어 줌으로서 기존 구조에 비해서 약 30%의 속도 향상 효과를 얻을 수 있었다.

• 한국정밀공학회지
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• 제33권12호
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• pp.965-970
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• 2016

Fuel used in the steel metallurgy industry is stored in huge stage systems called SILO. Fuel is released by RDM (Rotary Discharge Machine), at the place of utilization. RDM is located in the Silo, and is constituted of a main frame, driving part, discharging part and control part. RDM is combined to a direct motion on the rail in tunnel, having a rotary motion enabled by a motor. In this paper, we calculate the theoretical discharging capacity of RDM to confirm the correlation between design element and discharging capacity of RDM. Also, through structure analysis, we confirm the vulnerable point of RDM when it discharges the storage materials. We hope to apply these results to design a more efficient RDM.

• 한국전자통신학회논문지
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• 제16권2호
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• pp.227-232
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• 2021

본 논문에서는 다이폴 형태인 기존의 부분방전 센서의 특성을 개선하고자 센서 부분을 사다리꼴 형태로 변형시킴으로써 기존의 부분방전(PD: Partial Discharge) 센서의 단점인 협대역 특성을 개선하였다. 또한 외부부착 센서용으로 사용함에 따라 외부로 부터의 전자파 신호를 원천적으로 차단시킬 수 있는 구조인 캐버티(Cavity) 구조를 적용함으로써 저자세와 설치의 편리성을 갖는 구조적인 장점을 살리는 부분방전 센서를 제안하고자 한다. 실험 결과 중심주파수 2.45GHz에서 약 70.5%의 광대역(1.59~3.32GHz) 특성이 있음을 보여, 광대역 특성을 확인할 수 있었다.

• Nuclear Engineering and Technology
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• 제54권1호
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• pp.117-129
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• 2022

The downward discharge of the molten fuel to the lower structure of the fuel assembly could increase of the pressure drop and degrade of coolability of the assembly. To analyze the phenomena, experiments for the generation of the debris bed were conducted as LOF-DT series. Based on the debris bed in the LOF-DT, pressure drop experiment was conducted with intact and blocked component. Parametric study on the pressure drop was conducted by CFD. The LOF-DT experiments were conducted for the position and porosity of the debris bed. 85% of the debris were sedimented in the lower reflector, and 15% were in the nose piece, approximately. Porosity of the debris bed were about 0.7 and 0.85 in the lower reflector and nose piece, respectively. Pressure drop increased significantly with debris bed, especially in the lower reflector. More than 120 time of the pressure drop increased in the lower reflector, while only 10% increased in the nose piece. According to the parametric study, mass of the debris was the most important for pressure drop. The lower discharge phenomena could have a significant effect to the total pressure drop of the fuel assembly, approximately 10.8 times for the base case.

• 한국전기전자재료학회논문지
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• 제15권2호
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• pp.184-189
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• 2002

Carbon nitride films were grown on Si (100) substrate by a laser-electric discharge method with/without a magnetic field assistance. The magnetic field leads to vapor plume plasma expending upon the ambient arc discharge plasma area. Influence of the magnetic field has resulted in increased of a crystallite size int he films due to bombardment (heating) of Si substrates by energetic carbon and nitrogen species generated during cyclotron motion of electrons in the discharge zone. The surface morphology of the films with a deposition time of 2 hours was studied using a scanning electron microscopy (SEM). In order to determine the structural crystalline parameters, X-ray diffraction (XRD) was used to analysis the grown films.

• Journal of Information Display
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• 제12권1호
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• pp.29-35
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• 2011

In this study, plasma display panels with three different cell volumes were prepared by changing the spaces between the vertical barrier ribs into two and three times the reference structure. The discharge gap and area of the segmented ITO electrode were the same for the three cases, and Ne.20%Xe gas was used. The luminance and luminance efficiency were measured using applied voltage variations. The time evolution and intensity distribution of the infrared, which are related to the vacuum ultraviolet, were observed via intensified, charged, coupled device, and the visible-light intensity profiles were observed using PR-900 to analyze the discharge phenomena in the discharge cell.

• 한국분말재료학회지
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• 제27권6호
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• pp.464-467
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• 2020

Nickel nanopowders are obtained by the spark discharge method, which is based on the evaporation of the electrode surface under the action of the discharge current, followed by vapor condensation and the formation of nanoparticles. Nickel electrodes with a purity of 99.99% are used to synthesize the nickel nanoparticles in the setup. Nitrogen is used as the carrier gas with a purity of 99.998%. XRD, TEM, and EDX analyses of the nanopowders are performed. Moreover, HRTEM images with measured interplanar spacings are obtained. In the nickel nanopowder samples, a phase of approximately 90 wt% with an expanded crystal lattice of 6.5% on average is found. The results indicate an unusual process of nickel nanoparticle formation when the spark discharge method is employed.