• 한국주조공학회지
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• 제42권6호
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• pp.358-368
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• 2022

본 연구에서는 다양한 생압고철의 충전 거동을 시각화 시뮬레이션하였고, 초기 장입 단계가 종료된 후, 충전 상태를 정량적으로 비교하였다. 300mm 정육면체 생압고철, 맞춤형 정육면체 생압고철, 맞춤형 팔각기둥 생압고철, 맞춤형 원기둥 생압고철을 비교 대상으로 하였다. 맞춤형 생압고철의 경우, 1, 1.5, 2, 3, 4, 5, 6t/h 용량의 용해로에 맞춤형 크기로 설계하였다. 초기 장입 개수, 추가 장입 중량 백분율, 충전 밀도, 틈새 공간 부피 백분율 등 충전 상태를 비교 평가하였다.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1999년도 추계학술대회 논문집
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• pp.125-128
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• 1999

(Ba$_{0.6}$Sr$_{0.4}$)TiO$_3$(BST) thin films were fabricated with different deposition temperature by Pulsed Laser Deposition(PLD). This BST thin films showed a maximum dielectric constant value of $\varepsilon$$_{r}$=~684 and dielectric loss was ~0.01 when substrate temperature was 75$0^{\circ}C$. Charge storage density of BST thin film was 4.733 [$\mu$C/$\textrm{cm}^2$] and estimated charging time was 0.15 nsec. Leakage current density of BST thin film was below 10$^{-7}$ [A/$\textrm{cm}^2$] at 3V. 3V.V.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2011년도 전력전자학술대회
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• pp.218-219
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• 2011

In this paper Li-polyer batteries, which are in use of EV recently, are used. The Li-polymer batteries have high density of energy and invulnerability of the fluids and explosion. It is confirmed that the DC-bias pulse mode/cc mode characteristics on charge by designing Fast-charging system designed in three phase PWM and full-bridge converter.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2009년도 춘계학술대회 논문집
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• pp.315-318
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• 2009

Hydrogen is the ideal candidate as an alternative energy carrier, so many hydrogen storage methods are investigated. The hydrogen storage method using metal hydride is good candidate as energy sources for portable devices because hydrogen-storage as metal hydride shows large volumetric storage density. In this study, we investigated the variations of hydrogen charging/discharging performance of metal hydride tanks at different temperature conditions. We charged metal hydride tanks with hydrogen in low temperature because of the exothermic reactions of hydrogen absorption while we discharged in high temperature to provide sufficient heat because of the endothermic reactions of desorption. In addition, we investigated the difference of hydrogen charging/discharging performance between two tanks having different sizes.

• 한국연소학회:학술대회논문집
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• 한국연소학회 2004년도 제28회 KOSCO SYMPOSIUM 논문집
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• pp.158-164
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• 2004

In the present work, the numerical model was refined to predict the thermal analysis of energy storage in a fixed beds during charging mode. The governing energy equations of both fluid and the solid particles along with their initial and boundary conditions are derived using a two-phase, one dimensional model. The refined model is carried out by taking into account change of (air density , air specific heat) with air temperature and also by taking into considerations heat losses from bed to surrounding. Finite difference method was used to obtain solution of two governing energy equations of both fluid and solid particles through a computer program especially constructed for this purpose. The temperature field for the air and the solid are obtained, also energy stored inside the bed is computed. A comparison between refined model and non refined model is done. Finally using refined model the effect of bed material (Glass, Fine clay ,and aluminum ), and air flow rate per unit area Ga (0.3, 0.4, and 0.5 kg/$m^2$-s) on energy storage characteristics was studied.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2003년도 춘계학술대회
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• pp.1499-1505
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• 2003

Rapid development of electronic technology requires small size, high density packaging and high power of electronic devices. So, in this paper, characteristics on oscillating heat pipe according to operating conditions(environment temperature, charging ratio of working fluid, inclination) based on experimental study was investigated. From the experimental results, $25^{\circ}C$environment temperature), R-141b(working fluid)40%(charging ratio) was best performace at others of inclination angle and The top heating mode of OCHP performed 80% efficiency of the bottom heating mode.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 1999년도 추계종합학술대회 논문집
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• pp.216-219
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• 1999

A simple two-terminal cyclic current-voltage(I-V) technique is used to measure the current-transients in MOS capacitors. Distinct charging/discharging currents were measured and analyzed as a function of (1) the hold time. (2) the gate polarity during the FNT electron injection, (3) the injection fluence and (4) the annealing time after the injection had stopped. Discharging and charging current-transients were strongly dependent upon the conditions for forming the inversion layer and the density of interface traps caused during the FNT electron injection, respectively. Several tentative mechanisms were suggested in the current work.

• Journal of Advanced Marine Engineering and Technology
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• 제29권4호
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• pp.436-442
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• 2005

Rapid development of electronic technology requires small size, high density packaging and high power of electronic devices. In this paper, characteristics on oscillating heat pipe according to operating conditions (environment temperature, charging ratio of working fluid, inclination) based on experimental study was investigated From the experimental results $25^{\circ}C$(environment temperature) R-141b (working fluid) $40\%$ (charging ratio) was best performace at others of inclination angle and the top heating mode of OCHP performed $80\%$ efficiency of the bottom heating mode.

• 한국정보처리학회:학술대회논문집
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• 한국정보처리학회 2023년도 추계학술발표대회
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• pp.1159-1160
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• 2023

본 논문에서는 전기차 충전소 어플리케이션 신규 기획을 위해 많은 사람들이 사용하고 있는 전기차 충전소 어플리케이션을 조사한다. 더 나아가 자사 충전소를 설치해야 차별성을 가질 수 있을 것이라고 판단하고 충전소 설치 위치를 선정하기 위해 지역별 전기차 충전소의 이용량을 분석한다. 결과적으로 총 n 개의 어플리케이션을 비교하여 전기차 앱의 트랜드와 기능의 장단점등을 분석한다. 클라우드 환경에서 오픈 API 를 활용하여 충전소 이용현황 정보를 21 년 12 월부터 22 년 1 월까지 수집하였고 통계 분석 툴인 Tableu 를 사용하여 지역별 충전율과 밀집도를 계산하여 충전소를 설치하기에 좋은 지역구 후보를 선정한다

• 대한기계학회논문집A
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• 제26권6호
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• pp.1107-1113
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• 2002

This study presents the hydrogen emblittlement in the metal, which decreases the ductility and then induces the brittle fracture. The contribution deals with the effect of strain rate and notch geometry on hydrogen emblittlement of 1.25Cr-0.5Mo and 2.25Cr-1Mo steels, which are in use at high pressure vessel. Smooth and notched specimens were examined to obtain the elongation and tensile strength. For charging the hydrogen in the metal, the cathodic electrolytic method was used. In this process, current density is maintained constant. The amount of hydrogen penetrated in the specimen was detected by the hydrogen determenator(LECO RH404) with the various charging time. The distribution of hydrogen concentration penetrated in the specimen was obtained by finite element analysis. The amount of hydrogen is high in smooth specimen and tends to concentrate in the vicinity of surface. The elongation and tensile strength decreased with the passage of charging time in 1.25Cr-0.5Mo and 2.25Cr-1Mo steels. The elongation increased and tensile strength decreased as strain rate increased. As a result of this study, it is supposed that 1.25Cr-0.5Mo steel is more sensitive than 2.25Cr-lMo steel in hydrogen embrittlement. Hydrogen embrittlement susceptibility of notched specimen after hydrogen charging is more remarkable than that of smooth specimen.