• Journal of the Semiconductor & Display Technology
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• v.6 no.1 s.18
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• pp.53-57
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• 2007

In this paper, the intelligent estimation algorithm is developed for residual quantity estimate of lithium secondary cell and we suggest the control algorithm to get battery SOC through thermal modeling of electric cell. Lithium secondary cell gives cycle life, charge characteristic, discharge characteristic, temperature characteristic, self-discharge characteristic and the capacity recovery rate etc. Therefore, we make an accurate estimate of the capacity of battery according to thermal modeling to know the capacity of electric cell that is decreased by various special quality of lithium secondary cell. And we show effectiveness through comparison of value as result that use simulation and fuzzy logic.

• Journal of Institute of Control, Robotics and Systems
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• v.13 no.1
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• pp.6-14
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• 2007

Modem version of supersonic jet fighter aircraft must have been guaranteed appropriate controllability and stability in HAoA(High Angle of Attack). Limit value of aircraft entering into the departure in HAoA is related to aircraft configuration design. But, the control law such as AoA and yaw-rate limiter is implemented in digital Fly-By-Wire flight control system of supersonic jet fighter to guarantee the aircraft's safety in HAoA. The HAoA flight control law have two parts, one is control law of departure prevention and the other is control law of departure recovery support. The control laws of departure prevention for advanced jet trainer consist AoA limiter, roll command limiter and rudder fader. The control laws of departure recovery support are consist yaw-rate limiter and MPO(Manual Pitch Override) mode. The guideline of pitch rocking using MPO mode is simple, but operating skill of pitch rocking is very difficult by the pilot with inexperience of departure situation. This paper addresses the design and validation of APR(Automatic Pitch Rocker) control law instead of MPO in order to automatic recovery without manual pitch rocking by the pilot. And, recovery characteristic with APR verifies by the nonlinear analysis and pilot evaluation.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.23 no.5
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• pp.640-645
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• 2012

DC-DC converter and DC-AC inverter in a hybrid electric vehicle (HEV) generate the switching noise. It may be generated by the reverse recovery operation of the power diode in the switching circuit of the converter or the inverter. The shape of the reverse recovery region may be determined by both reverse time and recovery time in the diode. So, in this paper, the frequency spectrum of switching noise was estimated by the shape of the reverse recovery region and compared with the measured results. It shows that the meaningful region of the frequency spectrum is directly related with the reverse time.

• The Journal of Korean Medicine
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• v.27 no.4
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• pp.116-124
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• 2006

Peripheral nerve injuries are a commonly encountered clinical problem and often result in chronic pain and severe functional deficits. At the Dept. of Oriental Rehab. Medicine, we have used for pain control a herbal bath containing the following herbs: Harpagophytum radix, Atractylodes japonica and Corydalis tuber. In the present study, we investigated the effects of this herbal bath on the recovery rate of the locomotor function and the expression of c-Fos in the ventrolateral periaqueductal gray (vIPAG) region of the brain following sciatic crushed nerve injury in rats. In the present study, characteristic gait change with decreasing of the sciatic function index (SFI) was observed and c-Fos expression in the vIPAG was suppressed following sciatic crushed nerve injury in rats. Immersion into herbal bath enhanced SFI value and restored c-Fos expression in the vIPAG to the control value. These results suggest the herbal bath might activate neurons in the vIPAG, and could facilitate functional recovery from peripheral nerve injury.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2006.11a
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• pp.221-221
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• 2006

The SMD type P-N junction diode with ceramic package for diode case were fabricated. It was made this diode with simple process from $Al_2O_3$ ceramic chip, solder preform, diode chip, coating reagent and conductive paste for chip terrmination. Its merit is small size, easy manufacture. fast cooling with ceramic case. The electric characteristics of the diode such as reverse recovery time, breakdown voltage, forward voltage, and leakage current were 5 28ns, 1322V, 1.08V, $0.45{\mu}A$.

• Journal of Electrical Engineering and Technology
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• v.10 no.3
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• pp.1066-1074
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• 2015

This paper presents the reverse recovery characteristic according to the change of switching states when Si diode and SiC diode are used as clamp diode and proposes a method to minimize the switching loss containing the reverse recovery loss in the neutral-point-clamped inverter at low modulation index. The previous papers introduce many multiple circuits replacing Si diode with SiC diode to reduce the switching loss. In the neutral-point-clamped inverter, the switching loss can be also reduced by replacing device in the clamp diode. However, the switching loss in IGBT is large and the reduced switching loss cannot be still neglected. It is expected that the reverse recovery effect can be infrequent and the switching loss can be considerably reduced by the proposed method. Therefore, it is also possible to operate the inverter at the higher frequency with the better system efficiency and reduce the volume, weight and cost of filters and heatsink. The effectiveness of the proposed method is verified by numerical analysis and experiment results.

• Journal of the Society of Naval Architects of Korea
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• v.53 no.3
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• pp.195-200
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• 2016

In this study, compression tests for the polyisocyanurate foam which is recognized as the insulation material for the storage tank of the liquefied natural gas (LNG) were carried out for investigation of the material characteristic of mechanical behavior. Deformation recovery ratio according to the various initial deformation levels were estimated and the mechanical behavior of foams that are experienced compressive deformation was also obtained experimentally. The test results were analyzed based on the conditions of initially applied strain level and engineering strain rate.

• Proceedings of the KIEE Conference
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• 1999.07d
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• pp.1605-1607
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• 1999

Silicone rubber have presently been using in large number for a variety of outdoor HV applications. Silicone rubber have the properties of low surface energy and are able to retain its hydrophobicity or water repellency, thereby suppress the leakage current in the present of moisture and contamination. In this paper, we investigated the recovery characteristics of silicone rubber by measuring the leakage current under salt-fog.

• Journal of the Korean Society of Visualization
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• v.15 no.3
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• pp.47-51
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• 2017

In this study, we investigate the wake characteristics in laminar inflow and two different turbulent inflow cases. To solve the flow with wind turbines and its wake, we use large eddy simulation (LES) technique with actuator line method (ALM) and turbulent inflow of Turbsim. We perform the quantitative analysis of velocity deficit and turbulent intensity in laminar inflow case and turbulent inflow case with different turbulent intensity. In turbulent inflow, unsteady strong wake recovery which is highly fluctuated in time. Normalized power in turbulent inflow case is also highly fluctuated with unsteady wake recovery, while that in laminar inflow has quasi steady characteristic in power generation.

• Journal of computational fluids engineering
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• v.15 no.1
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• pp.17-23
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• 2010

Performance improvements of the heat recovery steam generator(HRSG) can be achieved by improving the flow distribution of exhaust gases for a various type of different equipments. A number of design parameters are systematically investigated and their effects on an index of velocity deviation established. The parameters include the three shape of the transition duct and the wide range of the guide vane angles. The numerical results clearly reveal feature of the flow pattern in the transition duct, velocity deviation and pressure drop at tube bank part.