• Journal of Power Electronics
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• 제12권5호
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• pp.731-738
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• 2012

A new fluorescent dummy load to replace one of the fluorescent lamps in a dual lamp type rapid-start ballast for halving the lamp power is proposed. Using a circuit composed of a fundamental compensation circuit and a harmonic filter circuit, a new fluorescent dummy load having superior characteristics than a conventional dummy load is developed. The design principle and architecture of the proposed fluorescent dummy load is explained and verified by experiments.

• 대한전기학회논문지:전력기술부문A
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• 제52권8호
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• pp.450-456
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• 2003

This paper proposes a multiple time-series model with dummy variables for one-hour ahead load forecasting. We used 11 dummy variables that were classified by day characteristics such as day of the week, holiday, and special holiday. Also, model specification and selection of input variables including dummy variables were made by test statistics such as AIC(Akaike Information Criterion) and t-test statistics of each coefficient. OLS (Ordinary Least Squares) method was used for estimation and forecasting. We found out that model specifications for each hour are not identical usually at 30％ of optimal significance level, and dummy variables reduce the forecasting error if they are classified properly. The proposed model has much more accurate estimates in forecasting with less MAPE (Mean Absolute Percentage Error).

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2009년도 춘계학술대회 논문집
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• pp.288-294
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• 2009

Various polymer electrolyte membrane fuel cell (PEMFC) startup procedures were tested to explore possible techniques for reducing performance decay and improving durability during repeated startup-shutdown cycles. The effects of applying a dummy load, which prevents cell reversal by consuming the air at the cathode, on the degradation of a membrane electrode assembly (MEA) were investigated via single cell experiments. The electrochemical results showed that application of a dummy load during the startup procedure significantly reduced the performance decay, the decrease in the electrochemically active surface area (EAS), and the increase in the charge transfer resistance ($R_{ct}$), which resulted in a dramatic improvement in durability. After 1200 startup-shutdown cycles, post-mortem analyses were carried out to investigate the degradation mechanisms via various physicochemical methods including FESEM, an on-line $CO_2$ analysis, EPMA, XRD, FETEM, SAED, FTIR. After 1200 startup-shutdown cycles, severe Pt particle sintering/agglomeration/dissolution and carbon corrosion were observed at the cathode catalyst layer when starting up a PEMFC without a dummy load, which significantly contributed to a loss of Pt surface area, and thus to cell performance degradation. However, applying a dummy load during the startup procedure remarkably mitigated such severe degradations, and should be used to increase the durability of MEAs in PEMFCs. Our results suggest that starting up PEMFCs while applying a dummy load is an effective method for mitigating performance degradation caused by reverse current under a repetition of unprotected startup cycles.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1997년도 추계학술대회 논문집 학회본부
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• pp.182-186
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• 1997

This paper presents a mathematical approach to implementing distributed optimal power flow (OPF), wherein a regional decomposition technique is adopted to parallelize the OPF. Three mathematical decomposition coordination methods are introduced firs to implement the proposed distributed scheme: the Auxiliary Problem Principle (APP), the Predictor-Corrector Proximal Multiplier Method (PCPM), and the Alternating Direction Method (ADM). Then two alternative schemes for modeling distributed OPF are introduced; the Dummy Generator-Dummy Generator (DGDG) scheme and Dummy Generator-Dummy Load (DGDL) scheme. We present the mathematical analyses of the proposed approach, and demonstrate the approach on several test, systems, including IEEE Reliability Test Systems and parts of the ERCOT (Electric Reliability Council of Texas) system.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2001년도 추계학술대회 논문집 전력기술부문
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• pp.272-274
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• 2001

This paper presents a model for short-term load forecasting using relationship of temperature and load. We made one-day ahead load forecasting model using hourly normalized load and 11 dummy variables that were classified by day characteristics such as day of the week, holiday, and special holiday.

• 한국군사과학기술학회지
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• 제12권3호
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• pp.282-289
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• 2009

This paper presents an estimation technique of the equivalent circuit parameters for an underwater acoustic piezoelectric transducer from the measured impedance. Estimated equivalent circuit can be used for the design of the impedance matching network of the sonar transmitter. A fitness function is proposed to minimize the error between the calculated impedance of the equivalent circuit and the measured impedance of the transducer. The equivalent circuit parameters are estimated by using the fitness function and the PSO(Particle Swarm Optimization) algorithm. The effectiveness of the proposed method is verified by the applications to a sandwich-type transducer and a dummy load. In addition, the impedance matching network is also designed by using the estimated equivalent circuit model.

• 한국자동차공학회논문집
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• 제23권4호
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• pp.420-427
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• 2015

This paper statistically reviewed for the USNCAP frontal crash test results carried out by NHTSA. Vehicle samples were selected on total 20 vehicles which were included on 15 vehicles for MPV&SUV and 5 Pickup. The results was summarized as followings. The performance for the driver was better than the passenger's in the average sense. There exist distinctions between the driver and the passenger on the USNCAP front test procedure, for example dummy size, seating position and airbag style. Therefore these differences originated in the statistical results. Main effect was Neck injury for crash performance on both dummies on the average value. Root cause of neck injury was different for each dummy, ie, the driver caused from Nte & Ntf, but the passenger did absolutely Nte mode. Reliability evaluated from the standard deviation was highly dependent upon chest injury on the driver and neck injury on the passenger. Restraint system was also summarized.

• 한국자동차공학회논문집
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• 제20권5호
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• pp.81-87
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• 2012

New car assessment program (NCAP) originated from USNCAP in 1979 has been implemented in several countries or markets, for instance USA, Europe, Korea, Japan, China and Australia. NCAP has contributed greatly to reduce accidental tolls. But recently, NCAP performance has no distinction between cars because manufacturer have been continuously developed to improve NCAP performance. Therefore, NHTSA announced new USNCAP protocol becoming effective from MY2011. NHTSA had carried out many NCAP tests based on the new test protocol and announced these test results. In this paper, USNCAP test results were reviewed by statistical method. This review was focused on passenger cars and frontal crash test results in order to investigate effect of changes in new NCAP protocol. There are two key changes, one is sited female dummy in passenger position, the other is enlarged to 4 scoring body regions in each dummy. Results of this review were summarized as followings. Performance in Passenger (12.5%) is lower than Driver's (50%) for number of 5 star vehicle. Neck injury criterion is dominant to NCAP star rating for both dummies in the mean sense. For standard deviation, chest deflection is showed largest value in driver dummy but neck injury criterion is showed for passenger's. DKAB and PKAB were equipped 28.1% and 6.2%, respectively. Consequently, the countermeasure for new USNCAP frontal crash test is essential to control well dummy kinematics with some safety features including KAB to reduce neck injuries.

• 대한기계학회논문집A
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• 제35권10호
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• pp.1187-1191
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• 2011

이 응용논문에는 적응형 로드리미터에 대해 기술되어 있다. 적응형 로드리미터는 안전벨트의 구성품 중 하나이며, 이는 승객의 다양한 체중과 키에 따라 하중량을 고하중과 저하중으로 변환시킬 수 있는 장치이다. 최근, FMVSS 208규정은 다양한 더미크기에 대해 엄격한 안전기준을 요구하고 있다. 이에 따라 우리는 고하중 조건과 저하중 조건 시 각각 더미에 흉부 상해정도를 알아보았고, 실험을 통해서 벤치마킹모델의 하중조건을 확인하였다. 이를 토대로 적응형 듀얼레벨 로드리미터를 개발하여 성능 실험을 실시하였고, 유한요소해석을 통해 설계 개선점을 확인하였다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1993년도 하계학술대회 논문집 A
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• pp.42-44
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• 1993

As for the organization of actual test facilities, we carried out the conceptual design for the actual test facilities related to PAFC simulater, PCS, distribution feeder, dummy load, measurement system and fault generation equipment.