• 대한전기학회:학술대회논문집
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• 대한전기학회 2005년도 제36회 하계학술대회 논문집 B
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• pp.1483-1485
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• 2005

In recent years, customers and power supplies are interested in power quality. Demands of customers are change from standard quality of distribution power system to various high quality of distribution power system. so, it is necessary to apply power quality compensator. in our project, we develop the UPQC(Unfied Power Quality Compensator of 45kVA which compensates power factor and voltage sag, interruption. it is very frequently occurred power quality problems. As a series and shunt compensator, UPQC consists of two inverters with common dc link capacitor bank. It compensates the current quality in the shunt part and the voltage quality in the series part. In this paper, we present simulation and test result of developed UPQC system. Test for UPQC are performed at voltage sag, flickers and non-linear load conditions. For voltage sag and ficker generation, we use RTDS(Real Time Digital Simulator) and power amplifier system.

• 한국정보통신학회논문지
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• 제25권11호
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• pp.1531-1537
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• 2021

게임의 품질은 재미와 기능의 안정성으로 평가될 수 있다. 이 가운데 재미에 대한 품질 영역은 게임의 본질이므로 게임 디자이너의 입장에서는 아주 중요하게 고려해야 될 요소이다. 독창성과 몰입성이 높은 재미있는 게임 디자인은 대개 아이디어 도출, 컨셉 설정과 같은 개발 초기 단계에서 이루어진다. 이 때 게임의 재미요소 검증이 가능하도록 하는 것은 게임의 성공에 중요한 영향을 미친다. 본 연구에서는 게임 디자인 공부를 시작하는 학생들에게 재미요소 설계를 교육할 때 PIT기법을 활용한 사례를 소개하고 그 효과를 분석하였다. 고품질의 재미있는 게임 디자인을 위해 PIT기법이 게임 디자인 교육현장에서 더 활발하게 사용되기를 기대한다.

• 한국환경과학회지
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• 제14권2호
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• pp.251-258
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• 2005

Statistical analysis between operating parameters and effluent quality on advanced wastewater treatment plant was performed. Through factor analysis four factors derived varimax rotation were selected each plant. Four components explained $80\%,\;82\%$ of the total variance of the process, respectively. The components on MLE plant were identified in the following order: 1) HRT increase and BOD load decrease by influent decrease, 2) Biomass, 3) SVI increase by internal return increase, 4) Microbial diversity by SRT increase. On $A_2O$ plant, we defined them as follows: factor 1, high MLSS by return rate increase, HRT increase by influent decrease; factor 2, biomass; factor 3, BOD of influent; factor 4 was relate to DO.

• 한국정보통신설비학회:학술대회논문집
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• 한국정보통신설비학회 2008년도 정보통신설비 학술대회
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• pp.257-261
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• 2008

The Digital Radio Mondiale (DRM) system is a digital broadcasting standard designed for use in the LF, MF and HF bands of the broadcasting bands below 30 MHz. The system provides both superior audio quality and improved user services / operability compared with existing AM transmissions. In this paper, we propose a variable point Prime Factor FFT design method for Digital Radio Mondiale (DRM) system. Proposed method processes a various size IFFT/FFT of Robustness Mode on DRM standard efficiently by composing Radix-Prime Factor FFT Processing Unit of form similar to Radix-4 by insertion of a variable Prime Factor Twiddle Factor and Garbage data. So, we improved limitation that cannot process 112/176/256/288 FFT of each mode of DRM system with a existent Radix Processor and increase memory size and memory access time for IFFT/FFT processing by software processing in case of implementation with a existent high speed DSP.

• Restorative Dentistry and Endodontics
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• 제30권6호
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• pp.450-460
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• 2005

본 연구에서는 복합레진의 중합수축시 와동의 형태, 접착층의 성숙도, 및 와동의 부피가 와동저의 접착면에 발생되는 중합수축응력에 미치는 영향을 평가하였다. 1급 와동 충전시의 응력발생을 모방하기 위해, 98개의 대구치를 $2\times2\times2$ 실험군에 무작위로 분배하고 교합면 상아질을 평탄하게 연마한 후, 복합레진 충전을 위한 몰드의 역할을 할 수 있는 구멍을 가진 iris를 올려놓고 복합레진을 bulk-filling법으로 충전하였다. 각각의 변수로서 와동 형태에 관하여는 iris 재질 (접착제를 도포한 상아질 iris: 높은 C-factor, Teflon 처리된 금속 iris: 낮은 C-factor), 접착층의 성숙도에 관하여는 2종의 접착제 (Scotchbond Multi-purpose와 Xeno III), 와동의 부피에 관하여는 iris내 구멍의 직경 (직경 1 또는 $3mm{\times}높이$) 5mm)을 달리하여 전단접착강도를 측정하였다 와동의 C-factor가 클수록, 접착층의 성숙도가 우수할수록 그리고 부피가 클수록 접착력은 유의하게 감소하였다. 복합레진이 중합될 때, 와동의 형태적 제한에 따라 레진-상아질 접착계면에 발생되는 중합수축응력은 접착이 우수할수록 복합레진의 부피가 클수록 증가되므로, C-factor를 정의할 때 와동의 형태뿐 아니라, 접착층의 성숙도와 복합레진의 부피도 함께 고려되어야 된다.

• 동의신경정신과학회지
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• 제21권1호
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• pp.89-108
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• 2010

Objectives: This study was to investigate the relation of Pittsburgh Sleep Quality Index(PSQI) and Diagnos system of oriental medicine(DSOM) in the Insomnia Patients. Methods: For this study, we carried out PSQI and DSOM of 92 patients with insomnia who have come to Kijang public health center and Donguei oriental hospital of Donguei university from November 2008 to October 2009. We verified the association of PSQI and DSOM using crosstabulation analysis, independent sample T-test, one-way ANOVA and correlation analysis. Results: 1. Blood-deficiency(血虛) is the most frequent pathogenic factor and frequency of nightmare has positive correlation with that factor including heart(心) in total insomnia patients. 2. Female patients have a higher percentage of chronic insomnia than male patients. 3. As patients aged, maintaining sleep gets harder, sleep time is lessening, taking hypnotics is increasing and quality of sleep gets worse. 4. There is high frequency of chronic insomnia in 40~50 years and over 60 years old. Also, the people who are over 60 years of age tend to sleepless and urinated frequently during the middle of the night. The people with the age of 20~30 years tend to take less sleeping pills and frequency of sleeping during daytime is higher than the other age groups but the quality of sleep is quite good. 5. The patient with over 6 months of chronic insomnia tend to be older in age than the patient with less than 6 months. And the patient with chronic sleeping disorder has frequent pain and the quality of sleep is very poor. 6. The patient who took hypnotics tend to be older than hypnotics non-user and frequency of urination was relatively high. 7. The patient who visited oriental medical hospital were tend to be older and get difficult in maintaining sleep. And frequency of taking hypnotics and urinating during night were tend to be higher and the quality of sleep was poor compared with the patient who visited public health center. Conclusions: This study provides insights into the complicated relations of the associated symptom of insomnia with Diagnos system of oriental medicine. And especially this study showed apparent correlation between nightmare in insomnia patients and pathogenic factor of blood-deficiency and heart. Specific correlations and characteristics in this study could be connect develop of new questionaire of insomnia.

• 전력전자학회논문지
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• 제2권3호
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• pp.26-36
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• 1997

본 논문에서는 저용량의 응용 분야에 적합한 half-bridge 컨버터를 기반으로 하는 단상 AC/DC 컨버터를 제안한다. 제안된 컨버터는 고역률, 저하모닉 왜곡의 특성이 있으며 좋은 출력 레귤레이션 특성을 가지고 있다. 그리고 asymmetrical 제어를 통해 소프트 스위칭을 함으로써 스위칭 손실을 줄였으며 출력단의 정류손실을 줄이기 위해서 synchronous rectifier를 적용하였다. 또한 본 컨버터를 체계적으로 설계하기 위해 평균화법을 통한 모델링을 수행하여 설계식을 도출하였다. 이 설계식을 통하여 프로토타입 컨버터를 설계하여 실험한 결과 제안된 컨버터는 IEC555-2 규제를 만족하였고 정격에서 효율은 약 85%를 얻었다.

• Journal of Power Electronics
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• 제8권1호
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• pp.51-59
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• 2008

This paper addresses several issues concerning the analysis, design, modeling, simulation and development of single-phase, single-switch, power factor corrected AC-DC high frequency switching converter topologies with transformer isolation. A detailed analysis and design is presented for single-switch topologies, namely forward buck, flyback, Cuk, Sepic and Zeta buck-boost converters, with high frequency isolation for discontinuous conduction modes (DCM) of operation. With an awareness of modem design trends towards improved performance, these switching converters are designed for low power rating and low output voltage, typically 20.25W with 13.5V in DCM operation. Laboratory prototypes of the proposed single-switch converters in DCM operation are developed and test results are presented to validate the proposed design and developed model of the system.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2011년도 추계 학술논문 발표대회
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• pp.15-16
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• 2011

Construction automation and robotics are being taken notice as an alternative to improve productivity and quality. Reflecting on these purpose, automation system, called RCA(Robotic-crane based Construction Automation) system, is developed and have been verified through a pilot project recently in Korea. To apply the RCA system in high-rise building effectively, each management factors of element technologies in the system is derived and assessed critical factor. The purpose of this study, management factors of element techniques, consisted of RCA system, is classified through questionnaires/interviews targeting system developers and construction managers in pilot project site, and critical factors is selected using AHP.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2002년도 춘계학술대회 논문집 초전도 자성체
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• pp.7-10
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• 2002

We designed the flyback planar transformer, which had 8W capacity, with 70V input voltage and 8.2V output voltage for the establishment of design method and the confirmation of application possibility. The numerical value of inductance measured under the switching frequency of 120 kHz was 1650 ${\mu}H$, which was the inductance efficiency of 85~87% against theoretical value. The A.C. resistance of primary and secondary coil was 4.2 ${\Omega}$ and 0.25 ${\Omega}$ respectively. On the other hand, the quality factor for each wound numbers showed quite a high value of 158 and 75 respectively. And the Coupling Factor was 0.96~0.97 under 120 kHz switching frequency. And the shape of the output wave of the planar transformer at 70V input voltage was a stable square wave.