• 대한기계학회논문집
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• 제14권3호
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• pp.656-663
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• 1990

본 연구에서는 이러한 해석적 근사해를 이용한 스터링기관의 최적설계조건에 관하여 취급하고자 한다. 단열해석의 결과를 대응하는 등온해석과 비교, 고찰함으로 써 방법에 따른 조건의 차이를 보이고 주요 설계인자의 성능에 미치는 영향을 규명한 다. 또한, 제인자에 따른 기관성능의 변화추이가 편리하게 표시될 수 이씨는 일종의 성능선도(performance map)를 작성하고자 한다.

• 한국인터넷방송통신학회논문지
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• 제10권3호
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• pp.179-184
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• 2010

본 논문에서, 실내 다중 경로 무선 채널에서 초광대역(UWB: ultra wide band) 시스템을 위한 레이크 수신기의 성능을 분석한다. 펄스 위치-시간 도약(PPM-TH: pulse position modulation-time hopping) 신호가 고려되었다. 그리고 또한 이상적인 레이크, 선택적 레이크, 부분적 레이크 수신기 등의 세 종류의 레이크 수신기를 고려한다. 실내 채널은 IEEE 802.15.SG3a에서 UWB 채널 모델로 제안한 수정된 SV (Saleh and Valenzuela) 모델로 모델링하였다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2003년도 학술회의 논문집 정보 및 제어부문 B
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• pp.818-822
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• 2003

We propose a software-reliability growth model incoporating the amount of uniform and Weibull testing efforts during the software testing phase in this paper. The time-dependent behavior of testing effort is described by uniform and Weibull curves. Assuming that the error detection rate to the amount of testing effort spent during the testing phase is proportional to the current error content, the model is formulated by a nonhomogeneous Poisson process. Using this model the method of data analysis for software reliability measurement is developed. The optimum release time is determined by considering how the initial reliability R(x|0) would be. The conditions are $R(x|0)>R_o$, $R_o>R(x|0)>R_o^d$ and $R(x|0)<R_o^d$ for uniform testing efforts. Ideal case is $R_o>R(x|0)>R_o^d$. Likewise, it is $R(x|0){\geq}R_o$, $R_o>R(x|0)>R_o^{\frac{1}{g}$ and $R(x\mid0)<R_o^{\frac{1}{g}}$ for Weibull testing efforts. Ideal case is $R_o>R(x|0)>R_o^{\frac{1}{g}}$.

• 수산경영론집
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• 제54권2호
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• pp.31-44
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• 2023

This study examines the demand system of shrimp imported from top four countries and domestically produced by using AIDS (Almost Ideal Demand System) model. Top four import countries are Vietnam, Ecuador, China, and Malaysia based on the value of imports in 2021. As results of the analysis, the demand system of shrimp turn out to be below. First, the relationship of domestic shrimp and imported shrimp (Ecuadorian and Vietnamese) is identified as complements or substitutes depending on whether the income effect is considered. This result implies that imported shrimp supplements domestic supply against excess demand while homogeneous shrimp products competes with domestic shrimp in fish market. Second, the relationship among imported shrimps turned out to be both substitutes and complements. Especially, the Vietnamese shrimp is complementary with Chinese and Malaysian shrimp, but substitutes of Ecuadorian. It is assumed that adjoining Asian countries shares similar shrimp species and processing system which differentiates from Ecuadorian. Finally, the study included quarter as dummy variable and GDP as instrumental variable of expenditure in the model. The result confirmed that domestic shrimp is highly on demand during the main production season while imported shrimp is mainly demanded during the rest of the season.

• 전력전자학회:학술대회논문집
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• 전력전자학회 1996년도 창립기념 전력전자학술발표회 논문집
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• pp.89-92
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• 1996

This paper describes a detailed simulation model of the static condenser (STATCON) to analyze the dynamic interaction with the ac transmission line. The static condenser was represented by a 12-pulse voltage-source inverter sharing an energy storage dc capacitor. The voltage-source inverter consists of two 6-pulse bridges modeled with ideal gate-turn-off switches. The control system for the static condenser was designed through a mathematical model deduced from the equivalent circuit. Simulation results show that the conceived model is very effective to analyze the dynamic interaction between the static condenser and the ac transmission system.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2002년도 추계학술대회 논문집 전기기기 및 에너지변환시스템부문
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• pp.313-316
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• 2002

In this paper, we present an online scheme for parameter estimation of solar cell, based on the model adjustment technique and a genetic algorithm. The ideal diode model and the diode model with series and shunt resistor are used to estimate their parameters. Simulation works using field data in the form of a VI characteristic curve are carried out to demonstrate the effectiveness of the proposed method.

• 한국막학회:학술대회논문집
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• 한국막학회 2004년도 Proceedings of the second conference of aseanian membrane society
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• pp.152-154
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• 2004

A new model of selectively preferential sorption-facilitated transport with fixed site carriers was advanced in this paper. A number of experiments were arranged to demonstrate the ideal above. Preliminary results were obtained from the experiments, and shown the model was applicable for many membrane processes, such as RO, ED, gas separation and liquid membranes etc.

• 대한공간정보학회지
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• 제3권2호
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• pp.115-130
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• 1995

최근에 들어 정부차원에서 GIS 활성화를 위한 전반적인 계획을 완성하였고 그 계획 중 가장 큰 비중을 차지하고 많은 파급효과를 가져올 국가기본도 전산화를 이미 시작하였다. 많은 예산을 들여서 만들어질 데이타가 전통적인 지도제작을 목적으로 구축되기보다는 앞으로의 많은 응용분야에서 활용할 수 있는 데이타가 입력 당시부터 고려되는 것이 바람직하기에 수치지도제작(Automated Mapping)만을 위한 데이타모델과 다양한 응용을 수용할 수 있는 데이타 모델의 차이점을 분석하고 외국 국립지리원들의 데이타 구축사양을 비교해 봄으로 국가기본도 데이타베이스의 구축모델의 방향을 제시하였다. 우리의 실정에 맞는 모델의 설정을 위해 영국의 Ordnance Survey와 미국의 USGS의 데이타 구축모델을 분석하여 이상적 모델을 제시하고, 우리나라가 최근에 선택한 데이타 진환 표준안인 SDTS와 연계시켜 효율적으로 선진국 수준에 갈 수 있는 한국형 모델을 구상하였다. 이러한 모델의 구상은 우리나라 국립지리원의 지도제작 목적과 다양한 응용을 동시에 수용하기 위한 것이며 궁극적으로 한국의 실정에 맞는 모델이 구체화되는 계속적인 연구가 있어야 할 것이다.

• 한국의류산업학회지
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• 제17권3호
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• pp.382-391
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• 2015

People are exposed to diverse images and naturally find images to express themselves to others for personalsatisfaction. They present ideal images that they desire to obtain or actual images that they already have. People find differences between ideal images and actual images as well astry to overcome differences by managing appearance or purchasing fashion items. The congruence between real and ideal self-images and perceived body images stimulate clothing involvement or consumer confidence to influence fashion innovativeness and fashion opinion leadership. Fashion leaders are known for confidence when making buying decisions on new fashion products and are more likely to influence other consumers to buy new items. This study useda structural equation model to understand the influence of perceived self and body image on clothing involvement and consumer confidence as well as define how perceived images influence fashion leadership through clothing involvement and consumer confidence. The results of this study indicated that self-image congruence has a positive impact on social body image and personal body image. A positive influence of perceived body image on clothing involvement and consumer confidence was also detected. Fashion opinion leadership could be explained by clothing involvement and consumer confidence; however, fashion innovativeness could only be explained by consumer confidence.

• Journal of Power Electronics
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• 제17권5호
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• pp.1268-1277
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• 2017

Three-phase pulse width modulation (PWM) rectifiers are usually designed under the assumption of ideal ac power supply and input inductance. However, non-ideal circuit parameters may lead to a voltage collapse of PWM rectifiers. This paper investigates the mechanism of voltage collapse in three-phase PWM rectifiers. An analytical stability boundary expression is derived by analyzing the equilibrium point of the averaging state space model, which can not only accurately locate the voltage collapse boundary in the circuit parameter domain, but also reveal the essential characteristic of the voltage collapse. Results are obtained and compared with those of the trial-error method and the Jacobian method. Based on the analysis results, the system parameters can be divided into two categories. One of these categories affects the critical point, and other affects only the instability process. Furthermore, an effective control strategy is proposed to prevent a vulnerable system from being driven into the instability region. The analysis results are verified by the experiments.