• Journal of Power Electronics
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• 제14권1호
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• pp.22-29
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• 2014

Current sharing between modules in a converter parallel operation is very important for the reliability of the system. This paper proposes an improved droop method that can effectively improve current sharing accuracy. The proposed method adaptively adjusts the output voltage set-point of each module according to the current set-points. Unlike conventional droop control, modules share a signal line to communicate with each other. Nevertheless, since signals are simple and in digital form, the complexity of the circuitry is much less and noise immunity is much better than those of conventional methods utilizing communication. The operation principle and design procedure of the proposed method are described in detail. Results of the experiment on two boost converters operating in parallel under the specification of a TFT LCD TV panel power supply verify the validity of the proposed scheme.

• 한국조명전기설비학회:학술대회논문집
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• 한국조명전기설비학회 2004년도 춘계학술대회 논문집
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• pp.437-441
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• 2004

Recently, as the power capability of satellites increase, we need to develop a new SAR(Solar Array Regulator) with much higher power capacity whenever we design a power system of a new satelite. In this case, modular design method could be a good solution for this kind of problem. But when we use a modular method in the design of the parallelled converter, it is very important to share current equally between each module connected in paralled. In this paper, we study how to design the optimum current control-loop and voltage control-loop when we apply average current-mode control method to the parallel SAR. With the design results, we make a protype of the 3-module paralleling SAR and verify its performances.

• 한국시스템다이내믹스연구
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• 제8권2호
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• pp.5-23
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• 2007

According to the system dynamics model of this study, if there is a significant network effect on vehicle operating costs, it is difficult to achieve the shift to AFV even in the long term without a policy intervention because the car market is locked in to the current structure. Network effect can be caused by an increasing return to scale in fuel supply sector as well as in maintenance service sector. It is also related to the fact that the reliability and awareness of consumers on new products increases with the growth of the market share of the new products. There are several possible policy options to break the 'locked in' structure of car market, such as subsidy on vehicle price (capital cost), subsidy on fuel (operating cost) and niche management policy. Combined policy options would be more effective than relying on a single policy option to increase the market share of AFV.

• 한국시스템다이내믹스연구
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• 제9권2호
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• pp.27-43
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• 2008

This study investigates market barriers in increasing the market share of Alternative Fuel Vehicles (AFVs). In particular, this study first conceptualizes the AFVs market model with the aid of generic system archetypes suggested by Wolstenholme. Among four generic system archetypes suggested by Wolstenholme, the market structure of AFVs can be explained by the 'relative achievement' archetype. Starting from the generic system archetype, this study extends the model boundary step by step to take account of various model assumptions necessary to simulate the model numerically. If there is a significant network effect on vehicle operating costs, it is difficult to achieve the shift to AFVs even in the long term without a policy intervention because the car market is locked into the current structure. There are several possible policy options to break the 'locked-in' structure of the car market, such as subsidies on vehicles, subsidies on fuels, and a niche management policy.

• Asia Marketing Journal
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• 제17권1호
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• pp.55-67
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• 2015

Despite the well-known predictive power of Dirichlet model on customer loyalty, deviations of share of category requirement (SCR) predicted by Dirichlet model from actual SCR have been repeatedly reported. It has been shown that these deviations can be systematically explained by some factors such as brand's market share, product positioning strategy, purchase volume and retail marketing mix strategies. Presuming that brand equity would be additional sources of these deviations, current study assesses the incremental predictive power of brand equity by using over 4,000 brand-level observations for the consumer packaged goods industry in the U.S. Our model estimations indicate that brands that exhibit higher brand equity enjoy excess loyalty, with the primary driver being volume premium, rather than price premium. Overall, our findings support the notion that idiosyncratic brand properties can explain excess behavioral loyalty, a notion that is in stark contrast with the Dirichlet view of the world: brand equity does not exist.

• 한국콘텐츠학회논문지
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• 제20권5호
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• pp.90-104
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• 2020

현대의 세계 경제는 소유 중심적인 상업경제에서 가치 공유의 공유경제로 변화하는 추세이다. 현대 사회에서 1인 가구는 일반적인 가구 유형으로 자리매김하고 있다. 1인 가구의 증가 원인은 초혼 연령 상승으로 인한 독신 인구의 증가, 평균 수명 연장으로 인한 노인 인구의 증가, 혼인 감소, 이혼 증가, 기러기 아빠, 직장으로 인한 주거지 분리 등으로 최근에는 다양한 형태의 1인 가구가 증가하고 있다. 특히 1인 가구의 상당한 비율이 청년층이 차지하고 있고 이러한 현상이 대도시에서 흔히 나타난다. 청년층의 1인 가구의 수가 증가하면서 1인 가구의 주거수요에 대한 새로운 수요가 발생하였다. 본 연구는 1인 가구 주거수요의 하나의 대안으로 셰어하우스의 선호도 영향요인에 대한 실증분석을 하여 셰어하우스 선호도에 어떠한 요인들이 영향을 미치는 가를 파악함에 그 목적이 있다. 실증분석 결과 셰어하우스 접근성, 건축물 특성, 셰어하우스 운영 특성은 모두 선호도에 유의한 영향을 미쳤다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2003년도 춘계학술대회 논문집 전기기기 및 에너지변환시스템부문
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• pp.362-364
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• 2003

Generally, photovoltaic system is composed a number of solar cells array. so, virtual implementation module for solar cell array is needed Parallel connection each module for extract the power. A desirable characteristic of a parallel supply system is that individual converters share the load current equally and stably. The current sharing(CS) can be implemented using two approaches. The first one, known as a droop method, relies on the high output impedance of each converter. and The second approach, known as active current-sharing techniques. In this paper, analyze for better control logic of parallel connecting virtual implements of solar cell at using droop method.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2003년도 춘계전력전자학술대회 논문집(2)
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• pp.692-695
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• 2003

Generally, photovoltaic system is composed with several solar cell modules. For increasing power of photovoltaic systems, serial and parallel connection needed. A Desirable characteristic of a parallel supply system is that individual converters share the load current equally and stably. The current sharing(CS) can be implemented using two approaches. The first one, known as a droop method, relies on the high output impedance of each converter. and The second approach, known as active current-sharing techniques. In this paper, using droop method at parallel connection with it's convenience and simplicity.

• 한국병원경영학회지
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• 제spc호
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• pp.14-24
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• 2016

This study is to present current research state of the art in serviscape and performance in healthcare system. Previous studies related to serviscape in healthcare sector are explored with limitations. This study conducts a content analysis with literature reviews in order to synthesize previous studies into three branch constitution dimension of the serviscape presenting the service environment. This study provides a current research state of the art and a future direction in serviscape in healthcare sector. Study results provide serviscape, customer response, satisfaction, and behavior intention in terms of healthcare settings. The patients and hospital customers as well as hospital employees should share the service experiences of the good quality in a proper service environment so that the patients and customer can satisfy and revisit the hospital.

• 한국수학교육학회지시리즈D:수학교육연구
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• 제22권2호
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• pp.135-152
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• 2019

This conceptual paper proposes a conceptualization regarding teacher candidates' experiences as learners during instructional activities implemented by teacher educators in practice-based teacher education programs. We argue that the current learning cycle framework for teacher candidates to engage in core teaching practices does not fully address teacher candidates' own learning experiences as learners. To provide a rationale for our proposal, we examine the current conceptualization of learning to enact core practices and suggest the need for integrating teacher candidates' experiences into the current conceptualization. We also draw on research on figured worlds as an effort to conceptualize teacher candidates' experiences coming from multiple figured world. We present some examples from our own mathematics methods courses to illustrate how this newly proposed framework can be used in practice and share remaining questions for future research.