• Journal of Power Electronics
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• v.14 no.1
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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.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 2004.05a
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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.

• Korean System Dynamics Review
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• v.8 no.2
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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.

• Korean System Dynamics Review
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• v.9 no.2
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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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• v.17 no.1
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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.

• The Journal of the Korea Contents Association
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• v.20 no.5
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• pp.90-104
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• 2020

The current global economy is changing from a proprietary commercial economy to a shared economy of value sharing. In modern society, single-person households have become common type of households. The reason for the increase in single-person households is due to the rising age of first marriage, the increasing number of elderly people, which is a result of the extension of the average life expectancy, fewer marriages, more divorces, goose fathers, the separation between dwellings for work, etc. Especially a significant amount of single-person households is occupied by young people, which is common in large cities. Along with the increase in the number of single-person households, the youth has created a new demand for housing demand for single-person households. The purpose of this study is to identify which factors influence the preference of a share house as an alternative to a single-person household by making an empirical analysis. As a result of the analysis, the accessibility of a share house, the characteristics of the building and the facilities all had a significant effect on the preference.

• Proceedings of the KIEE Conference
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• 2003.04a
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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.

• Proceedings of the KIPE Conference
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• 2003.07b
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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.

• Korea Journal of Hospital Management
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• no.spc
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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.

• Research in Mathematical Education
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• v.22 no.2
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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.