• KIEE International Transactions on Power Engineering
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• v.3A no.3
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• pp.168-176
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• 2003

The Korea Electric Power Corporation (KEPCO) has installed an 80 MY A Unified Power Flow Controller (UPFC) at its 154㎸ 'Kang-Jin Substation in South Korea. The device, manufactured by Siemens & Hyusung, has been operational since October 2002. The Korea Electric Power Research Institute (KEPRI), a division of KEPCO was tasked to study operational strategies that could be employed for the UPFC and surrounding reactive support devices concerning problems of low voltages and overloads in the Mokpo & Gwangju areas. Particular apprehension surrounded the possibility of delay in the installation of a new 345㎸ transmission line from 2005 to beyond 2010. The studies were to specifically determine whether these problems could be eliminated by application of a UPFC. The analysis included determining the UPFC operating point under various conditions, investigations of the coordination between the UPFC and a HYDC line terminating in this area, and the design of a supplementary damping controller for the UFPC. This paper summarizes the results of those studies, demonstrating the dynamic characteristics of the operation of this UPFC operation in the Korean power system.

• Journal of Korean Dental Science
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• v.2 no.2
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• pp.18-23
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• 2009

Introduction : The purposes of this study were to analyze the differences between the anterior and posterior overjets using bracket slot points, and compare two methods of overjet calculation according to different reference points using clinical bracket points on three-dimensional digital models. Methods : A total of 35 normal occlusion models were scanned using a three-dimensional scanner (Orapix$^{(R)}$, Orapix Co., Ltd, Seoul, Korea) and then, virtual brackets (0.022" Slot MBT preadjusted brackets, 3 M Co.CA. USA) were placed on the digital models using virtual setup program (3Txer$^{(R)}$ ver. 1.9.6, Orapix co., Ltd). Archwire-like curves were designed to analyze labial and buccal overjet. Results : There were no statistically significance differences between the right and left overjet and between genders. The average overjet was found to be $1.67{\pm}0.85mm$ at the central incisor area, $2.16{\pm}0.88mm$ at the second premolar and $1.53{\pm}0.71mm$ at the first molar. Conclusion : It is recommended that overjet of individualized upper and lower arch to be 2.0mm at the anterior and posterior teeth.

• Journal of architectural history
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• v.22 no.2
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• pp.31-42
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• 2013

This study identifies the current status of hanok design process and required design information through individual survey and interview with hanok architects and builders to suggest a proposal. Current design system turns out to be a common design process not reflecting hanok's unique mechanism of production. The proposal consists of the alternative design process, 'Initial survey / Site and structural planning / Spatial layout and form / Openings, interior and exterior elements design / Detail design', containing the specialty of hanok's mechanism, and the lists of design information required in its each stage. The proposed design process also emphasizes the significance of consultation in a way of designing coordination, and classifies the specific contents for each consultation moments. The study is expected to contribute for architects including the group who are not specialized in hanok to improve the architectural quality by following the systematic design process. Also the design system provides a framework to organize the vast range of design information being recently developed in the technique-oriented area.

• The Journal of Fisheries Business Administration
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• v.17 no.1
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• pp.41-76
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• 1986

The northeastern Pacific and eastern Bering Sea supports large and divers finfish and shellfish compelxes. The North Pacific fishing grounds are largest fish production total 30.89 percent of the world in 1983. Recent action by the around countries extending their fisheies jurisdiction to 200 mile has provided a new environment. The new approch to fisheries management has resulted in an arormous expansion in tile demand for scientific information. These are no longer limited to biological concerns. Emphasis has been focused recently on the need to understand the economic, social, politics and philosophy characteristics of a fishing and how they will be affected by management decisions. The horizontal management and portfolio management for fisheries has increased interest in complex biological models and the coupling of these models with economic, politics and phyisophy components. Successful completion of this task will require and expanded understanding of oceanographic, biological, economic, social, politics and philosophic process associated with fisheries. Particular attention should be devoted to acquiring information an data processing for Korean trawl fishery, stock assessment in the areas. The need for international collaboration in management must be stressed. Some northeast Pacific and eastern Bering Sea fish stock migrate over long distances and political boundaries. Further, nearly all the fish stocks are harvested by several nations. The features require cooperation and coordination of research activities. The horizontal management will be made a way these activities for the around countries in the sea. Strongly, tile proposed again, Pacific International Council for Exploration of the Seas, PICES will interest between all users of the area's fisheries.

• Journal of the Korea Fashion and Costume Design Association
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• v.20 no.1
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• pp.79-91
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• 2018

The objective of this study was to determine the influence of women's attitudes toward women's underwear on image-creation efficacy and appearance management attitude. A total of 405 surveys of women working at an industrial complex in the Daegu-Kyoungbuk area were used for data analysis. Frequency, factor analysis, reliability analysis, and regression analysis were used for data analysis. The findings were as follows. The sub-factors of women's attitudes regarding women's underwear were found to be 'aesthetics/body-style compensation', 'ostentation', 'functionality', and 'manner estimation' and the sub-factors of image-making efficacy were 'display confidence', 'face-image confidence' and 'display ability'. Appearance management attitude had factors such as total coordination, weight management, skin management, and pursuit of change. Aesthetics/body-style compensation, functionality, and ostentation, which were sub-variables of attitudes toward underwear, had a significant influence on image-creation efficacy. Aesthetics/body-style compensation and ostentation had significant influences on appearance management attitude. Aesthetics/body-style compensation was found to have a significant influence on all sub-variables of both image-creation efficacy and appearance management attitude.

• Journal of Electrical Engineering and Technology
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• v.12 no.2
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• pp.601-611
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• 2017

This paper proposes a simultaneous control of frequency deviation and electric vehicles (EVs) battery state of charge (SOC) using load frequency control (LFC) and EV controllers. In order to provide both frequency stabilization and SOC schedule near optimal performance within the whole operating regions, a multiple-input multiple-output model predictive control (MIMO-MPC) is employed for the coordination of LFC and EV controllers. The MIMO-MPC is an effective model-based prediction which calculates future control signals by an optimization of quadratic programming based on the plant model, past manipulate, measured disturbance, and control signals. By optimizing the input and output weights of the MIMO-MPC using particle swarm optimization (PSO), the optimal MIMO-MPC for simultaneous control of the LFC and EVs, is able to stabilize the frequency fluctuation and maintain the desired battery SOC at the certain time, effectively. Simulation study in a two-area interconnected power system with wind farms shows the effectiveness of the proposed MIMO-MPC over the proportional integral (PI) controller and the decentralized vehicle to grid control (DVC) controller.

• Journal of Electrical Engineering and Technology
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• v.12 no.1
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• pp.45-52
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• 2017

This paper deals with the operation strategy of reactive power in a multi-infeed HVDC (MIHVDC) system, in which several converters are connected to the same or nearby separate AC buses. The potential problems concerning a MIHVDC system when feeding a weak AC network are as follows: the need for coordination of the recovery control, the possibility of voltage instability or low quality of the area connected to the MIHVDC system, and the risk of mutual commutation failures. These problems in MIHVDC systems are similar to those in single-infeed HVDC (SIHVDC) systems, but the differences with the phenomenon of the SIHVDC system are the interactions between converters. The main reason for the potential problems of HVDC systems (MIHVDC or SIHVDC) is voltage variation; therefore, to mitigate the voltage variations, the performances of the HVDC system should be enhanced. Consequently, to mitigate the potential problems of MIHVDC systems, several solutions are suggested in this study, including installing STATCOM and installing a line arrester on the tower. The study results will be applied to a multi-infeed HVDC system in Korea.

• IE interfaces
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• v.13 no.3
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• pp.424-430
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• 2000

Supply chain management (SCM) is an area that has recently received a great deal of attention in the business community. While SCM is relatively new, the idea of coordinated planning is not. During the last decades, many researchers have investigated multi-stage inventory problems. However, only a few papers address the problem of cost-optimal coordination of multi-stage inventory control with respect to service measures. Even published approaches have a shortcoming in dealing with a delivery lead time consisted of a shipping time and a waiting time. Assumed that there is no waiting time, or that the delivery lead time is implicitly compounded of a shipping time and a waiting time, the problem is often simplified into a multi-stage buffer allocation and a single-stage stochastic buffer sizing problem at all installations. This paper presents a simulation-based heuristic algorithm and a comparison with others for the problem that cannot be decomposed into a multi-stage buffer allocation and a single-stage stochastic buffer sizing problem because the waiting time ties together all stages. The comparison shows that the simulation-based heuristic algorithm performs better than other approaches in saving average inventory cost for both Poisson and Normal demands.

• Journal of the Korean housing association
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• v.16 no.2
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• pp.91-98
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• 2005

The purpose of this study was to explore behaviors of spatial usages such as patterns of spatial usages, perception on residential spaces, and furniture arrangement. A questionnaire survey and interview were adopted in this study, and 146 residents living in apartment with 3 bedrooms, stairway access, and 3-bay style in the City of Gwangju. The major findings of this study were that 1) dining-kitchen (DK) was conceived and used as a space not only for dining but also family gathering and guest reception. Dining table without refrigerator was frequently found in furniture arrangement of DK, and refrigerator has been relocated in utility room facing DK. The results imply the need for social interaction that has been growing. Anbang (master bedroom) has been perceived and used as couples' private area, aside from the traditional function of family interaction. A coordination of both bed and wardrobe out of different furniture arrangements was popular in anbang. Living room was used as a multi-purpose room carrying out various activities such as family gathering, guest reception, and housekeeping. Sofa and cabinet were the most common furniture arrangement in living room. The research results are a basis for development residential open housing system.

• Journal of the Korean Institute of Rural Architecture
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• v.20 no.3
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• pp.27-35
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• 2018

This study investigated the public use of Myeon Location in Jeollanam - do where the population is at risk of declining. And discussed the rational provision and coordination of public facilities as a guarantee of fundamental rights. As a result of the study, the rational supply and adjustment directions of public facilities are as follows. First, there are problems such as high availability of management, finance, shopping, and health facilities, lack of culture, leisure, community facilities, and weakening of center function. Therefore, in the continuing declining population situation, face management, safety and health facilities should be upgraded to multifunctional facilities, and utilization efficiency and integration should be promoted. In addition, town center rehabilitation should be centered on multifunctional facilities. In addition, elementary schools will have to utilize and preserve them to take advantage of local cultural values as nostalgia storing place that provide incentives for young people and elementary school children in the future. Second, in order to cope with population decline, public facilities need to strengthen public services through complexity and multifunctionality, wide-area operation with neighboring areas, and user-centered operation management.