• KSII Transactions on Internet and Information Systems (TIIS)
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• 제15권1호
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• pp.216-239
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• 2021

The present work addresses the challenging problem of coordinating power allocation with interference management in multi-robot networks by applying the promising expansion capabilities of multiple-input multiple-output (MIMO) and full duplex systems, which achieves it for maximizing the throughput of networks under the impacts of Doppler frequency shifts and external jamming. The proposed power allocation with interference coordination formulation accounts for three types of the interference, including cross-tier, co-tier, and mixed-tier interference signals with cluster head nodes operating in different full-duplex modes, and their signal-to-noise-ratios are respectively derived under the impacts of Doppler frequency shifts and external jamming. In addition, various optimization algorithms, including two centralized iterative optimization algorithms and three decentralized optimization algorithms, are applied for solving the complex and non-convex combinatorial optimization problem associated with the power allocation and interference coordination. Simulation results demonstrate that the overall network throughput increases gradually to some degree with increasing numbers of MIMO antennas. In addition, increasing the number of clusters to a certain extent increases the overall network throughput, although internal interference becomes a severe problem for further increases in the number of clusters. Accordingly, applications of multi-robot networks require that a balance should be preserved between robot deployment density and communication capacity.

• 전기학회논문지
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• 제64권8호
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• pp.1168-1179
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• 2015

This paper presents voltage and frequency control methods for a stand-alone Gasa Island Microgrid in South Korea that can be fully energized by renewable energy resources such as photovoltaic systems and wind turbines. To mitigate the variations of the output of renewable energy resources and supply more reliable electricity to customers, battery energy storage systems (BESSs) are employed in the stand-alone microgrid. The coordination between BESSs and pre-existing diesel generators is an important issue to manage the microgrid more securely. This paper presents voltage and frequency control schemes considering the coordination of BESSs and DGs. The effectiveness for the operating method is validated via simulation studies.

• 패션비즈니스
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• 제12권4호
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• pp.73-87
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• 2008

The main objective of this research was to investigate the characteristics of achromatic & chromatic color coordination of contemporary female fashion by reviewing 'pre-a-porter Collections' of four collections (i. e. cities) - Paris, Milan, New York, London - from the periods of 2002 S/S to 2006/7 A/W. The data was collected by reviewing 'pre-a-porter Collections' magazine and total 677 observations were made. Statistical analysis of frequency and also qualitative interpretation of achromatic & chromatic color coordination characteristics were completed. The main findings were; (1) The achromatic & chromatic color coordination was identified as one of most used color coordination in contmeporary women's fashion collections. (2) Black and white mainly used for achromatic color, and brown used the most often, then followed by blue, red, yellow, green and the others for chromatic color in achromatic & chromatic coordination of contmeporary women's fashion collections. (3) The characteristics of achromatic & chromatic color coordination of modern women's fashion collections from 2002 S/S to 2006/07 A/W showed various images according to chromatic colors and tone variation. The combination of achromaticand brown color variations produced an intelligent and sophisticated image. The soft or light chromatic color and chromatic color combination projected soft, feminine and subtle feeling, while the combination of vivid or strong chromatic color and achromatic color projected a clean and strong feeling through contrasting tones of clear and bright colors. The chromatic color of deep or dark tone and black combination demonstrated supernatural and gloomy image. (4)In all four collections, Paris showed most use of two color coordination and then followed by Milan, N.Y, and London. N.Y showed higher rate of using achromatic & chromatic color coordination, and then followed by Paris, London and Milan.

• 한국전자파학회:학술대회논문집
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• 한국전자파학회 2005년도 종합학술발표회 논문집 Vol.15 No.1
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• pp.125-130
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• 2005

This paper suggests an efficient method of protection ratio calculation and shows some calculated results applicable to frequency coordination in microwave relay system networks, and the net filter discrimination (NFD) associated with Tx spectrum mask and overall Rx filter characteristics has been examined to obtain the adjacent channel protection ratio. The protection ratio comprises several factors such as C/N of modulation scheme, noise-to-interference ratio, multiple interference allowance, fade margins of multi-path and rain attenuation, and NFD. According to computed results for 6.7 GHz, 64-QAM, and 60 km at BER $10^{-6}$, fade margin and co-channel protection ratio are 41.1 and 75.2 dB, respectively, In addition, NFD for channel bandwidth of 40 MHz reveals 28.9 dB at the first adjacent channel, which results in adjacent channel protection ratio of 46.3 dB. The proposed method provides some merits of an easy calculation, systematic extension, and applying the same concept to frequency coordination in millimeter wave relay system networks.

• 한국의상디자인학회지
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• 제15권2호
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• pp.109-121
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• 2013

Modern Hanbok uses newly different color coordination based on traditional color coordination and symbolic meaning. Thus, this study would investigate the aspects of color coordination and symbolic meaning and present the characteristics of Hanbok as the data of corresponding period in the modern times. In order to investigate recent trend of preferred colors and color coordination of Hanbok, this study focused on the period of 2005~2010. When analyzing colors of Jegori(jacket), Wh, Y, B, YG, P and Gy series are shown in order. For trends for color of Chima(skirt), Pk, R, P, Gy and Bk series are shown in order. When you look into the color coordination of skirt and jacket on whole, color coordination of Pk-Wh represents the highest frequency. Color coordinations of Pk-Y, Pk-B, R-Y, R-G and Pk-G are followed in order. Color coordinations of R-YG, Bk-Wh, O-Y, P-Wh, Pk-YG, Gy-Y, R-Wh series and Gy-Wh are followed in order. When looking into characteristics of overall color coordination of Hanbok, it was shown that there were many opportunities to meet a variety of culture and various colors had emerged depending on individual taste and skin color in the modern times within the framework of basic colors of woman's 'Nokeuihongsang'(Green upper garment and red skirt) R-G, Y series, which are traditionally inherited. In addition, unlike existing traditional color coordination of five elements in the past, P, Gy and Bk series of color appeared in the skirt and Jacket. It could be affected by fashionable drama and films at that time and newly attempted colors ahead of fashion were reflected on the magazine. Therefore, it implied that it naturally gave new awareness of colors to the general public and the width of selection of colors became diverse.

• ETRI Journal
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• 제44권4호
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• pp.531-542
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• 2022

With the increasing demand for unlicensed spectrum, several regulators have been opening up the 6-GHz band for unlicensed use while ensuring compliance with the technical requirement to avoid harmful interference in the existing primary services (PSs). In this paper, we present two methodologies, a channel-based method and a frequency-based method, which are applicable to a frequency coordination system that calculates the permissible transmit power in the channels or frequencies available to a secondary service (SS). In addition, we have demonstrated that the available transmit power of an SS can be maximized by adjusting the power allocation of the assigned resource units under the condition that the channel of the SS is partially overlapped with that of the PS. Based on the analysis results, it is suggested that it would be better to utilize the two methods selectively according to the operating channel conditions of the PS and the SS.

• 한국인터넷방송통신학회논문지
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• 제17권6호
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• pp.41-49
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• 2017

본 논문에서는 도심 또는 부도심에서 고정무선시스템과 이동기지국 간의 주파수 조정을 위한 이론적 모델링 및 수치해석 결과를 제시한다. 간섭분석에 필요한 주요 변수인 시스템 특성, 전파전파 모델, 보호비, 주파수의존제거, 신호-간섭 평면의 변별각을 고찰하고, 이들에 대해 수치계산을 통해 결과를 도출한다. 최소커플링손실 방법을 기반으로 가정한 고정무선시스템과 이동기지국의 특성에 대해 도심 또는 부도심에서 높이-이득 모델, 변별각, 그리고 거리의 함수로 수신간섭전력을 계산하고, 그 결과들을 보호비로부터 유도된 최대허용간섭전력과 비교한다. 제시된 방법은 다양한 무선시스템의 주파수 조정 또는 재배치 과정에 요구되는 상호 공존 또는 양립성의 기술적 분석에 유용할 것으로 판단된다.

• 패션비즈니스
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• 제12권5호
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• pp.94-110
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• 2008

The main objective of this research was to understand the characteristics of separation color coordination of contemporary female fashion through the analysis of 'pre-a-porter Collections' of four collections (i. e. cities) - Paris, Milan, New York, London - from the periods of 2004 S/S to 2008/9 A/W. The data collection of 265 was done by reviewing 'pre-a-porter Collections' magazine and total 265 observations were made. Statistical analysis of frequency and also qualitative interpretation of separation color coordination characteristics were completed. The main findings were; (1) In separation color coordination of contemporary women's fashion collections, there were three main types of color scheme which were classified into seven detailed categories of color combination. First was the achromatic color & one chromatic separation color scheme which was classified into four categories of - black & white, black & grey, white & grey, and grey & grey - color combination. Second was the chromatic colors & one achromatic separation color scheme which classified into two categories of achromatic & chromatic color & one achromatic separation color combination, and chromatic colors & one achromatic separation color combination. Third was chromatic colors and one chromatic separation color combination. (2) The achromatic colors and one chromatic separation color scheme showed two phases of reinforcing the strong and modern image, or softening the hard and dull image of achromatic color combination. In color schemes which used more than two chromatic colors, the separation color frequently converted the tedious and monotonous fashion image, which caused by identical or similarity in color or tone harmony, into more attractive and interesting. (3) In conclusion, through the various use and coordination of various color schemes, color harmony and separation colors, the separation color coordination in contemporary female fashion has been suggested the effective way of color combination which can lead the visual pleasure and the vitality along with the unity and the harmony. This characteristics can create various images and visual diversity for fashion. The types and the use of color scheme and separation color showed different trends in four collections.

• Journal of Electrical Engineering and Technology
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• 제8권6호
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• pp.1269-1275
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• 2013

Recently, many studies have suggested that an electric vehicle (EV) is one of the means for increasing the reliability of power systems in new energy environments. EVs can make a contribution to improving reliability by providing frequency regulation in power systems in which the Vehicle-to-Grid (V2G) technology has been implemented and, if economically viable, can be helpful in increasing power system reliability. This paper presents a stochastic method for optimal coordination of charging and frequency regulation decisions for an EV aggregator using the Least Square Monte-Carlo (LSMC) with modeling of electricity price uncertainty. The LSMC can be used to assess the value of options based on electricity price uncertainty in order to simultaneously optimize the scheduling of EV charging and regulation service for the EV aggregator. The results of a numerical example show that the proposed method can significantly improve the expected profits of an EV aggregator.

• 한국의상디자인학회지
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• 제25권4호
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• pp.77-92
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• 2023

The purpose of this study is to investigate the public perception of Gorpcore through Big Aata analytics. The study was conducted based on the collection of Big Data on the word 'Gorpcore' through Textom from July 24, 2017 to March 31, 2023. As a result, 63,386 words were collected from a total of 18,879 posts, and the top 50 words were determined based on frequency of appearance. Based on the collected words, centrality measures and CONCOR algorithm were performed in Ucinet 6. The research results are as follows. 1) The frequency of appearance was high in the order of 'Gorpcore look', 'fashion', 'coordination', 'clothes', 'outdoor', 'Musinsa', 'look', 'trend', 'brand' and 'ahjussi (middle-aged old man in Korean)'. These words had high TF-IDF scores, which leads to the conclusion that these are key words that are recognized as important. 2) Network centrality shows that 'Gorpcore look', 'fashion', 'outdoor', 'coordination', 'clothes', 'trend', 'look' and 'style' have a high correlation with other words. Through this, it was found that the public thinks it is important to create a variety of fashions by styling high-performance outdoor wear and casual wear, and that they are highly interested in clothes and in brands leading the Gorpcore trend. 3) As a result of the CONCOR algorithm, four significant groups were formed. The words that appear in each group are as follows. Group 1 - 'outdoor', 'Gorp', 'Normcore', 'hiking', 'functionality', 'new', 'sports', 'casual wear', 'activity', 'generation', 'collaboration'. Group 2 - 'fashion', 'trend', 'look', 'brand', 'style', 'shoes', 'ugly', 'item', 'trend', 'product', 'Salomon', 'padded jacket', 'stylishness', 'utilization', 'Winter', 'street', 'design', 'retro', 'popular', 'styling'. Group 3 - 'Gorpcore look', 'coordination', 'Musinsa', 'windbreaker', 'recommendation', 'Arcteryx', 'pants', 'man'. Group 4 - 'clothes' 'ahjussi', 'jacket', 'launching', 'spring', 'The North Face', 'collection', 'utility', 'jumper'. As a result, it can be seen that the Gorpcore is also regarded as a part of outdoor, fashion, coordination, and casual wear.