• Title/Summary/Keyword: Jeju (Cheju)

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Voltage quality and Network Interconnection Standard Suitability in Jeju-Hangwon Wind Power Generation Farm (제주행원 풍력발전단지의 전압품질 및 연계기준 적합성 분석)

  • Kim, Se-Ho;Kim, Eel-Hwan;Huh, Jonhg-Chul
    • Journal of the Korean Solar Energy Society
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    • v.26 no.2
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    • pp.53-59
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    • 2006
  • The number of wind generation installations are growing substantially in Jeju, Korea. Many of these installations are significant in size and directly connected to the distribution system. Utility grid interconnection standards for interconnecting non-utility distributed generation systems are essential to both power system company and generation company. These interconnection standards are important to utilities, customers, wind generation manufactures and nation. In this paper, it is investigated the voltage quality and the suitability of Jeju-Hangwon wind power generation farm by network interconnection technology standard.

Bus Voltage Analysis of Substation Connected to the Wind Generation Farm (풍력발전단지와 연계된 변전소의 모선전압 분석)

  • Kim Young Hwan;Hyun Gil Ju;Ko Seok Bum;Yang Ik Jun;Na Kyoung Yun;Kim Se Ho
    • Proceedings of the KIEE Conference
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    • summer
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    • pp.236-238
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    • 2004
  • In recent years wind turbine technology has undergone the rapid development in response to the demands for increased use of renewable sources of energy. Using wind turbines for production of electrical energy requires reliable operation. The increased share of wind power in electrical system makes it necessary to have grid-friendly interfaces between the wind turbines and the grid in order to maintain power quality. Increasingly wind turbines are being connected into electricity distribution system. The grid-connected wind power stations have many impacts on power systems such as voltage variations, harmonics. The paper investigates the influences of grid-connected wind power generation system on substation bus voltage.

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Prospect and Influence Analysis of Jeju Wind Power System (제주풍력 전망 및 계통영향 분석)

  • Kim, Yeong-Hwan;Kang, Jee-Yoon;Byeon, Kun-Ik;Woo, Hyun-Chul;Kim, Gun-Hoon;Kim, Se-Ho
    • Proceedings of the KIEE Conference
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    • 2008.07a
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    • pp.275-276
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    • 2008
  • Construction of wind power plant is rapidly increasing since Jeju is known as the most suitable regarding wind power plants in Korea. But implementing wind power generation inevitably introduces new challenges due to its intermittent nature. In the paper, it is introduced the prospect of wind plant construction and influence analysis in Jeju power system.

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Prevalence of Cognitive Impairment and Related Factors Among the Elderly in Rural Communities of Jeju Province

  • Ko, Keumja;Jung, Min;Hong, Sungchul
    • Journal of Korean Academy of Nursing
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    • v.33 no.4
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    • pp.503-509
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    • 2003
  • Purpose. The purpose of this study was to survey the prevalence rate of cognitive impairments and to identify the factors influencing cognitive impairment in the elderly in rural communities of Jeju Province. Methods. 590 elderly in 6 rural communities of Jeju Province were interviewed, using a questionnaire consisting of sociodemographic characteristics, health behavior, quality of life, and MMSE-K Results. Prevalence of cognitive impairment was 33.1 % (39.1 % of females, 16.76% of males). Prevalence of dementia was 12.4% (16.3% of females, 2.87% of males). Factors related to cognitive impairment were age, sex, education, standard of living, employment status, and subjective health state. Conclusions. In community health care for the elderly, factors relating to cognitive impairment have to be considered. When planning community health care, priority should be given to the elderly; who need care but live alone; who lack social support; who have a low standard of living; who experience discomfort in the activities of daily living; who believe they are not in a good state of health; or whose life satisfaction is low.

Genetic Analysis of Ancient Bones of Cervidae Animals from Archaeological Site in Jeju, Korea

  • Kang, Min-Chul;Han, Sang-Hyun;Jung, Yong-Hwan;Oh, Ju-Hyung;Kim, Gi-Ok;Ko, Jae-Woen;Oh, Moon-You
    • Animal cells and systems
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    • v.11 no.2
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    • pp.147-153
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    • 2007
  • DNA extracted from ancient bones of Cervidae animals was examined to identify the species and to determine the phylogenetic relationships to those from extant cervids. Abundant ancient bones were excavated from Kumsung archaeological site in Jeju Island, Korea, and were identified as Cervidae animals based on morphological features of their antlers and lower mandibles. Their mitochondrial DNA (mtDNA) control region (CR) was partially sequenced and subsequently compared with those previously reported in database. The results confirmed that the ancient sequences are lineage of Cervidae. On the phylogenetic trees constructed using the sequence diversity of the CR sequences of family Cervidae, the ancient DNA sequences were found on distinct clusters. The ancient sequences were located in the subfamily Capreolinae cluster, and six ancient sequences were closely related to those of extant Korean roe deer in Jeju Island and Korean Peninsula. Consequently, the results of this study suggest that the roe deer inhabited Jeju Island in ancient times. However, there is no evidence for the existence of subfamily Cervinae, including Sika deer, while it has been described in several historical records. The results suggest that this finding could contribute to understanding of the origin and phylogenetic relationships of extant and ancient roe deer on Jeju Island.

Mobile digital storytelling using Hamel (하멜을 이용한 모바일 디지털 스토리텔링)

  • Ko, Seok-Ha;Lim, Ji-Hoon;Kim, Seong-Baeg;Moon, Hae-Gyoung;Hyun, Jung-Suk
    • Proceedings of the Korea Contents Association Conference
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    • 2006.11a
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    • pp.172-175
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    • 2006
  • Hamel has a scholastic value as the first person, who announces Jeju and Korea to Europe. However, there has been little research on developing digital contents except a few books about Hamel. We develop an educational game on PDA using Hamel, based on Hamel character, Jeju's unique culture, multimedia technology, and so on. Compared with the previous games, it is different from the form of gathering points and has various game scenarios through interactions between Hamel character and game space. The structure of this game, which connects Jeju culture and cyber space together, represents the form of a digital storytelling. You can study through this game. It uses quizzes about Jeju culture, crossword puzzles, finding a sequence, finding differences between two pictures to teach users, and fixing pieces of a figure, etc. When we made the game, we divided it into some independent modules to make new game series easily using contents of the other provinces.

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Cytotoxic Activities of Green and Brown Seaweeds Collected from Jeju Island against Four Tumor Cell Lines

  • Kim, Kil-Nam;Lee, Ki-Wan;Song, Choon-Bok;Jeon, You-Jin
    • Preventive Nutrition and Food Science
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    • v.11 no.1
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    • pp.17-24
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    • 2006
  • Methanolic and aqueous extracts from 37 seaweed species (10 green and 27 brown seaweeds) collected from Jeju Island coast were prepared at high ($70^{\circ}C$) and room ($20^{\circ}C$) temperatures and examined for cytotoxic activity against 4 tumor cell lines: U937 (human monoblastoid leukemia cell line), HL60 (human promyelocytic leukemia cell line), HeLa (woman cervical carcinoma cell line) and CT26 (mouse colon carcinoma line). Both MeOH extracts of Desmarestia tabacoides and Dictyota dichotoma possessed strong cytotoxic activities against all the tumor cell lines tested, but the aqueous extract exhibited no activity. On the other hand Ecklonia cava showed strong cytotoxic activities for the $20^{\circ}C$ aqueous extract against the three tumor cells except HeLa cell. Sagassum coreanum and Sagassum siliquastrum $20^{\circ}C$ aqueous extracts also exhibited strong cytotoxic activities against U937, HL60, HeLa cells. Even though green seaweeds showed less activity than brown seaweeds, $20^{\circ}C$ aqueous extracts of Codium contractum and Codium fragile exhibited strong cytotoxic activities against HL60 or CT26 cells, respectively.