• Title/Summary/Keyword: Cheju-do

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Power Controlled Dual-channel UC Protocol for Mobile Ad Hoc Networks (Ad hoc 네트워크에서 전력 제어 기법을 사용한 Dual-Channel MAC 프로토콜)

  • Kang, Chang-Nam;Han, Do-Hyung;Lee, Eun-Ju;Jaw, Jeong-Woo;Lim, Jea-Yun
    • Proceedings of the Korean Society of Broadcast Engineers Conference
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    • 2007.02a
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    • pp.101-104
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    • 2007
  • Ad hoc 네트워크는 기반구조가 없는 무선네트워크이다. Ad hoc 네트워크는 재난지역, 군사지역, 홈 네트워킹 서비스, 텔레매틱스 서비스 같은 곳에서 응용될 수 있다. 최근Ad hoc 네트워크의 처리량을 향상시키기 위해 방향성 안테나를 사용하거나 이중채널을 사용하는MAC프로토콜이 제안되고 있다. DUBMAC프로토콜은 이중채널에 방향성 안테나를 사용하여 처리량 성능을 향상시킨 프로토콜이다. 본 논문에서는 DUDMAC프로토콜에 전력 제어 기법을 적용하여 네트워크의 처리량을 향상시키는 MAC 프로토콜을 제안한다. 제안하는 MAC 프로토콜은 새로운 블로킹 알고리즘을 사용하여 공간 재사용을 향상시킨다. 제안하는 블로킹 알고리즘은 RTS 또는 CTS 수신 시 블로킹 테이블에 저장된 수신세기를 사용하여 기존의 DUDMAC의 블로킹 영역을 FULL_BLOCKING 영역과 SEMI_BLOCKING 영역으로 구분하여 성능을 개선한다. 제안하는 MAC 프로토콜의 처리량 성능은 퀄넷 시뮬레이터 버전 3.8을 사용하여 확인하였다.

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A LATERAL CONTROL ALGORITHM FOE ROLL-TO-ROLL WEB SYSTEM BASED ON BACK-STEPPING APPROACH

  • Choi, Kyung-Huyn;Thanh, Tran Trung;Ko, Jeong-Beom;Kim, Su-Jin;Doh, Yang-Hoi;Kim, Dong-Soo
    • Proceedings of the KSME Conference
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    • 2008.11a
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    • pp.1091-1097
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    • 2008
  • Roll-to-roll based manufacturing plays an important role in producing devices at high speed with lower production cost in printed electronics and publishing industry. Web lateral control is one of the most important factors in improving the quality of product and contributes a considerable point in making devices at micrometer-level accuracy. In recent years, most algorithms proposed for web lateral control base on the Shelton‘s model for designing the feedback control system using the PI controller. Experimental results showed that the existing models do not fully describe the characteristics of the lateral dynamics for some typical operating conditions and so result in poor control algorithms. In this paper, a new lateral control algorithm is proposed for web lateral control system based on back-stepping approach. The outcome of this study proves the reliability throughout simulation results in Matlab/Simulink and comparison with the algorithms based on the existing results.

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Development of the Air-lifting & Suction-pumping System to Remove the Noxious Deposit in the Underwater (수중 유해성 유기퇴적물의 수거를 위한 Air-lifting & Suction-pumping System 개발)

  • Kim, Seoung-Gun;Song, Do-Sung;Kang, Mun-Kyu;Lee, Sang-Moo;Choi, Young-Chan;Ko, Yu-Bong
    • Proceedings of the Korea Committee for Ocean Resources and Engineering Conference
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    • 2002.10a
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    • pp.251-255
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    • 2002
  • Eutrophic matters accumulated on the bottom of sea, river and lake cause red tide phenomenon in ocean and outbreak green algae in river and lake. Systems are developed to remove the noxious deposit. But the existing systems remove not only the eutrophic matters but also natural materials, sand, pebbles etc. that should remain at the bottom. This paper describes a new system that can safely, and economically take away the noxious deposit in underwater. High pressure water jet is used to induce vortices in the triangular suction section, and air-lifting pump to lift up the deposit. The mixture of the water and deposit is filtered through the drum filters. An under camera shows the under water situation along the moving direction of the system that is controlled by a remote operator. This remote controlled moving system obliterate the necessity of the diver that usually costs high. The experimental results show the effectiveness of the suggested system.

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CheJu-do's Manjanggul, the world's Longest Lava Cave

  • Press, Yonhap
    • Journal of the speleological society of Korea
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    • v.41 no.1
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    • pp.27-33
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    • 1994
  • Tourists visiting Korea's resort island of Cheju-do often hear the legend of how the founders of the island's three original clans emerged from holes in the ground. They can even visit the site where three depressions remain in the ground -- one each for the Ko, Yang and Pu families.(omitted)

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Legal Approach to the Passage Issues of the Cheju Strait (제주해협 통항문제에 관한 법적 고찰)

  • Kim Hyun Soo
    • Proceedings of KOSOMES biannual meeting
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    • 2003.11a
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    • pp.35-44
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    • 2003
  • Considering possible legal and policy problems with regard to the Cheju Strait, a central issue is whether the Cheju Strait should be treated as Korean territorial sea or an international strait The claim that the strait is territorial sea has been based on the use of a straight baseline method of dermarcation With the use of straight baseline, Korea claims that the breadth of the Cheju Strait is only 20.7 miles at its narrowest point and therefore the strait becomes the territorial sea of Korea. The consideration cf marine pollution has weighed heavily in claiming the Cheju Strait as territorial sea. Pollution resulting from the accidents cf tankers caused by fire, collision, or stranding in the Cheju Strait and the Korea Strait would be enormous, affecting the entire coastal waters of the south coasts cf Korea's mainland and Japan's Tsushima Islands areas. Catastrophic pollution in the Cheju Strait could also come from the accidents cf large-size oil tankers passing through the Korea Strait from the Malacca Strait Although the Korean government considers the geographic and socioeconomic conditions sufficient to justify Korea's claim of the Cheju Strait as territorial sea, it believes that declaring it so would raise considerable legal conflicts with maritime states. In view of the legal difficulties and the need to meet the problems arising from the growing vessel traffic in the Cheju Strait, the sea lanes and traffic separation schemes may be considered an alternative to the internationalization of the Cheju Strait Even if the Korean government dose not do so, the regime of innocent passage should be applied to vessels passing through the Strait and should not suspend innocent passage through the Strait. Therefore, the Korean government needs to have a more legal, pragmatic, functional and managerial approach than a purely sovereign and selfish approach to the solution of legal matters of the Cheju strait For this purpose, the UN Convention on the Law of the Sea would serve as a guide and also self-restraint and cooperative approaches would become norms governing the resolution of the law of the sea issues in the Cheju Strait.

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A Study of the Ondol (Gudul, Floor Heating System) and Kitchen Space in the Traditional Houses on Jeju Island, Korea

  • Kim, Bong-Ae;Lee, Jeong-Lim
    • International Journal of Human Ecology
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    • v.4 no.1
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    • pp.15-23
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    • 2003
  • Jeju-do is a volcanic island located off the shore of the Korean peninsula facing the Pacific Ocean. The traditional housing styles of the Jeju Province, therefore, reflect the impact of these natural backgrounds and reveal different housing styles that are distinctive from those of mainland Korea. The purpose of this research is to analyze the peculiarities of the Ondol (floor heating system) and the kitchen space of traditional housing of Jeju Island in terms of lifestyles. This study shall employ two research methods: a literature review and field survey methods. The literature review shall focus on the observations of characteristics noted in previous studies of Jeju's private houses. The field survey shall employ field survey and interview methods originating from the ethnography of the culturological-anthropologist approach. (1) The Jeju-do Ondol system is a “Weibang-eudul” system which means one Gudul per fire hole. (2) The definition of terms for Gulmook show variations depending on the various regions on Jeiu-do. (3) Major facilities in Jeongji include Gulmook, Sotduck, and Busup. Gulmook is a heating facility and Sotduck refers to a cooking facility; Busup refers to a combination of heating, cooking, and illuminating facilities.

Studies on Eurytrema Pancreaticum [I] Infection rate and pathological changes (췌질(膵蛭)에 관(關)한 연구(硏究) [I] 감염율(感染率)과 병변(病變))

  • Jang, Du Hwan
    • Korean Journal of Veterinary Research
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    • v.9 no.2
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    • pp.7-18
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    • 1969
  • Researches to determine the infectious status on the pancreatic fluke, Eurytrema pancreaticum(Janson 1889) Looss, 1907, were made into several slaughter hauses at four different districts through seven years from 1963 to 1969. The infection rate showed 2962 positive of 5974 heads (49.6%) of cattle at the Seoul first slaughter hause in Seoul, 881 positive of 1021 heads (86.3%) in Cheju, and six(6) positive of 56 heads (11.1%) at Suwon, 58 positive of 306 heads(19.0%)at Joenju. The infection rate 53.1%, (2907 positive heads of total 7357 heads exammed) is the representative infection rate at the cattle eurytremiasis in Korea. It showed little variation through a year and was increased as compared with those of the past period, from 1915 to 1945. Fecal examinations in order to find out the local distribution of the pancreatic fluke were conducted on cattle, sheep, and goats raised in four districts, showing two(2) of 269 heads (0.7%) in Kyonggi-do, 41 of 212 heads (19.3%) in Cheju-do, and negative in both Chungnam-do and Joenbuk-do. When an artificial infection wss performed on rabbits and goats with metacercaria of the pancreatic fluke, Parenchyma of their pancreas were degenerated and the ducts were dilated. When cattle and sheep were infected naturally, the pancreatic ducts were also dilated, the wall was thickened, and adenomatous and epithelial hyperplasia was appeared. The conclusion, putting the foregoing pathological changes, has been arrived at chronic hyperplastic pancreatitis in the eurytremiasis of cattle, sheep, goats and rabbits.

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