• Title/Summary/Keyword: Duck-tail

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A Study on the Speed Effects of Afterbody Appendage for the Container Carrier (컨테이너 운반선의 선미부가물에 의한 속도성능 향상에 대한 연구)

  • Lim, Chae-Seong;Park, Dong-Woo
    • Special Issue of the Society of Naval Architects of Korea
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    • 2007.09a
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    • pp.32-42
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    • 2007
  • Container vessels are required to have a large KMT to load many containers which requires a wide transom stern form. The wide transom stern generates large stern waves particularly at the scantling draft. This means that reducing the stern wave leads to resistance reduction. Numerical analyses and Model tests for duck-tail of the stern part have been performed to reduce the resistance of the container vessel having the wide transom on the scantling draft and optimize the form of duck-tail with the change of the design parameter i.e. length and edge height. The optimized duck-tail increases the speed by 0.8 % at scantling draft.

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Three-dimensional Face Recognition based on Feature Points Compression and Expansion

  • Yoon, Andy Kyung-yong;Park, Ki-cheul;Park, Sang-min;Oh, Duck-kyo;Cho, Hye-young;Jang, Jung-hyuk;Son, Byounghee
    • Journal of Multimedia Information System
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    • v.6 no.2
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    • pp.91-98
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    • 2019
  • Many researchers have attempted to recognize three-dimensional faces using feature points extracted from two-dimensional facial photographs. However, due to the limit of flat photographs, it is very difficult to recognize faces rotated more than 15 degrees from original feature points extracted from the photographs. As such, it is difficult to create an algorithm to recognize faces in multiple angles. In this paper, it is proposed a new algorithm to recognize three-dimensional face recognition based on feature points extracted from a flat photograph. This method divides into six feature point vector zones on the face. Then, the vector value is compressed and expanded according to the rotation angle of the face to recognize the feature points of the face in a three-dimensional form. For this purpose, the average of the compressibility and the expansion rate of the face data of 100 persons by angle and face zone were obtained, and the face angle was estimated by calculating the distance between the middle of the forehead and the tail of the eye. As a result, very improved recognition performance was obtained at 30 degrees of rotated face angle.

A Study on the plant monitoring for artificial wetlands in the rivers (하천의 인공습지에 대한 식생변화 모니터링 연구)

  • Hong, Seung-Jin;Kim, Jung-Wook;Jung, Ju-Young;Kim, Duck-Hwan;Ahn, Kyung-Soo;Kim, Hung-Soo;Lee, Jong-So
    • Journal of Wetlands Research
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    • v.17 no.1
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    • pp.91-100
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    • 2015
  • The aim of this study is to compare and analyze plant monitoring results of 2012 and 2013 for three artificial wetlands of Binae, Sedo, and Okpo areas in Namhan river, Keum river, and Nakdong river respectively. As the results, the Binae wetland in 2013 shows the same environment with 2012, that is, Willow and Common reed were dominant and the distributed plants in the wetland were Phragmites japonica Steud, Carex dispalta Boott, and Humulus japonicus in lowland of river side. Especially, Humulus japonicus was increased in summer season and Willow was increased in lowland of 초원. In Okpo wetland, Water chestnut was appeared in 2013 which it was not in 2012. Reed distribution was reduced in 2013 comparing to 2012 but Pussy willow distribution was not changed in 2013. In Sedo wetland, Secondary grassland was artificially planted in 2013 and so the colony was changed to Chinese Lespedeza and also most of plant colony was changed to Colt's-tail. Therefore, we can know that wetted transition rather than dried transition will be occurred in the Binae wetland. However, the Okpo wetland has monotonic change and so the transition will be proceeded with long time. The Sedo wetland showed wetted and dried transitions exist together. Therefore, the wetland will be changed to Reeds, Common reed, and Willow colonies.

Life history of Echinopowphium recurvatum (Trematoda: Echinostomatidae) in Korea (한국에서의 오리극구흡충 (Echinoparyphium recurvatum)의 생활사)

  • 손운목
    • Parasites, Hosts and Diseases
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    • v.36 no.2
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    • pp.91-98
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    • 1998
  • The present study was performed to observe characteristics of the lifE history of Echinoparvphium recunpatum under both natural and laboratory conditions in Korea. A batch of Rcnix aunculnria corecna was collected from Sunamchon, one of the stream of West Naktonggang (River), in Kangso-gu, Pusan during August and September 1992. Out of 106 snails examined by crushing,52 (49.0%) were infected with larval E. recurvaum i.e. rediae, cercariae and metacercariae. Cercariae naturally shed from snails encysted in the snails of same species and loaches, but not in mud-snails. Adult worms were detected from chicks and ducks experimentally infected with metacercariae, but not from rats and mice. The average recovery rate of adults from chicks was 13.1%. Rediae were sac-like, $2.437{\;}{\times}{\;}0.317{\;}mm$ in average size, with a muscular pharynx and a brownish cecum which reached the anterior half of the body. Cercariae consisted of a spindle-shaped body ($0.262{\;}{\times}{\;}0.129{\;}mm$ in average) and a rod-like tail ($0.528{\;}{\times}{\;}0.056{\;}mm$ in average). In the cercarial body, 45 collar spines were observed on the head crown, and double rows of excretory ducts with fine granules were laterally arranged between the pharynnx and the ventral sucker. Metacercariae were spherical, $0.144{\;}{\times}{\;}0.142{\;}mm in average size, with thick hyaline outer and thin elastic inner walls, and many excretory granules. Adults were slender and more attenuated in the anterior end, $0.2760{\;}{\times}{\;}0.550{\;}mm$ in average size, and had 45 collar spines including four end group spines on both ventral corners. From the above results, it was confirmed that R. auriculnna corennc plays a pivotal role in the life cycle of 5. recuwatum as the first and/or second intermediate hosts in Korea.

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