• Title/Summary/Keyword: Drifting

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First Record of the Two Driftfish, Psenes maculatus, and Psenes cyanophrys (Nomeidae: Perciformes), from Korea (경남 통영해역에서 발견된 한국 미기록 노메치과 어류 2종 Psenes maculatus와 Psenes cyanophrys (노메치과, 농어목)에 대하여)

  • Myoung, Jung-Goo;Cho, Sun-Hyung;Kim, Jong-Man;Kim, Yong-Uk
    • Korean Journal of Ichthyology
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    • v.13 no.3
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    • pp.195-200
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    • 2001
  • Psenes maculatus and P. cyanophrys of family Nomeidae were collected for the first time off the coast of Tongyeong, Kyongsangnam-do, Korea. Specimens were catched with drifting seaweed patches on June and July, 1998. Young Psenes maculatus has six black bands ('<' shape) on the body, and 'Ttimul-reung-dom' is proposed as the Korean name. Psenes cyanophrys differs from P. pellucidus in having a compressed oval body shape scales on the check, and 16 longitudinal lines on the body. 'Jul-mu-nui-mul-reung-dom' is proposed as the Korean name.

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Current Properties and Evaluation of Electronic Ink in Electrophoretic Display (전기영동 디스플레이에서 전자 잉크의 전류 특성 및 평가)

  • An, Hyeong-Jin;Kim, Young-cho
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.33 no.1
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    • pp.31-36
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    • 2020
  • An investigation was conducted to determine whether the ratio of the fluid to the charged particles affects the panel reflexibility rate and the drifting current flowing in the panel, in electrophoretic-based electronic paper. In this regard, three panels were produced in this study with the ratio of the charged particles to the fluid set as 1:5, 1:1, and 5:1. Each sample was driven using an identical input pulse, for which the current flowing in the panel and the output voltage of the photodiode were measured for the panel reflexibility rate. Consequently, the drifting current initially exhibited a peak value and a saturated value at a later point. This value was proportional to the ratio of the charged particles, and it was similar to this ratio when it is higher than 1:1. The output voltage of the photodiode due to the panel reflexibility rate was proportional to the ratio of the charged particles. However, the response speed decreased if the ratio was higher than 1:1. It is expected that the results of this study will contribute to the analysis of the charging of charged particles in electrophoretic-based electronic paper, and the selection of an appropriate concentration.

Underwater Target Discrimination Using a Sequential Hypothesis Test (순차적 가설 검증을 이용한 수중 표적 판별)

  • Jeong, Young-Heon;Hong, Sun-Mog
    • Journal of the Korean Institute of Telematics and Electronics B
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    • v.33B no.1
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    • pp.6-14
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    • 1996
  • In this paper we present an algorithm to discriminate an underwater target under track against an acoustic counter-measure(ACM) source, based on a sequential hypothesis test. The ACM source is separated from the target under track and generates, while drifting, measurements with false range and Doppler information. The purpose of the ACM is to mislead the target-tracking and to help the true target evade a pursuer. The algorithm uses as a test statistic a function of the innovation sequences from extended Kalman filters to estimate the target dynamics and the drifting position of the ACM source. Numerical experiments on various scenarios show that the proposed algorithm discriminates the target against an ACM source very fast with a high probability of success.

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Sargassum Golden Tides in the Shinan-gun and Jeju Island, Korea (한국 신안과 제주 연안에서 모자반(Sargassum) 유조의 대량발생)

  • Hwang, Eun Kyoung;Lee, Seung Jong;Ha, Dong Soo;Park, Chan Sun
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.49 no.5
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    • pp.689-693
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    • 2016
  • Sargassum golden tides occurred in Shinan-gun and Jeju Island, Korea, between January and May 2015. In Shinangun, 5,180 tons of Sargassum were removed from 3,339 ha of coastline, while 20,000 tons were removed from Jeju Island. The huge floating masses of seaweed caused damage to fisheries in Shinan-gun including abalone sea cage, Pyropia and Saccharina farms off the southwest coast of Korea. Drifting Sargassum also washed ashore on Jeju Island. The species of Sargassum in these golden tides was identified as S. horneri (Turner) C. Agardh, based on morphology and molecular data, and it appears to have originated from the East China Sea. This is the first report on Sargassum golden tides causing damage to fisheries in Korea.

Astudy on the classification of Eastern Coastal line of korea from the view point of Prevailing Wave Direction (탁월파랑에 의한 동해안선 분류의 조사연구)

  • 이원환;이정태
    • Water for future
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    • v.11 no.1
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    • pp.39-46
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    • 1978
  • The approaching deep water wave heights and directions affect the wave energy which is carried to the coast. By studing the relations between the longshore wave energy theory and the evolution of coastline, writer can arrive following conclusion. The longshore lottoral drifting affects to a great deal the formation of the coast, and by investigating on the eastern coastal geomophorogy of korea, the theory was proued as a true and made it possible to an approaching to the subdivided classification of eastern coast of lorea. That is to asy that angle taken by the level between the wave crest line of prevailing wave(NE) and the coastline was measured as less than 15#, and in the area neighboring the river which served as source of Sand parrticles, there are grand scale formation of sand beach expectable, in the other hand the formation of sand beach in case of $35^{\circ}{\leq}{\alpha }o{\leq}55^{\circ}$ which represents the vivid phenomena of longshore littoral drifting was proved not influencial but rather transformed into a rocky coast. Depending on the above facts the writer classified general shape of the coast affected by the vivid wave action into the following three, (1) The equilibrium beach. (2) Erosinal beach. (3) Geomophorogical beach, and made the sandy and rocky coast are subdivided as S-A.B.C. and R-DEF.

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Drift Handling in Object Tracking by Sparse Representations (희소성 표현 기반 객체 추적에서의 표류 처리)

  • Yeo, JungYeon;Lee, Guee Sang
    • Smart Media Journal
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    • v.5 no.1
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    • pp.88-94
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    • 2016
  • In this paper, we proposed a new object tracking algorithm based on sparse representation to handle the drifting problem. In APG-L1(accelerated proximal gradient) tracking, the sparse representation is applied to model the appearance of object using linear combination of target templates and trivial templates with proper coefficients. Also, the particle filter based on affine transformation matrix is applied to find the location of object and APG method is used to minimize the l1-norm of sparse representation. In this paper, we make use of the trivial template coefficients actively to block the drifting problem. We experiment the various videos with diverse challenges and the result shows better performance than others.

Direct release of embryonic sporophytes from adult Nereocystis luetkeana (Laminariales, Ochrophyta) in a high latitude estuary

  • Ulaski, Brian P.;Konar, Brenda
    • ALGAE
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    • v.36 no.2
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    • pp.147-154
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    • 2021
  • Kelp life history pathways alternate between macroscopic sporophytes that produce spores and microscopic gametophytes that produce gametes. Occasionally, an alternative pathway is seen. This study examined the circumstances by which the high latitude estuarine bull kelp, Nereocystis luetkeana, foregoes the "free-living microscopic stages by releasing embryonic sporophytes directly from sori. Sori were collected from adult N. luetkeana sporophytes from eight locations within Kachemak Bay, Alaska in 2018 and 2020 to examine spatial and temporal development of embryonic sporophytes on sori. Distinctions were made between sori collected from first-generation and overwintered adults to assess the influence of parental age on embryonic sporophyte release. Further distinctions were made between sori collected from attached and drifting individuals to assess the influence of the status of parental attachment to substrate on embryonic sporophyte release. Inspection of propagules released from sori after 48-h incubations indicated that embryonic sporophytes were occasionally released alongside viable spores. Though embryonic sporophytes were released from sori as early as spring, it was not evident that they were bound by seasonal or spatial limits. The percent of propagules that were embryonic sporophytes ranged from 0% to 100% but were not significantly different between first-generation and overwintered adults, nor were they different between attached and drifting individuals. Nevertheless, the characteristic of directly releasing embryonic sporophytes from adult sporophytes might have ecological advantages for N. luetkeana.

Comparison of the Reproductive Characteristics of Sweetfish Plecoglossus altivelis in the Main Streams of Jeju Island (제주도 주요 하천에 서식하는 은어(Plecoglossus altivelis)의 번식 특성 비교)

  • Kim, Han-Jun;Park, Chang-Beom;Lee, Young-Don;Choi, Young-Ung
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.52 no.5
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    • pp.496-510
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    • 2019
  • We investigated the reproductive characteristics of the sweetfish Plecoglossus altivelis, including changes in the gonadosomatic index (GSI), frequency of gonad developmental stages, and abundance of drifting larvae, in three streams (Gangjeong, Yeonoi, and Ongpo) on Jeju Island from May 2004 to December 2005. The GSI values of female P. altivelis in all Jeju streams began to increase in September and reached a maximum in October and November. Peak GSI values in males occurred in Gangjeong from October to November, in Yeonoi from November to January, and in Ongpo from September to October. The gonadal development of P. altivelis was classified into four stages: growth (March to October), maturity (September to December in females; July to December in males), spawning (September to January), and degeneration (October to March in females; after November in males). Drifting larvae were collected from October to January. These results suggest that the main spawning activity of P. altivelis in Jeju streams occurs from October to November. The information about the reproductive characteristics of P. altivelis obtained in this study is critical to fishery management for this species.