• 제목/요약/키워드: branch length threshold

검색결과 6건 처리시간 0.024초

여러 입력 여러 출력 시스템에서 길이 먼저 살펴보기와 가지 길이 문턱값을 바탕으로 둔 준최적 복호 (Near ML Decoding Based on Metric-First Searching and Branch Length Threshold for Multiple Input Multiple Output Systems)

  • 안태훈;강현구;오종호;송익호;윤석호
    • 한국통신학회논문지
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    • 제34권8C호
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    • pp.830-839
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    • 2009
  • 이 논문에서는 여러 입력 여러 출력 시스템에 알맞은 준최적 복호 방법을 하나 다룬다. 제안한 방법은 길이 먼저 살펴보기로 바탕으로 둔 바, 슈노르-오히너 늘어놓기와 가지 길이 문턱값을 써서 신호를 복호하는 데 드는 계산량을 줄인다. 제안한 방법의 비트오류율 성능은 최적 성능에 매우 가까우면서 계산량은 다른 준최적 복호기들보다 적다는 것을 모의실험으로 보인다.

등고선 추출을 위한 적응적 길이 임계화 (Adaptive Segment-length Thresholding for Map Contour Extraction)

  • 박천주;오명관;전병민
    • 한국콘텐츠학회논문지
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    • 제3권4호
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    • pp.23-28
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    • 2003
  • 본 연구는 지형도 영상으로부터 등고선 성분을 추출하는데 있어 대상 영상에 적응하여 결정되는 길이 임계치를 이용한 적응적 길이 임계화 방법에 관한 것이다. 우선, 적응적 길이 임계치는 주요 기호의 인식 후, 뒤따르는 고도치 영역에 대한 투영 히스토그램의 에지 검출을 통해 계산된 두 에지간의 거리로 결정된다. 그런 후, 분기점 탐색과 주변 흑화소 제거에 의한 단선화가 수행되고, 길이 임계화를 통해 등고선 성분을 추출한다. 제안 방법을 실험에 적용한 결과, 최종 추출된 등고선 성분 내에 비등고선 성분이 약 2.41% 포함되었으며, 97.59%는 등고선 성분인 것으로 나타났다.

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Diazinon이 계배(鷄胚)의 기형 유발에 미치는 효과 I. 계배(鷄胚) 형태와 콜린성 봉쇄약물에 미치는 효과 (Teratogenic effects of diazinon in chick embryos I. Effects of diazinon treatment on morphology and cholinergic blocking agents)

  • 김종수;김곤섭;김양미;최원영;손성기;허정호;이주홍
    • 대한수의학회지
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    • 제34권1호
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    • pp.49-54
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    • 1994
  • Teratogenic effects of diazinon were assessed on morphology of chick embryos cholinergic blocking agents. Diazinon at doses ranging from 25 to $2000{\mu}g/egg$, was injected on Day 3 of incubation. $TD_{50S}$, were different for the various teratogenic sings such as wry neck, micromelia, abnormal feathering, abnormal beak and curled claws. The threshold dose for wry neck was higher than the threshold dose for other signs; $40{\mu}g/egg$ produced substantial micromelia, abnormal feathering, abnormal beak and curled claws, but gave no sings of wry neck. In contrast to the teratogenic doses, the $LD_{50}$ of diazinon was very high(above $2000{\mu}g/egg$). One of the characteristics of diazinon-induced teratogenesis was reduction of body weight(78.8%) and body length(73.8%). Maximal teratogenic effects, scored as sings of retarded growth, wry neck, micromelia, abnormal feathering, abnormal beak, and curled claws, were produced when the insectcide was administered on the third or fourth day. The threshold dose for type II teratogenic sings including wry neck and short neck was higher than for type I including micromelia and abnormal feathering. Morphorlogical studies, using atropine and gallamine, suggested that nicotinc but not muscarinic receptors may be involved in the mechanism of diazinon-induced type II malformations.

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참다래 과수나무의 바람 피해 저감을 위한 실험적 연구 (Experimental Study for Reducing Wind Damage on Kiwi Fruit Plant)

  • 강종훈;임대현;이상준
    • 유체기계공업학회:학술대회논문집
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    • 유체기계공업학회 2006년 제4회 한국유체공학학술대회 논문집
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    • pp.263-264
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    • 2006
  • In this study, the threshold wind speed that causes physical damage on Kiwi fruit plant was investigated through wind tunnel experiments. Total 30 samples of Kiwi fruit branches were tested. On average, the wind speeds for tearing leaves and breaking side branch from the main branch were about 20m/s and 21.7m/s, respectively. For the cases of broken branches, the average length and diameter of the branches were 587.5mm and 7.2mm, respectively. The discoloration and dehydration of Kiwi plant were also observed by photographing leaves and branches after 24 hour later of the wind damage. In addition, the shelter effect of porous wind fences which have been used at agricultural districts was examined with varying several parameters.

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Population characteristics of the bivalve Ruditapes philippinarum from Cheju Island coasts, Korea

  • Silina, A.V.
    • 한국패류학회지
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    • 제26권3호
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    • pp.227-234
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    • 2010
  • A comparative analysis of size and age structures of coastal subfossil shell assemblages of the shortnecked clam Ruditapes philippinarum from open and protected bays of Cheju Island (Korea) was carried out. On the whole, taking into account the damage of small fragile shells, size and age structures of the shell assemblages corresponded to the classical curve of bivalve population distribution when its mortality diminishes with age increase up to a certain threshold. It was found that shell samples from open bays of the western, southern and eastern coasts included shells of smaller and younger individuals (L ${\leq}$ 40 mm, ${\leq}$ 4 years) than samples from the eastern protected bay (L ${\leq}$ 54.5 mm, ${\leq}$ 6 years). Evidently, strong wave activity was the reason for a short life-span of the clams from the open areas. Growth was investigated retrospectively by annual growth rings on the shells. Growth rates of the clams from the various coasts of Cheju Island differed. However, growth rates of the clams from different biotopes at the same (eastern) side of the Island were similar. Shell height/length and width/length ratios statistically significantly increased with the clam age increase. Most likely, the reason for such shell shape alteration is that more conglobated individuals more survive being more energy-optimal than oblong specimens.

외이도-유양동-귀뒤바퀴피부 누공환자에서 수술 전, 후의 외이도 공명의 변화 (The Changes of External Ear Resonance after Surgery for Repair of the Postauricular Meato-Mastoid Cutaneous Fistula)

  • 김상준;강명구;정성욱;이동근
    • 임상이비인후과
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    • 제29권2호
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    • pp.235-239
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    • 2018
  • Due to the structure with one end closed, the external ear resonance effect in which the high frequency is amplified can be generated, and the sound can be perceived well. The external ear resonance normally has a first peak and a second peak. On average, the first peak has a gain of 18.6 dB at 2620 Hz and the second peak has a gain of 18.2 dB at 4210 Hz. The resonance of the external auditory canal changes with the state of the tympanic membrane, the presence of the ventilation tube, and the structure (length, diameter, shape) of the external auditory canal. A patient with a postauricular meatomastoid cutaneous fistula was admitted to the hospital with a foreign body which is the molding of the hearing aid. After removal of the foreign body, the resonance of the external auditory canal was lost and the subjective sound cognitive ability decreased. In the case of postauricular meatomastoid cutaneous fistula, we confirmed the improvement of sound cognitive ability, the change of pure tone hearing threshold, and the change of the external ear resonance after reconstruction of the ear canal without middle ear reconstruction.