• Title/Summary/Keyword: 출현률

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감마선이 Artemia 알의 부화에 미치는 영향

  • 김원록;김진규;이영근;이창주;장화형
    • Proceedings of the Korean Nuclear Society Conference
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    • 1998.05b
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    • pp.720-724
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    • 1998
  • 감마선이 Artemia 알의 부화에 미치는 영향을 알아보고자, 10Gy, 100Gy, 3kGy, 6kGy과 9kGy의 선량으로 건조 상태의 알을 조사한 후 부화율과 nauplius기의 출현률을 조사하였다. 1kGy 이하의 방사선 조사군에서는 부화율과 nauplius기의 출현률이 대조군에 비하여 높게 나타났다. 3kGy 방사선조사군의 경우 대조군과 유사한 부화율을 보였으나 nauplius기의 출현률은 감소하였다. 6kGy의 방사선조사군에서는 알들의 부화 지연과 부화율의 감소가 뚜렷하였다. 50%의 부화율을 나타내는 선량은 약 5.5kGy였으며, 9kGy에서는 100% 치사선량을 나타내었다. 본 실험에서 조사한 선량증에서 비교적 낮은 선량의 범위에서는 이온화방사선에 의하여 Artemia 알의 부화시간 단축 및 부화율이 다소 증가하는 결과를 보였다. 따라서 이온화방서선을 이용한 Artemia 알의 부화률을 촉진지킬 수 있는 적정 선량에 대한 연구는 상업적으로도 가치가 있다고 생각되며, 향후 이에 대한 추가적인 연구를 통한 상업적인 활용이 기대된다.

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Minimum Chi-square estimation and the bootstrap (최소카이제곱추정과 붓스트랩)

  • 정한영;이기원;구자용
    • The Korean Journal of Applied Statistics
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    • v.7 no.2
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    • pp.269-277
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    • 1994
  • Bootstrap approximation is compared with ordinary asymptotic method in the context of minimum chi-square estimation through application in a real problem. Fixed interval search method is shown to be superior over a random interval search method or Newton-Raphson method. All the procedures are implemented by S-Plus functions.

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Correlation of Zoysia Grass (Zoysia. spp) Survival, Reproduction, and Floret Appearance Rates to Aid in Development of New Hybrid Zoysia Grass Cultivars (잔디 교잡 품종 개발을 위한 잔디 생존률, 재생산률 및 꽃대 출현률과의 상관관계)

  • Han, Gyung Deok;Jung, Ji Hyeon;Chung, Yong Suk
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.66 no.3
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    • pp.265-269
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    • 2021
  • This study was conducted to provide primary data through analysis of zoysia grass genetic resources to develop grass cultivars with beneficial novel properties. Zoysia grass (Zoysia. spp) is native to Korea, and is mainly propagated through stolons. However, since seed coat treatment technology was developed, the breeding of sexually reproductive grass variants has become possible, necessitating characterization of the floret appearance rate in the secured zoysia grass genetic resource before developing sexually reproductive cultivars. In this experiment, 549 grass lines were examined, revealing that florets appear in only 43 lines (7.81%). Survival rates after transplantation, and stolon generation rates displayed a significant positive correlation (Rho = 0.44). Survival rates after transfer, and rates of stolon production displayed very low correlations with floret appearance (Rho = -0.11 and Rho = -0.06). No significant results were obtained in 43 lines that displayed >20% floret appearance. To breed sexually reproductive grass variants, it is thus necessary to secure more genetic resources, considering the low rate of floret appearance. Finding traits that predict floret appearance at an early stage is also required.

Seasonal Variation of Infection by Three Species of Symbiotic Copepods in Clam, Tresus keenae (왕우럭에 공생하는 요각류 3종에 대한 감염률의 계절 변동)

  • Moon, Seong-Yong;Rha, Sung-Ju;Yoon, Ho-Seop;Choi, Sang-Duk
    • Journal of Aquaculture
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    • v.19 no.4
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    • pp.236-241
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    • 2006
  • Seasonal variation of the infection by three species of symbiotic copepods in clam, Tresus keenae was investigated in south coast of Korea. The prevalence and abundance of three symbiotic copepods showed seasonal variation with a peak in winter. Reproduction of the copepods occurs from early autumn to spring as indicated by higher ratio of gravid copepods. The frequency distribution of Lichomolgus inflatus, Pseudomyicola spinosus and Anthessius progectus in their host population could be fitted with negative binominal distribution. Results from the present study suggest that seasonal fluctuation in prevalence, relative density and mean intensity is related to temperature and life history of the symbiotic copepods.

Relationship between excystment and abundance of HABs off the southern coast of Korea (남해안연안에서 적조생물 휴면포자 발아와 유영세포 출현과의 관계)

  • 이창규;임월애;정창수;조용철;김학균
    • Proceedings of the Korean Society of Fisheries Technology Conference
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    • 2000.05a
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    • pp.204-205
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    • 2000
  • 최근들어 우리나라 남해안연안은 내만역을 중심으로 편모조류에 의한 적조가 빈번히 발생하고 있는데, 이들 적조는 지역별, 시기별로 일정한 주기성을 보이면서 출현하고 있다. 이러한 적조의 시초는 무엇보다도 적조생물이 형성하는 휴면포자의 발아와 상관성이 있을 것으로 추정된다. 따라서 본 연구에서는 우리나라연안에서 출현하는 주요 적조원인생물 휴면포자의 발아률과 유영세포의 출현량을 조사함으로써 휴면포자의 발아와 유영세포 출현량과의 관련성 여부를 알아보았다. (중략)

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Application of Seed Vigor Test for Predicting Field Emergence in Azuki Bean (Vigna angularis Wight) (팥 포장출현력 예측을 위한 종자세 검사)

  • Jeong, Gwan-Seok;Na, Young-Wang;Shim, Sang-In;Kim, Seok-Hyeon
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.59 no.3
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    • pp.341-349
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    • 2014
  • Field emergence of Azuki bean is poor due to hard seed coat as compared to other legumes. In this study, an attempt was made to develop prediction method with regression analysis based on various seed vigor tests in laboratory for field emergence of azuki bean. Azuki bean seeds artificially aged to provide various levels of seed quality were evaluated by the standard germination test (SGT), cold germination test (CT), cool germination test (CGT), complex stressing vigor test (CSVT), tetrazolium(TZ) vigor test and electroconductivity test. The SGT was suitable for predicting the field emergence in the unaged high vigor seeds. The abnormal seedling percentage and shoot length in the CGT were highly correlated with field emergence of moderate vigor seeds artificially aged for 2 days. Electroconductivity, seed viability in the CSVT, and vigor and predicted germinability in the tetrazolium vigor test were also useful for predicting field emergence. Percent of ungerminated seed in the CSVT was correlated with field emergence in the low vigor seeds artificially aged for 4 days. In a stepwise multiple regression analysis, seed viability in the SGT, normal seedling percentage and dry matter weight in the CGT accounted for 86.9% of the predicted value of field emergence in azuki bean.

Growth Characteristics of Early Peduncle Developing Plant in Korean Ginseng(Panax ginseng C.A. Meyer) (인삼에서 조기 화경출현개체의 생육특성)

  • 정찬문;남기열;김요태
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.34 no.1
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    • pp.92-97
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    • 1989
  • The study has carried out to investigate the possibility of application of the emerged-peduncle at the 2 year -old plant for ginseng breeding. In the 2 and 3 year-old plant, growth habits of aerial parts of plants that had the inflorescence showed higher vigor in leaf length, number of leaves, rate of fruitage and fertility, and roots yield than those of non-inflorescence. Generally, characteristics such as stem diameter, stem length, leaf length and number of leaves showed highly significant positive-correlation with root weight and fruitage. The trends of characteristics of plant that has inflorescence at the 2 year-old plant was shown one-year faster pattern than the plant that has non-inflorescence. As these results, selection of the plants which have inflorescence at the 2 year-old plant will provide valuable aid for ginseng breeding.

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A Study on Hangul Text Compressing Using the Structural Feature of Hangul (한글의 형태적 특성을 이용한 한글 문서 압축 기법에 관한 연구)

  • Lee, Gi-Seog;Kim, Yoo-Sung
    • The Transactions of the Korea Information Processing Society
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    • v.3 no.5
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    • pp.1294-1306
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    • 1996
  • To achieve high compression ratio for Hangul texts, in this paper two text compression algorithms which use the structural feature of Hangul, the frequency of postpositional words, are proposed. The performances of these proposed algorithms are also compared with previous text compression algorithms. The proposed compression algorithms named HLZ77 and HLZW come out from the modification of previous algorithms LZ77 and :ZW, respectively. The major distinction of the proposed ones is that the proposed algorithms use the fixed dictionary of selected postpositional words that appear most frequently in Hangul texts. The performances of HLZ77 and HLZW also are compared with those of LZ77 and LZW, respectively, with respect to the compression ratio. According to the result of performance study, the proposed algorithms are better than the previous algorithms for descriptive Hangul text snce the structural feature of Hangul is helpful to achievement of high compression ratio.

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Effect of Humenolepis nana infection on immunological responses of mice to sRBC (마우스에 있어서 왜소조충 감염이 sRBC에 대한 면역능에 미치는 영향)

  • Lee, Jae-Gu;Yuk, Sim-Yong;Park, Bae-Geun
    • Parasites, Hosts and Diseases
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    • v.27 no.1
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    • pp.23-34
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    • 1989
  • In an attempt to investigate the effect of Hymenolepis dana infection on immunological responses to sRBC in ICR strain of mice, cellular and humoral immune responses were chronologically monitored after sensitization with sRBC. Mice weighing about 20 g were allocated into artificial and natural infection groups. The shell-free eggs of H. dana were inoculated into mice on the day 0 (initial) and day 10 in the former group, and praziquantel (25 mg/kg/day) was administered for 3 days to the one half of the mice at the 15th day after the first inoculation and to all of the mice in natural infection group. In artificial infection group, the delayed-type hypersensitivity (DTH) to sRBC was considerably decreased on the day 10 after the first inoculation, and then elevated gradually to normal. Eosinophils in the peripheral blood increased slightly. The hemagglutinin (HA) and hemolysin (HE) titers during the early stage were shown to be more or less higher than those of control. Thereafter, the titers were returned to normal, followed by a transient decrease on the day 15 post-infection. The sRBC rosette and antibody-treated rosette-forming capacities on the day 15 post.infection were temporarily lowered but became higher thereafter. The mucosal mast cells (MMC) in the small intestine were gradually increased to make a peak on the day 10 post-infection and then maintained more or less at lower level. After praziquantel treatment, the DTH and the number of eosinophils were decreased slightly and the MMC number and sRBC rosette-forming capacity were considerably decreased. The titers of HA and HE and antibody-treated rosette-forming capacity, however, were elevated in general. In natural infection group, the DTH, the number of eosinophils, and MMC which were elevated due to H. dana infection were gradually returned to normal after prasiquantel treatment. The titers of HA and HE which were decreased by parasite infection were increased to normal after the treatment. However, the capacities of sRBC rosette or antibody-treated rosette formation were maintained at low levels in spite of the treatment. These results revealed that the immune responses to sRBC were significantly activated during H. dana infection, although they were transiently decreased during the days 10~15 post-infection.

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