• ALGAE
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• 제18권3호
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• pp.233-238
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• 2003

Cyanobacteria were dominant from June to September in the Nakdong River and the Hoedong Reservoir. Microcystis aeruginosa was dominant from June to September; Anabaena flos-aquae from June to August and Aphanizomenon flos-aquae from July to August. Cyanobacterial neurotoxins, Anatoxin-a and saxitoxin were analyzed by electrospray ionization-mass spectrometry with strains of Aphanizomenon flos-aquae NIES-81 and Anabaena flosaquae NIER-10002. Anatoxin-a was not detected from the cultured Anabaena flos-aquae nor from the wild samples. Low levels of saxitoxin were detected in the cultured Aphanizomenon flos-aquae however, those of field samples were below the detection limit.

• 한국통신학회논문지
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• 제22권7호
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• pp.1523-1533
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• 1997

Image registration is concerned with the establishment of correspondence between images of the same scene with translational, rotational, and scaling differences. The estimated transformation parameters between images are very important information in the field of many applications. In this paper, we propose a shape matching scheme for finding correspondence points for images with various differences, Tranditional solutions to this area are unreliable for the rotational and schaling changes between images, and the feature extraction of partially occluded scene. To solve those problems, dominant points on digital curves are detected by scale-space filtering, and initial matching is performed by similarity measure of cumulative curvatures for dominant points. For initial matching segments pairs, optimal matching points are calculated using dynamic programming.Finally, transformation parameters are estimated.

• 한국해양공학회:학술대회논문집
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• 한국해양공학회 2004년도 학술대회지
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• pp.143-148
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• 2004

In order to see physical characteristics of water masses and tidal currents in Gamak Bay, some field surveys have been conducted using ADCP, Aanderaa current meter and CTD from May 17 to June 3, 2004. The northwest of the bay appeared to have a high temperature and a high salinity so that it coincided with the previous results. The distribution of temperature and salinity seemed to reflect the characteristics of water masses. At the south mouth of the bay, a northwestward-southeastward flow was dominant at the surface layer while a northeastward-southwestward flow was dominant at the bottom layer.

• 한국자원식물학회지
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• 제23권3호
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• pp.242-247
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• 2010

This study was carried out to elucidate the effect of mulching materials on the growth of Chinese chive (Allium tuberusum Rottler) and weed control. Chinese chive was grown under five mulching materials, pine leaf, oak leaf, rice straw, rice hull and sawdust, at the Experimental Farm of Chungbuk National University from June 20, 2009 to September 30, 2009. Amaranthus mangostunus, Digitaria sanguinalis, Portuclaca. oleracea, Echinochioa crus-galli var. frumetacea and Setaria viridis were dominant weeds. Both pine and oak leaves were significantly effective mulching materials in terms of weed control indices in both nursery and field. Soil moisture contents were 1.2~3.7% higher in mulching, especially in oak leaf mulching. Mulching with pine leaf significantly increased plant height, sheath length, leaf length, bulb-, root- and leaf-weights and yield of Chinese chive, but there were no significant differences among the other mulching materials although better than those in non-mulching.

• 한국지진공학회:학술대회논문집
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• 한국지진공학회 2003년도 춘계 학술발표회논문집
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• pp.16-22
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• 2003

The focal mechanisms of the earthquakes occurred in 2001 and 2002 are analyzed to understand the regional stress and tectonics in and around Korean Peninsula. The forty -three fault plane solutions are derived using the polarities of first arrival P-waves recorded at KIGAM, Bmh and KEPRI stations. The result suggest that thrust motion with significant amount of strike slip component is dominant mode of faulting. The larger population of mechanism is characterized by WNW-ESE striking nodal planes. NE-SW direction is interpreted as dominant compressional axis orientation of stress field. These solutions are similar to those of medium size earthquakes studied previously, which is known as typical regional tectonic stress orientation in and around Korean Peninsula.

• 아시안잔디학회지
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• 제4권2호
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• pp.101-118
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• 1990

Effects of Zoysia japonica fired in winter on the arthropoda communities in its grassland and rice field was investigated . The results gave indicated that a significant difference between total 15,120 individuals of 4 classes, 11 orders, 47 families, 92 genera and 103 species in the control of Zoysia japonica grassland, and total 1, 404 individuals of 4 classes, 11 orders, 47 families, 53 genera 65 species in the Zoysia japonica grassland fired in winter. Index of similarity of Zoysia japonica grasslands between Kimpo and Yangsuri areas was 0.51. Dominant species of arthropoda communities in Zysia japonica grasstands in Kimpo and Yangsuri areas were Hypogastnua sp. and Proisotorn sp., respectively. The spiders were 9 families and 27 species at Kimpo, and t2 families. and 44 species at Yangsuri, and their dominant species was Gnathonariurn dentaturn at two areas. Laodelphex striatelus in the Zoysia japonica grassland fired in winter was sampled constantly morning, noon and night, hut Gnatlzonariun dentatum was sampled more frequently in the morning than at night. Damage of the spiders in the Zoysia japonica granssland fired in winter was more severe than that of Laodelphcx striatelus .

• Weed & Turfgrass Science
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• 제4권2호
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• pp.77-84
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• 2015

본 연구는 2014년 4월부터 9월까지 경북지역 13개 시 군의 식량작물(양파, 보리, 마늘, 감자) 재배포장에 발생되는 잡초의 분포와 우점도를 알아보기 위하여 수행되었다. 양파밭은 30과 125종, 마늘밭은 29과 101종, 감자밭은 30과 88종, 보리밭은 27과 108종으로 조사되었다. 잡초종 수에 따른 주요 과(family)는 Table 2와 같다. 양파밭에서는 국화과(Compositae) 33종으로 전체 잡초종에서 26.4%, 마디풀과(Polygonaceae)와 십자화과(Cruciferae) 11종으로 8.8%를 차지하였다. 동계작물 재배지의 주요 5개 과에 대한 초종수와 점유율은 양파밭 73종 58.4%, 마늘밭 58종 57.5%, 감자밭 51종 58.0% 및 보리밭 66종 61.1%로 양파밭, 보리밭, 마늘밭, 감자밭 순으로 초종이 많았고 초종별 점유율은 보리밭에서 61.1%로 가장 높았다. PCA (Principal Community Analysis) 분석에서 보리밭의 벼룩나물, 뚝새풀 및 쇠별꽃은 마늘, 양파 및 감자밭에서 발생되는 초종과 뚜렷한 구별성을 보였다.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2000년도 하계종합학술대회 논문집(2)
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• pp.76-79
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• 2000

The 3$\mu\textrm{m}$-thick PVDF (Polyvinyiidene fluoride) thin film have been prepared using physical vapor deposition with electric field, and its FT-IR specrum, dielectric property and electric conduction phenomenon have been investigated. Since the characteristic peaks ate detected at 509.45 and 1273.6〔cm〕 in the FT-IR spectrum, we are confirmed that the ${\beta}$ -phase is dominant in the PVDF thin film. In the results of dielectric properties, the PVDF thin film shows anomalous dispersion, i.e. gradual decrease of dielectric constant with increase of frequency, and also that the dielectric absorption point changes from 200Hz to 7000Hz with increasing temperature of thin film, which is consistent with the Debye's theory. The activation energy (ΔH) obtained from temperature dependence of dielectric loss is 21.64 ㎉/㏖. We confirm that the electric conduction mechanism of PVDF thin film is dominated by ionic conduction by investigating the dependence of the leakage current of the thin film on the temperature and the electric field.

• The Korean Journal of Ecology
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• 제18권2호
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• pp.275-283
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• 1995

Seral changes in floristic composition during abandoned field succession after shifting cultivation was investigated in eastern Kangwon-Do, Korea. According to the DCA ordination based on the floristic composition, sere of the dominant species was shown as follows: Digitaria sanguinalis, Persicaria spp., Commelina communis etc. in the annual stage (0∼1 years); Erigeron spp., Artemisia spp., Rubus crataegus etc. in the Erigeron-Artemisia stage (2∼6 years); Pinus densiflora, Salix spp., Miscanthus sinensis, Arundinella hirta etc. in the shrub - earlier tree stage (10∼25 years); P. densiflora, Quercus mongolica, Spodiopogon sibiricus etc. in the mid-tree stage (25∼50 years); Q. mongolica, Tripterigium regelii, Lespedeza maximowiczii, Carex siderosticta etc. in the latter tree stage (50∼80 years). In mid-tree stage, size-frequency distribution of P. densiflora was plotted as a platycurtic curve and that of Q. mongolica as a reverse J-shaped curve, which meant P. densiflora was thinned through interspecific competition and Q. mongolica was regenerated by itself in the later tree stage.

• 설비공학논문집
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• 제13권7호
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• pp.595-601
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• 2001

We applied PIV method to obtain instantaneous and ensemble averaged velocity fields from the first row to the fifth row of a staggered tube bundle. The Reynolds number based on the tube diameter and the maximum velocity was set to be 4,000. Remarkably different natures are observed in the developing bundle flow. Such differences are depicted in the mean recirculating bubble length and the vorticity distributions. The jet-like flow seems to be a dominant feature after the second row and usually skew. However, the ensemble averaged fields show symmetric profiles and the flow characteristics between the third and fourth measuring planes are not so different. comparison between the PIV data and the RANS simulation yields severe disagreement in spite of the same Reynolds number. It can be explained that the distinct jet-like unsteady motions are not to be accounted in th steady numerical analysis.