• Asian-Australasian Journal of Animal Sciences
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• 제19권7호
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• pp.970-977
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• 2006

Forage oat (Avena sativa L.) is grown extensively in a double-cropping system on dairy farms. Four oat varieties ('Swan', 'Targa', 'Foothill', and 'Nugene') were evaluated for forage production and forage quality during two growing seasons (spring and autumn) at two locations (central and southern region) in South Korea. The heading stage of four oat varieties was observed during spring, but the autumn season did not produce heading until harvest time except for the 'Swan' variety (early-maturing variety). The heading stage of 'Swan' in both locations was earlier compared to other varieties. The four varieties were resistant to both foliar disease and insects. Lodging resistance was higher during autumn except in 2002 at the central region, and late-maturing varieties ('Foothill' and 'Nugene') have lower lodging resistance. Dry matter (DM) content was significantly different between varieties (p<0.001). Comparing different varieties, 'Swan', an early-maturing variety, was highest in DM content. In DM, total digestible nutrients (TDN) and crude protein (CP) yield, the yield of oat varieties in the southern region was higher than in the central region, and forage yield of the oat varieties in the spring season was higher than during the autumn season. The DM and TDN yield showed significant differences between oat varieties. The CP content of oats grown in the central region (Cheonan) was lower than oats grown in the southern region (Daegu), and the spring season produced oats with lower CP compared to the autumn season. Among the four oat varieties, the CP content of late-maturing varieties was higher than the Swan variety (early-maturing variety). The acid detergent fiber (ADF) and neutral detergent fiber (NDF) contents were higher for the varieties grown in Cheonan and during the spring season. The ADF and NDF contents of late-maturing varieties were lower than the early-maturing variety. TDN and relative feed value (RFV) were higher for the varieties grown in Daegu and during the autumn season. Late-maturing variety had higher TDN and RFV than early-maturing variety. Our study showed differences in forage production and forage quality of oats grown in different locations, seasons and varieties. Forage quality as well as forage production was better in the southern region than in the central region. Forage quality was better during autumn, but forage production was better during spring. Late-maturing variety had better forage quality than the early-maturing variety. Therefore, late-maturing varieties are more suitable for use in the southern region.

• 문화기술의 융합
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• 제8권1호
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• pp.209-218
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• 2022

본 연구는 근대문화유산관련 호텔을 연구하기 위하여 첫째, 문헌분석을 통한 역사적 접근을 시도하여 근대호텔 발전사를 정립하였다. 둘째, 대불호텔 복원관련 자료와 관계자의 인터뷰를 통해 관광산업적 활용사례를 조사하여 관광산업적 활용방안을 제시하고자 하였다. 근대호텔 복원을 위한 관광산업적 활성화 방안을 제시하면 첫째, 각 지역의 근대문화유산의 근대호텔 복원계획은 철저한 당위성 검토와 콘텐츠 개발계획으로 이루어져야 한다. 둘째, 각 지역의 근대호텔 복원은 지자체의 행정적 관리체계 구축과 의지가 있어야 한다. 셋째, 근대호텔 복원은 역사적 의미와 가치가 있는 것으로 각 지역의 관광활성화 기여 및 경제적 효과, 고용촉진 등에 기여할 수 있는 사업으로 추진되어야 한다. 넷째, 근대호텔 복원에 대한 지속적·적극적 홍보 수단 마련이 필요하다.

• 천문학회보
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• 제39권1호
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• pp.84.1-84.1
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• 2014

We report the spatial distribution of early-type stars and pre-main-sequence (PMS) stars around the starburst type young open cluster Westerlund 2. The early-type were selected from UBVI photometric data, while the PMS members were identified from their X-ray emission and mid-infrared excess. The northern clump of the cluster is composed mainly of PMS stars detected in both optical and X-ray and seems to be coeval to the cluster, while PMS stars in the bright bridge region are highly obscured in optical wavelength. The bright bridge appear to be an on-going star forming region possibly triggered by the strong radiation field from both sides-massive stars in Westerlund 2 and WR 20b. We also found that there are many early-type stars not only in the cluster but also farther from the cluster up to several times of the cluster radius. These early-type stars are well aligned from east to southwest of the cluster. We conclude these early-type stars are members of an OB association in the RCW 49 nebula. This report indicates there is a complex star formation history in Westerlund 2 and its surrounding H II region, the RCW 49 nebula.

• 대한기계학회논문집B
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• 제30권5호
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• pp.465-471
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• 2006

Controlled auto-ignition(CAI) combustion, offers the potential to improve fuel economy and reduce emission simultaneously. In this study, CAI-combustion was achieved in a single cylinder gasoline DI engine with modified camshafts in order to restrict the gas exchange process. We investigated the effects of air-fuel ratio, residual EGR rate and injection timing such as early injection and late injection on the attainable CAI combustion region. The effect of injection timings on combustion characteristic such as start of combustion, combustion duration and heat release rate was also investigated. From the result early injection causes the mixture to ignite earlier and burn more quickly due to the exothermic reaction during the recompression and gives rise to good mixing of the fuel/air. On the other hand, late injection extended the operation region more than early injection but the emissions of HC and NOx were more or less increased than early injection.

• Journal of Plant Biology
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• 제36권1호
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• pp.29-34
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• 1993

Observation was made on early ontogeny of vascular cambium in the cotyledonary node of Pinus koraiensis seedling in order to clarify the cambial ontogeny of the node which was hardly elongated. In transverse view, the derivatives by the early periclinal divisions at the outer region of the procambial strands differentiated to protophloem with establishing a certain degree of radial seriations. Later, some cells in the central region of the procambial strands begin divide periclinally, eventually the cells, differentiate gradually to the vascular cambium. In tangential view, early procambium is consisted of homogeneous short cells with transverse end walls which are tansformed into the long cells and short cells gradually. The long cells continue intrusive growth and the short cells repeat transverse division. Finally, the long and short cells differentiated to cambial fusiform initials and ray initials respectively. In tangential section, the differentiation pattern of cambial initials resembles that of the stem of Ginkgo biloba. But in transverse view, the characteristics in the origin of vascular cambium of the cotyledonary node resembles that of root. The vascular cambium in cotyledonary node is completed after eleven prophylls were formed.

• Journal of electromagnetic engineering and science
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• 제18권3호
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• pp.206-211
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• 2018

In this paper, we proposed a two-level feature vector fusion technique to improve the performance of target classification. The proposed method combines feature vectors of the early-time region and late-time region in the first-level fusion. In the second-level fusion, we combine the monostatic and bistatic features obtained in the first level. The radar cross section (RCS) of the 3D full-scale model is obtained using the electromagnetic analysis tool FEKO, and then, the feature vector of the target is extracted from it. The feature vector based on the waveform structure is used as the feature vector of the early-time region, while the resonance frequency extracted using the evolutionary programming-based CLEAN algorithm is used as the feature vector of the late-time region. The study results show that the two-level fusion method is better than the one-level fusion method.

• 한국화재소방학회:학술대회논문집
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• 한국화재소방학회 2008년도 춘계학술논문발표회 논문집
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• pp.135-138
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• 2008

Many Victims and property damage are caused in fires. In this paper, an flame detection algorithm is proposed to early alarm fires. The proposed flame detection algorithm is based on 2-stage decision strategy of video processing. The first decision is to check with color distribution of input vidoe. In the second, the candidated region is settled as fire region with activity. As a result of simulation, it is shown that the proposed algorithm is useful for fire recognition.

• 한국응용곤충학회지
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• 제46권1호
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• pp.27-35
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• 2007

영남지방의 지역 및 기후지대별 담배거세미나방과 파밤나방의 발생소장을 각각의 성페로몬을 이용하여 조사하였다. 경람지역에서 담배거세미나방은 3월 중하순부터 11월 중하순까지 발생하였다. 경북지역에서 담배거세미나방은 4월 중하순부터 11월 상중순까지 발생하였으나, 울진에선 5월 하순부터 10월 하순까지 발생하였다. 기후지대별 담배거세미나방의 발생최성기는 남부해안지대에서 9월 중순, 내륙지대 및 분지지대에서 8월 하순, 내륙산간지대에서 8월 중순, 그리고 동해안중부지대에서 9월 상순이었다. 담배거세미나방의 지역별 발생비율은 경남의 경우 진주에서 20.0%로 가장 높았으며, 창녕에서 8.6%로 가장 낮았고, 경북의 경우 성주에서 3.3%로 가장 높았으며, 울진에서 0.8%로 가장 낮았다. 기후지대별 발생비율은 내륙지대에서 43.7%로 가장 높았으며, 다음은 남부해안지대에서 36.3%, 분지지대에서 8.4%, 내륙산간지대에서 7.0%이었고, 동해안중부지대에서 4.6%로 가장 낮았다. 한편, 파밤나방은 경북의 동해안중부지대를 제외하곤 3월 상순부터 11월 중순까지 발생하였다. 포항, 영덕 및 울진의 동해안중부지대에서 파밤나방은 대체로 4월 중순부터 11월 중순까지 발생하였다. 기후지 대별 파밤나방의 발생최성기는 내륙지대, 분지지대 및 내륙산간지대에서 8월 상순, 남부해안지대 및 동해안중부지대에서 8월 하순이었다. 파밤나방의 지역별 발생비율은 경남의 경우 창녕에서 1.6%로 가장 높았으며, 부산에서 0.4%로 가장 낮았고, 경북의 경우 성주에서 37.2%로 가장 높았으며, 울진에서 2.7%로 가장 낮았다. 기후지대별 발생비율은 분지지대에서 약 54.3%로 가장 많았으며, 다음은 내륙산간지대에서 29.9%, 동해안중부지대에서 9.3%, 내륙지대에서 3.9%이었고, 남부해안지대에서 2.6%로 가장 낮았다. 따라서 담배거세미나방은 경남지방에서, 파밤나방은 경북지방에서 다발생 되었고, 기후지대별 담배거세미나방의 발생량은 경남의 내륙지대, 파밤나방의 발생량은 경북의 분지지대에서 가장 많았다. 영남지방에서 담배거세미나방의 발생량은 파밤나방보다 2.4배 많았으나, 최초 발생시기와 발생최성기는 담배거세 미나방보다 파밤나방이 약간 빨랐다.

• Journal of Advanced Marine Engineering and Technology
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• 제25권6호
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• pp.1228-1236
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• 2001

In this study, CT specimens were prepared from ASTH A5l6 steel which was used for pressure vessel plates for moderate and lower temperature service. And we got the fellowing characteristics from fatigue crack growth test carried out in the environment of room and low temperature at $25^{\circ}C$ , $-30^{\circ}C$, $-60^{\circ}C$, $-80^{\circ}C$, $-100^{\circ}C$ and $-120^{\circ}C$ and in the range of stress ratio of 0.1, 0.3 by means of opening mode displacement. At the constant stress ratio, the Threshold stress intensity factor range ΔAKth in the early stage of fatigue crack growth (Region I) and stress intensity factor range $\DeltaK$ in the stable of fatigue crack growth (Region II) was increased in proportion to descend temperature. It assumed that the fatigue resistance characteristics and fracture strength at low temperature is considerable higher than that of room temperature in the early stage and stable of fatigue crack growth region. The straight line slope relation of logarithm da/dN-$\Delta$K in Region II that is, the fatigue clack growth exponent m increased with descending temperature at the constant stress ratio. It assumed that the fatigue crack growth rate da/dN is rapid in proportion to descend temperature in Region II and the cryogenic-brittleness greatly affect a material with decreasing temperature.

• 한국해양공학회지
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• 제14권3호
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• pp.78-83
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• 2000

In this study, CT specimens were prepared from AST SA516 Gr. 70 which was used for pressure vessel plates for room and low temperature service. And we got the following characteristics from fatigue crack growth test carried out in the environment of room and low temperature at 25$^{\circ}C $, -60$^{\circ}C $, -80$^{\circ}C $ and -100$^{\circ}C $ and in the range of stress ratio of 0.05, 0.3 by means of opening mode displacement. At the constant stress ratio, the threshold stress intensity factor range ${\delta} K_{th}$ in the early stage of fatigue crack growth (Region I) and stress intensity factor range $\delta $K in the stable of fatigue crack growth (Region II) were increased in proportion to descending temperature. It was assumed that the fatigue resistance characteristics and fracture strength at low temperature is considerable higher than that of room temperature in the early stage and stable of fatigue crack growth region. The straight line slope relation of logarithm da/dN -$\delta $K in Region II, that is, the fatigue crack growth exponent m increased with descending temperature at the constant stress ratio. It was assumed that the fatigue crack growth rate da/dN is rapid in proportion to descending temperature in Region II and the cryogenic-brittleness greatly affect a material with decreasing temperature.