• 천문학회보
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• 제43권1호
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• pp.34.2-35
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• 2018

Galaxy transition from star-forming to quiescent, accompanied with morphology transformation, is one of the key unresolved issues in extragalactic astronomy. Although several environmental mechanisms have been proposed, a deeper understanding of the impact of environment on galaxy transition still requires much exploration. My Ph.D. thesis focuses on which environmental mechanisms are primarily responsible for galaxy transition in different environments and looks at what happens during the transition phase using multi-wavelength photometric/spectroscopic data, from UV to mid-infrared (MIR), derived from several large surveys (GALEX, SDSS, and WISE) and our GMOS-North IFU observations. Our multi-wavelength approach provides new insights into the *late* stages of galaxy transition with a definition of the MIR green valley different from the optical green valley. I will present highlights from three areas in my thesis. First, through an in-depth study of environmental dependence of various properties of galaxies in a nearby supercluster A2199 (Lee et al. 2015), we found that the star formation of galaxies is quenched before the galaxies enter the MIR green valley, which is driven mainly by strangulation. Then, the morphological transformation from late- to early-type galaxies occurs in the MIR green valley. The main environmental mechanisms for the morphological transformation are galaxy-galaxy mergers and interactions that are likely to happen in high-density regions such as galaxy groups/clusters. After the transformation, early-type MIR green valley galaxies keep the memory of their last star formation for several Gyr until they move on to the next stage for completely quiescent galaxies. Second, compact groups (CGs) of galaxies are the most favorable environments for galaxy interactions. We studied MIR properties of galaxies in CGs and their environmental dependence (Lee et al. 2017), using a sample of 670 CGs identified using a friends-of-friends algorithms. We found that MIR [3.4]-[12] colors of CG galaxies are, on average, bluer than those of cluster galaxies. As CGs are located in denser regions, they tend to have larger early-type galaxy fractions and bluer MIR color galaxies. These trends can also be seen for neighboring galaxies around CGs. However, CG members always have larger early-type fractions and bluer MIR colors than their neighboring galaxies. These results suggest that galaxy evolution is faster in CGs than in other environments and that CGs are likely to be the best place for pre-processing. Third, post-starburst galaxies (PSBs) are an ideal laboratory to investigate the details of the transition phase. Their spectra reveal a phase of vigorous star formation activity, which is abruptly ended within the last 1 Gyr. Numerical simulations predict that the starburst, and thus the current A-type stellar population, should be localized within the galaxy's center (< kpc). Yet our GMOS IFU observations show otherwise; all five PSBs in our sample have Hdelta absorption line profiles that extend well beyond the central kpc. Most interestingly, we found a negative correlation between the Hdelta gradient slopes and the fractions of the stellar mass produced during the starburst, suggesting that stronger starbursts are more centrally-concentrated. I will discuss the results in relation with the origin of PSBs.

• 아시안잔디학회지
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• 제1권1호
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• pp.7-17
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• 1987

The experiment with two levels of nitrogen (0. and 300kg / ha / year) and two levels of clipping height (1.5cm and 4cm) was conducted on the field during the period 3 June to 23 October 1985. Clonal lines of korean lawngrass ( Zoysia japonica Steud.) and manilagrass ( Zoysia matrella ( L.) Merr.)of Daejon origin were established in June, as individual clone in rows 30cm apart with a 40cm spacing between clones, actually 4 clones each plot. The results obtained were as follows : 1. When no nitrogen was applied to korean lawngrass, leaf blade which appeared during the August / early September period remained green for a period of about 10 weeks and even leaves emerged in late September lived for 42 days. However, leaf longevity did not exceed 8 weeks as nitrogen was applied. In contrast the leaf longevity of manilagrass which emerged during the mid - August / early September period was 11 weeks and, under the nitrogen applied, 9 weeks, indicating that the life - saen of individual leaf of manilagrass may be longer than that of korean lawngrass. Meanwhile, clipping height had no effect on the leaf longevity in both grasses. 2. During the July / August period, tiller number, green leaf number and DM weight of korean lawngrass were increased significantly with fertilizer nitrogen, but were not with two levels of clipping height. This trend was reversed after late September : no effect of nitrogen was appeared. Instead, lax clipping increased tiller number, green leaf number and DM weight. Green leaves stimulated by lax clipping resulted in the occurrance of more dead leaves in late October. 3. The increase of tiller number, green leaf number, and DM weight of korean lawngrass due to nitrogen application appeared to be of significance in early September. Unlike korean lawngrass, however, this significant increase was maintained to late October when new green leaves still emerge. Clipping height had little effect on the growth of manilagrass by early September, but since then, lax clipping stimulated leaf appearance, possibly resulting in a remained green color of manilagrass turf. 4. Among the stolons outgrown until early September, the primary stolon was not influenced by nitrogen and clipping treatments to produce only 2 - 3 stolons. However, 1st branch stolon as affected by nitrogen increased significantly, so most of stolons which occurred consisted of 1st branch stolon. 5. Until early September, stolon length obtained at nil nitrogen level was chiefly caused by lengthening the primary stolons. By applying nitrogen the primary stolons of korean lawngrass was longer than 1st branch stolons when severe clipping was involved and in turn, shorter than 1st branch stolons when lax clipping was concerned. In manilagrass, 1st branch stolons were much longer than the primary stolons when turf was clipped severely but in conditions of lax clipping, there was little difference in length between primary and 1st branch stolons. 6. Stolon nodes of both korean lawngrass and manilagrass were positively influenced by nitrogen, but no particular increases by imposing clipping height treatment was marked in manilagrass. Although the stolon of korean lawngrass was grown until late october, the growth stimulated by nitrogen was not so remarkable as to exceed that a by nil N. 7. The thickness of korean lawngrass and manilagrass was greatest in late September, but that of manilagrass did not differ significantly from that in late October. 8. The response of stolon length of korean lawngrass to lax clippings was not so great in late October as to that to severe clippings. On the other hand, the positive effect of lax clippings to stolon length in m anilagrass was confirmed even in late October.

• 생태와환경
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• 제34권2호통권94호
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• pp.81-89
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• 2001

녹색 유글레나조류와 수환경 요인과의 상호 관계를 규명하기 위하여, 전주시내 도심 하천에서 1996년 9월부터 1997년 8월가지 유글레나조류의 종조성과 밀도 및 환경요인을 매월 조사하였다. 질산염 농도는 6월에 3.22 mg/l로 높았고, 인산염은 겨울철에 0.71 mg/1 이상으로 높았다. 녹색 유글레나조류는 5속 71종이 출현하였으며, 봄에서 초여름 사이에 35${\sim}$42종으로 높고, 겨울에는 20종 이하였다. 출현종 수는 수온과는 정의 상관관계를 보여주었다. 녹색 유글레나조류의 밀도는 겨울과 초여름에 각각 최대가 되는 전형적인 bimodal형을 보여주었다. 겨울의 밀도는 5,394 ce11s/ml로, Euglena caudata, E. geniclata와 E. viridis의 활발한 생장에 기인하였으며, 인산염에 정의 상관관계를 보였다. 초여름의 밀도는 4,823 cells/ml로 E. deses, Lepocinclis ovum과 Phacus trypanon등의 활발한 생장에 기인하며, 암모늄염과 질산염에 정의 상관을 보였다. 녹색 유글레나조류의 생태적 특징은 전주천과 같이 오염된 수계에서 환경요인의 변화를 예측하는 생물학적 자료로 활용할 수 있다.

• 한국유기농업학회지
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• 제23권2호
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• pp.281-289
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• 2015

In sustainable viticulture, green manure represents a safe and non-polluting way to bring large quantities of organic matter into the soil. The cultivation of green manure crops plays an important role in soil quality and sustainability of agricultural system. This study was conducted to evaluate the effects of green manure fertilization on yield and quality of the Campbell Early grape variety in the organic vineyard. Hairy vetch was the more productive green manure crop, yielding higher dry materials. Average yields of grape were significantly greater in hairy vetch+rye ($13.02ton\;ha^{-1}$) than nature weed ($11.65ton\;ha^{-1}$), respectively. The concentrations of total as well as individual anthocyanins were consistently higher with hairy vetch treatment compared with rye and nature weed, thus making the green manure cultivation is an environmentally friendly cultivation to increase the yield and anthocyanin contents in organic grape.

• 생물환경조절학회지
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• 제17권4호
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• pp.293-296
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• 2008

제주에서 무가온 하우스 재배에 적합한 아티초크 품종을 선발코자 'Purple Romagna', 'Imperial Star', 'Green Globe', 'Emerald', 'Italian', 'Carciofo Di Romagna' 품종을 시험재료로 이용하였다. 2004년 10월 5일에 본엽 4매 정도 자란 묘를 무가온 하우스내에 정식하였다. 첫 수확은 이듬해 봄 4월 하순경부터 시작되었는데 첫 수확일은 'Emerald'와 'Imperial Star'가 4월 26일과 27일로 빨랐으며, 대체로 수확은 5월 상순경부터 시작되어 6월 하순까지 가능하였다. 주당 수확 화뢰수는 'Green Globe'가 5.4개 이상으로 가장 많았으며 'Italian께서 1.3개 정도로 가장 적었다. 평균 화뢰무게는 'Imperial Star', 'Green Globe', 'Purple Romagna'에서 $228{\sim}288g$ 정도로 비슷하였다. 10a당 수량은 'Green Globe께서 2,172kg으로 가장 많았으며, 다음이 'Imperial Star'에서 1,947kg이었다. 따라서 난지지역인 제주도에서 아티초크의 무가온 하우스재배에는 수량면에서 'Green Globe'및 'Imperial Star'가 적합할 것으로 판단되며, 10월에 정식하여 재배할 경우 이듬해 4월 하순부터 6월까지 수확할 수 있다.

• 한국수정란이식학회지
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• 제14권1호
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• pp.1-8
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• 1999

The efficiency of transgenic livestock animal production may be improved by early selection of transgenci preimplantation embryos. To examine the possibility of GFP gene as a non-invasive marker for the early screening of transgenic embryo, the GFP gene was microinjected into rabbit zygotes and the later stages of preimplantation embryos were examined for the expression of GFP. The presence of injected DNA was detected by PCR analysis and the expression of GFP was detected by observing green fluorescence in embryos under a fluorescent microscope. Out of 108 GFP gene-injected rabbit zygotes, seventy three(67.6%) were fluorescence-positive. When 11 fluroresecence-positive blastocysts were analyzed for the presence of GFP gene by PCR, 6(54.5%) were positive, and all of the 8 flrouescence-negative blastocysts were also negative by PCR. The results indicate that the screening of transgene in rabbit embryos by PCR analysis and GFP detection could be a promising method for the preselection of transgenic embryos.

• 한국응용곤충학회지
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• 제50권2호
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• pp.167-170
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• 2011

쌍줄푸른밤나방(Pseudoips fagana Fabricius)은 분류학적으로 밤나방과(Noctuidae), 푸른밤나방아과(Chloephorinae)에 속한다. 쌍줄푸른밤나방의 알은 백색이며 참나무잎에 무더기로 산란하였다. 유충은 총 5령기를 거치며, 몸전체에 걸쳐 연녹색을 띠며, 4개의 백색선이 복부의 끝까지 연결되어 있다. 유충기간은 약 24.4일이 소요되었다. 번데기는 연녹색의 단단한 막과 실크로 덮여져 있다. 성충의 날개를 편 길이는 15-18 mm 였으며, 앞날개의 바탕색은 연두색이다. 뒷날개의 경우 수컷은 황색이며 암컷은 백색을 띈다. 쌍줄푸른밤나방의 1화기는 5월 초순부터 6월 말까지이며, 2화기는 7월 초부터 8월 말까지 였으며, 번데기로 월동하였다.

• 한국초지조사료학회지
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• 제27권4호
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• pp.249-256
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• 2007

본 연구는 2005년과 2006년 축산과학원 2개 지역의 시험포장에서 각각 수행되었다. 1년차는 수원(중부)과 남원(남부)에서 2년차는 천안(중부)과 남원(남부)에서 수행되었으며 공시 품종은 헤어리 베치 11품종 도입품종 9품종(Penn-02, Sander, Latigo, Welta, Ostsaat, VV4712, Minnie, Barlosa 및 Capello), 국내품종 2품종(Cold green과 Cheong pa)를 이용하였다. 시험에 사용된 품종을 개화시기를 기준으로 평가한 결과 도입품종 Minnie, Barlosa, Capello 및 국내 품종 Cold green이 조생종이었고, 도입 품종 Penn-02, Sander, Latigo, Welta, Ostsaat, VV4712 및 국내품종 Cheong pa는 중만생종에 속하였다. 월동상태는 조생종 Minnie, Barlosa 및 Capello를 제외하고 대부분 우수하였다. 2년간 시험한 결과 11개 품종중 VV4712가 가장 수량이 높은 품종이었다. 그리고 중부지방에서는 중만생종의 수량이 남부지방에서는 조생종의 수량이 많았다. 두 지역에서 국내 육성품종인 중만생종 Cheong pa는 도입품종들에 비하여 뒤떨어지지 않았고 조생종 Cold green은 도입 품종들에 비하여 생육과 수량이 우수하였다. 헤어리 베치의 NDF, ADF, IVDMD 및 CP 등 사료가치는 조생종보다 중만생종이 좋았고, 그 중에서 NDF는 중만생종 Latigo, ADF는 중만생종 Welta, 소화율과 조단백질 함량은 중만생종 Sander가 가장 좋았다. 이 시험의 결과 헤어리 베치중 VV4712 품종의 생산성이 가장 높았고 국내 육성품종인 Cheong pa와 Cold green은 유망한 품종으로 판단된다.

• 대한토목학회논문집
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• 제35권4호
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• pp.897-905
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• 2015

본 연구에서는 충격파 모형을 이용하여 능동식 우선신호의 최적 신호시간을 산정하기 위한 모형을 제시하였다. 본 신호 최적화 모형을 이용하여 능동형 우선신호 기법 중 Early green 및 Green extension이 적용되는 조건에서 충격파 면적을 산정할 수 있다. 본 연구에서는 평균통행시간 및 교차로 진출시각을 이용해 충격파의 발생 속도를 산정하기 위한 방법을 제시하였으며, 이를 이용해 우선신호로 인한 현시 변화량에 따라 충격파 면적 변화량을 산정할 수 있다. 또한 교차로 전체의 충격파 면적이 최소화되는 신호시간을 산정하여 우선신호로 인해 증가하는 일반차량의 지체를 최소화할 수 있도록 하였다. 우선신호 신호시간 산정 모형의 효과평가를 위해 VISSIM과 ComInterface를 이용한 미시적 시뮬레이션 분석을 시행하였으며, 이동류의 포화상태를 고려하여 지체 최소화를 위한 신호시간이 산정됨을 확인하였다. 독립교차로를 대상으로 하는 사례분석에서 우선신호를 위해 비우선현시를 균일하게 단축하는 전략 대비 본 모형에서 일반차량 지체가 10% 이상 개선됨을 확인하였다. 본 연구는 트램, BRT, 중앙버스 전용차로 등 대중교통 우선시설이 확산되고 있는 최근 국내 상황에서 신호교차로의 운영효율을 높이기 위한 새로운 우선신호 제어 방법을 제시하였다는데 의의가 있겠다.

• JSTS:Journal of Semiconductor Technology and Science
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• 제6권4호
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• pp.270-274
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• 2006

A color filter array (CFA) helps a single electrical image sensor to recognize color images. The Red-Green-Blue (RGB) Bayer CFA is commonly used, but the amount of the light which arrives at the photodiode is attenuated with this CFA. Red-White-Blue (RWB) CFA increases the amount of the light which arrives at photodiode by using White (W) pixels instead of Green (G) pixels. However, white pixels are saturated earlier than red and blue pixels. The pseudo multiple capture scheme and the corresponding RWB CFA were proposed to overcome the early saturation problem of W pixels. The prototype CMOS image sensor (CIS) was fabricated with $0.35-{\mu}m$ CMOS process. The proposed CIS solves the early saturation problem of W pixels and increases the dynamic range.