• 한국약용작물학회지
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• 제9권3호
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• pp.232-237
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• 2001

본 연구는 야콘의 광합성 효율증진을 위한 기상환경 조건을 규명하여 재배적지의 선정과 재배관리에 대한 기초적 자료를 제공하고자 광도와 온도, 그리고 $CO_2$의 농도에 대한 광합성과 증산량을 조사하였다. 광 보상점은 ${58\;{\mu}mol\;m^{-2}\;s^{-1}}$이었고, 포화점은 ${1708\;{\mu}mol\;m^{-2}\;s^{-1}}$이었다, 증산량은 광도가 증가할수록 높아져 광도 ${2193\;{\mu}mol\;m^{-2}\;s^{-1}}$에서 약 4 mmol ${m^{-2}\;s^{-1}}$간에 이르렀다. 광합성의 최적온도는 ${24^{\circ}C}$였으며, 온도의 변화에 의하여 증산량이 4 mmol ${m^{-2}\;s^{-1}}$에서 8 mmol ${m^{-2}\;s^{-1}}$까지 증가하였을 때 광합성은 오히려 감소하는 경향이었다. 이산화탄소 보상점은 63 mol mol ${m^{-2}\;s^{-1}}$이었고, 포화점은 1155 vpm이었으며, 이산화탄소 농도가 350vpm에서 1300vpm까지 증가함에 따라 광포화점은 높아졌다.

• 한국약용작물학회지
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• 제10권1호
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• pp.1-4
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• 2002

본 연구는 헛개나무의 광합성 효율증진을 위한 기상환경 조건을 규명하여 재배적지의 선정과 재배관리에 대한 기초적 자료를 제공하고자 광도와 온도, 그리고 $CO_2$의 농도에 대한 광합성과 증산량을 조사하였다. 광 보상점은 $2.4\;{\mu}mol\;m^{-2}\;s^{-1}$이었고, 포화점은 $1033\;{\mu}mol\;m^{-2}\;s^{-1}$이었다. 광도 $100\;{\mu}mol\;m^{-2}\;s^{-1}$에서 광합성의 최적온도는 $25^{\circ}C$이었다. 이산화탄소 보상점은 67 vpm이었고, 포화점은 707 vpm이었다. 증산량은 광도가 $1750\;{\mu}mol\;m^{-2}\;s^{-1}$까지 그리고 온도가 $18^{\circ}C$에서 $36^{\circ}C$까지 높아질수록 $2\;mmol\;m^{-2}\;s^{-1}$와 $4\;mmol\;m^{-2}\;s^{-1}$정도로 각각 증가하였으나 이산화탄소 농도가 21 vpm에서 800 vpm으로 높아질 때는 감소하는 경향이었다.

• 한국산림과학회지
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• 제95권5호
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• pp.614-620
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• 2006

To study the chlorophyll contents and photosynthetic characteristics of 4 tree species of deciduous hardwoods; Betula platyphylla var. japonica, Zelkova serrata, Acer mono and Prunus sargentii were treated in 3 stages of shading; the full sun treatment, the medium shade treatment with 30% of transmittance comparing to full sun, the intense shade treatment with 8% of transmittance and their changes in chlorophyll contents and photosynthetic characteristics were examined and analyzed. Most hardwoods showed differences in the total chlorophyll contents in the order of May < September < July, however, that in Prunus sargentii increased progressively along with the lapse of time. Concerning the degree of shading, total chlorophyll contents increased in proportion to the level of shading. Betula platyphylla var. japonica and Prunus sargentii showed more than 2-3 times difference between the full sun treatment and the intense shade treatment. The changes in photosynthetic characteristics, the range of the light saturation point of the trees was $1,000{\sim}1,100{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$ in May, before the shading was applied, and the intensity was shown in the order of Betula platyphylla var. japonica > Zelkova serrata > Acer mono > Prunus sargentii. The photosynthetic rate was $6.4{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}{\sim}27.1{\mu}mol{\cdot}CO_2{\cdot}m^{-2}{\cdot}s^{-1}$ in the order of Betula platyphylla var. japonica > Prunus sargentii > Acer mono > Zelkova serrata that there were differences between species. Concerning the changes in light saturation point in each growth period after shading treatment, the light saturation point in the full sun treatment was found in the range of $560{\sim}1,100{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$ and the level of intensity was shown in the order of May > July > September. The light saturation point decreased as the level of shading intensified and the level of changes in light compensation point in the full sun treatment for Betula platyphylla var. japonica and Prunus sargentii was shown in the range of $2.9{\sim}27.1{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$ in the order of May > July > September, however, for Zelkova serrata and Acer mono was shown in the range of $3.9{\sim}11.7{\mu}mol{\cdot}CO_2{\cdot}m^{-2}{\cdot}s^{-1}$ in the order of July > May > September that there were differences between species.

• 한국통신학회논문지
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• 제21권1호
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• pp.47-58
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• 1996

An object color can be seen differently under the various outer illuminants. However, human visual system has color constnacy that the object color can be seen constantly under the different outer illuminants. When the viewer watches TV under specific that the object color can be seen constantly under the different outer illuminants. When the viewer bathes TV under specific outer illuminants, he perceives distortes color due to the emitting specturm of outer illuminants as well as the radiation of CPT itself. Namely, when the outer illuminants such as fluorescent and incandescent lamps incident on CPT, brightness, saturation, hue, itself. Namely, when the outer iluminants such as fluorescent and incandescent lamps incident on CPT, brightness, saturation, hue, and contrast on color pictures are changend, he perceives distortedcolr fromthe original color. In this paper color enhancement algorithm based on light intensity and outer light decision funtion using RGB sensor was proposed. The implemented TV of proposed algorithm has higher visual quality at the view point of human visual system and more vivid than that ofcoventional color TV.

• 대한기계학회논문집B
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• 제34권10호
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• pp.947-955
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• 2010

대부분의 석유 가스전은 탄화수소혼합물과 일반기체 등 저류층 내부 유체의 성분조성에 따라 저류층내 상거동 특성이 매우 민감하게 변화한다. 석유 가스전의 평가와 개발 생산계획을 수립함에 있어, 이러한 상거동에 따른 기체와 액체의 성분비 결정과 석유와 가스의 이상유동 해석을 위한 저류유체의 PVT관계 및 포화물성의 규명은 필수적이다. 이중에서 특히, 포화물성의 계산은 수렴성이 나빠, 이상 유동의 해석적 연구에 있어서 많은 어려움을 초래하는 원인이 되고 있다. 이에 본 연구에서는 포화물성 의 계산에 있어서 수렴도 향상을 위한 새로운 초기값 추정 방법과 근 탐색 알고리듬을 제안하고, 성능비교 등을 통한 수렴도 영향인자에 대한 분석을 시도하였다. 결과적으로, 제안된 방법을 통해 포화물성 해석 수렴성을 개선하였고 GUI 기반의 새로운 다성분 다상거동해석 시뮬레이터의 개발에 적용하였다.

• Journal of Crop Science and Biotechnology
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• 제11권1호
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• pp.75-82
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• 2008

Functional stay-green is a beneficial trait that may increase grain yield through the sustained photosynthetic competence during monocarpic senescence in cereal crops. The temporal changes of photosynthesis and related characteristics throughout the grain filling period of a stay-green japonica rice "SNU-SG1" was compared in growth chamber conditions with three high-yielding cultivars(HYVs) and their $F_1$ hybrids with SNU-SG1. SNU-SG1 exhibited a typical characteristic of functional stay-green in terms of chlorophyll degradation and photosynthetic competence during grain filling. According to the photosynthesis-light response curve measured at 10 and 35 d after heading for the flag leaf, SNU-SG1 exhibited higher initial light conversion efficiency and thus higher gross photosynthetic rate at light saturation compared to HYVs. Light saturation point was not different among genotypes, ranging from 1000 to 1500 ${\mu}mol$ photon $m^{-2}s^{-1}$. Net photosynthetic rate at light saturation($P_{max}$) of the upper four leaves in SNU-SG1 was much higher and sustained longer throughout grain-filling than HYVs and $F_1$ hybrids. The sustained high photosynthetic competence of SNU-SG1 during grain filling was ascribed to the longer maintenance of high mesophyll conductance that resulted from not only high chlorophyll content and its delayed degradation but also the slow degeneration of photosystem II(PS II) as judged by chlorophyll fluorescence($F_v/F_m$) of flag leaves. $F_1$ hybrids showed slow degeneration of photosystem II similar to the male parent SNU-SG1 while chlorophyll degradation pattern close to female parents, thus exhibiting a little higher $P_{max}$ than female parents. These results suggest that SNU-SG1 has a typical functional stay-green trait that can be utilized for increasing rice yield potential through the improved dry matter production during grain filling.

• Journal of Ginseng Research
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• 제12권1호
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• pp.87-91
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• 1988

일복개량의 일환으로 일복의 피복재선택을 위한 기초자료를 얻고자 적색광, 청색광 및 백색광하에서 미국인삼(Panax quinquefolin L.)의 광합성을 측정하였다. 광질별 광합성량은 전반적으로 적색과, 백색광 및 청색광 순으로 많았으며 그 광합성량의 차이는 조도가 증가할수록 감소되었다. 따라서 일복의 피복물 색상은 적색으로 하는 것이 인삼(미국인삼) 생육에 유이할 것임을 시사되었다.

• BMB Reports
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• 제40권5호
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• pp.644-648
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• 2007

Exposure of algae or plants to irradiance from above the light saturation point of photosynthesis is known as high light stress. This high light stress induces various responses including photoinhibition of the photosynthetic apparatus. The degree of photoinhibition could be clearly determined by measuring the parameters such as absorption and fluorescence of chromoproteins. In cyanobacteria and red algae, most of the photosystem (PS) II associated light harvesting is performed by a membrane attached complex called the phycobilisome (PBS). The effects of high intensity light (1000-4000 ${\mu}mol$ photons $m^{-2}s^{-1}$) on excitation energy transfer from PBSs to PS II in a cyanobacterium Spirulina platensis were studied by measuring room temperature PC fluorescence emission spectra. High light (3000 ${\mu}mol$ photons $m^{-2}s^{-1}$) stress had a significant effect on PC fluorescence emission spectra. On the other hand, light stress induced an increase in the ratio of PC fluorescence intensity of PBS indicating that light stress inhibits excitation energy transfer from PBS to PS II. The high light treatment to 3000 ${\mu}mol$ photons $m^{-2}s^{-1}$ caused disappearance of 31.5 kDa linker polypeptide which is known to link PC discs together. In addition we observed the similar decrease in the other polypeptide contents. Our data concludes that the Spirulina cells upon light treatment causes alterations in the phycobiliproteins (PBPs) and affects the energy transfer process within the PBSs.

• 한국토양비료학회지
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• 제14권4호
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• pp.224-229
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• 1982

울릉도자생(鬱陵島自生) 섬바디의 광합성(光合成) 및 호흡(呼吸)에 대(對)한 광도(光度) 및 온도(溫度)의 영향(影響)을 조사(調査)하였다. 1. 광합성(光合成)의 광포화점(光飽和点) 및 광보상점(光補償点)은 $20^{\circ}C$에서 각각(各各) 34~38klux와 4~6klux이고 광포화점(光飽和点)에서의 광합성속도(光合成速度)(호흡량(呼吸量)을 제(除)한)는 9~12mg $CO_2/dm^2/hr.$이었다. 2. 광합성적온(光合成適溫)은 $20^{\circ}C$이고 2온도범위($20{\sim}30^{\circ}C$, $30^{\circ}C{\sim}400^{\circ}C$)에서 광합성(光合成)의 $Q_{10}$치(値)는 0.8 및 0.9이고 호흡(呼吸)의 $Q_{10}$치(値)는 1.6 및 1.7이었다. 3. 자생지(自生地)의 환경조건(環境條件)에 적응(適應)하여 해발고도(海拔高度)가 높은 장소(場所)에서 자생(自生)한 식물본의 광보상점(光補償点)이 낮았다. 이상(以上)의 결과는 우리나라의 본과 가을이 섬바디생육(生育)에 적합(適合)함을 알 수 있고 하절기(夏節期)의 생육(生育)이 저조할 것임으로 다른 목초(牧草)와의 혼식재배(混植栽培)가 이상적(理想的)이라고 생각된다.

• Journal of Ginseng Research
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• 제36권4호
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• pp.461-468
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• 2012

In this study, photosynthetic parameters such as the net photosynthesis rate, stomatal conductance, intercellular $CO_2$ concentration, and transpiration rate were examined in selected ginseng varieties and/or lines that are resistant (Yunpoong, HTIR 1, HTIR 2, and HTIR 3) and susceptible (Chunpoong) to high temperature injury (HTI). The net photosynthesis rate increased with the increase in the light intensity in all the HTI-resistant and -susceptible ginseng lines with a light saturation point of $200\;{\mu}mol\;m^{-2}s^{-1}$, except for Yunpoong that had a light saturation point of $400\;{\mu}mol\;m^{-2}s^{-1}$. At the light saturation point, the net photosynthesis rate in July was highest in HTIR 3, at $4.2\;{\mu}mol\;CO_2\;m^{-2}s^{-1}$, and was lowest in Yunpoong, HTIR 1, Chunpoong, and HTIR 2, in that order, at 1.9 to $3.7\;{\mu}mol\;CO_2\;m^{-2}s^{-1}$. The net photosynthesis rate in August was highest in Yunpoong at $5.9\;{\mu}mol\;CO_2\;m^{-2}s^{-1}$, and lowest in HTIR 1 and HTIR 3 ($4.5\;{\mu}mol\;CO_2\;m^{-2}s^{-1}$) and in other lines, in that order, at 2.8 to $2.9\;{\mu}mol\;CO_2\;m^{-2}s^{-1}$. The stomatal conductance in July was highest in HTIR 3 (0.055 mol $H_2O\;m^{-2}s^{-1}$) and Yunpoong, Chunpoong, HTIR 1, and HTIR 2 were 0.038, 0.037, 0.031, and 0.017 in that orders. In August, meanwhile, HTIR 1 showed the highest as 0.075, and followed by HTIR 3, Chungpoong, and HTIR 2 with 0.070, 0.047, and 0.023, respectively. The intercellular $CO_2$ concentration at the light saturation point in July and August was much lower in HTIR 2 at 139 and $185\;{\mu}mol\;mol^{-1}$ than in the other ginseng lines at 217 to 257 and 274 to $287\;{\mu}mol\;mol^{-1}$, respectively. The transpiration rate in July and August was higher in the HTI-resistant lines of Yunpoong, HTIR 1, and/or HTIR 3 at 0.83 to 1.03 and 1.67 to 2.10 mol $H_2O\;m^{-2}s^{-1}$ than in the other ginseng lines at 0.27 to 0.79 mol $H_2O\;m^{-2}s^{-1}$ and 0.51-1.65 mol $H_2O\;m^{-2}s^{-1}$, respectively. Conclusively, all the photosynthetic parameters that were examined in this study were generally higher in the HTI-resistant ginseng lines than in the HTI-susceptible lines, except for HTIR 2, and were much higher in August than in July, especially in the resistant ginseng lines. All these results can be used to provide basic information for the selection of HTI-resistant ginseng lines and the application of cultural practices that are efficient for ginseng growth, based on the photosynthetic characteristics of the lines.