• 한국작물학회지
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• 제48권4호
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• pp.326-333
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• 2003

Transgenic rice plants expressing a Bacillus subtilis protoporphyrinogen oxidase (Protox), the last shared enzyme of the porphyrin pathway in the expressed cytoplasm or the plastids, were compared with non-trangenic rice plants in their growth characteristics such as tiller number, plant height, biomass, and yield. Transgenic rice plants of $\textrm{T}_3$ generation had 8 to 15 % and 25 to 43% increases in tiller number compared to non-transgenic rice plants at 4 and 8 weeks after transplanting(WAT); similar values were observed for $\textrm{T}_4$ generation at 4 and 8 WAT. However, the plant height in both $\textrm{T}_3$ and $\textrm{T}_4$ generations was similar between transgenic rice plants and non-transgenic rice plants at 4 and 8 WAT. Transgenic rice plants had 13 to 32% increase in above-ground biomass and 9 to 28% increase in grain yield compared to non-transgenic rice plants, demonstrating that biomass and yield correlate with each other. The increased grain yield of the transgenic rice plants was closely associated with the increased panicle number per plant. The percent of filled grain, thousand grains and spikelet number per panicle were similar between transgenic and non-transgenic rice plants. Generally, the growth and yield of transgenic generations ($\textrm{T}_2$, $\textrm{T}_3$, and $\textrm{T}_4$) and gene expressing sites (cytoplasm-expressed and plastid-targeted transgenic rice plants) were similar, although they slightly varied with generations as well as with gene expressing sites. The transgenic rice plants had promotive effects, indicating that regulation of the porphyrin pathway by expression of B. subtilis Protox in rice influences plant growth and yield.

• 한국농공학회논문집
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• 제59권1호
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• pp.71-79
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• 2017

Climate change phenomenon is posing a serious threat to sustainable corn production in Ghana. This study investigated the impacts of climate change on the rain-fed corn yield in the Dangme East district, Ghana by using Aquacrop model with a daily weather data set of 22-year from 1992 to 2013. Analysis of the weather data showed that the area is facing a warming trend as the numbers of years hotter and drier than the normal seemed to be increasing. Aquacrop model was assessed using the limited observed data to verify model's sufficiency, and showed credible results of $R^2$ and Nash-Sutcliffe efficiency (NSE). In order to simulate the corn yield response to climate variability four climate change scenarios were designed by varying long-term average temperature in the range of ${\pm}1^{\circ}C{\sim}{\pm}3^{\circ}C$ and average annual rainfall to ${\pm}5%{\sim}{\pm}30%$, respectively. Generally, the corn yield was negatively correlated to temperature rise and rainfall reduction. Rainfall variations showed more prominent impacts on the corn yield than that of temperature variations. The reduction in average rainfall would instantly limit the crop growth rate and the corn yield irrespective of the temperature variations.

• 한국초지조사료학회지
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• 제39권2호
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• pp.75-80
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• 2019

Oilseed rape is known to crop having low nitrogen use efficiency (NUE) but requires high levels of N fertilizer. NUE is associated with N remobilization from source to sink organ, consequently affects seed yield. Remobilization of leaf N is also related to transport of C/N metabolites in phloem. However, interaction between seed yield and phloem transport was not fully documented. In response to seed yield, N and C metabolites and their transport into seed from bolting to pod filling stage investigated in two contrasting genotypes (Capitol and Pollen) cultivated under ample (HN) or limiting nitrate (LN) supply. Seed yield was significantly reduced in N limitation and its reduction rate was much lower in Capitol than in Pollen compared to HN treated plants. Amino acid and protein content was higher in Capitol than in Pollen at bolting stage. They gradually decreased during plant development but not significant between two cultivars and/or two treatments. Glucose, fructose and sucrose content were 1.8-,1.6- or 1.25-fold higher in LN condition than in HN condition, respectively. Amino acid and sucrose content in phloem were largely higher in Capitol than in Pollen under LN condition. These results indicate that the higher seed yield might be related to greater transport ability of amino acid and sucrose in phloem under LN condition.

• Composites Research
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• 제36권5호
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• pp.369-376
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• 2023

본 연구에서는 복합소재의 기지재로 활용되고 있는 에폭시 고분자의 가교율이 항복표면에 미치는 영향을 분자동역학 해석을 통해 평가하고자 한다. 분자동역학 해석을 활용하여 가교율에 따른 에폭시 모델을 형성한 후, 상온-대기압 조건하에서 단축 변형 해석 및 평면응력 조건을 고려한 다축 변형 해석을 수행하였으며, 해석 데이터를 통하여 가교율에 따른 영률, 항복점, 항복표면, 그리고 경화지수를 도출하였다. 해석 결과, 영률 및 응력은 기존 선행 연구들에서 조사되었듯이, 가교율에 따라 증가하는 경향을 확인하였다. 다축 변형 시에는, 이러한 가교율과 도출된 응력간의 관계가 하중의 방향에 따라 의존적임을 확인하였는데, 가교율이 증가할수록 단축 인장 영역에 비해, 이축 압축 영역의 항복표면은 빠른 속도 팽창하였으며, 이로 인한 항복표면의 상이함을 관측하였다. 이를 통해, 고분자 소재의 항복 표면의 압력의존성은 소재의 가교 정도에 의존적이며, 항복이 진행될수록, 압력의 존성은 동일 소재 하에서도 변할 수 있음을 확인하였다.

• 한국작물학회:학술대회논문집
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• 한국작물학회 2000년도 춘계 학술대회지
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• pp.72-73
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• 2000

• 한국작물학회:학술대회논문집
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• 한국작물학회 2000년도 춘계 학술대회지
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• pp.282-283
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• 2000

• 한국작물학회:학술대회논문집
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• 한국작물학회 1989년도 춘계 학술대회지
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• pp.98-99
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• 1989

• 한국작물학회:학술대회논문집
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• 한국작물학회 1989년도 춘계 학술대회지
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• pp.52-53
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• 1989

• 한국작물학회:학술대회논문집
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• 한국작물학회 2005년도 춘계학술발표회 요지
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• pp.186-187
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• 2005

• 한국작물학회:학술대회논문집
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• 한국작물학회 2003년도 추계 학술발표회 요지
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• pp.66-67
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• 2003