• 한국작물학회지
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• 제65권4호
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• pp.327-338
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• 2020

최근 한국의 기온은 지구 온난화로 인해 급격히 상승하고 있으며 지난 40년 동안 한국의 기온은 1980년대 초에 비해 약 1.26℃ 상승했습니다. 지역 별로는 강원도 서부 지역이 1.76℃로 가장 높았고 전남도가 0.96℃로 가장 낮았다. 기온이 계속 상승함에 따라 현재의 표준 재배 방법으로 쌀 수확량이 감소할 것으로 전망되고 있다. 지구 온난화로 지역에서 매년 벼농사를 할 수 있는 기간이 과거에 비해 증가하여 태백시 110일에서 부산과 광양의 180일까지 지역별 다양한 모습을 보이고 있다. 또한 모든 지역에서 2000년 이전에 비해 이앙 시기가 3-5일 지연되는 것으로 분석되었다. 쌀의 연평균 생산량은 1980년대 이후 밥쌀용 품종의 평균 생산량을 분석했을 때 증가 추세를 보였으며 특히 1990년대 초반에 개발된 품종들의 생산성이 급격히 증가한 것으로 나타났다. 생육기간 평균 기온과 벼 수확량의 관계는 1996년 전후로 크게 구분되었다. 평균 기온이 높을수록 개발 품종의 수확량은 1996년까지는 낮아졌으나 1996년 이후 평균 기온은 개발된 품종의 생산성 추세를 나타내지 않았습니다. 1999년부터 2016년까지 전국의 작물 재배 결과와 개발 품종 및 최근 개발 품종의 연간 수확량 변화를 분석하여 개발 된 벼 품종의 기후 변화 적응성을 평가하기 위하여 국내 작물의 생육 현황을 조사한 결과 2000년대 초반에 개발된 조생종 태봉벼(2000)와 운광벼(2004)와 1980년대에 개발한 오대벼의 연간 생산량을 비교 한 결과 기온 상승에도 불구하고 2000년대에 개발된 품종이 상대적으로 수량성이 높게 나타났다. 최근 중만생종으로 개발된 삼광벼 (2003)와 새누리벼(2007)의 연간 생산성은 1970년대에 개발된 추청벼와 같은 초기 개발 품종보다 높았다. 빠르고 지속적인 기온 상승에도 불구하고 벼 재배 기술과 품종 개발은 기후 변화에 잘 적응하여 지속적으로 개발되고 있는 것으로 평가되었다. 그러나 벼의 생물학적 잠재력은 한계에 도달할 수 있고 특히 이상기상의 빈도와 강도가 온난화와 동반하여 발생하고 있어 지속적인 대응 기술 개발이 필요하다.

• 한국환경생태학회:학술대회논문집
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• 한국환경생태학회 2003년도 추계학술논문발표회 논문집
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• pp.143-146
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• 2003

• 한국수소및신에너지학회논문집
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• 제25권6호
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• pp.629-635
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• 2014

This paper presents annual energy production (AEP) by a 1.5kW wind turbine due to be installed in Deokjeok-Do island. Local wind data is determined by geometric shape of Deokjeok-Do island and annual wind data from Korea Institute of Energy Research at three places considered to be installed the wind turbine. Numerical simulation using WindSim is performed to obtain flow pattern for the whole island. The length of each computation grid is 40 m, and k-e turbulence model is imposed. AEP is determined by the power curve of the wind turbine and the local wind data obtained from numerical simulation. To capture the more detailed flow pattern at the specific local region, Urumsil-maul inside the island, fine mesh having the grid length of 10m is evaluated. It is noted that the input data for numerical simulation to the local region is used the wind data obtained by the numerical results for the whole island. From the numerical analysis, it is found that a local AEP at the Urumsil-maul has almost same value of 1.72 MWh regardless the grid resolutions used in the present calculation. It is noted that relatively fine mesh used for local region is effective to understand the flow pattern clearly.

• 대한토목학회논문집
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• 제32권6A호
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• pp.369-378
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• 2012

이 연구에서는 풍력 터빈 블레이드의 형상 최적화를 위한 직접탐색 기반의 최적화 기법을 적용하고, 최적화 기법간의 성능을 비교하여 효과적인 방법을 제안하고자 하였다. 이를 위하여 수평축 풍력 터빈의 최적설계 코드인 HARP_Opt(Horizontal Axis Rotor Performance Optimizer)을 기반으로 연간 발전량 평가 방법을 수정하고, HARP_Opt에서 적용하고 있는 기존의 유전자 알고리즘과 함께 패턴 서치 방법을 추가 적용하였다. 이를 1MW급 풍력 발전 터빈 블레이드의 단면 형상 최적 설계 문제에 적용하였으며, 기존의 유전자 알고리즘 및 마이크로 유전자 알고리즘, 그리고 패턴 서치 방법의 성능을 비교한 결과, 연간 발전량과 해의 일관성 면에 있어서는 패턴 서치 방법이 상대적으로 우수하였으며, 계산시간 측면에서는 마이크로 유전자 알고리즘이 상대적으로 우수한 것으로 분석되었다.

• Journal of Plant Biology
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• 제29권2호
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• pp.95-107
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• 1986

Seasonal changes in pool size, inflow rates in biomass and phosphorus, and the efficiency of phosphorus use in the stand of three populations (Helianthus tuberosus, Artemisia princeps and Phalaris arundinacea) in the basin of the Mt. Geumoh were investigated. During the early growing period, in the three species populations the relative size of the phosphorus pool of population was larger then that of its biomass pool, but that of the phosphorus pool of belowground part decreased more rapidly than that of its biomass pool. In the A. princeps and P. arundinacea populations, the phosphorus inflow rate was markedly high during the soil thaw in early spring and its seasonal change pattern was different from that of the biomass production rate, showing two peaks in March and June. But in the H. tuberosus population, the two seasonal change patterns were alike. The annual biomass production was 2283 gDM m-2 in the H. tuberosus, 1884 m-2 in the A. princeps and 1879 gDM m-2 in the P. arundinacea population, and the annual phosphorus inflow was 11.35, 9.63 and 7.60 gP m-2, respectively. The P. arundinacea population showed the smallest LAI peak(5.4 in early June), and the largest NAR peak (36.9 gDM m-2wk-1) RGR peak (0.15g g-1 wk-1) among the three species populations. The seasonal change patterns in whole plant EPU of the three species populations showed the bell shape, but the annual EPU values among them were markedly different. It was noticed that the population with the highest RGR showed the highest EPU among the three species populations while the population with the lowest RGR showed the lowest EPU among them.

• 한국수소및신에너지학회논문집
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• 제33권6호
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• pp.643-659
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• 2022

For the economic analysis of fuel cells, levelized cost of electricity was calculated according to the type, capacity, and annual production of the fuel cells. The cost of every component was calculated through the system component breakdown. The direct cost of the system included stack cost, component cost, assembly, test, and conditioning cost, and profit markup cost were added. The effect of capacity and annual production was analyzed by fuel cell type. Sensitivity analysis was performed according to stack life, capital cost, project period, and fuel cost. As a result, it was derived how much the economic efficiency of the fuel cell improves as the capacity increases and the annual production increases.

• 수산해양기술연구
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• 제47권3호
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• pp.203-213
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• 2011

The age and growth of flathead grey mullet, Mugil cephalus, were studied using samples collected from the coastal water of Yeosu from September 2009 to August 2010. Spawning season estimated from the gonadosometic index (GSI) was from November to January. A method for increasing the readability of the otolith was described and criteria for the interpretation of otolith was provided. The annual ring was formed in September once a year. Annual ring in otolith for flathead grey mullet is validated for fish aged 1-8 using the marginal increment analysis. Using the sectioned otolith, between reader precision was 84%. Also, Within-reader agreement for sectioned otolith age readings was higher (reader 1=84%, reader 2=87%). The relationship between fork length and total weight was TW=$0.022FL^{2.818}$. The estimated von Bertalanffy growth parameters for the flathead grey mullet were $L_{\infty}$=67.97cm K=0.164/year and $t_o$=-0.81year.

• The Korean Journal of Ecology
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• 제10권3호
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• pp.109-118
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• 1987

The production and decomposition rates of litters were studied in three mountains, Mt. Halla, Mt. So-back and Mt. Tae-back. The amounts of N, P, K, Ca and Na in the soils were measured and the relationships between the mineral nutrients and decay rates were reserched, The annual litter production was the most as $1, 077.3g/m^2$ and the least as $248.0g/m^2$ in a stand of Quercus acutissima at 820m of the Mt. So-back and at 1, 350m of the Mt. So-back among the study sites, respectively. The decay rates of litter was the highest as k=0.448 and the lowest as k=0.082 in a stand of Q. acutissima at 820m of the Mt. So-back and at 1, 450m of the Mt. Tae-back at 1, 450m of the Mt. Tae-back among the study sites. The higher altitude was, the slower the decay rates were. The annual contents of mineral nutrient and their amounts inputted into the forest soil were proportional to the decay rate of organic metters.

• 한국유기농업학회지
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• 제18권4호
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• pp.489-509
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• 2010

The object of this study is to analyze marketing situations and to suggest developing issues for organic farming. Organic agricultural products (OAP) has been steadily grown by an annual 36.4 percent over the past ten years, and production of OAP took up 4.5 percent of the Environmentally friendly agricultural products (EFAP) in 2009. 9,403 farmers, cultivated area 13,343ha and production 108,810 M/T in Organic agriculture are respectively formed 0.8 percent, 0.8 percent and 0.6 percent of Korea agriculture in 2009. And production of livestock products to have been certificated from the year 2005 was over 10,000M/T in 2008. OAP is mainly distributed by direct marketing system. The market size of OAP is 188.5 billion in 2008 and has been grown by an annual 30.1 percent. The price difference between OAP and general agricultural products is about 65.8 percent. Several issues on the marketing system of OAP are as follows : overcost of OAP marketing socially, imbalance of supply and demand, absence of standard price, institutional insufficiency to marketing within wholesale market, retail price inflexibility of consumer's cooperative, and so on.

• 한국초지조사료학회지
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• 제11권1호
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• pp.17-21
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• 1991

A field experiment was carried out to determine the effects of nitrogen(N) fertilization levels(0, 30, 60, 90 and 120 kg/ha) in early spring on the growth, dry matter(DM) yield, seasonal distribution of production and nutritive value of grasses. Additional N after the first, second and third harvest were applied as 60, 60 and 30 kg/ha, equally in 1989. Grass growth and DM yield were significantly increased(p$NO_3$-N concentration was not affected by N level of early spring. It is suggested that, therefore, N application in early spring is essential, and 60 to 90 kg/ha of N application may be desirable in early spring.