• 한국농공학회논문집
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• 제61권5호
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• pp.23-31
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• 2019

Crop response to weather and internal water pressure changes is more sensitive to crop water stress than soil water content. Recently, its implementation to optimal irrigation scheduling has been receiving much attention. This study was conducted to determine and compare the theoretical crop water stress index (CWSI) using meterological data and canopy temperature collected from three different irrigation treatments, which were Tr-1 plot (rainfed), Tr-2 plot (50% of daily evapotranspiration (ET) irrigated) and Tr-3 plot (75% of daily evapotranspiration (ET) irrigated). The readings of canopy temperature and CWSI were significantly different among irrigation treatment schemes. The average canopy temperatures and CWSIs of Tr-1 and Tr-3 plots were $34.6^{\circ}C$ and $32.6^{\circ}C$, 0.79 and 0.64, respectively. Solar radiation had the biggest correlation with CWSI (R=0.68) which was followed by wind speed, relative humidity and air temperature. Overall, the findings of this study indicated that canopy temperatures and CWSIs could be further used for irrigation scheduling for crop growth.

• 한국태양에너지학회 논문집
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• 제26권4호
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• pp.93-100
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• 2006

An experimental study of a counterflow heat exchanger was performed. The heat exchanger had an effective heat transfer length of 1000mm and was operated in a counterflow arrangement with hot water($30{\pm}0.5^{\circ}C$, $Re_i=3500{\sim}20000$) in the inner tube(copper tube, $d_0=9.52mm$) and cold water($15{\pm}0.5^{\circ}C$, $Re_{DH}=10700{\sim}39000$) in the annulus(copper tube, $D_0=19.05mm$). Overall heat transfer coefficients were calculated and heat transfer coefficients in the inner tube and the annulus were determined using Wilson plots. The inner Nusselt number was compared with that of Gnielinski's correlation and they agreed within ${\pm}10%$ error. The trends were typical for a fluid-to-fluid heat exchanger with the overall heat transfer coefficient increasing with both inner and annulus flow rates. In the range of this experiment, Nusselt numbers for the inner tube flow were almost identical with those of the annulus flow at the same Reynolds number.

• 한국환경농학회지
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• 제15권4호
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• pp.442-447
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• 1996

화본과 잡초를 방제하기 위하여 사용되고 있는 quizalofop-ethyl의 토양흡착 양상을 구명하기 위하여 실험을 수행한 결과는 다음과 같다. 제초제 quizalofop-ethyl이 토양흡착 평형에 도달하는 시간은 24시간이었으며 흡착등은 곡선에서 plateau를 형성하지 않았을 뿐만 아니라 토양 유기물 함량이 많을수록 온도가 높을 수록 흡착량은 증가하였다. Freundlich plot의 상관계수(r)값은 연곡통 0.998, 남원통 0.995이며 흡착상수(K)는 연곡통 4.710, 남원통 10.414였다.

• 한국작물학회지
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• 제41권6호
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• pp.634-639
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• 1996

근래에 육성된 한국산 녹두품종에 대하여 용도상 분류 기준이 되는 하배축신장성과 주요 성분함량을 조사하여 품종 육성의 기초 자료로 활용하고자 수행하였던 바 그 결과를 요약하면 다음과 같다. 1. 하배축 신장성이 큰 품종은 4234-697과 금성녹두였으며 남평녹두는 중간정도, 선화녹두는 작았다. 2. 파종 후 치상온도가 높을수록 하배축 신장은 양호하였는데 고온에서는 파종직 후부터 급속한 신장을 나타냈다. 3. 냉장고에 저장한 종자의 하배축신장성은 상온에 저장한 종자보다 하배축신장성이 양호하였다. 4. 종자크기와 하배축신장성과는 품증에 따라 각각 다른 상관정도를 보였으나 유의성은 인정되지 않았다.

• 한국압력기기공학회 논문집
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• 제16권1호
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• pp.49-55
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• 2020

Creep rupture data for Alloy 690 steam generator tubes in a pressurized water reactor are essentially needed to demonstrate a severe accident scenario on thermally-induced tube failures caused by hot gases in a damaged reactor core. The rupture data were obtained using the tube specimens under different applied-stress levels at 650℃, 700℃, 750℃, 800℃, and 850℃. Important creep constants were proposed using various creep laws in terms of Norton power law, Monkman-Grant (M-G) relation, damage tolerance factor (λ), and Zener-Hollomon parameter (Z). In addition, a creep activation energy (Q) value for Alloy 690 tube was reasonably determined using experimental data. Creep behaviors such as creep strength, creep rates, rupture elongation showed the results of temperature dependence well. Modified M-G plot improved a correlation of the creep rate and rupture life. Damage tolerance factor for Alloy 690 tubes was found to be λ =2.20 in an average value. Creep activation energy for Alloy 690 tube was optimized for Q=350 (kJ/mol). A plot of Z parameter obeyed a good linearity, and the same creep mechanism was inferred to be operative in the present test conditions.

• KSBB Journal
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• 제13권1호
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• pp.44-51
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• 1998

Hydrolysis and adsorption reversibility experiments were run for initial enzyme activity of 4.48, 9.65, 11.19 and 17.14U/mL at a temperature 30$^\circ C$. The chitin particle size corresponded to a mean particle diameter of 0.127mm, and the initial concentration of chitin was 10mg/mL. After approximately 2hrs, the enzyme activity remained constant in a speudo-steady state. The amounts in the bulk [E] and the amounts of enzyme adsorbed on the chitin surface [E] are plotted on Lineweaver-Burk plot to yield a linear relationship with a correlation coefficient of 0.99, a slope of 2.79cm$^-1$ and an intercept of 0.08$\textrm{cm}^2$/U. From this parameters, the values of [E$_T$] and $K_E$ were calculated to be 12.5U/cm$^2$ and 34.88U/mL. respectively, Adsorption isotherm of the enzyme on the particles showed a well developed plateau of 1.35$\times$10$^-3$, 4.72$\times$10$^-3$, 4.42$\times$10$^-3$, 8.58$\times$10$^-3$U/cm$^2$ at 30$^\circ C$. To determine the specificity of chitinase for crystalline chitin, the free energy of adsorption was measured, and its was determined as about -14.62~-18.8kJ/mol.

• 물과 미래
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• 제14권3호
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• pp.37-46
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• 1981

본 연구에서는 수문관측자료가 없는 지점에서도 확률홍수량을 구할 수 있는 확률홍수량의 산정공식을 유도하였다. 연구 대상유역으로는 한국의 주요하천인 한강, 금강, 영산강, 섬진강, 낙동강을 택하였고, 분석지점으로는 5대강 유역의 24개 수문관측소를 선정하여 여기서 얻은 홍수량자료를 Weibull-Plot와 Gumber-Chow 방법에 의한 분석을 통하여 T년 확률홍수량을 구하고 유역면적, 유로장, 유역형상계수, 유역평균경사, 하천경사를 확률홍수량에 영향을 미치는 지형인자로 하여, 이들 확률홍수량과 지형인자와의 상관관계를 분석하여 확률홍수량 공식을 유도하였다. Gumbel-Chow 방법에 의한 확률홍수량과 지형인자의 상관관계 분석결과, 유역면적 A의 상관이 너무 높게 나타나 위 방법에 따라 구한 확률홍수량과 지형인자와의 상관관계 분석결과에 의하여 재기년에 따른 확률 홍수량과 지형인자와의 상관관계 분석결과에 의하여 재기년에 따른 확률 홍수량 공식을 유도하였다.

• Journal of Plant Biology
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• 제37권1호
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• pp.1-8
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• 1994

The effects of fetilization on the structure and function of an early successional Miscanthus sinensis grassland were investigated in an old-field ecosystem at Honjo city, Saitama Prefecture, Japan from 1981 to 1982. Compared to control plot, life form composition of treatment plot was characterized by a decrease of phanerophytes and an increase of hemicryptophytes. Fertilization had a beneficial effect on the growth in aboveground phytomass of M. sinensis, the dominant species. However, it did not cause a change in the total number of stems of M. sinensis. Annual increment of patch diameter of M. sinensis was estimated to be 6-8 cm on an average and there was no significant differecne in the growth rate of patch size between fertilized and nonfertilized plots. To estimate the aboveground phytomass of M. sinensis, several non-destructive parameters were examined. As a result, the patch size showed a high correlation with aboveground phytomass. Thus the patch size was suggested to be most applicable to its estimation. Diversity indices based on phytomass data of component species were increased slightly by fertilizatin, because relative dominance of some other species, especially of Artemisia princeps increased, while that of M. sinensis decreased. Fertilizer application resulted in a decrease in the total number of species.

• 스마트미디어저널
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• 제8권1호
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• pp.82-91
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• 2019

This study provides the analysis and prediction of fruits diseases related to weather conditions (temperature, wind speed, solar power, rainfall and humidity) using Linear Model and Poisson Regression. The main goal of the research is to control the method of fruits diseases and also to prevent diseases using less agricultural pesticides. So, it is needed to predict the fruits diseases with weather data. Initially, fruit data is used to detect the fruit diseases. If diseases are found, we move to the next process and verify the condition of the fruits including their size. We identify the growth of fruit and evidence of diseases with Linear Model. Then, Poisson Regression used in this study to fit the model of fruits diseases with weather conditions as an input provides the predicted diseases as an output. Finally, the residuals plot, Q-Q plot and other plots help to validate the fitness of Linear Model and provide correlation between the actual and the predicted diseases as a result of the conducted experiment in this study.

• Journal of Forest and Environmental Science
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• 제26권1호
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• pp.1-7
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• 2010

Species diversity is one of the most important specifications of biological societies. Diversity of organisms, measurement of variety and examination of those hypotheses that are about reasons of diversity are such as affairs that have been desired by the ecologists for a long time. In this research, diversity of plant species in forest region, numbers of 60 sample plots in 256.00 square meters have been considered in random - systematic inventory was considered. In each sample plot, four micro-plots in 2.25 square meters in order to study on herbal cover, were executed that totally 240 micro-plots were considered. At each plot six diversity indices in relation to physiographic factors (slope, geographical aspect and altitude from the sea level) were studied. The results indicate that species diversity is more in the northern direction and also species diversity in slops less than 30% has the most amounts. Factor of altitude from the sea level did not have meaningful relation with species diversity. Through study on correlation of the numbers of species in sample plots with indices and also process and role of indices in different processors of analysis, Simpson's reciprocal index was suggested as suitable index in this type of studies.