• Asian-Australasian Journal of Animal Sciences
• /
• 제12권6호
• /
• pp.891-894
• /
• 1999

A field experiment was conducted with Calliandra calothyrsus of fifteen provenances to evaluate the variation in the condensed tannin content of fresh leaves. Plants were raised in a nursery for three months and planted in the field. Experimental design was line planting of double hedgerows (3 m long plot, 1/2 meter interval, 45 plants in each plot) with 5 replicates. Plants were lopped every 5 months and samples (10 different plants within a plot; 4 newly flushed leaves, 4 partially expanded leaves and 4 mature full expanded leaves from each of 10 trees in a plot) were collected and were put on ice before transfer to the laboratory. Proanthocyanidine was extracted in aqueous acetone, and total extractable proanthcyanidine (TEPA) and total proanthocyanidine (TOPA) were measured. In addition, proximate analyses were made of different provenances. Crude protein contents varied from 19.74% to 16.45%; in vitro organic matter digestibility ranged from 36.09% to 23.32%. TEPA content ranged from 11.22 to 16.01 (measured as absorbance at $550nm,\;g^{-1}$ DM) and TOPA from 24.57 to 31.72 (measured as absorbance at $550nm,\;g^{-1}$ DM) TEPA and TOPA had a positive correlation, whereas crude protein content of Calliandra was negatively correlated with TEPA and TOPA. Provenances, such as Georgesville (Belize), local, Coban (Guatemala), Patulul (Guatemala), Bombana (Mexico) can be selected on the basis of nutritive value of fodder.

• 한국초지조사료학회지
• /
• 제12권2호
• /
• pp.98-103
• /
• 1992

With a purpose of finding out the effects of cattle slurry application on thc nutrient contents of herbages and energy productivity in grassland, a field experiment was conducted with two times and five levels of cattle slurry application. The experimental field was designed in a split-plot with threc replications, and lasted from September, 1986 to October, 1990 at the Livestock Experiment Station in Suweon, The results obtained are summarized as follows: 1. The net energy(NEL, StE and TDN) contents of grasses in the plots with cattle slurry application just after cutting were slightly higher when compared to manuring 15 days after cutting. but DCP content has reverse trend. 2. Average net energy(NEL. StE and TDN) and DCP production of the plot with cattle slurry application 15 days after cutting were insignificantly increased by 26 % than those of manuring just after cutting. The energy and DCP yields in the plot with cattle slurry and with slurry + mineral fertilizer were decreased by 21 -27 % and 8- 11 %, respectively than those of the plot with single dressing of mineral fertilizer. 3. Mineral contents of grasses were not significant difference among the treatments of cattle slurry. but considering nutrient balance of animals, application of cattle slurry of 30-$60m^3$/ha with mineral fertilizer was profitable as compared to the other treatments.

• 한국농공학회지
• /
• 제12권2호
• /
• pp.1960-1964
• /
• 1970

본시험사업기간(本試驗事業期間)이 $9{\sim}2$월초(月初) 사이기 때문에 시험포장(試驗圃場)을 임대(賃貸)하여 흡수관리설공사(吸水管理設工事)가 끝나자 이어 장려품질(品質)인 맥류(麥類) 2종(種) (밀 : 농림 4호 쌀보리 : 도원)을 파종하고 발아상태(發芽狀態)와 초기생육(初期生育)만 조사(調査)하고 나머지는 내년(來年) $1{\sim}6$월(月) 사이에 조사(調査)를 완료(完了)하고 이어 벼의 시험(試驗)을 하기로 한다.

• 대한조선학회논문집
• /
• 제56권5호
• /
• pp.464-471
• /
• 2019

The acoustic power is a major acoustical characteristic of an underwater vehicle and could be measured in a reverberant water tank. In order to obtain accurate measurement results, the acoustic field formed by the sound source should be investigated quantitatively in the reverberant water tank. In this research, the acoustic field of a reverberant water tank containing an underwater sound source has been analyzed by using an acoustic radiosity method one of the numerical analysis methods suitable for the acoustic analysis of the highly diffused space. The source level of the underwater sound source and acoustical properties of the water tank input to the numerical analysis have been estimated by applying the reverberant tank plot method through a preliminary experiment result. The comparison of the numerical analysis result with that of the experiment has verified the accuracy of the acoustic radiosity method.

• 한국작물학회:학술대회논문집
• /
• 한국작물학회 2017년도 9th Asian Crop Science Association conference
• /
• pp.201-201
• /
• 2017

Delayed stem senescence of soybean is a phenomenon of retarded leaf and stem yellowing, where plants maintain a high stem water content and remain chlorophyll in leaf and stem at maturity stage. This phenomenon was one of the most important physiological disease in Japanese soybean cultivation. The occurrence of delayed stem senescence was affected by sowing time. And the most of Japanese field, soybean seeds were sowed in June. June is the rainy season in Japan, and the soil water content of field become higher in this season. In this study, the effects of late sowing (July sowing) on the yield and the occurrence of delayed stem senescence in soybean cultivars Enrei, Tachinagaha and Ayakogane were examined from 2013 to 2015, in the experimental farm at Nihon University (Fujisawa-city, Kanagawa, Japan). The seeds of all cultivars were sowed in June (June-normal density plot) or July (July-normal density plot, July-high density plot and July-super high density plot) in field experiment. The pot experiments were carried out in 2014. In all cultivars, the yield of July-high density plot and July-super high density were higher than that of June normal density plot. And the yield of June-normal density plot was the same as that of July-normal density plot. In all cultivars, the occurrence of delayed stem senescence was increased by seeding in June sowing. And in July sowing plots, no significance difference in the occurrence of delayed stem senescence was observed among density plots. One of reason about the increasing the occurrence of delayed stem senescence in June-normal plot was the increasing of the damaged seeds by bean bugs. Add one of reason about the decreasing of the occurrence of delayed stem senescence of July plots was the decreasing of the amount of cytokinin supplied from root to top and water stress after the flowering time was improved compared with the June plot. In conclusion, the yield of Enrei, Tachinagaha and Ayakogane were not changed by changing the sowing time from June to July. In all cultivars, the occurrence of delayed stem senescence were decreasing by seeding in July.

• 한국농공학회논문집
• /
• 제48권3호
• /
• pp.97-106
• /
• 2006

The pollutant concentrations at experimental paddy plots with three (excessive, standard, reduced) different fertilization rates were investigated during 2001-2002 irrigation seasons. Mean concentrations of pollutants in ponded water were not significantly different among three experimental plots, but the T-N concentrations in percolated water significantly depended on fertilization rates. The T-N, T-P and $COD_{Cr}$, concentrations in ponded water during early irrigation season (late May to mid-June) were much higher than those during later irrigation season likely due to fertilization and low uptake by young rice crops. The T-N concentrations decreased but the concentrations of T-P and $COD_{Cr}$, increased three days after tillering fertilization. The removal rates of T-N by paddy plots were $0.13-0.16g/m^2{\cdot}d$ for an excessive fertilization plot, $0.08-0.25g/m^2{\cdot}d$ for a standard fertilization plot, and $0.03-0.34g/m^2{\cdot}d$ for a reduced fertilization plot three days after tillering fertilization. On the other hand, T-P and $COD_{Cr}$, were released three days after tillering fertilization.

• The Korean Journal of Ecology
• /
• 제9권3호
• /
• pp.161-184
• /
• 1986

An experiment was made in order to analyze the growth characteristics and productivity of Zoysia japonica under control, mowing and TIBA treatment conditions at the experimental farm of Kyung Hee univ. from May 26 to Oct. 1 in 1985. The field was planned by the randomized block design method and each treatment was given to three plots (2${\times}$2, 4${\times}$4 and 10${\times}$10 cm) and was replicated three times. Each plot was 1$m^2$ for Zoysia japonica. The sampling of each plot was taken once a week after sowing. In order to know the dry matter of total standing crops, kept 9$0^{\circ}C$ and weighted each organ of the plants. Total leaf area of a plant was measured by drawing method. The author adopted the growth analysis of English School. The increasing rates of numbers of leaf and stem were remarkably high in each plot between 10th and 12th weak after sowing and it was highest in TIBA treated plot. The increasin rate of leaf area in each plot was remarkably high beween 10th and 12th week and the maximum value of leaf area was 274.00c$m^2$ in TIBA treated plot of 100 plants/$m^2$. The increasing rate of standing crop was remarkably high between 10th and 12th week and the high increasing tendency in TIBA plot resulted from TIBA. The positive correlationship was founded between standing crop and leaf area. The evaporation rather than temperature acted as a main factor of negative correlation with standing crop during the experiment period. Solar radiation had a high positive correlation in the lower density of plot. C/F ratio was low, during the growth period, from 10th to 12th week after sowing and was low in the higher density under each treated plot. T/R ratio was not constant during the sampling period but was high in the lower density. The increasing rates of RGR and NAR were high between 11th and 12th week after sowing. Leaf area ratio was high in higher density in each plot and not constant in all treated plot.

• 한국초지조사료학회지
• /
• 제17권4호
• /
• pp.371-378
• /
• 1997

The purpose of this research was to investigate the effect of P fertilization and cutting fkquency without N fertilizer on nutritive value and nitrogen fixation activity of alfalfa. A field experiment was conducted on the experimental farm of Kongju National University at Yesan from 1994 to 1996. The experimental design was a split plot design with two P levels as main plot and two cutting frequencies as the sub-plot. The results obtained are summarized as follows. Available phosphate, exchangeable Ca and Na in the soil were slightly increased with P fertilizer and basal treatment of lime. Average DM yield was 1.5 ton and 1.4 ton in second and third year. There was no significant difference within P level and cutting kquency. The first cut showed higest CP value as cutting times increased the value tend to be lowered. Crude protein content in 3 and 4 cutting regimes were from 16.3 to 16.6% 17.4 to 17.9% respectively, but no significant effect were found among the main and sub-plot. ADF and NDF in 1995 were ranged from 38.2 to 39.9, 45.1 to 58.1% respectively. ADF was 2% more higher in 1996 compared to previous year and NDF was slightly higher in 1996. There was significant difference of ADF between main plot in 1995. .P, Ca, K and Mg of 200kg P level with 3 times cutting treatment in 1995 and 1996 were 0.32 and 0.23, 0.95 and 0.84, 3.24 and 2.87, and 0.36 and 0.26. Significant difference of K and Mg between cutting frequency was observed in 1995. Nitrogen fixing activity of 400kg P fertilizer plots were higher than 200kg P level and 3 times cutting plot also showed higher acetylene reduction activity than that of 4 cutting per year. Phosphate level and cutting frequency treatment of did not significantly affect nitrogen fixation activity.

• 한국전기전자재료학회:학술대회논문집
• /
• 한국전기전자재료학회 2001년도 하계학술대회 논문집
• /
• pp.1069-1072
• /
• 2001

We described a method resonant mode identification in dielectric-rod loaded cylindrical cavity resonators. Resonant frequency of dielectric loaded cavity is calculated by analyzing the characteristic equation. The characteristic equation is solved by using the ContourPlot graph of Mathematica. As the result of comparing calculation value and experimental value of resonant frequencies, we know that the field representation of non-decaying mode is exact. The contour graph method is not a method using approximated representation of electromagnetic field variation at the outer area of dielectric in the resonators but a method using exact representation.

• 한국농공학회논문집
• /
• 제55권4호
• /
• pp.21-28
• /
• 2013

The objective of the study was to investigate the effect of rice straw mat, rice straw mat with PAM (Polyacrylamide) and gypsum addition on surface runoff and sediment discharge in field. Six experimental plots of $5{\times}22m$ in size and 3 % in slope prepared on gravelly sandy loam soil were treated with control, rice straw mat cover with gypsum and rice straw mat cover with gypsum and PAM. Radish in Spring and Chinese cabbage in autumn growing seasons were cultivated. Non point source (NPS) pollution discharge was monitored and compared among the treatments. Rainfall of the 10 monitored events ranged from 17.0 mm to 93.5 mm. Runoff coefficient of the events was 0.005~0.239 in control plot, 0~0.176 in rice straw plot with gypsum and 0~0.046 in rice straw mat plot with gypsum and PAM. When compared to the control plot, the runoff amount was reduced by 10.4~100 % (Ave. 60.8) in rice straw plot with gypsum and 80.7~100 % (Ave. 96.7 %) in rice straw mat plot with gypsum and PAM. The reduction of NPS pollution load was 54.6 % for BOD5, 71.5 % for SS, 41.6 % for TN and 61.4 % for T-P in rice straw with gypsum plot and 91.9 % for BOD5, 92.0 % for SS, 88.0 % for TN and 88.5 % for T-P in rice straw mat with gypsum and PAM plot. This research revealed that rice straw mat cover with soil amendments on the soil surface could not only increase the crop yield but also reduce the NPS pollution loads substantially.