• Horticultural Science & Technology
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• v.31 no.6
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• pp.706-713
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• 2013

With pot-grown 4-year-old 'Fuyu' persimmon trees, this study evaluated the effect of different nitrogen (N) rates during summer on fruit characteristics, changes of leaf nutrients after harvest, reserve accumulation, and early growth the following year. A total of 0, 36 g N in June, and 72 g N in June and July was fertigated to each tree using urea solution. All the fruits were harvested on Nov. 3. Although not significant, fruits were larger for the 36 g and 72 g N than the 0 g N. Fruits for the 0 g N, having lower N concentration, were softer and had a better coloration and higher soluble solids, indicating that they matured earlier. SPAD value on Nov. 3 was 19.2 for the 0 g N and 54.9 for the 72 g N, and then the values linearly decreased in all the treatments by Nov. 14, exhibiting rapid leaf senescence. Specific leaf weight, being the lowest for the 0 g N, also gradually decreased during this period. Increasing N level significantly increased cross-sectional area of the trunk. Leaf N concentration on Nov. 3 was 0.87% for the 0 g N, whereas it was 1.18 and 1.52% for the 36 g and 72 g N, respectively. The N fertigation tended to increase leaf concentrations of soluble sugars, starch, and amino acids. Contents of N, P, K, soluble sugars, starch, and amino acids per unit leaf area gradually decreased in all the treatments during the 11 days after harvest, and the extent of the decrease was the lowest for the 0 g N. On the other hand, those of Ca, Mg, and protein did not consistently change during this period. The N fertigation resulted in higher concentrations of N in dormant shoots on Nov. 14, and although not great, it also increased soluble sugars, starch, amino acids, and protein. Clear differences were found in number of flower buds per one-year-old branch and total shoot length per tree the following year. The 72 g N trees had 5.6-fold more flower buds and 1.9-fold more shoot length, compared with those of 0 g N trees. However, it was noted that tree growth the following year was not significantly different between the 36 g and 72 g N the previous year. It was concluded that N rate during summer should be adjusted with considering the changes of fruit maturation, mobilization of leaf nutrients, and reserve accumulation.

• Korean Journal of Environmental Agriculture
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• v.27 no.2
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• pp.171-177
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• 2008

The application in agricultural fields of pig slurry composting biofiltraton amending smell and nutrient unevenness, it is important for the appropriate nitrogen nutrient management to promote the availability of the crops and to minimize the risk of adversely environmental effects. The objective of this study was to determine the application rates of the preplant pig slurry composting biofiltration for red pepper(Capsicum annuum L.) by considering the yield response and the fruit quality such as sugar, capsaicinoid content. Red peppers were grown on plastic film ground under five different pig slurry(PS) application rates and mineral fertilizer(MF 100%) as a control. The effects of a single application of five different doses of PS: PS 0%(no kg N $ha^{-1}$), PS 50%(51.5 kg N $ha^{-1}$), PS 75%(77.3 kg N $ha^{-1}$), PS 100%(103 kg N $ha^{-1}$) and PS 125%(129 kg N $ha^{-1}$) were compared with the recommended mineral treatment(103 kg N $ha^{-1}$) in the pre-planting. The sidedressing N application(87 kg N $ha^{-1}$) was applied to the mineral fertilizer in all treatments. Red peppers were harvested at the mature red stage through five times from 72 days after transplanting(DAT) to 133 DAT. The results indicated that the yield of red pepper was increased with the increase of the N application rates from PS 0% to PS 100%. The highest yield was obtained in PS 100% by 20,843 kg $ha^{-1}$, although there were no significant differences in yield among PS 100, PS 125% and MF 100%. In addition, The contents of soluble sugar and capsaicinoids were not significantly different in all treatments. Accordingly, fertilization recommendations of red pepper to substitute PS for the mineral fertilizer were considered to PS 100%.

• The Korean Journal of Malacology
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• v.24 no.2
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• pp.109-119
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• 2008

In order to investigate the possibility of yearly-harvest, we carried out growth experiment(shell height, meat weight and condition index) for of the artificial oyster spat, which suspended in three different times before the season for natural spat around coastal waters of Gyeongnam Province. Shell growth of spats suspended in June showed higher than those in April and May. In meat weight, the growth of spats was significantly elevated from October, of which significant difference was observed depending on growing farms(Gosung$\geq$80 mm) and October on the meat weight level($\geq$5 g).

• Journal of The Korean Society of Grassland and Forage Science
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• v.40 no.4
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• pp.216-220
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• 2020

This field evaluated the effect of different yields on the drying rate of Italian ryegrass ("Kowinearly", Lolium multiflorum Lam.) hay during the spring season. The experiment was performed at Hwaseong, 2015. The different yields of the plot were selected by growth and development check. Three treatments were 35 t/ha(Y1), 45 t/ha(Y2), and 60 t/ha(Y3). After harvest with conditioner, it was conducted tedding 1/day. It was investigated patterns for changes in moisture content. The changes in moisture content were respectively Y1 from 78.9% to 14.4%, Y2 from 79.1% to 18.3%, and Y3 from 77.9% to 25.5% for 5days. It was no different significantly for changes in moisture content by yields from 1st day ~ 2nd day, But It was different significantly from 3rd day to 5th day. the content of neural detergent fiber(NDF) and acid detergent fiber(ADF) were respectively about 34%, 59%, regardless of yields (P>0.05). Crude protein of Yields Y1, Y2, and Y3 were respectively 6.9%, 8.7%, and 9.4% (P<0.05). The result of this study that the higher yields, the slower it dried. The Quantity is a factor to effect on drying rate.

• Magazine of the Korean Society of Agricultural Engineers
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• v.15 no.2
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• pp.2949-2967
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• 1973

The purpose of this study is to find out and determine the minimum consumptive use of water for Korean cabbage and turmp, so that the minimum water requirement can be secured always for a stable cultivation of these vegetables regardless of weather conditions. The experiment was conducted in two periods; first one from May to July and second one from August to October, each experiment with two varieties of cabbage and two varieties of radish with 2 replicants and 15 treatments. The results found from the above are briefly as follows: 1. Since the mean soil moisture equivalent 64 days after the treatment was 28.5% and the soil moisture content at the time was 2.67% which is far less than that of the wilting point, the crop seemed to be extremely caused by a drought. 2. The rate of 51 days after the seeding, soil moisture content of plot No.2 where irrigation has been continuous was the highest or 21.3%, whereas the plot No.14 without irrigations was 11.2% and the lowest. Therefore, the soil moisture content for the minimum qrowth seemed to be 20%. 3. The consumptive coefficient of Blaney and Criddle on cabbage in two periods were K=1.14 and 0.97 respectively, and on radish in two periods were K=1.06 and 0.86 respectively, thus, cabbage was higher than radish. The consumptive coefficient in the first experiment (May-July) was 0.17 to 0.20 higher than the 2nd experiment(August-October). 4. Nomally, cabbage and radish germinate within one week, however, the germination ot these crops which were treated with a suspended water supply from the beginning took two full weeks. 5. When it elapsed 30 days after seeding, the conditions in plot 1,2 and 3 were fairly good however, the crops in the plops other than these showed a withering and the leaves were withered and changed into high green due to an extrem drought. Though it was about same at the beginning, the drought damage on cabbage was worse than that on radish period, and the reasos for this appears in the latter that the roots are grown too deep. 6. The cabbage showed a high affinity between treated plots and varieties. Consequently, it can be said that cabbage is very suseptive to drought damage, and the yield showed a difference of 35% to 56% depending on the selection oe varieties. 7. The radish also showed a high affinity between the treated plots, however, almost us affinity existed between varieties. Therfore, the yield of radish largely depends on the extent of drought, and the selection of variety does not affect at all. 8. The normal consumptive use on cabbage is $0.62{\ell}/sec$, while that on radish is $0.64{\ell}/sec$, and the minimum optimum water requirement that was obtained in this study is $4,000cc/day/m^3$ or $0.462{\ell}/sec/ha$.

• Elastomers and Composites
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• v.34 no.3
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• pp.253-261
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• 1999

The cure properties of rubber compounds containing different adhesive compositions were examined. As the amounts of tannin were increased in the adhesive composition, the scorch time was increased and cure rate was decreased due to the size and shape of tannin molecules. Also, the effect of adhesive composition on the adhesion between rubber and fiber was examined by TCAT(Tire Cord Adhesion Test), The reinforcing cords used in this study were mon ofilaments of nylon 610 and nylon 66. According to the results, the optimum adhesion strength between rubber and fiber could be obtained with adhesives whose molar ratios of formaldehyde/resorcinol were above 5/1 in the recipes. Although the level of dip pick-up(DPU) on the reinforcing cord affects the adhesion strength, the DPU of nylon 610 monofilament did not affect the adhesion strength because the level of DPU was constant regardless of the adhesive compositions. In this case, the adhesion strength with the adhesive composition could be explained with the behavior of tannin in the adhesive.

• Korean Journal of Food Science and Technology
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• v.27 no.5
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• pp.697-702
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• 1995

Changes of physicochemical properties during the preparation of persimmon pickles and its optimal preparing conditions including salt concentration, soaking temperature, soaking time, amount of fermented soy paste, and ripeness of fresh pesimmon were investigated. The salinity and pH of soaking solution were rapidly dropped during 40 days of soaking, while their changes were negligible after 40 days of soaking. When the fermented soy paste was added to the soaking solution with $10{\sim}40%$ the pH dropped more slowly. Salt content in persimmon pickles was gradually increased during soaking and soluble tannin content was rapidly decreased during the first 10 days of soaking. L value of persimmon pickles was gradually decreased, but a/b value was slightly increased. The hardness of persimmon pickles was slightly increased up to the 20th day of soaking and then decreased. Most acceptable persimmon pickles were prepared when the less ripened fresh persimmons were soaked in 10% salt solution at $15^{\circ}C$ for 40 days, and the suitable amount of soy paste added to the soaking solution for preparing persimmon pickles was 20%.

• The Korean Journal of Pesticide Science
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• v.18 no.4
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• pp.314-320
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• 2014

The uptake and transportation patterns of the residual boscalid and chlorfenapyr were investigated from the soils to Korean cabbages. The recovery rates of the pesticides spiked in the soils and Korean cabbages were 87.5 to 105.2%. Korean cabbages were cultivated in soils treated with two different concentrations of the pesticides as low (3.0 mg/kg) and high (6.0 mg/kg) concentrations in greenhouse for 28 days. The initial level of boscalid was determined as 2.77 and 5.66 mg/kg for the low and high concentration of boscalid-treated soils, respectively. After 28 days of treatment, the residual boscalid in soils decreased to 0.53 and 1.60 mg/kg for the low and high concentration of boscalid-treated soils, respectively, and thus it was reduced to 71.7 to 81.9%. The initial level of chlorfenapyr was determined as 2.38 and 6.43 mg/kg for the low and high concentration of chlorfenapyr-treated soils, respectively. After 28 days of treatment, the residual chlorfenapyr in soils decreased to 1.36 and 2.91 mg/kg for the low and high concentration-treated soils, respectively, and thus it was reduced to 42.9 to 54.8%. The residual pesticide analysis was done with 2 day intervals from 21 days-cultivated Korean cabbages after seeding. Uptake rates of boscalid from the soil to Korean cabbages were 2.4 and 2.2% for the low- and high-concentration of boscalid-treated soil, respectively. However, the uptake rate of chlorfenapyr by the cabbages was 1.5 and 1.3% for the low and high concentration-treated soil, respectively. The uptake rate of chlorfenapyr by the cabbages was lower than that of boscalid. These results showed that the residual pesticides in soil could be absorbed by Korean cabbages depending on their physicochemical properties.

• Journal of Korean Society of Forest Science
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• v.109 no.3
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• pp.300-312
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• 2020

The growing stocks of young forests that are less than10 years of age have been excluded from the Korean forest resource statistics, despite the existence of standing trees; however, sustainable forest management and carbon removals in the forestry section require complete information regarding forest resources. This study developed a method to estimate the growing stocks for young forests from National Forest Inventory (NFI) data. After reviewing previous research on growth characteristics for young forests, we conducted stem analysis of major species, and examined stand characteristics by site index, based on real yield tables. Our statistical analysis results showed that there were few standing trees with diameters at breast height (DBH) above 6 cm in young stands, and that it would have taken 12 years, on average, to reach 6 cm DBH. This suggests that mean tree height by diameter should be assessed at the root, in order to assess growing stocks for young stands through the NFI. Moreover, the database system should be improved to differentiate tree species, since diverse shrubs, including trees, have been surveyed.

• Journal of Biosystems Engineering
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• v.8 no.1
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• pp.47-60
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• 1983

상온통풍(常溫通風)을 이용(利用)한 In-bin drying에 대(對)한 많은 실험결과(實驗結果)에 의(依)하면 우리나라 10월(月)의 기상조건(氣象條件)은 저온건조(低溫乾燥) system에 적합(適合)한 건조능력(乾燥能力)을 가지고 있는 것으로 나타났다. 최근(最近) Computer를 이용(利用)한 Simulation model이 개발(開發)되어 건조현상(乾操現象)에 관(關)한 경제적(經濟的)이고 효율적(效率的)인 분석(分析)이 가능(可能)하게 되었다. 이러한 분석결과(分析結果)에 의(依)하면 초기함수율(初期含水率)이 높은 벼를 Full-bin을 이용(利用)한 상온통풍건조(常溫通風乾操)를 할 경우(境遇) 건조기간(乾燥期間)이 길어지며 bin내(內)의 상층부(上層部) 곡물(穀物)이 변질(變質)되는 문제점(問題點)이 발생(發生)하였다. 또한 벼의 수확작업체계(收穫作業體系)가 관행(慣行) 및 Binder작업체계(作業體系)에서 점차(漸次) Combine작업체계(作業體系)로 전환(轉換)되어감에 따라 포장(圃場)에서의 건조(乾燥)가 어려우며 예취(刈取), 탈곡작업과정(脫穀作業過程)에서의 기계적(機械的)인 곡물(穀物) 손실(損失)을 줄이기 위(爲)하여 함수율(含水率)이 비교적(比較的) 높은 벼를 수확(收穫)하여야 한다. 본(本) 연구(硏究)의 목적(目的)은 상온통풍건조(常溫通風乾燥)에 있어서 건조능력(乾燥能力)을 증가(增加)시키기 위(爲)하여 곡물(穀物)을 일정기간(一定期間) 나누어서 bin에 넣고 건조(乾燥)를 하는 Layer drying의 Simulation model을 개발(開發)하고 이 Model에 수원지방(水原地方)의 7년간(年間) 평균(平均) 기상자료(氣象資料)를 입력(入力)시켜 곡물(穀物)의 초기함수율(初期含水率), 투입량(投入量), 투입기간(投入期間)의 변화(變化)에 따른 Layer drying현상(現象)을 규명(糾明)하는데 있다. Simulation에 사용(使用)된 bin의 크기는 직경(直徑) 2m, 깊이 1.5m이며 송풍(送風)팬의 용량(容量)은 0.5HP이었다. Simulation분석(分析) 결과(結果)를 요약(要約)하면 다음과 같다. (1) Layer drying의 Simulation model을 개발(開發)하였으며 이 Model은 벼의 상온통풍건조(常溫通風乾燥) 실험(實驗)에서 함수량(含水量) 변화(變化)의 이론치(理論値)와 실제실험치(實際實驗値)가 잘 일치(一致)하였다. (2) 곡물투입기간(穀物投入期間) 1일(日)을 Full-bin drying으로 간주(看做)할 때 Layer drying의 건조성능(乾燥性能)은 Full-bin보다 높은 것으로 나타났다. (3) 연속송풍(連續送風)(24시간(時間))을 할 경우(境遇) 곡물투입기간(穀物投入期間)이 증가(增加)함에 따라 건조기간(乾燥期間)의 감소경향(減少傾向)은 단속송풍(斷續送風)인 경우(境遇)보다 적었지만 건조기간(乾燥期間)은 단축(短縮)되었다. 그러나 건조(乾燥)에너지의 소모(消耗)는 단속송풍(斷續送風)일 때보다 크게 나타났다. (4) 단속송풍(斷續送風)(9 : 00AM~6 : 00PM)일 경우(境遇) 곡물투입기간(穀物投入期間)을 증가(增加)시키면 건조기간(乾燥期間)이 크게 줄어 들었다. (5) 곡물(穀物)의 초기함수율(初期含水率)이 21% 이하(以下)일 경우(境遇) 연속(連續) 및 단속송풍(斷續送風)에서 건조기간(乾燥期間)의 차이(差異)가 별로 없었다. (6) 곡물(穀物)의 초기함수율(初期含水率)이 높으면 Full-bin drying에서는 상부층(上部層)에 곡물(穀物)이 변질(變質)될 우려(憂慮)가 있으나 Layer drying에서는 곡물투입량(穀物投入量)을 조절(調節)하면 이것을 방지(防止)할 수 있었다. (7) 건조(乾燥)가 완료(完了)된 후(後) 층별(層別) 최종곡물(最終穀物) 함수율(含水率)은 모든 건조조건(乾燥條件)에서 동일(同一)하였으나 bin의 하부층(下部層)은 과건조(過乾燥) 물상(物象)을 일으켰다.