• Journal of The Korean Society of Grassland and Forage Science
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• v.39 no.1
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• pp.45-52
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• 2019

This experiment was carried out to study the change of productivity and feed value in different types of hilly pasture. The pasture utilized in the experiment was placed on the experimental farm of Pyeongchang Campus of Seoul National University. Forage production type(FP; Orchardgrass 18 + Tall Fescue 12 + Timothy 5 + White clover 5 kg/ha) and Public farm type(PF: Orchardgrass 12 + Tall Fescue 18 + Timothy 5 + White clover 5 kg/ha) pasture were established in September 3, 2014 and utilized (cutting or grazing) four times every year. Growth characteristics, yield and forage quality were investigated for two years. Plant height of grasses was the highest in the $1^{st}$ cutting and legumes was in the $2^{nd}$ cutting. Dry matter (DM) content was highest at every the $1^{st}$ cut grasses significantly lower at the $2^{nd}$ harvest (p<0.05). However, there was no significant difference in the $2^{nd}$, $3^{rd}$ and $4^{th}$ harvest in 2016. In the botanical composition change, the portion of legume was gradually increased after pasture establishment and the ratio of weed and bare land was higher at $2^{nd}$ and $3^{rd}$ cutting, but it was decreased at $4^{th}$ harvest. There was no significant difference in 2016 of fresh yield between two farm types (p>0.05). The yield of dry matter showed similar trend of fresh yield and forage production type was higher than that of public farm type (p<0.05). The forage intake by livestock was 1,452 kg/ha in 2015 and 1,743 kg/ha in 2016. Pasture utilization ratio of public farm type pasture was highest in the $3^{rd}$ grazing time. Forage quality of pasture in relation to management type had not significant difference, but there was difference in harvest times. Crude protein (CP) was the lowest in the $1^{st}$ harvest and total digestible nutrient (TDN) was highest in the $1^{st}$ harvest and lowest in the $4^{th}$ harvest. Based on the above results, it is found that the establishment of pasture suitable for farm's situation is important for set up of Korean model of hilly pasture. Although the forage production type is superior on forage productivity, it is recommended that the results will be provided as basic data for management of public farm type in the future.

• Journal of the Korean Wood Science and Technology
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• v.36 no.1
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• pp.69-78
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• 2008

Shearing strength test in tension type was investigated to determine the shear resistance of bolt and drift-pin connection of domestic larix glulam. The specimen was connected with bolt and drift-pin in the inserted plate type, and only bolt in the side plate type. The diameter of bolt and drift-pin used in the experiment are 12, 16 and 20 mm. The hole of bolt was drilled at the end-distance 5 d and 7 d. Tension load was loaded in the direction parallel to grain. The shear resistance was evaluated according to end-distance through this, the yield load was compared with the experimental yield load, using Larsen's formula. The prototype design strength is based on the yield load of end-distance 7 d and the reduction factor of end-distance 5 d was calculated. The results were as follows. 1. The average of maximum load of drift-pin connection was higher by 3~30% at the inserted type than at bolt connection with increasing diameter. In bolt connection, the average of maximum load of the side type was 1.54~2.07 times higher than that of the inserted type. In the same diameter, the average of maximum load of end-distance 7 d was higher by 8~44% than that of 5 d. 2. The bearing stress was 1.16~1.41 times higher at the inserted connection than at drift-pin connection, and 1.37~1.86 times higher at 7 d than at 5 d. Also, when the slenderness ratio was below 7.5 at drift-pin connection and below 6.0 at inserted connection, the lateral capacity was good. 3. The ratio of the experimental yield load and the predicted yield load calculated by Larsen's formula proposed by Larsen was 0.80~1.10 at inserted connection, and 0.75~1.46 at side connection. 4. When the inserted bolt connection was based on the yield load of end-distance 7 d, the reduction factor was 0.89 at 12 mm connection, 0.93 at 16 mm and 0.85 at 20 mm. The reduction factor was 0.89 at 12 mm the inserted drift-pin connection, 0.93 at 16 mm, 0.93 at 20 mm. The reduction factor was 0.79 at the side connection of the 12 mm bolt connection and 0.80 at 16 mm.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.63 no.1
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• pp.64-71
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• 2018

To improve the soil of reclaimed land, we added organic materials at a level of 3,000 kg/10 a. As a result, the electrical conductivity (EC) value of reclaimed soil decreased by 58%, the organic material content increased from 6.7 to 16.0 g/kg, the porosity increased from 1.57 to 1.31%, the soil hardness decreased from 20.2 to 17.9 mm and the plow layer was deepened from 19.8 to 26.8 cm. After these physiochemical improvements to the reclaimed soil, the growth phase of crops was improved compared to that of non-treatment crops. The height of kenaf (Hibiscus cannabinus L.) cultivated in the reclaimed land containing organic materials was increased by 18.8%. Especially, the improvement effects of pellet type manure compost and rice straw on kenaf were more preferable than those of other organic materials. When the kenaf was cultivated in the reclaimed land containing organic materials, the yield increased. The average yield of the treatment crops was 9,218 kg/10 a, 2.1 times higher than that of non-treatment crops. The most effective treatments to increase the yields were pellet type manure compost (10,848 kg/10 a, 148% increase), rice straw (120% increase) and chopped kenaf (95% increase). To increase the physicochemical enhancements to the reclaimed land soil and most improve yields, the most effective type of organic materials was the pellet. The organic material types that maintained a better growth phase and most increased the yield were the liquid and pellet types. When we used pellet type organic material, the plant height of kenaf was increased by 41% in comparison with that of the non-treatment crops and yield was increased by more than 122%. Additionally liquid type organic material improved the yield (by 127%).

• Korean Journal of Plant Resources
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• v.34 no.6
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• pp.542-554
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• 2021

In this study, we cultivated 115 Soritae and 86 Yakkong black soybean landraces collected from ten different locations in Korea. Then, the variations of three yield components (one-hundred seeds weight (HSW), number of seeds per pod (SPP), and yield per plant (YPP)) and three anthocyanins (cyanidin-3-O-glucoside (C-3-O-G), delphinidin-3-O-glucoside (D-3-O-G) and petunidin-3-O-glucoside (Pt-3-O-G)) were investigated according to landrace type and collection area. Both yield components and anthocyanin contents significantly varied between the soybeans demonstrating genetic differences. Soritae landraces had the highest average HSW and TAC, whereas Yakkong landraces displayed the highest average SPP irrespective of collection area. Relatively, Yakkong landraces from Gyeongsangnam-do (1697.29 mg/100 g) and Soritae landraces from Gyeonggi-do (2340.94 mg/100 g) had the highest average TAC. Principal component analysis clearly separated Soritae and Yakkong landraces. Moreover, TAC and C-3-O-G showed positive and significant associations in both Soritae (r = 0.972) and Yakkong (r = 0.885) landraces, while yield components showed negative or weak correlations with each other. Overall, ten landraces were identified as important resources owing to their high yield (>150 g/plant) and high level of TAC (>2300 mg/100g). This study could lay foundations to molecular level investigations and reinforce the use of Yakkong and Soritae landraces during cultivar development.

• Journal of the Korean Society of Tobacco Science
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• v.9 no.1
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• pp.45-55
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• 1987

For some basic information in tobacco breeding, the modes of inheritance and heritabilities for the twelve agronomic and chemical characters were estimated in the study of eight varieties partial diallel set. Additive gene actions were significant for all characters except total nitrogen content and dominance gene effects were also significant for all characters. Yield, number of leaves per plant, leaf length and leaf shape index were inherited as partial dominance, and overdominance was detected for plant height, stem diameter, internode length, total alkaloid, total nitrogen and total sugar content. Dominant gene showed increasing effects in yield, plant height, stem diameter, internode length, leaf width and total sugar content, but showed decreasing effects in the other characters. The broad heritability was very high for all characters. and the narrow heritability was high in days to flower and yield, but low in internode length, total alkaloid, total nitrogen and total sugar content.

• Journal of the Korean Ceramic Society
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• v.44 no.2 s.297
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• pp.103-109
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• 2007

In this study, the rheological properties of cement pastes containing blastfurnace slag of different fineness were investigated. The fluidity of cement pastes with low Blaine value blastfurnace slag was increased with decreasing the plastic viscosity and the yield stress of pastes. And the optimum dosage of polycarboxylate type superplasticizer to the cement pastes was confirmed according to the fineness and the replacement ratio of blastfurnace slag. All cement pastes showed the thixotropy behavior. And also it was formed that the segregation range of cement pastes was occurred below $10D/cm^2$ of the yield stress and below 350 cPs of the plastic viscosity by the coaxial cylinder viscometer.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.52 no.1
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• pp.100-103
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• 2007

A field experiment was conducted in Agronomy farm at an altitude of 1350 m. above sea level in a randomized complete block design with three replications and eight treatments on vegetable type soybean in 2005. The objective was to see the effect of vermicompost alone and in combination with Rhizobium inoculum and mineral fertilizers on the yield of vegetable soybean. The result showed higher number of nodules from the non inoculated plot, however, the nodules weight was highest from the inoculated plots. No significant difference was notice statistically on roots and shoots dry weight. Soybean grain was obtained highest (32.3%) over the non inoculated plot followed by vermicompost plus inoculated, however, there was non significant difference. There was a slight increment on grain and straw yield from the inoculated plots over the non inoculated.

• Proceedings of the Korean Society of Agricultural Engineers Conference
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• 1998.10a
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• pp.349-352
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• 1998

In many circumstances, it is infeasible to simulate the daily water yield in every land use or soil type of the watershed or river basin. These situations can be simulated in“Soil and Water Assessment Tool”(SWAT) using a concept called“hydrologic response units”(HRU's) within a topographically-defined subbasin. Soil water balance, crop growth, nutrient cycling management, etc., are simulated for each HRU For the watershed of Bok-ha river, the effect of HRU's in SWAT has been studied in respect to water yield. The optimum number of HRU's was 23 based in data capacity and correlation coefficient.

• The Korean Journal of Food And Nutrition
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• v.9 no.4
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• pp.409-412
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• 1996

본 연구는 '96학년도 배재대학교 교내 학술 연구비 지원으로 수행되었다. ^x Juice yield of peach "Yoo Myung" by pretreatment of various enzymes and heat was determined, and physicochemical properties of peach wine fermented by some Saccharomyces cerevisiae were also investigated. 89.2% of juice yield was showed in mixture treatment of pectinase and cellulase at 35$^{\circ}C$ for 8 hrs, 82% of yield was also showed in single treatment of pectinase and cellulase. Ethyl alcohol content of peach wine fermented by wild type Saccharomyces cerevisiae 49-2 was 14.55. However, wine from thermophilic Saccharomyces cerevisiae D-71 was excellent in taste and flavor.nd flavor.

• Journal of the Korean Society of Clothing and Textiles
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• v.28 no.7
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• pp.1029-1036
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• 2004

The fragrant fabrics were prepared by treatment with eucalyptus microcapsules. 100% cotton fabric, 100% polyester fabric and 100% wool fabric were used as test specimens. Using pad-dry-cure method, microcapsules were attached on each specimen by acrylic binder under conditions of varying concentration. Surface property, stiffness, and air permeability of fragrant fabrics were evaluated. As increasing concentration of binder, add-on yield was increased. Add-on yield was decreased with increasing laundering cycle, especially in polyester fabric. As the concentration of binder was increased, the properties of stiffness and air permeability were decreased. Also it fumed out that pad-dry-cure method was not suitable to polyester fabric.