• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 1999.08a
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• pp.188-197
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• 1999

Grain refinement of the structural steels was selected as the most effective method to meet improvement of strength and toughness without heat treatment. So, the future research and developing direction of ultra fine grain steels are more and more required to response to the production of eco - materials(environmental consciousness - materials) In this paper, the product of surface fine grain steels by CRCT and Inverse Transformation Method by warm deformation of martensite is carried out in order to improve the production process of Dowel Bar. It is possible to obtain surface ultra fine grain steel, when warm deformation of martensite formed after quenching is carried out from 730$^{\circ}C$ to 800$^{\circ}C$ in the finishing rolling step. The characters of surface with ultra fine grain steel is showing the cementite particles inside the ferrite grain and fine ferrite grain of about 1.2$\mu\textrm{m}$ in size.

• Proceedings of the Korean Society of Organic Agriculture Conference
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• 2001.10a
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• pp.192-206
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• 2001

A major challenge in the transition from conventional to organic production in a grain intensive region such as the Com Belt legion of the U.S.A. is how to profitably select and manage a crop relation. The opportunity cast of forgoing grain production for forage and green manure crops is significant. Many organic researchers and writers emphasize the need to bring an animal enterprise into the farming system for diversification and enhanced labor utilization. Livestock also add value to grain and forage crops to offset decreased grain production and can recapture nutrients used in crop production that can be recycled through manure. In grain intensive regions, organic farmers should consider swine production as a natural fit for the farming system. Swine are very efficient and adaptable animals that can add value to both grain and forage crops. While somewhat lacking, there is a reasonable body of literature on organic and sustainable swine production. However, there is relatively little specific information available to organic farmers to assist in the initial decision to enter organic swine production and to evaluate marketing alternatives. The primary focus of this paper is to give some background on organic animal production(emphasis on swine) in the Central United States and outline production and marketing decisions and considerations, relative to market trends, demographics and standards(U.S.). At the farm level, decisions must be made regarding resources, such as land, labor, financial and social capital, all relative to opportunities, all in the context of the standards and market forces beyond the farm. At the personal level the farmer must also make decisions about convictions regarding organic or environmentally friendly agriculture, willingness to change, impacts on lifestyle and family, and the transition to organic methods within the planning horizon of the farmer and the family business.

• Asian-Australasian Journal of Animal Sciences
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• v.18 no.3
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• pp.340-344
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• 2005

In high-income Asian countries like Korea and Japan, per capita rice consumption has declined because of the change in consumer' favorite foods from rice to high-cost quality foods. This has forced farmers to reduce rice production. Although fodder rice could be another option to be cultured by farmers, available information concerning rice grain silage has been limited. In the present study, therefore, the difference in the quality of fodder rice silage prepared from either whole crop or grain at different ripening stages was compared. Various supplements were also added into whole crop and grain silages of fodder rice before ensiling, and thereafter, the palatability of prepared silages was determined by beef cattle. At ear emergence stage, the pH values for both grain and whole crop silages were approximately 4.5. In both grain and whole crop silages, the pH values were significantly increased by progressing ripening stages from milk-ripe stage to yellow-ripe stages, and the increase in pH value for grain silage was faster than that for whole crop silage. In the grain silage, the higher lactic acid (LA) content in grain silage seemed to be, the lower pH value was. Both in grain and whole crop silages, pH was significantly decreased by supplementation with LA bacteria. There were no significant differences in feed intake among any treatment groups.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2010.11a
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• pp.205-209
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• 2010

The technology of production of the thermoplastic composite rocket propellants is based on a two-phase production procedure. The first phase represents the production of a semi-product in the sheet (foil) form (thickness: 0.5 mm ~ 5 mm), whereas the second phase is realized independently from the first one and it is based on the semi-produced product and thus the final form of the propellant grain is realized in relation to the defined geometry. Well done mechanical characteristics of the propellant grain enable that the same thing could be used as a mandrel in the filament winding procedure in creating the motor chamber of the composite material.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.36 no.4
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• pp.294-299
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• 1991

Eight naked barley cultivars were grown in three production systems to select proper cultivars for dual production of forage and grain and to determine production system x cultivar interactions. In the forage systems. barley was seeded on September 27 and October 17, harvested for forage on November 1. December 10 and February 12 from the September 27 planting (forage system I) and on December 10 and February 12 from the October 17 seeding(forage system II). In the grain-only system, barley was planted on November 5. In forage system I, oven-dried forage yields of eight cultivars ranged 195 to 296kg/10a and Saessalbori and Naehanssalbori yielded significantly higher than the other cultivars recording 280 and 296kg/ l0a, respectively. In forage system II, oven-dried forage yields of eight cultivars ranged 106 to 143kg/10a showing no significant difference among cultivars. Production system x cultivar interactions were significant for lodging at maturity, powdery mildew rating, 1000 kernel weight and grain yield. Leaf area index and biomass at heading, no. of spikes per $m^2$, no. of kernels per spike and test weight were not affected by the production system. Forage utilization delayed heading by 3 days and reduced culm length, spike length, lodging due to heavy rain on May 5 and lodging at maturity except for Songhagbori and Naehanssalbori. Forage utilization did not significantly affect grain yield from the September 27 planting but reduced 9% from the October 17 planting. while Saessalbori and Hyangcheonggwa 1 yielded significantly less than in the grain-only system. Songhagbori appears to be a proper cultivar for dual production of forage and grain in Cheju, considering forage and grain yields. and lodging and powdery mildew resistance.

• Asian-Australasian Journal of Animal Sciences
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• v.13 no.2
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• pp.188-191
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• 2000

Appetite stimulant ether-soluble neutral extract of a high-grain compound feed was separated into four fractions with an open column of silica gel chromatograph using four carrier solutions containing n-pentane and diethyl ether as 100:0 (Fraction A), 90:10 (Fraction B), 75:25 (Fraction C) and 0:100 (Fraction D). The stimulative effects of the fractions were examined by comparing the intake of hay (with or without the fractions) in two-choice test bioassays with cattle. The Fractions A, B and C of the neutral extract stimulated (p<0.05) hay consumption in cattle, whereas Fraction D had no effect on selective feeding when compared with the control fraction. Furthermore, Fractions A, B and C had higher (p<0.05) feeding stimulative indices (FSI) than that of the Fraction D. The results suggest that chemical stimulants to increase palatability of hay are present in the neutral Fractions A, B and C of high-grain concentrate.

• Journal of Animal Science and Technology
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• v.61 no.1
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• pp.18-27
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• 2019

With South Korea's limited capability of feed production because of its relatively small cultivable area, the country is pushed to depend on foreign feed imports despite the immensely fluctuating price of corn. Hence, intensive efforts to increase the total cultivable area in Korea like extending of farming to mountainous area is being practiced. Corn was planted in Goesan County, a mountainous area in the country. Grain and stover were harvested separately in three harvest periods: early-harvest (Aug 8), mid-harvest (Aug 18), and late-harvest (Aug 28). The nutrient composition such as dry matter (DM), crude protein (CP), crude fat (EE), organic matter (OM), neutral detergent fiber (NDF), acid detergent fiber (ADF), and non-fibrous carbohydrates (NFC) was determined after harvest. Effective degradability (ED) of the major nutrients (DM, NDF, ADF, and CP) were measured through in vitro fermentation of rumen fluid from Hanwoo (Korean cattle). pH, ammonia-N concentration, volatile fatty acid (VFA) concentration, and gas production were periodically measured at 0, 3, 6, 12, 24, 48, and 72 h. Corn grain showed higher nutrient content and ED than stover. It also had higher gas production but its pH, ammonia-N, and total VFA concentration were lower than corn stover. The best nutrient composition of corn grain was observed in early-harvest (high CP, EE, NDF, OM, NFC, and low ADF). Early-harvest of corn grain also had high effective degradability of dry matter (EDDM), effective degradability of neutral detergent fiber (EDNDF), effective degradability of acid detergent fiber (EDADF), and total VFA concentration. On the other hand, the best nutrient composition of stover was observed in mid-harvest (high DM, CP, NDF, and low ADF). EDDM, EDNDF, and EDADF were pronounced in early-harvest and mid-harvest of stover but the latter showed high total VFA concentration. Hence, early and mid-harvested corn stover and grain in a mountainous area preserved their nutrients, which led to the effective degradation of major nutrients and high VFA production.

• 한국초전도학회:학술대회논문집
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• 2008.08a
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• pp.87-87
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• 2008

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 1993.10a
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• pp.158-173
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• 1993

The formulated mechanization packages for grain maize production have performed to the expected limit generating encouraging information. Besides physical feasibility , management factors viz ; production operation sequence, operations scheduling and machinery matching with respect to environment can still limit system suitability. A new production operation sequence was introduced to overcome weed problems and limitations of available working days. Proper operations scheduling will improve the initial soil-crop environment for better seedling establishment, and reduce the (). been identified as key factors to reduce capital investment and cost of proudction .

• KOREAN JOURNAL OF CROP SCIENCE
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• v.8 no.1
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• pp.1-4
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• 1970

To study the varital response of grain, protein and oil yield to different sowing dates and calcium levels in soybean, the most important crop as a protein source in Korea, this experiment was conducted in 1969. Three leading soybean varieties (Choongbukbaek, Ryooku＃3 and Changdanbaekmok) were sown at May 22,, June 11 and July 1 under 3 different calcium levels, 0.50 and 100kg per 10a respectively. The results are summarized as follows: 1. Ryonku ＃3 showed the highest grain yield because of the highest number of pods per hill. In order of protein content, and oil content of grain, Choongbukbaek>Ryooku＃3>Changdanbaekmok and Changdanbaekmok>Choogbukbaek>Ryooku＃3 were found. Ryooku＃3 also showed the highest protein and oil production per unit area owing to the highest grain yield. However. varietal differences of the grain yield the protein and the oil production per unit area varied along the different sowing dates. Interactions between varieties and sowing date on the grain yield should be considered in practice. 2. No difference in the grain yield was found between the first sowing date (May22) and the second (June11) on average. The grain yield in the plot of the third sowing date (July l)was strikingly decreased mainly by the smaller number of pods per hill. The protein and the oil content were not varied significantly by the different sowing dates. The protein and oil production per unit area were lowest in the plot of the third sowing date owing to the decreased grain yield. 3. More calcium application increased the number of branches per hill, the number of pods per hill, and the grain yield. The highest grain yield was found in the plot received 100 kg of calcium hydroxide per 10are. Protein content increased in higher calcium level, but oil content was highest in the plot of noncalcium. More protein production per unit area was gotten by more calcium application because of higher grain yield and protein content. all production increased in higher calcium level by the increased grain yield. 4. High plus (+) correlation was found between stem length and stem weight per hill stem length and grain weight, stem length and grain yield, stem weight per hill and number of pods per hill and grain weight, number of branches per hill and grain weight, number of pods per hill and grain yield, and grain weight and protein content of grain. Minus(-) correlation was recognized between number of pods per hill and grain weight.