• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 1999년도 제3회 압연심포지엄 논문집 압연기술의 미래개척 (Exploitation of Future Rolling Technologies)
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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.

• 한국유기농업학회:학술대회논문집
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• 한국유기농업학회 2001년도 심포지엄
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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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• 제18권3호
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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.

• 한국추진공학회:학술대회논문집
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• 한국추진공학회 2010년도 제35회 추계학술대회논문집
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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.

• 한국작물학회지
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• 제36권4호
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• pp.294-299
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• 1991

제주지방에 있어서 청초 및 종실 겸용재배에 알맞은 쌀보리 품종을 선발하고 재배유형과 품종과의 상호작용을 구명하고자 8개의 국내 장려품종을 종실단용구(11월 5일 파종), 겸용재배구 I (9월 27일 파종 ; 11월 1일, 12월 10일, 2월 l0일 예취), 겸용재배구 II(10월 17일, 파종； 12월 10일, 2월 10일 예취)에서 각각 재배하여 건초수량, 예취 후 생육, 종실수량 등을 조사한 결과를 요약하면 다음과 같다. 1 겸용재배구 I의 평균 건초 수량은 195-296 kg/10a이었고 새쌀보리와 내한쌀보리의 건초 수량이 280, 296kg/10a으로 다른 품종보다 많았으나 겸용재배구 II의 평균 건초수량은 106-143kg/10a으로 품종간 유의한 차이가 없었다. 2 성숙기, 도복정도, 흰가루병 이병정도, 천립종, 종실수량은 품종과 재배유형간의 상호작용이 유의하였고 출수기, 엽면적지수와 건물중, $m^2$당 수수, 수당 입수, 1ι중은 재배유형간에 차이가 없었다. 겸용재배구 I, II에서 종실단용구에 비하여 출수가 3일 늦어 졌고 간장과 수장이 단축되는 경향이었다. 3. 5월 6일 비바람에 기인되었던 도복은 겸용재배구 I에서 적었다. 성숙기 도복은 송학보리와 내한쌀보리를 제외하고는 겸용재배구 I, II에서 적었다. 흰가루병 이병정도는 내병성 품종에서는 재배유형간 차이가 없었지만 이병성 품종에서는 겸용재배구 I, II에서 적었다. 4 8개 품종 평균 종실수량은 종실단용구와 겸용재배구 I 에서 각각 352, 344kg/10a로 비슷하였으나 겸용재배구 II에서 종실단용구에 비하여 9% 감소하였다. 겸용재배구 II에서만 새쌀보리와 향천과 001의 종실수량이 종실단용구에 비하여 유의성 있게 적었다. 5. 건초 및 종실수량, 도복 등을 고려하여 볼때 겸용재배에 적합한 품종은 송학보리였다.

• Asian-Australasian Journal of Animal Sciences
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• 제13권2호
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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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• 제61권1호
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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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• 한국초전도학회 2008년도 High Temperature Superconductivity Vol.XVIII
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• pp.87-87
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• 2008

• 한국농업기계학회:학술대회논문집
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• 한국농업기계학회 1993년도 Proceedings of International Conference for Agricultural Machinery and Process Engineering
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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 .

• 한국작물학회지
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• 제8권1호
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• pp.1-4
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• 1970

단백자원으로서 가장 중요한 작물인 대두의 자실수량, 단백 및 유분수량이 품종별로 파종기 및 석회시용량의 차이에 따라서 어떻게 영양을 받는가를 구명하기 위하여 우리나라 중부지방의 주요대두품종 충북백, 육우 003 및 장단백목을 공시하여 파종기를 5월 22일(대두단작재배) 및 6월 11일(맥후작재배) 및 7월 1일 (만파재배)로 달리하고 석회시용량을 10a당, 0.5kg, 100kg으로 다르게 처리하여 본 시험을 1969년 서울대학교 농과대학 부속농장에서 실시하였다. 본 시험성적에서 나타난 대두의 수량형질, 단백 및 유분수량에 대한 결과를 요약하면 다음과 같다. 1. 공시된 품종중 육우003의 자실수량이 가장높았다는데 이는 육우003에 주당협수가 다른 품종보다 현저히 많다는 데에서 기인되었다. 단백함량은 충북백>육우003>장단백목의 순위였고 지유함량은 장단백목>충북백>육우003의 순위였으나 단위면적당 단백수량 및 지유수량은 자실수량이 많았던 륙우003가 가장 많았다. 그러나 이와같은 품종간 수량차이는 파종기에 따라서 각각 다르게 나타나고 있으므로 설계재배에 있어서는 품종과 파종기간의 관계를 크게 고려하여야 할 것이다. 2. 제1파종기와 제2파종기간에 자실수량차이는 없었으며 만파재배인 제3파종기에서는 자실수량이 현저히 감소되었다. 이와같은 현상은 제3파종기에서 1주당협수의 감소가 현저했기 때문으로 고찰된다. 단백질함량과 지유함량은 파종기에 따라 별로 변화하지는 않았으나 단백수량 및 지유수량은 제3파종기에서 자실수량의 감소와 함께 현저히 감소하였다. 3. 석회시용량의 증가에 따라서 분지수 협수가 증가하였으며 자실수량도 증가하였다. 본 시험에서는 자실수량이 석회 100kg/10a 시요구에서 가장 높았다. 단백함량도 석회시용량을 증가함에 따라 증가하였으나 지유함량은 석회무시용구가 가장 높았다. 단백수량은 석회시용량의 증가에 따라 자실수량 및 단백함량이 같이 증가되었기 때문에 현저히 증수되었으며 지유함량은 자실수량의 증가에 의해서만 증수되었다. 4. 수량형질간의 상관관계를 보면 경장과 주당경중, 100립중 및 자실수량간에 주당경중과 주당맥수 및 자실수량간에, 주당분지수와 100립중간에, 주당협수와 자실수량간에, 100립중과 단백함량간에는 고도의 정(+)의 상관관계를 인정할수 있었으며, 주당협수와 100립중간에는 부(-)의 상관관계가 있었다.