• Journal of The Korean Society of Grassland and Forage Science
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• v.42 no.4
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• pp.243-248
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• 2022

This study was conducted to evaluate the effect of feeding the whole crop rice silage (WCRS) which partially replaces the imported grass hay crop on the milking performance of Holstein and profitability. Two experimental diets were used according to the traditional practice of dairy farms. The control diet (C) was composed of 13kg/day of mixed hay, 6.8kg/day concentrate, and orchardgrass/bermudagrass hay (1.8kg/day). The treatment diet (T) was composed of 9.6kg/day of mixed hay, 6.8kg/day of concentrate and 2.2kg/day of WCRS. The CP content of the WCRS (4.6%) was lower than orchardgrass (11.3%) and bermudagrass hay (8.4%) due to the harvest being 30days later than the optimum harvest date of rice. The lower intake was observed in T during the entire experiment period which seems to be related to the higher proportion of fiber in rice (p<0.05). No significant difference was found in milk production between C (26.9kg) and T (26.3kg) during the entire experiment period (p>0.05). Also, no difference in milk fat, milk protein, total solids, and milk composition was observed between the two diets. Higher income per head was resulted in T (21,141won) compared to C (21,915 won). These results indicate that the partial replacement of the grass hay by the WCRS can bring the profit to the dairy farm due to the no difference between the control diet and the treatment diet.

• 한국신재생에너지학회:학술대회논문집
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• 2010.06a
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• pp.131.1-131.1
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• 2010

고분자연료전지(PEMFC)에서 기체확산층(GDL)은 다공성의 카본 종이/천 위에 마이크로한 다공층을 가치는 구조로 촉매층을 지지하고 촉매층과 분리판 사이의 전류전도체 역할을 한다. 또한 촉매층에 연료와 공기 확산 및 생성된 물의 통로 역할을 하며 소수성인 전기전도성 물질로 이루어져 있다. 현재 연료전지에 쓰이는 가스확산층은 대부분 국외 회사에서 제조 수입 사용하는 현황이고 국내에서는 협진 I&C가 연구하고 있으나 상용화는 아직 이루어지지 않고 있다. 본 연구는 탄소섬유의 전도성을 개선하고자 탄소섬유 표면에 금속코팅 시 최적의 접촉계면유지를 위한 표면처리 방법 및 공정을 조사 분석 후 최적 개선방법(농도/온도/압력/시간)을 설정하고자 하였다. 또한 선정된 공정인자별 수준별 시험 후 샘플링 된 시료를 토대로 금속물질이 탄소섬유 표면에 코팅(도금)된 금속-탄소섬유를 대하여 평가하여 최적화시키고자 탄소섬유로부터 carbon paper GDL의 모재를 개발할 계획이다. 앞에서 설명한 바와 같이 탄소섬유를 이용하여 paper making, resin impregnation, molding, carbonization/graphitization의 제조공정을 거쳐 paper형태의 GDL을 생산 및 평가하고자 하였다.

• Proceedings of the Korea Technology Innovation Society Conference
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• 2015.11a
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• pp.884-906
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• 2015

본 연구는 공공연구기관의 기술이전 효율성을 분석하기 위해 효율성 분석기법인 DEA를 활용하였다. 투입요소로 연구비, 연구인력, TLO 인력, TLO 운영비 네 가지를, 산출요소로 기술이전 계약건수, 기술이전 수입료 두 가지를 선정하여 기술이전 효율성을 산출하였다. 기술이전 효율성에 영향을 미치는 변수로 지역적 위치, 연구기관 유형, 민간부문 연구개발비 비중, 인센티브 제도 등을 고려하여 산출된 효율성을 비교하였다. 본 연구의 분석을 통해 다음의 4가지 시사점을 도출하였다. 첫째, 연구기관 지방이전 시 먼저 인프라를 구축하고 산학연협력이 제대로 이뤄질 수 있는 환경을 조성해야 한다는 것이다. 둘째, 연구기관별로 설립 목적에 맞는 R&D를 수행할 수 있도록 해야 한다. 셋째, 민간수탁 증대가 R&D 효율성(기술이전 효율성)과 직접적으로 연결이 될 거라는 단편적인 생각은 버리고 폭넓은 의견수렴과 심층적 조사가 필요하다. 넷째, 인센티브 제도나 규정을 운영함에 있어 TLO 인력에게 직접적인 동기요인으로 작용할 수 있는 장치를 만들어야 한다. 본 연구의 분석을 통해 정부 연구기관들의 기술이전 효율성에 대한 이해를 높이고, 도출된 시사점을 바탕으로 국가 R&D 체계를 개선하는데 유의미한 정책의 개발이 있을 것으로 기대한다. 또한 공공연구기관의 기술이전에 대한 관심과 논의가 확대되고, 향후 축적될 자료를 활용한 정교한 연구가 활발히 이어지기를 희망한다.

• Journal of The Korean Society of Grassland and Forage Science
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• v.32 no.2
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• pp.109-116
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• 2012

This study was carried out to determine the forage quality, production, and regrowth of Phragmites communis as a native grass according to growth stages. Experiment 1 was conducted in Ansan from May 2009 to April 2010 (7 stages), and experiment 2 was conducted in Cheonan from May to November 2011 (10 stages). In experiment 1, forage quality decreased rapidly with advance of growth from May. When harvested on late May, July, September and April of the following year, the contents of crude protein were 7.7%, 4.6%, 3.7%, and 2.2%, respectively. Relative feed value (RFV) were 80.2, 65.1, 61.8 and 52.8, and lignin contents were 7.1%, 9.9%, 12.0%, and 13.2%, respectively. In experiment 2, significantly higher forage yields were observed when harvested from late June to mid July. On the other hand, forage quality decreased with delayed harvest as was in experiment 1. Good regrowth of Phragmites communis was observed when harvested earlier than in August. When harvested on late May, June, July, August, September, October and November, the dry matter (DM) yields were 7,329 kg/ha, 12,527 kg, 9,593 kg, 8,279 kg, 7,649 kg, 5,822 kg and 5,540 kg, and in vitro digestible DM (IVDDM) yields were 3,924 kg/ha, 5,264 kg, 4,273 kg, 3,322 kg, 3,352 kg, 2,195 kg and 1,887 kg, respectively. Forage quality grades of Phragmites communis were 4th grade in May, 5th grade from June to Sept., and 6th grade in Oct., Nov., or in Apr. of the following year. However, all regrown Phragmites communis ranked the 4th in quality. In conclusion, we recommend that Phragmites communis should be harvested from late June to mid July (no later than the end of July) to obtain good forage quality with digestible nutrient contents greater than rice straw. Regrowth of Phragmites communis was poor, and more than 70% of annual forage yields were out of the first harvest. Therefore, we recommend only one harvesting per year for good regrowth and stable production of Phragmites communis.

• Journal of The Korean Society of Grassland and Forage Science
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• v.11 no.2
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• pp.68-75
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• 1991

A series of tests was carried out to determine the purity and germination of pasture plant and forage crop seeds imported in 1986 and 1987 at the grassland and forage laboratory, College of Agriculture, Seoul National University, Suweon. At the same time, the results obtained were compared with the National Livestook Cooperatives Federation(NLCF1's seed standards as a guide for determining seed quality. 1. The germination percentages of Potomac orchardgrass, Fawn tall fescue, Aquila Ky bluegrass and California ladino clover among grasses and legumes tested were lower than those of the N1,CF's standards, but the germination percentages of forage crops were higher than those of the NLCF's standards. 2. The purity of Potomac orchardgrass and Aquila Ky bluegrass were relatively lower than those of the NLCF's standards. 3. The percentages of other crop seeds in Potomac orchardgrass, Fawn tall fescue, Aquila Ky bluegrass and Cayuse oats were lower than those of the NLCF's standards. 4. Percentage of inert matter in the seeds was lower compared with the NLCF's standards except Akela ' forage rape. 5. The seeds of Potomac orchardgrass, NK 367 sorghum hybrid and sorghum x sudangrass hybrids such as NC+855, G83F and TE Haygrazer were contaminated with one or more weed seeds. Rumex spp. was by far the most common weed in the seeds imported. The other weeds occurred at a low level were Rumex acestosella, Senecio jacobaea, Cirsium arvense and Cuscicta spp. 6. There were many variations in 1,000 seed weight among different species. A thousand seed weight of Aquila Ky bluegrass was 0.263g, but that of Tetrone Italian ryegrass, Akela forage rape and Pioneer 3160 sorghum x sudangrass hybrid was 3.875, 3.476 and 242.4578, respectively. 7. According to the fluorescence test of ryegrass seed, Tetrone Italian ryegrass was known as a true annual type, but an unknown cultivar produced in Cheju was contaminated with 6% of perennial ryegrass seed.

• Journal of Animal Science and Technology
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• v.48 no.3
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• pp.479-486
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• 2006

The current study was conducted to examine the effect of feeding and management practices on milk quality and dairy farm productivity in Korea. Fifty dairy farms in Gyunggi (11), Gangwon (22), Chungnam (17) provinces were surveyed to collect data on the herd size, housing style, feeding management, waste disposal, milking practices and milk yield. Milk tank samples from all farms under study were also collected to enumerate its composition and quality parameters. Large dairy herds are equiped with better housing, milking and waste control facilities than medium and small dairy herds. Higher concentrate feeding to lactating cows was noticed in small dairy herds (47.51 %) than in medium (32.59 %) and large dairy herds (31.82 %). The decrease in concentrate feeding to lactating cows with increase in number of cows per farm resulted in a simultaneous increase in the use of imported forages. Bacterial count in milk was affected by housing and milking facilities at dairy farms. Higher bacterial counts (Coliform and E. coli) in milk were observed in cows housed in stanchion than those under free stall with saw dust bedding. The bacterial counts were higher with bucket milking system than with pipe-line and parlour systems. The increase in the number of dairy cows per farm and thus better management and milking facilities resulted in a reduction in somatic cell score. Milk yield (per cow) was higher in herds with less somatic cell score. Average milk protein concentration was between 2.89 to 2.98 % and milk urea nitrogen was between 21.81 to 23.31mg/ml on surveyed dairy farms. This study concluded that large herd size with better dairy cow management facilities is crucial to produce quality milk with better dairy farm income.

• Korean Journal of Food Science and Technology
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• v.40 no.4
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• pp.375-381
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• 2008

This study developed the simultaneous analysis method for efficient safety controls of import food of Orange II, Rhodamine B, Para Red, and Sudan dye I-IV among disapproved coloring agents that use is prohibited in foods. The analysis method was developed according to the sample pre-treatment and HPLC conditions, and a documentary survey was used to establish the detection limit of the method, followed by effectiveness verification and recovery percentage examinations. Recovery percentage examination for 26 products resulted Orange II displayed recovery percentage of 96.46-121.26%, Rhodamine B displayed recovery percentage of 70.86-106.53%, Para Red displayed recovery percentage of 97.00-116.86%, Sudan I displayed recovery percentage of 92.93-112.44%, Sudan II displayed recovery percentage of 96.63-115.10%, Sudan III displayed recovery percentage of 92.21-114.73%, Sudan IV displayed recovery percentage of 93.22-122.91%. Correlation coefficient of gradient of this analysis method exhibited more than 0.999, RSD exhibited fewer than 2 as 0.8-1.39%, exactitude exhibited more than 90%. At this time, detection limit and fixed quantity limit decided by each 0.1 mg/L, 0.3 mg/L.

• Journal of The Korean Society of Grassland and Forage Science
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• v.29 no.1
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• pp.63-72
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• 2009

The experiment was conducted from 2007 to 2008. The experimental roughages include five sources and 25 species in all; grasses and legumes: 5 species (mixed grasses, orchardgrass, tall fescue, alfalfa, white clover), native grasses and weeds: 5 species (mixed native grasses, Miscanthus sinensis Anderss, Arundinella hirta (Thunb.) Tanaka, barnyard grass, short awn, forage crops and straw: 5 species (barley 4- hairy vetch, wheat 4- hairy vetch, rye silage, barley silage, baled rice straw), browse and fallen leaves: 5 species (mixed browse, oriental white oak browse, Quercus serrta Thunb., browse oriental cherry fallen leaves, Japanese chestnut fallen leaves), and imported hay and straw: 5 species (timothy hay, tail fescue straw, annual ryegrass straw, klinegrass hay, alfalfa hay). Ten dairy goats (Saanen) were selected which had nearly the same body weight (25kg). The experiment was carried out on the dairy goats farm at Geumsan-Cun in Chungnam province. The chemical composition and dry matter digestibility of each roughage source and species were significantly different at the sampling area, plant species, growth stages and cutting period. Among all the 25 species of roughages, the favorite intake species order by dairy goats was observed like this: mixed grasses, white clover, alfalfa and the lower intake species order was baled rice straw and rye silages. The dairy goats ate more roughages which had low fibrous contents, but high dry matter digestibility. On the other hand, compared to each roughage source, the goat's favorite roughage were grasses and legumes (34.6%) among the trial species. Based on the result, it is reconfirmed that the food habit of dairy goats seems to be closer to that of graters.

• Journal of The Korean Society of Grassland and Forage Science
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• v.22 no.4
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• pp.247-252
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• 2002

“DK 537”has been selected by forage crop breeding team at the National Livestock Research Institute(NLRI), RDA and has been determined by the Deliberative Council of the National Agricultural Cooperative Federation(NACF) in 2002, as a new recommended hybrid which is early maturing, good quality and hi호 yield of corn for silage. The characteristics of this hybrid are as follows ; 1. The seed coat is yellow and the mean of tasseling date is 5th of July, included in early maturing hybrid which is one day delayed than check cultivar, DK 501. The culm length is 246cm. It is resistant to lodging because of its low height from surface to ear. 2. DK 537 shows resistance to H. maydis and Maize Black-Streaked Dwarf Virus(MBSDV). It also shows strength to corn borer as much as DK 501 does. 3. Fresh yield. dry matter yield. and TDN per a ha are 50 tons, 16.9 tons, and 11.4 tons respectively. which are almost same yielding level of DK 501. Its percent ear to total dry matter is 50.8% at the same time. Through all these tests, we could make sure at DK 537 hybrid will be recommended as good forage crop.

• Journal of The Korean Society of Grassland and Forage Science
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• v.37 no.2
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• pp.168-175
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• 2017

Single nucleotide polymorphisms (SNP) markers allow rapid screening of crop varieties in early growth stages. We developed a modified SNP PCR procedure for assaying SNPs in maize. For SNP marker development, we chosen 200 SNP sites from MaizeGDB database, and designed two base pair mismatch primers based on putative SNP site of B73 genome sequence. PCR products size was from 200 to 500 bp or was not shown in the case of SNP site existing in Korean silage corns. Using previously discovered 16 primer sets, we investigated distinctness of 50 silage F1 hybrid corns including 10 Korean silage corns developed by RDA such as Gangdaok, Kwangpyeongok, Dapyeongok, Andaok, Yanganok, Singwangok, Jangdaok, Cheongdaok, Pyeonggangok, and Pyeonganok as well as 40 foreign commercial silage corns. From cluster analysis, we confirmed that 10 Korean silage F1 hybrid corns were clearly distinguished except for Singwangok, P1395, and several foreign commercial corns, and selected minimum SNP primer combination for Gangdaok, Jangdaok, Pyeonggangok, and Pyeonganok. Therefore, development of SNP marker sets might be faster, cheaper, and feasible breed discrimination method through simple PCR and agarose gel electrophoresis.