• 제목/요약/키워드: Agricultural R and D

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실부하 적용을 통한 농용 트랙터 변속기 해석 (Analysis of Agricultural Tractor Transmission using Actual Farm Workload)

  • 김정길;박진선;최규정;이동근;신민석;오주영;남주석
    • 한국기계가공학회지
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    • 제19권11호
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    • pp.42-48
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    • 2020
  • The agricultural tractor is a multi-purpose vehicle, which is frequently used in the agricultural field. It must be highly reliable in terms of human safety. Design and analysis of agricultural tractors must be performed using actual agricultural workload to maintain high reliability. Additionally, the frequency with which various components and systems are used must also be taken into consideration. In this study, a tractor is built to measure its workload in the actual field. Further, the measured load was analyzed for various farming tasks. The range of ratios of consumed power to engine power was measured to be 42.6%-87.2%, 75.1%-97%, 26.5%-59.2% for a plow, rotary, and harvest tasks, respectively. The results were fed into a transmission simulation model to analyze the strength and life of the transmission components. We conclude that a more reliable product can be constructed by incorporating the transmission analyses using the actual load.

곤충세포 배지 개발을 위한 체액산화지연 돌연변이 누에계통 선발 (Selection of Mutant Silkworm with Oxidation-deficient Haemolymph for Insect Cell Culture)

  • 최지영;김종길;최영철;윤형주;안미영;김삼은;황석조
    • 한국잠사곤충학회지
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    • 제49권2호
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    • pp.47-50
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    • 2007
  • 누에 체액은 공기 중의 산소와 접하게 되면 도파퀴논(dopaquinone)이라는 세포 성장을 저해하는 물질을 생성하게 된다. 체액의 산화를 방지하기 위해서는 일반적으로 열처리에 의해서 효소를 불활성화 시키는 방법이 이용되고 있으나 대량 채혈 시에는 열처리 이전에 이미 산화가 진행되는 문제점이 있다. 이러한 문제점을 해결하기 위하여 누에 중 체액 산화가 더디게 진행되는 누에 계통을 선발하게 되었다. 누에체액을 채취하여 경과시간별로 산화정도(변색)를 육안으로 확인하여 TBO, $Y_4$, 백안$E^b$과잉지 3품종을 선발하고 spectrophotometer를 이용하여 산화반응 속도를 측정하였다. 백옥잠 체액과 각각의 산화지연 누에 체액의 산화속도를 400 nm에서 측정한 결과 백옥잠은 120분인데 비하여 체액산화 지연계통인 $Y_4$는 330분, TBO는 360분 그리고 백안$E^b$과잉지는 450분에 산화가 완료되었다. 산화지연 누에계통의 체액의 곤충세포 증식에 미치는 영향을 조사한 결과 대규모 채혈한 체액산화지연 계통의 체액은 야성형 계통(백옥잠)에서 소규모 채취한 체액에는 미치지 못하였으나 대규모 채취한 체액보다는 우수하였다.

Cultural Characteristics of Veiled Lady Mushroom, Dictyophora spp.

  • Cheong, Jong-Chun;Kim, Gwang-Po;Kim, Han-Kyoung;Park, Jeong-Sik;Chung, Bong-Koo
    • Mycobiology
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    • 제28권4호
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    • pp.165-170
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    • 2000
  • This study was carried out to obtain the basic data for artificial culture of veiled lady mushroom (Dictyophora spp). The optimal conditions for the mycelial growth were $25^{\circ}C$ and pH 5.0 for all isolates except the optimal temperature of $30^{\circ}C$ for D. echinovolvata ASI 32002 and Phallus rugulosus. The optimal medium for Dictyophora spp. was PBA (potato bamboo sawdust extract agar) medium. The strain ASI 32002, D. echinovolvata, grew faster than. D. indusiata ASI 32003 and Phallus rugulosus ASI 25007 on the medium. Carbon sources such as glucose, maltose and inuline were favorable for stimulating a mycelial growth of the two strains of ASI 32002 and ASI 32003. Asparagine and glutamine appeared to be favorable to the strain ASI 32002 and ASI 32003, where as alanine, one of nitrogen source also favorable to the strain ASI 32002. The optimum C/N ratio of the two isolates of ASI 32002 and ASI 32003 was about 25 : 1 when 2% glucose as carbon source was mixed with the basal medium. While, in the case of 4% as carbon source, the optimum C/N ratio was about 30 : 1.

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Taxonomic Studies on the Genus Crepidotus in Korea

  • Han, Sang-Kuk;Soek, Soon-Ja;Kim, Yang-Sup;Jung, Sun-A;Jang, Hae-Jung;Sung, Jae-Mo
    • Mycobiology
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    • 제32권2호
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    • pp.57-67
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    • 2004
  • For investigation of the species diversity of the Genus Crepidotus in Korea and constructing a key to Korean Crepidotus species, a total of 65 specimens, collected from 18 locations from 1982 to 2002, were observed for morphological characters of carpophores and other features. All the specimens have been preserved in the herbarium of the National Institute of Agricultural Sciences and Technology, R.D.A., Suwon, Korea. The specimens were identified according to the classification systems given by Hesler and Smith(1965), Nordstein(1990), Orton(1960), Pilat(1948), Senn-Irlet(1991, 1992, 1993) and Singer(1951, 1973, 1986). In this study, a total of 10 Crepidotus species were confirmed. Among them, Korean common names were designated to six unrecorded species as follows: C. uber, "끈적귀버섯"; C. hygrophanus, "곤약귀버섯"; C. latifolius, "꼬마무리귀버섯"; C. obscurus, "먼지귀버섯"; C. subverrucisporus, "분홍주름귀버섯"; and C. circinatus, "노란고리귀버섯". A key to 10 Crepidotus species has been constructed.

Stereospecific Synthesis of the (2R,3S)- and (2R,3R)-3-Amino-2-hydroxy-4-phenylbutanoic Acids from D-Glucono-δ-lactone

  • Lee, Jin Hwan;Kim, Jin Hyo;Lee, Byong Won;Seo, Woo Duck;Yang, Min Suk;Park, Ki Hun
    • Bulletin of the Korean Chemical Society
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    • 제27권8호
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    • pp.1211-1218
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    • 2006
  • The enantiomerically pure (2R,3S)- and (2R,3R)-3-amino-2-hydroxy-4-phenylbutanoic acids (AHPBA) 1 and 3 are readily obtained from D-glucono-a-lactone. Both AHPBAs are the structural key units of KMI derivatives which are the potent inhibitors of BACE 1 ($\beta$-secretase) and HIV protease. Additionally, the obtained AHPBAs 1 and 3 are converted to dipeptides of bestatin stereoisomers 2 and 4.

Genetic Variability and Phylogenetic Relationship Among Proton-Beam-Irradiated Strains of Pleurotus ostreatus

  • Kwon, Hye-Jin;Park, Yong-Jin;Yoo, Young-Bok;Park, Soon-Young;Kong, Won-Sik
    • Journal of Microbiology and Biotechnology
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    • 제17권6호
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    • pp.1041-1044
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    • 2007
  • To assess the effects of a proton beam on oyster mushrooms (Pleurotus ostreatus), the genetic diversity and phylogenetic relationships among strains induced by a proton beam were investigated based on a clustering analysis. According to an AFLP DNA polymorphism analysis, the induced strains were divided into four groups that coincided with the dose. When applying proton-beam radiation, the dissimilarity among the induced strains increased when increasing the dose. When using more than 400 Gy, the genetic dissimilarity of the irradiated strains was 46-58%. Thus, evaluating the induced strains using the AFLP technique was effective in revealing the mutation effect of the proton beam.

Taxonomic Study on Volvariella in Korea

  • Seok, Soon-Ja;Kim, Yang-Sup;Won, Hang-Yeon;Lee, Kang-Hyo;Park, Ki-Moon;Min, Kyong-Hee;Yoo, Kwan-Hee
    • Mycobiology
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    • 제30권4호
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    • pp.183-192
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    • 2002
  • Diversities of Korean species belonging to the genus Volvariella have been studied through forty five dried specimens collected throughout the Korean peninsula for 28 years, from 1972 to 2000, and preserved in NIAST's herbarium. We have found one unrecorded species of the genus Volvariella in Korea: V. villosavolva(Lloyd) Sing, Stirp Taylori Korean common names were designated. Ten species of the genus Volvariella including the recorded Korean species of Volvariella have been identified and the keys to the species were constructed.