• Title/Summary/Keyword: Agricultural R and D

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Analysis of the PTO Driveline Rattle Noise on an Agricultural Tractor (농업용 트랙터 PTO 전동라인의 래틀 소음 분석)

  • Ahn, Da-Vin;Shin, In-Kyung;Han, Hyun-Woo;Son, Gwan-Hee;Park, Young-Jun
    • Journal of the Korean Society of Manufacturing Process Engineers
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    • v.18 no.6
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    • pp.45-54
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    • 2019
  • In this study, we analyze the rattle noise of a power takeoff (PTO) driveline and develop a PTO driveline resonance model. We measured the rattle noise of the PTO driveline on the output shaft and, by analyzing the rattle noise in the time domain, we determine that the engine expansion stroke period matches the sound pressure of rattle noise. This finding helped us demonstrate that the rattle noise is caused by the collision between the PTO driving gear and the gear driven by the engine expansion stroke; the torsional vibration caused by this collision is affected by the angular velocity fluctuation of the PTO drive shaft. By measuring the angular velocity of the PTO drive shaft, we confirm that the angular velocity fluctuation of the engine flywheel tends to excessively amplify the PTO drive shaft angular velocity fluctuation. We conclude that the resonance, which occurs when the operating frequency of the engine is close to the natural frequency of the tractor power transmission system, causes the excessive angular velocity fluctuation of the PTO drive shaft. We performed a modal analysis of the PTO driveline resonance and, using the characteristic equation, we show that the resonance occurs when the engine rotation speed is close to 850 rpm, which matches the natural frequency of the PTO driveline.

Expression of Antioxidant Isoenzyme Genes in Rice under Salt Stress and Effects of Jasmonic Acid and ${\gamma}$-Radiation

  • Kim, Jin-Hong;Chung, Byung-Yeoup;Baek, Myung-Hwa;Wi, Seung-Gon;Yang, Dae-Hwa;Lee, Myung-Chul;Kim, Jae-Sung
    • Journal of Applied Biological Chemistry
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    • v.48 no.1
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    • pp.1-6
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    • 2005
  • Analysis of chlorophyll (Chl) fluorescence implicated treatment of 40 mM NaCl decreased maximal photochemical efficiency of photosystem II (PSII) (Fv/Fm), actual quantum yield of PSII (${\Phi}_{PSII}$), and photochemical quenching (qP) in rice, but increased non-photochemical quenching (NPQ). Decreases in Fv/Fm, ${\Phi}_{PSII}$, and qP were significantly alleviated by $30\;{\mu}M$ jasmonic acid (JA), while NPQ increase was enhanced. Transcription levels of antioxidant isoenzyme genes were differentially modulated by NaCl treatment. Expression of cCuZn-SOD2 gene increased, while those of cAPXb, CATb, and CATc genes decreased. JA prevented salt-induced decrease of pCuZn-SOD gene expression, but caused greater decrease in mRNA levels of cAPXa and Chl_tAPX genes. Investigation of vacuolar $Na^+/H^+$ exchanger (NHX2) and 1-pyrroline-5-carboxylate synthetase (P5CS) gene expressions revealed transcription level of NHX2 gene was increased by JA, regardless of NaCl presence, while that of P5CS gene slightly increased only in co-presence of JA and NaCl. Unlike JA, ${\gamma}$-radiation rarely affected expressions of antioxidant isoenzyme, NHX2, and P5CS genes, except for increase in mRNA level of Chl_tAPX and decrease in that of pCuZn-SOD. These results demonstrate enhanced salt-tolerance in JA-treated rice seedlings may be partly due to high transcription levels of pCuZn-SOD, NHX2, and P5CS genes under salt stress.

Biological Resources Potential and the Recent State of International Cooperation in Indonesia

  • Park, Chang-Ho;Junaedi, Ahmad;Lee, Mi-Ra;Lee, Yeon-Hee
    • Interdisciplinary Bio Central
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    • v.2 no.4
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    • pp.11.1-11.8
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    • 2010
  • Indonesia is a mega-biodiversity country having at least one trillion US Dollars value of biological resources per year over the next 20 years. Indonesia is home to 11 percent of the world's flowering plant species and 12 percent of all mammals. Many of Indonesia's species and more than half of the archipelago's endemic plant species are found nowhere else on the Earth. This information is just a small portion of all higher plants and animals being found in Indonesia. Former studies described that total number of species in Indonesia is estimated more than 1,000,000 and most of them remain unknown scientifically. Most of lower plants and animals have not been studied yet, so that greatest portion of Indonesia's biological resources has never been assessed with respect to its economic value or conservation status. Many developed countries are building cooperation with Indonesia on resources, mainly in the fields of grant aid, socio-economic services, R & D, researcher exchange, technology transfer, infrastructure, education/training, finance, etc. Indonesia will obtain greater benefits and management of its biological richness via increasing its international capacity to add value and information to its biological diversity. These goals can be achieved by close international collaboration on search of important biological resources and other bioactive products that have potential economic values. Development of biological resource-based technology stands as the industry of the $21^{st}$ century and, therefore, Indonesia has a unique opportunity to lead the process in the world.

Partial Characterization of Allelopathic Substances in Sorghum Stem by Different Organic Solvents and pH (수수 줄기에 함유(含有)된 타감물질(他感物質)의 용매(溶媒)와 pH에 따른 특성구명(特性究明))

  • Kim, S.Y.;De Datta, S.K.;Robles, R.P.;Kim, K.U.;Lee, S.C.;Shin, D.H.
    • Korean Journal of Weed Science
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    • v.14 no.1
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    • pp.42-48
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    • 1994
  • The toxic compounds of sorghum stem extracts were isolated by different organic solvents and pH, and characterized and quantified in terms of their inhibition of seed germination and seedling growth in Echinochloa colona(L.) Link and radish(Raphanus sativus L.). Sequential partitioning of stem extract with various organic solvents with increasing polarity showed that all fractions of hexane, ethyl ether, methylene chloride, ethyl acetate, and the aqueous remainder inhibited germination and seedling growth in E. colona. Of the five fractions, the ethyl ether fraction had the greatest inhibitory effect on E. colona. Further separation of the ethyl ether fraction at different pH(pH 2-11) showed that phytotoxic compounds were acidic. The result indicates that the phytotoxin present in the stem extract may be nonpolar and acidic.

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Protective Activity Against Oxidative Stress of Plants Indigenous to Korea

  • Jung Myung Sun;Kang Kyoung Ah;Zhang Rui;Chae Sungwook;Yoo Byoung-Sam;Yang Young Taek;Lee Nam Ho;Park Jae Woo;Hyun Jin Won
    • Toxicological Research
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    • v.21 no.4
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    • pp.279-284
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    • 2005
  • We have screened the cytoprotective effect against $H_2O_2$ and $\gamma-ray$ radiation induced oxidative stress from 32 Korean plants. Betula ermani var.saitoana (caulis, leaves), Rosa wichuraiana (caulis), Sorbus commixta (caulis), Weigela florida (leaves), Cirsium rhinoceros (whole plant), and Viburnum erosum (caulis) were found to scavenge 1, 1-diphenyl-2-picrylhydrazyl (DPPH) radical and intracellular reactive oxygen species (ROS). As a result, extracts of six plants reduced cell death of Chinese hamster lung fibroblast (V79-4) cells induced by $H_2O_2$ treatment. In addition, these extracts protected cell death of V79-4 cells damaged by $\gamma-ray$ radiation. In addition, these extracts scavenged ROS generated by radiation. Taken together, the results suggest that Betula ermani var. saitoana, Rosa wichuraiana, Sorbus commixta, Weigela florida, Cirsium rhinoceros, and Vibumum erosum protect V79-4 cells against oxidative damage by radiation through scavenging ROS.

Analysis of the content of essential oils from Ssajuari and Sajabalssuk according to storage period (강화산 애엽(艾葉)의 보관기간에 따른 정유성분의 변화)

  • Choi, Ho-Young;Ham, In-Hye;Choi, Cheol-Han;Bang, Chan-Sung;Lee, Byung-Hee;Cheng, Hae-Gon;Bu, Young-Min;Kim, Ho-Cheol
    • The Korea Journal of Herbology
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    • v.22 no.4
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    • pp.271-277
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    • 2007
  • Objective : The content of essential oils from Ssajuari and Sajabalssuk was analyzed based on storage period. A total of eight samples old Ssajuari (harvested in 2000, 2001, 2002, 2003, and 2004), fresh Ssajuari (harvested in 2004), old Sajabalssuk (harvested in 2002), and fresh Sajabalssuk (harvested in 2004) was analyzed. Methods : The analysis of the content of essential oils from Ssajuari and Sajabalssuk was conducted by GC/MS. Results : The main essential oils of Ssajuari were ${\beta}$-thujone and 1.8-cineole. The ${\alpha},{\beta}$-thujone and 1,8-cineole were increased but the caryophyllene oxide was decreased. in accordance with storage period. The main essential oils of fresh Sajabalssuk were trans-${\beta}$-caryophyllene, terpinen-4-ol. The main essential oils of old Sajabalssuk was ${\beta}$-thujone and 1,8-cineole like Ssajuari. But 1,8-cineole was higher than that of Ssajuari samlpes. Conclusion : All samples had trans-sabinene hydrate, 1,8-cineole, terpinen-4-ol and caryophyllene oxide. According to stored year, ${\beta}$-thujone, ${\alpha}$-thujone were increased but terpinen-4-ol, caryophyllene oxide were decreased.

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Protective Activity against Ionizing Radiation of Antioxidative Plants Indigenous to Korea

  • Jung, Myung-Sun;Kang, Kyoung-Ah;Zhang, Rui;Chae, Sung-Wook;Yoo, Byoung-Sam;Yang, Young-Taek;Lee, Nam-Ho;Park, Jae-Woo;Hyun, Jin-Won
    • Natural Product Sciences
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    • v.12 no.1
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    • pp.1-7
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    • 2006
  • We have screened the cytoprotective effect on ${\gamma}-ray$ radiation induced oxidative stress from forty one Korean plant extracts. Carpinus laxiflora (caulis), Quercus salicina (caulis), and Castanopsis cuspidata (caulis) were found to scavenge 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical and intracellular reactive oxygen species (ROS). As a result, extracts of three plants reduced cell death of Chinese hamster lung fibroblast (V79-4) cells induced by $H_2O_2$ treatment. In addition, these extracts protected cell death of V79-4 cells damaged by ${\gamma}-ray$ radiation. In addition, these extracts scavenged ROS generated by radiation. Taken together, the results suggest that Carpinus laxiflora, Quercus salicina, and Castanopsis cuspidata protect V79-4 cells against oxidative damage by radiation through scavenging ROS.

Development of an Electronic Nose System for Evaluation of Freshness of Pork (돈육의 신선도 평가를 위한 전자코 시스템 개발)

  • Lee, Hoon-Soo;Cho, Byoung-Kwan;Chung, Chang-Ho;Lee, Ki-Teak;Jo, Cheo-Run
    • Journal of Biosystems Engineering
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    • v.34 no.6
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    • pp.462-469
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    • 2009
  • The aim of this study was to develop a portable electronic nose system for freshness measurement of stored pork. An electronic nose system was constructed using seven different MOS sensor array. To determine the quality change of pork with storage time, the samples were divided into ten groups in terms of storage time with an increment of 2 day up to 19 storage days. GC-MS, total bacteria's count (TBC), thiobarbituric acid reactive substance (TBARS), and pH analyses as well as the analysis of the electronic nose system measurement were performed to monitor the freshness change of the samples. To investigate the performance of the electronic nose system for detecting the change of freshness of pork, the acquired signal values of the system were compared with those of GC-MS, TBC, TBARS, and pH analysis values. According to principal component analysis (PCA) and linear discriminant analysis (LDA) with the signals of the electronic nose system for the pork samples, the sample groups were clearly separated into two groups of 1-9 days and 11-19 days, and four groups of 1-3 days, 5-9 days, 11 days, and 13-19 days respectively. The results show that the electronic nose system has potential for evaluating freshness of pork.

Effects of Dietary Nitrogen Sources on Fiber Digestion and Ruminal Fluid Characteristics in Sheep Fed Wheat Straw

  • Tan, Z.-L.;Lu, D.-X.;Hu, M.;Niu, W.-Y.;Han, C.-Y.;Ren, X.-P.;Na, R.;Lin, S.-L.
    • Asian-Australasian Journal of Animal Sciences
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    • v.14 no.10
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    • pp.1374-1382
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    • 2001
  • Fifteen Inner Mongolian wethers with permanent ruminal and duodenal cannulas were used to study the effects of dietary rumen-undegradable protein (RUP) to rumen-degradable protein (RDP) ratios or protein sources on fiber digestion in the gastrointestinal tract and ruminal fluid characteristics. Fiber digestion and ruminal fermentation were not affected (p>0.05) by dietary RUP to RDP ratios (from 1.54 to 0.72). Soybean meal supplementation improved ruminal digestion. Fish meal supplementation increased (p<0.05) the ruminal degradability of fiber. The different RUP to RDP ratios (from 1.54 to 0.72) did not influence (p>0.05) ruminal fluid pH, but there were differences (p<0.05) in ruminal fluid $NH_3-N$ concentration because of urea replacement. Soybean meal as a dietary protein source decreased (p<0.05) ruminal fluid pH and increased (p<0.05 or p<0.01) $NH_3-N$, acetate, propionate and butyrate concentrations in the rumen. Fish meal as a dietary protein source decreased (p<0.05 or p<0.01) ruminal $NH_3-N$ and acetate concentrations and increased (p<0.05) ruminal propionate concentration. It can be concluded that dietary protein sources have more significant effect on fiber digestion and ruminal fermentation than different dietary RUP to RDP ratios, when the dietary crude protein requirements of growing sheep are satisfied.

Effects of Flavonoid-rich Plant Extracts on In vitro Ruminal Methanogenesis, Microbial Populations and Fermentation Characteristics

  • Kim, Eun T.;Guan, Le Luo;Lee, Shin J.;Lee, Sang M.;Lee, Sang S.;Lee, Il D.;Lee, Su K.;Lee, Sung S.
    • Asian-Australasian Journal of Animal Sciences
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    • v.28 no.4
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    • pp.530-537
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    • 2015
  • The objective of this study was to evaluate the in vitro effects of flavonoid-rich plant extracts (PE) on ruminal fermentation characteristics and methane emission by studying their effectiveness for methanogenesis in the rumen. A fistulated Holstein cow was used as a donor of rumen fluid. The PE (Punica granatum, Betula schmidtii, Ginkgo biloba, Camellia japonica, and Cudrania tricuspidata) known to have high concentrations of flavonoid were added to an in vitro fermentation incubated with rumen fluid. Total gas production and microbial growth with all PE was higher than that of the control at 24 h incubation, while the methane emission was significantly lower (p<0.05) than that of the control. The decrease in methane accumulation relative to the control was 47.6%, 39.6%, 46.7%, 47.9%, and 48.8% for Punica, Betula, Ginkgo, Camellia, and Cudrania treatments, respectively. Ciliate populations were reduced by more than 60% in flavonoid-rich PE treatments. The Fibrobacter succinogenes diversity in all added flavonoid-rich PE was shown to increase, while the Ruminoccocus albus and R. flavefaciens populations in all PE decreased as compared with the control. In particular, the F. succinogenes community with the addition of Birch extract increased to a greater extent than that of others. In conclusion, the results of this study showed that flavonoid-rich PE decreased ruminal methane emission without adversely affecting ruminal fermentation characteristics in vitro in 24 h incubation time, suggesting that the flavonoid-rich PE have potential possibility as bio-active regulator for ruminants.