• Journal of Practical Agriculture & Fisheries Research
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• v.21 no.2
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• pp.35-47
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• 2019

The mycelial growth of P. coccineus strain was good in PDA and YMA, but mycelial growth was low in MEA. Light irradiation during the incubation period affected the pigment formation and density of mycelia. Mushroom of P. coccineus strain was able to produce fruiting bodies in both bottle and bag cultivation, and oak sawdust was found to be the most suitable substrate for spawn culture and cultivation. In artificial cultivation using sawdust medium, fruiting body was grown to the extent that visual observation was possible from the 15th day, and it formed about 5 days fast in the treatment group with low relative humidity. From 40 to 45 days of mushroom development, mature fruiting bodies could be harvested, and the lower relative humidity of the growing room favored mushroom development and growth. Antioxidant activity of fruiting bodies harvested from artificial cultivation showed that ABTS radical scavenging activity of bottle-cultivated and wild fruit bodies were shown at 505㎍/㎖ and 515㎍/㎖, respectively. However, fruiting bodies harvested in bag cultivation were high at 910㎍/㎖. As a result of DPPH radical scavenging activity, all extracts were found to be inactive, exhibiting IC₅₀ value of more than 2,000㎍/㎖ concentration. The ethyl acetate extract of mushrooms obtained from bottle cultivation showed the highest activity with 1,550㎍/㎖ IC₅₀ value. Methanol extract of wild fruit bodies had the highest ABTS radical scavenging activity at the same concentration (10mg/㎖).

• Weed & Turfgrass Science
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• v.7 no.3
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• pp.231-238
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• 2018

This study was carried out to develope new zoysiagrass cultivars 'JangsungChorok' (Application No. :2013-3) and 'JangsungSaetbyeol' (Application No. :2013-4). One hundred and one genetic resources were collected at Jangsung Gun area from 2010 to 2011. Among the collected lines, CY6097 (JangsungChorok) and CY6069 (JangsungSaetbyeol) showed superior performance in spring green up and growth rate. 'JangsungChorok' showed genetically light green leaf color, with medium leaf width (4.4 mm), height from ground to first leaf blade of 3.2 cm and average plant height of 18 cm. Fast recovery rate and early spring green up rate will make this cultivar (JangsungChorok) for efficient sod producer. 'JangsungSaetbyeol' showed genetically dark green leaf color, with fine to medium leaf width of 3.5 mm, height from ground to first leaf blade of 4.3 cm and average plant height of 22.6 cm. Fast recovery rate and early spring green up rate with relatively narrow leaf will make this cultivar (JangsungSaetbyeol) for high sod quality.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.8 no.2
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• pp.151-158
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• 2010

In order to measure the deposition velocity of $I_2$ vapor for radish plants and its translocation factor for their roots, radish plants were exposed to $I_2$ vapor for 80 min. at different growth stages between 29 and 53 d after sowing. The exposure was performed in a transparent chamber during the morning time. Deposition velocities ($ms^{-1}$) were on the whole in the range of $1.0{\times}10^{-4}{\sim}2.0{\times}10^{-4}$ showing an increasing tendency with an increase in the biomass density. The results showed some agreement with existing reports that a higher relative humidity would lead to a higher deposition velocity. The acquired deposition velocities were lower than by factors of several tens than some field measurements probably due to a very low wind speed (about $0.2\;ms^{-1}$) in the chamber. Translocation factors (ratio of the total iodine in the roots at harvest to the total plant deposition), estimated in a more or less conservative way, were $1.3{\times}10^{-3}$ for an exposure at 29 d after sowing and $5.0{\times}10^{-3}$ for an exposure at 53 d after sowing. In using the present experimental data, meteorological conditions and chemical and physical forms of iodine need to be carefully considered.

• Korean Journal of Environmental Agriculture
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• v.38 no.3
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• pp.166-172
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• 2019

BACKGROUND: Increase in the ratio of small berries in blueberry production decreases the farmers' profits due to weakening market competitiveness and lowering harvest efficiency. One of the reasons for increased small berries is over fruit-load. For improving productivity and competitiveness of blueberry in Korea, hand-thinning can be applied to increase fruit quality before the developing adequate chemical thinning methods. This study was conducted to investigate the proper timing and methods for floral buds thinning in rabbiteye blueberry. METHODS AND RESULTS: Eight years old bushes of rabbiteye bluberries 'Brightwell' as a primary cultivar and 'Powderblue' as a pollinizer were used for this study. Fruit size distribution by leaf-to-fruit ratio was investigated by counting the number of leaves and fruits in canes of 127 'Brightwell' plants whose fruit set varied. Fifty percent of flowers/floral buds were removed in four different floral buds stages such as bud swell, late pink bud, full bloom, and petal fall, and the consumed time for thinning and fruit characteristics were recorded to investigate the effect and proper timing of floral buds thinning. Fruit weight and soluble solids content tended to increase in proportion to leaf-to-fruit ratio and the production of the number of fruits less than 13 mm in diameter decreased when leaf-to-fruit ratio was more than 2.5. Manual floral buds thinning by hands was fastest in full bloom stage and slowest in bud swelling stage. In all cultivars, fruit size was significantly smaller in non-thinning treatment than thinning, and there was, however, no significant difference in total fruit yield. The number of fruits less than 13 mm in diameter increased in both cultivars as floral buds thinning was delayed. Consumed time for picking 90% berries out of total berries per bush was shortest in full bloom stage thinning in 'Brightwell' and bud swelling, full bloom thinning in 'Powderblue'. These were 25 and 20 days faster than no thinning, respectively. CONCLUSION: Although the effect of floral buds thinning varied depending on the cultivars, our results confirmed that floral buds thinning was effective for the early intensive harvesting and the increase of the large fruit ratio and the harvesting productivity. Also, in order to increase thinning efficiency, it is recommended to remove the flower buds before the full bloom stage.

• Elastomers and Composites
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• v.34 no.3
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• pp.253-261
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• 1999

The cure properties of rubber compounds containing different adhesive compositions were examined. As the amounts of tannin were increased in the adhesive composition, the scorch time was increased and cure rate was decreased due to the size and shape of tannin molecules. Also, the effect of adhesive composition on the adhesion between rubber and fiber was examined by TCAT(Tire Cord Adhesion Test), The reinforcing cords used in this study were mon ofilaments of nylon 610 and nylon 66. According to the results, the optimum adhesion strength between rubber and fiber could be obtained with adhesives whose molar ratios of formaldehyde/resorcinol were above 5/1 in the recipes. Although the level of dip pick-up(DPU) on the reinforcing cord affects the adhesion strength, the DPU of nylon 610 monofilament did not affect the adhesion strength because the level of DPU was constant regardless of the adhesive compositions. In this case, the adhesion strength with the adhesive composition could be explained with the behavior of tannin in the adhesive.

• Korean Journal of Food Science and Technology
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• v.16 no.3
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• pp.297-302
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• 1984

Kinetics of water diffusion during soaking of two brown rice varieties, Akibare (traditional rice) and Milyang 23 (high-yielding rice), were studied. Brown rice reached at the equilibrium moisture content after 18 hours. The absorption of liquid water by brown rice grain was directly proportional to the square root of hydration time and could be described by the simplified solution of Fick's diffusion equation. The diffusion coefficient was given by the Arrhenius relation: $D\;=\;2.738{\time}10^{-1}\;exp\;(-9,300/RT)$ for Akibare and $D\;=\;4.302{\time}10^{-1}\;exp\;(-9,500/RT)$ for Milyang 23. Hydration rate calculated from hardness change followed the equation of a first order reaction. Hydration mechanism of brown rice was changed at the gelatinization temperature of rice starch.

• Korean Journal of Breeding Science
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• v.41 no.4
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• pp.525-528
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• 2009

A new rose cultivar was developed from a cross between "Neon" and "Hello" by the rose breeding team of Gyeonggi-Do Agricultural Research and Extension Services in 1999. The cultivar, "Loving You" was finally selected in 2007 after evaluation trials for three years (2005-2007). The cultivar was developed for a standard-type cut flower with pink petals. "Loving You" grows vigorously and produces $108.5stems/m^2$ in a year, and has 50.2 petals per flower. The days to flower was 46 days, which is very short in rose. The length of cut flower was long with 76.8 cm. Vase-life of the cultivar could be as long as 11 days. The cultivar was applied for a variety protection in 2007.

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 2017.04a
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• pp.65-65
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• 2017

밭작물 중 양파와 마늘은 높은 노동투하시간, 노임의 상승, 복잡한 수거 과정 등으로 최근 재배면적이 감소하는 추세이다. 밭농업 활성화 방안으로 생산비 절감과 작업 속도 향상을 위한 수확기계 개발 연구로 줄기절단기가 개발되었다. 이 연구는 줄기절단기 예취날의 설치각이 절단부하에 미치는 영향을 분립체 해석 기법으로 분석하고자 하였다. 실험에 사용한 시뮬레이션은 EDEM으로 인장탄성계수, 전단탄성 계수, 중첩길이, 입자 반경 및 질량, 상대속도를 이용하여 충돌시 힘을 해석하고 인장 및 전단강도, 한계, 결합 길이를 통해 입자간 결합을 설정할 수 있다. 시제품으로 설계된 줄기절단기의 치수를 활용하여 프로그램 상에서 줄기 절단 시뮬레이션을 진행하여 절단부하 결과를 얻도록 하였고 칼날 설치각을 30도, 45도, 60도로 변경하여 각각의 부하를 분석하여 경향성을 파악하고자 하였다. 실험에서 사용한 프로그램은 EDEM 2.7.1 Academic Research 버전이며 시뮬레이션을 진행한 PC의 사양은 Intel(R) $Core^{TM}$ i7-4790 CPU @ 3.60GHz, Memory 16.0GB이다. 줄기 절단 시뮬레이션에 적용시킨 줄기 모델은 마늘의 조건을 적용시켜 직경 1mm의 입자로 이루어진 지름 12mm, 높이 214mm의 원통형 모델이며 60.32N의 최대절단력을 가지고 있다. 줄기절단기는 2개의 회전날을 가지고 있으나 좌우대칭을 적용하여 절반에 대한 해석으로 하나의 회전날로 절단을 하도록 줄기 모델은 4조로 하여 3열을 140mm 간격으로 위치시켰다. 줄기절단기의 칼날은 반경 350mm로 회전하며 진행속도는 1.65m/s, 회전속도는 1680rpm으로 작업하도록 하였다. 시뮬레이션은 0.5초의 시간에 대해 해석하도록 하였으며 0.003초 간격으로 칼날에 가해지는 힘을 구하여 저장하도록 하였다. 시뮬레이션 해석시간은 약 116시간이었으며 설치각별 시간에 따른 칼날에 가해지는 압축력 값과 그래프를 얻을 수 있었다. 대부분의 시간에서 절단이 이루어지지 않으므로 0의 값을 나타내었으며 절단이 이루어지는 시점에 절단부하가 나타났다. 결과 해석을 위해 그래프의 피크 값들을 이용하였으며 그 중 상위 6개의 값으로 분석하였다. 30도, 45도, 60도의 설치각에 따른 절단부하의 평균 값은 각각 105.4N, 160.5N, 215.9N으로 나타났다. 설치각에 따른 절단부하의 경향성은 유의수준은 3.93%로 각각의 차이가 유의미하게 나타났으며 상관계수는 0.489로 증가하는 경향이 보였다. 그러나 $R^2$는 0.2394로 낮은 값을 보여 데이터 처리 방법의 개선과 적절한 회귀 모델의 적용이 필요하다. 향후 포장시험을 진행하고 복합적으로 분석하여 경향성을 자세히 분석하고자 한다.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.40 no.2
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• pp.236-244
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• 1995

This study was carried out to clarify the changes in dry matter weight and physicochemical property of job's tears grain during ripening period. Four varieties of job's tears were seeded at April 20, May 10, and May 30, andgrains were harvested at every 7 days from heading to maturity, The whole seed weight of thick hull varieties, Kimje and Aewon, was higher than that of improved thin hull varieties, Suwon 3 and Suwon 6, from heading to maturity, However, the dehulled grain weight of thin hull variety were higher than that of thick hullvariety from 35 days after heading. The first heading spikelet showed lower 100-grain weight com-pared with the spikelets headed at full blooming stage among the same plant. The increased rate of de hulled grain weight during maturing period was higher in thin hull variety than thick hull one, later seeding date than early seeding, and intermediate headed spikelet than early head-ed one, respectively. As maturing proceeds the protein content of de hulled grain was decreased, alkali digestibility value(ADV) showed a rising trend, and little change was found in gel consistency of milled grain flour. And same trends were found in protein content, ADV and gel consistency as the seeding date was delayed. Among amylogram properties of job's tears flour the maximum, minimum, and final viscosity as well as breakdown were decreased, and set back was increased in later seeding plots

• Journal of Bio-Environment Control
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• v.29 no.1
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• pp.28-35
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• 2020

This study is to compare irrigation efficiency between sap flow sensor automated system (SF) and conventional irrigation system based on integrated solar radiation automated system (ISR) in tomato rockwool hydroponics. Total irrigated volumes was higher in the ISR system by 5.0L per plant, a lower drainage rate was found in the SF system, compared to the ISR system. There was no difference in shoot and fruit fresh weights, water use efficiency (WUE) and water amount consumed for producing 200g of tomato fruit. The daily average sap flow density (SFD) was closer to the change of solar irradiance (SI) in the plant grown under the SF system, compared to the ISR system. The correlation coefficient (r²) between the fruit diameter and the volumetric water content during the 56 and 82 days after transplant showed the SF treatment was higher than the ISR at night and daytime, and the correlation was higher at night time. The sap flow density and humidity deficit (HD) of SF treatment was related as closely as the solar irradiance. Further studies should demonstrate that SF irrigation system is a convenient method for hydroponic farmers with advantages, such as growth, higher yield, WUE, and accuracy.