• 한국초지조사료학회지
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• 제36권1호
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• pp.34-40
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• 2016

본 시험은 가공 조사료 이용확대를 위해 압축 방법과 수분 함량이 이탈리안 라이그라스 큐브의 물리적 및 화학적 성상에 미치는 영향을 구명하기 위하여 수행되었다. 이탈리안 라이그라스 큐브 제작을 위해 평판 다이형 큐브 기계를 직접 제작하였으며 이탈리안 라이그라스의 수분 함량을 15, 20, 25 및 35%로 조절하여 큐브를 제조하여 품질을 조사하였다. 수분 함량이 15~20%에서는 간헐적인 균열이 일어났으며 가루 발생량도 10~16%로 다른 처리보다 낮게 나타났다. 경도에 있어서도 15% 수분 함량에서 159 kg/f로 가장 높게 나타났으며 30% 수분 함량에서는 70 kg/f로 가장 낮았다. 그러나 전기 부하량과 큐브의 표면 온도는 수분 함량이 낮은 곳에서 더 높게 나타났다. 수분 함량에 따른 큐브의 일반 조성분은 조제전에 비하여 조단백질과 조지방 함량은 높아졌으며 조섬유, ADF, NDF 함량은 감소하는 것으로 나타났다. 조회분 함량은 수분 함량 30%를 제외하고는 큐브 조제 전후간에 차이를 보이지는 않았다. 수분 함량에 있어서는 수분이 많아질수록 조단백질 함량이 증가되는 경향을 보였으며 조섬유, 조회분 함량은 처리간에 차이가 나타나지 않았다. NDF 및 ADF 함량은 30% 수분 함량에서 가장 낮게 나타났다. 이상의 결과를 종합하여 볼 때 이탈리안 라이그라스 큐브 조제를 위한 적정 수분함량은 15~20% 내외로 추정되며 이로 인해 사료적 가치가 향상되는 것으로 나타났다.

• Composites Research
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• 제24권4호
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• pp.48-54
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• 2011

본 연구에서는 탄소/에폭시 복합재 단일겹침 접착체결부의 염수 수분율이 체결부의 강도 및 파손모드에 미치는 영향을 연구하였다. 시편은 이차접착 방식으로 제작하였고, $71^{\circ}C$, 3.5% 염수환경에서 수분율 0, 0.2, 0.5, 1.0, 2.0%(포화상태)를 갖도록 노출시켰다. 수분율별 시편은 각 8개씩이고, 두 종류의 시험환경을 고려하여 총 80개의 시편에 대한 시험을 수행하였다. 시험결과 복합재 체결부의 강도는 수분율이 2%(포화상태)에 도달하면 감소하지만 그 이전 과도상태(약 1% 근처까지)에서는 오히려 증가하는 것으로 나타났다. 또한 수분율 1%까지는 고온 환경에서의 강도가 상온 강도보다 2~5% 가량 높게 나타났다. 그러나 수분 포화된 고온 환경 체결부의 강도는 상온 강도 대비 약 5% 가량 저하되는 것으로 나타났다.

• 한국농공학회논문집
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• 제58권5호
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• pp.81-90
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• 2016

Due to droughts and water shortages causing severe damage to crops and other vegetations, much attention has been given to efficient irrigation for upland farming. However, little information has been known to measure soil moisture levels in a field scale and apply their spatial variability for proper irrigation scheduling. This study aimed to characterize the spatial variability and temporal stability of soil water contents at depths of 10 cm, 20 cm and 30 cm on flat (loamy soil) and hill-slope fields (silt-loamy soil). Field monitoring of soil moisture contents was used for variogram analysis using GS+ software. Kriging produced from the structural parameters of variogram was applied for the means of spatial prediction. The overall results showed that the surface soil moisture presented a strong spatial dependence at the sampling time and space in the field scale. The coefficient variation (CV) of soil moisture was within 7.0~31.3 % in a flat field and 8.3~39.4 % in a hill-slope field, which was noticeable in the dry season rather than the rainy season. The drought assessment analysis showed that only one day (Dec. 21st) was determined as dry (20.4 % and 24.5 % for flat and hill-slope fields, respectively). In contrary to a hill-slope field where the full irrigation was necessary, the centralized irrigation scheme was appeared to be more effective for a flat field based on the spatial variability of soil moisture contents. The findings of this study clearly showed that the geostatistical analysis of soil moisture contents greatly contributes to proper irrigation scheduling for water-efficient irrigation with maximal crop productivity and environmental benefits.

• 한국작물학회지
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• 제49권4호
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• pp.295-299
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• 2004

The prices of domestic green tea products are relatively expensive and price differences within products of the same levels of quality are various. Also, there is no basic criteria on evaluation of green tea quality. To group 43 commercial green tea products into several parts by the principal component and cluster analyses, this work was done by use of 8 chemical constituents which were analyzed by NIR system. The principal component and cluster analyses revealed 8 groups. The first group included 16 products that had lower free amino acid and theanine contents. The second group included 5 products having higher free amino acid and theanine contents, but lower ash contents. The third group included 13 products showing medium values of 8 constituents. The IV group included 4 products having higher contents of moisture, free amino acids, and theanine. The V group included 1 product showing higher moisture but lower catechins contents. The VI group included 2 products that had higher moisture and catechins contents, but lower free amino acid and theanine contents. The VII group had higher moisture and catechins contents. The VIII group had higher ash and vitamin C contents. The free amino acid contents which were the most important in flavor evaluation of green tea quality did highly positively correlate with the contents of total nitrogen $(0.956^{**}),\;theanine\;(0.981^{**}),\;and\;caffeine\;(0.793^{**})$, but negatively with the contents of ash $(-0.884^{**})$. The catechins used as for functional ingredients did correlate with contents of caffeine(+) and vitamin C(-), respectively.

• 한국세라믹학회지
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• 제45권12호
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• pp.832-838
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• 2008

Diatomite, bentonite and zeolite were used as porous materials for fabricating hygroscopic panels. Moisture adsorption and desorption of porous materials were investigated and hydrothermal method was applied to fabricate panels. Cheolwon diatomite and Pohang zeolite showed excellent characteristics of moisture adsorption and desorption. These characteristics were caused by higher surface area and pore volume of porous materials. Correlation coefficient between surface area and moisture adsorption content of porous materials was 0.93. Moisture adsorption contents were influenced by surface area and pore volume of panels, and surface area more effected on moisture adsorption. Correlation coefficient between surface area and moisture adsorption content of panels was 0.86. Moisture adsorption content of panel with 10% Pohang zeolite was $180\;g/m^2$ and that of 10% Cheolwon diatomite was $170\;g/m^2$. Moisture desorption content of panel with 10% Pohang zeolite was $105\;g/m^2$. Moisture adsorption contents of panel with porous materials were higher than that of panel without porous materials.

• 한국식품과학회지
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• 제29권5호
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• pp.932-938
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• 1997

Changes in viscosity and dynamic theological properties of Job's-tears were measured by Bohlin dynamic tester as a function of moisture, and measurement was performed within a linear viscoelastic range. The result of the shear stress vs shear rate of Job's-tears at different moisture contents $(50{\sim}75%)$ was applied to mathematical models and Herschel-Bulkley model showed the highest correlation coefficient. Lower moisture content (55%) produced higher yield stress and consistency index, but lower flow behavior index, whereas higher moisture content showed reverse effects. Job's-tears with $50{\sim}70%$ moisture contents showed a higher storage modulus (G') than loss modulus (G') at all frequencies, showing a higher concentrated polymer characteristics. However, higher moisture content (>75%) showed crossover point between G' and G', and frequency dependency. As the moisture content was increased, the amount of viscoelastic properties such as G', G', complex viscosity decreased during heating, and initial temperature and miximum value of viscoelastic properties shifted to higher temperatures, representing the moisture-dependence of Job's-tears upon theological properties.

• Journal of Biosystems Engineering
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• 제27권2호
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• pp.125-132
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• 2002

In order to investigate the optimum moisture content of paddy for milling process, a series of tests were conducted by examining the recovery rate and whiteness of milled rice in relation with the various moisture content. Hwabong-byeo and Dongjin-byeo varieties which were major paddies cultivated in Korea were used for the experiment. The test was performed with small experimental milling machines. In order to minimize the unexpected factors, environment conditions were kept in constant during the experiment. As a result, the recovery rate of milled rice were varied as the changes in milling time and degree of whiteness. However, the recovery rate of milled rice increases as its moisture content increases untill a certain point of moisture content and decreases slowly afterward. This certain point can be called optimum moisture content for rice milling. Also, it has a different value depending on the variety. In this experiment, optimum moisture content of Hwabong-byeo and Dongjin-byeo were considered around 14.8% and 15.3%, respectively. It is not sure that these optimum moisture contents for the two varieties would assume the same values irrespective of harvest year and place. However, it could be concluded that the optimum moisture content for rice milling is around 15%(w.b.) for Hwabong-byeo and 15.5%(w.b.) for Dongjin-byeo, respectively.

• 한국작물학회지
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• 제43권2호
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• pp.101-104
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• 1998

This study was conducted to establish a rapid analysis method for determining protein and moisture contents of pea. Ninety and eighty pea (Pisum sativum L.) lines were analyzed to determine protein and moisture contents, respectively using near-infrared reflectance spectroscopy. Simple correlations (${\gamma}$) of protein content in a ground sample and an intact grain sample by an automatic regression method were 0.978 and 0.910, respectively. Simple correlations by partial least square regression/principal component analysis (PLS/PCA) methods were 0.982 and 0.925, respectively. Standard error of performance (SEP) in protein content was the lowest value, 0.446 in ground sample by PLS/PCA methods. Simple correlation of moisture content was the highest at 0.871 in ground samples. when using a standard regression method. Accuracy for the moisture content was slightly lower than for protein content. It was concluded that the NIRS method would be applicable only for rapid determination of protein content in pea.

• 한국안전학회지
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• 제12권1호
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• pp.71-76
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• 1997

In this paper, it was described results of study on curing safety of molding meterial, about the variation of phenol resin contents, wood flour contents and moisture of wood flour, under the same condition. The experimental results are summarized as follows ; 1) When the curing temperature was high, the curing time was short in the case of 4～8wt% moisture of wood flour, but in the case of more than l2wt% moisture of wood flour, the curing time was long. 2) The curing time for curing temperature was more short when 6wt% moisture of wood flour than 4wt% moisture of wood flour. 3) The more wood flour content and moisture of wood flour content, the longer curing time and the more mineral filler content, the shorter curing time. 4) When the phenol resin content of main matrix increase, the curing time was short.

• 한국자원식물학회지
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• 제23권2호
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• pp.172-178
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• 2010

천연집단에 서식하는 개비자나무 개체들을 이용해 무생물 및 생물적 환경인자가homoharringtonine(HHT) 함량에 미치는 영향을 조사하여 향후 항암제 가능성이 있는 HHT의 고부가가치 산업적인 생산이 기대되는 연구에 기초자료를 제공하고자 본 연구를 수행하였다. 무생물적 환경인자(토양습도, 토양pH, 서식밀도, 기온)와 HHT 함량과의 상관관계에 있어 HHT 는 토양습도(0.77)와 토양pH(-0.68)에서 높은 상관을 보였다. 고도에 따른 무생물적 환경인자 (토양습도, 토양pH)와 HHT 의 함량 관계에 관해 다중회귀 분석을 실시한 결과, 토양 습도의 회귀계수($26.48^{***}$) 만 유의하여 토양 습도가 상대적으로 HHT 함량에 높은 영향을 미치는 것으로 나타났다. 생물적 환경인자(damage index)에 따른 HHT 함량에 미치는 영향을 살펴 본 결과, HHT는 2차곡선회귀적으로 증가하다 감소하는($H=278.23+1242D-398.87D^2$) 경향을 보였고 damage index는 HHT 함량에 높은 영향을 미치는 것으로 분석되었다. 마지막으로 HHT 의 함량에 영향을 미치는 최적환경인자를 분석한 결과, damage index와 토양 습도 모두가 2차다항회귀식으로 가장 적합하였고 결정계수는 각각 0.73와 0.67로 damage index가 상대적으로 HHT 함량에 높은 영향을 미치는 것으로 나타났다. 이는 섭식자 또는 균류와 같은 스트레스로 인한 방어기작이 HHT 의 생성에 높은 영향을 미치는 것으로 판단된다.