• Journal of the Korean Wood Science and Technology
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• 제19권2호
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• pp.30-39
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• 1991

Internal moisture gradients of 3cm-thick radiata pine (Pinus radiata) sapwood and meranti(Shorea spp.) heartwood were determined by using slicing method during drying and were predicted by Hart's Sorption Simulation. The shapes of internal moisture gradients. moisture contents and drying rates, which were obtained by the slicing method. were compared with those predicted by Sorption Simulation. After the 2nd fitting attempts. the differences between the gravimetric drying rates and the drying rates predicted by Sorption Simulation were less than 0.021%/hr for radiata pine and 0.043%/hr for meranti. The shapes of the internal moisture gradients predicted by Sorption Simulation were in good agreement with those obtained by the slicing method. It could be concluded that Sorption Simulation be an excellent tool to predict internal moisture gradients of wood.

• Food Science and Biotechnology
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• 제15권6호
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• pp.856-859
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• 2006

The effects of moisture content on non-fracture dynamic properties and fracture gel quality of Pacific whiting surimi were investigated to determine their relationships. Surimi samples were tested at various moisture contents (75, 78, and 81 %). Torsion test showed that shear stress decreased rapidly and strain values decreased gradually as moisture concentration increased. Dynamic storage modulus (G') also decreased as moisture content increased. A strong positive correlation ($R^2=0.90$ to 0.99) was found between the G' measured at temperatures between 10 and $45^{\circ}C$ and fracture stress values. The results indicate that dynamic rheological measurements could be used as a tool for early gel quality assessment.

• Structural Engineering and Mechanics
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• 제62권4호
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• pp.487-496
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• 2017

The focus of this study were to investigate patterns between wall pressures and stresses with grain moisture of soybean and rice varieties widespread cultivated in Turkey in order to determine needed designing parameters for structure analysis in silos at filling and discharge. In this study, the wall pressures and stresses were evaluated as a function of moisture contents in the range of 8-14% and 10-14% d.b. The pressures and von Mises stresses affected as significant by the change of grain moisture content. The main cause of pressure and stress drops is changed in bulk density. Therefore is extremely important bulk density and moisture content of the product at the structural design of the silos. 4 mm wall thickness, were determined to be safe for von Mises stresses in both soybean and rice silos is smaller than 188000 kPa.

• 한국식품과학회지
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• 제29권1호
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• pp.72-76
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• 1997

압출성형기의 모터에너지는 자가발열 열에너지와 기계에너지로 전환되며 히터에너지는 열에너지로 공급되는데 각 에너지가 녹말의 호화에 미치는 영향을 분석하였다. 저온$({\leq}80^{\circ}C)$ 압출성형조건에서 자가발열 에너지는 낮은 수분함량의 분체 마찰에 의한 것과 높은 수분함량의 점성에 의한 것으로 구분할 수 있었으며 분체 마찰에 의한 열에너지가 호화에 더 효과적임을 알 수 있었다. 또한 모터에너지에서 자가발열되고 남은 순수한 기계에너지의 효과를 상대기계에너지로 평가한 결과, 높은 수분함량$({\geq}33%)$ 조건의 호화는 상대기계에너지의 변화에 크게 의존하며 낮은 수분함량$({\leq}30%)$의 경우는 거의 영향을 받지 않는 것으로 나타났다.

• Journal of the Korean Wood Science and Technology
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• 제26권4호
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• pp.43-49
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• 1998

The availability of large quantities of waste woods provides an impetus for investigating woody biomass potential uses. Polyurethane (PU) foams are prepared with reacting isocyanates and polyols, and are used. in various industry fields. Thus, lignocellulosic waste raw-materials are proposed as replacement for synthetic polyol to PU foam formulation. In this study PU foams were manufactured from liquefied woods, methanediisocyanate(MDI), catalyst, foaming stabilizer, and viscosity aids. The polyol content, isocyanate.hydroxyl group (NCO/OH) ratio, and water content were varied to evaluate their effects on the foaming and water absorption of the PU foams. Less than 400 Molecular weight. of polyethylene glycol(PEG) and 1 to 3 solvent to woody raw-material ratio were desirable for liquefying woody materials. Liquefying rate was increased with more than 3 % addition of inorganic and organic catalysts and raising reaction temperature more than $150^{\circ}C$. Addition of starch enhanced liquefying of woody materials. Fourty percents of starch resulted in about 90% liquefying rates. Foaming rates were increased with increasing moisture contents of liquefied wood. Moisture contents of 0.6% resulted in 5 time-foaming rates, and seven percents of moisture contents more than 30 time-foaming rates. But, an increase in water content may result in a decrease in cross-links between wood polyol and isocyanate, because the NCO/OH ratio is constant. Increasing moisture contents have significantly decreased density of PU foams. The optimum water content should be about 2.5% or less in this adopted condition.

• 미생물학회지
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• 제17권1호
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• pp.16-24
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• 1979

In order to investigate the production of aflatoxin in various conditions such as pH, moisture and temperature, 27 smaples were inoculated with Aspergillus flavus, and in addition 3 smaples were inoculated with the mixture of Aspergillus flavus and Bacillus subtilis and cultured under the conditions such as $20^{\circ}C$ and 30% moisture contents. The following results were obtained : 1) Aflatoxin production was the highest at pH 5.0 and relatively high at pH 7.0. Its production was decreased significantly when pH reached 9.0. 2) The yield of aflatoxin was shown comparatively high level at 30% moisture contens. The higher moisture contents was, the lower aflatoxin production was. 3) The highest level of aflatoxin production was at $20^{\circ}C$, and comparatively high level was at $30^{\circ}C$. However, its production was fairly low at $40^{\circ}C$. 4) The highest crude aflatoxin production was 5,093ppm $(B_1,\;1.912\;ppm;\;B_2,\;0.521\;ppm;\;G_1,\;2.119\;ppm;\;G_2,\;0.541\;ppm)$ at 30% moisture, pH 5.0 and $20^{\circ}C$ and the lowest one 2.197 ppm $(B_1,\;0.793\;ppm;\;B_2,\;0.185\;ppm;\;G_1,\;0.102\;ppm;\;G_2,\;0.381\;ppm)$ at 63% moisture, pH 9.0 and $40^{\circ}C$ 5) When Aspergillus flavus and Bacillus subilis were cultured together under the conditions such as $20^{\circ}C$ and 30% moisture, aflatoxin production was decreased by 27% comparing with the culture of Aspergillus flavus alone.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2008년도 추계 학술발표회 제20권2호
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• pp.705-708
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• 2008

본 연구에서는 규조토, 벤토나이트, 제올라이트를 사용하여 건축내장용 조습패널을 제조하였으며,패널 제조에 사용된 원료의 특성에 따른 조습 성능 등을 평가해 보고자 하였다. 철원 규조토는 형태와 구조가 와해 변질된 상태로 존재하였으며, 포항 벤토나이트는 입자 표면이만곡 현상(彎曲 現狀)과 많은 기공을 관찰할 수 있었다. 제올라이트는 타원형 또는 구형의 형태를 가지고 있으며, 다수의 판상 입자들이 한개의 거대 입자(15$\mu$m 전후)를 형성하는 특징이 있었다. 또한 대부분의 원료들은 판상이거나 침상으로 다공질의 미세구조를 관찰할 수 있었다. 각 원료를 사용해 제조한 조습패널은 다공성 원료의 첨가로 인해 다공성 원료를 혼합하지 않은 패널 보다 수분의 흡방습 특성은 크게 개선되어, 포항 제올라이트 10% 패널의 경우에는 흡습량 180g/m$^2$, 방습량 105g/m$^2$ 수준이었다. 또한 패널의 비표면적 및 기공 부피와 수분 흡방습량과의 높은 상관성이 있음을 확인하였다. 또한 다공성 원료의 종류에 따라서도 패널의 수분 흡방습량은 차이가 있었으며, 이는 다공성 원료의 영향으로 판단되었다. 이때 철원 규조토를 10% 첨가한 패널의 수분 흡습량은 170g/m$^2$ 정도 였으며, 포항 제올라이트를 10% 첨가한 패널의 수분 흡습량은 180g/m$^2$, 방습량은 105g/m$^2$ 로 다공성 원료를 혼합하지 않은 패널(흡/방습량:80/40g/m$^2$) 보다 매우 우수한 흡방습능을 나타내었다.

• Asian-Australasian Journal of Animal Sciences
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• 제25권4호
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• pp.471-478
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• 2012

The role of moisture absorptive capacity of pre-silage material and its relationship with silage effluent in high moisture by-product feedstuffs (HMBF) is assessed. The term water retention capacity which is sometimes used in explaining the rate of effluent control in ensilage may be inadequate, since it accounts exclusively for the capacity of an absorbent incorporated into a pre-silage material prior to ensiling, without consideration to how much the pre-silage material can release. A new terminology, 'potential water retention capacity' (PWRC), which attempts to address this shortcoming, is proposed. Data were pooled from a series of experiments conducted separately over a period of five years using laboratory silos with four categories of agro by-products (n = 27) with differing moisture contents (highest 96.9%, lowest 78.1% in fresh matter, respectively), and their silages (n = 81). These were from a vegetable source (Daikon, Raphanus sativus), a root tuber source (potato pulp), a fruit source (apple pomace) and a cereal source (brewer's grain), respectively. The pre-silage materials were adjusted with dry in-silo absorbents consisting wheat straw, wheat or rice bran, beet pulp and bean stalks. The pooled mean for the moisture contents of all pre-silage materials was 78.3% (${\pm}10.3$). Silage effluent decreased (p<0.01), with increase in PWRC of pre-silage material. The theoretical moisture content and PWRC of pre-silage material necessary to stem effluent flow completely in HMBF silage was 69.1% and 82.9 g/100 g in fresh matter, respectively. The high correlation (r = 0.76) between PWRC of ensiled material and silage effluent indicated that the latter is an important factor in silage-effluent relationship.

• 한국식품저장유통학회지
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• 제11권2호
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• pp.257-262
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• 2004

본 연구는 벼의 함수율 및 온도별 안전저장기간을 구명하기 위하여 수행되었다. 벼의 함수율은 16.1∼22.2%범위에서 4수준, 온도는 10∼3$0^{\circ}C$에서 3수준으로 저장하면서 외관, 발아율, 지방산가를 측정하였고, 안전저장기간의 온도 및 함수율 의존성을 분석하였다. 그 결과를 요약하면 다음과 같다. 벼의 발아율은 저장온도가 증가할수록, 함수율이 높을수록 급격하게 저하한 반면, 지방산가는 저장기간에 따라 증가하였으나 온도보다는 함수율에 의한 영향이 크게 나타났다. 벼의 온도 및 함수율이 높을수록 변색립 및 곰팡이는 빨리 발현되었으며, 함수율 16.1%에서는 온도가 높아도 저장기간 내에 부패현상은 나타나지 않았다. 발아율, 지방산가 및 외관에 의한 저장가능기간 중 최소가 되는 저장기간으로 온도 및 함수율에 따른 안전저장기간을 제시하였다.

• Journal of Biosystems Engineering
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• 제34권2호
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• pp.114-119
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• 2009

Field test was conducted to investigate primary factors reducing rapeseed harvesting using a reciprocating cutter-bar of combine. The results showed that the correlation between crop moisture content and yield loss had a U-type, which indicated that the yield reduction increased at too high and too low crop moisture contents. The proper ranges of crop moisture contents were 27${\sim}$35%, 21${\sim}$56%, and 62${\sim}$73% in case of grain, pod and stem, respectively. Crop moisture content was negatively correlated with header loss, but positively correlated with threshing loss. In contrary, stem moisture content showed positive correlations with total loss, threshing loss and separation loss. Working speed was positively correlated with header loss. Total flow rate, pod flow rate and stem flow rate were highly correlated with threshing loss and separation loss. However, grain flow rate did not show any correlation with total loss. According to the principal component analysis, two principal components were derived as components with eigenvalues greater than 1.0. The contribution rates of the first and the second components were 52.7% and 38.9%, which accounted for 91.6% of total variance. As a contributive factor influencing total loss of rapeseed mechanical harvesting, a crop moisture content factor was greater than a crop flow rate factor. The stepwise multiple regression analysis for total loss was conducted using crop moisture content factor, crop flow rate factor and coefficient. However, the model did not show any correlation among independent and dependent factors ($R^2$=0.060).