• Magazine of the Korean Society of Agricultural Engineers
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• v.23 no.3
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• pp.96-104
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• 1981

In order to investigate the characteristics of the shear strength of the unsaturated cohesive soils which has mean characters of sand and clay widely used for banking, I selected soil samples from An-sung district and, against it, performed direct shear test and unconfined compression test changing grain size, compaction energy and moisture content and also performed triaxial compression test under optimum moisture content. The results are as follows; 1.As the passing percent of the No. 200 sieve increased from 23.6% to 56.1%, cohesion increased from 0. 202kg/cm2 to 0. 398kg/cm2 under the direct shear test and from 0.38 kg/cm2 to 1. 05kg/cm2 under the tria4al compression test, internal friction angle decreased from 44. 78$^{\circ}$ to 34. 34$^{\circ}$ under the direct shear test and from 31. 88$^{\circ}$ to 13. 31$^{\circ}$ under the triaxial compression test. 2.Cohesion showed it's maximum value around OMC and internal friction angle showed a tendency to increase according to the decrease of water content but it's increasing ratio was relatively slow. 3.Decreasing ratio of cohesion and internal friction angle was relatively sensitive according to the decrease of compaction energy. 4.The smaller of the vertical stress and the coarser of the grain size of samples, changing of the volume showed a tendency to increase and as the increase of water content, the shear displacement (dh) at failure shear stress ($\tau$f) showed maximum and the $\tau$f-dh curve was gentle. 5.To synthesize the results of the direct shear test and the triaxial compression test, cohesion showed higher under the triaxial compression test and internal friction angle showed a tendeney to appear higher under the direct shear test. It seems that we can get correspondent results by removing the side friction of mold with soils and adjusting the vertical stress and shearing speed under the direct shear test.

• Food Engineering Progress
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• v.21 no.2
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• pp.150-157
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• 2017

The objective of this study was to determine the effect of moisture contents (40, 50, 60%) and $CO_2$ gas injection (0 and 800 mL/min) on physicochemical properties of extruded soy protein isolate (SPI). The expansion ratio and the specific length increased, but piece density decreased with the increase in $CO_2$ gas injection from 0 to 800 mL/min at both 40 and 50% moisture contents. On the contrary, the expansion ratio and the specific length decreased, but piece density increased with the increase in $CO_2$ gas injection from 0 to 800 mL/min at 60% moisture content. Extruded SPI with $CO_2$ gas injection at 800 mL/min had small cell size and higher amount of cell than extruded SPI without $CO_2$ gas injection. The water holding capacity and nitrogen solubility index increased, and the integrity index and the texture decreased with the increase in $CO_2$ gas injection from 0 to 800 mL/min. In conclusion, extruded SPI with the $CO_2$ gas injection at 800 mL/min showed better expansion properties and cell formation than extruded SPI without the $CO_2$ gas injection.

• Journal of the Korea Concrete Institute
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• v.22 no.2
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• pp.159-169
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• 2010

A multiphysics model analysis including moisture transport, heat transfer and solid mechanics and experiments on the normal and light weight concrete were carried out in order to study the effect of preabsorbed water in the light weight aggregates on the drying and shrinkage characteristics of concrete. Consequently, with fixed water-cement ratio, loss of water content of normal and light weight concrete were compared and the results showed that the lightweight concrete lost less moist than the normal concrete in early age and long term which was by moist supply effect. Accordingly, shrinkage strain size and distribution of lightweight concrete were decreased, and shrinkage reducing effect was efficient in early age with water cement ratio 0.3 and in both early age, and long term with water cement ratio 0.5. The comparison of analysis results and exaperimental results indicate that characteristic values of moisture transport and the relation humidity and shrinkage strain from this study are resonable for application for other differential shrinkage analysis in lightweight concrete.

• Journal of the Korean Society of Food Science and Nutrition
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• v.45 no.8
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• pp.1170-1176
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• 2016

The aim of this study was to investigate the effects of screw speed, moisture content, and die temperature on the physical properties of extruded soy protein isolate. Extrusion conditions were moisture content (20 and 25%) and die temperature (120, 130, and $140^{\circ}C$) at a fixed screw speed of 250 rpm. The other extrusion conditions for screw speed (150, 200, 250, 300, and 330 rpm) were a fixed moisture content and die temperature of 30% and $140^{\circ}C$, respectively. Specific mechanical energy input decreased as die temperature increased from 120 to $140^{\circ}C$, whereas specific mechanical energy input increased as screw speed increased from 150 to 330 rpm. Expansion ratio and specific length increased as die temperature increased. Breaking strength decreased as die temperature increased and moisture content decreased. A lower moisture content resulted in a greater color difference. Integrity index increased as die temperature increased from 120 to $140^{\circ}C$ and moisture content decreased from 25 to 20%. Nitrogen solubility index decreased as screw speed increased from 150 to 330 rpm. Nitrogen solubility index was lowest at $2.83{\pm}0.51%$ as screw speed decreased to 150 rpm. In conclusion, moisture content was a more important factor than die temperature for texturization of soy protein isolate.

• Korean journal of food and cookery science
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• v.24 no.1
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• pp.31-38
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• 2008

Sulgidduk samples made with additions of 1, 2, 3, 4, and 5% Ulmus cortex powder, and a control, were examined for quality characteristics such as moisture content, color, gelatinization properties, textural characteristics, and consumer acceptance, in order to determine the optimal ratio of Ulmus cortex powder in the formulation. The moisture contents among the samples were not significantly different, ranging from 40.57 to 42.37%, and increased as the Ulmus cortex powder content increased. For the color values, lightness decreased and yellowness and redness increased with increasing Ulmus cortex powder content. With regard to the gelatinization properties, peak viscosity (P), trough viscosity (T), final viscosity (F), breakdown, and consistency increased with increasing amounts of Ulmus cortex powder. Pasting temperature, time to peak viscosity, and setback presented decreasing tendencies with the additions of Ulmus cortex powder. For the textural characteristics, increasing Ulmus cortex powder content presented decreases in hardness, springiness, and chewiness however, adhesiveness, cohesiveness, and gumminess were not significantly different among samples. In the consumer acceptance test, the scores of all evaluated characteristics decreased as the ratio of Ulmus cortex powder increased. However, the intensity ratings for the 1 and 2% Ulmus cortex powder samples showed the opposite effect, obtaining fairly good scores. In conclusion, the results indicate that adding $1{\sim}2%$ Ulmus cortex powder to Sulgidduk is optimal, providing good physiological properties and reasonably high consumer acceptability.

• Magazine of the Korean Society of Agricultural Engineers
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• v.43 no.5
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• pp.132-144
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• 2001

Iln order to figure out criteria of bentonite for using as impervious material of waste landfill, laboratory experiments were performed to reveal the geotechnical properties of soil-bentonite mixtures such as compaction test, direct shear test, unconfined compression test, triaxial compression test, consolidation test and permeability test. The results of the study are summarized as follows ; 1. Based on the compaction test, optimum moisture content increased with the increase of bentonite content, but maximum dry density decreased. 2. In unconfined compression test, the maximum strength of the soil-bentonite mixtures appeared at 10% bentonite content. The correlation equation between stress($\sigma$) and strain($\varepsilon$) of the soil-bentonite mixtures is given by ; $\sigma=\frac{a\cdot\varepsilon}{\varepsilon^n+b}$ 3. In shear test of the mixtures. the shear strength showed an increasing trend with increase of bentonite content and the maximum shear strength appeared at 10% bentonite content. 4. In consolidation test, the coefficient of compressibility $(a_v)$$(m_v)$$(C_v)$

• Food Science and Preservation
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• v.10 no.3
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• pp.320-325
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• 2003

This study was conducted to optimize sugaring process of yam for development of new snack product and enhancement acceptability. Three variables by five level central composite design and response surface methodology were used to determine optimum conditions for sugaring time, temperature and concentration. Optimization of the process was conducted using the combination of the moisture content, solid content, color and rehydration ratio. The regression polynomial model was suitable (P>0.05) model by Lack-of-Fit analysis with highly significant. To optimize the process, based on surface response and contour plots, superimposing the individual contour plots for the response variables. The optimum conditions for this process were 5.5 hours and 58％ at 40$^{\circ}C$ under the optimum of restricted variables as moisture content was 66 to 70, solid content was 25 to 30％, L value was above 75, a value was -2.1 to -2.4, b value was above 5 and rehydration ratio was 200 to 250.

• Journal of the Korean Society of Food Science and Nutrition
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• v.25 no.5
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• pp.810-816
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• 1996

This study was conducted to measure the hydration characteristics at $20^{\circ}C$ and investigated the effect of water to rice ratio(v/w) on the texture properties of cooked rice of ten different varieties based on maturity. Water absorptions during soaking were completed between 30min and 35min at $20^{\circ}C$. The ranges of equilibrium moisture content were between 0.3247g $H_2O/g$ dry matter and 0.3577g H201g dry matter. During the cooking process, the water content of cooked rice increased 6~7% with increased the ratio of water to rice from 1.4 to 1.6(v/w). The hardness(H) of cooked rice decreased, while the stickiness(-H) and -H/H ratio increased with increased ratio of water to rice.

• Journal of Animal Environmental Science
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• v.21 no.3
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• pp.99-104
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• 2015

According to the volumetric mixing rate of dairy cow manure (DCM) and moisture control materials such as decomposed manure (DM) and sawdust (S), 6 reactors (DCM only (R1), DCM : DM = 1:1 (R2), DCM : DM = 1.5:0.5 (R3), DCM : DM = 0.5:1.5 (R4), DCM : DM:S = 1:0.5:0.5 (R5) and DCM : S = 1:1 (R6)) were used for composting of dairy cow manure. Among the composting reactors, composting reactor of R5 was shown the highest temperature of the compost as a $66^{\circ}C$ during composting period. After 3 weeks composting, moisture content of R5 and R6 were 51% and 51.3%, respectively. These values were satisfied with the moisture content standard of livestock manure compost of Korea. We concluded that decomposed manure may be a good moisture control material for dairy cow manure composting when it is used in mixture with sawdust. The optimum volumetric mixing ratio of dairy cow manure and moisture control materials was 50% of livestock manure, 25% of decomposed manure and 25% of sawdust.

• Korean journal of food and cookery science
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• v.20 no.1
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• pp.49-56
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• 2004

Neuti-dduk is a steamed rice cake made of nonglutious rice How, with Neuti leaves powder, sugar, and water. The objective of study was designed to seek the best recipe to make Neuti-dduk The procedure was as follows Neuti-dduk containing different ratios of the above mentioned ingredients, such as Neuti leaves powder (4, 8, and 12g), sugar and water. The most desirable recipe was determined after sensory examinations and mechanical tests to measure the texture, moisture content and colorimeter. The results of the sensory evaluation showed the Neuti-dduk containing 8g Neuti leaves powder, 20g sugar 20 and 45$m\ell$ water had the highest scores in overall acceptability, color and flavor preference. In the textural analysis the hardness, adhesiveness and cohesiveness of the Neuti-dduk decreased on the addition of increasing amounts of Neuti leaves powder. The moisture content of Neuti-dduk with 4g Neuti leaves powder was higher than that with 12g. The L- and a-values of Neuti-dduk were increased by decreasing the amount of Neuti leaves powder. The overall quality of the sensory examination of Neuti-dduk in relation to the amount of Neuti leaves powder had positive correlation with the moistness, but negative correlations with the L-value andmoisture content. (Eds note: would these 2 highlighted features not be related; if so, why does one have a positive and the other a negative correlation\ulcorner) From the results of these tests, the most desirable recipe for the Neuti-dduk was 8g of Neuti leaves powder, 20g of sugar, 45$m\ell$ of water and2g of salt, for every 200g of rice powder. The moisture content of this recipe was 42.18％.