• Proceedings of the Korean Society of Precision Engineering Conference
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• 1995.10a
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• pp.650-654
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• 1995

In this study, in order to measure energy-absorbing charactistics in collapse test of CFRP thin-walled laminates and interpretate the cause of decreasing age when collapse test is carried out under the environments of high temperatures and hygrothermals, the moisture absorbing behavior according to the variety of orientation angel is observed and collapse characteristics is compared with the influence of high temperatures and hygrothermals. Especially, we supposed to clearly understand reationship between collapse characteristics in proportion to the variety of orientation angel and moisture absorbing. The value of the maximum loading, mean loading,rate of energy absorption energy per unit volume and mass in CFRP thin-walled laminates on the high temperatures and hygrothermals is measured lower than under no moisture absorbing. The maximum collapse loading in dynamic impact test is taken measurement lower than in static collapse test regarding compared with collapse characteristics conformity with the variety of the CFRP circular laminates in high temperatures and hygrothermals. But the absorbed energy per unit mass and volume is almost same and the biggest amount of energy is shown in the CFRP circular laminates with orientation angel of 15 .deg.. Therefore, in the case of use to CFRP circular laminates with axisymmetric mode, CFRP thin-walled structal members with orientation angel of 10 .deg. , 15 . deg. are generally useful.

• Journal of the Korean Society of Safety
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• v.13 no.2
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• pp.30-38
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• 1998

In this study, in order to measure energy-absorbing characteristics in impact test of CFRP thin-walled laminates and interpret the cause of decreasing age when collapse test is carried out under the environments of high temperatures and hygrothermals, the moisture absorbing behavior according to the variety of orientation angle is observed and impact collapse characteristics of no moisture absorbing status is compared with that under the environments of high temperatures and hygrothermals. Especially, we try to obtain quantitative design data to develop CFRP thin-walled laminates with energy characteristics of optimum impact absorbing. The value of the maximum loading, mean loading, rate of energy absorption energy per unit volume and mass in CFRP thin-walled laminates on the high temperatures and hygrothermals is measured much lower than under no moisture absorbing. The maximum collapse loading in dynamic impact test is taken measurements lower than in static collapse test CFRP circular laminates in high temperatures and hygrothermals. But the absorbed energy per unit mass and volume is almost same each other and the biggest amount of energy is shown in CFRP circular laminates with orientation angle of $15^{\circ}$. Therefore, in the case of using CFRP circular laminates with axisymmetric mode, CFRP thin-walled structural members with orientation angle of $10^{\circ}$, $15^{\circ}$ has generally best condition.

• Journal of the Korean Society of Food Science and Nutrition
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• v.43 no.9
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• pp.1407-1414
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• 2014

Physicochemical properties of rice-based expanded snacks extruded with rice flour, high amylose starch, and isolated soy protein were investigated using a twin-screw extruder. The ingredients were extruded at various feed moisture contents (19~23%) and screw speeds (200~400 rpm) at a constant feed rate (43.4 kg/hr). Bulk density and apparent density of rice snacks were 0.06~0.21, and 0.55~0.65 respectively. Bulk density, apparent density, water absorption index, and breaking strength of rice snacks increased with increasing feed moisture content and decreasing screw speed. However, expansion and water solubility index of rice snacks increased with decreasing feed moisture content and increasing screw speed. Hunter's color L values of rice snacks was lower with increasing screw speed at feed moisture contents of 19% and 21%, but was not significantly different from a feed moisture content of 23%. On the other hand, a and b values of rice snacks were higher with increasing screw speed a feed moisture content of 19%. X-ray diffraction intensity of rice snacks decreased with decreasing feed moisture content and increasing screw speed. X-ray diffraction of rice snacks was V-type at feed moisture contents of 19% and 21% and screw speeds of 300, and 400 rpm. In the microstructure of the cross section of rice snacks, air cells in rice snacks were not well formed, and cell walls were thicker with increasing feed moisture content and decreasing screw speed.

• 보존과학연구
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• s.7
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• pp.56-86
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• 1986

The aim of this study is to scientifical conservation for the Sin An Ship. The test object is Pinus massoniana and Cunninghamia lanceolata of Sin An Ship's timber .Comtrast object is water soaked fresh wood of Pinus densiflora and Cryptomeria japonica The results were as follows.1. M. C is 280.9% in high degraded Planking board,237.5% in low degraded Planking board,158.6% in fresh wood of Pinus densiflora,222.6% in Bulkhead167.3% in fresh wood of Cryptomeria japonica2. Absorption rate of P.E.G is good at heating condition ($55∼60^{\circ}C$), especially in highdegraded wood.3. The dimensional change of wood during air drying is somewhat shrinked That's 7.22% in low degraded Planking board9.8% in high degraded Planking board and 4.11% in water soaked Pinus densiflora.4. The dimensional change of wood during P.E.G treatment is mostly swollen of wery small quantity.5. Salinity in desalinization tank showed below 50 p.p.m. It's indicate the end of desalinization treatment.6. Filtration with filter paper was possible up to 40% concentration only. Key words :M.c ; Moisture Content, Absorption rate, Dimension change, Salinity, Filtration.

• Textile Coloration and Finishing
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• v.14 no.5
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• pp.268-276
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• 2002

Poly(trimethylene terephthalate)(PTT) and Poly(ethylene terephthalate)(PET) fibers were annealed at various temperatures ranging from $100^\circ{C}$ to $230^\circ{C}$ for 10 min under tension and tension free. Dyeing rates and absorption isotherms of both fibers were obtained with C.I. Disperse Red 60 at 100, 120 and $130^\circ{C}$ in water system. Also X-ray diffraction pattern, moisture regain and water absorption were investigated. The dyeing rate of PTT fiber is faster than PET fiber, and dyeing of PTT fiber begin at lower temperature compared to PET fiber. The absorption isotherms from both fibers with disperse dye we nearly linear up to the saturation dye uptake, which increase with dyeing temperature. Equilibrium dye uptake of PTT fiber annealed under tension above $180^\circ{C}$ was remarkably decreased because of a changes in the fine structure of fiber. The intensities of X-ray diffraction peaks of both annealed fibers were increased with increasing in annealed temperature. The reflections observed at $2\theta$=$15.8^\circ$, $24^\circ$ and $25.2^\circ$ were assigned reflection of crystal at the planes of (010), $(1\bar02,\;\bar112),\;and\;(\bar13,\; \bar113)$ respectively, and the peak became sharp with heat setting temperature.

• Geomechanics and Engineering
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• v.38 no.3
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• pp.307-317
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• 2024

To get a better understanding of the effect of drying-wetting cycles (DWC) on the mechanical behaviors of silty clay hiving different initial moisture content (IMC), the direct shear tests were performed on sliding band soil taken from a reservoirinduced landslide at the Three Gorges Reservoir area. The results indicated that, as the increasing number of DWC, the shear stress-displacement curves type changed from strain-hardening to strain-softening, and both the soil peak strengths and strength parameters reduced first and then nearly remain unchanged after a certain number of DWC. The effects of DWC on the cohesion were predominated that on the internal friction angle. The IMC of 17% is regarding as the critical moisture content, and the evolution laws of both peak shear strength and strength parameters presented a reversed 'U' type with the rising of the IMC. Based on it, a strength deterioration evolution model incorporating the influence of IMC and DWC was developed to describe the total degradation degree and degradation rate of strength parameters, and the degradation of strength parameters caused by DWC could be counterbalanced to some extent as the soil IMC close to critical moisture content. The microscopic mechanism for the soil strength caused by the IMC and DWC were discussed separately. The research results are of great significance for further understanding the water-weakening mechanicals of the silty clay subjected to the water absorption/desorption.

• Proceedings of the Korea Concrete Institute Conference
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• 1998.10b
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• pp.883-887
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• 1998

Hydration is the main reason for the growth of the material properties. A exact parameter to control the chemical and physical process is not the time, but the degree of hydration. Therefore, it is reasonable that development all material properties should be formulated in terms of degree of hydration. Mathematical formulation of degree of hydration is based on combination of reaction rate functions. The effect of moisture conditions as well as temperature on the rate of reaction is considered in the degree of hydration model. This effect is subdivided into two contributions: water shortage and water distribution. The former is associated with the effect of on the progress of hydration. The water needed for progress of hydration do not exist and there is not enough space for the reaction products to form. The latter is associated with the effect of free capillary water distribution in the pore system. Physically absorption layer does not contribute to progress of hydration and only free water is available for further hydration.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.38 no.3
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• pp.137-142
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• 2005

New types of patties were prepared with surimi and crab paste, and then characterized. With an increase of additional ratios of crab paste, the moisture (64.8 to $61.5\%$) of the patties slightly decreased while the ash contents (2.3 to $3.7\%$) increased. The Hunter's color values of the patties decreased in lightness (L value, 58.79 to 54.27) but increased in redness (a value, -2.77 to 3.54). Thus, the patties that had added crab paste appeared slightly more reddish. According to the increasing of additional ratios of crab paste, sensory scores on color and flavor increased whereas the texture score decreased. From the above results, based on physical properties and sensory evaluation, the desirable additional ratio of crab paste for preparing patty was $15\%$. The calcium and phosphorus contents of the patties with the addition of $15\%$ crab paste were 148.8 mg/100 g and 139.6 mg/100 g, respectively, and their ratio (approximately 1:1) was the optimal range in body absorption efficiency. The calcium absorption rate with the $15\%$ additions was 4.9 times higher than that of the patty with no additions. Total amino acid content (16,302 mg/100 g) of the $15\%$ additions showed no difference to the patty without additions, and the major amino acids were aspartic acid, glutamic acid, leucine and lysine. Exceptionally, the cysteine content of the patty with the $15\%$ crab paste additions was 2 times higher than that found in the patty without crab paste. The major fatty acids were 16:0, 18:1n-9 and 18:2n-6 of the total lipids, and there was no difference between the patties with and without crab paste. The above results showed that crab paste can be used as a crab surimi gel source.

• Horticultural Science & Technology
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• v.34 no.3
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• pp.363-371
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• 2016

Tabulis [Astilboides tabularis (Hemsl.) Engl.] has the potential for becoming a useful horticultural crop. This study was conducted to classify the seed dormancy types and to identify the germination conditions that improve the horticultural usefulness of this plant. We found that A. tabularis (Hemsl.) Engl. produced undifferentiated embryos and had a low germination rate of under 50%. In addition, water submersion led to moisture absorption. Therefore, A. tabularis seeds were designated as morphologically dormant. The germination rate was highest (86.3%) at $30^{\circ}C$ under light conditions. Higher temperatures generally led to an acceleration of the germination process, regardless of light condition. To improve the germination rate, seeds were submerged in various concentrations of growth regulators, such as $GA_3$ and kinetin, as well as minerals such as $KNO_3$ and KCl. An analysis of germination characteristics at $30^{\circ}C$ under light conditions revealed that treatment with 200 and $500mg{\cdot}L^{-1}GA_3$ led to an excellent germination rate of 97.0%. Treatment with $100mg{\cdot}L^{-1}GA_3$ led to a better germination rate than the control as well. However, treatment with kinetin, $KNO_3$, and KCl had no effect on germination, regardless of concentration.

• Journal of the Korean Institute of Landscape Architecture
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• v.32 no.6 s.107
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• pp.109-116
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• 2005

This study was conducted to examine the growth and physiological characteristics of Asplenium scolopendrium native fern as affected by irrigation times and soil media as an environment modeled on habitate where was sunken-condition. 1. Light intensity was lower in sunken than in non-sunken, but air humidity was higher in sunken about $2040\%$. Soil moisture content was higher with the leaf mold in sunken irrigating 2 times/week. The results of chemical analysis of medium showed that EC, pH, organic matter content, total nitrogen, CEC, Exch-Ca, Exch-Mg and Exch-K were higher with leaf mold than sud: leafmold and field soil: sud: leaf mold. 2. In the case of irrigation 2 times/week Asplenium scolopendrium grew well sunken more than non-sunken. As non-sunken condition similar with, 7 times/week irrigation, plant height, frond width, frond length and stipe length increased. In case of soil media, growth of Asplenium scolopendrium was better with leaf mold than that of sand: leafmold or field soil: sand: leaf mold. 3. In the case of irrigation 2 times/week photosynthetic rate, $CO_2$ absorption rate and water efficiency were higher with non-sunken than that of sunken, expect of stomatal conduction, $CO_2$ use efficiency. The physiological characteristics of Asplenium scolopendrium were highest in non-sunken irrigating 7 times/week In case of soil media, physiological activity was higher with leaf mold than sand: leafmold or field soil: sand: leaf mold.