• Journal of the Korean Wood Science and Technology
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• v.23 no.4
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• pp.67-73
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• 1995

This study was undertaken to investigate the effect of heat treatment on the dynamic viscoelasticity of three species of Phyllostachys bambusoides, Phyllostachys nigra var. henonis and Phyllostachys pubescens, grown in southern Korea. The bamboo was treated for 3~24 hours at $60{\sim}180^{\circ}C$, and then was treated in a climatic chamber for 3~48 hours at $40^{\circ}C$ and 95% relative humidity. The results obtained are summarized as follows : 1. Dynamic Young's modulus decreased with increasing temperature and duration of the heat treatment. 2. Internal friction decreased with increasing treatment duration. 3. Moisture absorption decreased with increasing temperature and duration of the heat treatment. 4. Dynamic viscoelasticity decreased, whereas internal friction slowly increased, with increasing moisture content.

• Fashion & Textile Research Journal
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• v.11 no.3
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• pp.481-487
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• 2009

The purpose of this study is to improve the defects of dyeable polypropylene(DPP) fabric by heat setting and to describe the change of physical properties of DPP fabrics. The thermosetting was carried out in autoclave from 100 to $140^{\circ}C$ temperature range for 2 min. In this study, we investigated the effect of the thermosetting temperatures on the structural, thermal, mechanical properties(e.g., the strength and elongation) and dyeability of DPP fabrics. The melting energy(J/g), the tensile strength was found to increase with increasing temperature of thermosetting. The diffraction peak at Bragg angle($2{\theta}$) about $13.8^{\circ}$ were very strong and diffraction intensity increased with increasing thermosetting temperatures. And d-spacing and half-width decreased with increasing thermosetting temperatures. On the other hand, the dyeability(K/S) and crease recovery decreased with an increasing thermosetting temperatures.

• Journal of Korea Foundry Society
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• v.23 no.3
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• pp.130-136
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• 2003

Rheocasting of AZ91D magnesium alloys yielded the microstructure consisted of the spherical primary particles in the matrix which is different from conventional casting. Rheocast ingots were produced under various processing conditions using batch type rheocaster. Morphology of primary particles was changed from rosette-shape to spherical shape with increasing stirring rate$(V_s)$ and decreasing isothermal stirring temperature$(T_s)$. With increasing $V_s$, more effective shearing between the particles occurred rather than the agglomeration and clustering, so the primary particle size decreased. But with decreasing $T_s$, primary particle size increased mainly due to sintering and partially Ostwald ripening. The sphericity of primary particles increased with increasing $V_s$ and decreasing $T_s$ due to enhanced abrasion among the primary particles. The uniformity of primary particle size increased with increasing Vs and $T_s$.

• Journal of Korean Society for Atmospheric Environment
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• v.11 no.2
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• pp.171-178
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• 1995

The hydrodesulfurization (HDS) of dibenzothiophene (DBT) were performed simultaneously over CoPtMo/LaY catalyst under high H$_{2}$ pressure. The structure and physical properties of this catalyst were characterized using XRD, IR and surface area analyzer. The origin of acid site was mainly Bronsted. The structures of impregnated molybdenum and platinum were deactivated by DBT to MoS$_{2}$ and PtS, respectively. The activities of the HDS and the hydrocracking increased with increasing temperature and pressure. They decreased with increasing the DBT mole ratio(DBT/n-heptane). They remained constant with increasing the H$_{2}$/H.C. mole ratio. With increasing pressure and DBT mole ratio, the products of secondary cracking increased. To perform simultaneous HDS and hydrocracking effectively, the optimum condition were 500.deg.C, 4MPa.

• Applied Chemistry for Engineering
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• v.3 no.2
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• pp.341-348
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• 1992

PVC was compounded with various crosslinking agents, plasticizers and acrylonitrile butadiene rubber(NBR) to evaluate their effects on the radiation gel percent, elongation at break, heat distortion and heat shrinkage. Gel yield of PVC increased with increasing unsaturation levels per molecular weight of crosslinking agents while PVC containing NBR was more sensitive to crosslinking than PVC itself regardless of the types of crosslinking agents and plasticizers. It was found that gel percent was increased with increasing radiation dose, while heat distortion was decreased with increasing gel percent. Heat shrinkage was increased with decreasing stretching temperature and increasing annealing temperature.

• Journal of the Korean Society of Food Culture
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• v.32 no.5
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• pp.446-452
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• 2017

This study was conducted to evaluate the quality characteristics and antioxidant activities of salad dressing prepared with acaiberry powder (0, 1, 3, and 5%). The pH and titratable acidity increased as the acaiberry powder increased. The sugar content showed no significant differences between samples. The viscosity was lowest in the controls and increased with increasing amounts of the acaiberry powder. The lightness and yellowness values decreased, while the redness values increased with increasing amounts of acaiberry powder. The total polyphenol content ranged from 10.26-45.19 mg GAE/100 g, increasing with increased acaiberry powder levels. The antioxidant activities measured via DPPH radical scavenging activity, reducing power and FRAP also increased with increasing acaiberry powder concentrations. Finally, a consumer acceptance test revealed that up to 3% acaiberry powder could be added to salad dressing to provide high antioxidant activity without sacrificing sensory quality.

• Journal of Korea Foundry Society
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• v.4 no.2
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• pp.89-95
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• 1984

A Study on the Mechanical Properties of Molding Sand with Various Water/Clay Ratio A standard sample of molding sand was prepared by adding a various amount of bentonite, which has water/clay ratio from 0.4 to 0.6, into artificial sand, Hanyoung #6. The results obtained by measuring the room temperature properties of green mold are as follows. 1. This compressive strength of green molds which have 4% and 10% of bentonite decreased with increasing water/clay ratio, but the maximum strengths of 4.3 (psi) and 7.2 (psi) were observed in the samples with 6%, 8% bentonite respectively when the water/clay is 0.45. 2. The optimum water/clay ratio for strength and permeability increased from 0.4 to 0.5 with increasing clay. 3. The green compressive strength was proportional to the hardness. 4. Deformation increased with increasing water/clay ratio. 5. Flowability decreased with increasing water/clay ratio and clay content in molding sand.

• Biomolecules & Therapeutics
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• v.4 no.3
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• pp.232-238
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• 1996

The physical dependence potency of DA-5018, a non-narcotic analgesic agent, was tested in mice dosed with 0.5 and 4 mg/kg/day for 2 months and daily increasing doses of 1, 2, 4, 6, 8 and 10 mg/kg over 10 days. Physical dependence was assessed taking natural withdrawal induced morphine-type abstinence (jumping, falling, biting or backward locomotion, rearing etc.) as well as barbiturates-type abstinence (body weight reduction, convulsion, ataxia etc.) into consideration. The results were compared with those after the same daily increasing doses of morphine. DA-5018 did not show evidence of physical dependence liability or abuse potential as measured by morphine-type or barbiturate-type abstinence signs following daily increasing or 2-month repeated administration. On the other hand, daily increasing doses of morphine produced physical dependence and the dependent state disappeared about 6 hours after the start of withdrawal signs. In the single dose suppression test, a single dose of morphine completely suppressed natural withdrawal signs that appeared in morphine-dependent animals. Therefore, these results indicate that DA-5018 does not have abuse potential and physical dependence liability.

• Journal of Fisheries and Marine Sciences Education
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• v.6 no.2
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• pp.161-182
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• 1994

The steady rise in life expectancy resulting from progress in medical science and economic growth and improved living conditions is responsible for large and increasing-number of older peoples in our country. The older peoples who are increasing make up a large percentage of our total population. Now a day the percentage of older people 60 and 65 years old over compose around 8.7% and 5% of the total population in each. In spite of such a rapidly increasing trend of older population, there has had no provisions for elderly welfare in our country. The reason why some children do not want to take care of their older parents, and the other is the lack of elderly welfare, are responsible for large and increasing anxiety of livelihood and alienation to the number of older peoples. As mentioned above, especially studying Swedish elderly welfare model of many developed countries, it intend to provide many of the useful materials to make the elderly welfare systems in our country. The main research for Swedish elderly welfare are as follows : (1) Old age pension systems (2) Social service systems (3) Health care service systems (4) Housing care service systems.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.29 no.1 s.232
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• pp.16-26
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• 2005

Air-cooled heat sinks are employed in many electronic cooling applications since they provide significant heat transfer enhancement and operational flexibility. Strip-shaped fin heat sink is of interest and needs to be investigated as general cooling products for more applicability. The purposes of this study are to evaluate heat sink performance without bypass flow condition and to determine optimal heat sink geometries. The results show that the decreasing rate of thermal resistance of a heat sink decreases with increasing inlet air velocity, and the increasing rate of pressure drop increases with increasing inlet air velocity, but is not affected by input power. The increasing rate of optimal longitudinal fin spacing is larger than that of transverse fin spacing. The strip fin heat sink tested in this study showed better cooling performance compared to that of other plate fin type.matism. 2004; 50(11): 3504-3515.