• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.40 no.5
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• pp.36-41
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• 2008

Multi-ply sheet forming has many advantages including the possibility of using wide range of materials in a given structure, lowering production cost, making higher grammage products and so on. But, incorrect structure of sheet makes flow resistance higher so that it shows poor dewatering in press section. One of major factors that affect sheet structure and dewatering property is fines content in each layer. We, therefore, examined the press dewatering of multi-ply sheet that has the different fines content in each layer and the effect of fines distribution on physical properties of sheet to find a technology for optimum utilization of raw materials. In case of two layered sheet, the sheet which was composed of layers with the different flow resistance showed higher dewatering rate than one which has the same flow resistance. And the more difference in fines content for layers existed, the more dewatering occurred. For three layered sheets, dewatering is mainly dependent on fines content of bottom layer. Strength properties were affected by dewatering degree and multi-ply sheet structure.

• Journal of The Korean Society of Agricultural Engineers
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• v.46 no.7
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• pp.55-67
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• 2004

In this paper, the flowability, strengths, impact resistance and sulfuric acid resistance of steel fiber reinforced high performance concrete (SFHPC) for the steel fiber content and fly ash and blast furnace slag as admixtures were presented. For evaluating flowability particularly, tests of slump flow, box-type passing ability and L-type filling ability were performed. The slump flow of SFHPC was some decreased with increase of the steel fiber content. At the box-type passing ability, the difference of box height of SFHPC is greatly increased with increasing the fiber content. The L-type filling ability of SFHPC was not excellent above $0.75\% of the steel fiber content. Also, the compressive strength of SFHPC was decreased with increase of the steel fiber content, but the flexural strength of SFHPC was much higher than that of the concrete without the steel fiber. At the impact resistance, drop number of SFHPC for reaching final fracture was increased with increase of the fiber content. Also, the drop number for reaching initial fracture of lmm was increased with increase of the fiber content. At the sulfuric acid resistance, 4-week weight change of SFHPC with the steel fiber was almost similarity that of HPC without the steel fiber and was in the range of 73.6 to 81.5.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.10 no.2
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• pp.91-95
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• 2000

The effects of argon gas flow on the axial temperature gradient near the interface, the oxygen concentration, and the radial oxygen uniformity was investigated for 8-inch CZ silicon growth. As argon flow rate was increased, the temperature gradient was increased in the crystal near the crystavmelt interface and the oxygen content in the crystal was decreased. But the radial oxygen uniformity was deteriorated. It was found that argon flow is one of the important growing parameters to affect the quality of crystals such as oxygen content and uniformity.

• Water for future
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• v.24 no.1
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• pp.109-117
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• 1991

The governing equation of flow in porous media is developed on the bases of the continuity equation of fluid for transient flow through a saturated-unsaturated zone, and substitution of Darcy's law. The numerical solutions are obtained by finite element method based on the Galerkin principles weighted residuals. The analysis are carried out by using the unsteady storm data observed and rainfall intensities which are obtained by using the rainfall excess model in considering of the initial losses. The functional relationships between the hydraulic conductivity, capillary pressure head and volumetric water content are applied to the flow of water through unsaturated soil varied with changes of water content.

• Journal of Biosystems Engineering
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• v.24 no.1
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• pp.31-40
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• 1999

The objective of this study were to develop a cooling simulation model for fixed-bed of rough rice and to analyze the factors affecting cooling time of rough rice. A computer simulation model based on equilibrium conditions between grain and air was developed to predict temperature and moisture content changes during cooling of rough rice. the result of t-test showed that there were no significant differences between predicted and measured temperature changes on significance model agreed well with measured values. This cooling simulation model was applied to analyze the effect of some factors, such as air flow rate, cooling air temperature and humidity, initial grain temperature and moisture content, and bed depth, on cooling time of rough rice. Cooling rate increased with increase of air flow rate and bed depth whereas it decreased with increase of cooling air temperature and humidity and initial grain temperature. Among these factors, the most important factor was air flow rate. Specific air flow rate of 0.35㎥/min㎥ was required for cooling rough rice in 24 hours.

• Proceedings of the Korea Concrete Institute Conference
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• 2005.05b
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• pp.73-76
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• 2005

This study aims to suggest a simple and convenient design for a mix proportion method for high performance concrete by determining the optimum fine aggregate ratio and minimum binder content based on the maximum density theory. The mix design method introduced in this study adopted the optimum fine aggregate ratio with a minimum void and binder content higher than the minimum binder content level. The research results reveal that the method helps to reduce trial and error in the mixing process and is a convenient way of producing high performance concrete with self filler ability. In an experiment based on the mix proportion method, when aggregate with the fine aggregation ratio of 41$\%$ was used, the minimum binder content of high performance concrete was 470kg/$m^{3}$ and maximum aggregate capacity was $0.657m^{3}/m^{3}$. In addition, in mixing high performance concrete, the optimal slump flow to meet filler ability was 65$\pm$5cm, V load flow speed ranged from 0.5 to 1.5.

• Proceedings of the Korean Society of Computer Information Conference
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• 2023.07a
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• pp.119-122
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• 2023

게임 이용자가 재미를 느끼고 몰입하며 그 재미가 오래 유지되도록 하는 것은 많은 게임 디자이너의 관심사이다. 본 논문에서는 비교적 적은 개발 비용으로 긴 몰입 기간을 만들어낸 몬스터 헌터: 월드를 통해 이를 가능토록 하는 게임 디자인 기법 "반복 플레이 동기 부여", "숙련도 영역 전환"의 두 가지를 제안한다.

• The Korean Journal of Physiology and Pharmacology
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• v.5 no.5
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• pp.423-431
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• 2001

Some recent investigations revealed that vasodilatory action of adenosine is mainly not mediated by surface A2 receptor and suggested the existence of an intracellular action site. In the present study, we tried to differentiate intracellular from extracellular site of adenosine action in the regulation of coronary flow. In perfused rabbit hearts, concentration-response curve of coronary flow to exogenous adenosine was constructed in the presence or absence of dipyridamole, an inhibitor of transmembrane purine transport. Inhibition of cellular adenosine uptake by dipyridamole suppressed the increase of flow rate while enhancing the decrease in heart rate induced by exogenous adenosine. In another series of experiments, perfused rabbit hearts were subjected to energy deprivation in order to increase the production of endogenous adenosine. Energy deprivation along with dipyridamole administration resulted in higher coronary flow rate. Lower perfusate adenosine concentration was observed along with higher tissue adenosine content in this group. These results implied that coronary flow rate is determined not by interstitial adenosine concentration but by intracellular activity of adenosine. To confirm the effects of dypiridamole in vivo, direct measurement of interstitial adenosine concentration by mycrodialysis along with the assay of intracellular adenosine content was performed after intranenous dipyridamole administration. After dipyridamole infusion, intracellular adenosine content was markedly increased while interstitial adenosine concentration was not altered. In another series of experiments, the right shift of concentration-response curve of adenosine-induced vasodilation by 8-phenyltheophilline, a representative adenosine receptor antagonist, was mostly abolished by prior administration of prazosin, indicating that the influence of 8-PT on the adenosine action is not attributed to the inhibition of A2 receptor but related to the suppression of ${\alpha}-adrenoceptor$ activation. From these results, we concluded that adenosine acts intracellularly to regulate the coronary blood flow.

• Preventive Nutrition and Food Science
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• v.15 no.4
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• pp.356-359
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• 2010

Glass transition phenomena in nine Korean pure honeys (moisture content 18.3~20.1%) and honey-water mixtures by different water contents (0, 2, 5, and 10% w/w) were investigated with modulated different scanning calorimetry (MDSC). The total, reversing, and non-reversing heat flows were quantified during heating using MDSC. Glass transition was observed from reversing heat flow separated from the total heat flow. The glass transition temperatures ($T_g$) of pure honeys, which are in the range of $-42.7^{\circ}C$ to $-50.0^{\circ}C$, varied a lot with low determination coefficient ($R^2$=0.63), whereas those of honey-water mixtures decreased with a decrease in honey content. The $T_g$ values were also more significantly different among honey-water mixtures when compared to pure honeys, indicating that in the honey-water mixture system the $T_g$ values appear to be greatly dependent on moisture content. The measured heat capacity change (${\Delta}C_p$) was not influenced by moisture content.

• Korean Journal of Agricultural Science
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• v.7 no.2
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• pp.109-118
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• 1980

This test was carried out to present criterion to measure the liquid limit of weathered granite soil by using the flow-table method whose operation is easier and more convenient than slump test. The results are as follows. 1. Since liquid limit of weathered granite soil depends upon the particle size distribution, weatheredness and content of colored minerals, maximum particle size should be prescribed when the testing rule of liquid limit by flow-table method is enacted. 2. If take the averaged water content as liquid limit where the height and width of flow are 1 cm respectively by 10 times dropping, this liquid limit is slightly less than the one by slump test. The differance of liquid limit between flow table method and slump test is about 10%. 3. Correlation curves of flow width-water content and flow hight-water content show similar shapes. Those are straight lines in semi-logarithm paper just as liquid limit test. 4. This flow-table method is more convenient and has less personal error of measurement than slump test does. So flow-table method would be favourably utilized for judging the engineering properties of soil.