• Journal of the Korean Society of Visualization
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• v.15 no.2
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• pp.16-20
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• 2017

A coffee-ring effect is from capillary flow by different evaporation rate across the droplet. The capillary flow tends particles to accumulate at the edges of the droplet and makes the ring-shaped stain pattern. These coffee-ring formation and suppression of coffee-ring have been a critical role in printing and coating technologies. In this study, we present the experimental study on coffee-ring effect of silver nanowire inside the evaporating sessile droplet. Size and concentration effect of nanowires at coffee-ring effect has been investigated. From the coffee-ring, we observed the regimes of connected rings and disconnected ones and measure the resistivity of single ring pattern with different nanowire length.

• International Journal of Vascular Biomedical Engineering
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• v.1 no.2
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• pp.4-12
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• 2003

The present study investigated the effect of transverse vibration on the hemorheological characteristics of blood using a newly designed pressure-scanning capillary viscometer. As vibration was applied, aggregated blood cells (rouleaux) were disaggregated. The range of vibration frequency and amplitude are $0{\sim}100\;Hz$ and $0{\sim}0.8\;mm$, respectively for a capillary diameter 0.84 mm. As vibration increased, blood viscosity initially increased and tended to decrease. In order to delineate the unexpected results, the present study proposed two counteracting mechanisms of vibration related with red blood cell (RBC) aggregation affecting hemo-rheological properties. One is the reduction of RBC aggregation due to vibration causing an increase of blood viscosity. The other is forced cell migration due to the transverse vibration, which in turn forms a cell-free layer near the tube wall and causes a decrease of flow resistance.

• Journal of the Korean Ceramic Society
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• v.36 no.9
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• pp.991-996
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• 1999

Effect of solution property on the weight varation and microstructural change of film was studied by electrophoretic deposition in order to obtain a homogeneous and dense zirconia film. As a result of weight kinetics of film which obtained in alcohol or aqueous solution having different polarity experimental data showed large deviation from theoretical ones calculated by Zhang's kinetic model. It had been shown that the weight affecting factors was largely dependent on properties other than dielectric constant and viscosity of solvent zeta potential appiled field and time. In initial stage a main factor of the drastic weight increase was the capillary drag of porous substrate. The cause of weight decrease with time in aqueous solution after 300 s was attributed to the defect of film by sagging and electrolytic reaction. The electrolyte film which prepared in alcohol solution with good wetting for substrate had better homogeneous and dense microstructure than one in aqueous solution with high surface tension.

• Journal of the Korean Society of Food Science and Nutrition
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• v.30 no.3
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• pp.450-454
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• 2001

The physical properties of ramyon made of potato starch at various levels (12, 14 16%) were investigated to find out the effect of potato starch on ramyon quality. The higher starch content in dough, the higher water content after steaming and the lower moisture content after deep frying. As the starch content increased, the magnitudes of extrusion work of cooked ramyon and capillary viscosity of ramyon soup increased but the starting temperature of gelatinization decreased. There was a good correlation ($R^2$=0.99) between extrusion work and capillary viscosity. Firmness and chewiness values measured by texture analyser decreased with increase in starch content while tenderness and overall texture preference evaluated by sensory analysis increased.

• Journal of Haehwa Medicine
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• v.19 no.2
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• pp.173-177
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• 2011

We treated a 45 year-old male patient. He had Hypertension, Diabetes, Hyperlipidemia and Obesity. The main symptoms were Low-back pain, General body weakness, Abdominal discomfort. We diagnosed him as metabolic syndrome and prescribe Yagwanchunghyul-tang three times a day. We observed clinical symptoms Blood pressure, Capillary blood glucose, BMI, Body weight. Cholesterol, Triglyceride. After the treatment, The main symptom, blood pressure, capillary blood glucose(PP2hr), Hypercholesterol, Hypertriglyceride were improved. and BMI levels fell. This case shows that Yagwanchunghyul-tang has an effect on Metabolic syndrome like a Hypertension, Diabetes, Hyperlipidermia, Hypertriglyceride.

• Journal of the Korean Ceramic Society
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• v.22 no.5
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• pp.23-28
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• 1985

A model for degradation of $eta$-$Al_2O_3$ is derived from sress generated by Poiseuille pressure capillary effect and effulent flux in charging process of Na-S Battery. Critical current density for degradation increase with increasing the crack length and crack tip radius. radius 10-7cm and crack length 10-5cm Dependence of crack growth velocity on crack lengh is seperated two regions that is for a large crack length it is predominated by Poiseuille pressure and effulent fluex but in the case of small crack length it is controlled by capillary effect.

• Journal of the Korean Wood Science and Technology
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• v.25 no.3
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• pp.66-74
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• 1997

Liquid permeabilities of red oak and several softwoods were measured by the pressure bomb method and a modified liquid permeability method in order to investigate their efficacy. The effect of preboiling and prefreezing on wood permeability were also examined for both green and resaturated specimens. Regardless of some disadvantages these two methods were revealed as a handy tool for quick evaluation of the permeability of an unknown species. The permeabilities of the resaturated specimens increased when preboiled. but decreased when prefrozen. For green specimens, however, pre freezing increased permeability. The discrepancy of the pre freezing effect on two specimens partially attributes to their difference of initial permeabilities. For all species except radiata pine heartwood, the radii of the effective capillary pores, derived from the water potential equation, distribute from $0.42{\mu}m$ to $7.2{\mu}m$. Those of radiata pine heartwood are below $0.46{\mu}m$.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.37 no.2 s.110
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• pp.11-20
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• 2005

This study was carried out to investigate the influence of paper stock type and heat treatment on sizing effect. Various types of pulps were used to make handsheets sized internally with AKD(alkyl ketene dimer) and externally with CMC(carboxyl methyl cellulose). Most of the handsheets were treated with heat by dry oven $(100^{\circ}C,\;30min)$ to evaluate the effect of heat treatment on sizing development. Internal sizing development of newsprint was very bad, but the effect of heat treatment was much higher than those of NBKP, BCTMP. In case of surface sizing, newsprint was more effective compared to the other pulps. Considering above mentioned results, it seems that internal sizing slows down water into paper by molecular diffusion much more than capillary penetration, but surface sizing slows down capillary penetration. With regard to density, a higher thickness sheets showed high heat treatment effect on sizing, therefore it assumed that heat treatment effect on sizing had very close relationship with sheet density.

• Journal of Advanced Marine Engineering and Technology
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• v.37 no.4
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• pp.351-357
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• 2013

In flip chip packaging, underfill process is used to fill epoxy bonder into the gap between a chip and a substrate in order to improve the reliability of electronic devices. Underfill process by capillary motion can give rise to unwanted air void formations since the arrangement of solder bumps affects the interfacial dynamics of flow meniscus. In this paper, the unsteady flows in the capillary underfill process are visualized and then the racing effect and merging of the meniscus are investigated according to the arrangement of solder bumps. The result is shown that at higher bump density, the fluid flow perpendicular to the main direction of flow becomes stronger so that more air voids are formed. This phenomenon is more conspicuous at a staggered bump array than at a rectangular bump array.

• Journal of the Korean Wood Science and Technology
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• v.46 no.6
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• pp.681-691
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• 2018

The typical methods of mercury intrusion porosimetry (MIP) and capillary flow porometry (CFP) were used to evaluate the pore size of cross-section of wood and the effect of the pore structure on the permeability of wood was analyzed in this study. The results of this study were as followings: The pore size of wood measured by CFP was larger than that measured by MIP except for Lime tree, Korean red pine and Paulownia. Among the three pore types of porous materials defined by IUPAC (through pores, blind pores, and closed pores), only through pores are related to permit fluid flow. MIP measures the pore size of both through pores and blind pores, while CFP measures the pore size of only constricted through pores. Therefore, pore size measured by MIP was not related to gas permeability, however pore size measured by CFP had a proportional relationship with gas permeability.