• Journal of Nutrition and Health
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• v.11 no.1
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• pp.33-37
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• 1978

The effect of heating time (0 to 30 hours at $180{\pm}5^{\circ}C$) on the change of flow properties, fatty acid compositions and some other characteristics such as acid value, iodine value, peroxide value and density of purified edible rice bran oil were observed. flow properties were measured with Maron-Belner type capillary viscometer. Newtonian motion was observed in non-heated oil and the oil heated for 5 hours but non-Newtonian motion was observed in the oil heated for more than 10 hours and at high shear stress. The fatty acid compositions were analyzed by gas liquid chromatography and all the components of fatty acids were reduced in amounts with extention of heating time. The acid value, peroxide value and density were increased but iodine value were decreased with extension of heating time.

• Korean Management Science Review
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• v.31 no.3
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• pp.95-111
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• 2014

It is essential to carry out an economic analysis on public water supply projects so that policy makers and water enterprises are aware of the actual value of the project. However, many popular approaches based on discounted cash flow analysis do not capture the uncertainties inherent in cash flow. In order to analyze the economic values of the water supply project of local governments, we utilize real option model, which considers uncertainty in future water price behavior and captures the value of real life flexibility. The real option model is designed to incorporate the option to expand and abandon, and it is applied to a local government case. Furthermore, we assess the project by exploring Luehrman's option space to accommodate the more efficient decision making. The results show that substantial amount of potential value is included in the public water supply service, and the overall value is greater than the value obtained from the discounted cash flow model.

• Journal of the Korean GEO-environmental Society
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• v.16 no.2
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• pp.15-25
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• 2015

As the physical and mechanical properties of lightweight air-mixed soil change in the procedure of transportation of mix truck, it is necessary to assure whether the properties during construction satisfy those in design. In this study, variations of properties of mixed soil after transportation by mix truck are proved by field test. Lightweight air-mixed soil used field test the unit weight of $9.0{\pm}1.0kN/m^3$, the flow value of $190{\pm}20mm$ was produced. To analyze variations of properties of mixed soil the unit weight and flow value of the sample before and after transport was measured unconfined compressive strength tests were performed. Mixing time was 19~175 minutes diversified. As the test results, it is known that the density, the flow value and the unconfined compressive strength of lightweight air-mixed soil change by transportation, but these values satisfy the specifications of material of air-mixed soil. After transportation the average value of the unit weight and flow value change in the flow of the $(+)0.10kN/m^3$, 4.8 mm respectively, the average change in the unit weight and the flow value due to the mixing time was constant. And unconfined compressive strength of 28-day specimen increases from 20 to $150kN/m^2$. But, these values do not have some clear relationship with the transportation time within 175 minutes which is longest test time. Consequently, Within 175 minutes the changes of properties by transportation are too small to show some problems in the construction field.

• 유체기계공업학회:학술대회논문집
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• 2002.12a
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• pp.363-369
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• 2002

Orifice meter is the most widely used flowmeter in custody transfer between KOGAS and city gas companies. Absolute pressure value is needed to calculate the gas flow of orifice metering system, but the gauge pressure transmitters are mainly used in the field. In case that the gauge pressure transmitters are used, the fixed value as standard atmospheric pressure(101.325kPa) is applied for the absolute pressure value. The real, local atmospheric pressures of each metering station are different from the standard condition as the altitude and weather conditions. In this study the flow calculation errors were quantitatively analyzed through examining the atmospheric pressures of 50 stations of KOGAS. The data for analysis are such like the time data of supplied gas amount, the altitude of each metering station, the time data of atmospheric pressures and altitudes of each weather observatory. The results showed that the local atmospheric pressures were different from the standard value and the gas flow calculation errors were distributed between $-0.024\%{\~}0.025\%$ based on the supplied gas amount in the year 1999 and 2000.

• KCID journal
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• v.14 no.2
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• pp.207-213
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• 2007

For sustainable development at a watershed, environment friendly site-specific management practices need to be developed and implemented. The soil and Water Assessment Tool(SWAT)model has been world-wide used to estimate stream flow, sediment, and nonpoint source pollutant loads, and effects on water quality of different management practices. In this study, the SWAT model was used to estimate the flow resources at Hwacheon areas using Digital Elevation Model(DEM),Land use, precipitation ,wind ,maximum and minimum temperature, solar radiation, humidity of watershed The R2 value and EI value for the comparison of SWAT estimated flow and measured flow were 0.87 and 0.67 respectively for calibration period, and the R2 value and E1 value for validation were 0.75 and 0.67 respectively. The comparison results show what the SWAT model is applicable to simulate hydrology behaviors at this study watershed.

• The Journal of Asian Finance, Economics and Business
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• v.7 no.8
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• pp.451-459
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• 2020

This study aims to examine the relationship of the four factors that increase the protection of minority shareholder investment. The factors are non-controlling shareholders, corporate governance, free cash flow, and shareholder wealth. The data for this study is obtained from the 2017 annual reports of 136 Thai public companies listed in the Market of Alternative Investment of Thailand (MAI). The analysis uses a multiple regression model to determine which factors encourage and which inhibit the protection of minority shareholder investment. The study tests four hypotheses. The results rejected H1 because non-controlling shareholders have negatively correlated with minority shareholder investment protection (beta -0.155 and p-value 0.050). The results accepted H2, H3 and H4 as follows. H2: corporate governance has positively correlated with minority shareholder investment protection (beta 0.17 and p-value 0.031). H3: free cash flow has positively correlated with minority shareholder investment protection (beta 0.214 and p-value 0.007). H4: shareholder wealth has positively correlated with minority shareholder investment protection (beta 0.318 and p-value 0.000). The major findings suggest strong minority shareholder investment protection was enhanced by increasing corporate governance, free cash flow and shareholder wealth. The protection of minority shareholder investment needs to reduce non-controlling shareholding pattern.

• Particle and aerosol research
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• v.12 no.4
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• pp.115-126
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• 2016

Numerical analysis was done to evaluate the movement of the particles and the fluid inside of the cyclone-bag hybrid dust collector. Flow discharged from the cyclone in the hybrid particle collector has swirl pattern, and it results in the biased flow to the bag filters and deteriorates the collection performance of the bag filter. The current study is to evaluate the effect of the duct lengths and the baffle arrays in the connection duct by the computational methods. Main concerns of the analysis are how to improve the uniformity of the internal flow between the cyclone and the bag filter. Numerical analysis was done to check the particle removal efficiencies of the system with respect to the flow characteristics which is expressed in RMS values of the upward flow inside of the connection duct. The flow pattern inside of the connection duct is evaluated under different the duct lengths and the baffle arrays. In case of the reference geometry the RMS value of inside flow was 56.7%, and the value was decreased to 30.1% by controlling the lengths of duct. The effects of baffle was also evaluated, the RMS value of flow could be decreased 55.2% and so on. But the pressure drop across the baffles becomes high and the system efficiency becomes lower.

• Journal of Oral Medicine and Pain
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• v.25 no.2
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• pp.145-151
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• 2000

The present study was performed to investigate the relationship between the salivary flow rate and the interpretation results of salivary scan in the patients with dry mouth. Twenty-five patients with dry mouth who visited the Dept. of Oral Medicine & Oral Diagnosis, Seoul National University Dental Hospital, were included. The unstimulated whole salivary flow rate was determined by the spitting method and the stimulated whole salivary flow rate was measured with gum-base chewing. Salivary scan was performed after the infusion of $^{99m}technetium$ pertechnetate(Tc) and interpreted. The obtained results were as follows: 1. The unstimulated and stimulated whole salivary flow rate were significantly decreased compared to normal value, which reflected the extensive destruction of salivary gland function in the patients with dry mouth. 2. The unstimulated and stimulated whole salivary flow rate were decreased in the group with decreased function in salivary scan compared with the group with normal function in salivary scan. However, there was no statistical significance between groups. 3. The difference between the stimulated and unstimulated whole salivary flow rates was greater in the group with normal function in salivary scan compared with the group with decreased function in salivary scan. 4. There was significant positive correlation between the stimulated and unstimulated whole salivary flow rates. The level of correlation was higher in the group with decreased function in salivary scan than the group with normal function in salivary scan. Collectively, these data suggested that salivary scan had the limited value. The comprehensive evaluation including history taking, clinical examination, clinical laboratory as well as the measurement of salivary flow rate are need for patients with dry mouth.

• International Journal of Fluid Machinery and Systems
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• v.4 no.4
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• pp.387-395
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• 2011

Single-blade centrifugal pumps are widely used as sewage pumps. However, the impeller of a single-blade pump is subjected to strong radial thrust during pump operation because of the geometrical axial asymmetry of the impeller. Therefore, to improve pump reliability, it is necessary to quantitatively understand radial thrust and elucidate the behavior and mechanism of thrust generating. This study investigates the radial thrust acting up on a single-blade centrifugal impeller by conducting experiments and CFD analysis. The results show that the fluctuating component of radial thrust increases as the flow rate deviates from the design flow rate to low or high value. Radial thrust was modeled by a combination of three components, inertia, momentum, and pressure by applying an unsteady conservation of momentum to the impeller. The sum of these components agrees with the radial thrust calculated by integrating the pressure and the shearing stress on the impeller surface. The behavior of each component was shown, and the effects of each component on radial thrust were clarified. The pressure component has the greatest effect on the time-averaged value and the fluctuating component of radial thrust. The time-averaged value of the inertia component is nearly 0, irrespective of the change in the flow rate. However, its fluctuating component has a magnitude nearly comparable with the pressure component at a low flow rate and slightly decreased with the increase in flow rate.

• Journal of Environmental Science International
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• v.24 no.4
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• pp.359-369
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• 2015

This study analyzed the velocimetry of runoff and measured the flood discharge by applying the SIV (Surface Image Velocimetrer) to the daytime and nighttime flow image data with special reference to Seong-eup Bridge at Cheonmi stream of Jeju during the flow by the severe rainstorm on May 27, 2013. A 1000W lighting apparatus with more than 150 lux was installed in order to collect proper nighttime flow image applied to the SIV. Its value was compared and analyzed with the velocity value of the fixed electromagnetic wave surface velocimetry (Kalesto) at the same point to check the accuracy and applicability of the measured velocity of flow. As a result, determination coefficient $R^2$ values were 0.891 and 0.848 respectively in line with the velocity distribution of the daytime and nighttime image and the flow volume measured with Kalesto was approximately 18.2% larger than the value measured with the SIV.