• Bulletin of the Korean Chemical Society
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• v.21 no.5
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• pp.503-509
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• 2000

The solvent effects on the relative free energies of solvation and the difference in partition coefficients (log P) for $Rb^+$ to $K^+$ mutation in several solvents have been investigated using Monte Carlo simulation (MCS) of statistical perturbation theory(SPT). In comparing the relative free energies for interconversion of one ion pair, $Rb^+$ to $K^+$, in $H_2O$(TIP4P) in this study with the relative free energies of the computer simulations and the experimental, we found that the figure in this study with the relative free energies of the computert simulations and the experimental, we found that the figure in this study is $-5.00\pm0.11$ kcal/mol and those of the computer simulations are $-5.40\pm1.9$, -5.5, and -5.4 kcal/mol. The experimental is -5.1 kcal/mol. There is good agreement among various studies, taking into account both methods used to obtain the hydration free energies and standard deviations. There is also good agreement between the calculated structural properties of this study and the simulations, ab initio and the experimental results. We have explained the deviation of the relationship between the free energy difference and the Onsager dielectric function of solvents by the electron pair donor properties of the solvents. For the $Rb^+$ and $K^+$ ion pair, the Onsager dielectric function of solvents (or solvent permittivity), donor number of solvent and the differences in solvation dominate the differences in the relative free energies of solvation and partition coefficients.

• International Journal of Air-Conditioning and Refrigeration
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• v.12 no.4
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• pp.198-205
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• 2004

An experimental study was carried on the characteristics of fluid flow and heat transfer in a fluidized bed shell-and-tube type heat exchanger with corrugated tubes. Seven different solid particles having same volume were circulated in the tubes. The effects of vari­ous parameters such as water flow rates, particle geometries and materials, and geometries of corrugated tubes on relative velocities and drag coefficients were investigated. The present work showed that the drag force coefficients of particles in the corrugated tubes were usually lower than those in the smooth tubes, meanwhile the relative velocities between particles and water in the corrugated tubes were little higher than those in the smooth tubes except the particles of glasses.

• Journal of Astronomy and Space Sciences
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• v.35 no.1
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• pp.1-6
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• 2018

The reanalysis of the previously published abundance pattern of mild barium star HD202109 (${\zeta}$ Cyg) and the chemical compositions of 129 thin disk barium stars facilitated the search for possible correlations of different stellar parameters with second ionization potentials of chemical elements. Results show that three valuable correlations exist in the atmospheres of barium stars. The first is the relationship between relative abundances and second ionization potentials. The second is the age dependence of mean correlation coefficients of relative abundances vs. second ionization potentials, and the third one is the changes in correlation coefficients of relative abundances vs. second ionization potentials as a function of stellar spatial velocities and overabundances of s-process elements. These findings demonstrate the possibility of hydrogen and helium accretion from the interstellar medium on the atmospheres of barium stars.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.15 no.5
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• pp.406-412
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• 2003

An experimental study was carried on the characteristics of fluid flow and heat transfer in a fluidized bed shell-and-tube type heat exchanger with corrugated tubes. Seven different solid particles having same volume were circulated in the tubes. The effects of various parameters such as water flow rates, particle geometries and materials, and geometries of corrugated tubes on relative velocities and drag coefficients were investigated. The present work showed that the drag force coefficients of particles in the corrugated tubes were usually lower than those in the smooth tubes, meanwhile the relative velocities between particles and water in the corrugated tubes were little higher than those in the smooth tubes except the glass.

• Journal of Distribution Science
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• v.13 no.8
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• pp.81-90
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• 2015

Purpose - To vitalize a market or develop a new one, companies frequently release new products into the market, often by shortening the time to market, called the release period. This research aims to investigate the purchase intention behavior of consumers in terms of buying new products at the time of product release based on the release speed. Research Design, Data, and Methodology - The research reviews the influence of relative advantage, complexity, and compatibility among innovative attributes of new products, as proposed by Rogers. Moreover, it examines the moderating effect of the innovative new product attributes in terms of speed of obsolescence of old products and how that influences consumer purchase behavior. Additionally, this study tests the research hypotheses using empirical analysis. Results - The analysis demonstrated that the relative predominance (H1) and suitability (H3) of new products had a statistically significant positive influence on new product purchase intention. However, the complexity (H2) of new products had a statistically significant positive influence on new product purchase intention in contrast to its predicted sign (-). The results of the moderating effect of the old product use period were as follows. H4-1 was not supported since the difference between the path coefficients of the group with the low level old product use period and the group with the high level, represented by the relationship of relative predominance and new product purchase intention, was not statistically significant. H5-1 was also not supported since the difference between the path coefficients of the group with the low level of old product use period and the group with the high level, represented by the relationship of complexity and new product purchase intention, was not statistically significant. However, H4-2 was supported since the difference between the path coefficients of the group with the low level of old product use frequency and the group with the high level, represented by the relationship of relative advantage and new product purchase intention was statistically significant. H5-2 was not supported since the difference between the path coefficients of the group with the low level of old product use frequency and the group with the high level, represented by the relationship of complexity and new product purchase intention, was not statistically significant. H6-2 was also not supported since the difference between the path coefficients of the group with the low level of old product use frequency and the group with the high level, represented by the relationship of compatibility and new product purchase intention, was not statistically significant. Conclusion - According to the results, only H4-2 among the hypotheses on the moderating effect of the old product use period and use frequency was statistically significant. Future research should focus on carrying out a detailed review of the hypothesis on the moderating effect of the old product usage period and frequency, find the cause, and connect this to potential new research.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2000.05a
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• pp.26-33
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• 2000

This study was conducted to investigate the relationships between yearly variations of elimatic elements and yearly variations of productivity in potato. In addition, correlation coefficients among yield and yield components were estimated. The data of yield and yield components were investigated for 9 years from 1987 to 1995. The meteorological data what gathered at the Goheung Weather Station for the same period of crop growing season were used to find out the relationships between climatic elements and crop productivity. Yearly variation of the daily minimum temperature in March and April were large with coefficients of variation (C.V.) of 126.0%, 368%, respectively, but the variation of the daily mean and maximum temperature in May and June were relative small. Stem length and number of stem show more C.V. of 9.3%, 14.3%, respectively, but the variation of the yield was relative small with 3.7%. Correlation coefficients between the amount of precipitation in April and yield, yield and daily mean temperature in June were negatively significant at the level of 5, 1 %, respectively. Correlation coefficients between the growth habits and yield are positively significant at the level of 5, 1 %, respectively. Simple linear regression equations by the least square method are estimated for stem length (Yl) and the precipitation in April(X) as Y,=82.47-0.11x (R2=0.3959), and for yield(Y2) and the precipitation in April(X) as Y,=2003.61-0.94X (R2=0.5418).

• Animal cells and systems
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• v.14 no.4
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• pp.291-296
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• 2010

Population ecological characteristics of growth and mortality play an important role in understanding the population dynamics of marine mammals. The instantaneous coefficients of natural and bycatch mortality were estimated for minke whales (Balaenoptera acutorostrata) in Korean waters using a population assessment model composed of bycatch and abundance data. The survivorship curve of this population was fitted to the data, and then the curve was revised using age-specific relative bycatchability coefficients ($q_t$). Instantaneous coefficients of natural and bycatch mortality of minke whales were estimated as 0.024/year and 0.076/year, respectively, and from this the survival rate was estimated as 0.905. This estimated survival rate was comparable to other cetaceans in other regions. The $q_t$ for this population ranged from 0.020 to 0.193. The revised survival rates were higher when the $q_t$ was taken into account. The mortality coefficient, survival rate, $q_t$ and survivorship curves had not previously been determined for minke whale in this area. This estimate could serve as fundamental information to assess the status of this population and for conservation and rational management.

• Journal of the Korean Institute of Telematics and Electronics D
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• v.34D no.7
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• pp.1-7
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• 1997

The physical optical solution to the E-polarized diffraction by a composite wedge consisting of perfect conductor and lossless dielectric cannot sayisfy not only the boundary conditions at the wedge interfaces but also the edge condition at the wedge tip. Its diffraction coefficients are extended outside the composite wedge to become the exact solution to the perfectly conducting wedge as its relative dielectric constant increases to infinite or decreases to 1. It is assured that the extended diffraction coefficients approach zero in the arificially complementary region of the composite wedge.

• Tribology and Lubricants
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• v.14 no.1
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• pp.14-22
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• 1998

This paper describes the effects of exciting frequency on the stiffness and damping coefticients of a 5-pad tilting pad journal bearing, LOP (load on pad) type. The stiffness and damping coefficients are investigated experimentally under the different values of exciting frequency, bearing load and shaft speed. These coefficients are estimated by measuring the response of the relative displacement between the bearing and the shaft and acceleration of the bearing due to the known exciting loads acting on the bearing. In order to analysis the response of exciting load, displacement and acceleration, a FFT analyzer is used. It is shown that the variation of exciting frequency has a little effect on both the stiffness and damping coefficients. Both the stiffness and damping coefficients in the loading direction are decreased by the increase of shaft speed but increased by the increase of bearing load.

• Nuclear Engineering and Technology
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• v.29 no.4
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• pp.291-298
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• 1997

In advanced nuclear reactors, the passive containment cooling has been suggested to enhance the safety. The passive cooling has two mechanisms, air natural convection and oater cooling with evaporation. To confirm the coolability of PCCS, many works have been performed experimentally and numerically. In this study, the water cooling test was performed to obtain the evaporative heat transfer coefficients in a scaled don segment type PCCS facility which have same configuration with AP600 prototype containment. Air-steam mixture temperature and velocity, relative humidity and well heat flux are measured. The local steam mass flow rates through the vertical plate part of the facility are calculated from the measured data to obtain evaporative heat transfer coefficients. The measured evaporative heat transfer coefficients are compared with an analytical model which use a mass transfer coefficients. From the comparison, the predicted coefficients show good agreement with experimental data however, some discrepancies exist when the effect of wave motion is not considered. Finally, a new correlation on evaporative heat transfer coefficients are developed using the experimental values.