• Journal of the Korean Society of Tobacco Science
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• v.13 no.1
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• pp.13-18
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• 1991

This experiment carried out to review influence of relative humidity, temperature and net weight on cigarette hardness for the uniformal control of cigarette quality. Obtained results are as follows: 1. The difference in the cigarette physical properties of constant hardness control is considerably lower than that of constant net weight control. 2. Contribution rate for cigarette hardness is relative humidity > net weight > temperature. 3. The multiple regression equation of cigarette hardness related with relative humidity, temperature and net weight is calculated as follows.

• English Language & Literature Teaching
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• v.9 no.1
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• pp.173-187
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• 2003

This paper proposes a semantic description of the English nominal relatives with a knowledge representation framework of Conceptual Graphs(CGs), which is a computer-oriented form of interlanguage from the Conceptual Structures Theory. This paper focuses on the difference between definite and universally quantified meaning of nominal relatives, on the compound relative clauses, and also on the difference between nominal relative clauses and interrogative clauses.

• Progress in Medical Physics
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• v.28 no.3
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• pp.111-121
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• 2017

Verification of dose distribution is an essential part of ensuring the treatment planning system's (TPS) calculated dose will achieve the desired outcome in radiation therapy. Each measurement have uncertainty associated with it. It is desirable to reduce the measurement uncertainty. A best approach is to reduce the uncertainty associated with each step of the process to keep the total uncertainty under acceptable limits. Point dose patient specific quality assurance (QA) is recommended by American Association of Medical Physicists (AAPM) and European Society for Radiotherapy and Oncology (ESTRO) for all the complex radiation therapy treatment techniques. Relative and absolute point dose measurement methods are used to verify the TPS computed dose. Relative and absolute point dose measurement techniques have a number of steps to measure the point dose which includes chamber cross calibration, electrometer reading, chamber calibration coefficient, beam quality correction factor, reference conditions, influences quantities, machine stability, nominal calibration factor (for relative method) and absolute dose calibration of machine. Keeping these parameters in mind, the estimated relative percentage uncertainty associated with the absolute point dose measurement is 2.1% (k=1). On the other hand, the relative percentage uncertainty associated with the relative point dose verification method is estimated to 1.0% (k=1). To compare both point dose measurement methods, 13 head and neck (H&N) IMRT patients were selected. A point dose for each patient was measured with both methods. The average percentage difference between TPS computed dose and measured absolute relative point dose was 1.4% and 1% respectively. The results of this comparative study show that while choosing the relative or absolute point dose measurement technique, both techniques can produce similar results for H&N IMRT treatment plans. There is no statistically significant difference between both point dose verification methods based upon the t-test for comparing two means.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.2 no.2
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• pp.137-141
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• 1990

When the relative humidity is measured with an aspirated psychrometer, three factors, which affect the measurement of relative humidity, are atmospheric pressure, the size of wet element and the wind velocity. This paper investigated the effects of the above three factors, and the computer code was developed in order to enhance the accuracy of the relative humidity measurement. As results, it is found that the relative humidity decreases by 6%RH with increasing atmospheric pressure from 650 mbar to 1100 mbar. It is found that the relative humidity drops down when the size of the wet element increases, though the effect of the size of the wet element is not significant. Finally, relative humidity increases with the increasing wind velocity. The difference between the psychrometic table in the present KS and the present results is about 2%RH maximum. As a conclusion, the three factors mentioned above should be considered in order to secure accurate measurement of relative humidity.

• The Korean Journal of Ecology
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• v.19 no.2
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• pp.165-178
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• 1996

We investigated the role of competition in adaptation to varying water availability levels for two ecotypically-differentiated populations of Impatiens pallida found naturally in low- vs. high-water environments. In a greenhouse experiment, seedlings were grown in pure cultures at two densities (n=1 and 2 plants per pot) and in mixed cultures (n=2) under low-, medium- and high-water treatments. The two populations were shown to be genetically distinct across the range of environmental conditions in the greenhouse experiment, confirming previous findings. The two populations had similar morphological responses to density and water availability in pure cultures and mixtures, but the population from the high-water environment showed a greater growth response to high water availability than did the population from the low-water environment and the difference in growth between the two populations decreased from the high-water to low-water treatment. Relative competitive ability of two populations were compared under three different water treatments and two densities. Differential response to watering treatment and density were not reflected in a difference in relative competitive ability. Relative yield totals were significantly greater than 1 overall. The niche differentiation suggested by RYTs>1 may be responsible for the lack of differential competitive effects observed for populations in the three vatering treatments.

• 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.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2012.11a
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• pp.71-72
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• 2012

The purpose of this study is to evaluate the depth of carbonation considering the relative humidity in concrete using the FEM model. The difference of relative humidity in concrete has not been considered in calculating the carbonation depth in analytic model. That reason can make the over estimation in expectation of RC structure durability. The temperature and R.H. expectation model and the carbonation depth expectation model are development in past author's studies. The two models are coupled in this study. The fact that there is the difference between actual environment and acceleration test is revealed from FEM numerical analysis.

• Knowledge Management Research
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• v.15 no.2
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• pp.147-164
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• 2014

This paper investigated the efficiency of automobile firms by using several non-parametric approaches. First, using Data Envelopment Analysis (DEA), the paper has investigated the critical factors that determine the relative efficiency of management performance in automobile companies. Second, we examined how the firm size impact on the difference of this efficiency by using Kruskl-Wallis Test. Third, by using Mann-whitney test, we also investigated the difference of the efficiency accoss existence of technological innovation activity. Finally, the paper explored the relationship between technological innovation and management efficiency by using logistic regression model. The findings of this study provided practical information for inefficient automobile firms to find benchmarking firms and strategic position to improve their efficiency. The result also provided theoretical and methodological implications for those who explore factors affecting management efficiencies. Future research directions with the limitation of the study are discussed.

• Structural Engineering and Mechanics
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• v.13 no.4
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• pp.355-368
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• 2002

In this paper, we address the numerical investigation on the effect of liquid compressibility onto the natural frequency of liquid-filled containers. Traditionally the liquid motion has been treated as an ideal fluid motion. However, from the numerical experiments for the axisymmetrical free-vibration of cylindrical liquid-storage tanks, we found that the relative difference in natural frequencies between ideal and compressible motions becomes remarkable, as the slenderness of tank or the relative liquid-fill height becomes larger. Therefore, in such cases of dynamic systems, the liquid compressibility becomes an important parameter, for the accurate vibration analysis. For the free-vibration analysis of compressible liquid-structure interaction we employed the coupled finite element formulation expressed in terms of the acoustic wave pressure and the structure deformation.

• Journal of Korean Ophthalmic Optics Society
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• v.20 no.2
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• pp.177-186
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• 2015

Purpose: The Purpose of this study is to investigate if the relative legibility of optotypes affects the corrected visual acuity in visual acuity test. Methods: After measuring the relative legibility of 'Landolt ring target', 'arabic number target', 'alphabet target' by showing as a single-letter-target in 24 subjects without specific ocular diseases and ocular surgery experience, the relative legibility of 0.8, 1.0, 1.25 row of vision according to type of target in 7 types of chart were compared. After then we compared by measuring the corrected visual acuity according to type of target by using binocular MPMVA test (#7A) in 60 myopic subjects. Results: In 3 types of target the worst relative legibility target was 'Landolt ring target' with legible distance of $98.97{\pm}4.57cm$ and the best relative legibility target was 'alphabet target' with legible distance of $108.42{\pm}3.46cm$. There was no difference of the relative legibility according to type of chart or visual acuity level in the row of vision if other conditions are the same. In 1.0 and 1.25 row of vision the difference of relative legibility according to type of target was shown the statistically significant difference between 'Landolt ring target' and 'alphabet target' as $-0.07{\pm}0.06$ (p=0.02) and $-0.06{\pm}0.06$ (p=0.04) respectively. In myopia the difference of corrected visual acuity according to type of target was statistically significant difference between 'Landolt ring target' and 'arabic number target' as $-0.04{\pm}0.02$ (p=0.02) and it was especially remarkable in the low myopia. Conclusions: Measuring visual acuity with different optotypes could cause the errors in best vision measurement value because there was difference of the relative legibility according to type of target even though visual acuity level is same in the row of vision.