• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2003.09a
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• pp.132-135
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• 2003

Solution chemistry, sorbate chemistry, and sorbent chemistry were widely investigated to find important factors that affect PAH sorption on mineral surfaces and to elucidate its microscopic mechanism. The solution chemistry, pH and ionic strength caused measurable change of HOC sorption reaction to minerals. The detectable change of Ka occurred at a pH region crossing the PZC (Point of Zero Charge) of each mineral. The PAH hydrophobicity, one of sorbate chemistry, was observed to have a strong correlation with PAM sorption to mineral. Mineral surface area was not found to be a predominant factor controlling PAH sorption. The mineral type might be more likely to play a crucial role in controlling the PAH sorption behavior. The CEC (Cation Exchange Capacity) of mineral, representing surface charge density, has meaningful correlation with regression slope of sorption coefficients (log $K_{d}$) versus aqueous activity coefficients (log Υ$_{w}$).).).

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2005.04a
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• pp.6-8
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• 2005

The forest soils of 92 sites in Korea were analyzed to survey heavy metal background levels using aqua regia digestion method and 0.1N HCl extraction method. From these results, the average natural contents of heavy metals were Cd 0.287, Cu 15.26, Pb 18.43, Cr 25.36, Zn 54.27, Ni 17.68mg/kg for aqua regia method, and Cd 0.040, Cu 0.48, Pb 3.06, Cr 0.09, Zn 1.54, Ni 0.27mg/kg for 0.1N HCl extraction method. The range of correlation coefficients between heavy metal contents obtained from two methods(aqua regia and 0.1N HCl) was significant as $0.24{\sim}0.88$, and the correlation coefficients were decreased in order of Cd, Pb, Cu, Ni, Cr, Zn.

• Journal of the Korean Home Economics Association
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• v.24 no.3
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• pp.1-9
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• 1986

The purpose of this study was to measure the body cathexis and clothing satisfaction sccording to the level of age, job, and total monthly income and to investigate the relationship between body cathexis and clothing satisfaction of married women. 43 items of body parts and body functions were selected to measure body cathexis from Secord and jourard body Cathexis scale. A nd 56 items of Mclean's Clothing Satisfac tion scale were used for clothing satisfaction. The questionnaires were administered to 384 mothers in Jeonbug province. 3-way ANOVA and Newman-Keuls test were used for group difference. Pearson's Correlation Coefficients, Partial Correlation Coefficients, Standard Deviation, and Mean were calculated. RESULTS : 1. Body cathexis of married women showed asignificant difference according to age. 2. Clothing satisfaction of married women showed a significant difference to the interaction of age, job, and total monthly income. The elder and higher income group without job had the highest clothing satisfaction scores than any other group. 3. Positive correlations were found among body cathexis, clothing satisfaction, and 6 subscales of clothing satisfaction.

• 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.

• Wind and Structures
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• v.16 no.5
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• pp.491-515
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• 2013

Wind pressure characteristics on a double tower high-rise structure, which is disturbed by surrounding buildings, were investigated using large eddy simulation (LES) and 1:300 scale wind tunnel experiments. The computational simulation technique and wind tunnel experimental technique were described in detail initially. Comparisons of computational results with the experimental data have subsequently been carried out to validate the reliability of LES. Comparisons have been performed in detail for the mean and fluctuating pressure coefficients. Detailed explanations of each comparison were given in the paper. To study further on the pressure coefficients on the building surfaces, parametric studies on shape coefficient and spatial correlation were performed and investigated. The numerical and experimental results presented in this paper advance understanding on wind field around buildings and the application of LES and wind tunnel tests.

• Journal of the Society of Naval Architects of Korea
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• v.43 no.1 s.145
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• pp.50-58
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• 2006

Free running model tests gives us only maneuvering indices not hydrodynamic derivatives. For this reason, system identification method has been applied to the measured data to identify mathematical model describing hydrodynamic force. However It is difficult to obtain complete set of maneuvering derivatives because of strong correlation of sway velocity and yaw rate. Therefore, in this paper, we assumed that sway velocity related coefficients would be obtained by oblique towing test. and then proposed new procedure to estimate yaw related coefficients. To do this, correlation and regression analyses were carried out to establish modified model and estimate maneuvering derivatives. Also D-optimal rudder input scenario was found based on the modified model and confirmed the validity of its sufficient richness as a input scenario.

• Proceedings of the KSRS Conference
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• 1999.11a
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• pp.425-428
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• 1999

The radar interferogram represents phase differences between the two synthetic aperture radar observations acquired in slightly different angle. The success of the radar interferometric application largely depends on the quality of the interferogram generated from two or more synthetic aperture radar data sets. We propose here to apply the wavenumber correlation analysis to the in-phase and quadrature phase of the radar interferogram. The wavenumber correlation analysis is to resolve the highly correlated components from the low correlation components by estimating correlation coefficients for each wavenumber component. Through this approach, one can easily distinguish the signal components from the noise components in the wavenumber domain. Therefore, the wavenumber correlation analysis of the radar interferogram can be utilized to design post filter and to estimate the quality of interferogram. We have tested the wavenumber correlation analysis using a Radarsat SAR data pair to demonstrated the effectiveness of

• Journal of Nutrition and Health
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• v.33 no.2
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• pp.202-215
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• 2000

Intake frequency of one food is often associated with other food items, but few studies examined the relationship of food intake frequency among food items. Finding the relationship among intake frequencies of different food might be useful to understand the food intake patterns of population and correlated foods would be used as an indicators of another food intake. Relationship of food intake can be also applied to make a more simple and useful form of food frequency questionnaire to assess the association between diet and various diseases. The objective of this study was to examine the correlation of intake frequency among food items in food frequency questionnaire (FFQ). A FFQ with 84 food items was administered to 14533 Korean males who 40-65 years of age participating Korean cancer research survey. Data fromm 7647 subjects who completed FFQ were used to examine correlation among food items with three different methods-log linear regression models, Spearman correlation coefficients and cell frequency distribution. To examine the rank correlation, coefficients were calculated by Spearman correlation after scoring the frequency categories. Three most correlated foods were selected in every food intems by three methods each. In most food items, there was positive correlatin, except cooked rice and cooked brown rice, in intake frequency between foods that belonged to similar food groups. But serveral food items-Sausage (processed fish, cheese), Milk (whilte bread, orange juice), Soymilk(other juices), Cheese (pizza, butter), and Coffee(thick beef soup)-showed correlation among totally different food groups. Two sets of food items which were selected by log linear regression model and Sperman correlation coefficients were compared. There were exactly three common foods in 18 food items, 2 common foods in 47 items, 1 common food in 16 items and no common food in 3 items among 3 ranked foods. Three sets of selected food were compared. There were exactly three common foods in 5 food items, 2 common foods in 21 items, 1 common food in 34items and no common food in 24 items among 3 ranked foods. These results indicate that certain patterns exist among intake frequencies of specific food items in the FFQ. More researches are suggested to understand the relationshiops among the intakes of foods so that this information can be used in developing better FFQ or analyzing missing items from self-administered FFQ.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.21 no.7
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• pp.1276-1284
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• 2017

Lightweight Encryption Algorithm (LEA) that was standardized as a lightweight block cipher was implemented with 8-bit data path, and the vulnerability of LEA encryption processor to correlation power analysis (CPA) attack was analyzed. The CPA used in this paper detects correct round keys by analyzing correlation coefficient between the Hamming distance of the computed data by applying hypothesized keys and the power dissipated in LEA crypto-processor. As a result of CPA attack, correct round keys were detected, which have maximum correlation coefficients of 0.6937, 0.5507, and this experimental result shows that block cipher LEA is vulnerable to power analysis attacks. A masking method based on TRNG was proposed as a countermeasure to CPA attack. By applying masking method that adds random values obtained from TRNG to the intermediate data of encryption, incorrect round keys having maximum correlation coefficients of 0.1293, 0.1190 were analyzed. It means that the proposed masking method is an effective countermeasure to CPA attack.

• Journal of Korea Water Resources Association
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• v.49 no.3
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• pp.207-215
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• 2016

In this study, it is analyzed how large scale climate variation has an effect on climate systems over Korea using correlation analysis between climate indices and Intrinsic Mode Functions (IMFs) of precipitation and temperature. For this purpose, the estimated IMFs of precipitation and temperature from the accompanying paper were used. Furthermore, cross correlation coefficients and lag time between climate indices and IMFs were calculated considering periodicities and tendencies. As results, more accurate correlation coefficients were obtained compared with those between climate indices and raw precipitation and temperature data. We found that the Korean climate is closely related with climate variations of $El-Ni{\tilde{n}}o$ in terms of periodicity and its tendency is followed with increasing sea surface temperature due to climate change.