• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.17 no.12
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• pp.1185-1191
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• 2005

Published correlation equations of the enthalpy of vaporization are reviewed and a new four-parameter correlation equation is proposed. Performance of the proposed equation is examined using the ASHRAE data for 22 pure substance refrigerants as reference data. The new equation yields an average absolute deviation of $0.05\%$, which is smaller than those of published equations, such as equations of Guermouche-Vergnaund $(0.08\%)$, Aerebrot $(0.13\%)$, Radoz-Lydersen $(0.08\%)$, and Somayajulu $(0.08\%)$. The three adjustable parameters of the modified correlation are optimized and reported for 22 substances. The equation proposed in this work is valid over the entire temperature range where data points exist.

• Economic and Environmental Geology
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• v.17 no.4
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• pp.289-298
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• 1984

Uraniferous black slates of the Okchon sequence occur in Koesan (northeast) through Miwon-Boun (middle) to the southwest off Taejon (southwest) within the Okchon fold belt. The Uraniferous balck slates in the southwest off Taejon are particularly well developed in Chubu (northeast) and Moksso-ri (middle) areas whereas they are less developed in Jinsan (southwest) area. The uraniferous beds range from less than a meter to 40 meters in thickness and range from less than 0.02% $U_3O_8$ (cut-off-grade) to 0.05% $U_3O_8$ in the southwestern district off Taejon. Electron microprobe analysis of uranium-minerals found in graphitic slate samples enables to estimate their major compositions semi-quantitatively so that uraninite, ferro-uranophane and chlopinite are tentatively identified. Uranium-minerals are closely associated with carbon and metal sulfides. Correlation analysis of trace element concentrations revealed that U and F.C., and U and Mo are lineary correlative respectively and their correlation coefficients are positively high whereas those of U and V, U and Mn, and U and Zr are negatively low, implying that uranium mineralization has been closely related with concentrations of carbon and molybdenum. Stable isotope analyses of pyrite sulfur range widely from +11.5% to -23.3% in ${\delta}^{34}S$ values whereas those of graphite carbon fall within a narrow range between -23.3% and -28.9% in ${\delta}^{13}C$ values. The wide range of ${\delta}^{34}S$ values suggests that the sulfur could be of meteoric origin rather than of igneous source. The narrow range of ${\delta}^{13}C$ values, which are close to those of coal, indicates that the graphite is organic carbon in origin. Therefore, it is concluded that the uranium mineralization in the Okchon sequence took place primarily in sedimentary environment rich in organic matter and sulfide ion, both of which served as the reducing agents to convert soluble uranyl complex to insoluble uranium dioxide.

• Korean Journal of Poultry Science
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• v.24 no.3
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• pp.153-160
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• 1997

This study was carried out to estimate the heritability and genetic correlation for body weight, shank length and shank width at various wk of age in growing Korean pheasant. All the measurements were done from one day to 20 wk of age with 4 wk interval. The heritability estimates for body weight were in the range of 0.54~0.59 for male and of 0.49~0.81 for female from 4 to 20 wk of age. The heritability estimates of male and female were in the range of 0.38~0. 82 and 0.41~0.67 for shank length, and of 0.48~0.88 and 0.49~0.71 for shank width, respectively. Genetic and phenotypic correlation coefficients between the measurements at different ages in each trait of body weight, shank length and shank width were medium to high positive values. Because the estimates of heritabilities and genetic correlations were high, the genetic gain for body weight is expected by either a direct selection or an early selection based on the record of early growing stage.

• Journal of Korean Academy of Nursing
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• v.38 no.1
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• pp.55-63
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• 2008

Purpose: The purpose of this study was to examine the relationship between eating disorders and parent-adolescent communication in middle school students. Method: There were 267 adolescents taken as participants from two middle schools in rural areas. Data were collected from June to July 2005, using the Eating Disorder Inventory-2 questionnaire (23 items) and Parent-Adolescent Communication Inventory (10 items for open family communication, 10 items for problem in family communication). The SPSS Win version 12.0 was used for descriptive analysis, t-test, and partial correlation coefficient. Result: The mean score on the eating disorder was 2.74 (range: 1-6). Meanwhile, the mean scores on the parent-adolescent communication was 3.37 (range: 1-5). There were significant differences in eating disorders according to gender, age, negative perception of the participant's body weight, family's perception of obesity, diet experiences, and BMI. Eating disorders showed a significant negative correlation with parent-adolescent communication. Conclusion: In this study, there was a significant negative correlation between eating disorders and parent-adolescent communication. In order to prevent an eating disorder, education and training to enhance communication skills should be provided to adolescents and their parents as well.

• Journal of Electrical Engineering and Technology
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• v.10 no.4
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• pp.1752-1758
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• 2015

This paper presents partial discharge localization in stator winding of generators using multi-conductor transmission line (MTL) and RLC ladder network models. The high-voltage (HV) winding of a 6kV/250kW generator has been modeled by MATLAB software. The simulation results of the MTL and the RLC ladder network models have been evaluated with the measurements results in the frequency domain by applying of the Pearson’s correlation coefficients. Two PD generated calibrator signals in kHz and MHz frequency range were injected into different points of generator winding and the signals simulated/measured at the both ends of the winding. For partial discharge localization in stator winding of generators is necessary to calculate the frequency spectrum of the PD current signals and then estimate the poles of the system from the calculated frequency spectrum. Finally, the location of PD can be estimated. This theory applied for the above generator and the simulation/measured results show the good correlation for PD Location for RLC ladder network and MTL models in the frequency range of kHz (10kHz<f<1MHz) and MHz (1MHz<f<5MHz) respectively.

• Asian Oncology Nursing
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• v.8 no.2
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• pp.86-92
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• 2008

Purpose: This study was designed to investigate the body-image and quality of life in breast cancer patients with mastectomy. Methods: Data were obtained by self-reported questionaries from 110 patients undergone mastectomy from August 1 to 31, 2007. And data were analyzed using SPSS/PC WIN 12.0 program and frequency, percentage, mean, minimum, maximum, t-test, ANOVA, Scheffe test, Pearson's Correlation Coefficient were used. The results of the study were as follows; 1) Mean of Body image of the subjects was $52.54{\pm}6.67$ (range of scale; 17 to 85). Mean of quality of life was $118.01{\pm}34.37$ (range of scale; 0 to 10). 2) There was no significant difference with the score of body image by demographic and disease-related characteristics of subjects. 3) There was significant difference with the score of quality of life by the work type and economic status of subjects. 4) Relationship between body image and quality of life showed moderately strong positive correlation (r=0.408, p<0.0001). Conclusion: Mean of body image and of quality of life in mastectomy patients were moderate. Relationship between body image and quality of life showed moderately strong positive correlation. Therefore, for improving the quality of life, it is needed to improve body image in breast cancer patients with mastectomy.

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 2001.02a
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• pp.292-309
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• 2001

Modulus of elasticity, modulus of rigidity, damping ratio, and natural frequency of three varieties of boxthorn(Lycium chinense Mill) (Cheongyang #2, Cheongyang gugija, and Cheongyang native) branches were analyzed. Modulus of elasticity and modulus of rigidity of the boxthorn branch was determined using standard formula after simple beam bending and torsion test, respectively, using an universal testing machine. Damping ratio and natural frequency of branches were determined using a system consisted of an accelerometer, a PC equipped with A/D converter, and a software for data analysis. Relationship between the elastic modulus and branch diameter in overall varieties and branch types showed a good correlation (r$\cong$-0.81). There was, however, no correlation between torsional rigidity and branch diameter. The internal damping results were highly variable and the overall range of the damping ratio of the boxthorn branch was 0.014 -0.087, which indicated that the branch was a lightly damped structure. The natural frequency of the boxthorn branch was in the range of 89-363 rad/s for the overall varieties and branch types. A good correlation (r$\cong$0.82) existed between the natural frequency and branch diameter in overall varieties and branch type.

• Asian-Australasian Journal of Animal Sciences
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• v.9 no.6
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• pp.723-726
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• 1996

A water loaded pressure device using water as the breaking force was developed to evaluate eggshell strength and compared with a dropping ball techniques. Further, relationships of shell thickness and weight of eggs to shell strength were also studied. Values for both of the shell strength measuring methods showed a highly significant correlation (p < 0.001) with shell thickness. The water loaded pressure method had a much higher simple correlation coefficient for shell thickness (r = + 0.786) than the dropping ball method (r = + 0.577). The shell strength measured by the water loaded pressure method appeared not to be correlated to egg weight. On the other hand, the negative sign of the standard partial regression coefficient and the partial regression coefficient of egg weight in the estimated multiple regression equation implied that for a given shell thickness a larger egg tended to have less shell strength than a smaller egg.

• Magazine of the Korean Society of Agricultural Engineers
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• v.43 no.2
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• pp.78-84
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• 2001

The daily streamflow in the Yaluhe watershed located in the north-eastern part of China was simulated by DAWAST model and the water balance parameters of the model were calibrated by simplex method. Model verification tests were carried out. The range of root mean square error was 0.34∼1.50mm, that of percent error in volume was -16.9∼-62.0% and that of correlation coefficient was 0.727∼0.920. DAWAST model was revised to consider the phreatic evaporation from the ground water in the frozen soil by adjusting soil moisture content in the unsaturated layer at the end of the melting season. The results of estimation of the daily streamflow by the revised model were statistically improved, that is, the range of root mean square error was 0.31∼1.49mm, that of percent error in volume was -11.7∼-12.1%, and that of correlation coefficient was 0.810∼0.932. The accuracy of DAWAST model was improved and the applicability of DAWAST model was expanded to the frozen region.

• Journal of the Korean Society for Precision Engineering
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• v.23 no.4 s.181
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• pp.168-175
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• 2006

This paper presents surface matching algorithms that can be used to reconstruct the surface topography of an object scanned by an AFM. The essence of the algorithms is to match up neighboring images intentionally overlapped with others. Two performance indexes using the correlation coefficient and the sum of the squared differences are introduced. To compensate for the inaccuracy of the coarse stage implemented to AFM, all the six axes including the rotational degrees of freedom are successively matched so as to maximize the coefficients defined. The results show that the proposed algorithms are useful for measurement range extension of AFM. The results also show that a combined use of the two indexes is beneficial for practical cases.