• Transactions of the Korean Society of Mechanical Engineers A
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• v.27 no.6
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• pp.923-929
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• 2003

In this paper, an analysis of fatigue crack growth behavior from a statistical point of view has been carried out. Fatigue crack growth tests were conducted on sixteen pre-cracked compact tension (CT) specimens of the pressure vessel (SPV50) steel in controlled identical load and environmental conditions. The assessment of the statistical distribution of fatigue crack growth experimental data obtained from SPV50 steel was studied and also the correlation of the parameter C and m in the Paris-Erdogan law was discussed. The probability distribution function of fatigue crack growth life seems to follow the 3-parameter Weibull. The fatigue crack growth rate seems to follow the 3-parameter Weibull and the log-normal distribution. The coefficient of variation (COV) of fatigue crack growth life was observed to decrease as the crack grows. Fatigue crack growth rate data shows a normal distribution for both m and logC. A strong negative linear correlation exists between the coefficient C and the exponent m.

• Journal of Environmental Science International
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• v.21 no.5
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• pp.613-622
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• 2012

A pilot-scale pulse-jet bagfilter was designed, built and tested for the effects of four operating conditions (filtration velocity, inlet dust concentration, pulse pressure, and pulse interval time) on the total system pressure drop, using coke dust from a steel mill factory. Two models were used to predict the total pressure drop according to the operating conditions. These model parameters were estimated from the 180 experimental data points. The empirical model (EM) with filtration velocity, areal density, inlet dust concentration, pulse interval time and pulse pressure shows the best correlation coefficient (R=0.971) between experimental data and model predictions. The empirical model was used as it showed higher correlation coefficient (R=0.971) compared to that of the Multivariate linear regression(MLR) (R=0.961). The minimum pulse pressure predicted by empirical model (EM) was 5kg/$cm^2$.

• Bulletin of the Korean Chemical Society
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• v.30 no.1
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• pp.67-76
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• 2009

The development of a variety of methods like AM1, PM3, PM5 and DFT now allows the calculation of atomic and molecular properties with high precision as well as the treatment of large molecules with predictive power. In this paper, these methods have been used to calculate a number of quantum chemical descriptors (like Klopman atomic softness in terms of $E_n^{\ddag}\;and\;E_m^{\ddag}$, chemical hardness, global softness, electronegativity, chemical potential, electrophilicity index, heat of formation, total energy etc.) for 75 alkanes to predict their boiling point values. The 3D modeling, geometry optimization and semiempirical & DFT calculations of all the alkanes have been made with the help of CAChe software. The calculated quantum chemical descriptors have been correlated with observed boiling point by using multiple linear regression (MLR) analysis. The predicted values of boiling point are very close to the observed values. The values of correlation coefficient ($r^2$) and cross validation coefficient ($r_{cv}^2$) also indicates the generated QSPR models are valuable and the comparison of all the methods indicate that the DFT method is most reliable while the addition of Klopman atomic softness $E_n^{\ddag}$ in DFT method improves the result and provides best correlation.

• Water for future
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• v.19 no.4
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• pp.347-354
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• 1986

To predict flood runoff from rainfall and watershed Characteristics, Nash's parameters of N, K are needed to be determined. Also parameters of IUH N and K are derived by the moment method. Nash's model whose parameters are derived from rainfall characteristics is applied to the Wi-stream basin, which is a tributary located in the Nakdong river. For the derivation of IUH by applying linear conceptual model, the storage constant, K, with the rainfall characteristics was adopted as K=1.327 $$.$$$.$$$.$$$.$$$.$$ having a highly significant correlation coefficient, 0.970. Gamma function argumetn, N, derived with such rainfall characteristics was found to be N=0.032$$.$$$.$$$.$$$.$$$.$$ having a highly significant correlation coefficient, 0.970. From the tested results it is proved that Nash's IUH and consequently flood runoff can be predicted from rainfall characteristics.

• Journal of Distribution Science
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• v.17 no.7
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• pp.39-44
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• 2019

Purpose - This research was to help distribution of Go Bags (Survival Bag or Disaster Supplies Kit), which are useful for disaster preparedness, by surveying precomposed Go Bag items in internet shopping malls. Research design, data, and methodology - We checked 15 items including food, water, first aid kit, radio, flashlight or candles, battery, lighter or matches, whistle, blanket, towel, toilet paper, personal sanitations, raincoat, can opener, disaster manual in Go Bags based on the recommendations by the Ministry of the Interior and Safety. The number of items and price, domestic product, accreditation were compared using a Chi-square test. The Pearson's R was also used to summarize the strength of the linear relationship between the number of items and price, sub-items. Results - Mean of the sub-items was 21, and mean of the items was 8. There was a statistically significant difference between the number of items size and the price level (p=.014). There was also a statistically significant difference between the number of items and sub-items (p<.001), and correlation coefficient was a positive linear relationship of .467. Conclusions - Only eight were sold in the internet shopping malls as a precomposed Go Bag items. Even the approved Go Bags had no difference in the number of items. Higher prices had a relatively greater number of items, and it had a positive correlation between the size of sub-items and items.

• Journal of The Korean Society of Agricultural Engineers
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• v.58 no.1
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• pp.61-71
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• 2016

This study performed the physical and mechanical experiment on the samples of costal marine clays individually collected in western and southern regions to identify the characteristics of western and southern costal marine clay. Based on the experiment result, the characteristics of costal marine clay is identified undrained shear strength. Based on the experiment result on the physical and mechanical characteristics of costal marine clays, the regression is presented that can analyze the mechanical characteristics of undrained shear strength in costal marine clay of Korea, region of Korea and western-southern region. The correlation of uniaxial compressive strength and undrained shear strength was suitable for use of western-southern region correlation equation. The test result of Jeonnam Yeosu area compares with prediction results of previous researchers formula and western-southern region formula. Prediction results appear highest reliability on the 0.827 of coefficient of determination in the prediction results of the western-southern region formula.

• Journal of Ecology and Environment
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• v.32 no.1
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• pp.61-65
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• 2009

We compared two nondestructive methods for leaf area estimation using leaves of 16 common plant species classified into six types depending on leaf shape. Relatively good linear relationships between actual leaf area (LA) and leaf length (L), width (W), or the product of length and width (LW) were found for ordinary leaves with lanceolate, oblanceolate, linear and sagitttate shapes with entire margins, serrate margins, mixed margins with a entire form and shallow lobes, and ordinary incised margins. LA was better correlated with LW than L or W, with $R^2$ > 0.91. However, for deeply incised lobes, LA estimation using LW showed low correlation coefficient values, indicating low accuracy. On the other hand, a method using photographic paper showed a good correlation between estimates of area based on the mass of a cut-out leaf image on a photographic sheet (PW) and actual leaf area for all types of leaf shape. Thus, the PW method for LA estimation can be applied to all shapes of leaf with high accuracy. The PW method takes a little more time and has a higher cost than leaf estimation methods using LW based on leaf dimensions. These results indicate that researchers should choose their nondestructive LA estimation method according to their research goals.

• KIPS Transactions on Software and Data Engineering
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• v.5 no.7
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• pp.333-338
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• 2016

This study is to estimate proximity without direct measurement of the weight of fresh ginseng. For this work, we developed a ginseng image acquiring instrument and obtained 126 ginseng images using the instrument. Image analysis and parameter extraction process was used C language based Labwindows/CVI development tools and open source library OpenCV. Estimation formula is made by weighing the sample with image analysis of fresh ginseng. We analyzed the correlation between the pixel number and the weight of ginseng using a linear regression approach. It was obtained a strong positive correlation coefficient of 0.9162 with a linearity value.

• Journal of the Korea Convergence Society
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• v.7 no.6
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• pp.81-88
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• 2016

This study is descriptive correlational research to analyze converging influence of empathy and prejudice on discriminatory behavior toward the mentally illness patients in the nursing students. Research objects are 175 students of department of nursing and who understand purpose of this study and agree with participate in this study. Collected Data were analyzed t-test, ANOVA, Pearson's correlation coefficient, Linear Regression by IBM SPSS 21.0 program. As a result empathy increased prejudice and discriminatory behavior on mentally illness patients was reduced. And prejudice against mentally illness patients was increased discriminatory behavior. In addition, factors that affect the discriminatory behavior of the mentally illness patients are gender, prejudice and empathy. In order to reduce prejudice and discriminatory behavior on mentally illness patients of nursing college students suggest that brief training program and the need for promoting empathy in the nursing curriculum.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.14 no.5
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• pp.2271-2280
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• 2013

This study is a descriptive research carried out to investigate the knowledge, confidence and attitude on cardiopulmonary resuscitation(CPR) of university students studying health care and figured out the factors affects their attitudes on CPR. 516 health-care university students were informed with the agreement of this study. The data were analyzed with t-test, one-way ANOVA, Pearson's correlation coefficient and Multiple linear regression were used. There were significant positive correlations between the attitude and knowledge(r=.269, p<.001) and between the attitude and confidence (r=.620, p<.001) on CPR. It was found that the influential factors for the attitude on CPR include confidence, gender, knowledge, personality, perception, education experience in CPR, experiences in medical service and the reason for choosing the subject and their persuasive power was 49%. Programs and educations enhancing knowledge and positive attitude on CPR is needed, and there needs to be developing in a proactive manner.