• Proceedings of the Korea Water Resources Association Conference
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• 2002.05b
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• pp.1334-1339
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• 2002

The objective of this study is to help practicing engineers easily use the Clark model which is used for estimating the magnitude of design flood for small stream. A representative unit hydrograph was derived on the basis of the past rainfall-runoff data and unit hydrographs, and the storage coefficient of Clark model was estimated by using hydrograph recession analysis. Since the storage coefficient(K) is a dominating factor among the parameters of Clark method, a mulitple regression formula, which has the drainage area, main channel length and slope as parameters, is propsed to estimate K value of a basin where measured data are missing. The result of regression analysis showed that there is a correlation between a storage coefficient(K) and aforemetioned three parameters in homogenious basins. A regression formular for K was derived using these correlations in a basin of Han River, Nakdong River, Young River, Kum River and Sumjin River

• Korean Journal of Clinical Laboratory Science
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• v.48 no.3
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• pp.196-201
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• 2016

An effective strategy for obesity intervention should include demographic, health-related, and work-related factors that are most relevant to the target population. Factors most strongly associated with obesity may differ for groups of individuals across industries or age categories. The purpose of this study was to provide current knowledge about the possible association between psychosocial job stress and immune parameters in blood. We assessed obesity-related parameters as well as the natural killer cell activity (NKCA) in female workers. There was a significant difference in the obesity-related blood parameters, i.e. fasting blood sugar level, according to age (p<0.05). Moreover, it showed a significant difference in NK cell activity between the obese and non-obese factor groups (p<0.05). Pearson correlation analysis demonstrated that NKCA was closely correlated with obesity related factors. In the future, it would have to study the biological changes which increase the activity of the immune factors to the immunological response.

• Journal of the Korean Society of Food Science and Nutrition
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• v.43 no.6
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• pp.859-867
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• 2014

This study was conducted to investigate the relationship between quality factors and palatability of onion by cultivation region and variety. Six onion varieties harvested in four regions were subjected to physicochemical, microbiological, and sensorial evaluation. There were differences in soluble solid content, color, vitamin C, quercetin, total polyphenol, and pyruvic acid contents among the varieties and cultivation regions. Dry weight and pH of onions did not significantly differ. Overall acceptability and palatability did not show any significant differences by variety. From the correlation and regression analysis, palatability was very closely related to $Z_{11}$ (acridity) of -0.914 and the regression equation for sensorial palatability (Y) was $Y=12.3806-0.8284Z_{10}(sourness)-0.7957Z_{11}(acridity)$ with a coefficient of 0.9140.

• International Journal of Highway Engineering
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• v.7 no.4 s.26
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• pp.1-8
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• 2005

Permanent Deformation is one of the most important load-related pavement distresses in asphalt pavements. The Korean Pavement Design Guide currently being developed adopted the mechanistic-empirical approach and needed the pavement distress prediction models. This study intends to develop the model for prediction of permanent deformation in the asphalt layer and estimate the pavement performance. The objectives of this paper are to figure out the factors affecting the permanent deformation and then develop the permanent deformation prediction model for asphalt mixtures. The repeated triaxial load test was Performed on the 19mm dense graded asphalt mixture with variation of temperature and air void. Results from the laboratory tests showed that temperature and air void in asphalt mixtures have significantly influenced on the factors in prediction model. The permanent deformation prediction model for 19m dense grade asphalt mixtures has been developed using the multiple regression approach and validated the proposed permanent deformation prediction model.

• Journal of the Korean Chemical Society
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• v.48 no.2
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• pp.156-160
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• 2004

The extraction rates of plasticizer of LPG high pressure rubber are studied. Submerging solvents are composed of propane, n-butane, n-pentane, n-hexane, n-heptane, propylene, 1,3-butadiene, 1-pentene, 1-hexene, ethanethiol, t-butanethiol, dimethyl sulfide, methyl ethyl sulfide. The relationship between the extraction rate of plasticizer and the descriptors of submerging solvent by using multiple linear regression is as follows; PE(wt%) = 7.5193 - 0.58500Carbon${\sharp}$ + 2.3294DB + 2364SH, (N = 13, F = 24.135, R$^2$ = 0.8894, R$_{adj}^2$ = 0.8526, Variance = 7.588) Plasticizer is well extracted by LPG composed of the high vapour pressure and polarity compounds. The mass of extracted plasticizer becomes increasing in proportion to the contents of thiol sulfur compound and unsaturated hydrocarbon such as propylene and 1,3-butadiene in LPG. While the heavier hydrocarbons are, the less the quantities of plasticizer extracted from rubber are.

• The Journal of Dong Guk Oriental Medicine
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• v.6 no.2
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• pp.167-190
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• 1998

Nowadays there were two tendencies of studies about prognostic factors in stroke. One way was to define prognostic factors according to the radiological features. And the other way was to define according to the mental state, recognition, perception, motors, language, urinary&bowel incontinence etc.. The former could be objectively investigated, while the latter was difficult. The purpose of this study was to determine which variables would be predictors of stroke and which factors would be affect predictions most. The subjects of this study were 32 patients who were admitted to the Dept. of Internal Medicine, Dongguk Univ. College of Oriental Medicine whthin 48 hours from attack, Medical records were reviewed FIM, CNS, NIH stroke scale. We compared each sub-items of FIM, CNS, NIH stroke scale about mental state, recognition, perception, motors, language, urinary&bowel incontinence with MBI score at 4 weeks from admission. Also, we analyzed the correlations of sub-items and groups which devided into 5 according to independence of MBI score. And we found out the most influent factors with multiple regression analysis. The major results were as follows; 1. In mean of MBI score at 4 weeks of each groups devided low, middle, high score at mental state, recognition, perception, motors, language, urinary&bowel incontinence items, there were statistical differences in all items. 2. The mental state and lim ataxia sub-items had no significant correlations with groups divided according to independence of MBI score. All the other items were significantly correlated. 3. The most influent factors was recognition. The second was sensory and the third was bowel incontinence. 4. The most influent scales was FIM, and the second was CNS, and NlH had no statistical significancy.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.38 no.4
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• pp.587-593
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• 2018

The current road traffic noise prediction programs of Korea, which are widely used, are based upon foreign prediction model. Thus, it is necessary to verify foreign prediction models to find out whether they are suitable for the domestic road traffic environment. In addition, an analysis and an in-depth study on the main factors should be conducted in advance as the influence factors on the occurrence of traffic noise vary for each prediction model. Therefore, this study examined the influence factors and the existing prediction models used to forecast road traffic noise. Also, analyzed their relationship with the factors influencing the noise generated by driving vehicles through multiple regression analysis using a prediction model, taking into consideration of the traffic environment and the road geometric structure. In addition, this study will apply experimental values to the existing road traffic noise prediction model (NIER, RLS-90) and the deducted road traffic noise prediction model. As a result, the order of the absolute value sum of the errors are NIER, RLS-90, model value. Through comparison and verification, developed models are to be analyzed for providing basic research results for future study on road traffic noise prediction modeling.

• Sleep Medicine and Psychophysiology
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• v.21 no.2
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• pp.61-68
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• 2014

Objective: The aim of the present study is to assess the prevalence and related risk factors of suicide ideation among middle and high school students in an urban area. Methods: We surveyed 3,691 middle and high school students (2,159 male, 1,532 female, 11-19 years of age) using a self-report questionnaire that covered basic socio-demographic data, academic achievements, presence of physical or psychiatric illness, sleep duration on weekdays, time spent at private academies on weekdays and weekends, and subjective needs for counseling. The Beck Depression Inventory (BDI) and Reynolds' Suicidal Ideation Questionnaire (SIQ) were included in the survey. Results: The prevalence of students with high suicide ideation ($SIQ{\geq}62$) was 4.6%. In a logistic regression model, female sex (p = 0.002), younger age (p < 0.001), poor academic achievement (p = 0.043) and higher score of BDI (p < 0.001) were associated with a higher SIQ score. In addition, younger age (p = 0.045) and a higher BDI score (p < 0.001) were associated with a higher SIQ score adolescents having high suicide ideation ($SIQ{\geq}62$). Conclusion: Related risk factors of suicide ideation in adolescents were female sex, younger age, poor academic achievement, and a depressive mood. It would be especially helpful to pay more attention to younger adolescents and a depressive mood as a high-risk group. The understanding of these factors will be helpful for providing an effective suicide screening and prevention program for adolescents.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.24 no.6
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• pp.405-412
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• 1991

Whitefish(Coregonus clupeaformis) and Burbot(Lota iota) muscle was filleted, treated with dipotassium phosphate(pH 8.0) by means of high pressure injection method, and finally stored at $-l2^{\circ}C$ for 3 months. Factors, the pH, moisture content, and total amount of collagen were analyzed on the samples before and after the frozen storage. The pH of the sample showed substantially higher values in the phosphate treated muscles than the controls and decreased after 3 months storage in all of the whitefish and burbot samples, there was no significant differences in the moisture content between the control and treated but some reduction occurred during frozen storage. The amount of total collagen in the tail sections of burbot was significantly high comparing with head sections and hardness of the tail section also showed high values which indicated that total collagen might be related to the texture of fish muscle. However, in the case of whitefish the effect was not apparent. The effects of these factors on the hardness determined by Instron texturometer were analyzed through standardized multiple regression. A specific factor was not apparent to the texture of white fish while pH showed the highest correlation to the hardness of the burbot muscle.

• Neonatal Medicine
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• v.17 no.1
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• pp.64-74
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• 2010

Purpose : The aim of this study was to determine the risk factors, clinical characteristics and prognosis for the development of periventricular leukomalacia (PVL) in preterm infants according to the extent and site of the PVL. Methods : The medical records of infants (under 36 weeks of gestational age) delivered from January 1999 to December 2008 were reviewed. Twenty-five preterm infants with were PVL were diagnosed by brain magnetic resonance imaging (MRI) and an addition 50preterm infants with no brain lesions were enrolled in this study. The perinatal and neonatal risk factors for the development of PVL was determine in these infants. Mental and Psychomotor Developmental Indices (MDI, PDI) were assessed by a clinical psychologist using the Bayley Scales of Infant Development II. We compared the differences of the clinical characteristics and prognosis according to brain MRI findings. Results : Maternal fever, young maternal age, extended oxygen use, hypotension within the first week of birth, use of inotropics within the first week of birth, and respiratory distress syndrome were the risk factors associated with PVL (P <0.05). In the multivariate analysis, maternal fever and extended oxygen use were statistically significant independent risk factors (P <0.05). The mean MDI and PDI scores of the PVL group (74.4$\pm$ 27.8 and 58.0$\pm$17.7) were significantly lower than those of the control group (103.5$\pm$8.9 and 101.7$\pm$16.1, P <0.05). Conclusion : Maternal fever and extended oxygen use were independent risk factors for PVL. We should pay attention to infants who had the risk factors and follow them up closely by brain imaging study and Bayley Scales of Infant Development II.