• Korea-Australia Rheology Journal
• /
• v.14 no.4
• /
• pp.143-159
• /
• 2002

Although much progress has been made in the computation of Eulerian steady flows with high viscoelasticity, less work has been done for the case of transient flows. Because of their importance in injection moulding, blow moulding and other forming processes, as well as their Intrinsic interest, we believe more attention should be focussed in this area. Hence in this paper we review progress in unsteady flow computations with high elasticity, and show some new results in this area.

• Journal of Wetlands Research
• /
• v.23 no.4
• /
• pp.296-306
• /
• 2021

Elasticity is a statistical technique that interprets the changing pattern of another variable according to a change in one variable as a quantitative numerical value and provides more information than correlation analysis and is widely used in climate change research. In this study the elasticity was calculated and sensitivity analysis was performed using air temperature and water quality data of the major tributaries of the Nakdong River. In addition the confidence interval for the elasticity was calculated using the T-Test and the validity of the elasticity was examined. The strength of elasticity shows high strength in the order of summer>fall>spring>winter and the direction shows regional characteristics with both negative and positive elasticity. After performing hierarchical cluster analysis on monthly observation data they were classified into 5 clusters and the characteristics of each cluster were visually analyzed using a parallel coordinate graph. The direction and intensity of the air temperature elasticity show regional characteristics due to the relatively high population density and complex influencing factors such as sewage treatment plants, small-scale livestock houses and agricultural activities. In the case of TP it shows great regional variability according to the circulation of nutrients in the ecosystem caused by algae growth and death according to temperature changes. Since the air temperature elasticity of the major tributaries of the Nakdong River is over weak and is valid at the significance level of 5%, it was analyzed that there is a change in water quality according to the air temperature change.

• Journal of Wetlands Research
• /
• v.22 no.3
• /
• pp.178-186
• /
• 2020

In this study, the elasticity was calculated and sensitivity analysis was performed using air-water temperature data of the major tributaries of the Nakdong River. We developed a nonparametric elasticity analysis technique capable of estimating the confidence interval for elasticity and verifying the hypothesis, and examined its applicability compared to the existing method using the median value. It is analyzed that the elasticity of winter is low and the elasticity of summer and autumn is high, so that the fluctuation of water temperature and water quality according to the fluctuation of air temperature is large. The spatial elasticity tends to be low in the Geumho River area, which is influenced by artificial factors such as sewage treatment plant effluent, small and medium-sized livestock wastewater, and small-scale factory wastewater. Since the elasticity of major tributaries of the Nakdong River is over weak and is reasonable at a significance level of 5%, it was analyzed that the air-water temperature fluctuation caused by climate changes is large.

• Journal of the Korea Concrete Institute
• /
• v.12 no.6
• /
• pp.23-34
• /
• 2000

This paper reports the effects of curing temperature and aging on the strength and the modulus of elasticity. In oder to determine the strength and the modulus of elasticity with curing temperature and aging, experimental and analytical methods are adopted. The tests of 480 cylinders are carried out for type I, V and V with 15 percent replacement of fly ash cement concretes, which are cured at isothermal conditions of 10, 23, 35 and 5$0^{\circ}C$. and the concrete cylinders are tested at the ages of 1, 3, 7 and 28 days. According to the experimental results, the concrete subjected to high temperature at early ages attaines higher early-age compressive and splitting tensile strength but eventually attaines lower later-age compressive and splitting tensile strength. Even if modulus of elasticity has the same tendency, the variation of modulus of elasticity with curing temperature is smaller than that of compressive strength. Based on these experimental results, the relationships among compressive strength, modulus of elasticity and splitting tensile strength are proposed considering the effects of curing temperature, aging and cement type.

• Journal of Korean Society of Forest Science
• /
• v.98 no.2
• /
• pp.148-155
• /
• 2009

The objective of this study is to know market structures of softwood logs being imported to South Korea from log producing countries. Import demand of softwood logs imported to South Korea from America, New Zealand and Chile is fixed as a function of log prices, the lagged dependent variable and output. On the basis of the adaptive expectations model, linear regression models that the explanatory variables included and the lagged dependent variable were estimated by Seemingly Unrelated Regression Equations (SURE). The short-run and long-run own price elasticity of America's softwood log import demand is -1.738 and -4.250 respectively. Then long-run elasticity is much higher than short-run elasticity. Short-run and long-run crosselasticity of New Zealand's softwood log import demand with respect to American's softwood log import price are inelastic at 0.505 and 0.883 respectively. Short-run and long-run cross-elasticity of Chile's softwood log import demands with respect to American's softwood log import prices were highly elastic at 2.442 and 4.462 respectively. Long-run elasticity was almost twice as high as short-run elasticity.

• The Journal of Korean Obstetrics and Gynecology
• /
• v.25 no.4
• /
• pp.46-55
• /
• 2012

Objectives: It is well known that genetic factors and environmental factors play major role in aging skin. In general, son and daughter take after their parents in appearance. But comparability of skin properties in Korean family has not been well estimated. So we evaluated the correlation of skin properties in Korean mother-daughter pairs. Methods: 10 couples of mother and daughter pair(n=20) participate in this study. Mothers and daughters were aged $50.6{\pm}2.459$ and $23.8{\pm}2.15$ years, respectively. Skin moisture, sebum, skin color and elasticity is measured using non-invasive method : Corneometer CM825, Sebumeter(MPA580), Mexameter MX18, Cutometer MPA580. Statistical analysis program we used is Minitab 14 Korea. Results: The Skin moisture of mother group was significantly higher than daughter group. And skin elasticity(R2) of the daughter group was significantly higher than mother group. In the results of correlation analysis between mother and daughter pairs, skin elasticity(R2) had high positive correlation(r=0.729, p=0.026). But skin moisture, sebum, melanin index, erythema index and skin elasticity(R5) did not be confirmed a significant correlation. Conclusions: Skin elasticity(R2) is the only factor that showed high positive correlation significantly in mother and daughter pairs. Mother and daughter share the genetic factors and environmental factors that influence skin aging. So, mother's aging pattern will be a good guide for anti-aging of daughters.

• Proceedings of the Korea Concrete Institute Conference
• /
• 2001.05a
• /
• pp.31-36
• /
• 2001

This paper report the effects of mix ingredients on the modulus of elasticity of high-strength concrete. The test of 284 cylinder specimens are conducted for type I with 10% replacement of fly-ash cement concretes. Different water-binder ratio, amounts of water and coarse aggregate as variables were investigated. And also analyzed it statistically by using SAS.

• Journal of the Korean Recycled Construction Resources Institute
• /
• v.2 no.3
• /
• pp.202-208
• /
• 2014

For evaluating basic structural behavior of HVFA (High Volume Fly Ash) concrete, several tests are performed considering different ratios of fly ash replacement and structural evaluation regarding compressive strength, elasticity modulus, stress-strain relationship, and bond strength is also performed. Test results show that elasticity modulus of HVFA concrete has close relationships with compressive strength and fly ash replacement ratio. The ultimate strain shows slight difference from domestic design code. On the other hand, there are no differences between general concrete and HVFA concrete for elasticity modulus and bond strength.

• Journal of the Korean Society of Clothing and Textiles
• /
• v.27 no.5
• /
• pp.545-553
• /
• 2003

A good school uniform leads students to good behavior and have them enjoy desirable school life. Therefore a better fabric for girls' high school uniform suggested through two series of studies; first, examined the various aspects of current uniforms. Second, made a new fabric for uniform considering elasticity for activity and comfortableness, and compared its characteristics with those of the current uniforms. The results are as follows; 1 Most of students wanted uniforms considering elasticity for activity and wearing. 2. The measurement of the elasticities of the uniform materials showed that the material which was made using the elastic material was more elastic than the currently used material by 42.12% in summer material and 20.05% in winter one. 3. The analysis using the combination of the values of mechanical properties showed that the elastic material was better in the wearing, tactile senses, and drape properties than the current material, even though it was a little worse in shape-stability. 4. To compare the thermal insulation, clo values were measured. For winter uniform, the elastic material was better than the current one in keeping warm. However, This study did not find any big difference between summer uniform materials.

• The Journal of Korean Society for School & Community Health Education
• /
• v.16 no.1
• /
• pp.1-14
• /
• 2015

Objectives: The purpose of this study was to examine the effects that the self-efficacy, self-elasticity, and major satisfaction of students majoring in dental hygiene would have on the adaptation to the campus life. Methods: The total 396 students were surveyed who majored in dental hygiene in universities located at Gyeongbuk and Gyeongnam from October 15, 2013 to October 30. The collected data were analyzed by using the SPSS 17.0 program, along with the One-Way ANOVA, correlation analysis, and multi-regression analysis. Results: The 'aptitude and interest' were found to be greatest factor among the motive for application among the factors of self-efficacy, self-elasticity, and major satisfaction of students, depending on general characteristics. The results of correlation analysis showed that the self-elasticity had a correlation of 0.741 and the adaptation to the study had a correlation of 0.420 in the self-efficacy, while the individual emotional adaptation, adaptation to university environment, and adaptation to the study had a correlation as high as over 0.4 in the self-elasticity(p<0.05). In addition, it was found that the adaptation to the campus life increased proportionally to the self-elasticity and major satisfaction(p<0.05). Conclusions: To increase the campus life adaptation of students majoring in dental hygiene, it is considered necessary to explore the measures that can improve the self-elasticity and overall major satisfaction.