• Advances in concrete construction
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• v.13 no.6
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• pp.411-422
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• 2022

Aggregates mineralogical, and petrographic properties directly affect the mechanical properties of the produced high strength. This study is focused on the effects of magmatic, sedimentary, and metamorphic aggregates on the performance of high strength concrete. In this study, the effect of the mineralogical properties of aggregates on the compressive strength and modulus of elasticity of high-strength concrete was estimated by Artifical Neural Network (ANN). To estimate the compressive strength and elasticity modules, 96 test specimens were produced. After 28 days under suitable conditions, tests were carried out to determine the compressive strength and modulus of elasticity of the test specimens. This study also focused on the application of artificial neural networks (ANN) to predict the 28-day compressive strength and the modulus of elasticity of high-strength concrete. An ANN model is developed, trained, and tested by using the available test data obtained from the experimental studies. The ANN model is found to predict the modulus of elasticity, and 28 days compressive strength of high strength concrete well, within the ranges of the input parameters. These comparisons show that ANNs have a strong potential to predict the compressive strength and modulus of elasticity of high-strength concrete over the range of input parameters considered.

• Journal of Nutrition and Health
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• v.43 no.3
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• pp.233-245
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• 2010

The purpose of this study was to investigate the effects of dietary habits and nutrient intakes on skin condition of female university students. The subjects were 95 female university students in Daegu. This study examined anthropometric measurements, dietary intake, food intake habits and skin condition (moisture, elasticity, sebum (U-zone, T-zone), pores, evenness and melanin pigmentation. The subjects in this study had an average age of 21.4, an average height and weight of 161.2 cm and 52.9 kg, respectively, and the average body mass index (BMI) was 20.3 $kg/m^2$. The means of skin elasticity, pores, evenness, and melanin pigmentation were within the normal range of women in their 20s and the skin moisture state was slightly lower than the normal range, which showed a dry tendency. The sebum in the U-zone and the T-zone was lower than the standard values, which showed less secretion in both areas. The subjects with high nut intake showed a better skin pore state (p < 0.05). Those with a high intake of instant foods showed a sig-nificantly low skin moisture and a significantly higher sebum rate (p < 0.05). The group with high skin elasticity and the group with less melanin pigmentation showed a significantly low animal protein intake (p < 0.05). The group with high skin elasticity also showed a significantly higher vitamin A and niacin intakes as well (p < 0.05). The group with high skin evenness showed a significantly lower animal lipid intake and a significantly higher vitamin E intake (p < 0.05). In addition, those with high skin elasticity and evenness as well as low melanin pigmentation showed a tendency of high intake of antioxidant vitamins, such as vitamin A, carotene, vitamin C or vitamin E. In summary, a moderate intake of plant-based products and also the antioxidant vitamins within such products seems to have a beneficial effect on maintaining a healthy and good skin condition.

• Journal of Drive and Control
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• v.17 no.4
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• pp.87-96
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• 2020

In this study, a variable elasticity spring was applied to improve the pressure control precision of conventional relief valves. The equilibrium equation of the forces acting on the valve poppet was derived; it is demonstrated that matching the elastic rate of the pressure-adjusting coil spring to the equivalent elastic rate of the flow force improved the pressure override. The procedures that were used to design the variable elasticity spring are presented, and some applications of the variable elasticity spring are also introduced. Computer simulations were used to analyze three cases: a poppet-closed flow force structure, a poppet-open flow force structure with a constant elasticity spring, and a structure containing a variable elasticity spring. It is confirmed that the pressure control precision of the relief valve can be significantly improved upon by applying a variable elasticity spring to the poppet-open flow force structure.

• Proceedings of the Korea Concrete Institute Conference
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• 2010.05a
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• pp.413-414
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• 2010

Many researchs shows that modulus of elasticity in manual overestimates real modulus of elasticity of concrete as strength gets higher. In 2007 KCI Manual, formula in modulus of elasticity has revised that it should be demonstrated. In this study, modulus of elasticity in high strength was estimated by experiment and experimental value was compared with manual value.

• The Journal of Korea Institute of Information, Electronics, and Communication Technology
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• v.13 no.5
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• pp.432-435
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• 2020

The elasticity tensor for water may be employed to model the fully saturated porous material. Mostly water is assumed to be incompressible with a bulk modulus, however, the upper and lower bounds of off-diagonal components of the elasticity tensor of porous materials filled with water are violated when the bulk modulus is relatively high. In many cases, the generalized Hill inequality describes the general bounds of Voigt and Reuss for eigenvalues, but the bounds for the component of elasticity tensor are more realistic because the principal axis of eigenvalues of two phases, matrix and water, are not coincident. Thus in this paper, for anisotropic material containing pores filled with water, the bounds for the component of elasticity tensor are expressed by the rule of mixture and the upper and lower bounds of fully saturated porous materials are violated for low porosity and high bulk modulus of water.

• The Journal of the Korea Contents Association
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• v.20 no.1
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• pp.644-657
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• 2020

As the development of urbanization has cause some environmental problems and natural disasters such as natural earthquakes and floods have brought about impact, designers have turned their attention to the independent prevention ability of urban ecosystems in face of environmental pollution and natural disasters, as well as its ability to adapt to the future. This study introduces 'elasticity theory' to discuss the practical application of elasticity design in landscapes and to solve the problem of lack of elasticity in space, which can provide more scientific reference meaning to create economic, cultural, and social values for space. After selecting 'The High Line' as the object, this paper investigates the previous theories and practical cases, and infers ecology, sustainability, diversity, and adaptability. And then this paper applies five components and analyzes the specific application of these five components of the landscape spatial elasticity strategy, and summarizes the application characteristics and influencing factors of elasticity design in 'The High Line' landscape planning. It can be known from the research that elasticity strategy which is reflected in the design process is the systematic management of landscape space. Elasticity design itself can strengthen environment quality and satisfy the requirements of the environment to defense external shocks so as to adapt to environment changes. Therefore, the elasticity design can strengthen the sustainable development of the city and establish a periodic recycle system.

• Korean Journal of Community Nutrition
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• v.4 no.4
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• pp.587-593
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• 1999

The purpose of this study were to : (a) analyzed price elasticity of university students in foodservice operations and (b)provide insight for price decision-making. Questionnaires were composed of price elasticity, the utilization and opinions of students on university foodservice operations, and demographic information regarding respondents. The questionnaires were distributed to 600 university students of 6 universities located in Seoul. Statistical data analysis was completed using the SAS package for descriptive analysis, t-test, ANOVA, and Pearson’s correlation. The results of this study can be summarized as follows: The average price for lunch was ￦1,663 for campus food, and ￦2,965 for off-campus restaurants. The frequency of utilizing the university cafeteria was fairly high. Students felt that the proper price for lunch was ￦1,446, presenting a lower price than the actual average price for lunch. The price elasticity was investigated in relation to the change in utilization rate when these was a price increase. The price elasticity was 2.03, with significant differences between sex, age, and major. The groups utilizing the university cafeteria frequently, taking longer time to go to off-campus or that were satisfied with the university cafeteria, had a lower price elasticity than those that did not. The results of this study suggest that predicting the price elasticity of the target market would assist the pricing policy, and the fact that the same students have different price elasticity by place and atmosphere can be used in marketing strategies.

• Journal of the Korean Wood Science and Technology
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• v.23 no.2
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• pp.32-36
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• 1995

A study was conducted to evaluate the dynamic mechanical properties (modulus of elasticity, resonant frequency and interanal friction) of compression wood in Pinus densiflora. Vibration method was used for estimation of dynamic modulus of elasticity and the values were compared to those of static bending modulus of elasticity. The results obtained are as follows: 1. The dynamic modulus of elasticity of compression wood decreased, whereas that of normal wood increased, with increasing specific gravity. 2. The resonant frequency of compression wood decreased, whereas that of normal wood increased, with increasing specific gravity. 3. The internal friction of compression wood increased with increasing specific gravity. 4. The correlation coefficients between dynamic and static moduli of elasticity in compression and normal woods were high.

• Journal of the Korean Society of Radiology
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• v.15 no.6
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• pp.883-889
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• 2021

This study was conducted on 101 patients who visited hospital for abdominal ultrasonography from May 2020 to December 2020. The purpose of this study was to find out the elasticity according to the ultrasound images (echo pattern, splenomegaly, hepatitis) during the ultrasound examination using the shear wave elastography. The shear wave elastography value of the normal group of the echo pattern was 5.75±1.58 kPa, and the group with the abnormal echo pattern was 8.84±4.94 kPa, and the shear wave elastography value of the abnormal group was high (p<0.05). In normal spleen size, hepatic elasticity value was 6.33±2.54 kPa, and hepatic elasticity value of splenomegaly was 13.73±5.48 kPa. In the case of splenomegaly, the liver elasticity value was high, and there was a statistically significant difference (p<0.05). As the spleen size increased, the liver elasticity value increased by 1.485 times, and as hepatitis progressed, the liver elasticity value increased by 1.573 times (p<0.05). As a result of analysis of concordance between ultrasound imaging findings and shear wave elastography, the Kappa value was found to be as high as 0.922 (p<0.05), which showed high concordance between the two test methods. Additional comparisons of liver elasticity values in shearwave elastography tests along with liver ultrasound findings are thought to be of great help in diagnosing liver fibrosis.

• Korea Trade Review
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• v.46 no.4
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• pp.219-234
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• 2021

Armington elasticity has been a methodology for analyzing how much imports could increase in response to importing price cuts, assuming the possibility of incomplete substitution of domestic and imported products. This study calculates Armington elasticity values in Korean fisheries sector and presents an analysis method for classifying items based on price and preference differences. The model is modified reflecting the characteristics of the fisheries market along with the typical OLS, PAM, and ECM models. The result's implication is that products with a high import growth rate do not necessarily show a high Armington value, but it could be seen that price is not the only factor facilitating fisheries imports increase. Considering the items of which demand increases due to importing price cuts have an indiscriminate demand between domestic and imported products, the results could be interpreted that the Korean fisheries importing market has been easily affected by the changes in import prices. Fisheries grouping by price and preference demonstrates that explanatory variables other than price should be considered when estimating import demand.