• 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.

• Journal of the Korean Society of School Health
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• v.21 no.2
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• pp.47-60
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• 2008

Objectives: The purpose of this study was to compare Fast foods and Soft drinks consumption of Korean adolescents in a large city, a medium city, and a rural area. Methods: This was a descriptive comparative survey using a convenience sample of 2,261 8th and 11th grade students. The data were analyzed by X2-test and ANOVA using SPSS 10.0 statistical program. Results: For fast food consumptions, the higher in a large city than in a medium city and a rural area(p=.000). For soft drinks in a school, cafeteria or vending machines was higher in a large city and a medium city then in a rural area(p=.000). For eating snacks including cookies and popcorns was higher among students in a rural area than those in a medium city and large city(p=.008). Conclusions: 1. Overall, the health information among rural students is lower than those among other areas, as well as taking a health education course among rural students is also lower. Thus, the health inequality by regional differences should be considered. To decrease health inequality among different regions, health professionals who can systematically teach a health education course for middle and high school students and undertake students' health are needed. 2. Soft drinks sold in schools are higher in a large city and medium city than in a rural area. Therefore, there is a need of strong regulations and policies about the restriction of soft drinks sold in vending machines or school cafeterias.