• Journal of Preventive Medicine and Public Health
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• v.40 no.5
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• pp.371-380
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• 2007

Objectives: To determine the impact of cigarette prices on the decision to initiate and quit smoking by taking into account the interdependence of smoking and other behavioral risk factors. Methods: The study population consisted of 3,000 male Koreans aged ${\ge}20$. A survey by telephone interview was undertaken to collect information on cigarette price, smoking and other behavioral risk factors. A two-part model was used to examine separately the effect of price on the decision to be a smoker, and on the amount of cigarettes smoked. Results: The overall price elasticity of cigarettes was estimated at -0.66, with a price elasticity of -0.02 for smoking participation and -0.64 for the amount of cigarettes consumed by smokers. The inclusion of other behavioral risk factors reduced the estimated price elasticity for smoking participation substantially, but had no effect on the conditional price elasticity for the quantity of cigarettes smoked. Conclusions: From the public health and financial perspectives, an increase in cigarette price would significantly reduce smoking prevalence as well as cigarette consumption by smokers in Korea.

• Journal of the Korea institute for structural maintenance and inspection
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• v.9 no.1
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• pp.101-111
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• 2005

In this study, it is investigated the modified modulus of elasticity of the reinforced concrete columns including the longitudinal reinforcing steels as well as the confinement effect of the core concrete due to the transverse reinforced steel through the literature reviews. Equations are derived in order to evaluate the modified modulus of elasticity for the reinforced compressive concrete including the confinement effect. The finite element analysis for the 20 story reinforced concrete building is undertaken as a case study depending on the steel ratio and modulus of elasticity, and the analysis results are discussed.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.30 no.3 s.47
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• pp.385-388
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• 2004

Recently, along with the remarkable increase in interest in natural products, the application of phytoestrogens in anti-aging products has become very important. In the focus, we developed Pueraria mirifica (PM), in this in vivo study on skin elasticity and wrinkles, and investigated the anti-aging properties. Thirty healthy women volunteers, between the ages of 30 and 60, applied the cream formula with $4\% Pueraria mirifica or placebo, on the face area twice a day for 16 weeks. The evaluation was made by silicon replica analysis, Cutometer SEM 575 and Comeometer followed by statistical treatment using the student's t-test. Results of skin elasticity measurement showed that topical application on the skin increased the total surface of skin elasticity in comparison with placebo group (p<0.05). However, PM cream does not have prominent effect on the depth of wrinkles and skin moisturization. This in vivo study demonstrates that, PM exhibits a significant effect on skin elasticity therefore, is of great interest in anti-aging and firmness skin care products.

• Structural Engineering and Mechanics
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• v.67 no.4
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• pp.417-425
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• 2018

The main aim of this paper is to investigate the bending of Euler-Bernouilli nano-beams made of bi-directional functionally graded materials (BDFGMs) using Eringen's non-local elasticity theory in the integral form with compare the differential form. To the best of the researchers' knowledge, in the literature, there is no study carried out into integral form of Eringen's non-local elasticity theory for bending analysis of BDFGM Euler-Bernoulli nano-beams with arbitrary functions. Material properties of nano-beam are assumed to change along the thickness and length directions according to arbitrary function. The approximate analytical solutions to the bending analysis of the BDFG nano-beam are derived by using the Rayleigh-Ritz method. The differential form of Eringen's non-local elasticity theory reveals with increasing size effect parameter, the flexibility of the nano-beam decreases, that this is unreasonable. This problem has been resolved in the integral form of the Eringen's model. For all boundary conditions, it is clearly seen that the integral form of Eringen's model predicts the softening effect of the non-local parameter as expected. Finally, the effects of changes of some important parameters such as material length scale, BDFG index on the values of deflection of nano-beam are studied.

• Journal of the Ergonomics Society of Korea
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• v.31 no.3
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• pp.455-461
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• 2012

The aim of this study was to investigate the appropriate elasticity of the textile material used for making women's girdle. Background: The elastic textiles have been used for making girdle. The hard type girdle gave high pressure on the body to make slim look. However, excessively high garment pressure caused negative effect to human bodies. This study studied the material giving proper garment pressure in girdle. Method: In this study five experimental girdles were made fabrics with various elasticities. The change of garment pressures and body girths were measured after subjects wearing the experimental girdles. The garment pressure was measured at 10 points. Body girths measured at abdomen, hip, and thigh. Results: The garment pressure of the commercial girdle was high at side of waistband, side femur and back gluteal fold. The experimental girdles made with high elasticity material definitely lowered garment pressure at those points. After wearing experimental girdle their abdomen and hip girths measurements were decreased. But, thigh girth was not reduced. Conclusion: The girdle made with excellent elasticity materials reduced garment pressure significantly and it made body slim as much as the commercial girdle except the thighs. Application: This study provides guideline for the developing girdle that applying optimum range of garment pressure with body slim effect.

• KSBB Journal
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• v.31 no.3
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• pp.178-185
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• 2016

Aging of the face is mainly related to the features that are sagging or loss of elasticity of the skin by reducing the volume around the eyes or cheek. Intrinsic aging can be seen to cause thinner dermis, reduction of extracellular matrix and subcutaneous fat. This study was carried out to investigate the skin volume augmentation and anti-wrinkle effects of Tribulus terrestris fruit extract. Skin anti-aging effect of Tribulus terrestris fruit extract was evaluated by using lipid accumulation, expressin of type I procollagen and elastin in preadipocytes and human dermal fibroblasts. Tribulus terrestris fruit extract augmented preadipocytes differentiation about 56% at 100 µg/mL. The type I procollagen and elastin were increased about 35% and 25% by treatment 20% Tribulus terrestris fruit extract, respectively. The clinical study also showed that skin sagging, skin elasticity, and dermal density improved without adverse effect following 4 week application of cream containing 2% Tribulus terrestris fruit extract. We suggest that Tribulus terrestris fruit extract can have the good possibility as skin volume augmenting, skin elasticity and wrinkle improving agent.

• Journal of the Korean Society of Clothing and Textiles
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• v.21 no.7
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• pp.1139-1152
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• 1997

Clothing consumption expenditure (UX) data of Korean consumers during the period of 1965 to 1993 were analyzed by time series analysis technique. According to the results of regression analysis, current income and UX of the year before showed most significant influences on the current UX. This means that the absolute and permanent income hypotheses can be accepted in case of clothing expenditures. However the effect of income decreased as the economy developed. The relative price of clothing had weak or no influence on clothing expenditures. It was also found out that CSX of the year before, the change of income, relative price of clothing ware the factors that affected clothing expenditures. From the estimation of Houthakker-Taylor state adjustment model, a negative stock coefficient was obtained. That is, clothing is subject to an inventor effect and Korean consumers regard clothing as one of the durable goods. To define whether clothing is a "luxury" or a "necessity", income and relative price elasticity of clothing expenditures were estimated. Income elasticity of clothing is slightly below 1.0 in case of national aggregate expenditures, and slightly above 1.0 in case of urban consumers' expenditures. Income elasticity has declined over time. Meanwhile the coefficient of price elasticity is not significant, indicating that the relative price of clothing have little connection with clothing expenditure.lothing expenditure.

• Advances in nano research
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• v.11 no.6
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• pp.607-620
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• 2021

In this paper, the vibrations of boron nitride nanotubes (BNNTs) are investigated by considering the electric field. To consider the size effect at nanoscale dimensions, the surface elasticity theory is exploited. The equations of motion of the BNNTs are obtained by applying Hamilton's principle, and the clamped-guided boundary conditions are also considered. The governing equations and boundary conditions are discretized using the differential quadrature method (DQM), and the natural frequency is obtained by using the eigenvalue problem solution. The results are compared with the molecular dynamic simulation in order to validate the accurate values of the surface effects. In the molecular dynamics (MD) simulation, the potential between boron and nitride atoms is considered as the Tersoff type. The Timoshenko beam model is adopted to model BNNT. The vibrations of two types of zigzag and armchair BNNTs are considered. In the result section, the effects of chirality, surface elasticity modulus, surface residual tension, surface density, electric field, length, and thickness of BNNT on natural frequency are investigated. According to the results, it should be noted that, as an efficient non-classical continuum mechanic approach, the surface elasticity theory can be used in scrutinizing the dynamic behavior of BNNTs.

• Structural Engineering and Mechanics
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• v.33 no.2
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• pp.193-213
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• 2009

In this paper structural analysis of nonhomogeneous nanotubes has been carried out using nonlocal elasticity theory. Governing differential equations of nonhomogeneous nanotubes are derived. Nanotubes include both single wall nanotube (SWNT) and double wall nanotube (DWNT). Nonlocal theory of elasticity has been employed to include the scale effect of the nanotubes. Nonlocal parameter, elastic modulus, density and diameter of the cross section are assumed to be functions of spatial coordinates. General Differential Quadrature (GDQ) method has been employed to solve the governing differential equations of the nanotubes. Various boundary conditions have been applied to the nanotubes. Present results considering nonlocal theory are in good agreement with the results available in the literature. Effect of variation of various geometrical and material parameters on the structural response of the nonhomogeneous nanotubes has been investigated. Present results of the nonhomogeneous nanotubes are useful in the design of the nanotubes.

• Journal of Preventive Medicine and Public Health
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• v.28 no.2 s.50
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• pp.450-461
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• 1995

This paper tested by using Micro TSP, an empirical econometric analysis to approve officially a hypothesis of price elasticity of the demand for medical care services in Korean national medical insurance and the economic effect of health care delivery system with time-series datas of Medical Insurance Statistical Yearbook$(1981\sim1993)$. The results suggest that the Korean medical insurance system shows moral hazard due to the change of coinsurance and the economic effect according to intervention of the health care delivery system, but it is different by insurers regardless of the same structure of the medical insurance scheme.