• Journal of Korean Society on Water Environment
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• v.29 no.4
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• pp.476-488
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• 2013

Refractory Dissolved Organic Carbon (RDOC) is becoming more important index on management of water quality, water regulation as well as ecosystem management. We analyzed trends of RDOC using elasticity in the Nakdong river basin. If climate elasticity of streamflow is positive, change of streamflow can be defined by the proportional change in a climatic variable such as precipitation and temperature. Elasticity of streamflow to precipitation and elasticity of RDOC to precipitation were estimated in the present, and we also analyzed the variation of elasticity in the future using climate change scenarios, RCP 8.5/ 4.5. Mean streamflow elasticity is 1.655, and mean RDOC elasticity is 1.983. RDOC is more sensitive to precipitation change than streamflow. The variation of RDOC is directly proportion to precipitation in all scenarios, but the Load of RDOC is dependent on precipitation as well as others. There is a need for additional correlation analysis between RDOC and other factors for accurate prediction.

• Interaction and multiscale mechanics
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• v.1 no.3
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• pp.329-337
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• 2008

This paper presents the derivation of the generalized governing equations in theory of elasticity, their weak forms and the some applications in the numerical analysis of structural mechanics. Unlike the differential equations in classical elasticity theory, the generalized equations of the equilibrium and compatibility equations presented here take the form of integral equations, and the generalized equilibrium equations contain the classical differential equations and the boundary conditions in a single equation. By using appropriate test functions, the weak forms of these generalized governing equations can be established. It can be shown that various variational principles in structural analysis are merely the special cases of these weak forms of generalized governing equations in elasticity. The present weak forms of elasticity equations extend greatly the choices of the trial functions for approximate solutions in the numerical analysis of various engineering problems. Therefore, the weak forms of generalized governing equations in elasticity provide a powerful modeling tool in the computational structural mechanics.

• The Transactions of the Korean Institute of Electrical Engineers A
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• v.50 no.12
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• pp.568-574
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• 2001

The variations of real time electric power price in competitive electricity markets have influence on electric power demands of the consumers. The effects of the consumers for electric power price can be expressed the price elasticity coefficient of the power demand as a measurement. Residential, commercial, and industrial consumers with different characteristics cause the different price elasticity of the power demand due to changing the pattern of consumption. It is necessary that the effects of electric power demands as a function of elasticity coefficient for each loads should be analyzed in Korea which is processing deregulated electric market. Therefore, this paper calculate the elasticity coefficient of each loads and analysis the effects of electric power demands as a function of elasticity coefficient of inflexible and flexible consumers in competitive electricity market.

• Proceedings of the KSR Conference
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• 1999.11a
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• pp.209-217
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• 1999

A catenary system should be designed to be an uniform elasticity over a span in order to maintain the lowest possible loss of contact between a pantograph and a contact wire. A elasticity disuniformity of a catenary can be regarded as a important design factor used for predicting the current collection performance for a catenary. There are a couple of formulas to calculate elasticity disuniformity of a catenary according to the literature survey, The effectiveness of these formulas is reviewed by performing catenary elasticity and loss of contact analysis for 5 different configurations of catenary systems using a beam element based FEM program, KRRI developed program, and the loss of contact by GASENDO, RTRI developed program, respective]y. The results reveals that these formulas are not suitable to predict the current collection performance for a catenary. Therefore, a new formula based on the standard deviation of the elasticity over a span is proposed in this study. The analysis results show that the new formula for an elasticity disuniformity of a catenary is very effective in predicting the current collection performance for a catenary.

• 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 Physiology & Pathology in Korean Medicine
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• v.25 no.6
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• pp.1050-1055
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• 2011

This paper presents a novel diagnostic method to determine Sasang Consitution (SC) by elasticity coefficient of hand dorsal skin of elderly people. For this purpose, we carried out a clinical test, in which Our SC diagnostic tool and one Oriental medical doctor with SC medicine expertise participated to categorize 458 healthy subjects into four constitutions. After excluding heavy-noise, we extracted 295 subjects' elasticity coefficient feature data and statistically analyzed their SC relevance with ANOVA test. It resulted in that, Taeum-in has high elasticity coefficient compared to Soeum-in in a significance level of 0.05. There are no differences of elasticity coefficient in genders. This result is supported by the theory of Longevity and Life Preservation in Eastern Medicine(Donguisusebowon, 동의수세보원) which suggested that Taeum-in's flesh is solid and Soeum-in's one is tender. This is the first work which reports the relatedness of skin elasticity coefficient and SC by an objective clinical test.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.15 no.1
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• pp.72-80
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• 2014

This study is to estimate a demand of coffee in Korea. And based on assumed data, this study is to investigate price elasticity, income elasticity and cross-price elasticity of coffee demand. The data used in this study is the household income and expenditure survey micro data (2003~2012) provided by the National Statistical Office. And LA/AIDS model and SUR method were utilized in order to forecast coffee demand. As a result, price elasticity and income elasticity are found to be correspond with economic theory as they were assumed to -0.259, 0.455 respectively. Meanwhile, it indicated characteristic of essential good by showing negative (-) income odds ratio estimate. When it comes to cross-price elasticity of coffee and cigarette, it was found to be a complementary relation as its cross-price elasticity was assumed to -0.121. Besides, it was found that male consume more coffee than female, while people in their age of 50s consumes mostly. In conclusion, this study suggests necessity of reconsidering coffee as important goods when Consumer Price Stabilization Policy is determined, as coffee shows characteristic of essential goods which is inelastic.

• Journal of the Korea Concrete Institute
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• v.12 no.6
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• pp.35-42
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• 2000

In paper I, the relationships between compressive strength and splitting tensile strength or modulus of elasticity were proposed. In this paper, new prediction model is investigated from estimating splitting tensile strength and modulus of elasticity with curing temperature and aging without compressive strength. New prediction model is based on the model which was proposed to predict compressive strength, and splitting tensile strength and modulus of elasticity calculated by this model are compared with experimental values of paper I. To evaluate in-situ applicability of the model, strength and modulus of elasticity tested with variable temperatures are estimated by the prediction model. The prediction model reasonably estimates the strength and the modulus of elasticity of type I and V cement concretes tested in paper I and experimental results with variable temperature tested in this paper.

• Journal of the Korean Home Economics Association
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• v.40 no.7
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• pp.101-118
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• 2002

This study examined the levels and trends in the household expenditure in both public and private education. Between 1982 and 2000, the level of the total educational expenditure increased by 5% in each year on average, increased by 2.2% for public education, and by 11.4% for private education. On the public educational expenditure, the consumption expenditure elasticity was 0.2 and the price elasticity was 1.49. On the private educational expenditure, the consumption expenditure elasticity was 1.5 and became below 1 after 1998, and the price elasticity was 2.63. The results indicated that the educational expenditure was necessary rather than luxurious and there was excess demand for private education. The level of the educational expenditure would continue to increase without reforms both in the supply and demand sides.

• Journal of the Korean Wood Science and Technology
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• v.39 no.5
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• pp.398-405
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• 2011

Nondestructive evaluation (NDE) technique method using a resonance frequency mode was carried out for woodceramics made by different phenol resin impregnation ratios (40, 50, 60, 70%) for Broussonetia Kazinoki Sieb. Dynamic modulus of elasticity increased with increasing resin impregnation ratios. There was a close relationship between dynamic modulus of elasticity and static bending modulus of elasticity and between dynamic modulus of elasticity and MOR and between static bending modulus of elasticity and MOR. Therefore, the dynamic modulus of elasticity using resonance frequency mode is useful as a nondestructive evaluation method for predicting the MOR of woodceramics made by different impregnation ratios.