• Journal of Korean Society of Transportation
• /
• v.25 no.4
• /
• pp.99-108
• /
• 2007

This paper presents an elastic demand stochastic user equilibrium traffic assignment that could not be easily tackled. The elastic demand coupled with a travel performance function is known to converge to a supply-demand equilibrium, where a stochastic user equilibrium (SUE) is obtained. SUE is the state in which all equivalent path costs are equal, and thus no user can reduce his perceived travel cost. The elastic demand SUE traffic assignment can be formulated based on a dynamic system, which is a means of describing how one state develops into another state over the course of time. Traditionally it has been used for control engineering, but it is also useful for transportation problems in that it can describe time-variant traffic movements. Through the Lyapunov Function Theorem, the author proves that the model has a stable solution and confirms it with a numerical example.

• International Area Studies Review
• /
• v.14 no.1
• /
• pp.279-298
• /
• 2010

This paper investigates the characteristics of Korean international tourism demand for selected 13 destination countries by estimating income and travel price elasticities using quarterly data from 1990:1 to 2006:2. Major findings of this paper could be summarized as follows. First, long-run equilibrium relationships between Korean international tourism demand for 13 destination countries, real income and travel price variables are confirmed. Second, the estimated income elasticities of Korean tourism demand for 13 destination countries are all elastic; especially, those for Australia, Philippine, Thailand and China are very elastic. And their estimated values vary with destination countries, which implies the income effects for 13 destination countries are all different; however there is no evidence that the income effects could be characterized by traveling distances. Third, the estimated travel price elasticities of Korean tourism demand for 13 destination countries also differ from destination countries; in most cases, they are elastic except those for Hong Kong and United States. The most travel price elastic countries are Canada, Australia and New Zealand.

• Earthquakes and Structures
• /
• v.13 no.4
• /
• pp.337-351
• /
• 2017

In the present study a capacity spectrum method based on constant ductility inelastic spectra to estimate the seismic performance of structures equipped with elastic viscous dampers is presented. As the definition of the structures' effective damping, due to the damping system, is necessary, an alternative method to specify the effective damping ratio ${\xi}eff$ is presented. Moreover, damping reduction factors (B) are introduced to generate high damping elastic demand spectra. Given the elastic spectra for damping ratio ${\xi}eff$, the performance point of the structure can be obtained by relationships that relate the strength demand reduction factor (R) with the ductility demand factor (${\mu}$). As such expressions that link the above quantities, known as R - ${\mu}$ - Τ relationships, for different damping levels are presented. Moreover, corrective factors (Bv) for the pseudo-velocity spectra calculation are reported for different levels of damping and ductility in order to calculate with accuracy the values of the viscous dampers velocities. Finally, to evaluate the results of the proposed method, the whole process is applied to a four-storey reinforced concrete frame structure and to a six-storey steel structure, both equipped with elastic viscous dampers.

• The Journal of The Korea Institute of Intelligent Transport Systems
• /
• v.8 no.2
• /
• pp.1-13
• /
• 2009

Although enormous data have been collected in major cities (Korea) by APTS(Advanced Public Transit Systems), most of studies related to bus schedule management evaluation have confined to headway adherence and on-time performance. Therefore, bus operation management have been very lack of using APTS data. This study uses coefficient of correlation to evaluate bus company's schedule management level. However, direct application of coefficient of correlation has inequitable problem because of many limitation(number of vehicle, headway, etc). and so variable calibration method was developed and applied to cope with these problems. Thus, demand-elastic management evaluation index was developed. For verifying the equity of developed index, it is applied to Seoul bus routes. It is expected for the developed index to contribute into the demand-elastic management of bus schedule.

• Korea journal of population studies
• /
• v.25 no.2
• /
• pp.271-291
• /
• 2002

According to a system-wide analysis utilizing the raw data of Korean urban households survey, the expenditure elasticity estimate of alcoholic demand is around 0.71, which implies the demand for alcoholic consumption is relatively necessary The own price elasticity estimates are pretty elastic between -1.79 and 2.10. The trend of price elasticity estimates shows to be more elastic recently from the past.

• Journal of the Korean Society of Clothing and Textiles
• /
• v.38 no.1
• /
• pp.33-45
• /
• 2014

This study investigates urban household consumption patterns for clothing items in different income cohorts through the analysis of an Almost Ideal Demand System (AIDS) model. Korea quarterly time-series statistics data for urban household expenditures from 1990 to 2013 analyzed household demand. The price and total consumption expenditure elasticities of 4 clothing items (outer wear, shoes, clothing related services and other miscellaneous clothing) for 7 income cohorts were estimated to investigate the clothing consumption patterns of different income cohorts. The study results show that the different household income cohorts have different consumption patterns for clothing items. The elastic demand of total consumption expenditures in the lowest household income cohort suggests that they consume clothing items as luxuries while other households mostly consume them as necessities. The price elasticity for all household income cohorts and clothing items (except the highest household income cohort and outer wear) was found to be elastic. The highest household income cohort had an inelastic price demand for all clothing items that implied a less sensitive clothing consumption change for the clothing price change than other households.

• Journal of Energy Engineering
• /
• v.25 no.2
• /
• pp.37-44
• /
• 2016

The demand for electricity has a considerable impact on various energy sectors since electricity is generated from various energy sources. This paper attempts to estimate the electricity demand function and obtain some quantitative information on price and income elasticities of the demand. To this end, we apply a lagged dependent variable model to derive long-run as well as short-run elasticities using the time-series data over the period 1991-2014. Our dependent variable is annual electricity demand. The independent variables include constant term, real price of electricity, and real gross domestic product. The results show that the short-run price and income elasticities of the electricity demand are estimated to be -0.142 and 0.866, respectively. They are statistically significant at the 5% level. That is, the electricity demand is in-elastic with respect to price and income changes in the short-run. The long-run price and income elasticities of the electricity demand are calculated to be -0.210 and 1.287, respectively, which are also statistically meaningful at the 5% level. The electricity demand is still in-elastic with regard to price change in the long-run. However, the electricity demand is elastic regarding income change in the long-run. Therefore, this indicates that the effect of demand-side management policy through price-control is restrictive in both the short- and long-run. The growth in electricity demand following income growth is expected to be more remarkable in the long-run than in the short-run.

• The Journal of Fisheries Business Administration
• /
• v.43 no.1
• /
• pp.35-48
• /
• 2012

Inverse demand models are well established as market demands in theory and practice of the existing literature. However, the derivation and its interpretation of individual demands from the market demands are not well known in the literature. This paper analyzes the fish market in Korea by the inverse demand model and shows how we deduce the consumer's responses from the market responses when the markets determine the prices by the quantities demanded. It illustrates empirically how this can be done applying to the korean fish market data. The empirical results show that all fishes are price inflexible and mackerels and hairtails are scale flexible in the market demand while mackerels, hairtails, and croakers are price elastic and mackerels and hairtails are income inelastic in the individual demand. The methodology and empirics used in the paper will make a contribution to the existing literature especially for the purpose of recovering consumer's demand from the market demand, thus implementing the policies to administer the fish markets.

• Environmental and Resource Economics Review
• /
• v.11 no.1
• /
• pp.81-97
• /
• 2002

Unlike the existing supply-centered water policy, demand management policy of water has become an increasingly important issue in Korea. This paper attempts to analyse the demand for domestic water in Seoul. We employed Engle-Granger's error correction model(ECM) to deduced the price and income elasticities of the water demand. Particularly, we used accounted water amounts instead of supplied water amounts as representative variable of water demand. The result indicates that ECM set up is appropriate and short-run and long-run price elasticities derived by the model are -0.145 and -1.414. In contrast with other studies, we can conclude that the water demand for the water price is elastic. Besides, we can infer from this result that the water price policy with respect to a decrease of leakage ratio is more effective.

• Journal of Korean Society of Transportation
• /
• v.26 no.1
• /
• pp.51-63
• /
• 2008

Jeju-Mainland demand for air passenger is variated by the season because most of the demands stem from the leisure travel. This research is to estimate the econometrics demand models(A simple time series model and the partial adjustment model) and elasticities of each models for the Jeju-Mainland domestic routes air travel market using the time series aggregate data between the year 1996 and 2005. As the result of estimating, income elasticity was evaluated to be elastic(1.55) and fare elasticity was inelastic(-0.49${\sim}$-0.59) for A simple time series models. In the partial adjustment model's case, income elasticity was evaluated to be inelastic(0.51) in short-run whereas it was evaluated to be elastic(1.88) in long-run. Fare elasticity was evaluated to be inelastic in short-run(high-demand season: -0.13, slack season: -0.20) and long-run(high-demand season: -0.48, slack season: -0.72).