• 산업공학
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• 제9권3호
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• pp.44-51
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• 1996

The purpose of this paper is to develop a modeling framework for analyzing the effect of price on the PCS (Personal Commununications Service) demand. To achieve this aim, a nonlinear regression model was derived to capture the income effect on the PCS demand and then was combined into an integrated Bass diffusion model. The model was then applied to the emerging PCS market in Korea and the market demands up to the year 2006 were estimated. The results were reviewed and evaluated in various aspects. Finally, the possibilities of model enhancement and model extensions were explored.

• 한국생산제조학회지
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• 제6권1호
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• pp.109-114
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• 1997

In the past few decades, the measuring instrument industries have made rapid progress with increase on the demand in industries such as precision instrument, chemistry, electronics, industrial measurement and automobile. Thus, development strategy and technical advancement are required for both securing the competitiveness on products in the world market and industrial development. Intensifying competitiveness of measuring instrument is needed in the world market. It can be achieved by development of measuring instrument holding comparative priority. A development strategy should be drawn up in the long-term point of view for coping with the increasing demand of measuring instrument and securing competitiveness in the world market.

• Journal of applied mathematics & informatics
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• 제6권2호
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• pp.539-552
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• 1999

An order-level inventory model for a perishable product with a time-dependent demand is developed for a fixed planning pe-riod allowing backlogging in all cycles within the said period. The market demand is assumed to decrease exponentially as time elapses. The average system cost is derived and its optimization procedure is illustrated with a numerical example. Sensitivity of the optimal so-lution to changes in the values of different parameters of the system is also analysed.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2009년도 춘계학술대회 논문집
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• pp.1708-1727
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• 2009

Even though we usually analyze logistic market based on confined railway logistics, but this study would like to judge what is potential demand transferable to railway goods through accurate analysis of railway sharing rates by the analysis of origin and destination of each item in total freight transportation market. Accordingly, by analyzing each items transferable to railway, excluding items stuck to original market, this study wants to choose some major items which are expected to lasting demand and activate railway logistics plan by focusing on major items for marketing strategy.

• 전기학회논문지
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• 제57권1호
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• pp.20-24
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• 2008

A bid-based pool(BBP) model is representative of energy market structure in a number of restructured electricity markets. Supply function equilibrium(SFE) models of interaction better match what is explicitly required in the bid formats of typical BBP markets. Many of the results in the SFE literature involve restrictive parametrization of the bid cost functions. In the SFE models, two parameters, intercept and slope, are available for strategic bidding. This paper addresses the realistic competition format that players can choose both parameters arbitrarily. In a fixed demand function, equilibrium conditions for generation company's profit maximization have a degree of freedom, which induces multi-equilibrium. So it is hard to choose a convergent equilibrium. However, consideration of stochastic demand function makes the equilibrium conditions independent each other based on the amount of variance of stochastic demand function. This variance provides the bidding players with incentives to change the slope parameter from an equilibrium for a fixed demand function until the slope parameter equilibrium.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2002년도 추계학술대회 논문집 전력기술부문
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• pp.384-386
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• 2002

As restructuring in power industry has introduced competitive markets, a new method on demand side management has been developed. Many programs using the method were developed with providing several choices for customer. Nowadays the programs are called demand response as the load management is done by customer's responding to the market price signal. It was proven that the method was effective for demand control with the active consumer's attending for the program. This paper analyses the perspective and the requirement for designing the demand response system.

• Journal of Information Technology Applications and Management
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• 제24권2호
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• pp.81-96
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• 2017

Forecasting long-term mobile service demand is inevitable to establish an effective frequency management policy despite the lack of reliability of forecast results. The statistical forecasting method has limitations in analyzing how the forecasting result changes when the scenario for various drivers such as consumer usage pattern or market structure for mobile communication service is changed. In this study, we propose a dynamic model of the mobile communication service market using system dynamics technique and forecast the future demand for long-term mobile communication subscriber based on the dynamic model, and also experiment on the change pattern of subscriber demand under various scenarios.

• 한국정보통신학회논문지
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• 제22권9호
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• pp.1191-1198
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• 2018

본 논문에서는 온디맨드 비디오 스트리밍 플랫폼에 대한 콘텐츠 쿼터제 적용의 실효성 확보 방안에 관하여 분석하였다. 특히 넷플릭스(Netflix)의 EU시장 진출에 대한 공동체의 대응을 중심으로 단일시장 내 저작권 보호 및 문화산업 보호에 관한 OTT 규제의 효과성을 분석하였다. 온디맨드 비디오 스트리밍 서비스와 넷플릭스의 성장 그리고 넷플릭스의 EU 시장 진출에 대해 고찰하고 있다. 다음으로 EU 내 온디맨드 비디오 스트리밍 서비스 현황을 분석한다. 온디맨드 비디오 스트리밍 서비스 시장 대응에 관한 EU의 정책은 디지털 단일 시장 내 '이동성(portability)' 그리고 저작권 보호를 위한 콘텐츠 쿼터제 등으로 구성되며, OTT 규제의 세부지침의 고찰을 통해 시장보호 그리고 온라인 스트리밍 서비스업의 경쟁력 제고 방안 측면을 분석하였다. EU는 유럽 방송사업자에게만 적용되어 온 콘텐츠 쿼터제를 OTT 사업에 적용, 규제함으로써 역내 문화산업 보호 및 저작권 보호 강화를 도모하고 있다.

• 한국항해학회지
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• 제4권2호
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• pp.45-79
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• 1980

The aim of this paper is to analyze the mechanics of price formation in the tramp shipping. For the purpose of this study, the main characteristics of tramp freight rates and the market is examined, and a brief examination of the nature ofthe costs of operation is given which are essential for the understanding of the functioning of shipping firms as well as for the understanding of developments in the tramp freight market. The demand and supply relationships in the market is also analysed in detail. Tramp shipping is an industry that has a market which functions under conditions that are not dissimilar to the theoretical model of perfect competition. However, it does notmean that tramp shipping market is a perfectly competitive market. It is apparent that this realworld competitive system has its imperfections, which means that the market for tramp shipping is near to being a perfectly competitive market on an internaitonal scale and it is freight are therefore subjext to the laws of supply and demand. In theory, the minimum freight rate in the short term is that at which the lowest cost vessels will lay-up in preference to operating, and is equal to the variable costs minus lay-up costs; and this would imply that in all times except those of full employment for ships there is a tendency for newer low-cost, and, probably, faster vessels to be driving the older high-cost vessels in the breaker's yards. In this case, shipowners may be reluctant to lay-up their ships becasue of obligations to crews, or because they would lose credibility with shippers or financiers, or simply because of lost prestige. Mainly, however, the decision is made on strictly economic grounds. When, for example, the total operating costs minus the likely freight earnings are greater than the cost of taking the ship out of service, maintaining it, and recommissioning it, then a ship may be considered for laying-up; shipowners will, in other words, run the ships at freight earnings below operating costs by as much as the cost of laying them up. As described above, the freight rates fixed on the tramp shipping market are subject to the laws of supply and demand. In other words, the basic properties of supply and demand are of significance so far as price or rate fluctuations in the tramp freight market are concerned. In connection with the same of the demand for tramp shipping services, the following points should be brone in mind: (a) That the magnitude of demand for sea transport of dry cargoes in general and for tramp shipping services in particular is increasing in the long run. (b) That owning to external factors, the demand for tramp shipping services is capable of varying sharphy at a given going of time. (c) The demad for the industry's services tends to be price inelastic in the short run. On the other hand the demand for the services offered by the individual shipping firm tends as a rule to be infinitely price elastic. In the meantime, the properties of the supply of the tramp shipping facilities are that it cannot expand or contract in the short run. Also, that in the long run there is a time-lag between entrepreneurs' decision to expand their fleets and the actual time of delivery of the new vessels. Thus, supply is inelastic and not capable of responding to demand and price changes at a given period of time. In conclusion, it can be safely stated that short-run changes in freight rates are a direct result of variations in the magnitude of demand for tramp shipping facilities, whilest the average level of freight rates is brought down to relatively low levels over prolonged periods of time.

• 한국수소및신에너지학회논문집
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• 제17권1호
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• pp.90-97
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• 2006

Hydrogen is used as a chemical feedstock in several important industrial processes, including oil refineries and petro-chemical production. But, nowadays hydrogen is focused as energy carrier on the rising of problems such as exhaustion of fossil fuel and environmental pollution. Thermochemical hydrogen production by nuclear energy has potential to efficiently produce large quantities of hydrogen without producing greenhouse gases, and research of nuclear hydrogen, therefore, has been worked with goal to demonstrate commercial production in 2020. The oil refineries and petro-chemical plant are very large, centralized producers and users of industrial hydrogen, and high-potential early market for hydrogen produced by nuclear energy. Therefore, it is essential to investigate and analyze for state of domestic hydrogen market focused on industrial users. Hydrogen market of petro-chemical industry as demand site was investigated and worked for demand forecast of hydrogen in 2020. Also we suggested possible supply plans of nuclear hydrogen considered regional characteristics and then it can be provided basis for determination of optimal capacity of nuclear hydrogen plant in 2020.