• Journal of Korean Society of Transportation
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• v.20 no.4
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• pp.95-107
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• 2002

Congestion and increasing returns to scale in the use of and in the provision of transportation facilities have been biggest challenges to policy makers. In order to counter these problems and thereby to promote economic efficiency, optimal congestion tax and marginal cost pricing are separately and strongly recommended for each case. In this paper, however, we show that they are valid only in Partial equilibrium context in which only the corresponding market is considered. We set up a formal general equilibrium model and prove that the recommended policies are not in general effective. We continue to give particular examples which show the invalidity of each policy and continue to show that in the same examples, there exist better but unconventional policies. Based on these findings we strongly suggest to employ quantify restricting policy measure or to find second-best pricing policies.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.37 no.6B
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• pp.453-463
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• 2012

The Effect of asymmetric interconnection charge is different between where the retail price of incumbent is regulated and that of incumbent is not regulated. When the retail price of incumbent is not regulated, the brand loyalty and the relative magnitude of each marginal cost determine the effect of consumer surplus. However, when the retail price of incombent is regulated, network substitution effect also plays a important role to the consumer surplus. The higher the brand loyalty, the lower the network substitution effect, or the higher the marginal cost of the entrant, the social welfare through the asymmetric interconnection charge is more increased. In the other cases, the consumer surplus might be decreased.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.16 no.2
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• pp.181-188
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• 2016

This paper demonstrates that centralized economic load dispatch optimization is much more economical than independent optimization carried out by individual power generating companies. The algorithm applied here optimizes by balancing the generation power at the valve-point, then readjusting generation power by comparing incremental operating cost incurred by marginal increase in the generation power and decremental operating cost likewise incurred by marginal decrease in the generation power. Upon comparing 3 individual optimization cases of 10, 13, and 40 generators respectively with centralized optimization of 63 generators, centralized operation for economic load dispatch optimization has proven to maximize economic benefits by markedly reducing operation costs of individual optimization.

• Quality Improvement in Health Care
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• v.7 no.2
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• pp.168-179
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• 2000

Background : Economic evaluation of clinical pharmacokinetic consultation services for theophylline, which is being widely used recently, is considered in patients for both proper care and cost efficiency. Mathods : This is a cost-benefit analysis of clinical pharmacokinetic consultation service for theophylline. Trial groups were chosen from 2 general hospitals which was performing clinical pharmacokinetic consultation- services in 1998. Control group was chosen from another one general hospital. The analysis includes 25 patients (sample patients) for trial group and 17 patients for control group. Results : On the basis of incremental analysis, it is estimated that the total (direct and indirect) annual costs of the clinical, pharmacokinetic services of theophylline for the patients in the trial group was about \65 million, whereas total annual benefits from those services was estimated to be about \551 million. The net benefits incurred to the sample patients, thus calculated, was about \485 million per year. In the analysis, we assumed that indirect benefits accruing to those services were non-existent. If that amount was included, the estimated net benefits would be much greater than the calculated one. Conclusion : We found that clinical pharmacokinetic consultation services for theophylline could produce more marginal benefits than marginal costs by those services from the social point of view. More controlled prospective trial in the future would be helpful for affirmation of the results of this study.

• Journal of Energy Engineering
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• v.5 no.1
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• pp.87-92
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• 1996

This paper formulates dynamic optimization model for Time-Of-Use Rates when a electric power system consists of three generators and a rating period is divided into three sub-periods. We use Pontryagin's Maximum Principle to derive optimal price and investment policy. Particularly the cross-price elasticities of demand are considered in the objective function. We get the following results. First, the price is equal to short-run marginal cost when the capacity is sufficient. However, if the capacity constraint is active, the capacity cost is included in the price. Therefore it is equal to the long-run marginal cost. Second, The length of rating period affects allocation of capacity cost for each price. Third, the capacity investment in dynamic optimization is proportional to the demand growth rate of electricity. However the scale of investment is affected by not only its own demand growth rate but also that of other rating period.

• Environmental and Resource Economics Review
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• v.18 no.4
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• pp.745-766
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• 2009

It is not valid to measure the degree of market power based on the markup of price over marginal market cost in an industry for which the market price of some inputs is not available because those inputs are then excluded in estimating the dual total cost function. If the roles of those inputs are ignored, the markup of price over marginal market cost is likely to be positive in the perfectly competitive industry. In order to have accurate market power markups for the environmentally regulated Korean iron and steel industry, in which the market price of raw material and the price of abatement capital are hard to obtain, in this paper, a dual cost function is derived given the optimal quantities of raw material and abatement capital, and then estimated jointly with the supply relation. The annual average degree of market power for the industry is estimated to be 0.49 over the period 1982~2001. Ignoring environmental regulation would overstate the degree of market power by about 8 percent.

• The Transactions of the Korean Institute of Electrical Engineers A
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• v.51 no.8
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• pp.379-384
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• 2002

In the competitive electricity market, various pricing methods are developed and practiced in many countries. Among these pricing methods, marginal loss factor(MLF) can be applied to reflect the marginal cost of network losses. For the calculation of MLF, power flow method has been used to calculate system loss deviation. However, this power flow method shows some shortcomings such as necessity of regional reference node, and absence of an ability to consider network constraints like line congestion, voltage limit, and generation output limit. The former defect might affects adversely to the equity of market participants and the latter might generate an inappropriate price signals to customers and generators. To overcome these defects, the utilization of optimal power flow(OPF) is suggested to get the system loss deviation in this paper. 30-bus system is used for the case study to compare the MLF results by the power flow and the OPF method for 24-hour dispatching and pricing, Generator payment and customer charge are compared with these two methods also. The results show that MLF by OPF reflects the power system condition more faithfully than that of by the conventional power flow method

• Proceedings of the KIEE Conference
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• 2005.07a
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• pp.751-753
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• 2005

In this raper, Economic value of reserve margin i.i presented by opportunity cost for Korean power system, and the level of compensation for spinning reserve that is necessary to operate power system stably is proposed. The generator that is giving up for opportunity to participate in energy market must take opportunity cost. it is relative to not only whole demand level but also marginal cost of each resource. In this paper, assume that all resource in Korea is equivalent to six generator for simulation. and we evaluate value of reserve in the time of high demand and low demand. Also we propose the way to improve a evaluation method by examine relationship between capacity payment and value of reserve.

• Korean Management Science Review
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• v.26 no.1
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• pp.21-35
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• 2009

There is a controversy on Internet pricing, flat-rate vs. usage-based. This study gives a comparative analysis between flat-rate and two-part tariff which is realistic alternative of usage-based pricing. In a basic economic model, two-part tariff based on ISP's cost structure satisfies allocative efficiency and relatively expand the number of subscribers. But the characteristics of Internet service like consumers' uncertainty on cost, measurement cost of traffic and network externality induce increase of cost or decrease of marginal utility. The analysis shows that small impact of these can make flat-rate more efficient.

• Journal of the Korean Society for Railway
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• v.11 no.3
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• pp.263-271
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• 2008

This article considers how the rail track charges of the advanced countries are performed and derived political implication to Korail. In case of North America and Japan, rail track charges are being decided to collect the infrastructure maintenance cost. In European countries, the separation of infrastructure and operation is realized and the railroad track charges are based on MC+ principle. On the other hand, Korail is paying construction cost of KTX as well as maintenance cost in Korea. As for this, railroad reform including rail track charging should be reconsidered.