• Proceedings of the KIEE Conference
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• 2009.07a
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• pp.1165_1166
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• 2009

In recent years, energy prices have soared, which of course have increased costs for railway operators. Simultaneously, the energy market has considerably changed that in most developed countries, it is deregulated, giving railway operators an opportunity to define new ways of using energy. Efficient operation of the railway system is considered as an essential way to energy saving while an efficient management of power level helps to lower the reference subscribed power, giving access to better energy rates. It is studied on the relation between time and force for the energy efficient driving of train in railway when the train is braking according to several slips.

• Management Science and Financial Engineering
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• v.10 no.2
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• pp.53-71
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• 2004

In this study, a mathematical model that shows the optimal payout policy is developed. The model is new and unique in the sense that not only continuous-time framework is used, but also both partial differential equation (PDE) and real-option approach are utilized in the derivation of optimal payouts for the first time. In the model building, non-linear demand curve for dividend payouts in the competitive capital markets is assumed. From the sensitivity analysis using traditional comparative static analysis, some useful managerial implications which are consistent with famous previous studies are derived under realistic conditions. All results in this study, however, are valid under the assumption that the opportunity costs follow geometric Brownian motion, which is widely used in economic science and finance literature.

• Proceedings of the Korea Water Resources Association Conference
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• 2008.05a
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• pp.9-18
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• 2008

The fundamental objects of the Korean Grand Canal (KGC) Project are the rehabilitation(or restoration) of river corridor ecology, improvement of river water quality, reduction of flood damages, countermeasure of the huge rise in energy price and the high discharge of $CO_2$ due to the vast use of energy for highway logistics. The other important objects, like an increase of water in the river channel, are to provide people with the pleasure of seeing the water and intimacy (touchiness) with it, an increase of flood controllability, effects of dilution of river pollutants, dredging out sedimentary pollutant from the river bottom, the function of infrastructure to pare down the logistics (distribution) costs, and the opportunity to expand tourism. These kinds of fundamental concepts must be evaluated as future values in Korea and elsewhere.

• Asian-Australasian Journal of Animal Sciences
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• v.20 no.3
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• pp.453-460
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• 2007

An overview of developments important in the future of animal breeding is discussed. Examples from the application of quantitative genetic principles to selection in chickens and mice are given. Lessons to be learned from these species are that selection for production traits in livestock must also consider selection for reproduction and other fitness-related traits and inbreeding should be minimized. Short-term selection benefits of best linear unbiased predictor methodology must be weighed against long-term risks of increased rate of inbreeding. Different options have been developed to minimize inbreeding rates while maximizing selection response. Development of molecular genetic methods to search for quantitative trait loci provides the opportunity for incorporating marker-assisted selection and introgression as new tools for increasing efficiency of genetic improvement. Theoretical and computer simulation studies indicate that these methods hold great promise once genotyping costs are reduced to make the technology economically feasible. Cloning and transgenesis are not likely to contribute significantly to genetic improvement of livestock production in the near future.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.57 no.7
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• pp.1157-1166
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• 2008

This paper presents a new approach for the evaluation of location marginal prices (LMPs) considering demand-side bidding (DSB) in a competitive electricity market. The stabilization of the electric power supply and demand balance is one of the major important activities in electric power industry. In this paper, we present an analytical method for calculation of LMPs considering DSB, which has opportunity to compete with generating units, as England & Wales Pool's DSB scheme[1]. Also, we propose a new approach that LMP considering DSB is divided into three components. The proposed approach can be used for the evaluation of demand-side bidding into the electricity market and the assessment of the influence of DSB on total production costs and LMPs as well as three components.

• Proceedings of the KIEE Conference
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• 1999.11b
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• pp.181-183
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• 1999

As one of ancillary services, voltage support and reactive power service should be compensed properly for its contribution. In this paper, a cost-based reactive power planning is presented. which minimizes the total cost of reactive power support of generators and VAR compensation facility installation. Reactive power support of generator is evaluated by the opportunity costs of reduced energy sale considering the varying SMP(system marginal price) in power market, Gradient projection method is applied to solve this reactive power planning using IEEE14 bus system.

• Transactions of the Korean Society of Pressure Vessels and Piping
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• v.8 no.2
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• pp.33-41
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• 2012

The component cooling water heat exchangers are critical components in a nuclear power plant. As the operation years of the heat exchanger go by, the maintenance costs required for continuous operation also increase. Most heat exchangers have carbon steel shells, tube support plates and flow baffles. The titanium tube is susceptible to flow induced vibration. The damage on carbon steel tube support rod and titanium tube around cooling water entrance area is inevitable. Therefore, analysis of internal flow around the component cooling water entrance and tube channel is a good opportunity to seek for failure prevention practice and maintenance method. The numerical study was carried out by FLUENT code to find out the causes of tube failure and its location.

• Journal of the Korean Regional Science Association
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• v.15 no.2
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• pp.103-116
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• 1999

As Asia becomes increasingly integrated economically, opportunity particularly in managing financial flows, as bases to coordinate regional production networks, and as staging points for the penetration of new markets. The paper argues for a path-dependent logic to understanding the efforts of the Singapore State in hosting hub functions. As a city-state without a national economic hinterland, Singapore's response to increasing business costs and regional competition has been to create a set of policies designed to encourage multinational companies to keep administrative control functions in Singapore while moving the more labour and land intensive production functions to nearby Malaysia and Indonesia. An understanding of the competition among cities in the Asia Pacific for hub functions must also take into account corporate strategy within particular industry dynamics. The second half of the paper provides a number of case studies to show this interplay between corporate strategy, industry dynamic and government policy.

• Transactions of the Korean Society of Automotive Engineers
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• v.10 no.2
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• pp.174-185
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• 2002

The automotive industry faces many competitive challenges including weight and cost reduction to meet need for higher fuel economy. Tailored blanks offer the opportunity to decrease door weight, reduce manufacturing costs, and improve door stiffness. Optimization technology is applied to the inner panel of a door which is made by tailored blanks. The design of tailored blanks door starts from an existing door. At first, the hinge reinforcement and inner reinforcement are removed to use tailored blanks technology. The number of parts and the welding lines are determined from intuitions and the structural analysis results of the existing door. Size optimization is carried out to find thickness while the stiffness constraints are satisfied. The door hinge system is optimized using design of experiment approach. A commercial optimization software MSC/NASTRAN is utilized for the structural analysis and the optimization processes.

• Environmental and Resource Economics Review
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• v.16 no.3
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• pp.607-627
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• 2007

By reviewing the current application of Environmental Fiscal Instruments in China, existing policy gaps and weakness, and the feasibility of using EFIs in China, this paper pointed out that the Chinese government faces an historic opportunity for promoting the development of a comprehensive environmental fiscal system. It is proposed that as far as possible the real economic and social costs of pollution and environmental degradation should be reflected in the prices charged for the use of environmental and natural resources. Chinese government should systematize existing environmental fiscal funds and policies, gradually setting up a framework for integrating environmental fiscal instruments into the public financial system.