• The Transactions of the Korean Institute of Electrical Engineers A
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• v.50 no.2
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• pp.58-66
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• 2001

This paper presents an application of a newly designed Adaptive Genetic Algorithm (AGA) to solve the Optimal Feeder Routing (OFR) problem for distribution system planning. The main objective of the OFR problem usually is to minimize the total cost that is the sum of investment costs and system operation costs. We propose a properly designed AGA, in this paper, which can handle the horizon-year expansion planning problem of power distribution network in which the location of substation candidates, the location and amount of forecasted demands are given. In the proposed AGA, we applied adaptive operators using specially designed adaptive probabilities. we also a Simplified Load Flow (SLF) technique for radial networks to improve a searching efficiency of AGA. The proposed algorithm has been evaluated with the practical 32, 69 bus test system to show favorable performance. It is also shown that the proposed method for the OFR can also be used for the network reconfiguration problem in distribution system.

• Proceedings of the KSR Conference
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• 2009.05a
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• pp.822-827
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• 2009

Recently, a large amount of budget was invested in improving the railway tracks(double tracking, route improvement) of Janghang and Jungang line. However, further action to enhance the investment effect has been needed because the desired effect have not been obtained. This study was designed to evaluate the effect of track improvement briefly by examining the project summary of Janghang and Jungang line railway line improvement and analysing the change of the transport performance and revenue. The results of this study can be applied not only to establish an operation plan for maximizing the revenue of rail operation also to enhance an effect of track improvement.

• Environmental and Resource Economics Review
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• v.11 no.4
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• pp.633-657
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• 2002

This study presents a demand modelling for landfill gas, which is used as alternative energy source for district cooling business. By analyzing the cost minimizing behavior of producer facing with three alternative energy sources such as electricity, cooling heat water, and gas, a demand function for landfill gas is derived from the optimal operating time of gas fired production facility, and estimated using unpublished data, which are associated with Seoul city's development plan for Sang-am area. The estimation results repeals that Seoul City could supply the land-fill gas of 13.76 million cubic meters each year at the price of about 16 won per cubic meters. However, if the investment costs associated with installation of gas collecting facilities are treated as sunk costs, annual amount of gas supplied is expected to increase to 14.22 million cubic meters at a lower unit price of 14.76 won.

• Journal of the Korean Professional Engineers Association
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• v.45 no.5
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• pp.26-35
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• 2012

Korea is now the 12th largest economy in the world, surpassing its annual trade in the amount of $1 trillion, and it has joined the socalled 20-50 Club, becoming one of the seven countries in the world with capita income of more than $20,000 with population of 50 million. However it ranked 24th of the Global competitiveness index evaluated by World Economic Forum based on the basic requirements including infrastructures, efficiency enhances, innovation and sophistication factors, etc. The extensive and efficient SOC infrastructures are critical for ensuring the global competitiveness of each country. Effective modes of SOC facilities including quality roads, railroads, ports, air transport, etc will be able to reduce the annual traffic congestion cost as well as macro economic logistics costs in Korea, thereby the global competitiveness can be strengthened in the global market.

• Proceedings of the KIEE Conference
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• 2003.07a
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• pp.77-79
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• 2003

New cities and industrial complexes are being developed actively because of the government policies aiming population distribution and vitalization of construction industry. To determine the investment amount, number of power lines and substations for stable power supply to newly developed residential and industrial complexes, accurate estimation of power demand is necessary. This paper propose standards for the estimation of power demands for power company and construction company to settle the debates surrounding this issue. Through a survey and analysis of existing areas, new standards that will enable more accurate estimation of power demands in new cities complexes to be developed in the future are established by calculating the average load density, load factor, utilization factor by area, use and building size after dividing the facilities into building type and the areas into the areas planned to be developed and the areas not yet planned to be developed.

• Journal of the Korean Society for Aviation and Aeronautics
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• v.13 no.3
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• pp.117-128
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• 2005

Since terrorist attacks on the United States in 9/11, the aviation terror has been rapidly reduced while having an enormous amount of expenses invested in the aviation terror prevention. The aviation terror indicates itself the problem, and by the same token, the aviation terror prevention requires a huge investment. However, the available resources are limited, which raises concern over the effective use of the limited resources. Therefore, in order to contribute to the establishment of effective aviation security measures, this study examines and analyses the aviation terror types and changes, with the forecast of the aviation terror types with high occurrence potentiality, and suggests the countermeasures for the aviation terror prevention.

• Korea Journal of Hospital Management
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• v.4 no.2
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• pp.305-329
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• 1999

Financial ratio indicators of the 46 sample hospitals provided by the Korea Health Industry Development Institute, together with the survey data responded by the 57 sample hospitals, were analysed to identify the characteristics of the red-figured hospitals' financial structure, financial operational efficiency and management decision-making behavior, The financial characteristics identified through the analysis include high dependency to liabilities, high salary expenses and overhead costs, low profitability of the unduly large amount of fixed assets, and low managerial efficieny of inventory. The hospitals, in face of the IMF economic impasse, took the necessary decision-making and counter measures to cut down salary expenses, to increase the number of patient and medical revenue, and to reduce investment to fixed assets. Based on these findings this study suggested that the hospitals should take more active cost containment measures, financial structural reorganization, and developoment of the strategies that can contribute to increase of the number of patient and medical revenue and that do not. require much capital funds.

• Journal of KIBIM
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• v.6 no.3
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• pp.24-33
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• 2016

Planning occurs from day-to-day, small-scale decisions to large-scale infrastructure investment decisions. For that reason, various attempts have been made to appropriately assist decision-making process and its optimization. Lately, initiation of a large amount of data, also known as big data has received great attention from diverse disciplines because of versatility and adoptability in its use and possibility to generate new information. Accordingly, implementation of big data and other information management systems, such as geographic information systems (GIS) and building information modeling (BIM) have received enough attention to establish each of its own profession and other associated activities. In this extent, this study illustrates a series of big data implementation cases that can provide a lesson to urban planning domain. In specific, case studies analyze how data was used to extract the most optimized solution and what aspects could be helpful in relation to planning decisions. Also, important notions about GIS and its application in various urban cases are examined.

• The Transactions of the Korean Institute of Electrical Engineers
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• v.44 no.1
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• pp.21-24
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• 1995

The larger and the more complicated the system size and configuration grow, the more serious the system loss problem becomes. Exessive system loss causes severs system voltage depression, which even may result in system voltage collapse. This paper proposes an effective tool for minimizing the system power loss by optimal re-location of the static condenser based on the system loss sensitivity index .lambda.$_{Q}$. It is possible to determine the optimal location and amount of VAR investment for minimizing the system loss by priority of .lambda.$_{Q}$ index given for each bus. Several computational techniques for avoiding divergency of the load flow solution are proposed. The loss sensitivity index .lambda.$_{Q}$ uses information of normal power flow equations and their Jacobians. Two case studies proved the effectiveness of the algorithm proposed.posed.

• 한국방재학회:학술대회논문집
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• 2008.02a
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• pp.325-328
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• 2008

After insufficient road facilities are expanded, it is more important to maintain performance of road facilities the time according to passing. When the road facilities are maintained optimally through proper maintenance, the total amount of investment can be minimized and national competitiveness is improved. Individual maintenance research of road facilities such as PMS or BMS was in progress until currently, but it is difficult to joint ownership and share information between systems, and it is impossible to use as the decision-making. Therefore, Asset Management System for road facilities is enforced to solve the inefficiency of existing systems, maintenance the road facilities systematically under the limited budget and get the maximum benefits against the cost from the view point of long-term. In this paper, the concept of Asset Management System explained, and research plan from KICT in order to introduce the Asset Management System of road facilities from 2008 hereafter for 5 years accounted.