• Environmental and Resource Economics Review
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• v.12 no.1
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• pp.121-135
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• 2003

The main purpose of this paper is to estimate environmental preference of advanced countries for water and air pollution. In doing so, we introduce home production. That is, we assume that pollution has not only negative effect on utility but also positive effect on production. Thus if the former is greater that the latter effect, the total effect of pollution is negative. In this paper, we investigated this effect of advanced countries by using GMM estimator. The main finding is that in case of air pollution. This effect is negative. This implies that in case of air pollution, the disutility effect is greater that productivity effect.

• Korean Management Science Review
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• v.25 no.2
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• pp.25-42
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• 2008

CDMA/TOD with asymmetric capacity allocation between uplink and downlink is a highly attractive solution to support the next generation mobile systems. This is because flexible asymmetric allocation of capacity to uplink and downlink usually improves the utilization of the limited bandwidth. In this paper, we mathematically formulate an optimal timeslot and code allocation problem, which is to maximize the total utility considering the numbers of codes(channels) allocated to each data class and the forced terminations of previously allocated codes. We also suggest a real-time integrated timeslot and code allocation scheme using Lagrangean relaxation and subgradient optimization techniques. Experimental results show that the proposed scheme provides high-quality solutions in a fast time.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 1998.10a
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• pp.162-165
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• 1998

We consider a facility layout problem for optimized material flow system design in the automated production system design. Existing facility layout algorithm have a weak point that arranged facilities have irregular shape or don't preserve their own shape and size. The proposed algorithm give a layout which is minimize total material handling cost and maximize space utility under preserving each facilities' own shape and size.

• Proceedings of the KIEE Conference
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• 2006.07a
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• pp.147-148
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• 2006

Recently, due to increasing the application of power electronic equipment, harmonics generated from the non-liner load are fairly produced. Harmonics can cause a variety of problems such as the overheating of distribution transformer, the breakdown of device and communication interference. Interest about power quality decline of power system is very increased. In this paper, we are measured the harmonic voltage and current o( power system to analyze harmonic characteristics, and it is analyzed Total Harmonic Distortion(THD). Also, we Ere modeled power system using PSCAD/EMTDC. And it is analyzed harmonic voltage and current in steady-state. The study results have been indicated the utility about harmonics analysis and modelling for power system.

• Proceedings of the KIEE Conference
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• 2005.07a
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• pp.748-750
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• 2005

This paper approaches a methodology for deciding the optimal reliability criteria for an optimal composite power system expansion planning considering generation and transmission systems simultaneously. A probabilisticreliability criterion, $LOLE_R$(Loss of Load Expectation), is used in this study. The optimalreliability criterion $LOLE_R*$ is decided at minimum cost point of total cost curve which is the sum of the utility cost associated with construction cost and the customer outage cost associated with supply interruptions for load considering forced outage rates of elements(generators and lines) in long term forecasting. The characteristicsand effectiveness of this methodology are illustrated by the case study using MRBTS size system.

• Journal of Power Electronics
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• v.10 no.3
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• pp.219-227
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• 2010

Telecom supplies need to conform to low Total Harmonic Distortion (THD) and high Power Factor (PF) as per IEC 61000-3-2 and IEEE 519-1992 standards. These high rating power supplies use a three phase utility in which low THD and high PF are realized via various passive and active wave shaping schemes. In this paper, a new design for three phase telecom power supplies is presented with circuit parameter values optimized for high performance in terms of a low THD, high PF, low ripple and high line and load regulation using a suitable combination of various strategies. The performance of the power supply is validated by extensive simulations.

• 한국정보디스플레이학회:학술대회논문집
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• 2003.07a
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• pp.626-629
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• 2003

In order to achieve high-resolution and large-size displays, inspection technology is necessary and important. It is a powerful utility for process and yield improvement for the high valued panel realization. We indicated the challenge of advanced panel manufacturing on inspection ability and throughput. We also investigated the method to judge laser-crystallizing energy by inspection technology. Finally, the total defect number and critical killer defects were classified and discussed in this work.

• Proceedings of the KIEE Conference
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• 1999.07b
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• pp.740-742
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• 1999

The demand for the high quality of utility electrical power has been increasing rapidly in recent years because of today's electrical energy dependent industries and most people's everyday lives based on computer systems. However, electrical power supply conditions to meet this high quality demand becomes more difficult and more due to a large portion of nuclear power plants output in total electrical power supply which normally do not respond to frequency variations, and high peak of air conditioner demands during the summer season. So the rest of power plants should be operated to show the best governor regulation performance to maintain the electrical power frequency quality.

• Journal of Korean Society for Quality Management
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• v.23 no.3
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• pp.126-139
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• 1995

We describe a formal approach to the construction of optimal classification rule for the two-group normal classification with equal population mean problem. Based on the utility function of Bernardo, we suggest a balanced design for the classification and construct the optimal rule under the balanced design condition. The rule is characterized by a constrained minimization of total risk of misclassification, the constraint of which is constructed by the process of equation between expected utilities of the two group conditional densities. The efficacy of the suggested rule is examined through numerical studies. This indicates that, in case little is known about the relative population sizes, dramatic gains in accuracy of classification result can be achieved.

• Proceedings of the Korean Institute of Interior Design Conference
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• 1999.04a
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• pp.53-56
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• 1999

The purpose of this study was to diagnose the characteristics of current use of kitchen and scrutinize what to improve for the future kitchen development. To achieve the purpose, the small group wordshop panel was used. Two groups of 5 housewives per each were employed. For each group, there were a total of 3 consecutive meetings including 2 workshops and 1 field survey in each subject's house. The contents dealt with in the panel were as follows. First, actual condition and problems of using kitchen; second , possible solutions of the problems; third, needs for developing future kitchen. The major results were first, consumers require bigger kitchens to accomodate a variety of family activities ; second, kitchen needed to be more open encouraging family interaction and gave organic relationship to adjacent such as living room and utility room; third, due to korean cooking style, poor ventilation along with wet trash disposal was a serious problem. In addition to these. there revealed many problems which need to be improved and valuable ideas for the improvement.