• Management Science and Financial Engineering
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• 제14권1호
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• pp.65-86
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• 2008

In this paper, we have considered the multicriteria quadratic plant location problem. In addition to the allocation costs, the maintenance costs of the plants are also considered. The objective functions considered in this paper are quadratic in nature. The given problem is reduced to the problem with linear objective function. The method of Fernandez and Puerto (2003) is applied to solve the reduced problem. It is illustrated with help of examples. The effect of the change in the allocation and maintenance costs on allocation of plants to the clients has also been discussed.

• 전기학회논문지
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• 제58권12호
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• pp.2354-2358
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• 2009

Demand response (DR) can be used to improve the efficiency of electricity markets and increase the reliability of power systems. As more utilities attempt to reduce the purchasing costs by implementing DR programs strategically, there is an increasing need for studies of how to allocate the reduced purchasing costs among DR program participants. The rebates or incentives can be given to DR program participants in proportion to the participants' contributions to the reduced purchasing costs. This paper presents Shapley Value-based method to determine the DR program participants' contributions to the reduced purchasing costs. A numerical example is presented to validate the effectiveness of the proposed method.

• 대한교통학회지
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• 제3권1호
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• pp.46-57
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• 1985

The objective of this paper is to derive a optimum distance and time taxi fare structure based on social costs. Social costs expressed in terms of congestion and vehicle operating costs were successfully internalized. Speed and volume data for three major arterials in Seoul CBD were used. Optimum congestion charge turned out to be 97.01 Won/Km which can be regarded as congestion tax in the context of Seoul CBD. This congestion tax can possibly be incorporated into time-based taxi fare structure. Congestion is likely to be reduced as a result of imposition of time-based taxi fare which reflects social costs.

• 한국경영과학회지
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• 제4권1호
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• pp.69-77
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• 1979

A single machine stochastic scheduling problem is considered. Associated with each job is its random processing time and random deferral cost. The criterion is to order the jobs so as to minimize the sum of the deferral costs. The expected sum of the deferral costs is theroretically derived under the stochastic situation for each of several scheduling decision rules which are well known for the deterministic environment. It is also shown that certain stochastic problems can be reduced to equivalent deterministic problems. Two examples are illustrated to show the expected total deferral costs.

• International Journal of Human Ecology
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• 제13권2호
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• pp.39-52
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• 2012

The purpose of this study is to compare the economic burden and cost of child rearing, mainly between families with job-holding mothers and job-exit mothers. The sample consisted of 665 mothers with at least one child aged one year or less from the 2009 Panel Study on Korean Children. We found social capital reduced the child rearing costs for both job-holding and job-exit mothers, while community resources significantly reduced the costs of child rearing only for job-holding mothers. Based on these results, implications for family policy for families with young children are suggested.

• 품질경영학회지
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• 제31권4호
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• pp.1-18
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• 2003

Quality is a critical competitive factor in today's environment because of the impact of quality on costs and delivery. Many companies regard quality as a key concept of company strategy in order to achieve the competitive edge. Measuring and reporting quality cost is the first step in quality management program. The supposition of quality cost model is that investment in prevention activities will bring rewards from reduced failure costs, and that further investment in prevention activities will show profits from reduced appraisal costs. In this study, the degree of quality cost deviation is conceptualized. This means a deviation between the ideal and present ranking in the amounts of quality cost categories. This study analysed that the effect of its deviation on quality management activity and performance variables. However, there are no difference in these variables. The major reason is that most of companies are endeavoring for quality management but operating quality cost system unsystematically. The review against a prevention and appraisal activity is necessary.

• International Journal of Railway
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• 제5권3호
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• pp.103-113
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• 2012

Infrastructure costs could be greatly reduced if the need for bridges and tunnels was reduced, or if the line could be shortened. Tilting trains might be a less costly alternative to building new tracks with large curve radii, because tilting trains can negotiate tighter curves without having to decrease their speeds. Tracks built for tilting trains would be cheaper, as they require fewer bridges and tunnels. This paper compares the construction costs of two different options for the new Dodam-Yeoncheong section on the Central line, which includes 148.65 km of new electrified double-track with a design speed of 250 km/h. The first option is to straighten the high-speed line. The second option is to build a line with small radii curves and run tilting trains on the line. In the first option, tunnels would account for about 51% of the new section. In comparison, the second option would have shorter curves and fewer tunnels and bridges which would reduce construction costs. Furthermore, alignment modifications could be made to several segments on the straight line, making the most of the existing roadbed. The analysis concluded that the line suited to tilting trains would be 95.7 million USD cheaper to build the straight route. That is a savings of 2.8% of the total project cost. However, this option would increase the total travel time of the route by 1.2 minutes, which means it is not necessarily the best choice.

• Journal of Information Processing Systems
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• 제2권2호
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• pp.67-75
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• 2006

In order to acquire a precise and quick response to an analytical query, proper selection of the views to materialize in the data warehouse is crucial. In traditional view selection algorithms, all relations are considered for selection as materialized views. However, materializing all relations rather than a part results in much worse performance in terms of time and space costs. Therefore, we present an improved algorithm for selection of views to materialize using the clustering method to overcome the problem resulting from conventional view selection algorithms. In the presented algorithm, ASVMRT (Algorithm for Selection of Views to Materialize using Reduced Table), we first generate reduced tables in the data warehouse using clustering based on attribute-values density, and then we consider the combination of reduced tables as materialized views instead of a combination of the original base relations. For the justification of the proposed algorithm, we reveal the experimental results in which both time and space costs are approximately 1.8 times better than conventional algorithms.

• 한국식품과학회지
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• 제28권4호
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• pp.673-677
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• 1996

지방과 재고미의 함량 변화에 따른 분쇄 우육의 pH 차이는 거의 없었으며 재고미의 첨가량이 5에서 20%로 증가할수록 가열후 수율도 증가하였다. 10% 지방 우육과 30% 지방 우육의 콜레스테롤 함량은 비슷한 수준이었으며 10% 지방육의 경우 재고미의 첨가량이 증가할수록 제품의 콜레스테롤 함량은 감소하였다. 분쇄 우육의 지방 함량을 30%에서 10%로 줄였을 때 열량은 50% 정도 감소하였고 육 100 g당 생산원가는 재고미를 5, 10, 20% 첨가하였을 때 각각 4.9, 9.9, 19.8%의 비율로 절감되었다. 결론적으로 분쇄 우육의 지방 함량을 30에서 10%로 줄이고 대신 재고미를 첨가하면 가열 수율은 높아지고 열량과 생산 원가는 절감되며 10% 지방육의 경우 재고미의 함량이 증가할수록 콜레스테롤 함량은 감소하는 유익한 효과가 확인되었다.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1993년도 한국자동제어학술회의논문집(국제학술편); Seoul National University, Seoul; 20-22 Oct. 1993
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• pp.524-529
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• 1993

Component Cost Analysis considers any given system driven by a white noise process as an interconnection of different components, and assigns a metric called "component cost" to each component. These component costs measure the contribution of each component to a predefined quadratic cost function. One possible use of component costs is for model reduction by deleting those components that have the smallest component cost. The theory of Component Cost Analysis is extended to include finite-bandwidth colored noises. The results also apply when actuators have dynamics of their own. When the dynamics of this input are added to the plant, which is to be reduced by CCA, the algorithm for model reduction process will be called Weighted Component Cost Analysis (WCCA). Closed-form analytical expressions of component costs for continuous time case, are also derived for a mechanical system described by its modal data. This is very useful to compute the modal costs of very high order systems beyond Lyapunov solvable dimension. A numerical example for NASA's MINIMAST system is presented.presented.