• Proceedings of the Korea Water Resources Association Conference
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• 2002.05b
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• pp.829-836
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• 2002

The paper presents a multi-objective genetic algorithm approach to the design of a water distribution network. The objectives considered are minimization of network cost and maximization of a reliability measure. In this study, a new reliability measure, called network resilience, is introduced. This measure mimics a designer's desire of providing excess power at nodes and designing reliable loops with practicable pipe diameters. The proposed method produces a set of Pareto-optimal solutions in the search space of cost and network resilience. Genetic algorithms are observed to be poor in handling constraints. To handle constraints in a better way, a constraint handling technique that does not require a penalty coefficient and applicable to water distribution systems is presented. The present model is applied to two example problems, which were widely reported. Pipe failure analysis carried out on some of the solutions obtained revealed that the network resilience based approach gave better results in terms of network reliability.

• Journal of the Korean Data and Information Science Society
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• v.18 no.3
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• pp.689-696
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• 2007

This paper considers a Bayesian approach to determine an optimal PM policy with random maintenance quality. Thus, we assume that the quality of a PM action is a random variable following a probability distribution. When the failure time is Weibull distribution with uncertain parameters, a Bayesian approach is established to formally express and update the uncertain parameters for determining an optimal PM policy. Finally, the numerical examples are presented for illustrative purpose.

• Proceedings of the Safety Management and Science Conference
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• 2008.04a
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• pp.47-51
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• 2008

Recently, the development of technology has been rapidly proceeding with information technology in various fields. Due to their abstract properties, proper evaluation of intangible assets is very difficult compared to evaluation of tangible assets. Intangible assets are knowledge, technology, and design etc. In general there are two approaches to evaluate the intangible assets such as qualitative and quantitative approach. The qualitative approach contains scoring approach, profile approach, checklist approach, and quantitative approach. Quantitative approach contains cost approach, market approach, income approach, and real-option approach. As an initial step for evaluation of safe work environments, this study compares and analyzes evaluation methods of intangible assets.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.26 no.3
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• pp.115-121
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• 2014

HVAC&R system costs can often be one of the most expensive components, representing approximately 15% of the total construction cost for office buildings. Despite their significant importance, there is a lack of a consistent and homogeneous framework to approximate the estimate research. This research deals with the prediction methodology of HVAC&R system cost with the aim of establishing a common idea for the analysis of the construction cost estimate. Our approach deals with the concept of an HVAC&R set that is composed of subsystems. The matrix combination analysis is examined, and total 960 HVAC&R system cost estimation can be implemented to large scale office buildings.

• Korean Management Science Review
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• v.8 no.1
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• pp.41-50
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• 1991

Within the current construction industry, constractor equipment management practices lack structure and often are not addressed through an economic analysis and evaluation process. This paper explores two areas...cost of capital and inflation...with the intention of providing insight for a more structured and economic based approach to contractor equipment replacement practices rather than by the traditional "rule of thumb".umb".uot;.

• The Journal of the Korean dental association
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• v.52 no.7
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• pp.416-424
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• 2014

The purpose of this study is to analyze the cost of dental implant by top-down method and, on that basis, to provide salient information for the suitable standard of dental insurance fee. A survey data and accounting documents from 36 samples of dental clinics secured with the organisation authority are used and analysed for extracting the representative sample of dental clinic. A researcher visited the dental clinics in person and conducted additional interviews in the omitted case of accounting documents. A dental implant cost by top-down method was estimated to 1,430,000 won. Labor cost accounted for 43% of the total cost structure, ranking it 1st and, management cost, material cost and interest cost on investment cost in order are investigated. Labor cost counts of the total cost that shows the similar aspect to the existing result. Cost in cost accounting of medical care would be used for the judge that cost pursed value for dental service, not price or fee.

• Journal of Korean Institute of Industrial Engineers
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• v.15 no.2
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• pp.77-86
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• 1989

A fully automated cost estimation system(FACES) has been developed. Since speed, accuracy, and consistency are essential factors in automating a cost estimation, the use of computers in cost estimation system(CES) has grown rapidly in the last few years. FACES is a micro computer based cost estimation system that employs a manufacturing knowledge base. A Group Technology(GT) based part classification and coding(C&C) scheme is used to automate the process planning aspects of cost estimation. Variant process planning methods are employed to generate workstation routings from form features of the part. The system has been tested for an assembly of six machined parts. Results indicate that the system could provide a substantial improvement in accuracy, productivity, and performance over the more traditional full dialog approach to cost estimation. It also provides a good foundation for a factory automation by using a common GT based database through design to production.

• Journal of Aerospace System Engineering
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• v.9 no.2
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• pp.41-46
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• 2015

The various risk factors that affected schedule, costs and mission success, etc. in development of the satellite. This paper derives the considerable "Cost of Quality" factors in the satellite development phase through the survey of practical techniques in respect of measurement of quality cost in the commercial products manufacturing, and proposes mitigation strategy of quality cost using the approach that can be minimized it.

• Journal of Korean Society for Quality Management
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• v.16 no.1
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• pp.59-66
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• 1988

On-line QC by Taguchi has two approaches of: the cost-oriented (cost-emphasis) QC and the process-oriented (quality-emphasis) QC. The main concern of this paper is to estabilish and recommend a desirable one as a QC target. Simulation is employed to solve the question, and the failure cost (A), appraisal cost (B), and prevention cost (C) are adopted as decision variables. In conclusion, the process-oriented QC is the recommendable approach as far as there is no remarkable cost difference between the two approaches and possible to apply on.

• Journal of Korean Society for Quality Management
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• v.22 no.4
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• pp.132-151
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• 1994

Quality is a critical competitive factor in today's environment because of the impact of quality on market share, productivity and costs. Especially in Korean companies, the importance of quality is heightened as they are losing price competitiveness compared to the new industrialized countries. The traditional approach to quality improvement has been focused on workers. The primary means to achieving acceptable outgoing quality has been to inspect quality by adding more inspectors and inspection stations. This is an example of quality cost that can be reduced through the preventive actions against bad quality. Quality cost is best viewed as a measure of costs specifically associated with the achievement or nonachievement of product/service quality required by customers. This paper examines the concept of quality cost, provides guidance to implementing a quality cost system, and identifies the limitations of quality cost information. These limitations are the target for future research for an efficient and effective implementation of quality cost system.