• Journal of Korean Society of Industrial and Systems Engineering
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• v.47 no.3
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• pp.31-38
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• 2024

This paper chronicles the evolution of load-sharing parameter estimation methodologies, with a particular focus on the significant contributions made by Kim and Kvam (2004) and Park (2012). Kim and Kvam's pioneering work underscored the inherent challenges in deriving closed-form solutions for load-share parameters, which necessitated the use of sophisticated numerical optimization techniques. Park's research, on the other hand, provided groundbreaking closed-form solutions and extended the theoretical framework to accommodate more general distributions of component lifetimes. This was achieved by incorporating EM-type methods for maximum likelihood estimation, which represented a significant advancement in the field. Unlike previous efforts, this paper zeroes in on the specific characteristics and advantages of closed-form solutions for load-share parameters within reliability systems. Much like the basic Economic Order Quantity (EOQ) model enhances the understanding of real-life inventory systems dynamics, our analysis aims to thoroughly explore the conditions under which these closed-form solutions are valid. We investigate their stability, robustness, and applicability to various types of systems. Through this comprehensive study, we aspire to provide a deep understanding of the practical implications and potential benefits of these solutions. Building on previous advancements, our research further examines the robustness of these solutions in diverse reliability contexts, aiming to shed light on their practical relevance and utility in real-world applications.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.34 no.1
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• pp.74-79
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• 2011

Engineering valuation is a specialized discipline requiring expert knowledge and judgment, which scientifically estimates the economic value of industrial properties. By industrial properties, we mean engineering structures such as mines, factories, buildings, machines, and other industrial facilities as well as facilities of public enterprises. Particular industrial properties can have longer economic life if their performance is excellent and they are still suitable for current manufacturing needs. If not, its economic life will be shorter. As speed of technological progress becomes rapid, life-cycle and development period of a product is becoming shorter. In an industry characterized by rapid development of technology, industrial properties can become obsolescent faster. Even if they are in good working order, they could be no longer suitable for manufacturing new products based on radically different technology. In our research, we apply engineering approach to estimating functional economic life by factoring in technological obsolescence in such an industry.

• Journal of Korean Society of Environmental Engineers
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• v.32 no.9
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• pp.818-829
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• 2010

This paper provides an extensive overview of the literature on economic analysis of climate change, and thereby provides direction for effective adaptation policies for Korea. The paper first gives a comprehensive look on the estimation of economic costs of climate change as given by various research. Following, the paper examines the choice of measures that are used in the economic analysis of climate change by different sectors, including agriculture and human health. The paper also compares and discusses the various analytic results with a focus on Korea in order to shed light on where Korea stands. Finally, the paper examines current literature on adaptation polices in response to climate change, and by examining how such research has evolved and deepened with time, provide directions for the research on adaptation policies for Korea.

• Journal of the Korean Home Economics Association
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• v.40 no.10
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• pp.161-176
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• 2002

This study is a basic research for the estimation of the value of unpaid household labor within the national economy system to be reflected in the related policy-making. By measuring economic value of unpaid household labor and estimating the ration to GDP, this study attempted to confirm the productivity of the unpaid household labor and thus contribute to the improvement of socio-economic status of women. Especially, it focused on the development of a standard of estimating unpaid household labor as a method applicable to the present economic and legal system. To organize the method of economic valuation of unpaid household labor and calculate the ration to GDP, this study used three approaches: replacement cost method individual function, replacement cost method generalist and opportunity cost method. Although the estimated result revealed that the economic value of unpaid household labor showed a great extent of deviation according to the estimating methods and the wage rate, total value of household labor ranged from one hundred and thirty eight to two hundred and thirty trillion wens, about 28-48% of GDP in Korea.

• Journal of the Korean Institute of Rural Architecture
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• v.7 no.3
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• pp.1-8
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• 2005

Decrease in Population and graying of rural area by industrialization and urbanization are gone continuously. This makes happened various rural problems and the differential of standard of living with is arising day by day. Government is unfolding rural supporting project to solve continuously these problems. Recent Projects which are choosing not top-down process by government leading but bottom-up process through village inhabitants' participation and expert consultant get positive estimation. But those have difficulties because the support is attained only in the beginning step not continuously and inhabitants' number by graying is decreasing. The Special Economic Zone for Regional Development Policy is new access that regulation can differ according to special quality of each area depending on Localization Age. Through this transfer the competence that can mitigate or reinforce various regulations according to special quality of area in local government. So, back and maintain activation systematically so that each area could be developed specially. The purpose of The Special Economic Zone for Regional Development Policy is the activation of regional economy through development that regional specific character is. And there is characteristic that local government plans and takes the lead in all project contents, government gives regulation benefit by appointing the special economic zone and do not support finance and various tax remissions. Through investigation of such new policy, I wish to recognize what long-term plan and method could be possible to success rural activation continuously.

• Environmental Engineering Research
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• v.24 no.1
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• pp.63-73
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• 2019

This study suggests a method for calculating the benefits of water pipe renewal based on an estimate of the water supply suspension risk. The proposed method based on five benefit items is more direct and specific than other benefit estimation methods. In addition, a methodology evaluating the economics of pipe renewal based on pipe failure rate is proposed for estimating the optimal renewal point from an economic perspective. By estimating the optimal renewal period based on a yearly benefit cost ratio per pipe in a case study area, it was possible to draft an optimal renewal plan for the subject region from an economic perspective. Compared with other methodologies, a reasonable optimal renewal period was derived from an economic point of view. The result of this study may be used to develop future water pipe renewal plans. Moreover, the proposed methodologies and results derived from this study can be applied to asset management plans.

• The Journal of Asian Finance, Economics and Business
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• v.10 no.1
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• pp.133-143
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• 2023

The detrimental impacts of financial instability on the world economy during the financial crisis highlighted the requirement to understand the existing financial circumstances. Stability and developments in financial conditions are important for economic prosperity. This study analyses the impact of geopolitical risk on the economic conditions of some specific emerging economies using monthly data from January 1999 to September 2016 by applying a fixed-effects panel data model. The estimation results demonstrated that geopolitical risk has a significant, negative impact on financial conditions. It shows geopolitical risk could be seen as a key factor that contributes towards financial conditions. Further, it implies that negative shocks of high geopolitical risk experienced by emerging economies are one of the primary reasons for the financial conditions' deterioration. The findings provide important insights for governments, policymakers, and investors. For instance, governments and politicians should refrain from expressing or producing tension, economic discomfort, or news that is likely to increase a high geopolitical risk. Maintaining a close eye on geopolitical risk and its sources may also help to stabilize financial conditions and develop a well-functioning financial system. As a result, investors would be better informed about an economy's economic and financial conditions, allowing them to diversify their international portfolios and devise investing strategies during uncertain economic times.

• International Journal of Reliability and Applications
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• v.2 no.3
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• pp.189-197
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• 2001

The estimation of mean lifetimes in presence of interval censoring with mixed replacement procedure is examined when the distributions of lifetimes are exponential. It is assumed that, due to physical restrictions and/or economic constraints, the number of failures is investigated only at several inspection times during the lifetime test; thus there is interval censoring. The maximum likelihood estimator is found in an implicit form. The Cramor-Rao lower bound, which is the asymptotic variance of the estimator, is derived. The estimation of mean lifetimes for competing failures model has been expanded.

• Journal of Applied Biological Chemistry
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• v.44 no.4
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• pp.194-198
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• 2001

Contaminated sites are often abandoned for an extended period of time, thus organopollutants becoming sequestered. The information on the initial concentrations of the contaminants would be helpful for the economic bioremediation of the chemicals. The present study estimated the initial concentrations of atrazine and phenanthrene through multiple regression analyses using soil properties and the amount of chemicals available in situ. Percentage mineralized or extracted was best correlated with organic C or logarithm of organic C, and the $R^2$ values were 0.548 and 0.894 for atrazine and phenanthrene, respectively. Estimation of the initial concentration of the chemicals was then calculated from both the percentage mineralized or extracted and the amount of chemicals extracted or mineralized. Results showed that the estimation of the initial concentration of the chemical at the time of contamination is feasible.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.57 no.3
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• pp.369-374
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• 2008

This paper presents the evaluation procedures and the estimation method for the estimation of optimal rebate level for EE(Energy Efficiency) programs. The penetration amount of each appliance is estimated by applying price function to preferred diffusion model resulted from model compatibility test. To estimate the optimal rebate level, two objective functions which express the maximum energy saving and operation benefit are introduced and by multi-objective function which can simultaneously consider two objective functions the optimal rebate level of each appliance is estimated. And then, using the decided rebate level and each penetration amount, the priority order for reasonable investment of each high-efficiency appliance is estimated compared to the results of conventional method. Finally, using a benefit/cost analysis based on California standard practice manual, the economic analysis is implemented for the four perspectives such as participant, ratepayer impact measure, program administrator cost and total resource cost.