• Journal of the Korea Safety Management & Science
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• v.7 no.4
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• pp.49-59
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• 2005

This paper is to propose various safety design models of tolerance specifications with different consumer requirements. In these models, tolerance specifications can be jointly determined by considering all the stochastic, economic, robust and engineering safety design factors with various characteristics of interest. In this paper, the proposed models are easily formulated for design engineers.

• Journal of Korean Institute of Industrial Engineers
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• v.22 no.3
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• pp.473-483
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• 1996

For situations where there are several markets with different price/cost structures, economic complete inspection plans are developed for determining the market to ship the product to. Two complete inspection plans are considered; the plan based on the performance variable of interest, and the plan based on a variable which is correlated with the performance variable. Profit models are constructed which involve selling price, cost incurred by imperfect quality, and quality inspection cost. Methods of finding the optimal complete inspection plans are presented and a numerical example is given.

• Proceedings of the PSK Conference
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• 2002.10a
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• pp.395.1-395.1
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• 2002

Many of the chiral NSAIDs are marketed as racemates. There is an increasing interest in developing the enantiomerically pure forms of the NSAIDs because the anti-inflammatory activity of NSAIDs have previously been shown to be largely sterospecific for the (S)-(＋)-enantiomer. Therefore, simple and economic preparative method to identify the (S)-(＋)-enantiomer of NSAIDs (aryl propionic acids) as diastereomeric solvation complex was developed using several chiral solvating agents by recrystallization of racemate and solvent fractionation. (omitted)

• Journal of Korea Port Economic Association
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• v.32 no.2
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• pp.59-71
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• 2016

This study empirically examines the dynamic specification of the ship price model based on a vector autoregressive model and data covering from January 2000 to October 2014. Our results are summarized as follows: first, the relationship between ship price and interest rate shows significantly negative and the relationship between ship price and freight rate shows positive. It provides consistent implication that ship price depends on interest rate and freight rate under the dynamic Gordon model. Second, we apply an impulse response analysis to ship price and find the responses of the ship price from both factors, interest rate and freight rate, which affect during seven periods approximately. Finally, the results of a variance decomposition indicate that freight rate is more important than interest rate on the ship price.

• Journal of Labour Economics
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• v.41 no.4
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• pp.107-131
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• 2018

This paper presents a model for the Minimum Wage Commission's decision process and analyzes the strategic actions of the participants in the process. The Minimum Wage Commission has used two ways of setting the minimum wage. The commission has voted either on the labor's against the management' final proposals or has voted on the public interest commissioners' proposal. According to the model, the minimum wage is determined at a level that is very close to or at a level preferred by the median voter among the public interest commissioners. But the probability of adopting labor or management proposal is ex-ante the same. Empirical evidence from the minimum wage decision process is consistent with the predictions of the model. The probability of adopting the labor's proposal in the minimum wage commission voting is not statistically significantly different from 50%. The model also suggests that the preference of the median voter among public interest commissioners determines the minimum wage level. Since the government appoints public interest commissioners and thus, in fact, the median voters, the government can decide the minimum wage level. This proposition is also consistent with data. The annual growth rate of the minimum wage under the progressive governments is higher than under conservative governments.

• Journal of Digital Convergence
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• v.17 no.10
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• pp.169-176
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• 2019

Recently, the Korean economy is congested with Japan's economic retaliation, the US-China trade war, the Bank of Korea's 0.25% base rate cut and Korea's economic growth forecast revision. The purpose of this study is to analyze the KOSPI, CPI, Treasury bonds(3 years) Interest rate & sales performance of all industries, and examine the impact of each index on the KOSPI. The analysis period is from January 2003 to June 2019, and the effect of each index on the KOSPI is analyzed. In numerical analysis, we performed correlation coefficients and regression analysis. In the model analysis, the distribution, quadrant, scatter, box-plot and impulse response were examined. This study examined the volatility and dynamic characteristics of each index. As a result, the KOSPI showed a high correlation with sales and Treasury bonds, but showed a very low correlation with the CPI. The KOSPI will continue to be affected by sales and interest rates.

• Journal of Electrical Engineering and Technology
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• v.10 no.3
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• pp.895-904
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• 2015

This paper presents a probabilistic approach of reliability evaluation and economic assessment for solving transmission network expansion planning problems. Three methods are proposed for TNEP, which are reorganizing the existing power system focused on the buses of interest, selecting candidates using modified system operating state method with healthy, marginal and at-risk states, and finally choosing the optimal alternative using cost-optimization method. TNEP candidates can be selected based on the state reliability such as sufficient and insufficient indices, as proposed in this paper. The process of economic assessment involves the costs of construction, maintenance and operation, congestion, and outage. The case studies are carried out with modified IEEE-24 bus system and Jeju island power system expansion plan in Korea, to verify the proposed methodology.

• Journal of the Korea Society for Simulation
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• v.13 no.2
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• pp.35-43
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• 2004

The purpose of this study is an economic analysis of power plant utilities by comparing electricity generating cost including environmental costs. Considering the enormous role of electricity in the national economy, it is very important to study the effect of environmental regulation on the electricity sector. Because power utilities need for large investment during construction, operation and maintenance, and also require much construction lead time. Economic analysis is the important process in the electric system expansion planning. This paper compares the costs of electricity generation including environmental costs between a coal-fired power plant and an LNG combined cycle power plants. With the simulation, this study surveys the sensitivity of fuel prices, interest rate and carbon tax. In each case, this sensitivity can help to decide which utility is economically better in environmental regulation circumstance.

• Journal of the military operations research society of Korea
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• v.23 no.1
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• pp.138-150
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• 1997

The life-cycle of the K-1 tank has been 10 years simply applying that of the U.S. M-1 tank. Therefore, this paper is focused on determination of an economic life-cycle for the K-1 tanks. The current operation cost is adjusted by interest rate and the depreciation cost is applied in this study for more reliable estimation of the life-cycle cost. The Equivalent Annual Method is utilized and then various regression techniques are applied for deriving an effective economic life-cycle. The economic life-cycle of the K-1 tank results in 13 years in this study. considering 95% confidence interval, the life cycle of the K-1 tank is between 10.5 years and 15.5 years.

• East Asian Economic Review
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• v.26 no.1
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• pp.27-48
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• 2022

In the past decade, Korea and Japan have increasingly exhibited different strategic priorities in trade in face of China's rising global economic prowess and worsening US-China trade conflict. Japan's trade policy decisions have worked to reinforce its economic and security ties with the US as a means to counter China. Japan has used both bilateral and multilateral means to secure its ties with the US against China. In contrast, Korea's trade policy positions have been one of 'strategic ambiguity'. Korea has been more conciliatory towards China, reluctant to take actions that would counter China's interest. Korea has mainly resorted to bilateral channels to maintain favorable relations with both China and the US. Korea's reluctance to clearly ally with the US against China has been observed across different administrations with opposing political orientations. This paper examines Korea and Japan's diverging strategic priorities in trade through the 2017 World Trade Organization Ministerial Conference; the 2017 US imposition of Section 232 on steel; the Comprehensive and Progressive Agreement for Trans-Pacific Partnership, the Korea-US FTA renegotiation and the Korea-China FTA Phase Two Negotiation; and the 2019 Japan-US Trade Agreement.