• Journal of Korea Society of Industrial Information Systems
• /
• v.23 no.5
• /
• pp.145-157
• /
• 2018

The purpose of this study is to explore ways of service recovery and procedures through the service failure cases depending on the employee capacity that leads to improving quality of the airline cabin service. This study was tested using the failure case of airline in korea. Since interrupting and discontinuing of customer service affect customer defections, customer satisfaction must quickly respond to the service's error situation. The service of the cabin crew is closely related to the customer's evaluation, the direct connection. Customer's objectives are to meet employee needs for service recovery and to recognize and analyze customer perceptions of human resources services, restore customer expectations and maintain contracts with customers. Therefore, this study proposes a set of strategies for effectively preventing and responding to customer related service failure in the airline cabin service.

• Journal of Korea Water Resources Association
• /
• v.31 no.4
• /
• pp.407-413
• /
• 1998

This study reviewed the recent studies for the climate change impact on water resource systems and applied one of the techniques to a real reservoir system - the Skagit hydropower system in U.S.A. The technique assumed that the climate change results in ±5% change in monthly average and/or standard deviation of the observed inflows for the Skagit system. For each case of the altered average and standard deviation, an optimal operating policy was derived using s SDP(Stochastic Dynamic Programming) model and compared with the operating policy for the non-climate change case. The results showed that the oparating policy of the Skagit system is more sensitive to the change in the streamflow average than that in the streamflow standard deviation. The derived operating policies were also simulated using the synthetic streamflow scenarios and their average annual gains were compared as a performance index. To choose the best operating policy among the derived policies, a Bayesian decision strategy was also presented with an example. Keywords : climate change, reservoir operating policy, stochastic dynamic programming, Bayesian decision theory.

• Journal of the Korean Data and Information Science Society
• /
• v.27 no.4
• /
• pp.959-967
• /
• 2016

Distributional assumptions on equity returns play a key role in valuation theories for derivative securities. Elberlein and Keller (1995) investigated the distributional form of compound returns and found that some of standard assumptions can not be justified. Instead, Generalized Hyperbolic (GH) distribution fit the empirical returns with high accuracy. Hu and Kercheval (2007) also show that the normal distribution leads to VaR (Value at Risk) estimate that significantly underestimate the realized empirical values, while the GH distributions do not. We consider saddlepoint approximations to estimate the VaR and the ES (Expected Shortfall) which frequently encountered in finance and insurance as measures of risk management. We supposed GH distributions instead of normal ones, as underlying distribution of linear portfolios. Simulation results show the saddlepoint approximations are very accurate than normal ones.

• Proceedings of the Korea Contents Association Conference
• /
• 2008.05a
• /
• pp.324-327
• /
• 2008

This research seeks to investigate the economic feasibility of a small size aircraft development and BASA certification enterprise. To achieve the objective, this research investigates cost which requires for proceeding a small size aircraft development and BASA certification enterprise. This research also investigates the economic effects and economic benefits acquired from exporting civil aircraft. Costs and benefits are assumed using cash flow by types of airplanes. On the basis of the cash flow, this research calculates B/C ratio, NPV, IRR for investigating the economic feasibility. The result shows that there are economic feasibility for both very light jet and piston aircraft. Between these two aircraft types, more economic feasibility exist for very light jet than piston aircraft.

• Journal of Korea Port Economic Association
• /
• v.31 no.2
• /
• pp.1-21
• /
• 2015

This study verifies the change in market conditions in the Korea-China and Korea-Japan car ferry routes. Variation in historical development has led to differences in the lifecycle stages of these two car ferry shipping markets. However, previous studies have focused on individual car ferry routes rather than offering a more general understanding of this market. Based on the foregoing, we investigate the international car ferry market conditions from/to Korean ports, assess the management performances of car ferry companies, analyze the lifecycle stages of each car ferry route, and offer insights into the future of these markets. We show that the competitive market conditions and demands of passengers and cargoes differ between these routes. As for the market stage, we conclude that the Korea-China route is entering a mature market, whereas the Korea-Japan route is entering a declining stage.

• Journal of Korean Society of Forest Science
• /
• v.110 no.3
• /
• pp.453-461
• /
• 2021

The energy use of forest biomass is crucial to deal with climate change and achieve the carbon-neutral goal. This study aims to analyze the economic feasibility of forest biomass thermal energy facilities and calculate the optimal subsidy level of heat supply to ensure continued operation of the facilities. To achieve this aim, the net present value approach (NPV) and call option price model are adopted considering wood chip price volatilities. The Forest Energy Self-Sufficient Village Project financed by Korea Forest Service is considered as the research case study. In our analysis, when 50% of the initial investment is given to the subsidies and RECs are applied to only power generation, NPV and IRR are both negative and the investment value using the real option model is also zero. We concluded that some heat subsidies should be acknowledged to keep the facilities operating. Besides, the simulation results reveal reliable economic values when the heating subsidy is priced at KRW 0.0248 per kcal.

• Journal of Korean Society of Industrial and Systems Engineering
• /
• v.42 no.1
• /
• pp.137-142
• /
• 2019

There are two methods for evaluating two or more mutually exclusive projects. One is a total investment approach and the other is an incremental investment approach. The former can rank projects by the criterion of the net present value, but the latter can't do it. An incremental investment approach is only possible when all pairwise alternatives are compared. Thus an incremental investment approach is superior in ranking them over an incremental investment approach. To do so, a principle of comparison must be established. Comparisons of profitability are reasonable when operating the same amount of investment over the same period of time. One principle is that all projects are invested in the largest of the projects. Another principle is that all projects are invested during the longest project life of the projects. In this paper, even if the principle is followed, it will be shown that the external rate of return fails to rank them. However, the productive rate of return criterion would prove to be able to rank them like the net present value standard, provided that the principle of comparison is kept. In addition, rate of returns can be assessed so that all mutually exclusive projects can be compared at once, such as on the criterion of the net present value. That is, it can be also compared with many other returns, such as the profit rates on financial investments or real investments.

• Journal of Teachers' Pension
• /
• v.4
• /
• pp.91-123
• /
• 2019

본 연구는 2009년 법 개정에 따른 기준소득의 변경이 가입자별 보험료 부담과 연금급여의 변경에 어떠한 영향을 주었는지를 구체적 사례를 중심으로 살펴봄으로써 제도 변경 전후의 가입자별의 연금소득 변화를 산정함과 아울러, 2015년 사학연금법 개정에 따른 사학연금 가입자간 소득재분배제도의 도입이 2009년 법 개정에 따른 연금소득효과에 어떠한 영향을 주었는지를 분석하였다. 분석 결과, 사학연금가입자의 경우 법 개정 당시의 전제가 되었던 기준소득대비 보수월액의 비율인 65% 수준에 근접하는 사람은 일부에 불과한 것으로 나타났다. 즉, 60~70%기준에 포함되는 계층은 5.6%에 불과하고, 60% 이하인 자가 88.6%, 70% 이상인 자는 5.8%로 나타났다. 이는 사학연금 가입자 상당수가 기존의 보수월액이 실제 과세소득의 일정비율보다 낮은 위상에 있었음을 의미한다. 따라서 2009년 법 개정 결과, 처음의 기대와는 달리 개정 이전 연금액에 비하여 높아지는 가입자가 87.5%, 낮아지는 가입자가 12.5%인 것으로 나타났다. 그렇지만 연금액이 증가되었지만 보험료 부담이 함께 증가되었기 때문에 수익비 측면에서 더 유리해졌다고 할 수 없다. 더 부담하고 더 많이 받는 경우가 대다수였다. 물론, 오히려 기준소득이 보수월액보다 절대치조차 낮은 가입자도 있었다. 이 경우, 본인의 희망에 따라 법령에서 별도로 정한 최저소득기준을 선택할 수 있도록 함으로써 문제점이 완화되었다. 2009년 법 개정 상에 나타난 연금액 증가는 소득재분배 요소를 도입한 2015년 법 개정으로 상대적으로 저소득 가입자는 연금액이 증가하고 고소득자는 연금액이 감소됨으로써, 2009년 법 개정에서 나타난 고소득자에게 유리할 수 있는 부분이 완화되는 결과를 만들었다. 2015년 개정은 2009년 개정 상 발생한 문제를 다소 보완하는 결과가 되었다. 공무원의 보수월액을 적용하여왔던 제도를 기준소득월액으로 바꾼 것은 사학연금 가입자가 실제의 소득에 기초하여 보험료를 부담하고 연금을 지급받을 수 있도록 되었다는 점에서 제도의 정상화로 보는 것이 바람직하다. 소득기준의 전환으로 내재적으로 혼란이 발생할 가능성이 있었지만, 2015년의 법 개정으로 제도가 보다 완결적으로 발전가능하게 된 것으로 평가된다.

• Journal of Convergence for Information Technology
• /
• v.11 no.1
• /
• pp.28-33
• /
• 2021

Since the stock price is a measure of the future value of the company, when analyzing the stock price, the company's growth potential, such as sales and profits, is considered and invested in stocks. In order to set the criteria for selecting stocks, institutional investors look at current industry trends and macroeconomic indicators, first select relevant fields that can grow, then select related companies, analyze them, set a target price, then buy, and sell when the target price is reached. Stock trading is carried out in the same way. However, general individual investors do not have any knowledge of investment, and invest in items recommended by experts or acquaintances without analysis of financial statements or growth potential of the company, which is lower in terms of return than institutional investors and foreign investors. Therefore, in this study, we propose a research method to select undervalued stocks by analyzing ROE, an indicator that considers the growth potential of a company, such as sales and profits, and predict the stock price flow of the selected stock through deep learning algorithms. This study is conducted to help with investment.

• The Journal of the Korea Contents Association
• /
• v.22 no.6
• /
• pp.692-700
• /
• 2022

This study was conducted to analyze firms' death rate and impact factors on the death of Foreign-invested Companies in Korea which is between 20013 and 2017. Cox Proportional Hazard Model took to conduct on the death impact factors, such as 2 characteristics factors of the firm, and 4 financial characteristics variables, variables, and 4 profitability factors. As a result of the impact factors of Foreign-invested Companies' death the Labour(NE) variables of characteristics firm had negative effects. And the Debt(LB), Operating Profit (OP), and Sales Profit (SP) of the financial characteristics had a negative effect. Other factors did not produce significant results. As a result of an empirically comparative analysis of the mortality rate of foreign-invested companies by the Kaplan-Meier method, it was analyzed that fully owned companies and large enterprises had lower extinction risk and greater sustainable management potential than joint ventures or SMEs.