• 한국경영과학회지
• /
• 제14권2호
• /
• pp.53-66
• /
• 1989

The Public Vehicle Routing Problem (PVRP) is to find the minimum total cost routes of M or less Public-Vehicles to traverse the required arcs(streets) at least once, and return to their starting depot on a directed network. In this paper, first, a mathematical model is formulated as minimal cost flow model with illegal subtour elimination constraints, and with the fixed cost and routing cost as an objective function. Second, an efficient branch and bound algorithm is developed to obtain an exact solution. A subproblem in this method is a minimal cost flow problem relaxing illegal subtour elimination constraints. The branching strategy is a variable dichotomy method according to the entering nonrequired arcs which are candidates to eneter into an illegal subtour. To accelerate the fathoming process, a tighter lower bound of a candidate subproblem is calculated by using a minimum reduced coast of the entering nonrequired arcs. Computational results based on randomly generated networks report that the developed algorithm is efficient.

• KIEAE Journal
• /
• 제12권6호
• /
• pp.63-68
• /
• 2012

The aim of this study is to evaluate current policies and suggest the way of overcome financial impediments to the energy efficiency function of residential buildings. Based on this analysis the paper enumerates policy recommendations for enhancing how energy efficiency is addressed in building codes and other policies for residential buildings. For achieving this goal, this study conducts the cost-benefit analysis to measure total energy savings and associated total cost. The results of study shows that the cost is greater than the benefit from 1st to 4th year but the benefit will be greater than the cost for the rest of the year. In addition, this study designs a financial support method and an implementation mechanism. Investment from the capital market will take place with the government's interest subsidy. Home retrofit will be undertaken with low interest rate with 2.5% and the return will be paid by a monthly energy bill. The results of this study provides some useful insights for the policy design, including the importance of developing information tools for providing appropriate information to households.

• 한국컴퓨터정보학회논문지
• /
• 제16권5호
• /
• pp.51-60
• /
• 2011

이 연구에서는 기업 전자교육프로그램(e-learning program)의 효과성 평가를 위한 일종의 투자수익률 분석방법을 제안한다. 일반적으로 전자교육프로그램의 투자수익률 분석을 위한 정확한 비용과 수익 산출은 복잡한 과정이기 때문에 이를 분석하는 것은 용이한 일이 아니다. 이 때문에 지금까지 기업 전자교육프로그램의 투자수익률 분석에 대한 연구는 쉽게 찾아볼 수가 없다. 그러나 투자 대비 수익을 중시하는 기업 환경에서 교육투자수익률 분석은 교육훈련프로그램의 효과성을 검증하고 투자여부를 결정하는데 있어 매우 중요한 근거가 된다. 따라서 이 연구는 특정 회사의 전자교육프로그램의 투자수익률 분석을 시도함으로써 기업 전자교육프로그램의 투자대비 수익률을 규명하고자 하는 데에 구체적인 방안을 제공하고 다양한 기업 교육훈련프로그램의 투자수익률 분석을 위해 시사점을 제시하는 데 목적이 있다.

• Journal of Advanced Marine Engineering and Technology
• /
• 제38권9호
• /
• pp.1057-1063
• /
• 2014

국제사회가 관심을 가지고 있는 이산화탄소 배출 감소를 위해 많은 연구 기관들이 연료 절감 방법을 연구하여 결과를 제시하고 있다. 비용 절감이 최종 결론이지만 아직까진, 어떻게 제시된 방법이 작동되는가, 어떠한 효과가 있는가, 어떠한 크기의 배에 가장 이상적이며 효과가 클까 등등 많은 의문점들이 제기되고 있다. 선주와 운영자들에게는 연료비가 가장 큰 비용 중 하나이다. 그리고 연료 절감은 선주나 운영자들에게는 비용 절감과 동시에 이산화탄소를 줄이는 가장 좋은 방법이다. 본 논문은 추진 효율을 높여 연료를 절감하는 방법 및 투자되는 비용과 일 년 동안 운항 후 얻어지는 연료비 절감을 통하여 투자금 회수 기간을 대략적으로 계산을 할 수 있도록 하고, 각 방법 간의 미치는 영향에 대하여 소개를 하고자 한다.

• 한국유기농업학회지
• /
• 제19권spc호
• /
• pp.92-95
• /
• 2011

The initial investment of rice cultivation by mechanical technique was high. This was only due to the cost of planting machine. We analysed the overall cost (without machine cost) and benefits of the two methods, it manifested that the mechanical method is very much beneficial over traditional rice cultivation technique. We observed that the requirement of soil, irrigation water, number of seeds etc. decreased in mechanical cultivation technique while net income increase by 13.07% with 80% government subsidy. Furthermore, the initial rooting was quicker, growth and development of pot raised seedlings was better than the traditional technique. Hence, this technique can give better return to the farmers with the help of government subsidy.

• Asian Journal of Business Environment
• /
• 제12권1호
• /
• pp.1-9
• /
• 2022

Purpose: This study measures the effect of Information Technology (IT) on both cost and profit efficiency of State-owned Commercial Banks (SOCBs) in Bangladesh. Research design, data and methodology: Yearly Non-IT and IT data are collected from the annual report of SOCBs of Bangladesh from 2008 to 2017. Variable Return to Scale (VRS) cost Data Envelopment Analysis (DEA) and Profit DEA are employed to measure the efficiency of SOCBs and Ordinary Least Square (OLS) is used to investigate the impacts of ICT components on operating cost and profit efficiency for SOCBs. Results: The average cost efficiency (74.4%) was noticed higher than the average profit efficiency (20.6%) for SOCBs. SOCBs were more affordable and less profitable for both cost and profit efficiency. Rupali bank was the most cost efficient while Sonali bank was the most profit efficient. IT Investment and IT personnel expenses were positively significant for cost efficiency. IT income, IT personnel, IT personnel expenses, ATM expenses, and Credit card expenses were negatively significant for profit efficiency. Conclusion: The further studies can combine DEA with machine learning algorithms to study the impact of IT on banks' performances. The results could aid government to remove the hindrance of progress in Bangladesh.

• 수산경영론집
• /
• 제44권3호
• /
• pp.103-109
• /
• 2013

This paper analyzed that the economic effectiveness of the artificial fish reef project in the Tae-an Marine Ranching. Benefit-cost(B/C) model used to indicate the effects of economic valuation. B/C model is based on the sub-models which are Benefit Cost Ratio(BCR), Net Present Value(NPV) and Internal Ration of Return(IRR). First, the Sum of Incremental Benefit and Cost for total vessel by year in Artificial Fish Reef Area(AFRA) estimated 2,381 million won. And then, using 5.5% discounting rates and the survey data, the sub-models showed economically feasible in the all of analysis and analyzed the results as follows. BCR is 2.66, NPV is 28,014million won, and IRR is 22.78%. In conclusion, these results indicated that the artificial fish reef project in Tae-an Marine Ranching would be increase the income of fishermen as well as fish biomass.

• Management Science and Financial Engineering
• /
• 제10권1호
• /
• pp.25-41
• /
• 2004

There have been many studies to build a model that can help investors construct optimal portfolio. Most of the previous models, however, are based upon the path-breaking Markowitz model (1959) which is a quantitative model. One of the most important problems with that kind of quantitative model is that, in reality, most of the investors use not only quantitative, but also qualitative information when they select their optimal portfolio. Since collecting both types of information from the markets are time consuming and expensive, making a set of target assets smaller, without suffering heavy loss in the rate of return, would attract investors. To extract only desired assets among all available assets, we need knowledge that identifies investors' preference for the risk of the assets. This study suggests two-layer decision-making rules capable of identifying an investor's risk preference and an architecture applying them to a quantitative portfolio model based on risk and expected return. Our knowledge-based portfolio system is to build an investor's preference-oriented portfolio. The empirical tests using the data from Korean capital markets show the results that our model contributes significantly to the construction of a better portfolio in the perspective of an investor's benefit/cost ratio than that produced by the existing portfolio models.

• 대한설비공학회지:설비저널
• /
• 제10권4호
• /
• pp.304-315
• /
• 1981

This paper presents, the result of the study for the fluctuant temperature of the out-side air adopting the heat pump system in seoul, Taejean, Taegu, Busan and Jejeu among principle cities in korea for the purpose of checking the heating capacity, Heat pump capacity (outlet capacity), Coefficient of performance and running cost in comparison with the supporting the energy for the boiler's operation. According to the supply temperature changes of the out door coil by the out side air-return air mixing ratio, the Coefficient of performance is increased from 3. 1 to 5.0. Particularly, in Taegu, it is necessary to adopt the heat pump system against the supplement heat supply on the full outside air intake in January of the heating period, and it was recognized that the running cost is cheaper than that of the Boiler use. At the same time, if it is able to get $25\%$ of return air of the inside in the Seoul, it could be saved its costs when we use the supplementary boiler. And I think it is necessary to the development.

• The Journal of Asian Finance, Economics and Business
• /
• 제7권9호
• /
• pp.283-291
• /
• 2020

Although the corporate governance plays a crucial role in protecting shareholder wealth, the effect of corporate governance on cost of debt is unclear. On one hand, the corporate governance reduces asymmetric information between corporate and external investor including debtholder leading to a decreasing in cost of debt financing. On the other hand, bondholders require higher rate of return for an improvement corporate governance. Hence, this study aims to investigate the relationship between the mechanism to improve corporate governance namely board effectiveness and the cost of debt in an emerging market. As we aim to explore the relationship between cost of debt and board effectiveness, we select corporation in Thailand as our sample because the businesses in Thailand are major debt-financing. Hence, our sample include listed firm in Stock Exchange of Thailand between 2007 and 2016. Our main findings support the sub-optimal investment hypothesis in that improved board effectiveness is associated with higher cost of borrowing. In addition, we find that the number of board member-board size, the number of board meeting, and the percentage of non-executive on audit committee play are positively associated with the cost of debt financing. Furthermore, we perform two-stage-least square (2SLS) to ensure that our results are far from endogeneity issue.