• Journal of Intelligence and Information Systems
• /
• v.15 no.3
• /
• pp.137-150
• /
• 2009

This paper proposes the hybrid heuristic method to apply the opportunity time to solve the vehicle routing and scheduling problem with time constraints(VRSPTW). The opportunity time indicates the idle time which remains after the vehicle performs the unloading service required by each customer's node. In this proposed heuristic, we add the constraints to VRSPTW model for the opportunity time. We also obtain the initial solution by applying the cost evaluation function to the insertion strategy considering the opportunity time. In addition, we improve the former result by applying the opportunity time to the tabu search strategy by swapping the customer's node. Finally, we suggest the construction strategies of initial routing which can efficiently acquire the nearest optimal solution from various types of data in terms of geographical condition, scheduling horizon and vehicle capacity. Our experiment show that our heuristic can get the nearest optimal solution more efficiently than the Solomon's I1 heuristic.

• Journal of the Korea Institute of Military Science and Technology
• /
• v.10 no.2
• /
• pp.148-151
• /
• 2007

The CF(Counter-fire) is neutralizing enemy's all command control systems and fire support elements. It will weaken a battle continuous ability and an intension to fight. At the beginning of the CF is obtaining locations of targets using various detection assets. CF command center processes acquired target information and send it to attacking equipments. The targets are classified into two classes, preplanned target and target of opportunity The target of opportunity is potential threaten, so it needs to take a immediate and exact process for determining location of target of opportunity. This paper proposes the real-time processing algorithm for offensive weapons to strike target of opportunity, and presents the result of its performance.

• Management Science and Financial Engineering
• /
• v.20 no.2
• /
• pp.13-25
• /
• 2014

We investigate an optimal retirement time and consumption/investment policy of a wage earner who expects to find a better investment opportunity after retirement by being freed from other work and participating fully in the financial market. We obtain a closed form solution to the optimization problem by using a dynamic programming method under general time-separable von Neumann-Morgenstern utility. It is optimal for the wage earner to retire from work if and only if his wealth exceeds a certain critical level which is obtained from a free boundary value problem. The wage earner consumes less and takes more risk than he would without anticipation of a better investment opportunity.

• Journal of Labour Economics
• /
• v.33 no.2
• /
• pp.27-52
• /
• 2010

This study, using Korean Time Use Survey 1999, analyzes how opportunity costs of maternal time affects the ways in which mothers allocate their time to market work/housework/child care/leisure. Opportunity costs include two kinds: hourly child care costs and log hourly wage rates. Results show that a unit increase in child care costs reduces market work but increases housework, child care, and leisure. The effects of log wage rates are opposite those of child care costs. The result that a unit increase in the log wage rates decreases child care lime is not consistent with a previous study for the United Stales. These results differed by mother's educational attainments. This study suggests that policy-makers should pay careful attention to the effects of various types of mother's opportunity costs on non-market time in promoting maternal employment.

• IE interfaces
• /
• v.18 no.2
• /
• pp.184-192
• /
• 2005

In recent research there has been intense interest in understanding how real option valuation (ROV) approaches might usefully complement conventional discounted cash flow (DCF) techniques. However, investment decision makers in a real world have been worried about adopting the ROV approaches mainly because of difficulty in technically understanding the theory of the ROV approaches as indicated by many researchers. With this difficulty in mind, we propose the opportunity cost model as another discrete-time model to value a deferral option. The main advantage of observing a real options value in terms of the opportunity cost concept is to provide a technique for practitioners to estimate a wide range of real options values without sticking to a financial option modelling. The fundamental ground for developing the opportunity cost model proposed in this paper lies in the work of dissecting the structure of the real options value into three categories: capital gain, expected opportunity loss, and expected opportunity gain. At the end of the paper, we will present a short illustrative example to demonstrate the applicability of the model.

• Journal of the Korean Regional Science Association
• /
• v.10 no.2
• /
• pp.17-29
• /
• 1994

This study attempts to examine the regional distribution and the locational pattern of leisure facilities at Kangnam-gu in Seoul. For the convenience of the analysis the facilities are classified into public and private sector and then the facilities are classified into 11 types: mineral spring resort, play ground, neighborhood park, swimming pool, gymnasium, bowling, pingpong, aerobic, golf practice, health, and billiard facilities. For the purpose data was collected from statistical yearbook in 1993 and lists of registered facility at department of living physics of Kangnam-gu office. The data of the density of facilities and the opportunity of facilities per facilities type and per region are analysed with the technology of GIS. Results may be summarized as follows. First of all, correlation between the results of Location-Allocation model and the results of Interaction model is very high. Secondly, on comparing the density of facilities with the opportunity of the facility use per eleven facility types, three discrete spatial pattems are found. The mineral spring resort facility type with the highest unbalanced density and opportunity of facility use is to be found. Play ground, neighborhood park, swimming pool, gymnasium, bowling, pingpong, and aerobic facility types have the high unbalanced density and opportunity of facility use. The golf practice, health, and billiard facility types have spatially balanced density and opportunity of facility use. Thirdly, as comparing the density and the opportunity of the facility use per 'dong' administration unit, the spatial patterns of the public and the private facilities are different in density of the facility use and otherwise two are similar in the opportunity of the facility use. Fourthly, patterns of facilities users have different charateristics based on facility use time, expense, residence, and access time and four regional patterns are to be found ; user favorable, facility profitable, user balanced, and unfavorable.

• Journal of the Korean Operations Research and Management Science Society
• /
• v.26 no.4
• /
• pp.83-97
• /
• 2001

Net Present Value (NPV) criterion has been the most widely used criterion to evaluate investment opportunities. However, the analysis based on the NPV criterion falls to consider the managerial flexibility of deferring decisions until major uncertainty is resolved. Recently, real options method attracted a lot of attention as a Powerful approach to address the problem. If investment decision is deferred, the value of the investment opportunity increases but opportunity cost increases at the same time. Therefore, it is important to decide the optimal timing how long the decision can be deferred. In this paper, we developed a model deciding the optimal decision timing. Using the real options approach, the model derived the optimal deferring time until a decision is made. Then, the model was applied to a Korean mobile telecommunications company who wants to invest on the wireless resale business. We believe that this model would be very useful to overcome the problem of NPV decision criterion. With this approach, we can make contingent decisions based on the observation of uncertainly resolutions.

• Proceedings of the KIEE Conference
• /
• 2005.07a
• /
• pp.751-753
• /
• 2005

In this raper, Economic value of reserve margin i.i presented by opportunity cost for Korean power system, and the level of compensation for spinning reserve that is necessary to operate power system stably is proposed. The generator that is giving up for opportunity to participate in energy market must take opportunity cost. it is relative to not only whole demand level but also marginal cost of each resource. In this paper, assume that all resource in Korea is equivalent to six generator for simulation. and we evaluate value of reserve in the time of high demand and low demand. Also we propose the way to improve a evaluation method by examine relationship between capacity payment and value of reserve.

• Proceedings of the Korean Statistical Society Conference
• /
• 2003.05a
• /
• pp.43-48
• /
• 2003

We consider a consumption and investment problem where an investor's investment opportunity gets enlarged when she becomes rich enough, i.e., when her wealth touches a critical level. We derive optimal consumption and investment rules assuming that the investor has a time-separable von Neumann-Morgenstern utility function. An interesting feature of optimal rules is that the investor consumes less and takes more risk in risky assets if the investor expects that she will have a better investment opportunity when her wealth reaches a critical level.

• Journal of the Health Care and Life Science
• /
• v.11 no.2
• /
• pp.381-391
• /
• 2023

This study analyzed the perception of equality of opportunity among young people in Korean society using data from the 1st, 2nd, and 4th supplementary surveys of the Korea Education and Employment Panel II (KEEP II). The direction of analysis is to explore whether family background and academic activities (career maturity, academic achievement) during high school, economic situation, social relationships, and level of personal competency during adolescence are linked to the perception of equal opportunity. The analysis method established a structural equation model with the perception of equality of opportunity as the final dependent variable and confirmed the causal relationship using the LISREL program. As a result of the analysis, it was confirmed that the factors affecting young people's perception of equality of opportunity are the economic situation at the time of youth and the level of personal competency. The results of the study confirm the awareness of equality of opportunity among young people entering Korean society, and are expected to be used as information needed to create a social foundation so that they can play a responsible role as members of society.