• Journal of Korean Society of Industrial and Systems Engineering
• /
• v.33 no.4
• /
• pp.130-137
• /
• 2010

This paper analyzes the main factors affecting user selection of a small-sum electronic payment system using survey data of 396 users. Several findings emerge. First, users consider three pillars and eight factors in adopting a new system : system features(stability, security, and flexibility), transaction cost(payment commission and settlement period), and financial capability of provider(stability of financial structure, risk management capability, and funding capability). Second, the stability of the financial structure of the system provider is the most important factor to user acceptance of a new e-payment system. Users tend to consider uncertainty risk more seriously than transaction cost. This reflects the reality that electronic payment system service industry has not fully fledged yet. Third, some moderating effects exist according to payment methods and business usages. As for payment methods, speedy settlement cycle for wired/wireless phone payment, system stability for credit card and account transfer payment, and security for advance payment means are crucial factors. As for business usages, the stability of financial structure for online game content, system stability for music and video content, proxy payment commission for e-learning content, flexibility of the payment system for digital adult content, and security for public services are decisive ones.

• Journal of Electrical Engineering and Technology
• /
• v.13 no.1
• /
• pp.51-59
• /
• 2018

Despite the advantages of energy arbitrage using energy storage systems (ESSs), the high cost of ESSs has not attracted storage owners for the arbitrage. However, as the costs of ESS have decreased and the price volatility of the electricity market has increased, many studies have been conducted on energy arbitrage using ESSs. In this study, the existing two-period model is modified in consideration of the ESS cost and risk-free contracts. Optimal investment strategies that maximize the sum of external effects caused by price changes and arbitrage profits are formulated by market participants. The optimal amounts of ESS investment for three types of investors in three different market structures are determined with game theory, and strategies in the form of the mixed-complementarity problem are solved by using the PATH solver of GAMS. Results show that when all market participants can participate in investment simultaneously, only customers invest in ESSs, which means that customers can obtain market power by operating their ESSs. Attracting other types of ESS investors, such as merchant storage owners and producers, to mitigate market power can be achieved by increasing risk-free contracts.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.12 no.4
• /
• pp.1940-1946
• /
• 2011

In this paper, we propose a method of schoolzone safety to the protection and management of accident and crime of school circumstance that it is increased recently. Hence, sensor network based intelligent monitoring module must be considered for schoolzone safety. It is not simple CCTV monitoring, but it means that the ability extension is proposed to monitor the dangerous situation for the risk management. Hence, this paper proposes the design of monitoring module considering various danger situations that can be occurred around the school.

• Journal of Families and Better Life
• /
• v.20 no.5
• /
• pp.149-166
• /
• 2002

In this study, 1 have analyzed the state of the use of information technology by the at-risk children who are residing in Husan metropolitan area. The ultimate goal of this study is to help ensure the healthy development of the children and improve the quality of their lives in this information-oriented society. For this research, 1 surveyed 183 children living in an institution or a low-income family in Busan metropolitan area. The survey questionnaire was designed to obtain information on the respondents, socio-demographic characteristics, computer-related conditions of the immediate and social environments, patterns of computer and Internet use, their experience and degree of so called, Net-generation syndrome, Internet addiction disorder, changes in social and familial life caused by Internet use, and exposure to pornographic materials. The results show that 95.9 % of at-risk children in Husan own a computer, 60.9 % of those computers being Pentium Ⅲ. A majority of the children (74.9 %) are connected to Internet at a high-speed, using such devices as LAN, ADSL or cables. About seventy-six percent of the children have used a PC and Internet less than two years. In other words, a majority of them have not used those for a long period of time. The main results of the research are summarized in the following: There is a significant difference among at-risk children in terms of experiences in computer and Internet use according to their grade levels. There is a gender difference in the amount of time spent on computer and Internet. Boys spend more time every week on computer and Internet than girls do. There is a significant difference in the pattern of computer and Internet use, according to the type of their risk, and grade level. The so-called 'Net Generation Syndrome' is not serious in this group. A majority of the at-risk children think that Internet is more interesting than TV. They hardly shop on Internet, and they don think the advertisements on Internet are a serious problem. Also, unlike many people assumptions, their desire to communicate through on-line chatting was very low. They do not tend to buy computer game programs, and Internet Addiction Disorder was not pronounced among them. The at-risk children rarely had an exposure to pornographic materials in the cyber space. However, the exposure was more frequent for institutionalized children than children in low-income families. These results point to a need for a policy to improve the welfare of at-risk children and guarantee their right to information.

• Journal of the Korea Convergence Society
• /
• v.10 no.9
• /
• pp.273-281
• /
• 2019

This study aimed to qualify the amount of movement during game-based training and competition by using a GPS and to identify the non-contact injury risk in lower extremities for female field hockey enrolled in Korean national team. A total of 52 players were participated in this study and their GPS data collected during training and competition were averaged for 1 week and 4 weeks. And then, an injury risk in lower extremities was calculated for each category of the amount of movement in GPS variables that were related to non-contact injury. In forwards, the injury risk was the lowest in the moderate-low category of total distance covered and repeated high-intensity effort bout and the high category of high intensity distance for 1 week, but the risk decreased as the amount of high intensity distance increased for 4 weeks. In midfielders, the injury risk was the lowest in the low category of total distance covered, high intensity distance, repeated high-intensity effort bout and deceleration bout for 1 week.

• Journal of the Korean Operations Research and Management Science Society
• /
• v.38 no.2
• /
• pp.159-178
• /
• 2013

We present a model, combining servitization decision and a conventional two-sided market approaches, to understand expected outcomes and current market situations. We suppose an individual manufacturer participates in multiple platforms and decides whether to initiate servitization by considering latent profitability and risk. The analytical results from the model show that increasing competition within servitized companies lead to a servitization equilibrium, wherein the ratio of servitized companies in a market is stable, due to a gradual decline in relative benefits compared to non-servitized companies. This holds even in the case that the number of customer is increasing along the diffusion of servitization, under some restricted conditions.

• Korean Journal of Computational Design and Engineering
• /
• v.9 no.2
• /
• pp.148-157
• /
• 2004

Interactive simulators that simulate mechanical systems are being developed for the purpose of performance evaluation of product design, replacement of physical training, and entertainment game. Use of flight simulator is increasing to reduce risk and cost of physical training, and we need virtual environment which covers large area terrain. We need a method that can reduce development cost and construction time of virtual environment that simulate the real environment. There have been attempts to link GIS or remote sensing field with virtual reality. This paper examines a method that helps to construct virtual environment, and attempts to link geographic information with virtual reality. A construction method of virtual environment based on digital map and satellite image has been studied.

• The Transactions of The Korean Institute of Electrical Engineers
• /
• v.59 no.12
• /
• pp.2150-2156
• /
• 2010

In this paper, we investigate how an electricity capacity market design may encourage generators to exaggerate their available capacity. In order for an analytical approach, a two player game model is introduced. We focus on two pure strategy Nash equilibria: an equilibrium at which generators offer their true capacities, and an equilibrium at which generators offer exaggerated capacities. The latter case is caused by asymmetries of information between players and so called 'moral hazard' in terms of the economics literature. This paper shows that, considering practical electricity markets, the moral hazard case is highly probable. Moreover, it is shown that, with the considered capacity market design in the real world, the better the electricity energy market performs, the higher the risk of moral hazard becomes.

• Journal of Korea Multimedia Society
• /
• v.12 no.10
• /
• pp.1457-1465
• /
• 2009

In MMORPG development process, spreadsheet based data management has advantages in the handling of functions and analysis of large data set. But it has limitations in inserting, deleting, searching and relational management of that. In this paper, we proposed the spreadsheet based tool model for large data set for MMORPG development. Our system can reduce the risk of data management failure in MMORPG development process and improve the efficiency of data handling in the large-scale team.

• Proceedings of the KIEE Conference
• /
• summer
• /
• pp.701-703
• /
• 2004

Although the electricity market structure worldwide may be different in kinds, there generally exists long-term forward market and short-term spot market. Particularly, the bilateral contract in long-term forward market fixes the price between a genco and a customer so that the customer can avoid risks due to price-spike in spot market. The genco also can make an efficient risk-hedge strategy through this bilateral contract. In this paper, we propose a new mechanism for evaluating the optimal bilateral contract price using game theory. This mechanism makes a customer reveal his/her own willingness to purchase electricity so that a fair bilateral contract price can be derived.