• Environmental and Resource Economics Review
• /
• v.32 no.2
• /
• pp.77-105
• /
• 2023

This paper investigates the management stability of KOSPI-listed energy public enterprises from the perspective of median voter theory. We analyze the profitability and stability of five energy public enterprises during the period 2011~2022, and conduct an empirical analysis to determine whether they are related to the preferences of median voters who can represent the general public. Our analysis of the profitability and stability of the energy public enterprises shows that the stability of their has been deteriorating in recent years. The results of the empirical analysis also show that the management stability of the energy public enterprises is related to the preference of median voter. Specifically, they indicate that when the median voter's income is smaller than the average income, the profitability of the utility decreases and the debt ratio increases. This paper suggests that from the median voter's point of view, excessive utility and energy bills may strengthen the incentives for governments and politicians to suppress rate increases, leading to lower profitability and higher debt for public enterprises.

• Korea Journal of Hospital Management
• /
• v.10 no.4
• /
• pp.75-97
• /
• 2005

The research objective is to empirically investigate the compensation packages maximizing the utilities of internal customers by applying the market segmentation theory. Data was collected from four Korean hospitals in Seoul, Busan and Gyunggi-do. The research is designed to seek the compensation package maximizing the utility of doctors by mixture regression model, which has been applied as latent structure and other type of finite mixture models from various academic fields since early 1980s. The mixture regression model shows the optimal segments number and fuzzy classification for each observation by EM(expectation-maximization algorism). The finite mixture regression model is to unmix the sample, to identify the groups, and to estimate the parameters of the density function underlying the observed data within each group. The doctors were segmented into 5 groups by their preference for the compensation package. The results of this study imply that the utility of doctors increases with differentiated compensation package segmented by their preference.

• The Journal of Fisheries Business Administration
• /
• v.27 no.1
• /
• pp.57-65
• /
• 1996

This paper is concerned with the development of ameliorating inventory models. The ameliorating inventory is the inventory of goods whose utility increases over the time by ameliorating activation. The term ameliorating inventory is used in this paper at least, since the terminology is not standard well known. This study is performed according to areas; one is an economic order quantity(EOQ) model for the items whose utility is ameliorating in accordance with Weibull distribution, and the other is a partial selling quantity(PSQ) model developed for selling the surplus inventory accumulated by ameliorating activation. The proposed models cannot be solved directly in a closed form, thus we used a computer program and a graphical solution method to obtain the optimal ordering and setting quantity in this paper. Numerical examples to illustrate the effect of ameliorating rate on inventory polices are shown at the end of this paper.

• Proceedings of the Korean Operations and Management Science Society Conference
• /
• 1996.10a
• /
• pp.53-56
• /
• 1996

The conventional inventory models are concerned with the items of which utilities and amount of numbers are constant over time. But in practice the items in inventory systems are increasing or decreasing. This study is concerned with the development of ameliorating inventory models. The ameliorating inventory is the inventory of goods whose utility increases over the time by ameliorating activation. The term ameliorating inventory is used in this paper at least, since the terminology is not standard well known. This study is performed according to areas; one is an economic order quantity(EOQ) model for the items whose utility is ameliorating in accordance with Weibull distribution, and the other is a partial selling quantity(PSQ) model developed for selling surplus inventory accumulated by ameliorating activation. Computer programs are developed to obtain the optimal ordering and selling quantity. Numerical examples to illustrate the effect of ameliorating rate on inventory polices are shown at the end of this paper.

• Journal of Advanced Navigation Technology
• /
• v.6 no.3
• /
• pp.211-222
• /
• 2002

This paper describes the utility of satellite sensors of the missile defense system using the estimation theory. The inherent flight characteristics of the missiles give the limitations in the response time and the countermeasures. In this point, the early warning and surveillance satellites are important. Using the Extended Kalman Filter, it is analysed LPU and MLU in DSP and SBIRS satellites, and presented the quantitative uncertainties of state estimates of non-rotational DSP compare to the rotating one.

• KSII Transactions on Internet and Information Systems (TIIS)
• /
• v.5 no.3
• /
• pp.542-559
• /
• 2011

Most game-theoretic works of Aloha have emphasized investigating Nash equilibria according to the system state represented by the number of network users and their decisions. In contrast, we focus on the possible change of nodes' utility state represented by delay constraint and decreasing utility over time. These foregone changes of nodes' state are more likely to instigate selfish behaviors in networking environments. For such environment, in this paper, we propose a repeated Bayesian slotted Aloha game model to analyze the selfish behavior of impatient users. We prove the existence of Nash equilibrium mathematically and empirically. The proposed model enables any type of transmission probability sequence to achieve Nash equilibrium without degrading its optimal throughput. Those Nash equilibria can be used as a solution concept to thwart the selfish behaviors of nodes and ensure the system stability.

• The Transactions of the Korean Institute of Power Electronics
• /
• v.7 no.1
• /
• pp.41-47
• /
• 2002

In this paper, a new line-commutated SCR inverter for renewable power generation system is proposed. The proposed inverter system includes a 6-pulse SCR inverter and an auxiliary circuit. By the proper operation of the auxiliary circuit, the pulse number of the inverter system is increased and the output voltages and currents harmonics are significantly reduced. Analysis, control and simulation for 24-pulse operation of the proposed scheme is Presented and the experimental results from a laboratory Prototype verify the proposed theory.

• Journal of Korean Academy of Nursing
• /
• v.45 no.6
• /
• pp.919-927
• /
• 2015

Purpose: Effective transitional care is needed to improve the quality of life in older adult patients with chronic illness and avoid discontinuity of care and adverse events. The aim of this article is to provide an overview of the key features, broader implications, and the utility of Meleis' transition theory intended for the transitional care of older adults with chronic illnesses. We present the role of nurse in the context of transitional care and propose future directions to increase the quality of nursing care. Methods: The online databases Cumulative Index of Nursing and Allied Health Literature, MEDLINE, and Science Direct were searched for relevant literature published since 1970 along with textbooks regarding nursing theory. Results: An evaluation of the usefulness of transition theory based on transitional care in older adult patients with chronic illnesses is provided. Healthy transition should be the expected standard of nursing care for older adults across all healthcare settings. Conclusion: Nurses need to contribute to the development of transitional care for vulnerable populations; however, transition theory needs to be enhanced through additional theoretical work and repeated evaluations of the applicability in areas of transitional care.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.32 no.4A
• /
• pp.373-378
• /
• 2007

In this paper, the Game Theory based power control for OFDM system is studied, which has attained intensive interest as a core artificial intelligent technology for Cognitive Radio and its efficiency is evaluated using performance metrics such as system throughput and fairness. Utility Function for joint user centric and network centric power control is defined and simulation results show that game theory based power control is far better than closed loop power control. The contribution of this paper is to formalize the game theory based power control toward the Cognitive Radio that recognizes and adapts to the radio communication environments.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.17 no.5
• /
• pp.671-679
• /
• 2016

Bridges, which constitute one of the key facilities in a social infrastructure, are easily accessed and used by users, so that keeping their performance above a certain level is essential. According to various cases in the U.S., Japan and Europe with a long construction history, it is expected that the maintenance cost of bridges in Korea will increase continuously in the future, so a rational decision making system based on engineering factors is necessary to optimize the performance of and maintain them by allocating the limited budget efficiently. This study is a preliminary basic study for the purpose of developing a common asset management system for managing all of the bridges and maintaining the level of service provided by them. The scope of this preliminary study is limited to bridges in urban areas. The bridge asset management system for bridges in urban areas, their level of service (LOS) and performance measure (PM) were developed by carrying out a workshop consisting of both experts and stakeholders. The analysis on the weights of the value and performance measure for each performance indicator was carried out by using the multi-attribute utility theory and the AHP method. In order to confirm the application of the weight of the performance measure and value of the performance indicator, six bridges in an example city were selected, LOS analysis was applied and its results were reviewed.