• Journal of Communications and Networks
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• v.18 no.4
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• pp.610-618
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• 2016

A green cognitive radio network (CRN), characterized by base stations (BSs) that conserve energy during sleep periods, is a promising candidate for realizing more efficient spectrum allocation. To improve the spectrum efficiency and achieve greener communication in wireless applications, we consider CRNs with an long term evolution advanced (LTE-A) structure and propose a novel energy-saving strategy. By establishing a type of preemptive priority queueing model with a single vacation, we capture the stochastic behavior of the proposed strategy. Using the method of matrix geometric solutions, we derive the performance measures in terms of the average latency of secondary user (SU) packets and the energy-saving degree of BSs. Furthermore, we provide numerical results to demonstrate the influence of the sleeping parameter on the system performance. Finally, we compare the Nash equilibrium behavior and social optimization behavior of the proposed strategy to present a pricing policy for SU packets.

• Asia-Pacific Journal of Business
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• v.9 no.3
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• pp.71-82
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• 2018

This study verifies whether the sustainable tax strategy provides unique information on earnings persistence and brings about the difference of value relevance of accounting information. Sustainability is measured by the 5-year coefficient of variation in cash ETR, such as in McGuire et al.(2013), which measures variability in long-term performance of tax avoidance. The value relevance of accounting information in this study is modified by the Ohlson model(1995), which explains the value of the firm by using accounting information such as net assets and net income and other non-accounting information. The samples of this study are the firms listed on the securities market from 2004 to 2015 and the final samples are 3,133 firm-year. The results of this empirical analysis show that the value relevance of accounting information increases as firms have long-term and sustainable tax strategies. Most of the prior studies on tax strategies have examined the tax minimization strategy that minimizes the tax cost. However, this study is different in that the sustainability of the tax strategy affects the value relevance of accounting information. The results of this study will be useful for the users to make decision using the value relevance of accounting information.

• Journal of Korea Trade
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• v.24 no.3
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• pp.55-72
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• 2020

Purpose - In this paper, we provide recommendations for Korea's long-term direction and strategic measures to attract inward foreign direct investment (FDI) in response to Japan's export regulations. In doing so, we analyze the current situation and characteristics of trade between Korea and Japan, focusing on the parts and materials industry, which is particularly affected by Japan's trade regulations. Design/methodology - Based on the analysis of five successful inward FDI cases (e.g. Toray, IGK, Delkor, GlobalWafers, DuPont) and statistic trend review in the parts and materials industry, we consider various factors pertaining to successful inward FDI in Korea and propose valuable investment attraction strategies. Findings - For a successful investment attraction strategy, we studied some statistical trends in the internal and external environments of the parts and materials industry and successful investment attraction cases in Korea. We have found that in order to increase the probability of success in attracting investment, we need a mid-to long-term strategy considering multiple factors such as "Production-oriented, Demand-linked, Global Value Chain (VGC) linked, and Policy-linked investment attraction." Originality/value - We suggest several specific measures and important strategic implications for the Korean government and firm's managers to attract inward FDI successfully.

• The Korean Journal of Health Service Management
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• v.2 no.1
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• pp.125-136
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• 2008

Government came to enforce long-term care insurance system in preparation for the rapid aging society. Whether this system is successful or not depends on the professionalism of long-term care-givers who are professional population in charge of care service. Currently in the early stage of enforcement, such problems as a race cutting fee resulted from numerical increase of educational facilities, insolvent operation, degradation of education level resulted from unprofessional instructor, are pointed out. As a mean of manpower-training on long-term care insurance system, this study is to research public-private-university network model of the Academy of Continuing Education attached to Ko Sin University which is the case of Yong Do Gu Busan city. Networking between the vision and development strategy of Yong Do Gu on continuing education city, education system on community manpower-training supported by Ko Sin University, and service field of welfare for the elderly can not only contribute to the professionalism of long-term care-givers but also play an ideal role in manpower-utilization and arrangement of community. Through this networking, high quality of education level and circumstance, using the existing infra, manpower-training and utilization for continuing education of Yong Do Gu can be accomplished. Additionally, the connection with facilities related with welfare for the elderly can contribute to professionalism and accountability of manpower-networking.

• IE interfaces
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• v.23 no.4
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• pp.300-310
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• 2010

This paper is about an optimal investment portfolio strategy. Financial data of stocks, bonds, and savings from January 2. 2001 through October 30. 2009 were utilized in order to suggest the optimal portfolio strategies. Fundamental analysis and technical analysis were used in stocks-related strategy, whereas passive investment strategy and active investment strategy were used in bond-related strategy. The score is assigned to each stock index according to the suggested strategies and set trading rules are based on the scores. The simulation has been executed about each 29,400-portfolios and we figured out with the simulation result that 26.75% of 7,864 portfolios are more profitable than average stock market profit (22.6%, Annualized). The outcome of this research is summarized in two parts. First, it's the rebalancing strategy of portfolio. The result shows that value-oriented investment(long-term investment) strategy yields much higher than short-term investment strategies of stocks or active investment of bonds. Second, it's about the rebalancing cycle forming the portfolios. The result shows that the rate of return for the portfolio is the best when rebalancing cycle is 12 or 18 months.

• Journal of Korea Port Economic Association
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• v.20 no.1
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• pp.21-42
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• 2004

This paper addresses the operation, problems, and development policy of Gwangyang Port, Korea. This paper aims to analyze the operation condition and problems of Gwangyang Port and suggest long-term policies for developing Gwangyang Port as a logistic hub in northeast period. It is made up of three main sections: the operation, problems, and forecast of freight volumes; analysis of operational results of Gwangyang Port; development strategies of Gwangyang Port as a Logistics Hub. This paper was mainly based on a review of current papers/reports, an analysis of secondary data, and questionnaire survey. The major development strategies identified consisted of expansion regular service sea-route, formation of inter-modal transportation system, strengthening of port sales for Gwangyang port's recognition, securing operation-profits by fixed cargo volume, and promotion of free tread zone.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.33 no.4
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• pp.10-22
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• 2010

The first full-scale u-City operation has started in Dongtan u-City. As local cities take over and operate the u-City, unexpected issues arise such as securing the budget of operating costs and self-providing the costs with business models utilizing the u-City assets. The paper presents a strategy for solving these issues. The strategy provides a foundation(infrastructure) for long-term operation models which may reduce the long-term operating costs. In order to establish the economic operating framework of u-City, suggested are some cost-reduction models based on the operating costs structure. For each model, a base framework with comparative analysis of operating costs is provided. With these models, each u-City may select a relevant model according to the characteristics of it. We hope that the framework provides the foundation for efficient and sustainable u-City operations.

• Clinical and Experimental Pediatrics
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• v.58 no.3
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• pp.77-83
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• 2015

Relative to a fetus of the same gestational age, very low birth weight (VLBW) infants are more likely to be underfed and to undergo growth restriction during their early hospital stay. The current trend towards "early and aggressive" nutritional strategies in VLBW infants aims to overcome the early nutritional deficiency and thereby boost postnatal catch-up growth, simultaneously improving long-term neurodevelopmental outcomes. Although the minimum starting amino acid (AA) dose to prevent negative nitrogen balance is well established, the upper limit and the rate of increase of early AA doses are controversial. Most randomized controlled trials show that early and high-dose (target, 3.5 to 4.9 g/kg/day) AA regimens, with or without high nonprotein calories, do not improve long-term growth and neurodevelopment. High-dose AA supplementation may lead to early metabolic disturbances and excessive or disproportionate plasma AA levels, particularly in infants of very low gestational age. Further large studies are needed to clarify the optimal strategy for early administration of parenteral AA doses in VLBW infants.

• Korean Journal of Psychosomatic Medicine
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• v.3 no.1
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• pp.72-80
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• 1995

Because the origins of stress are various, complex, and often indirectly-causing, reactions to stress are also various according to it's psychopathologies and mechanisms. For a proper management of stress, first of all accurate evaluation and diagnosis must be done. Then, treatment against the stress also can be considered, if necessary. In case of extreme stress, psychotropic drugs such as short-term anxiolytics or antidepressants can be used according to it's specific target symtoms. But long-term treatment of stress must be directed by increasing the individual's usual coping strategy or decreasing the externally causing stresses. Reactions to stress and drug interactions. which are not the whole of the biologic treatment strategy, are very important As a results, in our discussions, we ought to describe the issues by focusing the interactions between the drug and it's reaction to stress rather than the reaction to stress or drug itself and aimed at helping the proper treatment against the stress.

• Journal of Korean Institute of Industrial Engineers
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• v.30 no.3
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• pp.241-249
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• 2004

By committing to a long-term replenishment contract, suppliers can mitigate the pressure to find new customers and afford to charge a discounted price to buyers seeking to lower their purchasing costs. In this paper, we develop an analytical model from buyer's perspective for the contracting process to investigate the buyer-supplier interactions. Based on the developed model, we propose an algorithm to derive optimal strategy for the contract. We consider a system with a single buyer and a supplier in a situation where the buyer's inventory is controlled by (R, S) policy under VMI setting. According to the contract, the supplier should replenish the buyer's inventory up to a fixed level every R times during a specified period. The buyer purchases any deficient amount from a spot market at a higher price. We show by computational experiment that our proposed algorithm finds the global optimum solution.