• Journal of the Korean Operations Research and Management Science Society
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• v.39 no.4
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• pp.115-136
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• 2014

The game industry has grown steadily and the online game has become one of the most attractive game segments for its remarkable growth. Customer management in the online game industry, however, has received little attention from the academic field. The purpose of this study is to analyze the drivers of customer defection in the online game setting and suggest not only theoretical but also managerial insights into increasing customer retention rates. Prior to empirical analysis, the authors hypothesized that 3 variables of interests (Learning, Playing, Achievement) would explain the customer defection according to preceeding researches. To demonstrate these hypotheses, the authors obtained data from one of the biggest game publishers in Korea, and the empirical analysis model was developed considering context of research settings. The results of analyses provide the following insights. First, the key behavioral variables of Learning, Playing, and Achievement play substantial roles in explaining the customer defection. Next, the effects of these variables vary between customer types: novice and experienced customers. The defection decisions by novice customers are predicted by all key behavioral variables and Playing serves as the most influential indicator of the defection decisions. However, experienced customers are influenced by Playing and Achievement, while Learning has no impact on the defection decisions. Finally, the authors investigated hypothetical customer retention strategies, using the empirical results. The market outcomes indicate that the customer retention strategies work well with novice customers and it is hard-to-impossible to prevent experienced customers from defection using their behavioral data. These findings together deliver several meaningful insights to management as follow. First, the management should support customers to get involved in Learning activities at the very first stage. Second, customer's Achievement and appropriate compensation for it would work as defection barriers. Last, to optimize the outcomes of firm's marketing investments, it is better to focus on retention of novice users not experienced ones.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.12 no.20
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• pp.123-138
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• 1989

The primary objective of the agency research in the game theory lives in the maintenance of Pareto is optimal condition for the optimal incentive contract. The basic concepts which are related to this objective are reviewed in connection with the general assumptions to model it, the moral hazard and adverse selection which arised from the information asymmetry, and finally the problem of risk distribution. The demand for auditing and the role of auditor have been addressed by ASOBAC. Issues which an auditor is explicitly introduced in a principal-agent framework have been addressed in this paper. These issues must be confronted to appropriately with the auditor, and to achieve an adequate understanding of optimal confronting arrangement with the auditor. The first step in introducing an auditor into this analysis is to examine the game-theoretic foundation of such a expended agency model. The Mathematical program formulated may not yield solution that are resonable. This arises because the program may call for the auditor and manager to play dominated Nash equilibra in some subgame. The nontrivial natures of the subgame implies that randomized strategies by the auditor and manager nay be of crucial importance. The possibilities for overcoming the randomized strategy problem were suggested; change the rule of the game and or impose covexity condition. The former seems unjustifiable in on auditing context, and the latter promising but difficult to achieve. The discussion ended with an extension of the revelation principle to the owner manager-auditor game, assuming strategies. An examination of the restriction and improvement direction of the basic concept of agency theory was addressed in the later part of this paper. Many important aspects of auditor incentives are inherently multiple-agent, multiple-period, multiple-objectine, phenomena and require further analyses and researches.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.18
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• pp.7553-7558
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• 2014

The Piwi subfamily comprises two argonaute (Ago) family proteins, which are defined by the presence of PAZ and Piwi domains, with well known roles in RNA silencing. Hiwi, a human Piwi subfamily member, has been shown to play essential roles in stem cell self-renewal and gametogenesis. Recently, accumulating reports have indicated that abnormal hiwi expression is associated with poorer prognosis of multiple types of human cancers, including examples in the breast. However, little is known about details of the oncogenic role of hiwi in breast cancers. In present study, we confirmed overexpression of hiwi in breast cancer specimens and breast cancer cell lines at both mRNA and protein levels. Thus both RT-qPCR and Western blot data revealed significantly higher hiwi in intratumor than peritumor specimens, overexpression being associated with tumor size, lymph node metastasis and histological grade. Hiwi overexpression was also identified in breast cancer cell lines, MDA-MB-231 and MCF-7, and gain-of-function and loss-of-function strategies were adopted to identify the role of hiwi in the MCF-7 cell growth. Results demonstrated that hiwi expression in MCF-7 cells was significantly up- or down-regulated by the two strategies. We next evaluated the influence of hiwi overexpression or knockdown on the growth of breast cancer cells. Both cell count and colony formation assays confirmed promoting roles of hiwi in MCF-7 cells, which could be inhibited by hiwi specific blockage by siRNAs. In summary, the present study confirmed overexpression of hiwi in breast cancer specimens and breast cancer cell lines, and provided e vidence of promotion by hiwi of cell growth. The results imply an oncogenic role of hiwi in breast cancers.

• STI Policy Review
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• v.5 no.1
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• pp.1-33
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• 2014

Despite a commonly held belief that standards obstruct innovation, recent research shows that they can actually play critical roles in supporting various activities of technological innovation. Thus, providing an innovation-friendly environment through standardization has been gaining much attention in recent years; however, there is as yet limited understanding, due to complex dynamics and high uncertainties associated with innovation, as well as a variety of different types and functions of standards with various stakeholders involved. The problem becomes even more challenging for standardization in highly complex systems, such as Information and Communication Technology (ICT) systems, where a large number of domains and components are involved, along with various types of stakeholders. In order to deal with such complexity and variations, a systematic approach of standardization roadmapping has been used in many technology-leading countries as a strategic policy tool for supporting effective management of standardization. Despite its wide adoption, the current understanding of standardization roadmapping is somewhat limited, leaving significant challenges for policymakers and standards organizations in terms of how to structure and manage roadmapping exercises, and how the government should get involved. In this regard, the current research explores existing standardization roadmaps in various contexts related to ICT systems (ICT in Korea, Smart Grid in the US, and electromobility in Germany), as there is a particular need for systematic development of strategies for such complex systems of ICT. Focusing on various aspects of standardization roadmapping exercises such as their structures, processes, and participants, their common features and key characteristics are identified. Comparing these roadmaps also reveal distinct differences between standardization roadmapping approaches adopted by different countries in different contexts. Based on lessons learnt from existing practices, the study finally provides insight for the Korean ICT standards community on the ways in which their standardization roadmapping approach can be improved to support anticipatory management of standardization activities more effectively. It is expected that the current research can not only provide increased understanding of standardization roadmaps, but also help policymakers and standards organizations to develop more effective strategies for supporting innovation through the systematic management of standardization.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.20
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• pp.8641-8645
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• 2014

The rising trend of breast cancer both in developed and developing countries is a real threat challenging all efforts to screening, prevention and treatment aspects to reduce its impact. In spite of modern preventive strategies, the upward trend of breast cancer has become a matter of great concern in both developed and developing countries. Chittaranjan National Cancer Institute is a premier regional cancer institute in eastern region of India catering to a large number of cancer patients every year. A pilot case control study of fifty breast cancer patients and 100 matched controls was conducted during 2013 to evaluate the effects of habitual factors like working in night shift, not having adequate sleep, and not sleeping in total darkness on breast cancer of women. The study revealed that not sleeping in total darkness was associated with higher odds of outcome of breast cancer of women. This positive correlation can play a vital role in formulation of preventive strategies through life style modification.

• The Korean Nurse
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• v.29 no.5
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• pp.46-53
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• 1991

In the past, management had been done over nurses rather than nursing and this brought the existence of general manager and as a result, nurse-manager's position and role are being threatend. For the up-bringing of nursing to firm professional recognition in the 21st century, it is firmly believed that nursing managers are to be in the position to play the role of general manager with professional qualifications; personal qualities and exact understandings on the role and function of each tier group under her/his management. 124 top(3 nursing superintendents), middle-range(23 supervisors) and unit managers(98 head-nurses) from 3 university hospitals in Seoul were interviewed in order to investigate their belief in the role, professional qualifications, personal qualities as well as the strategy for the development of their leadership qualities. The frame of reference for the interview were developed by the researcher in reference to relevant literatures. It was the common belief that qualifications o[ top-managers and mid-managers require an educational background of master's preparation or higher and clinical career for at least 15 years for top-managers and 5 -10 years for mid-managers. The personal qualities required by nurse managers include; leadership, initiative, judgement, self-confidence, flexibility, open-mindedness and strong motivation. Achievment-orientedness would greatly help them become excellent managers. On the other hand, [or more effective management, managers of each teir group are to fully understand their role and perform "their job responsibilities ie. Top managers are supposed to study with emphasis on organization, function and conceptual s~ill while mid-managers concentrate their effort on the development of skills for direction, guidance and human relationship. Unit managers also supposed to have abilities to manage their function with emphasis on development of clinical performance skill, for direction on operative aspects. The strategies for the development of leadership qualities include program-planning at individual instutional level as well as local, national and international level. Nurse-managers are to be motivated and encouraged to participate in the programs in order to effectively communicate within tier groups.oups.

• Journal of Korea Spatial Information System Society
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• v.7 no.3 s.15
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• pp.3-11
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• 2005

There are not enough information and service in current e-government practice because it only relier on text based information services. To make e-government more attractive and successful, scope of information and service should be broaden. To do so, GIS is necessary in the development process of e-government. This paper aims at exploring theories and technologies related to e-government and suggesting strategies for developing GIS based local e-government. In this paper, we particularly pay attention to the role of GIS for local e-government. Since many of local government data has spatial components, we believe that GIS would play a crucial role in developing local e-government. Thus, this paper tries to examine how GIS contribute to successful implementation of e-government. Then, it attempts to build a developmental model for GIS based e-government. Finally, it suggests strategies and policy measures for each development stage.

• International Journal of Control, Automation, and Systems
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• v.2 no.4
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• pp.463-474
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• 2004

Game theory is a method of mathematical analysis developed to study the decision making process. In 1928, Von Neumann mathematically proved that every two-person, zero-sum game with many pure finite strategies for each player is deterministic. In the early 50's, Nash presented another concept as the basis for a generalization of Von Neumann's theorem. Another central achievement of game theory is the introduction of evolutionary game theory, by which agents can play optimal strategies in the absence of rationality. Through the process of Darwinian selection, a population of agents can evolve to an Evolutionary Stable Strategy (ESS) as introduced by Maynard Smith in 1982. Keeping pace with these game theoretical studies, the first computer simulation of coevolution was tried out by Hillis. Moreover, Kauffman proposed the NK model to analyze coevolutionary dynamics between different species. He showed how coevolutionary phenomenon reaches static states and that these states are either Nash equilibrium or ESS in game theory. Since studies concerning coevolutionary phenomenon were initiated, there have been numerous other researchers who have developed coevolutionary algorithms. In this paper we propose a new coevolutionary algorithm named Game theory based Coevolutionary Algorithm (GCEA) and we confirm that this algorithm can be a solution of evolutionary problems by searching the ESS. To evaluate this newly designed approach, we solve several test Multiobjective Optimization Problems (MOPs). From the results of these evaluations, we confirm that evolutionary game can be embodied by the coevolutionary algorithm and analyze the optimization performance of our algorithm by comparing the performance of our algorithm with that of other evolutionary optimization algorithms.

• Journal of Korea Port Economic Association
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• v.26 no.4
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• pp.269-288
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• 2010

21 C is called the age of Culture and it is underlined in all the Areas of Human lifes. Among all activities, Culture oriented Thinking and activities and strategies through and for Culture establishing are emphasized. As Sea may appear as a image of longing and challenge for the unknown world, Port is understood as a link which connect Sea and Land. Sea, Island and Port are the basis of human lifes, economic working areas and communication spaces with nature. Sea and Port have been changed in accordance with human History as the space of Life, Work, Play and Imagination. The Maritime activities has been developed as the type of a Culture, including various diversities according to the time and space. This Paper suggested a definition of Maritime Culture and Theoretical review and groped introduction and strategies and countermeasures for expansion of systematic Maritime Culture. Maritime Culture not only enhance the quality of Citizen life but also contribute the progress of National economy increasing the quality of Culture, Turism and Environment and the expectation of it has been enlarged. It is needed to introduce and expand Maritime Culture systematically through theoretical framework suggested by this paper, and additional research may be necessary for the detailed solutions and countermeasures.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.5
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• pp.294-304
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• 2016

This study aims at identifying the development strategies for capacity building of intermediary agencies from the survey and analysis of intermediary agencies in the private sector which play an important role in the economic development of Chungnam province. From the review of the literature, we defined the concept of intermediaries as an institute or program which builds and maintains the proper relationship among the various actors. In order to determine the current situation of intermediary agencies and their roles in Chungnam province, we selected nine private industrial institutes and carried out a questionnaire and interview survey. It was identified that they have very limited knowledge of the role of intermediaries, while mainly focusing on the traditional function of lobbying groups. Therefore, a policy needs be developed to allow them to participate in regional development projects, in order to improve their capability to facilitate network activities for regional economic development.