• Korean Business Review
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• v.20 no.2
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• pp.15-27
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• 2007

This paper analyzed the relationship between Housing Purchase Price volatility of Seoul and Housing Purchase Price volatility of local large city. Other studies investigates the effect on the observed volatility Observed volatility consists of fundamental volatility and transitory volatility. Fundamental volatility is caused by information arrival and transitory volatility is caused by noise trading. Fundamental volatility is trend component and is modelled as a random walk with drift. Transitory volatility is cyclical component and is modelled as a stationary process. In contrast to other studies, this study investigates the effect on the fundamental volatility and transitory volatility individually. Observed volatility is estimated by GJR GARCH(1,1) model. We find that GJH GARCH model is superior to GARCH model and good news is more remarkable effect on volatility than bad news. This study decomposes the observed volatility into fundamental volatility and transitory volatility using Kalman filtering method. The findings in this paper is as follows. The correlation between Seoul housing price volatility and Busan housing price volatility is high. But, the correlation between Seoul and Daejeon is low. And the correlation between Daejeon and Busan is low. As a distinguishing feature, the correlation between fundamental volatilities is high in the case of all pairs. But, the correlation between transitory volatilities turns out low. The reason is as follows. When economic information arrives, Seoul, Daejeon, and Busan housing markets, all together, are affected by this information.

• Information Systems Review
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• v.22 no.1
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• pp.167-182
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• 2020

Ambidexterity in organizations, in general, is interpreted as flexibility that enables organizational innovation, which is important for survival in a competitive market. It applies to individual workers as well since the ambidexterity of explorational and exploitational IS use will enable the flexible transition between dynamic and operational work, and hence, increase the work performance. The current study will therefore investigate the individual levels of exploratory and exploitative IS use, as well as the complementary relationship between exploratory and exploitative IS use. In a third step, the differential influence of IS on work performance will be evaluated. The current study validated that complementary fit of IS use exploration and IS use exploitation increases performance. Polynomial regression and surface analysis are used to validate the incongruence of IS use pattern. They showed that the incongruence of ambidexterity is composed of two types of divergent vs. convergent ambidexterity which depends on the type of work that need dynamic or operational capability.

• Journal of Digital Convergence
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• v.9 no.5
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• pp.235-251
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• 2011

Despite the increasing importance of information technology in firms, the extent to which IT governance are established varies widely across the firms. To perform desirably the role of IS needed in most companies, high level of IT governance and the effective management should precede. However, the impacts of such activities and management on the IT governance have not been empirically examined in depth until now. Thus, building on the theory of governance and the institutionalization, the research model and the hypotheses of the study were formed and then empirically tested. The study used a survey of senior IT managers from 108 firms in order to examine hypothesized relationship among the following constructs: strategic alignment, IT governance committee, IT planning, EA, PMO, SLM, IT compliance, incident management, IS effectiveness, visibility, and corporate performance. A structural equation model is developed by using LISREL to assess the relative effects and interrelationship among these constructs. The results show that strategic alignment has positive influence on IT governance committee and IT planning. IT governance committee, IT planning, SLM, incident management from IT governance activities have positive effects on IS effectiveness, whereas IT compliance has a negative effect on IS effectiveness. Visibility is positively influenced by IT planning, EA, SLM. IT compliance, and both IS effectiveness and visibility have positive effects on corporate performance.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.49 no.6
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• pp.449-456
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• 2021

In this paper, we present a strategy to extend solution capability of an existing low Mach number preconditioned compressible solver to incompressible flows with a little modification. To this end, the energy equation that is of the same form of the total energy equation of compressible flows is used. The energy equation is obtained by a linear combination of the thermal energy equation, the continuity equation and the mechanical energy equation. Subsequently, a modified artificial compressibility method in conjunction with a time marching technique is applied to these incompressible governing equations for steady flow solutions. It is found that the Roe average of the common governing equations is equally valid for both the compressible and incompressible flow conditions. The extension of an existing compressible solver to incompressible flows does not affect the original compressible flow analysis. Validity for incompressible flow analysis of the extended solver is examined for various inviscid, laminar and turbulent flows.

• Journal of Gifted/Talented Education
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• v.18 no.3
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• pp.465-496
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• 2008

With leadership and speciality, creativity is cutting a fine figure among major values of human resource in 21C knowledge-based society. In the 7th school curriculum much emphasis is put on the importance of creativity by pursuing the image of human being based on creativity based on basic capabilities'. Also creativity is one of major factors of giftedness, and developing one's creativity is the core of the program for gifted education. Doing mathematics requires high order thinking and knowledgeable understandings. Thus mathematical creativity is used as a measure to test one's flexibility, and therefore it is the basic tool for creativity study. But theoretical study for mathematical creativity is not common. In this paper, we discuss mathematical creativity applied to 6 approaches suggested by Sternberg and Lubart in educational theory. That is, mystical approaches, pragmatical approaches, psycho-dynamic approaches, cognitive approaches, psychometric approaches and scio-personal approaches. This study expects to give useful tips for understanding mathematical creativity and understanding recent research results by reviewing various aspects of mathematical creativity.

• International Area Studies Review
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• v.15 no.1
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• pp.425-446
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• 2011

There has been a conventional wisdom that a higher level of autonomy of a foreign subsidiary could lead to a higher level of subsidiary performance. Most MNCs seeking for managing localization efficiently followed this wisdom. But there has been no empirical evidence so far in academic journal that there is a clear positive relationship between subsidiary autonomy and performance. Recently most MNCs are trying to pursue a global strategy for managing foreign sudsidiaries, in which the coordination role of parent company is essential. For the MNCs seeking global strategy the coordination role of the parent and subsidiary autonomy appears to have a trade off relationship. It is uncertain in the situation that the positive relationship between subsidiary autonomy and performance is still effective. Therefore the purpose of the study is to provide an empirical evidence of the the hypothesis that there is a positive relationship between subsidiary autonomy and performance, The study utilized the questionaire survey of Korean subsidiaries of MNCs. The empirical results of the study showed the significant positive relationship between two variables, which is cinsistent to the hypotheses.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.14 no.2
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• pp.119-134
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• 2019

In order to accomplish a successful management consulting project, the client's receptivity to consulting as well as the management consultant's competency is very important. Even if a consultant with a high level of competence is put into a project, if the consulting receptivity of the company is low, a successful project can not be accomplished. On the other hand, even if consulting receptivity of the company is high, management consulting performance can not be expected if management consultant competency is lacking. This study analyzes the affect of consultant competency on management performance of client firms and the mediating effect of consulting receptivity of client company in terms of management performance. Management consultant competency is measured by task-related competency, managerial competency and common competency, and management performance is measured by financial performance and non-financial performance. The parameters are measured by consulting receptivity and management consulting performance. According to the results of the study, the management consultant's competency has a positive (+) influence on both of consulting receptivity and management consulting performance. Consulting receptivity has a positive (+) influence on both of management consulting performance and non-financial performance. Management consulting performance has a positive (+) influence on both of financial performance and non-financial performance. The mediating effect is that the consulting receptivity mediates directly or indirectly between management consultant competency and financial performance via management consulting performance and non-financial performance. The results of the empirical analysis of this study can contribute to the enhancement of management performance through management consulting in viewpoints of client firms and also contributing to more efficient and effective management consulting.

• Management & Information Systems Review
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• v.30 no.2
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• pp.237-255
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• 2011

This empirical study is focused on practical application of Range-Based Volatility which is estimated by opening, high, low, closing price of overall asset. Especially proper forecasting period is what I want to know. There is four useful Range-Based Volatility(RV) such as Parkinson(1980; PK), Garman and Klass(1980; GK) Rogers and Satchell(1991; RS), Yang and Zhang(2008; YZ). So, four RV of KOPSI 200 index during 2000.5.22-2009.9.18 was used for empirical test. The emprirical result as follows. First, the best RV which shows the best forecasting performance is PK volatility among PK, GK, RS, YZ volatility. According to estimating period forcasting performance of RV shows delicate difference. PK has better performance in the period with financial crisis of sub-prime mortgage loan. if not, RS is better. Second, almost result shows better performance on forecasting volatility without sub-prime mortgage loan period. so we can say that forecasting performance is lower when historical volatiltiy is comparatively high. Finally, I find that longer estimating period in AR(1) and MA(1) model can reduce forecasting error. More interesting point is that the result shows rapid decrease form 60 days to 90 days and there is no more after 90 days. So, if we forecast the volatility using Range-Based volaility it is better to estimate with 90 trading period or over 90 days.

• Journal of Digital Convergence
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• v.9 no.2
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• pp.111-129
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• 2011

Nowadays, the IS project is getting more and more complicated and large-scaled. Many researchers and practitioners are interested in the IS development methodologies, automated tools and techniques to decrease project failure and to increase IS project performance. This research is to seize the management level of PMO affecting on the IS project, as a new method to increase the IS project development performance. As a result of surveying the present PMO operation state with banks which are the leading industry to accept the PMO in Korea, technology support management and infrastructure management are the core functions to affect the IS performance including schedule management, quality management, and user and stakeholders' satisfaction. Also, the PMO management level is the important point of IS project success. Among the 5 levels PMI suggested, PMO can implement the project effectively at least at the third level. Korean companies introducing the PMO have to do research the PMO core functions and the management levels according to the project scale, and review the distinctive features of their organization to increase the maturity of IS project. This research has been proved through the Full Structural Equation Model. The results show that the five core functions of PMO have relationship with the IS project performance.

• Management & Information Systems Review
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• v.31 no.1
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• pp.45-63
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• 2012

The purpose of this study is to investigated the association between the percentage of common stock held by a company's CEO and measure firm performance in down and up markets. We found that managerial ownership is associated positively with firm performance. We also found that although firms with high insider ownership generally outperform other firms, this relationship is diminished in down markets and is increased in up market. These results suggest that investment strategies based on the assumption that high insider ownership is associated positively with financial performance may be faulty in declining market.