• KSII Transactions on Internet and Information Systems (TIIS)
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• v.10 no.7
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• pp.2992-3009
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• 2016

The performance of D-MIMO systems is not only affected by multipath fading but also from shadowing fading, as well as path loss. In this paper, we investigate the ergodic capacity of D-MIMO systems operating in non-correlated K fading (Rayleigh/Gamma) channels. With the aid of majorization and Minkowski theory, we derive analytical closed-form expressions of the upper and lower bounds on the ergodic capacity for D-MIMO systems over non-correlated K fading channels, which are quite general and applicable for arbitrary signal-to-noise ratio (SNR) and the number of transceiver antennas. To intuitively reveal the impacts of system and fading parameters on the ergodic capacity, we deduce asymptotic approximations in the high and low SNR regimes. Finally, we pursue the massive MIMO systems analysis for the lower bound and derive closed-form expressions when the number of antennas at BS grows large, and when the number of antennas at transceivers becomes large with a fixed and finite ratio. It is demonstrated that the proposed expressions on the ergodic capacity accurately match with the theoretical analysis.

• Proceedings of the Korean Institute of Intelligent Systems Conference
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• 2007.11a
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• pp.15-18
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• 2007

Identification of humans from multiple view points is an important task for surveillance and security purposes. For optimal performance the system should use the maximum information available from sensors. Multimodal biometric systems are capable of utilizing more than one physiological or behavioral characteristic for enrollment, verification, or identification. Since gait alone is not yet established as a very distinctive feature, this paper presents an approach to fuse face and gait for identification. In this paper we will use the single camera case i.e. both the face and gait recognition is done using the same set of images captured by a single camera. The aim of this paper is to improve the performance of the system by utilizing the maximum amount of information available in the images. Fusion is considered at decision level. The proposed algorithm is tested on the NLPR database.

• The Journal of Information Systems
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• v.19 no.1
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• pp.97-116
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• 2010

Failures of super large projects like IT Upgrade of Shinhan Financial Group can be a heavy blow not only to the company but even to the national economy. Research on the practices of risk management in those projects will provide invaluable lessons, enhancing capabilities and chances of successfully executing mission critical projects of the companies and the national economy as a whole. This paper analyzes the risk management of the Core Systems Reconstruction which was the most critical component of IT Upgrade. The analysis covers risk management plans, and identification and evolution, and control and monitoring of risk factors. This study confirms the major results of previous research on risk management in Korea. However, the analysis found as well some discrepancies of practices from the previous research results. This research also tracked the trajectories of evolution of risk factors and management. In particular, in depth analysis of control and monitoring is the first research in Korea on the "management" of risks in IT projects. The result of this research is expected to be a useful guide for theory development and practices of risk management in the future.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.31 no.1
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• pp.1-10
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• 2008

The enormous budget of government and manpower are invested to the government funded institutes every year. The R&D investment focused on input has to be turned toward the investment based on the effectiveness of R&D activities. Measuring the efficiency of research activities is required in order to evaluate the effectiveness of R&D investment in these institutes. The purpose of this paper is to evaluate the relative efficiency of research activities performed in 19 government funded research institutes. CCR/BCC model and DEA/AR model were applied to get the relative efficiency of 19 institutes. Assurance regions for the weight of output attributes were obtained by using the underlined concept of the analytic hierarchy process (AHP). We used input and output data items describing research activity of 19 government funded research institutes. The results of this study are expected to become a basis of the R&D investment decision of the government.

• The Journal of Information Systems
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• v.26 no.1
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• pp.53-73
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• 2017

Frequent outbreak of intrusion of private information is occurring recently not only at portal sites but also in electronic information service of public agencies. Due to these intrusions, it is observed that the citizens tend to avoid providing their private information even to the service for public agencies. Therefore, the object of this research can be explained as demonstrating the influence of the intention of provision for private information to foster the selectronic information ervice of the public agencies. In order to achieve this, this research intends to demonstrate how the experience of the intrusion of the private information affects the concern about the privacy and how the information factor from the public electronic information service has influence on the reliability toward the public. The results showed that the experience of intrusion of privacy, awareness of the danger of privacy, and the sense protection of the information from the manager at public agencies have direct influence on the concern of privacy. Meanwhile, it has been verified that the awareness of information protection of a manager, the systemicity of information protection, and the surveillance and punishment of information protection have influence on the reliability of public agencies.

• Journal of Korea Society of Industrial Information Systems
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• v.17 no.3
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• pp.69-81
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• 2012

In this paper we analyze ERP systems performance by ERP system factors in two Korea firms and two China firms and propose strategies for successful ERP systems construction. To achieve these goals we conduct a literature review in ERP success factors and implementation strategy and then conduct an empirical analysis focus on three ERP system factors, Ease of Use, Flexibility, and Utilizability of ERP systems, and comparability analysis between Korea and China firms by ERP system factors. Based on these results, we present practical guidelines to construct ERP systems successfully by three ERP system factors in this research.

• ETRI Journal
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• v.42 no.3
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• pp.351-365
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• 2020

Directional sensor networks (DSNs) can significantly improve the performance of a network by employing energy efficient communication protocols. Neighbor discovery is a vital part of medium access control (MAC) and routing protocol, which influences the establishment of communication between neighboring nodes. Neighbor discovery is a challenging task in DSNs due to the limited coverage provided by directional antennas. Furthermore, in these networks, communication can only take place when the beams of the directional antennas are pointed toward each other. In this article, we propose a novel multiple token-based neighbor discovery (MuND) protocol, in which multiple tokens are transmitted based on an area exploration algorithm. The performance of the protocol is evaluated using the Cooja simulator. The simulation results reveal that the proposed MuND protocol achieves lower neighbor discovery latency, with a 100% neighbor discovery ratio, and has a relatively low communication overhead and low energy consumption.

• Asia pacific journal of information systems
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• v.12 no.2
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• pp.137-162
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• 2002

As the ERP system become recognized as a strategic weapon of a firm, the way how to implement the system successfully has been an important issue for both practitioners and the academic community. The objective of this research is to identify the critical success factors influencing the implementation of the ERP system and to suggest the tasks to be considered first for the effective implementation of the system. The results from the analysis of data collected from the 169 firms among those which have implemented either the Oracle package or the SAP package in Korea are as follows. The important factors for the successful implementation of the ERP system include the strength of rivalry among competing firms; the degree to which information systems are matured; the information systems strategy of a firm; the support and concern from the top; and the technical openness between the ERP system and the legacy system such as network, hardware, and software. The tasks to be considered first for the effective implementation of the ERP system cover the same degree of feeling between labor and management on the threat to survive; the formulation of information systems strategy at the strategic level; CEO's strong will and resolution; the process automation and informatization of a firm; and the infrastructure including intranet and databases.

• Information Systems Review
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• v.4 no.2
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• pp.273-291
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• 2002

For many organization, a strategic information systems planning (SISP) continues to be a critical issue. This paper is an empirical study of what is being done in Korea with respect to SISP. A survey questionnaire was mailed to the major 1000 Korean companies. In this research, the experiences of 51 companies contribute the SISP practices including the success factor of SISP. Forty-three percent of the respondents indicated that their companies undertook some form of SISP. We also compared finding with the state of SISP practices in Singapore.

• International Journal of Computer Science & Network Security
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• v.23 no.7
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• pp.101-108
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• 2023

Decision Support Systems (DSS) is an Information Systems (IS) application that aids in decision-making processes for many business concepts and Customer Relationship Management (CRM) is one of them and it depends on the firm's tasks for developing and retaining customers while achieving their satisfaction and enhancing the sense of belongingness for their products and services. Profit maximization, the process of customer value, and building strategic values for the firm are the three empirical benefits of CRM that are achieved through analytical, operational, and direction (AOD) capabilities respectively. This research focuses on the application of DSS models of what-if analysis (WIA) for CRM at (AOD) and also shows the dependence on the Information Success model (ISM). Hypothetical data are analyzed for (AOD) by three types of (WIA) to attain CRM and profit maximization and this analytical method can be used by any customer-oriented firm as a general model and for the purpose of the study we have compared the CRM between patients and hospital management.