• Asia pacific journal of information systems
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• v.12 no.1
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• pp.45-65
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• 2002

Factors influencing the success or failure of information systems(IS) have been discussed in many literature. However, limited theoretical development or empirical research have examined the effectiveness of hospital information systems(HIS). This study set out the research model of influencing factors and the performance of HIS through theoretical studies based on Management Information Systems, and then empirically tested hypotheses related to the model. The model was tested using LISREL analysis on the sample of 274 respondents who have worked with the HIS. The major results of this study are as follows: First, system characteristics and organizational characteristics have a statistically significant influence on user satisfaction. Second, the hypothesis 3, proposing that computer self-efficacy would relate positively to user satisfaction, was not supported by the results, though. According to these results, system quality, information quality, service quality and support of top management are very important variables for IS success. The study's findings also indicate DeLone and McLean's model is correct in proposing that the indirect relationship between influencing factors and organizational effectiveness, mediated by user satisfaction, is an important one.

• Journal of Communications and Networks
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• v.12 no.6
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• pp.605-615
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• 2010

Intercarrier interference (ICI) in orthogonal frequency division multiplexing (OFDM) systems, which causes substantial performance degradation in time-varying fading channels, is analyzed. An equivalent spreading code formulation is derived based on the analogy of OFDM and code division multiple access (CDMA) systems. Techniques as linear multiuser detection in CDMA systems are applied to suppress the ICI in OFDM systems. The performance of linear detection, measured using multiuser efficiency and asymptotic multiuser efficiency, is analyzed given the assumption of perfect channel state information (CSI), which serves as an upper bound for the performance of practical systems. For systems without CSI, time domain and frequency domain channel estimation based linear detectors are proposed. The performance gains and robustness of a linear minimum mean square error (LMMSE) filter over a traditional filter (TF) and matched filter (MF) in the high signal-to-noise ratio (SNR) regime are demonstrated with numerical simulation results.

• The Journal of Information Systems
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• v.25 no.1
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• pp.49-73
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• 2016

Purpose Though many information systems researchers have made various attempts to investigate the relationship between information technology capability and firm performance from diverse perspectives, we have not come to a conclusion yet with some mixed results. In this research, focusing on the adoption of Enterprise Resource Planning (ERP) systems by firms as a proxy measure for information technology capability, we reexamine whether the association is significantly positive. Design/methodology/approach Previous research on this topic had some limitations to the samples and analysis method. Some research focused only on the 1990s or early 2000s, and other studies failed to adequately compare the impact of ERP adoption on firm performance between the treatment group and the control group. In this research, extending previous analysis approaches with the matched sample comparison of IT leaders and the control group, we attempt to apply propensity score matching in combination with difference-in-difference analysis with a sample of Korean firms that adopted ERP systems in the late 2000s. We match ERP adopters and non-adopters with propensity score matching and compare their financial performance with difference-in-difference estimation between the pre- and post-adoption periods. Findings According to our analysis, we find no positive and significant relationship between ERP adoption and firm performance in profit ratios. This research shows that, contrary to the era of proprietary information systems, standardized information systems today have no additional competitive advantages over competitors.

• Journal of Korean Society for Quality Management
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• v.28 no.2
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• pp.89-102
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• 2000

Many organizations have developed their own traditional quality information systems. But, they think of it as one of the functional information systems not as a company-wide decision support information systems. A study on traditional quality information systems(QIS) has been conducted and a new conceptual framework of quality information system is proposed in this paper. In order to support enterprise wide total quality management aggressively, a new conceptual framework, named quality management support information system(QMSIS) is developed and proposed. This framework is based upon Malcolm Baldrige National Quality Award(MBNQA) model integrates management information system approach and traditional quality information system concept. In this model, organizational performance and process performance can be monitored to support managers , decision making about organizational quality management activities.

• The Journal of Information Systems
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• v.17 no.3
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• pp.1-24
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• 2008

This study empirically investigated the relationships among inter-organizational contextual factors(assets specificity, long-term orientation and interdependence), information exchange between trading partners, inter-organizational loaming and trust, and inter-organizational performance. In this study, types of information exchanged between trading firms are classified into two broad kinds: transaction information and management information. from empirical results, we found that inter-organizational contextual factors have a greater positive impact on the exchange of management information. It is also observed that the exchange of information positively influences inter-organizational trust and loaming. finally, the results of this study showed that inter-organizational trust and teaming have positive effects on the improvement of inter-organizational performance. Thus, it is concluded that the amount of information exchanged according to the conditions of inter-organizational contextual factors gives rise to inter-organizational teaming and high levels of trust, and high levels of trust and learning contribute to the increase of inter-organizational performance.

• The Journal of Information Systems
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• v.15 no.2
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• pp.95-123
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• 2006

It is needed to evaluate information systems actively which has already developed to improve future performance of the organization and foster the activation of information system. The introduction or development of information system also can bring about a organizational success. To measure exactly the organizational performance of information systems, it is needed to develop a new valuation model for a specific information system from a objective pint of view, as well as to equip a standard methodology using BSC measurement. The information system valuation from a objective point of view is of importance as the basic information for the decision to obtain information system. This paper takes aim at investigating a new information system valuation model and developing a information system valuation system using case-based reasoning for predicting currency value of information system in each organization. A new information system valuation system is developed as a web-enabling base. Using this, users are able to estimate the value of specific information system on a real time efficiently.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.32 no.2A
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• pp.162-168
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• 2007

This paper proposes two detection algorithms for Multi-user Space Time Block Code systems. The first one is linear detection Gaussian Elimination algorithm, and then it combined with Ordered Successive Cancellation to get better performance. The comparisons between receiver and other popular receivers, including linear receivers are provided. It will be shown that the performance of Gaussian Elimination receiver is similar but more simplicity than linear detection algorithms and performance of Gaussian Elimination Ordered Successive Cancellation superior as compared to other linear detection method.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.19 no.2
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• pp.293-300
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• 2015

Recently, multiuser diversity(MUD) technique is used to improve the performance of OFDM transmission systems. With STBC antenna diversity technique, the performance of OFDM systems can be also improved. Pilot symbol is used for the channel estimation in OFDM systems. However, imperfect channel estimates in this systems degrade the performance. The performance of MUD STBC OFDM systems using pilot symbol, gauged by the bit error rate, is analyzed considering the channel estimation error. Result shows that MUD can improve the required power by a factor of approximately 5 dB for users number 32.

• Knowledge Management Research
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• v.18 no.3
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• pp.231-246
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• 2017

As an interest in the efficiency of public sector expenditures has spread across the world, Korea has operated a self-evaluation system for government projects as a part of the performance-based budget system. However, an evaluation system for public information technology project has been criticized for its lack of validity, which stems from the uniformity of performance management. This study draws insight from knowledge management literature in an attempt to address the problems with the extant performance evaluation system in public agencies. To realize benefits from IT investment, an agency needs to develop its own performance management model for information systems projects, with a focus on the interaction of IT and organizational system. The knowledge management-based framework for IT projects was verified through a case study, with which we discussed the applicability of knowledge management to the evaluation of public information systems projects.

• Proceedings of the IEEK Conference
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• 2002.07b
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• pp.1066-1069
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• 2002

Orthogonal frequency division multiplexing (OFDM) is a special technique for communication systems which can support the high data rate transmission with sufficient robustness to fading channels. Tansmitter diversity with space-time block coding (STBC) is an attractive transmission scheme to improve the performance of systems. In this paper, we compare the performance of space-time block coded OFDM systems with that of conventional OFDM systems over fast fading channels. The block-interleaved (BI) STBC and frequency hopping (FH) OFDM are proposed in the study to provide the maximum achievable diversity gains. As the simulation results, the STBC OFDM, Bl-STBC OFDM and Bl-STBC FH-OFDM provide the much improved performance over the conventional OFDM. And the Bl-STBC FH-OFDM also provide the better performance than the STBC OFDM and Bl-STBC OFDM, especially, in the case of the two transmit antennas are employed while BI-STBC FH-OFDM can maintain the same data rate of 12 Mbps.