• Proceedings of the IEEK Conference
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• 2002.07c
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• pp.1839-1842
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• 2002

Ad hoc networks are characterized by multi- hop wireless connectivity, frequently changing network topology and the need for efficient dynamic routing protocols. In this paper, we proposed a new technique to adjust the zone radius by concentrating the changes of network traffic in a particular direction, which we refer to as AZRP. We demonstrate that even though ZRP and AZRP share a similar hybrid routing behavior, the differences in the protocol mechanics can lead to significant performance differentials. We discuss the algorithm and report on the performance of AZRP scheme, and compare it to the ZRP routing protocol. Our results indicate clearly that AZRP outperforms ZRP by reducing significantly the number of route query messages. And thereby increases the efficiency of the network load.

• Journal of Advanced Marine Engineering and Technology
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• v.32 no.4
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• pp.528-533
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• 2008

A closed circuit cooling tower having high temperature of cooling water and small water flow rate is investigated. To study the characteristics of the heat transfer of heat exchanges in a cooling tower with multi paths a numerical method is used. The results show that the staggered tube arrangements in a bank show better performance than aligned ones for temperature variation with various outer diameters of tube bundles. In case of one pass, the 15.88 mm tube case shows about 9% better performance than the 25.4 mm tube case. In two paths, the tube outside diameter of 15.88 mm show about 14.4% better results than the 25.4 mm diameter case.

• Journal of Information Technology Applications and Management
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• v.13 no.4
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• pp.273-290
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• 2006

This study suggests a frequency matrix technique to predict personal credit rate more efficiently using incomplete data sets. At first this study test on multiple discriminant analysis and logistic regression analysis for predicting personal credit rate with incomplete data sets. Missing values are predicted with mean imputation method and regression imputation method here. An artificial neural network and frequency matrix technique are also tested on their performance in predicting personal credit rating. A data set of 8,234 customers in 2004 on personal credit information of Bank A are collected for the test. The performance of frequency matrix technique is compared with that of other methods. The results from the experiments show that the performance of frequency matrix technique is superior to that of all other models such as MDA-mean, Logit-mean, MDA-regression, Logit-regression, and artificial neural networks.

• 한국IT서비스학회:학술대회논문집
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• 2007.11a
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• pp.573-576
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• 2007

최근 정보시스템 개발 프로젝트의 복잡성과 규모의 증대로 인해 프로젝트를 체계적이고 전문적으로 관리할 수 있도록 PMO의 도입이 증가하고 있다. 하지만 PMO의 도입은 늘어가는데, 프로젝트 특정에 따른 PMO가 제공해야 할 서비스에 대한 체계적인 연구나 방향 제시가 부족한 실정이다. 또한 PMO 기능 또는 PMO서비스 수준이 프로젝트 성과나 사용자 만족도에 미치는 영향에 대한 연구도 부족하다. 따라서 본 논문에서는 프로젝트 특성에 따른 PMO 서비스 수준이 프로젝트 성과에 미치는 영향을 연구하고자 한다.

• Journal of the Korean Operations Research and Management Science Society
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• v.16 no.2
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• pp.51-51
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• 1991

Recently financial institutions in Korea are experiencing an unfamiliar challenge in terms of their operational risk management due to the volatility of global financial market and the incessant development of new financial products. In this paper, we present an AHP(Analytic Hierarchy Process) model to evaluate the effectiveness of commercial softwares for risk management in banking. The AHP model considers software's performance. utility, serviceability and durability as major evaluation criteria. The weight of each criterion is generated by the questionnaire survey given to practitioners in risk management in domestic commercial banks.

• Proceedings of the IEEK Conference
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• 2002.07b
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• pp.912-915
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• 2002

In this report, we propose a non-separable two-dimensional (2D) Lossless Wavelet Transform (LWT) for image compression. Filter characteristics of our proposed LWT are the same as those or conventional 2D LWT based on applying 1D LWT twice but our coding performance is better due to reduction of rounding effects. Simulation results confirm effectiveness of our proposed LWT.

• Korean Management Science Review
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• v.16 no.2
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• pp.51-59
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• 1999

Recently financial institutions in Korea are experiencing an unfamiliar challenge in terms of their operational risk management due to the volatility of global financial market and the incessant development of new financial products. In this paper, we present an AHP(Analytic Hierarchy Process) model to evaluate the effectiveness of commercial softwares for risk management in banking. The AHP model considers software's performance. utility, serviceability and durability as major evaluation criteria. The weight of each criterion is generated by the questionnaire survey given to practitioners in risk management in domestic commercial banks.

• Proceedings of the Korea Institute of Convergence Signal Processing
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• 2001.06a
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• pp.25-28
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• 2001

A new decision-feedback equalization technique for a filter bank-based orthogonal frequency division multiplexing (OFDM) data transmission system operating in a frequency selective multipath fading channel is presented in this paper. At the cost of relatively increased computational complexity in comparison to the conventional OFDM systems, the proposed system achieves a better performance in terms of bit error rates. The simulation results confirm the superiority and robustness of our method, particularly, in the low SNR channel environment.

• Journal of Mechanical Science and Technology
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• v.20 no.10
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• pp.1557-1566
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• 2006

We present a procedure for the application of global orthogonal polynomial into an atmospheric re-entry maneuvering problem. This trajectory optimization is imbedded in a family of canonically parameterized optimal control problem. The optimal control problem is transcribed to nonlinear programming via global orthogonal polynomial and is solved a sparse nonlinear optimization algorithm. We analyze the optimal trajectories with respect to the performance of re-entry maneuver.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.18 no.35
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• pp.165-175
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• 1995

The objective of this study is to evaluate the reliability of DEA for the measurement of efficiency of Commercial banks in Korea using the DEA methods. DEA is basically a mathematical programing technique initially developed by Chanes, Cooper and Rhodes(197n) to evaluate the relative efficiency of not-for-profit organizations where multiple outputs are produced with multiple inputs. This study show that DEA approach is not only usefulness in evaluating performance of banks but also a useful bank management tool.