• The Journal of Information Technology and Database
• /
• v.8 no.2
• /
• pp.137-159
• /
• 2001

This study provides a thorough methodology for IT Investment evaluation. A software tool to support the evaluation process was introduced along with a case study. The software supports the methodology that consists of 7 phases : Target analysis, ldentifying IT measures, Measuring IT impact, Assessing business value, Analyzing the decree of realization, Cost-benefit analysis, and Reporting. The case study showed that the software (CAFA) was a very useful tool supporting both decision-making and post-implementation reviews of IT investment.

• Proceedings of the KIPE Conference
• /
• 1999.07a
• /
• pp.256-259
• /
• 1999

A new PWM method for voltage source inverters is described. The switching instants determination of the proposed PWM scheme is simple. Therefore, hardware implementation with a microprocessor system is easy and high frequency operation of an inverter can be obtained. The maximum line-to-line output voltage of 3-phase inverter with the proposed scheme is larger than that of the SPWM inverter under a linear modulation region. Principle of the proposed PWM method is described and harmonic characteristic analysis is carried out.

• Proceedings of the IEEK Conference
• /
• 2008.06a
• /
• pp.751-752
• /
• 2008

This paper introduces current technology trend of cell planning system in radio propagation and 3D GIS technologies which are implemented in Cell planning system "CellTREK" for accurate radio propagation analysis. It includes managing of DTM(Digital Terrain Model) data considering building height used by 3D propagation analysis module, and navigation module based on DirectX technology to estimate and eliminate the shadowing area by high rise buildings.

• Proceedings of the IEEK Conference
• /
• 2002.06b
• /
• pp.277-280
• /
• 2002

This paper analyze the characteristics of three multipliers in finite fields GF(2m) from the point of view of processing time and area complexity. First, we analyze structure of three multipliers; 1) LSB-first systolic array, 2) LFSR structure, and 3) CA structure. To make performance analysis, each multiplier was modeled in VHDL and was synthesized for FPGA implementation. The simulation results show that LFSR structure is best from the point of view of area complexity, and LSB systolic array is best from the point of view of processing time per clock.

• Proceedings of the Computational Structural Engineering Institute Conference
• /
• 2003.04a
• /
• pp.145-152
• /
• 2003

This paper develops a relatively comprehensive and sophisticated constitutive model of concrete for finite element analysis of concrete structures. The present model accounts for the hydrostatic pressure sensitivity and Lode angle dependence behavior of concrete, not only in its strength criterion, but also in its hardening characteristics. The implementation is carried out through incorporating the developed concrete model in User Subroutine Material(UMAT) of the general-purpose FE program ABAQUS(v.5.8). It is found that the model can sufficiently predict the hardening as well as the softening behaviour of concrete under high confining pressure.

• Proceedings of the KWS Conference
• /
• 2004.05a
• /
• pp.273-275
• /
• 2004

A parallel multi-frontal solver is developed for finite element analysis of an arc-welding process, which entails phase evolution, heat transfer, and deformations of structure. We verify the code via comparison to a commercial code,SYSWELD. Attention is focused on the implementation of the parallel solver using MPI library, on the speedup by parallel computation, and on the effectiveness of the solver in welding application

• Proceedings of the Korea Concrete Institute Conference
• /
• 2003.05a
• /
• pp.409-414
• /
• 2003

This paper develops a relatively comprehensive and sophisticated constitutive model of concrete for finite element analysis of concrete structures. The present model accounts for the hydrostatic pressure sensitivity and Lode angle dependence behavior of concrete, not only in its strength criterion, but also in its hardening characteristics. The implementation is carried out through incorporating the developed concrete model in User Subroutine Material(UMAT) of the general-purpose FE program ABAQUS(v.5.8). It is found that the model can sufficiently predict the hardening as well as the softening behaviour of concrete under high confining pressure.

• Proceedings of the KIEE Conference
• /
• 2008.07a
• /
• pp.211-212
• /
• 2008

As a result of environmental concerns, the production of electricity through renewable energy resources is rapidly increasing. Wind energy is among the fastest growing renewable energy resources now being integrated in the power system, and the penetration rate of wind generation has been gradually increased. For power flow analysis of the recent systems, thus, steady-state modeling of wind turbines and their application are of great importance. This paper presents the procedure we applied for implementation of a steady-state wind turbine model in power flow.

• Proceedings of the KIEE Conference
• /
• 2008.10c
• /
• pp.145-147
• /
• 2008

In this paper, the implementation of the Permanent Magnet Synchronous Machine (PMSM) model based on the Matlab/Simulink is described. Due to the analysis of the mathematical dq-modeling, a vector controlled PMSM drive simulation is approached. With the simulated system, unlike in black block models, all machine parameters are accessible for control and verification. Based on the Matlab/Simulink, the model of the PMSM with load torque is established, the simulation is studied and some conclusions are given.

• Journal of Korean Society for Quality Management
• /
• v.26 no.2
• /
• pp.17-26
• /
• 1998

Taguchi's parameter design is a method for quality improvement by making the performance fo a system robust to noise. Parameter design with dynamic characteristics has been recently the subject of much interest. This paper is concerned with a review and a generalization of the Signal-to-Noise (SN) ratio, a quality measure for parameter design with dynamic characteristics, proposed by Taguchi. We present a method for determination and analysis of the generalized SN ratio and illustrate its implementation by example.