• International Journal of Contents
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• v.1 no.2
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• pp.35-38
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• 2005

This paper describes a design of simple and precision direction finder that can be adapted to shipboard or mobile vehicles used for Electronic support measure, ELINT and radio signal monitoring systems. The direction finding technology has improved with monolithic integrated circuit, linear array antennas, and interferometer. Interferometer uses the phase-comparison principle and has a good direction finding accuracy but it has an ambiguity problem. We suggest a simple ambiguity solver using phase-comparison technology with amplitude-comparison principle. The direction finding device that has been designed by the suggested method has 0.7 degree RMS error in azimuth angle and 0.6 degree RMS error in elevation angle in 0.5 - 2.0 GHz.

• Structural Engineering and Mechanics
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• v.32 no.6
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• pp.705-724
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• 2009

The two major widely used building design code documents of reinforced concrete structures are the ACI 318-05 and Eurocode for the Design of Concrete Structures EC2. Therefore, a thorough comparative analysis of the provisions of these codes is required to confirm their validity and identify discrepancies in either code. In this context, provisions of flexural computations would be particularly attractive for detailed comparison. The provisions of safety concepts, design assumptions, cross-sectional moment capacity, ductility, minimum and maximum reinforcement ratios, and load safety factors of both the ACI 318-05 and EC2 is conducted with parametric analysis. In order to conduct the comparison successfully, the parameters and procedures of EC2 were reformatted and defined in terms of those of ACI 318-05. This paper concluded that although the adopted rationale and methodology of computing the design strength is significantly different between the two codes, the overall EC2 flexural provisions are slightly more conservative with a little of practical difference than those of ACI 318-05. In addition, for the limit of maximum reinforcement ratio, EC2 assures higher sectional ductility than ACI 318-05. Overall, EC2 provisions provide a higher safety factor than those of ACI 318-05 for low values of Live/Dead load ratios. As the ratio increases the difference between the two codes decreases and becomes almost negligible for ratios higher than 4.

• Proceedings of the Korea Society of Design Studies Conference
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• 2002.05b
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• pp.116-117
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• 2002

• Proceedings of the Korea Society of Design Studies Conference
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• 1998.10a
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• pp.12-13
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• 1998

• Proceedings of the Korea Society of Design Studies Conference
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• 2001.10a
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• pp.45-45
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• 2001

• Journal of Electrical Engineering and Technology
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• v.6 no.2
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• pp.182-191
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• 2011

Genetic algorithms (GA) and particle swarm optimization (PSO) are the most famous optimization techniques among various modern heuristic optimization techniques. These two approaches identify the solution to a given objective function, but they employ different strategies and computational effort; therefore, a comparison of their performance is needed. This paper presents the application and performance comparison of the PSO and GA optimization techniques for a static synchronous series compensator-based controller design. The design objective is to enhance power system stability. The design problem of the FACTS-based controller is formulated as an optimization problem, and both PSO and GA optimization techniques are employed to search for the optimal controller parameters.

• Proceedings of the Korea Society of Design Studies Conference
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• 2005.05a
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• pp.306-307
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• 2005

• Earthquakes and Structures
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• v.18 no.1
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• pp.27-44
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• 2020

This work presents a comparison of three performance-based seismic design methods (PBSD) as applied to plane steel frames having eccentric braces (EBFs) and buckling restrained braces (BRBFs). The first method uses equivalent modal damping ratios (ξ_k), referring to an equivalent multi-degree-of-freedom (MDOF) linear system, which retains the mass, the elastic stiffness and responds in the same way as the original non-linear MDOF system. The second method employs modal strength reduction factors (${\bar{q}}_k$) resulting from the corresponding modal damping ratios. Contrary to the behavior factors of code based design methods, both ξ_k and ${\bar{q}}_k$ account for the first few modes of significance and incorporate target deformation metrics like inter-storey drift ratio (IDR) and local ductility as well as structural characteristics like structural natural period, and soil types. Explicit empirical expressions of ξ_k and ${\bar{q}}_k$, recently presented by the present authors elsewhere, are also provided here for reasons of completeness and easy reference. The third method, developed here by the authors, is based on a hybrid force/displacement (HFD) seismic design scheme, since it combines the force-base design (FBD) method with the displacement-based design (DBD) method. According to this method, seismic design is accomplished by using a behavior factor (q_h), empirically expressed in terms of the global ductility of the frame, which takes into account both non-structural and structural deformation metrics. These expressions for q_h are obtained through extensive parametric studies involving non-linear dynamic analysis (NLDA) of 98 frames, subjected to 100 far-fault ground motions that correspond to four soil types of Eurocode 8. Furthermore, these factors can be used in conjunction with an elastic acceleration design spectrum for seismic design purposes. Finally, a comparison among the above three seismic design methods and the Eurocode 8 method is conducted with the aid of non-linear dynamic analyses via representative numerical examples, involving plane steel EBFs and BRBFs.

• The Journal of Information Systems
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• v.32 no.4
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• pp.163-188
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• 2023

Purpose The study examines the impact of the level of anthropomorphism (both in appearance and behavior) of virtual humans on user liking. It investigates whether this relationship is mediated by social comparison experiences, with the moderated mediation effect of users' desire for self-improvement. Design/methodology/approach A between-groups experimental design was employed to examine the impact of different levels of appearance(low/mid/high) and behavior(low/high) anthropomorphism on user liking of virtual humans. The experiment was conducted in an online environment, and participants were randomly exposed to one of six stimuli, which were Instagram-like posts. Findings The results indicate that as virtual humans become more anthropomorphic, they have a positive impact on user liking. However, once the level of anthropomorphism in appearance reaches a certain point (mid vs high), there is no significant difference in user liking. Users who perceive virtual humans as highly anthropomorphic tend to engage in more social comparison experiences, which positively affects their liking for these virtual humans. Conversely, individuals with a high desire for self-improvement found that the positive effect of appearance anthropomorphism on liking through social comparison experiences was reduced. The study extends the application of social comparison theory by examining its impact on influencer marketing with virtual beings. It provides valuable insights for the formulation of influencer marketing strategies using virtual humans.

• Proceedings of the Korea Society of Design Studies Conference
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• 2002.11b
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• pp.68-69
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• 2002