• The Journal of Korean Institute of Communications and Information Sciences
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• v.38A no.6
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• pp.492-503
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• 2013

H.264/AVC has shown high coding efficiency by using various coding tools, including intra and inter prediction. However, there are still many more redundancy components in intra prediction than in inter prediction. In this paper, a novel intra prediction method is proposed with adaptive mode selection. The combined intra prediction modes and simplified gradient modes are added in order to refine the directional feature and gradation region. Suitable modes are selected according to the neighboring blocks that provide a high compression rate and lower computational complexity. The improvement of the proposed method is 1.96% in terms of the bitrate, 0.25 dB in PSNR, and 1.72 times in terms of the computational complexity.

• Structural Engineering and Mechanics
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• v.5 no.3
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• pp.269-281
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• 1997

The overall buckling mode in a composite steel-concrete beam over an internal support is necessarily lateral-distortional, in which the bottom compressive range displaces laterally and twists, since the top flange is restrained by the nearly rigid concrete slab. An efficient finite element method is used to study elastic lateral-distortional buckling in composite beams whose steel portion is tapered. The simplified model for a continuous beam that is presented herein is a fixed ended cantilever whose steel portion is tapered, and is subjected to moment gradient. This is intended to give an insight into distortion in a continuous beam that occurs in the negative bending region, and the differences between the cantilever representation and the continuous beam are highlighted. An eigenproblem is established, and the buckling modes and loads are determined in the elastic range of structural response. It is found from the finite element study that the buckling moment may be enhanced significantly by using a vertical stiffener in the region where the lateral movement of the bottom range is greatest. This enhancement is quantified in the paper.