• Proceedings of the Computational Structural Engineering Institute Conference
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• 2002.10a
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• pp.33-38
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• 2002

Dynamic analysis of laminated beams with a embedded damping layer under tension or compression axial load is investigated. Layer-Wise Zig-Zag Beam Theory and Interdependent Kinematic Relation using the governing equations of motion are incorporated to model the laminated beams with a damping layer and a corresponding beam zig-zag finite element is developed. Flexural frequencies and modal loss factors under tension or compression axial load are calculated based on Complex Eigenvalue Method. The effects of the axial tension and compression load on the frequencies and loss factors are discussed.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 1995.03a
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• pp.107-113
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• 1995

To investigate the behavior of platic deformation inaxisymmetric hot extrusion through square dies, the physical modelling with the plasticine as a model material is carried out at the room temperature. Some mechanical properties of the model material are determined by compression and ring compression tests. Visioplasticity method using experimetal grid distortion is introduced to anlayze the plastic flow, strain rate and strain distribution.

• Proceedings of the KSME Conference
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• 2003.11a
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• pp.420-423
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• 2003

A low temperature difference model Stirling engine is a small Stirling engine running with several degree of temperature difference without power output. In this study, the design parameters to give maximum power are discussed. As results, the phase angle is about 100 degree, and compression ratio is 1.5% of the ratio of heat source temperatures at maximum power condition.

• International Journal of Precision Engineering and Manufacturing
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• v.8 no.1
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• pp.66-72
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• 2007

A computer code was developed to simulate the filling stage of an injection/compression molding process using a finite element method. The constitutive equation was the compressible Leonov model and the PVT relationship was assumed to follow the Tait equation. The flow-induced birefringence was related to the calculated flow stresses through the linear stress-optical law. Simulations of a disk under different processing conditions, including variations of the compression stroke and compression speed, were performed to determine their effects on the flow-induced birefringence. Simulated pressure traces were also compared to those obtained in conventional injection molding and with experimental data from the literature.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2004.10a
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• pp.65-69
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• 2004

A computer code was developed to simulate the filling stage of the injection/compression molding process by a finite element method. The constitutive equation used here was the compressible Leonov model. The PVT relationship was assumed to follow the Tait equation. The flow-induced birefringence was related to the calculated flow stresses through the linear stress-optical law. Simulations of a disk part under different processing conditions including the variation of compression stroke and compression speed were carried out to understand their effects on flow-induced birefringence. The simulated results were also compared with those by conventional injection molding and with experimental data from literature.

• Proceedings of the SAREK Conference
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• 2005.11a
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• pp.451-456
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• 2005

The mathematical model for the heat exchangers of absorber and desorber is made in the elementary control volume method and the thermodynamic properties of working fluid. water/ammonia mixture. are calculated by some fundamental subroutines in RefProp 7.0 and flash subroutines made by authors The simulation results show that two-stage cycle has higher COP than single stage if temperature lift is high: the performance of single stage compression cycle can be improved by increase of absorber pressure. but the performance of two-stage compression cycle can not be improved in this way : the compressor discharging temperature of two-stage compression is much lower than that of single stage cycle. which is very important to the safety operation of CA heat pump. Major parameter comparison between the cycles at their optimal configurations is also given.

• Structural Engineering and Mechanics
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• v.22 no.2
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• pp.241-262
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• 2006

NiTi-wire shape memory alloy (SMA) dampers, that utilize NiTi SMA wires to simultaneously damp tension, compression and torsion, was developed for structural control implementation in this study. First, eight reduced-scale NiTi-wire SMA dampers were constructed. Then tension, compression and torsion experiments using the eight reduced-scale NiTi-wire SMA dampers of different specification were done. The experimental results revealed all of the eight reduced-scale NiTi-wire SMA dampers had the ability to simultaneously supply tension-compression damping and torsion damping. Finally, mechanics analysis of the NiTi-wire SMA dampers was done based on a model of the SMA-wire restoring force and on tension-compression and torsion damping analysis. The damping analytical results were found to be similar to the damping experimental results.

• Structural Engineering and Mechanics
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• v.55 no.5
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• pp.931-951
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• 2015

To improve the durability and service life of reinforced concrete column such as bridge piers, an advanced composite column made of Ultra High Performance Cementitious Composites (UHPCC) permanent form is proposed. Based on elasticity plasticity theory, axial compression behavior of the composite column was studied theoretically. The first circumferential cracking load and ultimate limit loading capacity are derived for the composite column. Short composite column compression tests and numerical simulations using FEM method were carried out to justify the theoretical formula. The effects of UHPCC tube thickness on the axial compression behavior were studied. Using the established theoretical model and numerical simulation, the large dimension composite columns are calculated and analyzed with different UHPCC tube thickness. These studies may provide a reference for advanced composite column design and application.

• Proceedings of the KSRS Conference
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• 2003.11a
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• pp.997-999
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• 2003

The effects of JPEG2000 compression on automated DSM extraction by using the area-based matching are evaluated in this paper. The influences on DSM heights obtained via PCI Geomatics OrthoEngine module are investigated using a single stereo model of 1:5,000 scale aerial photography at image resolution of 20 ${\mu}$m. The experiment design of elevation errors are computed for a range of compression rates from 2:1 to about 100:1, and the DSM which generated from uncompressed image is used as ‘ground truth’ data for comparison. The experimental results show that the standard deviation ranged from 0.9m to 2.5m with the compression ratio from 2 to 100. It is also observed that there is no significant degradation on DSM accuracy up to the compression ratio of 33.

• Journal of Broadcast Engineering
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• v.27 no.7
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• pp.985-998
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• 2022

Even after the standardization of VVC completed in 2020, continuing efforts for developing even better video coding technology are still under way. In this context, the Joint Video Experts Group (JVET) is developing various video compression technologies under the name of enhanced compression beyond VVC capability which has reported BDBR gain of -6.75%, -14.05%, and -15.25% on its test model, ECM version 5.0, respectively in Y, Cb, and Cr channels by just having a few new or improved intra coding tools. The current activity has so far adopted 11 intra coding tools beyond VVC which can generate more sophisticated predictors, reduce signaling overhead, or combine various predictors. In this tutorial paper, we will review these techniques.