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Choi, Kyu-Chon;Lee, Jae-Seok
- Journal of the Computational Structural Engineering Institute of Korea
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- v.22 no.1
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- pp.1-13
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- 2009
A study for the nonlinear solution strategies to predict the ultimate behavior of a curved PSC cable-stayed bridge with complex geometry and highly nonlinear characteristics is presented. The load and displacement control strategies are used and found to be stable for the nonlinear solution of the PSC bridge up to the moderately excessive load. The ultimate analysis of curved PSC cable-stayed bridge using these solution strategies is not converged due to the propagation of the cracks in the wide range of the concrete elements and excessive variation of the stresses in the concrete elements and cables according to the complex geometry. The load control strategy using scale-down of the unbalanced loads is proposed as an alternative method for the case that the solution is not converged due to the severe nonlinearities involved in the PSC structures like a curved PSC cable-stayed bridge. Through the ultimate analysis of the PSC girder, the accuracy and the stability of the proposed solution strategies are evaluated. Finally, the numerical results for the ultimate analysis of the curved PSC cable-stayed bridge using scale-down of the unbalanced loads are compared with those obtained from other investigator. The validity of the proposed nonlinear solution strategy is demonstrated fairly well.
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Park, Tae-Jung;Woo, Jun-Myung;Kim, Chang-Hun
- Journal of the Institute of Electronics Engineers of Korea CI
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- v.48 no.1
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- pp.90-100
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- 2011
We present a parallel bi-conjugate gradient (Bi-CG) matrix solver for large scale Bio-FET simulations based on recent graphics processing units (GPUs) which can realize a large-scale parallel processing with very low cost. The proposed method is focused on solving the Poisson equation in a parallel way, which requires massive computational resources in not only semiconductor simulation, but also other various fields including computational fluid dynamics and heat transfer simulations. As a result, our solver is around 30 times faster than those with traditional methods based on single core CPU systems in solving the Possion equation in a 3D FDM (Finite Difference Method) scheme. The proposed method is implemented and tested based on NVIDIA's CUDA (Compute Unified Device Architecture) environment which enables general purpose parallel processing in GPUs. Unlike other similar GPU-based approaches which apply usually 32-bit single-precision floating point arithmetics, we use 64-bit double-precision operations for better convergence. Applications on the CUDA platform are rather easy to implement but very hard to get optimized performances. In this regard, we also discuss the optimization strategy of the proposed method.
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Jeong, Sang Hwa;Shin, Jung Ah;Kim, In Hwan;Kim, Byung Hee;Lee, Jun Soo;Lee, Ki Teak
- Journal of the Korean Society of Food Science and Nutrition
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- v.43 no.8
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- pp.1257-1263
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- 2014
Different fat extraction methods such as the Rose-Gottlieb, Folch, and hydrolytic methods were compared in terms of their fatty acid contents of milk powder. Contents of total saturated fatty acids by the Rose-Gottlieb, Folch, and hydrolytic methods were 8.578, 8.302, and 8.711 g/100 g milk powder while contents of total unsaturated fatty acids by the Rose-Gottlieb, Folch, and hydrolytic methods were 11.513, 11.143, and 11.669 g/100 g milk powder, respectively. These results suggest that the hydrolytic method has a similar fatty acid composition as the well-known Rose-Gottlieb method. In uncooked chicken, total fatty acid contents of breast, gamb, and wing were 6.302, 8.313, and 11.346 g/100 g, respectively. Among different cooking methods, frying increased content of total trans fatty acids up to 0.034 (breast), 0.112 (gamb), and 0.123 g/100 g (wing).
https://doi.org/10.3746/jkfn.2014.43.8.1257 인용 PDF KSCI