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101.
Liang‐Wei Zheng Gwo‐Long Li Mei‐Juan Chen Chia‐Hung Yeh Kuang‐Han Tai Jian‐Sheng Wu 《ETRI Journal》2013,35(3):469-479
This paper proposes an efficient computation‐aware mode decision and search point (SP) allocation algorithm for spatial and quality scalabilities in Scalable Video Coding. In our proposal, a linear model is derived to allocate the computation for macroblocks in enhancement layers by using the rate distortion costs of the base layer. In addition, an adaptive SP decision algorithm is proposed to decide the number of SPs for motion estimation under the constraint of the allocated computation. Experiment results demonstrate that the proposed algorithm allocates the computation resource efficiently and outperforms other works in rate distortion performance under the same computational availability constraint. 相似文献
102.
This study investigates electromigration in Bi2Te3 thermoelectric (TE) material systems and the effectiveness of the diffusion barrier under current. The Peltier effect on the interfacial reaction was decoupled from the effect of electromigration. After connecting p- and n-type Bi2Te3 to Sn3Ag0.5Cu (SAC305) solders, different current densities were applied at varying temperatures. The Bi2Te3 samples were fabricated by the spark plasma sintering technique, and an electroless nickel-phosphorous (Ni-P) layer was deposited at the solder/TE interfaces. The experimental results confirm the importance of the Ni diffusion barrier in joint reliability. Intermetallic compound layers (Cu,Ni)6Sn5 and NiTe formed at the solder/Ni-P and Ni-P/substrate interfaces, respectively. The experimental results indicate that the mechanism of NiTe and (Cu,Ni)6Sn5 compound growth was dominated by the Peltier effect at high current density. When the current density was low, the growth of NiTe was affected by electromigration but the changes of thickness for (Cu,Ni)6Sn5 were not obvious. 相似文献
103.
104.
An investigation of the gasoline permeation resistance of the as‐blow‐molded and annealed polyethylene, polyethylene (PE)/polyamide (PA), and polyethylene/modified polyamide (MPA) bottles is reported. The gasoline permeation resistance improves dramatically after blending PA and MPA barrier resins in PE matrices during blow‐molding, and the order of barrier improvement corresponds to the order of barrier improvement of the barrier resins added in PE. Somewhat unexpectedly, the gasoline permeation rates of the annealed PE and/or PE/PA bottles annealed at 90°C or higher temperatures increase significantly with the annealing temperature and time. On the contrary, the gasoline permeation resistance of the annealed PE/MPA bottles increase significantly as the annealing temperature and/or time increase. For instance, the gasoline permeation rate of the PE/MPA bottle annealed at 120°C for 32 h is about 190 times slower than that of the as‐blow‐molded PE bottle. Further investigations found that, after blending the MPA and PA barrier resins in PE matrices, the relatively nonpolar hydrocarbon components present in the gasoline fuels were significantly blocked, without permeation during the permeation tests, in which the as‐blow‐molded PE/MPA bottle inhibited the permeation of hydrocarbon components more successfully than did the as‐blow‐molded PE/PA bottle. In contrast, the amounts of polar components that permeated through the as‐blow‐molded PE/PA and PE/MPA bottles were very small and about the same as the amount that permeated through the as‐blow‐molded PE bottle. Possible mechanisms accounting for these interesting behaviors are proposed in this study. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 81: 2827–2837, 2001 相似文献
105.
Thomas M. Yeh Jacob G. Dickinson Allison Franck Suljo Linic Levi T. Thompson Jr Phillip E. Savage 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2013,88(1):13-24
One of the promising avenues for biomass processing is the use of water as a reaction medium for wet or aquatic biomass. This review focuses on the hydrothermal catalytic production of fuels and chemicals from aquatic biomass. Two different regimes for conversion of aquatic biomass in hydrothermal conditions are discussed in detail. The first is hydrothermal liquefaction, and the second is hydrothermal gasification. The goals of these processes are to produce liquid‐fuel‐range hydrocarbons and methane or hydrogen, respectively. The catalytic upgrading of biocrude resulting from noncatalytic liquefaction and the stability and degradation of catalysts in high temperature water are also discussed. The review concludes with a brief discussion of the outlook for and opportunities within the field of hydrothermal catalytic valorization of biomass. Copyright © 2012 Society of Chemical Industry 相似文献
106.
H.M. Yeh 《Progress in Nuclear Energy》2009,51(6-7):658-662
The effect of plate aspect ratio on the performance of deuterium recovery from the separation of water–isotope mixture in thermal-diffusion columns of a countercurrent-flow Frazier scheme was investigated. The equations for the optimal plate aspect ratios and the corresponding maximum recovery and maximum production rate were derived. Considerable improvement in performance is obtained when thermal-diffusion columns are operated at the optimal plate aspect ratio. Further improvement can be achieved if the scheme is connected and operated in countercurrent flow, instead of concurrent flow. 相似文献
107.
Hsien‐Hung Herman Yeh 《Construction Management & Economics》2013,31(4):329-340
Prior studies have found that firms may deviate from the target capital structure in the short run and adjust towards the target in the long run. However, little attention has been given to the adjustment behaviour of capital structure in the construction industry over the business cycles, in particular within the context of emerging markets. The partial adjustment model with the GMM (i.e. generalized method of moments) estimation is used to examine the adjustment behaviour of capital structure in the construction industry within the context of Taiwan during the period 1982 to 2007. The results suggest that, first, the average rate of adjustment is 26.3% of the adjustment gap between the target debt ratios and the previous debt ratios for firms in the construction industry of Taiwan. However, the average rate of adjustment towards the target debt ratios has slowed down after the Asian financial crisis of 1997. Secondly, firms with the financial constraint of over‐leverage relative to the target debt ratios have lower debt ratios than those firms with the financial constraint of under‐leverage. In addition, the difference in debt ratios between firms with the financial constraint of over‐leverage and under‐leverage has become narrower after the Asian financial crisis. Lastly, the findings suggest that macroeconomic conditions do not have a significant, negative effect on debt ratios. 相似文献
108.
In this study, the coloration mechanism of isotactic poly(1-butene) (iPB) in o-xylene and o-xylene/ethyl alcohol mixture gels were carried out. iPB gel becomes yellow because of transmitted light or blue because of reflected light. Changing the temperature, solvent composition, or even the thickness of samples of this gel continuously changes its color to blue, violet, purple, red, and yellow. Structural characterization, electron microscopy, and transmittance measurements were carried out for iPB dissolved in o-xylene to form a three-dimensional sponge-like network with different mesh sizes under various conditions. Subsequently, the relative refractive index between the solvent and gel network produces incoherent Tyndall blue scattering. Finally, color change due to variations in solvent composition or temperature contributes to the interplay between the refractive index of network structure nnetwork and solvent ns. For a Tyndall medium with ns/nnetwork >1, normal reflection creates a blue gel; when ns/nnetwork ≒1, strong transmittance of light passing through the medium leads to a yellowish gel. This is the first report on the concept of structural color for polymeric physical gel systems. 相似文献
109.
TaB- and TaB2–Al2O3 in situ composites were fabricated by thermite-incorporated combustion synthesis from the powder mixtures of different combinations, including Ta2O5–Al–B, Ta2O5–Al–B2O3–B, and Ta2O5–B2O3–Al. Effects of excess boron were studied on the combustion dynamics and phase constituents of final products. For the B2O3-containing samples, the reaction was less exothermic and aluminothermic reduction of Ta2O5 and B2O3 was less complete, resulting in the deficiency of boron and the presence of TaO2 and Ta. For the samples containing elemental boron, the occurrence of borothermic reduction of Ta2O5 also caused the loss of boron. Experimental evidence showed that boron in excess of the stoichiometric amount substantially enhanced the formation of tantalum borides, which in turn facilitated the reduction of Ta2O5 by Al. Consequently, the samples rich with boron in the molar proportions of Ta2O5:Al:B=3:10:9 and 3:10:16 (i.e., B/Ta=1.5 and 2.67) were found to be the optimum stoichiometries of producing TaB- and TaB2–Al2O3 composites through a self-sustaining combustion process. 相似文献
110.
Yuh-Ching Gau Tsung-Jang Yeh Chin-Mu Hsu Samuel Yien Hsiao Hui-Hua Hsiao 《International journal of molecular sciences》2022,23(6)
Multiple myeloma is a hematologic malignancy of plasma cells that causes bone-destructive lesions and associated skeletal-related events (SREs). The pathogenesis of myeloma-related bone disease (MBD) is the imbalance of the bone-remodeling process, which results from osteoclast activation, osteoblast suppression, and the immunosuppressed bone marrow microenvironment. Many important signaling cascades, including the RANKL/RANK/OPG axis, Notch signaling, the Wnt/β-Catenin signaling pathways, and signaling molecules, such as DKK-1, sclerostin, osteopontin, activin A, chemokines, and interleukins are involved and play critical roles in MBD. Currently, bisphosphonate and denosumab are the gold standard for MBD prevention and treatment. As the molecular mechanisms of MBD become increasingly well understood, novel agents are being thoroughly explored in both preclinical and clinical settings. Herein, we will provide an updated overview of the pathogenesis of MBD, summarize the clinical management and guidelines, and discuss novel bone-modifying therapies for further management of MBD. 相似文献