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71.
Luqi Berzins V. Yeh R. 《IEEE transactions on pattern analysis and machine intelligence》1988,14(10):1409-1423
PSDL is a language for describing prototypes of real-time software systems. It is most useful for requirements analysis, feasibility studies, and the design of large embedded systems. PSDL has facilities for recording and enforcing timing constraints, and for modeling the control aspects of real-time systems using nonprocedural control constraints, operator abstractions, and data abstractions. The language has been designed for use with an associated prototyping methodology. PSDL prototypes are executable if supported by a software base containing reusable software components in an underlying programming language (e.g. Ada) 相似文献
72.
Lin Chih-Yang Muchtar Kahlil Lin Jia-Ying Sung Yu-Hsien Yeh Chia-Hung 《Multimedia Tools and Applications》2017,76(7):9759-9783
Multimedia Tools and Applications - The privacy-preserving moving object detection has drawn a lot of interest lately. Nevertheless, current approaches use Paillier’s scheme for encryption... 相似文献
73.
Rolling Friction Enhanced Free‐Standing Triboelectric Nanogenerators and their Applications in Self‐Powered Electrochemical Recovery Systems 下载免费PDF全文
Min‐Hsin Yeh Hengyu Guo Long Lin Zhen Wen Zhaoling Li Chenguo Hu Zhong Lin Wang 《Advanced functional materials》2016,26(7):1054-1062
Heavy metals contained in wastewater are one of the most serious pollutions in natural resources. A self‐powered electrochemical recovery system for collecting Cu ions in wastewater by incorporating a rolling friction enhanced freestanding triboelectric nanogenerator (RF‐TENG) is developed here. The RF‐TENG utilizes integrated cylindrical surfaces using the conjunction of rolling electrification and freestanding electrostatic induction, which shows outstanding output performance and ultrarobust stability. By using the kinetic energy of flowing water, a collection efficiency of up to 80% for Cu2+ ions in wastewater has been achieved. Self‐powered electrochemical systems are one of the most promising applications of TENGs for independent and sustainable driving of electrochemical reactions without the need for any additional power supply. This research is a substantial advancement towards the practical applications of triboelectric nanogenerators and self‐powered electrochemical systems. 相似文献
74.
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
75.
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
76.
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
77.
Li Cui Li-ping Xu Fang-Chang Tsai Ping Zhu Tao Jiang Jen-taut Yeh 《Journal of Polymer Research》2011,18(6):1301-1313
Oxygen scavenging plastic can react with oxygen that was trapped in the packaging materials or permeated into the packages,
and then, extend the shelf life of food contained in packages. Sodium ascorbate (SA) and modified iron (MFe) compounds were
chosen as the main components of oxygen scavengers to prepare the oxygen scavenging LDPE plastics. However, the widely used
hydrophobic LDPE packaging material will slow down the oxygen depletion rate of these oxygen scavenger compounds. So glucose
was used to modify the hydrophobic property of LDPE to improve the oxygen depletion properties of LDPE oxygen scavenging plastic.
The oxygen depletion efficiency of L95[SAx(MFe)y]5 series samples improved initially as the weight ratios of SA/MFe increase, and reached the best as the weight ratios of SA/MFe
approach 7/3. After modifying LDPE with glucoses, the oxygen depletion efficiency of each ML95[SAx(MFe)y]5 specimen improved even better than that of the corresponding L95[SAx(MFe)y]5 specimen with the same loading of oxygen scavenger compound, wherein the oxygen depletion efficiency of ML95[SAx(MFe)y]5 series specimens reached the best as the weight ratios of SA/MFe approach 1/9. In consistent with the oxygen depletion properties
found in the previous section, the peroxide values of modeled food samples tested in the airtight flask with L95[SAx(MFe)y]5 and ML95[SAx(MFe)y]5 series samples reduce consistently as their oxygen depletion properties improve. In order to understand the interesting oxygen
depletion properties of L95[SAx(MFe)y]5 and ML95[SAx(MFe)y]5 series samples, Fourier transform infrared spectroscopy, scanning electron microscope and energy dispersive X-rays analysis
of these samples were performed. 相似文献
78.
Tsung-Kuang Yeh Ming-Han Tsai Mei-Ya Wang Chen-Kuo Weng 《Journal of Applied Electrochemistry》2008,38(11):1495-1500
In the preparation of copper interconnects in the conductor pattern of a printed circuit board (PCB), wet etching processes
are commonly adopted for creating patterns of high-density interconnects. Currently available techniques of immersion and
spray etching could lead to poorly shaped wires due to complex flow fields or the disturbing puddling effect. A modified technique
of arrayed jet-stream etching was developed in this work, aiming at producing well-defined copper interconnects on a PCB in
a significantly shorter time. The results were appealing in that copper interconnects of 35/140 μm (thickness/width) exhibiting
etching factors of greater than 6 were obtained in 20 s, much better than the conventional ones with etching factors of 3
to 5 and etching times of at least 2 min. In addition, uniformly etched copper interconnects with less than 20 μm undercuts
were observed on one etching line. One additional point to note is that no banking agents or inhibitors as commonly seen in
conventional etching techniques were needed in this new processing method. 相似文献
79.
In this study, the melting behavior of isothermally crystallized polytri‐ methylene terephthalate (PTT) was investigated. Multiple melting behaviors in DSC heating trace were found because two populations of lamellar stacks were formed during primary crystallization and the recrystallization at heating process, respectively. This fact could be also confirmed from the result of optical microscopy observation. The Hoffman–Weeks equation was applied to obtain equilibrium melting temperature (T). The T value of PTT is about 525 K, which is 10 K higher than that reported. Combining the enthalpy of fusion from the DSC result and the degree of crystallinity from WAXD result, the value of the equilibrium‐melting enthalpy ΔH was deduced to be approximately 28.8 kJ mol?1. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 83: 2426–2433, 2002 相似文献
80.
Shu‐Kai Yeh Chien‐Hsiung Huang Chi‐Chun Su Kuo‐Chung Cheng Tsu‐Huang Chuang Wen‐Jeng Guo Sea‐Fue Wang 《Polymer Engineering and Science》2013,53(10):2061-2072
In this study, polystyrene/nanographite nanocomposite foams were made by different compounding methods, such as direct compounding, pulverized sonication compounding, and in situ polymerization, to understand the effect of the process variables on the morphology of the nanocomposites and their foam. The foam was made by batch foaming using CO2 as the blowing agent. Various foaming pressures and temperatures were studied. The results indicated that the cell size decreased and the cell morphology was improved with the advanced dispersion of the nanoparticles. Among the three methods, the in situ polymerization method provided the best dispersion and the resulting nanocomposite foam had the finest cell size and the highest cell density. In addition, adding nanoparticles as a nucleating agent can make foams of similar cell size and cell density at a much lower foaming pressure. This result can be explained by the classical nucleation theory. This discovery could open up a newroute to produce microcellular foams at a low foaming pressure. POLYM. ENG. SCI., 53:2061–2072, 2013. © 2013 Society of Plastics Engineers 相似文献