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61.
Digital rights management system with user privacy,usage transparency,and superdistribution support
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Chih‐Ta Yen Horng‐Twu Liaw Nai‐Wei Lo 《International Journal of Communication Systems》2014,27(10):1714-1730
In the modern world, digital content has been massively produced, distributed, and consumed by human beings; consequently, how to protect the rights and benefits of content consumers, producers, and distributors has become a crucial issue. One promising solution is to design a full‐fledged digital rights management (DRM) system. In this study we introduce a new design on the digital rights management system providing user privacy, usage transparency, and superdistribution. A comprehensive set of DRM processing functions and corresponding mechanisms are developed in our system to support various business process requirements. Superdistribution support is embedded in our system design. A prototype is implemented to verify our system design. To protect consumer privacy, a temporary identity is generated for each consumer using the KryptoKnight protocol. Elliptic curve cryptography‐based encryption scheme is adopted for messages transmitted among servers and client over an unsecure communication channel. For usage transparency, a user‐friendly DRM client package (software) is introduced in the proposed DRM system to achieve content protection and support user convenience in usage.Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
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Chorng-Wei Liaw Leaf Yeh Ming-Jang Lin Chrong Jung Lin 《Electron Device Letters, IEEE》2007,28(8):737-739
In this letter, a novel type of high-voltage n-channel junction field-effect transistor (JFET) was designed using a conventional n-channel laterally diffused metal-oxide-semiconductor (n-LDMOS) without changing any step in the process. High-voltage JFET can be a start-up device in power factor correction, dc-ac converters, and ac-dc converters for providing a self-powered circuit and minimizing standby power losses without gate control because of its negative threshold voltage. Experimental results show that an n-LDMOS with this JFET structure can achieve a reverse blocking voltage of more than 700 V with very low leakage current. The pinch-off voltage can be designed by changing n-well width to meet the circuit requirement. 相似文献
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Teen-Hang Meen Ying-Chung Chen Ken-Whie Liaw Hung-Duen Yang 《Journal of the American Ceramic Society》1993,76(8):1948-1952
X-ray diffraction patterns show that most samples of Y1-x Prx Ba2 Cu4 O8 examined in the present study contained a single YBa2 Cu4 O8 (1-2-4) superconductive phase for x<0.7.Lattice parameters a and b increased with Pr concentration, suggesting that most of the Pr is trivalent in Y1-x Prx- Ba2 Cu4 O8 . The zero-resistance temperature, T co , decreases monotonically from 80 K at x=0 to 12 K at x=0.65, and superconducting transition widths tend to broaden for x>0. The room-temperature resistivity changes linearly until x=0.7 and increases abruptly at x=-0.75. The critical concentration, xcr , thus was estimated to be 0.7. The effective magnetic moments of Pr in Y 1-x Prx Ba2 Cu4 O8 were 3.63., 3.35, and 3.23, μB for x=0.2, 0.4 and 0.6, respectively. In the R0.8 Pr0.2 Ba2 Cu4 O8 system, the depression of Tc weakly depends on the ionic radius of rare-earth elements. Similarities and differences between Y 1-x Prx Ba2 Cu4 O8 and Y1-x Prx- Ba2 Cu3 O7-y also were noted and are discussed in this paper. 相似文献
65.
J Brittingham D Liaw R Liddell M McHugh P McCue KM McHugh 《Canadian Metallurgical Quarterly》1997,65(3):113-122
Monoclonal antibodies derived from the actin multigene family are routinely used as an adjunct to morphologic diagnoses of smooth muscle tumors. Northern blot analysis was performed on 60 surgical resections utilizing isoactin-specific cDNAs. A comparison of this analysis to immunohistochemical studies demonstrated that actin-specific monoclonal antibodies represent reliable markers of the smooth muscle lineage. Smooth muscle neoplasms showed a unique pattern of gamma-smooth muscle isoactin gene expression, providing a potentially valuable molecular adjunct to the morphologic diagnosis of uterine smooth muscle tumors. 相似文献
66.
B. Yang G. Wang W. H. Peter P. K. Liaw R. A. Buchanan D. E. Fielden Y. Yokoyama J. Y. Huang R. C. Kuo J. G. Huang D. L. Klarstrom 《Metallurgical and Materials Transactions A》2004,35(1):15-23
A high-speed and high-sensitivity thermographic-infrared (IR) imaging system has been used for nondestructive evaluation of
specimen-temperature evolutions during high-cycle fatigue experiments. The relationship among the temperature, stress-strain
state, and fatigue behavior is discussed. Both thermodynamics and heat-transfer theories are applied to model and quantify
the observed temperature variations during fatigue. The predicted and measured temperature evolutions and inelastic strains
during fatigue were found to be in good agreement. During fatigue experiments, in-situ observations as well as qualitative and quantitative analyses of Lüders-band evolutions, crack propagation, plastic zones,
and final fracture have been performed by thermography, which can open up wide applications of thermography in detecting the
in-situ heat-related processes, including mechanical damages and phase transformations, of materials and structural components. 相似文献
67.
P. K. Liaw W. A. Logsdon J. A. Begley 《Metallurgical and Materials Transactions A》1989,20(10):2069-2085
The fatigue crack growth rate (FCGR) properties of SA508 C1 2a and SA533 Gr A C1 2 pressure vessel steels and the corresponding
automatic submerged are weldments were developed in a high-temperature pressurized water (HPW) environment at 288 °C (550°F)
and 7.2 MPa (1044 psi) at load ratios of 0.02 and 0.50. The HPW enviromment FCGR properties of these pressure vessel steels
and submerged arc weldments were generally conservative, compared with the approrpriate American Society of Mechanical Engineers
(ASME) Section XI water environmental reference curve. The growth rate of fatigue cracks in the base materials, however, was
considerably faster in the HPW environment than in a corresponding 288°C (550°F) base line air environment. The growth rate
of fatigue cracks in the two submerged are weldments was also accelerated in the HPW environment but to a significantly lesser
degree than that demonstrated by the corresponding base materials. In the air environment, fatigue striations were observed,
independent of material and load ratio, while in the HPW environment, some intergranular facets were present. The greater
environmental effect on crack growth rates displayed by the base materials, as compared with the weldments, was attributed
to a different sulfide composition and morphology. 相似文献
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