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1.
A micromechanics analysis is performed for the determination of the five independent elastic moduli of unidirectional fiber composites. By considering viscoelastic phases and by using the correspondence principle and the inversion of the Laplace transform, the five time-dependent functions which characterize the effective behavior of viscoelastic composites are established. The predicted time-dependent behavior is applied for the analysis of viscoelastic laminated plates. The resulting viscoelastic effects are shown, and comparison between the results obtained within the classical laminated plate theory and the first-order shear deformation theory is discussed. 相似文献
2.
Jacob Hooker David Hinks Gerardo Montero Christopher Conlee 《Coloration Technology》2002,118(6):273-276
The synthesis of azo dyes via a conventional aqueous-based diazotisation and coupling reaction requires the use of relatively high concentrations of mineral acids, which leads to high electrolyte concentrations in wastewater. Reported in this paper is an environmentally benign one-pot method for the synthesis of a nonionic azo dye, N,N -diethyl- N -{4-[( E )-(4-nitrophenyl)diazenyl]phenyl}amine, in supercritical carbon dioxide without using a mineral acid. The product yield increased significantly with temperature, with 91% theoretical yield afforded at 80 °C. The pressure of the system had little influence on product yield. 相似文献
3.
Ron Kimmel Doron Shaked Michael Elad Irwin Sobel 《IEEE transactions on image processing》2005,14(6):796-803
Gamut mapping deals with the need to adjust a color image to fit into the constrained color gamut of a given rendering medium. A typical use for this tool is the reproduction of a color image prior to its printing, such that it exploits best the given printer/medium color gamut, namely the colors the printer can produce on the given medium. Most of the classical gamut mapping methods involve a pixel-by-pixel mapping and ignore the spatial color configuration. Recently proposed spatial-dependent approaches for gamut mapping are either based on heuristic assumptions or involve a high computational cost. In this paper, we present a new variational approach for space-dependent gamut mapping. Our treatment starts with the presentation of a new measure for the problem, closely related to a recent measure proposed for Retinex. We also link our method to recent measures that attempt to couple spectral and spatial perceptual measures. It is shown that the gamut mapping problem leads to a quadratic programming formulation, guaranteed to have a unique solution if the gamut of the target device is convex. An efficient numerical solution is proposed with promising results. 相似文献
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F F?ndrich AM Waaga J Schr?der E Schweizer A Schmid S Jacob HH Wacker P Schroeder 《Canadian Metallurgical Quarterly》1995,27(2):1553-1554
7.
This study addressed the issue of adjustment among Holocaust survivors by multidimensional assessment of subjective well-being (SWB). Participants were Israeli Holocaust survivors incidentally included in a life-span study (Group 1; n?=?466) or purposely approached for studying Holocaust survivors (Group 2; n?=?178). Comparison participants had immigrated to Israel before World War II, with their parents either undergoing (Group 3; n?=?270) or not undergoing the Holocaust (Group 4; n?=?388); other comparison participants had immigrated after the war with parents not undergoing the Holocaust (Group 5; n?=?166). Results showed that Group 1 scored lower than Group 2, mainly in positive affect. Group 1 scored lower than Group 4, and to a lesser extent also lower than Groups 3 and 5, mainly in aging-related themes of SWB. The study suggests that long-term effects of the Holocaust on the survivors' SWB are traceable but require a differential approach to the study groups and to the facets of SWB. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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Masetti F. Gabriagues J.-M. Guittard O. Jacob J.-B. 《Lightwave Technology, Journal of》1995,13(11):2142-2151
In future broadband communication networks the interest for purely photonic switches is due to the bandwidth mismatch between optical transmission networks and electronic switching nodes. Photonic ATM switching fabrics mainly based on wavelength-switching stages are therefore being studied, to implement high capacity switches with also concentration, multiplexing and demultiplexing functions, using state-of-the-art photonic technology. The architecture of an ATM photonic access concentrator is described in this paper, illustrating the design and implementation of its basic subsystems, the traffic concentrator and the cell multiplexer. The design guidelines are outlined in detail referring to an example, where 128 user lines at 622 Mb/s are given access to 4 outlets at 2.488 Gb/s. The corresponding implementation, based on the systematic use of cell wavelength encoding, makes use either of well-known photonic components, such as Fabry-Perot filters, fiber delay lines, splitters and combiners, either of recently developed devices, like high-speed optical gates and tunable filters and lasers. Finally, the system feasibility is demonstrated presenting the results obtained on a reduced size and speed experimental setup of the cell multiplexer 相似文献
10.
Enhanced C (EC) is a set-oriented, extensible, C-like language. EC uses data abstractions to define new types. These data abstractions, called clusters, are macro-like devices that perform substitution on the typed syntax tree. Debugging programs that use clusters raise problems that are not encountered in ordinary programming languages. At compile time there is a need to determine and report whether the macro expansion will result in a legal program before this expansion actually takes place. At run-time the problems are how to account for replaced statements and how to handle variables whose types have been established by the clusters, variables that disappear, or variables whose names have been changed. This article presents these problems and their solutions as implemented by the EC compiler and the EC symbolic debugger. Similar debugging problems appear in other languages: The need to handle variables at run time is common to all languages that support data abstraction even if the abstractions are procedure oriented; also, a mild form of the problem of the replaced statement appears in inline procedure substitution of Ada. The solutions developed for the EC debugger apply to these cases as well. 相似文献