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991.
Summary. Looking at rational mixture theories within the context of a new perspective, this work aims to put forward a proposal for
an Eshelbian approach to the nonlinear mechanics of a constrained solid-fluid mixture, made up of an inhomogeneous poroelastic
solid and an inviscid compressible fluid, which do not undergo any chemical reaction.
Received July 26, 2001; revised May 15, 2002 Published online: January 16, 2003 相似文献
992.
Crupi F. Kaczer B. Groeseneken G. De Keersgieter A. 《Electron Device Letters, IEEE》2003,24(4):278-280
In this letter, we report new findings in the relation between channel hot-carrier (CHC) degradation and gate-oxide breakdown (BD) in short-channel nMOSFETS biased at V/sub G/>V/sub D/. We observe that the time-to-BD is strongly reduced in the hot carrier regime and that although the channel hot-electron injection into the oxide occurs mainly at the drain side, stress-induced leakage current (SILC) generation and oxide BD always occur at the source side. The results of these measurements indicate that not solely the energy of the injected electrons but also the oxide electric field is determinant in the oxide BD process. 相似文献
993.
The distribution of ergosterol in different parts of shiitake mushrooms was studied in order to optimize the conversion of ergosterol to vitamin D2 during drying. The effect of moisture on the conversion of ergosterol to vitamin D2 was also investigated by adjusting the moisture content of fresh mushrooms to different levels in a large vacuum desiccator and subjecting them to UV irradiation at 290-320 nm wavelength, for 2 h. The moisture, ergosterol and vitamin D2 contents were determined using standard procedures. It was found that the ergosterol content on a dry matter basis of fresh shiitake mushroom was highest in the gills (10.6 ± 0.99 mg/g DM), followed by the cap or pileus (5.34 ± 0.64 mg/g DM) and was least in the stalk or stipe (2.97 ± 0.56). The moisture content had a marked influence on the conversion of ergosterol to vitamin D2, the best conversion taking place at a moisture content of about 70% on a wet basis. 相似文献
994.
Web services are emerging as a promising technology for effectively automating interorganizational interactions. However, despite the growing interest, several issues remain to be addressed to provide Web services with benefits similar to what traditional middleware brings to intraorganizational application integration. We identify a framework that builds on current standards to help developers define extended service models and richer Web service abstractions. The framework's main feature is a conversation metamodel derived from our analysis of e-commerce portal sites. 相似文献
995.
Osasere Faraday F. Orumwense 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》1994,60(4):405-411
Dispersion–flocculation studies on a Goethite–clay system using flocculants were carried out as a function of flocculant concentrations, pH of slurry, time of agitation and dispersant dosage. Also, the effects of pH and polymer concentrations on the adsorption behaviour of the system were investigated. Results show that well flocculated goethite was preferentially obtained from 4% goethite/kaolinite clay suspensions, with 50 ppm causticised starch in the slurry at pH values of 3–11·5 and with 50 ppm polyacrylamide at pH values of 3–8. Good flocs were also obtained on flocculation of the goethite suspension with 50 ppm polyacrylamide at pH values of 5–7, while the kaolinite suspension did not respond to the same dosage of causticised starch in the same pH range. Results further reveal that for the goethite/kaolinite suspension, the best results was obtained with 50 ppm polyacrylamide at pH values of 7–10. Based on the data generated in the study, it was concluded that causticised starch is a better flocculant than polyacrylamide for goethite suspensions although polyacrylamide is an excellent flocculant for kaolinite suspensions. 相似文献
996.
A. V. Banshchikov L. A. Burlakova V. D. Irtegov M. A. Novikov 《Cybernetics and Systems Analysis》1992,28(1):119-127
Algorithms are proposed that construct first integrals and Lyapunov functions for stability analysis of stationary solutions of differential equations describing mechanical systems of linked bodies.Translated from Kibernetika i Sistemnyi Analiz, No. 1, pp. 138–148, January–February, 1992. 相似文献
997.
998.
N. I. Koronkevich D. A. Eliseev S. V. Yasinskii 《Power Technology and Engineering (formerly Hydrotechnical Construction)》1994,28(8):411-415
Translated from Gidrotekhnicheskoe Stroitel'stvo, No. 8, pp. 1–5, August, 1994. 相似文献
999.
Edwin P. D. Pednault 《Computational Intelligence》1988,4(3):356-372
This paper presents a method of solving planning problems that involve actions whose effects change according to the situations in which they are performed. The approach is an extension of the conventional planning methodology in which plans are constructed through an iterative process of scanning for goals that are not yet satisfied, inserting actions to achieve them, and introducing subgoals to these actions. This methodology was originally developed under the assumption that one would be dealing exclusively with actions that produce the same effects in every situation. The extension involves introducing additional subgoals to actions above and beyond the preconditions of execution normally introduced. These additional subgoals, called secondary preconditions, ensure that the actions are performed in contexts conducive to producing the effects we desire. This paper defines and analyzes secondary preconditions from a mathematically rigorous standpoint and demonstrates how they can be derived from regression operators. 相似文献
1000.
M F Haisman 《Ergonomics》1988,31(7):1049-1063