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991.
Quasi-isostatic hot pressing of the products of self-propagating high-temperature synthesis (SHS) is considered. The temperature regime, and the aggregate and structural state of the SHS products of the Ti ― C ― Ni system are studied. A block model of the deformed volume is presented; parameters of the virtual field of plastic flow velocities are determined and an energy equation in the form of a variation functional is determined. Rheological models of the non-linearly viscous SHS products and the rigidly-plastic loose shell are considered within which the dual mechanism of compaction and the local nature of dispersed material particle deformation are taken into account.
相似文献992.
Goitseone Malumbela Pilate Moyo Mark Alexander 《Construction and Building Materials》2009,23(11):3346-3351
This paper presents the results of an experimental study conducted to characterize the structural behaviour of reinforced concrete beams corroded whilst subjected to constant sustained service loads. Corrosion of tensile steel bars was induced by an accelerated corrosion process using a 5% solution of NaCl and a constant impressed current. Four RC beams were tested, each with a width of 153 mm, a depth of 254 mm and a length of 3000 mm. Beams were tested whilst under a load equivalent to 1%, 8% and 12% of the ultimate load. Longitudinal tensile and compressive strains were monitored during the corrosion process and used to determine the variation of the depth of the neutral axis, the curvature and the second moment of area of beams with the time of electrolysis. The results indicate that the longitudinal strains, the depth of the neutral axis and the curvature of beams depend on both the level of corrosion and the applied service load whilst the second moment of area is mostly influenced by the level of corrosion. 相似文献
993.
Narrow-bandwidth signals were applied to the end caps of an ion trap mass spectrometer to excite ions during collisional activation. Excitation waveforms were created from a single-frequency component and a random noise component using a multiplier circuit. Tandem and higher order mass spectrometry experiments (MS3) can be performed without optimization of the supplemental frequency applied to the end cap electrodes. The usefulness of this method of ion excitation is demonstrated using singly and multiply protonated peptide ions as well as sodium-cationized carbohydrates. 相似文献
994.
Pollatsek Alexander; Perea Manuel; Binder Katherine S. 《Canadian Metallurgical Quarterly》1999,25(4):1142
Assessed the effects of neighborhood size ("N")—the number of words differing from a target word by exactly 1 letter (i.e., "neighbors")—on word identification. In Exps 1 and 2, the frequency of the highest frequency neighbor was equated, and N had opposite effects in lexical decision and reading. In Exp 1, a larger N facilitated lexical decision judgments, whereas in Experiment 2, a larger N had an inhibitory effect on reading sentences that contained the words of Exp 1. Moreover, a significant inhibitory effect in Exp 2 that was due to a larger N appeared on gaze duration on the target word, and there was no hint of facilitation on the measures of reading that tap the earliest processing of a word. In Exp 3, the number of higher frequency neighbors was equated for the high-N and low-N words, and a larger N caused target words to be skipped significantly more and produced inhibitory effects later in reading, some of which were plausibly due to misidentification of the target word when skipped. Regression analyses indicated that, in reading, increasing the number of higher frequency neighbors had a clear inhibitory effect on word identification and that increasing the number of lower frequency neighbors may have a weak facilitative effect on word identification. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
995.
This paper reflects on existing caching concepts in proxies and stubs of component technologies and lines out their advantages and deficiencies. A new concept is introduced that averts proliferation of component stubs on client side while transparently providing efficient caching of attributes that doesn't require any changes to existing code at all. Common object-oriented design facilities and code generation tools are leveraged to support seamless integration of these caching concepts into the development cycle. 相似文献
996.
Alexander Fluegel 《Journal of the American Ceramic Society》2007,90(8):2622-2625
A large silicate glass density database including 6719 compositions, obtained from SciGlass© and other published sources, was systematically analyzed for agreement among room-temperature density data reported in the literature in 1030 different studies from various investigators. It was found that the literature data agree very well. Using just 101 of the initial 6719 degrees of freedom, 99.8% of the measured density data variance could be reproduced by an empirical polynomial model. The standard error of the developed model was 0.019 g/cm3 . 相似文献
997.
Investigated 2 reading models, focused attention and semantic preprocessing, in which nonfoveal information plays an important role. A reading experiment was conducted with 24 normally seeing members of a university community. Ss' eye movements were recorded as they read sentences, and a display change occurred before they fixated on a critical target word. In the target word location, 1 of 4 alternative previews was initially presented: the target word itself, a word semantically related to it, an unrelated word, and a nonword visually similar to the target. The various visual processes occurring during the experiment and the retinal regions involved are discussed. Results are inconsistent with the semantic preprocessing but consistent with the focused-attention model of reading. (French abstract) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
998.
999.
A novel real-time scheduler was developed to implement an interactive user interface for an existing state-of-the-art, hand-held
blood analyzer. A software-timer-based scheduler was designed and implemented and guaranteed schedulability analysis performed
to ensure that all hard execution deadlines could be met at run time. An execution bandwidth preservation mechanism that increases
the robustness and predictability of the scheduler is presented. The paper is a case study that describes the design and development
process from a point of view that emphasizes the importance of the systems integration issues that were encountered. 相似文献
1000.
Alexander D.S. Arbaugh W.A. Hicks M.W. Kakkar P. Keromytis A.D. Moore J.T. Gunter C.A. Nettles S.M. Smith J.M. 《IEEE network》1998,12(3):29-36
Active networks must balance the flexibility of a programmable network infrastructure against the safety and security requirements inherent in sharing that infrastructure. Furthermore, this balance must be achieved while maintaining the usability of the network. The SwitchWare active network architecture is a novel approach to achieving this balance using three layers: active packets, which contain mobile programs that replace traditional packets; active extensions, which provide services on the network elements and can be dynamically loaded; and a secure active router infrastructure, which forms a high-integrity base on which the security of the other layers depends. In addition to integrity checking and cryptography-based authentication, security in our architecture depends heavily on verification techniques from programming languages, such as strong type checking 相似文献