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41.
Randall J. Charbeneau Andrew D. Henderson Lee C. Sherman 《Canadian Metallurgical Quarterly》2006,132(5):474-481
This paper presents a versatile two-parameter model describing the hydraulic performance of highway culverts operating under inlet control for both unsubmerged and submerged conditions. Applications show that the model can accurately represent the Federal Highway Administration (FHwA) performance curves (which use four parameters) for a range of culvert types and materials. Laboratory data from an investigation of the hydraulic performance of single- and multiple-barrel low-headwater box culverts are also used, and the resulting model predicts a smaller culvert size as compared with the FHwA equations for a given design discharge. Design recommendations are presented for low-headwater box culverts. 相似文献
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[Correction Notice: An erratum for this article was reported in Vol 135(4) of Journal of Experimental Psychology: General (see record 2006-20327-004). This article was inadvertently printed with the incorrect title. A clarification regarding the correct title is provided in the erratum.] Most theories of decision making suggest that, when options imply tradeoffs between their attributes, conflict increases as tradeoff size increases, because greater sacrifices are to be incurred in choosing one option instead of another. An alternative view is that conflict decreases as tradeoff size increases, because stronger arguments can be made for any decision. The authors propose a unified model, the double-mediation model, which combines the mediating effects of sacrifice and argumentation. Our model generally predicts an inverse U-shaped relation between tradeoff size and conflict. Results support this prediction. Also, when the decision situation increases the mediating effect of sacrifice relative to that of argumentation, the relation between tradeoff size and conflict changes in an upward direction; conversely, when the decision situation increases the mediating effect of argumentation relative to that of sacrifice, the relation changes in a downward direction. Results support these predictions as well. Commonalities and differences between our model and other formulations are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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Adaptive grid refinement is potentially a very powerful means of dealing with singularities and other types of misbehavior in the solutions of elliptic partial differential equations. Combined with the multi-level iterative technique for solving the matrix equations, the method can be implemented in a reasonably efficient fashion. 相似文献
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Explores the impact of physical abnormalities on interpersonal relationships and investigates 1 technique available to the stigmatized to influence that impact. This technique is to indicate that the abnormality may be freely discussed or that it is a forbidden topic. The 60 male undergraduate Ss were introduced to an ostensibly naive student who was in reality a confederate and appeared either as an amputee in a wheelchair or as only slightly crippled. The shocks Ss were induced to administer the confederate were less painful when he was severely than when he was slightly crippled. It was concluded that all stigmata do not have the same interpersonal consequences and that the most marked effects occur for behaviors of which Ss have little awareness. (15 ref.) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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Cadmium sulfide and cadmium selenide/cadmium sulfide nanoparticles stabilized in water with poly(cysteine acrylamide) 总被引:1,自引:0,他引:1
Cysteine acrylamide (N-acryloyl L-cysteine) stabilizes CdS nanoparticles as the particles form in aqueous dispersions. Cysteine acrylamide also exchanges for citrate on the surfaces of CdSe and core/shell CdSe/CdS nanoparticles to provide greater stability. Heating of the nanoparticle dispersions polymerizes the cysteine acrylamide on the surface to form a more efficient polydentate stabilizer. The polymer-coated nanoparticle dispersions are colloidally stable even after removal of low molecular weight solutes by dialysis. Emission quantum yields of the polymer-coated CdSe and CdSe/CdS samples were 0.9% and 2.6%, respectively, after aging of the samples in light. CdSe/CdS coated with poly(cysteine acrylamide) is colloidally stable for at least two years in the dark at 5 degrees C. 相似文献
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24 Ss participated in two experiments in which they were required to pick out, from printed panels containing 16 dials, the dial with a deviating pointer. Two versions of a uniformly-aligned configuration and one version of a symmetrically-aligned configuration were studied. S was required to identify both the "different" dial and the direction of the deviating pointer. It was found that (1) both configurations were equally effective for check reading after extended practice, (2) early in practice symmetrical alignment configurations appear to be more difficult, (3) transfer effects from pointer symmetry to uniform alignment are greater than transfer effects in the other direction. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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