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131.
Derek N. Mueller Author Vitae 《Computers and Composition》2009,26(4):240-250
This article offers a theoretical framework for ‘digital underlife’: the distal and potentially transgressive discursive activities proliferated by emerging technologies. Digital underlife is an adaptation of sociologist Erving Goffman's concept of underlife, which figured centrally in Robert Brooke's well-known study of writing activity in 1988. As emerging digital technologies fray the communicative bounds of traditional sites for teaching and learning, such as the classroom and the conference hall, we are confronted anew with a complex array of possibilities for giving and getting attention. Drawing on the work of Charles Moran and Richard Lanham, this article calls for a more receptive disposition toward the productive dimensions of digital underlife. The article promotes a stance that imagines productive digital underlife to be intrinsic to curricula that combine digital writing activity and rhetorical education, rather than short-selling digital underlife as mere distraction, as an impediment to learning, or worse, attempting to banish it altogether. 相似文献
132.
Zhisheng Chen Derek Yates James K. Neathery Kunlei Liu 《Chemical Engineering Research and Design》2012
Uncaptured fly ash and/or suspended solids from wet flue gas desulfurization (WFGD) scrubbing solutions are one of several factors that will influence the performance and robustness of carbon dioxide capture systems in coal-fired power plants which will be installed prior to the exhaust stack. In this study, a 100 mm ID packed column scrubber was tested with different concentrations of ash in various chemical solutions to evaluate the influence of solids on the fluid dynamics of the packing material. Data reported here are collected from three solutions including water, 30 wt% MEA (monoethanolamine), and 20 wt% potassium carbonate. The packing selected for this study was a 16 mm polypropylene pall rings. Compressed air was used to simulate flue gas at near ambient temperature and pressure. 相似文献
133.
Extracting complex lesion phenotypes in Zea mays 总被引:1,自引:0,他引:1
Derek Kelly Avimanyou Vatsa Wade Mayham Toni Kazic 《Machine Vision and Applications》2016,27(1):145-156
134.
Iren Valova Derek Beaton Alexandre Buer Daniel MacLean 《Neural computing & applications》2010,19(7):953-966
Initialization of self-organizing maps is typically based on random vectors within the given input space. The implicit problem
with random initialization is the overlap (entanglement) of connections between neurons. In this paper, we present a new method
of initialization based on a set of self-similar curves known as Hilbert curves. Hilbert curves can be scaled in network size
for the number of neurons based on a simple recursive (fractal) technique, implicit in the properties of Hilbert curves. We
have shown that when using Hilbert curve vector (HCV) initialization in both classical SOM algorithm and in a parallel-growing
algorithm (ParaSOM), the neural network reaches better coverage and faster organization. 相似文献
135.
The distributed control of multi-robot systems has been shown to have advantages over that of conventional single-robot systems. These include scalability, flexibility and robustness to failures. This paper considers pattern formation and reconfigurability in a multi-robot system using a new control algorithm developed through bifurcating potential fields. It is shown how various patterns can be achieved autonomously through a simple free parameter change, with the stability of the system proven to ensure that desired behaviours always occur. 相似文献
136.
Morrison Glenn E.; Wen Joseph Y. M.; Runciman Susan; van der Kooy Derek 《Canadian Metallurgical Quarterly》1999,113(2):358
The C. elegans mutants, lrn-1 and lrn-2, are impaired in associative learning using conditioned taste cues. Both mutants are defective in associative learning about appetitive and aversive events, indicating that lrn-1 and lrn-2 exert effects across motivational boundaries. In a new olfactory associative learning paradigm, in which wild type worms learn to avoid a previously attractive diacetyl odor after it has been paired with an aversive acetic acid solution, lrn-1 and lrn-2 are impaired. Although defective in associative learning using a conditioned olfactory cue, nonassociative learning (habituation and dishabituation) using this same olfactory cue is unaffected. The discovery that lrn-1 and lrn-2 are defective in associative learning with both taste and olfactory cues may suggest that associative learning in different sensory modalities converges on a common genetic pathway in C. elegans that is subserved by lrn-1 and lrn-2. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
137.
Wayne D Cook Fei Chen Derek W Pattison Peyton Hopson Mathieu Beaujon 《Polymer International》2007,56(12):1572-1579
The thermal polymerization of a tetrafunctional thiol (PETMP) and divinyl ether (TEGDVE) was monitored by temperature‐ramping differential scanning calorimetry (DSC) and the effects of inhibitor type and concentration, oxygen inhibition and initiator type were studied. The incorporation of inhibitors was required to produce a stable system at room temperature. Butylated hydroxytoluene (BHT) inhibited polymerization at low temperatures, but was inefficient at high temperatures and polymerization rates, and hence BHT is an ideal stabilizer. In contrast, a nitroxide inhibitor (NO‐67) was a very effective inhibitor and no polymerization occurred until all of the nitroxide was depleted. The presence of oxygen retarded the onset of polymerization but did not change the final conversion significantly. Polymerization with initiators having higher half‐life temperatures shifted the DSC peak to higher temperature because the rate of initiator decomposition and thus initiation was slower. Rheological investigations of the cure at different temperatures revealed that the gel time decreased significantly with increasing cure temperature, and the calculated apparent activation energy for PETMP/TEGDVE was 54 kJ mol?1. Dynamical mechanical thermal analysis of the cured material was undertaken and frequency‐superposed results revealed that the glass transition region of PETMP/TEGDVE/azobisisobutyronitrile was much narrower than that of free‐radically cured dimethacrylate, but was similar to that of an epoxy resin cured with an aromatic diamine. This behaviour could be attributed to PETMP/TEGDVE network homogeneity, or to the less constrained crosslinks in the PETMP/TEGDVE network. Copyright © 2007 Society of Chemical Industry 相似文献
138.
Terahertz computed tomography has been developed based on coherent THz detection and filtered back projection (FBP) algorithms, which allows the global imaging of the internal structure and extraction of the frequency dependent properties. It offers a promising approach for achieving non-invasive inspection of solid materials. However, with traditional CT techniques, i.e. FBP algorithms, full exposure data are needed for inverting the Radon transform to produce cross sectional images. This remains true even if the region of interest is a small subset of the entire image. For time-domain terahertz measurements, the requirement for full exposure data is impractical due to the slow measurement process. This paper explores time domain reconstruction of terahertz measurements by applying wavelet-based filtered back projection algorithms for recovery of a local area of interest from terahertz measurements within its vicinity, and thus improves the feasibility of using terahertz imaging to detect defects in solid materials and diagnose disease states for clinical practise, to name a few applications. 相似文献
139.
140.
Pronunciation performance under speeded conditions was examined for various kinds of letter strings, including pseudohomophones (e.g., TRAX), their real word counterparts (e.g., TRACKS), and a set of nonword controls (e.g., PRAX). Experiment 1 yielded a pronunciation advantage for the pseudohomophones relative to the controls, which was largest among items having few or no orthographic neighbors. Experiment 2 ruled out an account of the pseudohomophone advantage based on differences between pseudohomophones and controls in initial phonemes. Experiment 3 established the existence of a large frequency effect on pronunciation of the base words themselves. These results suggest that whole word representations in the phonological output lexicon are consulted in the course of assembling a pronunciation and that representations in a phonological output lexicon are insensitive to word frequency. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献