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11.
Traditional distinctions between work/play and classroom/gamespace create barriers to computer games’ integration into academic settings and the writing classroom in particular. For a writing class, the work/play distinction often relegates games to an object of analysis in which students critique the games but have little invested in the gameplay itself. After examining briefly how historical changes in education created these distinctions, we offer an alternative position that places play and gamespace within the realm of the classroom. In so doing, we open up a gap for computer game theory to inform the pedagogy that can be practiced in a writing classroom. We show one such example of game theory informing writing pedagogy—the theory of emergent gaming. We then offer an example of an enacted emergent pedagogy in which students play the massively multiplayer online role-playing game World of Warcraft throughout the term, composing self-determined, rhetorically focused writing projects informed by play and written for other game players.  相似文献   
12.
Virtually every study that has used transmission electron microscopy (TEM) to estimate viral diversity has acknowledged that loss of phage tails during sample preparation may have biased the results. However, the magnitude of this potential bias has yet to be constrained. To characterize biases in virus morphological diversity due to tail loss, six phage strains representing the order Caudovirales were inoculated into sterile sediments and soils. Phage particles were then extracted using standard methods. Morphologies of extracted phage particles were compared to those of unmanipulated control samples to determine the extent of tail breakage incurred by extraction procedures. Podoviruses exhibited the smallest frequency of tail loss during extraction (1.2-14%), myoviruses were moderately susceptible to tail breakage (15-40%), and siphoviruses were highly susceptible (32-76%). Thus, TEM assessments of viral diversity in soils or sediments by distribution of tail morphologies may be biased toward podoviruses and virions lacking tails, while simultaneously underestimating the abundance of siphoviruses. However, since the majority of viral capsids observed under TEM were intact, estimates of viral diversity based on the distribution of capsid diameters may provide a more reliable basis for morphological comparisons within and across ecosystems.  相似文献   
13.
Concrete bridges were built originally to have a cost-effective maintenance free life of 120 years, however both in Europe and the USA this has proved to the totally optimistic. Concrete bridges require major maintenance after twenty to thirty years in order to extend their life The Acoustic Emission technique has been successfully applied to monitor and provide information on the safety of concrete bridges, but the processing of the AE data is often not trivial. This paper proposes a method of AE analysis to assess concrete bridges based on the fact that the AE energy is one of the effective parameters to evaluate the damage of a concrete structure. Results from experiments on concrete beams with different design and loading configurations are presented. It is argued that in some cases the state of damage of bridge beams can be estimated from the AE energy analysis when approximately 45% of the ultimate load has been applied.  相似文献   
14.
There are persistent calls across policy, industry and academia for urban water transitions in order to deliver increased sustainability, liveability and resilience. However, realisation of such transformational change is difficult, and there are a number of undesirable or unsuccessful transition trajectories that can manifest. Drawing on a contemporary stormwater quality management transition in South-East Queensland, Australia, this qualitative research paper provides an empirical exploration of a transition in struggle. The paper examines why and how this transition trajectory unfolded, focusing specifically on the evolution of culture, structure and practice changes from the 1970s to the present-day. The paper makes two scholarly contributions, firstly confirming the dynamic nature of transformational change and indicating the need to design transition initiatives across the culture, structure and practice domains to co-evolve and thereby build a robust and mutually reinforcing transition foundation. The results also reveal the critical role of regulation in providing a safety net for the transition and enabling continued progress even when commitment to policy goals wavers. These results also provide practical insight for practitioners engaged in the implementation of transition processes, and reveal the need for transition advocates to deliberately and proactively engage with regulatory frameworks to embed a novel practice.  相似文献   
15.
Design wind loads are partly based on extreme value analyses of historical wind data, and limitations on the quantity and spatial resolution of wind data pose a significant challenge in such analyses. A promising source of recent wind speed and direction data is the automated surface observing system (ASOS), a network of about 1000 standardized US weather stations. To facilitate the use of ASOS data for structural engineering purposes, procedures and software are presented for (a) extraction of peak gust wind data and thunderstorm observations from archived ASOS reports, (b) classification of wind data as thunderstorm or non-thunderstorm to enable separate analyses, and (c) construction of data sets separated by specified minimum time intervals to ensure statistical independence. The procedures are illustrated using approximately 20-year datasets from three ASOS stations near New York City. It is shown that for these stations thunderstorm wind speeds dominate the extreme wind climate at long return periods. Also presented are estimates based on commingled data sets (i.e., sets containing, indiscriminately, both non-thunderstorm and thunderstorm wind speeds), which until now have been used almost exclusively for extreme wind speed estimates in the US. Analyses at additional stations will be needed to check whether these results are typical for locations with both thunderstorm and non-thunderstorm winds.  相似文献   
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GeS2-CdSe superlattices and composite films are prepared by consecutive thermal evaporation of CdSe and GeS2 in vacuum. CdSe layer thickness varies between 1 and 10 nm, while the thickness of GeS2 layers is either equal (in superlattices) to or 20 times greater (in composite films) than that of CdSe layers. Standard spectral photocurrent measurements and various constant photocurrent methods are used to study optical absorption of all samples. An overall blueshift is observed with decreasing CdSe layer thickness of superlattices. This shift is related to a size-induced increase of the optical band gap of CdSe due to one-dimensional carrier confinement in the continuous nanocrystalline CdSe layers. A number of features are observed in the absorption spectra of composite films containing CdSe nanocrystals with average radii of approximately 2.5 and approximately 3.3 nm. They are discussed in terms of three-dimensional carrier confinement and are considered a manifestation of excited electron states in CdSe nanocrystals embedded in GeS2 thin film matrix. In addition to these discrete features, the exponential dependence of the optical absorption (Urbach) edge indicates a distribution of "valence band" tail states associated with disorder. Transient photoconductivity measurements made on similarly prepared SiOx-CdSe superlattices exhibit a rapid fall in photocurrent by a power law decay over several orders of magnitude of time, which is consistent with multi-pletrapping transport via an extensive distribution of deep defects.  相似文献   
19.
鄂黄长江大桥主桥施工阶段横向应力研究   总被引:1,自引:0,他引:1  
通过模拟鄂黄长江公路大桥主桥梁段悬浇施工过程,建立梁段有限元各阶段应力分析模型,探讨不同施工阶段梁段横向应力增长规律,并将几种横梁预应力筋施工方案作分析比较,提出合理的预应力筋张拉次序.  相似文献   
20.
The relevance of attachment theory and research for practice has become increasingly clear. The authors describe a series of studies with 3 aims: (a) to validate measures of attachment for use by clinicians with adolescents and adults, (b) to examine the relation between attachment and personality pathology, and (c) to ascertain whether factor analysis can recover dimensions of attachment reflecting both interpersonal and narrative style. In 3 studies, experienced clinicians provided psychometric data using 1 of 4 attachment questionnaires (2 adolescent and 2 adult samples). Attachment dimensions predicted both personality pathology and developmental experiences in predictable ways. Factor analysis identified 4 dimensions that replicated across adolescent and adult samples on the basis of a combination of interpersonal and narrative indicators: secure, dismissing, preoccupied, and incoherent/disorganized. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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