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Elaine El‐Khawas 《Tertiary Education and Management》2013,19(1):37-46
Abstract This paper examines the factors that cause universities to undertake academic change, specifically, changes to achieve more effective teaching and learning. Based on an analysis of 30 reform‐oriented US colleges and universities, it suggests that universities respond to diverse environmental pressures, not solely to external mandates. There is evidence, too, that internal forces within universities can be an impetus for change. 相似文献
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Learning theory provides a powerful framework for analyzing instructional consultations and increasing their effectiveness. In this paper, the authors review the main tenets of learning theory, apply them to consultation scenarios, and present a complex case study to show how they can guide analysis and problem solving around challenging consultations. 相似文献
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This article offers productive usability as a usability approach that focuses on the usefulness of civic Web sites. Although some sites meet traditional usability standards, civic sites might fail to support technical literacy, productive inquiry, collaboration, and a multidimensional perspective—all essential ingredients for citizen-initiated change online. In this article, we map productive usability onto broader philosophies of usability and offer a framework for rethinking usability in civic settings and for teaching productive usability. 相似文献
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Lead is commonly used for making small size organ-pipes instead of using tin alloys. In fact, when the organ-pipes are small enough to avoid collapsing due to room temperature creep, lead can be used instead of other alloys with superior mechanical properties, because it is relatively cheap, it is easy to form into different shapes, the tonality of the obtained sounds are acceptable and the corrosion resistance is quite good. However, organic substances such as organic acids released from the wood made support of the organ-pipes and organic contaminations of the air pumped through the pipes may lead to a rapid degradation of lead. In this study, the effect of organic acids, such as acetic acid, on the degradation of lead-made organ-pipes was investigated. Lead made specimens obtained from real organ-pipes were exposed to organic-acid rich environments and the induced degradation was monitored by means of electrochemical techniques. In literature, it was evidenced that the degradation promoted by the organic acids leads to the formation of lead oxides and carbonates characterized by a very high volume, which promotes a quick degradation of the lead specimens. The effect of different concentrations of acetic acid on the degradation rate of the organ pipes was investigated by means of electrochemical impedance spectroscopy (EIS). The effect of the acid concentration on the corrosion process occurring on lead surface was evaluated by means of cathodic and anodic polarization measurements in both aerated and degassed conditions. The morphology of the degradation products was investigated by means of SEM during exposure time in the aggressive environment. 相似文献
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Mohamad Sleiman Rachid Bouyekhf Adbellah El Moudni 《Journal of The Franklin Institute》2019,356(1):351-381
The paper explores the application of thermodynamic formalism to model and control transportation networks. Specifically, by considering the vehicles as the abstract energy supplied to the system, we show in certain circumstances that certain thermodynamic concepts such as temperature, thermal capacity and thermal equilibrium can have the corresponding notions in transportation context. In addition, despite the lack of a natural principle in transportation context that corresponds to the second law of thermodynamic as we will show, the most important thermodynamic notion, which is the entropy, can be also defined in order to measure the disorder of transportation systems. It is then shown that the state when all lanes have the same occupancy corresponds to the thermal equilibrium arising in isolated thermodynamic system. This equilibrium occupancy leads to a minimum entropy corresponding to a minimal disorder. Besides, by taking the transportation entropy as the storage function, a robust dissipativity based control strategy is presented to reduce the disorder and render the system better organized. Finally, an example is worked out to illustrate the results. 相似文献
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