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Abstract

With a growing number of embedded digital experiences in arts and heritage settings, creating a broad global field, this article focuses on the use of mobile phones in the engagement of humans with the cultural heritage of public spaces, specifically those that require a promenade from one outdoor space to another. This article discusses findings from a recent promenade initiative, commissioned for a UK arts festival, along with a review of literature, to critically engage with growing evidence of the diverse ways in which technology is integrated at direct user level. Concepts of ‘hybrid spaces’ and ‘user agency’ are discussed, along with the ‘performativity’ of spaces. Central to the discussion is the function of narrative in engaging the participant to construct new perspectives, which are facilitated by the mediating role of personal media devices between subject, narrative, space and community.  相似文献   
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By virtue of the high-affinity specific interaction between the vitamin, biotin, and the protein, streptavidin, monolayers of synthetic lipids with biotin headgroups can tightly bind streptavidin at the lipid-water interface. Through this specific recognition fluorescently-labelled streptavidin spontaneously organizes in the plane of the interface to form large protein domains, directly visible in situ by fluorescence microscopy and exhibiting optical anisotropy. Further structural characterization has shown that these domains are two-dimensional protein crystals. Correlation with the known three-dimensional crystal structure of streptavidin indicates that two of streptavidin's four biotin binding sites are free for further derivatization to create multilayered organized protein molecular devices.  相似文献   
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The geometric correction of airborne scanner imagery has conventionally been performed in a non-parametric manner using ground control. Parametric geometric correction methods are less reliant on ground control and have potential for automation.Recently the possibility of correcting parametrically airborne scanner imagery has become viable because of advances in the availability and accuracy of devices that may be used to measure the exterior orientation of an airborne platform. This paper describes a study initiated by the U.K. Natural Environment Research Council (NERC) to develop and investigate a provisional parametric correction system. Flight trials were flown at an altitude of 1000 m and exterior orientation parameters measured by an inertial navigation system were used to produce parametrically corrected images. The results of this study demonstrate the feasibility of the parametric correction approach.  相似文献   
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In this review article, the most popular types of neural network control systems are briefly introduced and their main features are reviewed. Neuro control systems are defined as control systems in which at least one artificial neural network (ANN) is directly involved in generating the control command. Initially, neural networks were mostly used to model system dynamics inversely to produce a control command which pushes the system towards a desired or reference value of the output (1989). At the next stage, neural networks were trained to track a reference model, and ANN model reference control appeared (1990). In that method, ANNs were used to extend the application of adaptive reference model control, which was a well‐known control technique. This attitude towards the extension of the application of well‐known control methods using ANNs was followed by the development of ANN model‐predictive (1991), ANN sliding mode (1994) and ANN feedback linearization (1995) techniques. As the first category of neuro controllers, inverse dynamics ANN controllers were frequently used to form a control system together with other controllers, but this attitude faded as other types of ANN control systems were developed. However, recently, this approach has been revived. In the last decade, control system designers started to use ANNs to compensate/cancel undesired or uncertain parts of systems' dynamics to facilitate the use of well‐known conventional control systems. The resultant control system usually includes two or three controllers. In this paper, applications of different ANN control systems are also addressed. Copyright © 2011 John Wiley and Sons Asia Pte Ltd and Chinese Automatic Control Society  相似文献   
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The shikimate pathway presents an attractive target for malaria chemotherapy. Three shikimic acid analogs exhibited different effects on Plasmodium falciparum growth. (6R)-6-Fluoro-shikimate and (6S)-6-fluoro-shikimate inhibited growth (50% inhibitory concentrations, 1.5 x 10(-5) and 2.7 x 10(-4) M, respectively), whereas 2-fluoro-shikimate had no effect. para-Aminobenzoic acid abrogated the inhibition, demonstrating that the shikimate pathway was specifically targeted.  相似文献   
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