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1.
ABSTRACT

In April 2006, Alliance Library System and Online Programming for All Libraries partnered to start the Second Life Library 2.0 in the online world Second Life and in August 2006 purchased an island on the Teen grid of Teen Second Life. Second Life is a virtual world, a descendant of multiplayer online games. Educational institutions have recently been drawn into Second Life's robust economy and vibrant cultural life. The Second Life Library 2.0 works with librarians from around the world and with other educational partners such as TechSoup, WorldBridges, and the New Media Consortium. Second Life Library 2.0 provides “traditional” library services such as ready reference, book discussions, and search assistance, but, at heart, it explores what it means to be a virtual library in a virtual world.  相似文献   
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It is common practice in audiovisual archives to disclose documents using metadata from a structured vocabulary or thesaurus. Many of these thesauri have limited or no structure. The objective of this paper is to find out whether retrieval of audiovisual resources from a collection indexed with an in-house thesaurus can be improved by enriching the thesaurus structure. We propose a method to add structure to a thesaurus by anchoring it to an external, semantically richer thesaurus. We investigate the added value of this enrichment for retrieval purposes. We first anchor the thesaurus to an external resource, WordNet. From this anchoring we infer relations between pairs of terms in the thesaurus that were previously unrelated. We employ the enriched thesaurus in a retrieval experiment on a TRECVID 2007 dataset. The results are promising: with simple techniques we are able to enrich a thesaurus in such a way that it adds to retrieval performance.  相似文献   
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A three-dimensional thermohydrodynamic lubrication model which couples the Reynolds and energy equations is developed in the finite-element program Sepran. The model uses the streamline upwind Petrov-Galerkin method. Model results indicate the peak temperature is not on the mid-plane surface. This position shifts toward the mid-plane as the width-to-length ratio is reduced from 10 to 1 as well as when pressure boundary conditions are altered in such a way that the inlet/outlet pressure is higher than the side pressure. The adiabatic temperature profiles of an infinite slider and a square slider are compared. The wider slider shows a higher peak temperature. The side flow plays a major role in determining the value and position of the peak temperature. Model results also indicate peak side flow at a width-to-length ratio of 2.  相似文献   
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In epitaxial thin film systems, the crystal structure and its symmetry deviate from the bulk counterpart due to various mechanisms such as epitaxial strain and interfacial structural coupling, which is accompanyed by a change in their properties. In perovskite materials, the crystal symmetry can be described by rotations of sixfold coordinated transition metal oxygen octahedra, which are found to be altered at interfaces. Here, it is unraveled how the local oxygen octahedral coupling at perovskite heterostructural interfaces strongly influences the domain structure and symmetry of the epitaxial films resulting in design rules to induce various structures in thin films using carefully selected combinations of substrate/buffer/film. Very interestingly it is discovered that these combinations lead to structure changes throughout the full thickness of the film. The results provide a deep insight into understanding the origin of induced structures in a perovskite heterostructure and an intelligent route to achieve unique functional properties.  相似文献   
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A large variety of transport properties have been observed at the interface between the insulating oxides SrTiO3 and LaAlO3 such as insulation, 2D interface metallicity, 3D bulk metallicity, magnetic scattering, and superconductivity. The relation between the structure and the properties of the SrTiO3/LaAlO3 interface can be explained in a meaningful way by taking into account the relative contribution of three structural aspects: oxygen vacancies, structural deformations (including cation disorder), and electronic interface reconstruction. The emerging phase diagram is much richer than for related bulk oxides due to the occurrence of interface electronic reconstruction. The observation of this interface phenomenon is a display of recent advances in thin film deposition and characterization techniques, and provides an extension to the range of exceptional electronic properties of complex oxides.  相似文献   
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Interactions between electrically induced attack and teeth-chattering from 1 electrode and grooming from another were examined in male albino rats. The interaction between electrically induced attacks and deprivation-induced feeding, as well as the effect of food deprivation on attack, was also studied. Results indicate that attack appears to be a dominant response, for it suppressed grooming and feeding at a low level of activation. On the other hand, it was not affected by simultaneously induced grooming or feeding. However, food deprivation decreased the threshold for attack, leaving attack latency, attack form, or bite targets unaffected. Teeth-chattering, suggested to be related to attack and flight, was also a dominant response. Results suggest that interactions between behavioral systems are in favor of the systems that must act acutely on activation in order to survive. Apparently, the regulations governing these interactions are represented in the functional organization of the brain. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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