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21.
Rachel?BawdenEmail authorView authors OrcID profile Chloé?Clavel Frédéric?Landragin 《Language Resources and Evaluation》2016,50(4):821-838
We present a corpus-based prosodic analysis with the aim of uncovering the relationship between dialogue acts, personality and prosody in view to providing guidelines for the ECA Greta’s text-to-speech system. The corpus used is the SEMAINE corpus, featuring four different personalities, further annotated for dialogue acts and prosodic features. In order to show the importance of the choice of dialogue act taxonomy, two different taxonomies were used, the first corresponding to Searle’s taxonomy of speech acts and the second, inspired by Bunt’s DIT++, including a division of directive acts into finer categories. Our results show that finer-grained distinctions are important when choosing a taxonomy. We also show with some preliminary results that the prosodic correlates of dialogue acts are not always as cited in the literature and prove more complex and variable. By studying the realisation of different directive acts, we also observe differences in the communicative strategies of the ECA depending on personality, in view to providing input to a speech system. 相似文献
22.
Despite all the financial resources that are directed to support and acquire learning technologies, the results have been generally disappointing. Faculty are eager to use technology but lack the technical skills, ability, and experience. Library staff includes a talent tool rich in Information and Communication Technologies (ICT)/WEB 2.0 technical expertise and experience. In terms of content sourcing and procurement, library technical services and selection staff have broad knowledge of the marketplace for online information and content as well as experience in licensing access. They have a firm grasp of the transaction process, workflows, pricing, and licensing negotiations. Content development and sourcing inevitably involves access management, online storage, copyright, and licensing—things at which libraries are good. ICT deployment is changing teaching and learning on campuses, and the roles of those involved in teaching and learning are also changing. Whether formally through mandated library services, or informally through back channels, library staff are supporting faculty new technology use as well as faculty teaching materials content sourcing and procurement. 相似文献
23.
Stephen J. Walsh Amy L. McCleary Carlos F. Mena Yang Shao Julie P. Tuttle Augusto Gonzlez Rachel Atkinson 《Remote sensing of environment》2008,112(5):291-1941
In the Galapagos Islands of Ecuador, one of the greatest threats to the terrestrial ecosystem is the increasing number and areal extent of invasive species. Increased human presence on the islands has hastened the introduction of plant and animal species that threaten the native and endemic flora and fauna. Considerable research on invasive species in the Galapagos Islands has been conducted by the Charles Darwin Foundation. We complement that work through a spatially- and spectrally-explicit satellite assessment of an important invasive plant species (Psidium guajava — guava) on Isabela Island that integrates diverse remote sensing systems, data types, spatial and spectral resolutions, and analytical and image processing approaches. QuickBird and Hyperion satellite data are processed to characterize the areal extent and spatial structure of guava through the following approaches: (1) QuickBird data are classified through a traditional pixel-based approach (i.e., an unsupervised classification approach using the ISODATA algorithm), as well as an Object-Based Image Analysis (OBIA) approach; (2) multiple approaches for spectral “unmixing” of the Hyperion hyper-spectral data are assessed to construct spectral end-members from QuickBird data using linear and non-linear mixture modeling approaches; and (3) landscape pattern metrics are calculated and compared for the pixel-based, object-based, and spectral unmixing approaches. The spectral–spatial characteristics of guava are interpreted relative to management strategies for the control of guava and the restoration of natural ecosystems in the Galapagos National Park. 相似文献
24.
Electron tomography (ET) combines electron microscopy and the principles of tomographic imaging in order to reconstruct the three-dimensional structure of complex biological specimens at molecular resolution. Weighted back-projection (WBP) has long been the method of choice since the reconstructions are very fast. It is well known that iterative methods produce better images, but at a very costly time penalty. In this work, it is shown that efficient parallel implementations of iterative methods, based primarily on data decomposition, can speed up such methods to an extent that they become viable alternatives to WBP. Precomputation of the coefficient matrix has also turned out to be important to substantially improve the performance regardless of the number of processors used. Matrix precomputation has made it possible to speed up the block-iterative component averaging (BICAV) algorithm, which has been studied before in the context of computerized tomography (CT) and ET, by a factor of more than 3.7. Component-averaged row projections (CARP) is a recently introduced block-parallel algorithm, which was shown to be a robust method for solving sparse systems arising from partial differential equations. It is shown that this algorithm is also suitable for single-axis ET, and is advantageous over BICAV both in terms of runtime and image quality. The experiments were carried out on several datasets of ET of various sizes, using the blob model for representing the reconstructed object. 相似文献
25.
This study is an empirical investigation of problematic instant messaging (IM) use among university students in Singapore. It adapts Caplan's (2005) theoretical framework of problematic Internet use (PIU) to the context of problematic IM use by linking pre-existing human dispositions to cognitive-behavioral symptoms and negative outcomes of improper IM use. Four new factors—oral communication apprehension, polychronicity, perceived inconvenience of using offline communication means, and trait procrastination—were tested as predictors of problematic IM use. The results provided strong support for Caplan's theoretical framework of PIU and indicated that oral communication apprehension and perceived inconvenience of using offline means were significant predictors of problematic IM use, whereas polychronicity and trait procrastination were not. The implications of these findings are discussed. 相似文献
26.
Rachel Fletcher 《Nexus Network Journal》2009,11(1):105-128
The zodiac is widely known as a band of twelve celestial constellations. It also contains a mathematical model for cosmographic
depiction, based on observations of the sun, moon, and visible planets as they traverse the celestial ecliptic. Here wee consider
the zodiac as a timepiece or calendar; how this system of planets and constellations emerges from elementary geometric patterns;
and how these patterns inform the symbols of the zodiac and frame our world view. 相似文献
27.
Fabrizio Angiulli Rachel Ben-Eliyahu – Zohary Luigi Palopoli 《Artificial Intelligence》2008,172(16-17):1837-1872
Default logics are usually used to describe the regular behavior and normal properties of domain elements. In this paper we suggest, conversely, that the framework of default logics can be exploited for detecting outliers. Outliers are observations expressed by sets of literals that feature unexpected semantical characteristics. These sets of literals are selected among those explicitly embodied in the given knowledge base. Hence, essentially we perceive outlier detection as a knowledge discovery technique. This paper defines the notion of outlier in two related formalisms for specifying defaults: Reiter's default logic and extended disjunctive logic programs. For each of the two formalisms, we show that finding outliers is quite complex. Indeed, we prove that several versions of the outlier detection problem lie over the second level of the polynomial hierarchy. We believe that a thorough complexity analysis, as done here, is a useful preliminary step towards developing effective heuristics and exploring tractable subsets of outlier detection problems. 相似文献
28.
Nhan Dai Thien Tram Jian Xu Devika Mukherjee Antonio Eduardo Obanel Venkatesh Mayandi Vanitha Selvarajan Xiao Zhu Jeanette Teo Veluchamy Amutha Barathi Rajamani Lakshminarayanan Pui Lai Rachel Ee 《Advanced functional materials》2023,33(5):2210858
Bacterial trapping using nanonets is a ubiquitous immune defense mechanism against infectious microbes. These nanonets can entrap microbial cells, effectively arresting their dissemination and rendering them more vulnerable to locally secreted microbicides. Inspired by this evolutionarily conserved anti-infective strategy, a series of 15 to 16 residue-long synthetic β-hairpin peptides is herein constructed with the ability to self-assemble into nanonets in response to the presence of bacteria, enabling spatiotemporal control over microbial killing. Using amyloid-specific K114 assay and confocal microscopy, the membrane components lipoteichoic acid and lipopolysaccharide are shown to play a major role in determining the amyloid-nucleating capacity as triggered by Gram-positive and Gram-negative bacteria respectively. These nanonets displayed both trapping and killing functionalities, hence offering a direct improvement from the trap-only biomimetics in literature. By substituting a single turn residue of the non-amyloidogenic BTT1 peptide, the nanonet-forming BTT1-3A analog is produced with comparable antimicrobial potency. With the same sequence manipulation approach, BTT2-4A analog modified from BTT2 peptide showed improved antimicrobial potency against colistin-resistant clinical isolates. The peptide nanonets also demonstrated robust stability against proteolytic degradation, and promising in vivo efficacy and biosafety profile. Overall, these bacteria-responsive peptide nanonets are promising clinical anti-infective alternatives for circumventing antibiotic resistance. 相似文献
29.
An Investigation of the Relationship Between the Gaussian Process Model Parameters and Surface Area in Three Dimensions 下载免费PDF全文
Rachel T. Silvestrini Anthony C. Silvestrini 《Quality and Reliability Engineering International》2016,32(2):391-402
In this paper, we study the relationship between the fitted parameters in a Gaussian process (kriging) model and the complexity of the resulting response surface. This study is done for models with one response and two input variables. An analytical calculation of surface roughness is used as a measure of the complexity of the response surface fit by the Gaussian process model. Our findings indicate that the size of the fitted model parameters as measured across different fits and data sets do not give indication as to the complexity of the surface. We do, however, show that the magnitude of each of the parameters in a single fitted model gives indication about the amount of variability in the direction of that fitted parameter. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
30.
Rachel Fletcher 《Nexus Network Journal》2011,13(2):487-498
A unique geometric construction known to Thomas Jefferson reveals a rich interplay of root-two geometric elements when applied
to Jefferson’s octagonal plan of Poplar Forest, his eighteenth-century villa retreat. 相似文献