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991.
Angela Tinwell Mark GrimshawDebbie Abdel Nabi Andrew Williams 《Computers in human behavior》2011,27(2):741-749
With technology allowing for increased realism in video games, realistic, human-like characters risk falling into the Uncanny Valley. The Uncanny Valley phenomenon implies that virtual characters approaching full human-likeness will evoke a negative reaction from the viewer, due to aspects of the character’s appearance and behavior differing from the human norm. This study investigates if “uncanniness” is increased for a character with a perceived lack of facial expression in the upper parts of the face. More important, our study also investigates if the magnitude of this increased uncanniness varies depending on which emotion is being communicated. Individual parameters for each facial muscle in a 3D model were controlled for the six emotions: anger, disgust, fear, happiness, sadness and surprise in addition to a neutral expression. The results indicate that even fully and expertly animated characters are rated as more uncanny than humans and that, in virtual characters, a lack of facial expression in the upper parts of the face during speech exaggerates the uncanny by inhibiting effective communication of the perceived emotion, significantly so for fear, sadness, disgust, and surprise but not for anger and happiness. Based on our results, we consider the implications for virtual character design. 相似文献
992.
Angela Bonifati Werner Nutt Riccardo Torlone Jan Van den Bussche 《The VLDB Journal The International Journal on Very Large Data Bases》2016,25(3):381-397
Conjunctive database queries have been extended with a mechanism for object creation to capture important applications such as data exchange, data integration, and ontology-based data access. Object creation generates new object identifiers in the result that do not belong to the set of constants in the source database. The new object identifiers can be also seen as Skolem terms. Hence, object-creating conjunctive queries can also be regarded as restricted second-order tuple-generating dependencies (SO-tgds), considered in the data exchange literature. In this paper, we focus on the class of single-function object-creating conjunctive queries, or sifo CQs for short. The single-function symbol can be used only once in the head of the query. We give a new characterization for oid-equivalence of sifo CQs that is simpler than the one given by Hull and Yoshikawa and places the problem in the complexity class NP. Our characterization is based on Cohen’s equivalence notions for conjunctive queries with multiplicities. We also solve the logical entailment problem for sifo CQs, showing that also this problem belongs to NP. Results by Pichler et al. have shown that logical equivalence for more general classes of SO-tgds is either undecidable or decidable with as yet unknown complexity upper bounds. 相似文献
993.
In recent years, real‐time 3D scanning technology has developed significantly and is now able to capture large environments with considerable accuracy. Unfortunately, the reconstructed geometry still suffers from incompleteness, due to occlusions and lack of view coverage, resulting in unsatisfactory reconstructions. In order to overcome these fundamental physical limitations, we present a novel reconstruction approach based on retrieving objects from a 3D shape database while scanning an environment in real‐time. With this approach, we are able to replace scanned RGB‐D data with complete, hand‐modeled objects from shape databases. We align and scale retrieved models to the input data to obtain a high‐quality virtual representation of the real‐world environment that is quite faithful to the original geometry. In contrast to previous methods, we are able to retrieve objects in cluttered and noisy scenes even when the database contains only similar models, but no exact matches. In addition, we put a strong focus on object retrieval in an interactive scanning context — our algorithm runs directly on 3D scanning data structures, and is able to query databases of thousands of models in an online fashion during scanning. 相似文献
994.
995.
Johannes Pittermann Angela Pittermann Wolfgang Minker 《International Journal of Speech Technology》2010,13(1):49-60
The involvement of emotional states in intelligent spoken human-computer interfaces has evolved to a recent field of research.
In this article we describe the enhancements and optimizations of a speech-based emotion recognizer jointly operating with
automatic speech recognition. We argue that the knowledge about the textual content of an utterance can improve the recognition
of the emotional content. Having outlined the experimental setup we present results and demonstrate the capability of a post-processing
algorithm combining multiple speech-emotion recognizers. For the dialogue management we propose a stochastic approach comprising
a dialogue model and an emotional model interfering with each other in a combined dialogue-emotion model. These models are
trained from dialogue corpora and being assigned different weighting factors they determine the course of the dialogue. 相似文献
996.
William C. Records Shuya Wei Angela M. Belcher 《Small (Weinheim an der Bergstrasse, Germany)》2019,15(44)
Transition metal phosphides are a new class of materials generating interest as alternative negative electrodes in lithium‐ion batteries. However, metal phosphide syntheses remain underdeveloped in terms of simultaneous control over phase composition and 3D nanostructure. Herein, M13 bacteriophage is employed as a biological scaffold to develop 3D nickel phosphide nanofoams with control over a range of phase compositions and structural elements. Virus‐templated Ni5P4 nanofoams are then integrated as thin‐film negative electrodes in lithium‐ion microbatteries, demonstrating a discharge capacity of 677 mAh g–1 (677 mAh cm–3) and an 80% capacity retention over more than 100 cycles. This strong electrochemical performance is attributed to the virus‐templated, nanostructured morphology, which remains electronically conductive throughout cycling, thereby sidestepping the need for conductive additives. When accounting for the mass of additional binder materials, virus‐templated Ni5P4 nanofoams demonstrate the highest practical capacity reported thus far for Ni5P4 electrodes. Looking forward, this synthesis method is generalizable and can enable precise control over the 3D nanostructure and phase composition in other metal phosphides, such as cobalt and copper. 相似文献
997.
Bao-Nguyen T. Nguyen Angela B. Grommet Arnaud Tron Maureen C. A. Georges Jonathan R. Nitschke 《Advanced materials (Deerfield Beach, Fla.)》2020,32(19):1907241
The directed motion of species against a chemical potential gradient is a fundamental feature of living systems, underpinning processes that range from transport through cell membranes to neurotransmission. The development of artificial active cargo transport could enable new modes of chemical purification and pumping. Here, a heat engine is described that drives chemical cargo between liquid phases to generate a concentration gradient. The heat engine, composed of a functionalized FeII4L4 coordination cage, is grafted with oligoethylene glycol imidazolium chains. These chains undergo a conformational change upon heating, causing the cage and its cargo to reversibly transfer between aqueous and organic phases. Furthermore, sectional heating and cooling allow for the cage to traverse multiple phase boundaries, allowing for longer-distance transport than would be possible using a single pair of phases. 相似文献
998.
XML path summaries are compact structures representing all the simple parent-child paths of an XML document. Such paths have
also been used in many works as a basis for partitioning the document’s content in a persistent store, under the form of path
indices or path tables. We revisit the notions of path summaries and path-driven storage model in the context of current-day
XML databases. This context is characterized by complex queries, typically expressed in an XQuery subset, and by the presence
of efficient encoding techniques such as structural node identifiers. We review a path summary’s many uses for query optimization,
and given them a common basis, namely relevant paths. We discuss summary-based tree pattern minimization and present some efficient summary-based minimization heuristics. We
consider relevant path computation and provide a time- and memory-efficient computation algorithm. We combine the principle
of path partitioning with the presence of structural identifiers in a simple path-partitioned storage model, which allows
for selective data access and efficient query plans. This model improves the efficiency of twig query processing up to two
orders of magnitude over the similar tag-partitioned indexing model. We have implemented the path-partitioned storage model
and path summaries in the XQueC compressed database prototype [8]. We present an experimental evaluation of a path summary’s practical feasibility and of tree pattern matching in a path-partitioned
store. 相似文献
999.
Active rules for XML: A new paradigm for E-services 总被引:1,自引:0,他引:1
Angela Bonifati Stefano Ceri Stefano Paraboschi 《The VLDB Journal The International Journal on Very Large Data Bases》2001,10(1):39-47
XML is rapidly becoming one of the most widely adopted technologies for information exchange and representation. As the use
of XML becomes more widespread, we foresee the development of active XML rules, i.e., rules explicitly designed for the management
of XML information. In particular, we argue that active rules for XML offer a natural paradigm for the rapid development of
innovative e-services. In the paper, we show how active rules can be specified in the context of XSLT, a pattern-based language
for publishing XML documents (promoted by the W3C) which is receiving strong commercial support, and Lorel, a query language
for XML documents that is quite popular in the research world. We demonstrate, through simple examples of active rules for
XSLT and Lorel, that active rules can be effective for the implementation of e-commerce services. We also discuss the various
issues that need to be considered in adapting the notion of relational triggers to the XML context.
Received: 30 October 2000 / Accepted: 19 December 2000 Published online: 27 April 2001 相似文献
1000.
Sorgoleone from root exudate inhibits mitochondrial functions 总被引:4,自引:0,他引:4
James A. Rasmussen Angela M. Hejl Frank A. Einhellig John A. Thomas 《Journal of chemical ecology》1992,18(2):197-207
The aim of this investigation was to determine if sorgoleone (SGL), a hydrophobic compound inSorghum bicolor (L.) Moench root exudate, interferes with mitochondrial functions. Tests were conducted on mitochondria isolated from etiolated soybean [Glycine max (L.) Merr.] and corn (Zea mays L.) seedlings. The data show SGL is a potent inhibitor of state 3 and state 4 respiration rates in both soybean and corn. Using either NADH, succinate, or malate as substrate, the I50 was about 0.5M SGL for state 3 and 5.0M for state 4 based on 0.3–0.5 mg mitochondrial protein. Absorption spectra indicate SGL blocks electron transport at theb-c
1 complex. These data show that disruption of mitochondrial function may be a mechanism of SGL-mediated growth inhibition previously reported and demonstrate a probable role of SGL inSorghum allelopathy.This study was supported in part by National Science Foundation grant RII-8902066 (South Dakota EPSCOR). 相似文献