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101.
102.
People often coordinate their actions with sequences that exhibit temporal variability and unfold at multiple periodicities. We compared oscillator- and timekeeper-based accounts of temporal coordination by examining musicians' coordination of rhythmic musical sequences with a metronome that gradually changed rate at the end of a musical phrase (Experiment 1) or at the beginning of a phrase (Experiment 2). The rhythms contained events that occurred at the same periodic rate as the metronome and at half the period. Rate change consisted of a linear increase or decrease in intervals between metronome onsets. Musicians coordinated their performances better with a metronome that decreased than increased in tempo (as predicted by an oscillator model), at both beginnings and ends of musical phrases. Model performance was tested with an oscillator period or timekeeper interval set to the same period as the metronome (1:1 coordination) or half the metronome period (2:1 coordination). Only the oscillator model was able to predict musicians' coordination at both periods. These findings suggest that coordination is based on internal neural oscillations that entrain to external sequences. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
103.
Caroline Danowski Volker Gravemeier Lena Yoshihara Wolfgang A. Wall 《International journal for numerical methods in engineering》2013,95(13):1053-1078
In the present work, a monolithic solution approach for thermo‐structure interaction problems motivated by the challenging application of the behaviour of rocket nozzles is proposed. Structural and thermal fields are independently discretised via finite elements. The resulting system of equations is solved via a monolithic thermo‐structure interaction scheme, which is constructed by a block Gauss–Seidel preconditioner in combination with algebraic multigrid methods. The proposed method is tested for four numerical examples, the second Danilovskaya problem, a simplified rocket nozzle configuration, an internally loaded hollow sphere, and a fully three‐dimensional nozzle configuration of a subscale thrust chamber. Good agreement of the numerical results with results from the literature is observed. Furthermore, it is shown that the monolithic solution algorithm can handle the complete range of the parameter spectrum, whereas partitioned algorithms are limited to a certain parameter range only. Moreover, the monolithic algorithm exhibits improved efficiency and robustness compared to partitioned algorithms. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
104.
Emilie Courcot Francis Rebillat Francis Teyssandier Caroline Louchet-Pouillerie 《Journal of the European Ceramic Society》2010,30(4):905-910
A thermodynamic study was carried out in order to quantify the stability of yttrium silicates under different atmospheres (argon, air, moisture), and to predict their behaviour as an EBC. For this purpose, the partial pressures of gaseous species formed during the reactive vaporization in equilibrium with yttrium silicates were evaluated and compared to those over each oxide taken separately. The partial pressures of silicon and rare earth hydroxides at the equilibrium over rare earth silicates are lower than those over each single oxide. Thus yttrium silicates appear to be sufficiently stable to be promising materials to be used as environmental barrier coatings. 相似文献
105.
Maurício Pinheiro de Oliveira Caroline Reggiani Silva Lilia Müller Guerrini 《Journal of Coatings Technology and Research》2011,8(4):439-447
This study investigates the influence of carboxylic monomers, such as itaconic acid (IA), on the colloidal properties of the
latexes made by semi-continuous emulsion copolymerization of styrene (STy) with n-butyl acrylate (BA). A number of copolymerization runs were carried out with different IA concentrations. The effect of functional
monomer on the overall conversion, the colloidal properties of the latexes, and the distribution of the carboxylic groups
(buried, particle surface and aqueous phase) were examined. The carboxylic groups present in the latexes were analyzed using
conductimetric and potentiometric titrations. The behavior of the IA on the wet scrub resistance of highly pigmented paints
for architectural coatings was examined and correlated with the distribution of the carboxylic groups. The results obtained
showed that the properties of highly pigmented paints are greatly dependent on the amount and distribution of the carboxylic
groups. The carboxylic acid distributed in the aqueous phase has a strong influence on the wet scrub resistance and on the
characteristics of the final products. 相似文献
106.
Caroline Fauquant Valérie Briard‐Bion Nadine Leconte Michel Guichardant Marie‐Caroline Michalski 《European Journal of Lipid Science and Technology》2007,109(12):1167-1173
Native milk fat globules of various mean diameters, ranging from d43 = 2.3 µm to 8.0 µm, were obtained using microfiltration of raw whole milk. After milk fat globule washing, the milk fat globule membrane (MFGM) was separated by manual churning. After total lipid extraction and separation of polar lipids, their phospholipid (PL) and sterol composition was measured using thin‐layer chromatography, methyl ester analyses by gas chromatography, and gas chromatography coupled to mass spectrometry. The main PL species were phosphatidylethanolamine, phosphatidylcholine and sphingomyelin. The respective fatty acid composition of each PL species was measured. Many different minor bioactive sterols were detected in the MFGM, e.g. lanosterol, lathosterol, desmosterol, stigmasterol and β‐sitosterol. No significant differences in the PL and sterol profile were found between MFGM extracted from small and large milk fat globule fractions. 相似文献
107.
Mi-Ryn Seong Gye-Young Lee Dong-Kwon Kim Young-Seok Kim Caroline Sunyong Lee 《Metals and Materials International》2009,15(6):963-966
Recent research has focused on preventing copper oxidation for direct wiring applications. In this study, a novel coating
method was developed for nano-sized copper powders using vapor self-assembled monolayer (VSAM). The surfaces of oxidized and
non-oxidized copper powders were studied to determine whether they can be coated with a vapor form of octanethiol. It was
found that non-oxidized copper powders were successfully coated with the vapor form of octanethiol according to X-ray photoelectron
spectroscopy (XPS) analysis. However, due to the partial coating of self-assembled monolayer (SAM) on a copper surface, a
very small amount of copper oxide was detected when the coating mechanism was verified using Atomic Force Microscopy (AFM).
Overall, the vapor form of octanethiol successfully adhered to the surface of nanosized copper powders, constituting the novel
method of preventing oxidation. A complete coating method for the nano-sized copper powders must be developed in future research. 相似文献
108.
109.
Caroline Henton 《International Journal of Speech Technology》2002,5(2):117-131
Highest quality synthetic voices remain scarce in both parametric synthesis systems and in concatenative ones. Much synthetic speech lacks naturalness, pleasantness and flexibility. While great strides have been made over the past few years in the quality of synthetic speech, there is still much work that needs to be done. Now the major challenges facing developers are how to provide optimal size, performance, extensibility, and flexibility, together with developing improved signal processing techniques. This paper focuses on issues of performance and flexibility against a background containing a brief evolution of speech synthesis; some acoustic, phonetic and linguistic issues; and the merits and demerits of two commonly used synthesis techniques: parametric and concatenative. Shortcomings of both techniques are reviewed. Methodological developments in the variable size, selection and specification of the speech units used in concatenative systems are explored and shown to provide a more positive outlook for more natural, bearable synthetic speech. Differentiating considerations in making and improving concatenative systems are explored and evaluated. Acoustic and sociophonetic criteria are reviewed for the improvement of variable synthetic voices, and a ranking of their relative importance is suggested. Future rewards are weighed against current technical and developmental challenges. The conclusion indicates some of the current and future applications of TTS. 相似文献
110.
Caroline Privault Jacki O’Neill Victor Ciriza Jean-Michel Renders 《Artificial Intelligence and Law》2010,18(4):459-479
This paper describes a tool for assisting lawyers and paralegal teams during document review in eDiscovery. The tool combines
a machine learning technology (CategoriX) and advanced multi-touch interface capable of not only addressing the usual cost,
time and accuracy issues in document review, but also of facilitating the work of the review teams by capitalizing on the
intelligence of the reviewers and enabling collaborative work. 相似文献