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The sign languages used by deaf communities around the world represent a linguistic challenge that natural-language researchers in AI have only recently begun to take up. This challenge is particularly relevant to research in Machine Translation (MT), as natural sign languages have evolved in deaf communities into efficient modes of gestural communication, which differ from English not only in modality but in grammatical structure, exploiting a higher dimensionality of spatial expression. In this paper we describe Zardoz, an on-going AI research system that tackles the cross-modal MT problem, translating English text into fluid sign language. The paper presents an architectural overview of Zardoz, describing its central blackboard organization, the nature of its interlingual representation, and the major components which interact through this blackboard both to analyze the verbal input and generate the corresponding gestural output in one of a number of sign variants.  相似文献   
3.
Abstract

Methods for making more efficient use of synthetic aperture radar (SAR) imagery are considered. Local standard deviation and autocorrelation texture measures are used to provide information on the spatial variability in the scattering cross-section. Use of these statistics in a window of 180×180m improved classification success rates from 39 to 66 per cent with digitized shuttle imaging radar (S1R-A) data. Multispectral scanner (MSS) achieves 70 per cent success with the same window size and, by combining this with SAR, a 78 per cent success rate is reached.  相似文献   
4.
This work optimizes the application of electrochemical potentiokinetic reactivation (EPR) to assess the degree of sensitization (DOS) of AISI 316L and compares the large-scale and small-scale EPR with the aim of improving the study of the different zones of AISI 316L welded joints by using an electrochemical minicell. The optimized EPR allows to discriminate better than the standardized EPR among different DOS. Small-scale EPR shows greater sensitivity to assess the DOS than large-scale EPR: (i) at lower deformation levels; (ii) for shorter sensitization times; (iii) when localized microstructural regeneration is caused by the combined effect of deformation and subsequent sensitization.  相似文献   
5.
Background and Aims: During wine ageing, a great variety of reactions take place, resulting in an immense variety of products whose structure sometimes remains unknown. The aim of this work is the study of different fragmentation patterns of flavanol‐anthocyanin derivatives formed along the wine ageing; these patterns are useful for elucidating the different structures of these compounds and other new related ones. Methods and Results: Several wines from the Protected Denomination of Origin Rioja have been studied by an analytical method that combines column chromatography and high‐performance liquid chromatography with diode array and mass and tandem mass spectrometric detections. Thirty‐five coloured flavanol‐anthocyanin compounds formed by direct reaction or by acetaldehyde‐mediated condensation have been identified. For direct reaction derivatives, two different fragmentation patterns (one of them not previously reported) have been observed depending on the position of flavanol in the coloured derivative. Several compounds have been identified in aged wines for the first time to the authors' knowledge, like (+)‐gallocatechin‐cyanidin‐3‐glucoside and (+)‐catechin‐cyanidin‐3‐glucoside Conclusions: The developed analytical procedure has allowed the identification of some compounds for the first time, and two different fragmentation patterns have been observed depending on the position of flavanol in the pigment. Significance of the Study: The establishment of different fragmentation patterns allows the structural elucidation of unknown compounds.  相似文献   
6.

ABSTRACT

Over two subsequent seasons, emission of volatile compounds, consumer acceptability and quality parameters were analyzed in “Fuji” apples. In both seasons, apples were harvested at the same maturity stage and stored for 19 or 30 weeks at 1C and 92% relative humidity under an ultralow oxygen (ULO) atmosphere (1% O2 + 1% CO2) or under an ULO atmosphere followed by different periods (2 or 4 weeks) in cold air. The results revealed, for both seasons, that 4 weeks of cold air storage after ULO storage helped to increase the emission of some volatile compounds for both storage period, including characteristic volatile compounds for the variety, and did not have a negative effect on quality parameters. Additionally, the consumer acceptability was superior for those fruits.

PRACTICAL APPLICATIONS

It is well known for various apple varieties that long‐term storage under ULO conditions reduces volatile production resulting in poor flavor and aroma compared with fruits stored in air. Consequently, there is often dissatisfaction among consumers with the flavor of fruits which have been subjected to cold storage. The strategy that is proposed in the present work could be recommended to enhance the aromatic quality of fruit provided by the apple industry and, in consequence, increase its acceptability by consumers.  相似文献   
7.
This paper describes a tool to aid the development of computer vision applications for pixel-level diagnosis. A conceptual framework for constructing pixel processors is described. The proposed tool is based on two domains: one deals with numerical images, named features, and the other deals with symbolic images, named classes. A reduced set of image and operator types is defined. Based on it, an object-oriented language is described. The main objects define features and classes and their associated operators, namely procedures, classifiers, and rules. All system control is goal oriented and is designed to provide symbolic images as results when a request is received from a higher level of the image understanding system. Some knowledge engineering concepts, such as certainty control and instances, are also included.  相似文献   
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9.
Polymers have been identified as replacement materials for metallic liners in composite overwrapped pressure vessels (COPVs) for future space launchers. PEEK, Nylon, and PVDF plastics formed from base powder grades have been permeability tested to determine their susceptibility to the diffusion of helium through flatwise panel cross sections. Permeability, diffusion, and solubility coefficients have been obtained for each material with PVDF and PA11 grades showing the lowest permeability coefficients and hence the best barrier properties to permeation. Crystallinity percentages and internal air void contents in the polymer samples have also been used to assess the differences in permeability between materials with an analysis of void dispersion effects given through X‐ray CT scanning techniques. The measured permeability coefficients have been used to assess the ability of all materials tested to act as a functional polymer liner in a standard COPV with final leak rates predicted based on liner thicknesses and weights. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 43675.  相似文献   
10.
Aluminum alloy samples, 6061-T6 and 2219-T42, were exposed to Caribbean seawater for 90 d. The fluctuations of open circuit potential, considered as electrochemical noise (EN), were used to characterize and compare initial pitting events, which appeared on their surfaces. EN analysis was carried out using the power spectral density (PSD) vs frequency. The decrease of the β exponent in PSD graphs indicated a release of spontaneous energy with the progress of pit formation in seawater. The fluctuations were associated with the breakdown and formation of new corrosion layers. The values of β exponent in PSD graphs suggest that corrosion process of AA2219-T42 alloy occurs as a persistent non-stationary process, the dynamics of which is controlled by fractional Brownian motion (fBm), while on AA6061-T6 alloy the corrosion process was dominated by stationary and weakly persistent features, with the contribution of fractional Gaussian noise (fGn). After the exposure in seawater, SEM-EDX analysis revealed insoluble intermetallic particles on the alloys, rich in Cu or Fe and irregularly distributed. The preferential dissolution of Mg and Al occurs from the S-phase (Al2CuMg) of AA2219-T42 alloy.  相似文献   
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