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991.
Data visualization is aimed at obtaining a graphic representation of high dimensional information. A data projection over
a lower dimensional space is pursued, looking for some structure on the projections. Among the several data projection based
methods available, the Generative Topographic Mapping (GTM) has become an important probabilistic framework to model data.
The application to document data requires a change in the original (Gaussian) model in order to consider binary or multinomial
variables. There have been several modifications on GTM to consider this kind of data, but the resulting latent projections
are all scattered on the visualization plane. A document visualization method is proposed in this paper, based on a generative
probabilistic model consisting of a mixture of Zero-inflated Poisson distributions. The performance of the method is evaluated
in terms of cluster forming for the latent projections with an index based on Fisher’s classifier, and the topology preservation
capability is measured with the Sammon’s stress error. A comparison with the GTM implementation with Gaussian, multinomial
and Poisson distributions and with a Latent Dirichlet model is presented, observing a greater performance for the proposed
method. A graphic presentation of the projections is also provided, showing the advantage of the developed method in terms
of visualization and class separation. A detailed analysis of some documents projected on the latent representation showed
that most of the documents appearing away from the corresponding cluster could be identified as outliers. 相似文献
992.
Joachim Neumann Josep R. Casas Dušan Macho Javier Ruiz Hidalgo 《Personal and Ubiquitous Computing》2009,13(1):15-23
At the Technical University of Catalonia (UPC), a smart room has been equipped with 85 microphones and 8 cameras. This paper
describes the setup of the sensors, gives an overview of the underlying hardware and software infrastructure and indicates
possibilities for high- and low-level multi-modal interaction. An example of usage of the information collected from the distributed
sensor network is explained in detail: the system supports a group of students that have to solve a lab assignment related
problem.
This work has been partially supported by the European Union, IP 506909 (CHIL) 相似文献
993.
Gloria Urbano María López-Jurado Carlos Aranda Antonio Vilchez Lydia Cabrera Jesus M. Porres & Pilar Aranda 《International Journal of Food Science & Technology》2006,41(6):618-626
The effect of sprouting pea seeds (Pisum sativum, L) for 2, 4 and 6 days, with and without light, on the content of zinc (Zn) and magnesium (Mg) and their nutritive utilisation by growing rats was studied. Soaking of pea seeds prior to germination caused a 49% reduction in Zn content followed by minor losses during germination. The content of Mg decreased by 6% as a result of the soaking process, and by 20–28% during germination. Sprouting for 2 and 4 days improved the bioavailability of Zn and Mg from pea seeds (from 32.2 to 88.6–108.0 μg retained Zn per day, and from 1.64 to 2.97–4.79 mg retained Mg per day in raw and sprouted pea flour diets, respectively), outweighing the reductions in Zn and Mg content because of seed soaking. The presence or absence of light during the germination process did not affect the results. We conclude that sprouting of peas for 4 days was the most effective treatment to improve the bioavailability of Zn and Mg in pea seeds. 相似文献
994.
We are presenting a methodological approach that aims to increase students’ motivation by asking them to develop tasks based on professional settings. In order to meet this objective a collaborative methodology was designed and applied to two multidisciplinary projects: MARKETOUR and ICT-SUSTOUR. Both projects made students face real workplace situations by working collaboratively through the use of a virtual learning environment (VLE) and other information technology (IT) tools at a national and international level. 相似文献
995.
Pilar Flores Pilar Hellín Alfredo Lacasa Alicia López Jose Fenoll 《Journal of the science of food and agriculture》2009,89(14):2364-2371
BACKGROUND: Given the contradictory information available concerning the potential beneficial effects of organic production on food quality, there is a need for studies that determine the real effect of cropping systems on fruit quality. A two‐year farm study was therefore conducted to assess differences in the mineral composition and sensory quality of pepper (Capsicum annuum L. cv. Quito) fruits cultivated in organic (O), low‐input (LI) and soilless (SL) systems. Twenty‐four greenhouses were selected following strict criteria in order to reduce the influence of environmental conditions and accurately and realistically reflect commercial production systems. RESULTS: The soil (O and LI) systems provided higher Ca and Mg concentrations than the SL system. In addition, fruit colour was favourably evaluated in green and red peppers from both soil systems. In contrast, SL fruits showed higher firmness in the green stage (related to higher flesh thickness). All fruit parameters that were affected by the cropping system were also affected by the harvesting time. CONCLUSION: The main differences as regards the mineral composition and sensory attributes of the resulting fruit were observed between the soil (O and LI) and SL systems. The benefits of O peppers with respect to LI fruits could only be described as an absence of pesticide residues. Harvesting time can affect fruit composition and quality to a greater extent than cropping system. Copyright © 2009 Society of Chemical Industry 相似文献
996.
Oscar Martínez‐Alvarez Carmen Gómez‐Guillén Pilar Montero 《International Journal of Food Science & Technology》2008,43(11):2010-2018
Different chemical compounds (kojic acid, cumic acid, phytic acid, sodium metabisulphite, magnesium carbonate, sorbic acid and different protease inhibitors) were used as coadjutants in 4‐hexylresorcinol (4‐HR)‐based melanosis‐inhibiting formulas tested for inhibiting melanosis in pink shrimp (Parapenaeus longirostris). The experiment was performed on board ship. Increasing concentrations of 4‐HR delayed the occurrence of melanosis during storage. However, 4‐HR could not prevent the appearance of a yellow‐greenish colouration in the cephalothorax that diminishes the consumer acceptability of shrimps. The incorporation of protease inhibitors (ethylenediaminetetraacetic acid, disodium dihydrogen pyrophosphate, iodoacetic acid, egg white and phenylmethylsulphonyl fluoride) into the 4‐HR‐based mixtures improved the acceptability after storage, suggesting that protease activity post‐mortem contributes to the reduction in the final acceptability of crustaceans. 相似文献
997.
María C lvarez del Pino Gonzalo Hervs ngel R Mantecn F Javier Girldez Pilar Frutos 《Journal of the science of food and agriculture》2005,85(4):583-590
Tannin contents of stems, flowers and leaves of four shrub species (Erica arborea, Erica australis, Cytisus cantabricus and Genista occidentalis) were chemically assessed using two colorimetric assays (butanol–HCl and Folin–Ciocalteu) and several standards (tannic acid, purified quebracho condensed tannins (CT) and purified CT extracted from each species). A method based on the biological activity of tannins in the rumen was also used for assaying tannins. Depending on the species, the use of quebracho tannin as standard over‐ or underestimated CT contents, in comparison to the use of the respective internal standard. However, the high correlationship observed between in vitro gas production in the presence or absence of polyethylene glycol (PEG) and CT contents estimated from quebracho suggests that this standard could be used for a quicker estimate of the nutritive value of tannin‐containing plants. Tannin contents obtained by the Folin–Ciocalteu method, using tannic acid as standard, were also related to their activity on rumen fermentation. The use of the in vitro gas production technique, in the absence or presence of PEG, may provide more useful information than the chemical assays when the final aim of tannin analysis is to assess the nutritive value of feedstuffs for ruminants. Copyright © 2004 Society of Chemical Industry 相似文献
998.
Daniele Sofia Pilar Coca Llano Aristide Giuliano Mariola Iborra Hernández Francisco García Peña Diego Barletta 《Chemical Engineering Research and Design》2014
Integrated Gasification Combined Cycle plants (IGCC) are efficient power generation systems with low pollutants emissions. Moreover, the entrained flow gasifier of IGCC plants allows the combined use of other lower cost fuels (biomass and waste) together with coal. Co-firing with biomass is beneficial for the reduction of CO2 emissions of fossil source. 相似文献
999.
1000.
The degree of sensitization (DOS) in resistance spot welding (RSW) joints is considered as the combined effect of intergranular corrosion (IGC) and transgranular corrosion (TGC) in the heat affected zone (HAZ) and of interdendritic corrosion (IDC) in the weld nugget (WN). The DOS is evaluated from electrochemical potentiokinetic reactivation (EPR) tests. The application of EPR test to RSW joints is optimized and an electrochemical minicell is used to study the effect of heat input on IDC in the WN. 相似文献