A leitura como um processo cognitivo
Figueiredo, Olívia Maria
1999-01-01
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Tourism product descriptions are strongly supported on natural language expressions. Appropriate offer selection, according to tourist needs, depends highly on how these are communicated. Since no human interaction is available while presenting tourism products online, the way these are presented, even when using only textual information, is a key success factor for tourism web sites to achieve a purchase. Due to the large amount of tourism offers and the high dynamics in this sector, manual data management is not a reliable or a scalable solution. This paper presents a prototype developed for automatic extraction of relevant knowledge from tourism-related natural language texts. Captured knowledge is represented in a normalized format and new textual descriptions are produced according to available marketing channels. At this phase, t...
Anthocyanins have gathered the attention of the scientific community mostly due to their vast
range of possible applications. They have been the center point of the research in many different
fields, among which is food development, where their innate coloring, antioxidant capacity and
biological potential open interesting venues to the development of new food additives and
functional foodstuffs. As the range of application grows, so does the necessity to obtain these
compounds and since they are naturally occurring, the most common way to obtain anthocyanins
is to extract them from different plant sources, such as fruits and flowers. Several efforts have
been made to develop methods that allow for better extraction yields and higher purification rates
therefore this review aims to compile the information regarding extraction a...
This paper presents a parallel corpora-based bilingual terminology extraction method based on the occurrence of bilingual morphosyntactic patterns in probabilistic translation dictionaries. We discuss an experiment focused on two language pairs – English-Galician and English-Portuguese, and show results which experimentally confirm the high degree of accuracy of the proposed extraction technique.
Parallel corpora are rich sources of translation resources. This document presents a methodology for the extraction of bilingual nominals (terminology candidates) from parallel corpora, using translation patterns. The patterns proposed in this work specify the order changes that occur during translation and that are intrinsic to the involved languages syntaxes. These patterns are described in a domain specific language named PDL (Pattern Description Language), and are extremely efficient for the detection of nominal phrases.
Hyperspectral instruments have been incorporated in satellite missions, providing data of high spectral resolution of the Earth. This data can be used in remote sensing applications, such as, target detection, hazard prevention, and monitoring oil spills, among others. In most of these applications, one of the requirements of paramount importance is the ability to give real-time or near real-time response. Recently, onboard processing systems have emerged, in order to overcome the huge amount of data to transfer from the satellite to the ground station, and thus, avoiding delays between hyperspectral image acquisition and its interpretation. For this purpose, compact reconfigurable hardware modules, such as field programmable gate arrays (FPGAs) are widely used.
This paper proposes a parallel FPGA-based architecture for endmember’s si...
Phenolic compounds are very important to the physiology of plants as well as humans because once ingested they have a protective role on the human body against oxidative stress, acting as antioxidants. Phenolic compounds have thousands of different structures and they are classified into families according to some characteristics.
The evaluation of phenolic compounds is crucial and the methodologies used either for their extraction from the source materials or for their quantification are much variable and have great influence on the results. Hence, this chapter aims to introduce briefly some knowledge about phenolic compounds and the different categories, then to review some important aspects about the extraction methodologies reported in literature and the methods of analysis, namely the spectrophotometric technics, the chromatograp...
The main objective of this research is to exploit the possibility of using an ex situ solvent extraction technique for the remediation of
soils contaminated with semi-volatile petroleum hydrocarbons. The composition of the organic phase was chosen in order to form a single
phase mixture with an aqueous phase and simultaneously not being disturbed (forming stable emulsions) by the soil particles hauling the
contaminants. It should also permit a regeneration of the organic solvent phase.
As first, we studied the miscibility domain of the chosen ternary systems constituted by ethyl acetate–acetone–water. This system proved
to satisfy the previous requirements allowing for the formation of a single liquid phase mixture within a large spectrum of compositions, and
also allowing for an intimate contact with the soil.
Contaminants in t...
Nordihydroguaiaretic acid (NDGA) is a powerful
antioxidant with biological activities of great
interest in several health areas, including antiviral,
cancer chemopreventive, and antitumorgenic.
Little information is available on extraction
methods of NDGA from Larrea tridentata. Hence,
the aim of this study was to develop a rapid and
effective microwave-assisted extraction (MAE)
method for NDGA recovery from Larrea
tridentata leaves, and to compare the results
obtained with those found using conventional heatreflux
extraction (HRE).
Supercritical fluid extraction of all-E-lycopene from tomato industrial wastes (mixture of skins and seeds) was carried out in a semi-continuous flow apparatus using ethane as supercritical solvent. The effect of pressure, temperature, feed particle size, solvent superficial velocity and matrix initial composition was evaluated. Moreover, the yield of the extraction was compared with that obtained with other supercritical solvents (supercritical CO2 and a near critical mixture of ethane and propane). The recovery of all-E-lycopene increased with pressure, decreased with the increase of the particle size in the initial stages of the extraction and was not practically affected by the solvent superficial velocity. The effect of the temperature was more complex. When the temperature increased from 40 to 60 °C the recovery of all-E-lycopene...
Corn cob samples were treated with water (autohydrolysis reaction) using a liquid to solid
ratio of 10:1 w/w. The optimal condition for extraction of hemicelluloses was found at 185ºC
for 30 min. This resulted in the release of 9.7% of hemicelluloses (% dry starting material),
corresponding to the dissolution of 27.9% of the original hemicellulose. Chemical
composition and physico-chemical properties of the samples were elucidated by a
combination of sugar analyses and thermal analysis. The results showed that the treatment
was effective on the extraction of hemicelluloses from corn cob and that the TGA analysis of
xylan from birch wood was found to be initially degraded at about 220 ºC whereas
hemicelluloses from corn cob would be degraded at about 225 ºC.
