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1.
User simulation in a stochastic dialog system 总被引:1,自引:1,他引:0
We present a new methodology of user simulation applied to the evaluation and refinement of stochastic dialog systems. Common weaknesses of these systems are the scarceness of the training corpus and the cost of an evaluation made by real users. We have considered the user simulation technique as an alternative way of testing and improving our dialog system. We have developed a new dialog manager that plays the role of the user. This user dialog manager incorporates several knowledge sources, combining statistical and heuristic information in order to define its dialog strategy. Once the user simulator is integrated into the dialog system, it is possible to enhance the dialog models by an automatic strategy learning. We have performed an extensive evaluation, achieving a slight but clear improvement of the dialog system. 相似文献
2.
Ana Belén Bautista-Ortín Rim Ben Abdallah Liliana del Rocío Castro-López María Dolores Jiménez-Martínez Encarna Gómez-Plaza 《International journal of molecular sciences》2016,17(1)
The transference and reactivity of proanthocyanidins is an important issue that affects the technological processing of some fruits, such as grapes and apples. These processes are affected by proanthocyanidins bound to cell wall polysaccharides, which are present in high concentrations during the processing of the fruits. Therefore, the effective extraction of proanthocyanidins from fruits to their juices or derived products will depend on the ability to manage these associations, and, in this respect, enzymes that degrade these polysaccharides could play an important role. The main objective of this work was to test the role of pure hydrolytic enzymes (polygalacturonase and cellulose) and a commercial enzyme containing these two activities on the extent of proanthocyanidin-cell wall interactions. The results showed that the modification promoted by enzymes reduced the amount of proanthocyanidins adsorbed to cell walls since they contributed to the degradation and release of the cell wall polysaccharides, which diffused into the model solution. Some of these released polysaccharides also presented some reactivity towards the proanthocyanidins present in a model solution. 相似文献
3.
Ana B. Bautista‐Ortín Naiara Busse‐Valverde Jose M. López‐Roca Rocío Gil‐Muñoz Encarna Gómez‐Plaza 《International Journal of Food Science & Technology》2014,49(1):34-41
Winemakers are interested in wines with low bitterness and astringency, and therefore, there is a preference for a higher presence of skin proanthocyanidins in wines. However, the information regarding the effect of reducing or eliminating seed proanthocyanidins from the must or fermenting wine on the characteristics of finished wines is scarce. For this reason, we elaborated a wine using Monastrell grapes from which the seeds had been removed and compared it with a control wine (CW) made from intact grapes. The anthocyanin and proanthocyanidin concentration and profile, and the chromatic and sensory characteristics were studied. The absence of seed proanthocyanidins did not affect anthocyanin concentration, although the proanthocyanidin concentration was 40% lower than in the CW. The copigmentation (CA) study showed that both wines had a similar extent of CA phenomena although colour intensity was higher when seed proanthocyanidins were present. The panellist evaluated the wines elaborated without seeds as being fruitier, less astringent and with an overall higher quality. 相似文献
4.
Deficit irrigation strategies enhance health‐promoting compounds through the intensification of specific enzymes in early peaches 下载免费PDF全文
5.
Alberto León Encarna Durán C. Benedito de Barber 《Zeitschrift für Lebensmitteluntersuchung und -Forschung A》1997,205(2):131-134
The effect of dextrins produced by α-amylase on the firming and amylopectin retrogradation of wheat starch gels was studied.
Different gel samples were prepared and included several ingredients, for example, α-amylase, vital gluten and glucoamylase.
Amylopectin retrogradation, gel firming and the dextrin profile were analysed throughout a 5-day storage period. Both processes,
i.e. firming and starch retrogradation, increased with time, and were not affected by the incorporation of gluten into the
mixture. The well-known effect of α-amylase to retard bread crumb firming was also found to be relevant to starch gels. From
the results obtained in this work, it seems that this anti-firming effect is not due to modifications of the starch but to
dextrins produced by starch hydrolysis, since the effect did not occur when dextrins were removed by glucoamylase.
Received: 30 December 1996 相似文献
6.
Patrícia Valentão Rosa M. Seabra Graciliana Lopes Luís R. Silva Vitor Martins Martha E. Trujillo Encarna Velázquez Paula B. Andrade 《Food chemistry》2007,100(1):64-70
The anthocyanin, organic acid and volatile phenol compositions of red wine obtained from Touriga Nacional grapes growing in the Dão region (Portugal) were determined by HPLC/DAD, HPLC/UV and GC/FID, respectively. By these means, nine anthocyanic compounds (malvidin-3,5-O-diglucoside, cyanidin-3-O-galactoside, cyanidin-3-O-glucoside, peonidin-3-O-glucoside, malvidin-3-O-glucoside, delphinidin, cyanidin, pelargonidin and malvidin), six organic acids (ketoglutaric, tartaric, malic, quinic, lactic and shikimic acids) and two volatile phenols (4-ethylguaiacol and 4-ethylphenol) were identified and quantified. Malvidin-3-O-glucoside, the pair lactic plus shikimic acids and 4-ethylguaiacol were the main anthocyanin, organic acids and volatile phenol, respectively. The effects of nine different Dekkera bruxellensis strains on these chemical parameters were also evaluated. The results obtained indicate that some strains of D. bruxellensis yeast are able to cause deterioration of red wine from the Dão region during its maturation by the production of volatile phenols, namely 4-ethylphenol. 相似文献
7.
8.
Szenario 2005 . Um sich auf dem Bildungsmarkt behaupten zu k?nnen, müssen Universit?ten und Fachhochschulen ihre St?rken herausstellen und
sich auf die neue Konkurrenz vorbereiten, fordert die Schrift, die von dem Expertenkreis „Hochschulentwicklung durch neue
Medien“ der Bertelsmann Stiftung und der Heinz Nixdorf Stiftung erarbeitet wurde. 相似文献
9.
Corrosion resistance and galvanic coupling of Grade 2 commercially pure titanium in its welded and non-welded condition were systematically analyzed in LiBr solutions. Galvanic corrosion was evaluated through two different methods: anodic polarization (according to the Mixed Potential Theory) and electrochemical noise (using a zero-resistance ammeter). Samples have been etched to study the microstructure. The action of lithium chromate as corrosion inhibitor has been evaluated. Titanium and welded titanium showed extremely low corrosion current densities and elevated pitting potential values (higher than 1 V). The results of both methods, anodic polarization and electrochemical noise, showed that the welded titanium was always the anodic element of the pair titanium-welded titanium, so that its corrosion resistance decreases due to the galvanic effect. 相似文献
10.
Inmaculada Romero-Cascales José Ignacio Fernández-Fernández José María Ros-García José María López-Roca & Encarna Gómez-Plaza 《International Journal of Food Science & Technology》2008,43(7):1295-1305
Numerous studies have reported on the use of enzymes in wineries to facilitate the extraction of grape phenolics and to aid colour stability, although no clear conclusions were reached. Information concerning the enzymatic activities of industrial preparations is very difficult to obtain despite its importance. The aim of this work was to characterise and quantify the activities of six macerating enzyme preparations to optimise their use, and to study their effect on the chromatic characteristics of a Monastrell wine. The results indicate that differences exist in the type of enzymatic activities present in the preparations and in their concentration. The chromatic characteristics of the resulting wines, both at the end of alcoholic fermentation and after 12 months of storage in stainless steel tanks, showed differences with the use of the different maceration enzymes when comparing with control wine, although very little differences were observed between the different enzyme treatments. The enzyme-treated wines showed, at the end of alcoholic fermentation, a higher OD280 and tannin content, and after 12 months, a higher colour intensity too. The main effect of all the preparations was an increase in the total phenol content, probably by facilitating the release of skin tannins. 相似文献