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71.
This work describes a framework that combines techniques from Adaptive Hypermedia and Natural Language processing in order to create, in a fully automated way, on-line information systems from linear texts in electronic format, such as textbooks. The process is divided into two steps: an off-line processing step, which analyses the source text, and an on-line step, which executes when a user connects to the system with a web browser, moment at which the contents and hyperlinks are generated. The framework has been implemented as the Welkin system, which has been used to build three adaptive on-line information sites in a quick and easy way. Some controlled experiments have been performed with real users aimed to provide positive feedback on the implementation of the system. 相似文献
72.
Pilar García-Soidán 《TEST》2007,16(3):479-503
In this work, the Nadaraya–Watson semivariogram estimation is considered for both the isotropic and the anisotropic settings.
Several properties of these estimators are analyzed and, particularly, their asymptotic normality is established in terms
of unknown characteristics of the random process. The latter provides a theoretical procedure for construction of confidence
intervals for the semivariogram via the normal quantiles, which in practice must be appropriately estimated. A numerical study
is included to illustrate the performance of the Nadaraya–Watson estimation when used to obtain confidence intervals.
相似文献
73.
Unai De La Torre Beñat Pereda-Ayo Manuel Romero-Sáez Asier Aranzabal M. Pilar González-Marcos José A. González-Marcos Juan R. González-Velasco 《Topics in Catalysis》2013,56(1-8):215-221
The NOx NH3-SCR performance of several Cu and Fe catalysts supported on BETA and ZSM-5 zeolites has been studied in single SCR and double NSR–SCR configuration, and the activity related to the nature and reducibility of metal species on the catalyst surface. Intermediate ammonia formed in NSR improved greatly NOx conversion at the exit of the double NSR–SCR configuration, which was practically totally converted to N2. 相似文献
74.
Langenbucher James; Martin Christopher S.; Labouvie Erich; Sanjuan Pilar M.; Bavly Lawrence; Pollock Nancy K. 《Canadian Metallurgical Quarterly》2000,68(5):799
The Diagnostic and Statistical Manual of Mental Disorders-IV (DSM-IV) classifies as dependent many cases of mild alcohol problems. DSM-IV diagnoses have modest relationships with predictive and some concurrent validators and often improperly sequence the onset of abuse vs dependence, perhaps due to insufficient emphasis on physiological features. Testing reliability, syndrome prevalence, syndrome sequencing, and concurrent and predictive validity, this study contrasted the DSM-IV with the Withdrawal-Gate Model (WGM), in which alcohol withdrawal is necessary and sufficient for the dependence diagnosis. Clinical samples of adults (baseline n?=?318) and adolescents (baselinen?=?214) meeting abuse or dependence were assessed for DSM-IV alcohol symptoms and external measures of problem severity and reinterviewed at 6 (adults) and 12 mo (adults and adolescents). Among DSM-IV dependent cases, the WGM shifted 32% of adults and 80% of adolescents to the abuse category, making both categories more symptomatically severe, but had a negligible effect on prevalence of total alcohol diagnoses. The WGM was more reliable than the DSM-IV and temporally sequenced abuse before dependence in a greater number of cases. The WGM was superior to the DSM-IV in concurrent and predictive validity on most measures. Future diagnostic systems may be more reliable and valid if they require evidence of withdrawal for substance dependence. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
75.
Juan R. Gonz lez-Velasco Juan A. Botas Raquel Ferret M. Pilar Gonz lez-Marcos Jean-Louis Marc Miguel A. Guti rrez-Ortiz 《Catalysis Today》2000,59(3-4):395-402
Mono- and multi-metallic (bi- and tri-) Pt, Pd and Rh supported on cerium-promoted alumina (La Roche, SAS-1/16) catalysts were tested for activity as TWC, both fresh [G.C. Koltsakis, and A.M. Stamatelos, Progr. Energy Combust. Sci. 23 (1997) 1] and after accelerated aging. Aging consisted of a treatment at 900°C for 5 h during which an oxidizing (2.5% O2, 10% H2O, in N2) and a reducing (5.0% CO, 10% H2O, in N2) feedstream were cycled at 0.017 Hz through the catalyst. Activity tests were carried out by increasing temperature from 100 to 600°C at 3°C min−1, while two oxidizing and reducing (±0.5 A/F) feedstreams were alternately (1 Hz) fed through the reactor at 125 000 h−1 (STP). Conversion was continuously analyzed. Light-off temperature, T50, conversion at 500°C (normal running temperature), X500, and the stoichiometric window (A/F from 14.13 to 15.13) for stationary feedstreams, were determined. 相似文献
76.
This study examines adaptive responses that mental health professionals of color use to cope with racial microaggressions in their professional lives. Twenty-four mental health professionals from diverse ethnic backgrounds in the United States and Canada participated in focus groups discussing their experiences with racial microagressions and how they cope with them. Results of the analysis indicated that 8 primary coping themes illustrated strategies used by the participants. These include: identifying key issues in responding to racial microaggressions, self-care, spirituality, confrontation, support, documentation, mentoring, and collective organizing. Suggestions for mentoring professionals of color are offered. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
77.
Begoña Giménez Óscar Martínez-Alvarez Pilar Montero María del Carmen Gómez-Guillén 《LWT》2010,43(8):1240-1245
The characterization of phenoloxidase activity was performed in both carapace and viscera extracts of Norway lobster. Phenoloxidase activity rose with increasing temperature up to 60 °C. The carapace enzymatic extract showed the highest themostability, retaining about 80% of maximum activity at 45 °C and 40% at 65 °C. On the other hand, both enzymatic extracts showed a single peak activity at neutral-slightly alkaline pH and were quite resistant to inactivation at alkaline pH (pH > 8), but phenoloxidase activity became unstable at pH lower than 5.5. The enzymatic extract obtained from viscera showed a higher affinity for catechol (KM 5.97 mM) than carapace extract (KM 19.40 mM). Both mono- and diphenoloxidase activities were found in carapace and viscera. Polyphenoloxidase and converted-hemocyanin into PPO-like enzyme could be the main responsible for these activities. 相似文献
78.
This paper examines the physico-chemical characteristics of a natural kaolin, its textural properties, pores, morphology, chemical surface, as well as chemical surface modification through treatment with quaternary ammonium salts in SBR mixes. Diallyldimethylammonium chloride was used as a quaternary alkali for surface modification of the kaolin, thus allowing the unsaturated allyl portion to covulcanize with the rubber. This achieved strong rubber-filler bonds with consequential enhancement of the technological properties of the vulcanizate. 相似文献
79.
Factorial analyses were performed to determine the effect of high-pressure treatment on the characteristics of blue whiting
mince of good gel-forming quality. Pressure, time and temperature independently influenced gel characteristics. Temperature
had the greatest influence of the three. High-pressure gels were generally distinguished by lower adhesiveness, higher water-holding
capacity and less yellowness than heat-induced gels. The combination of pressure and temperature produced more elastic gels,
whereas gels made under high pressure at chilling temperatures were much harder, more deformable and more cohesive. There
was no correlation between elasticity and deformability. 相似文献
80.
Juana Bernabé Juana Mulero Begoña Cerdá Cristina García-Viguera Diego A. Moreno Soledad Parra Francisco Avilés Angel Gil-Izquierdo José Abellán Pilar Zafrilla 《Journal of Functional Foods》2013,5(3):1031-1038
Bioactive substances found in numerous foods can be successfully and safely used to modify various cellular functions and affect the oxidative stress. The aim of this study was to analyze the effect of a citrus-based juice (juice citrus (95%) with 5% of aronia extract (Aronia melanocarpa)) on biomarkers of oxidative stress in patients with metabolic syndrome compared with healthy individuals. The study comprised 20 healthy subjects and 33 patients with metabolic syndrome. Eighteen patients consumed daily 300 mL of a citrus-based juice during 6 months and 15 patients consumed 300 mL of a placebo beverage. The control group consumed a citrus-based juice (CJ). Before, and at sixth months after consuming of a citrus-based juice the following parameters were determined: 15-isoprostane F2, 8-hydroxydeoxyguanosine (8-OHdG), reduced and oxidized glutathione (GSH/GSSH), carbonyl groups and oxidized LDL (ox-LDL). After consuming CJ during 6 months the values of 8-OHdG, carbonyl groups and LDL-ox decreased in both analyzed groups and the values of GSH/GSSH increased. Significant differences were observed in both groups. Thus consumption of citrus-based juice improved the biomarkers of oxidative stress in metabolic syndrome patients. 相似文献