42 resultados para Stone tools
Resumo:
Two of the drawbacks of using natural-based composites in industrial applications are thermal instability and water uptake capacity. In this work, mechanical wood pulp was used to reinforce polypropylene at a level of 20 to 50 wt. %. Composites were mixed by means of a Brabender internal mixer for both non-coupled and coupled formulations. Differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA) were used to determine the thermal properties of the composites. The water uptake behavior was evaluated by immersion of the composites in water until an equilibrium state was reached. Results of water absorption tests revealed that the amount of water absorption was clearly dependent upon the fiber content. The coupled composites showed lower water absorption compared to the uncoupled composites. The incorporation of mechanical wood pulp into the polypropylene matrix produced a clear nucleating effect by increasing the crystallinity degree of the polymer and also increasing the temperature of polymer degradation. The maximum degradation temperature for stone ground wood pulp–reinforced composites was in the range of 330 to 345 ºC
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The behavior of stone groundwood / polypropylene injection-molded composites was evaluated with and without coupling agent. Stone groundwood (SGW) is a fibrous material commonly prepared in a high yield process and mainly used for papermaking applications. In this work, the use of SGW fibers was explored as a reinforcing element of polypropylene (PP) composites. The surface charge density of the composite components was evaluated, as well as the fiber’s length and diameter inside the composite material. Two mixing extrusion processes were evaluated, and the use of a kinetic mixer, instead of an internal mixer, resulted in longer mean fiber lengths of the reinforcing fibers. On the other hand, the accessibility of surface hydroxyl groups of stone groundwood fibers was improved by treating the fibers with 5% of sodium hydroxide, resulting in a noticeable increase of the tensile strength of the composites, for a similar percentage of coupling agent. A new parameter called Fiber Tensile Strength Factor is defined and used as a baseline for the comparison of the properties of the different composite materials. Finally the competitiveness of stone groundwood / polypropylene / polypropylene-co-maleic anhydride system, which compared favorably to sized glass-fiber / polypropylene GF/PP and glass-fiber / polypropylene / polypropylene-co-maleic anhydride composite formulations, was quantified by means of the fiber tensile strength factor
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This work briefly analyses the difficulties to adopt the Semantic Web, and in particular proposes systems to know the present level of migration to the different technologies that make up the Semantic Web. It focuses on the presentation and description of two tools, DigiDocSpider and DigiDocMetaEdit, designed with the aim of verifYing, evaluating, and promoting its implementation.
Resumo:
En aquest projecte he avaluat un seguit de plataformes per veure quina era la millor pertal d’integrar les eines que proporcionen serveis del projecte TENCompetence.Per començar el projecte plantejaré el context del projecte. Com se situa al marc del projecte TENCompetence on he desenvolupat aquest treball fi de carrera. Tot seguit es veuen quines eines disposem per tal d’accedir als diferents serveis que ens proporciona el projecte.Comento els escenaris on s’aplicarà la tecnologia que triem i finalment comento les diferents plataformes web on integrarem les diferents eines.A continuació he realitzat un capítol per tal de comentar l’anàlisi de requeriments del’escenari d’aplicació de cada pilot. Per a cada escenari aplico unes determinades eines a un determinat context, i per tant hi han unes necessitats concretes que he de recollir. Per plasmar-ho en paper he realitzat l’anàlisi de requeriments. Un cop recollides totes les dades he pogut feruna selecció de la plataforma contenidora que més s’escau a cada pilot.Amb els requeriments i la plataforma seleccionada, he realitzat un disseny per a cada pilot. Després de refinar el disseny he realitzat la implementació per tal de cobrir les necessitats dels pilots. També he aprofitat per veure quina tecnologia es pot utilitzar per tal d’integrar leseines dins de la plataforma.Amb la implementació feta he realitzat un seguit de proves per tal de veure els resultats aconseguits. Tot seguit he iniciat un procés iteractiu per tal refinar el disseny i millorar la implementació.
Resumo:
When the behaviour of a specific hypothesis test statistic is studied by aMonte Carlo experiment, the usual way to describe its quality is by givingthe empirical level of the test. As an alternative to this procedure, we usethe empirical distribution of the obtained \emph{p-}values and exploit itsinformation both graphically and numerically.
Resumo:
El projecte de TAV es basa en la transferència d'un sistema de vals de capacitació, i en com aquest sistema de vals és adaptable a altres països o regions. En el document s'analitzen diferents conceptes teòrics sobre la conveniència o no de la implantació d'aquest sistema. A més a més, aquest document és una guia per a les organitzacions interessades en l'adaptació del sistema de vals formatius al seu territori, mostrant els passos a seguir i oferint eines útils per aconseguir-ho.
Resumo:
El projecte de TAV es basa en la transferència d'un sistema de vals de capacitació, i en com aquest sistema de vals és adaptable a altres països o regions. En el document s'analitzen diferents conceptes teòrics sobre la conveniència o no de la implantació d'aquest sistema. A més a més, aquest document és una guia per a les organitzacions interessades en l'adaptació del sistema de vals formatius al seu territori, mostrant els passos a seguir i oferint eines útils per aconseguir-ho.
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The genus Artemisia is one of the largest of the Asteraceae family, with more than 500 species. It is widely distributed mainly across the Northern Hemisphere, being profusely represented in the Old World, with a great centre of diversification in Asia, and also reaching the New World. The evolution of this genus has been deeply studied using different approaches, and polyploidy has been found to perform an important role leading to speciation processes. Karyological, molecular cytogenetic and phylogenetic data have been compiled in the present review to provide a genomic characterization throughout some complexes within the genus.
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In past years, comprehensive representations of cell signalling pathways have been developed by manual curation from literature, which requires huge effort and would benefit from information stored in databases and from automatic retrieval and integration methods. Once a reconstruction of the network of interactions is achieved, analysis of its structural features and its dynamic behaviour can take place. Mathematical modelling techniques are used to simulate the complex behaviour of cell signalling networks, which ultimately sheds light on the mechanisms leading to complex diseases or helps in the identification of drug targets. A variety of databases containing information on cell signalling pathways have been developed in conjunction with methodologies to access and analyse the data. In principle, the scenario is prepared to make the most of this information for the analysis of the dynamics of signalling pathways. However, are the knowledge repositories of signalling pathways ready to realize the systems biology promise? In this article we aim to initiate this discussion and to provide some insights on this issue.
Resumo:
PURPOSE: Pharmacovigilance methods have advanced greatly during the last decades, making post-market drug assessment an essential drug evaluation component. These methods mainly rely on the use of spontaneous reporting systems and health information databases to collect expertise from huge amounts of real-world reports. The EU-ADR Web Platform was built to further facilitate accessing, monitoring and exploring these data, enabling an in-depth analysis of adverse drug reactions risks.METHODS: The EU-ADR Web Platform exploits the wealth of data collected within a large-scale European initiative, the EU-ADR project. Millions of electronic health records, provided by national health agencies, are mined for specific drug events, which are correlated with literature, protein and pathway data, resulting in a rich drug-event dataset. Next, advanced distributed computing methods are tailored to coordinate the execution of data-mining and statistical analysis tasks. This permits obtaining a ranked drug-event list, removing spurious entries and highlighting relationships with high risk potential.RESULTS: The EU-ADR Web Platform is an open workspace for the integrated analysis of pharmacovigilance datasets. Using this software, researchers can access a variety of tools provided by distinct partners in a single centralized environment. Besides performing standalone drug-event assessments, they can also control the pipeline for an improved batch analysis of custom datasets. Drug-event pairs can be substantiated and statistically analysed within the platform's innovative working environment.CONCLUSIONS: A pioneering workspace that helps in explaining the biological path of adverse drug reactions was developed within the EU-ADR project consortium. This tool, targeted at the pharmacovigilance community, is available online at https://bioinformatics.ua.pt/euadr/. Copyright © 2012 John Wiley & Sons, Ltd.
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Aquest és el llibre més complet que hi ha sobre la pedra de Santa Tecla i el llisós, dos materials procedents de Tarragona i molt utilitzats en època romana. Els autors, arqueòlegs i geòlegs, caracteritzen aquestes dues varietats i presenten el panorama de les seves aplicacions, i també donen pautes per identificar-les i diferenciar-les d’altres pedres que s’hi podrien confondre, com la “portasanta” o la pedra de Buixcarró.
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A table showing a comparison and classification of tools (intelligent tutoring systems) for e-learning of Logic at a college level.
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This documents sums up a projectaimed at building a new web interfaceto the Apertium machine translationplatform, including pre-editing andpost-editing environments. It containsa description of the accomplished workon this project, as well as an overviewof possible evolutions.