141 research outputs found

    A Practical Example for Model-Driven Web Requirements

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    The number of approaches for Web environments has grown very fast in the last years: HDM, OOHDM, and WSDM were among the first, and now a large number can be found in the literature. With the definition of MDA (Model- Driven Architecture) and the acceptance of MDE (Model-Driven Engineering) techniques in this environment, some groups are working in the use of metamodels and transformations to make their approaches more powerful. UWE (UMLBased Web Engineering) or OOWS (Object-Oriented Web Solutions) are only some examples. However, there are few real experiences with Web Engineering in the enterprise environment, and very few real applications of metamodels and MDE techniques. In this chapter the practical experience of a Web Engineering approach, NDT, in a big project developed in Andalusia is presented. Besides, it shows the usability of metamodels in real environments

    A Practical Environment to Apply Model-Driven Web Engineering

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    The application of a model-driven paradigm in the development of Web Systems has yielded very good research results. Several research groups are defining metamodels, transformations, and tools which offer a suitable environment, known as model-driven Web engineering (MDWE). However, there are very few practical experiences in real Web system developments using real development teams. This chapter presents a practical environment of MDWE based on the use of NDT (navigational development techniques) and Java Web systems, and it provides a practical evaluation of its application within a real project: specialized Diraya.Ministerio de Educación y Ciencia TIN2007-67843-C06-03Ministerio de Educación y Ciencia TIN2007-30391-

    Effect of Ionizing Radiation Applied to PLA Used as Compatibilizing Agent in Reinforced eGG Shell PBAT/PLA Bio-Based Composites

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    Bio-filler from eggshells as reinforcement of bio-based polymers are based on their benefits as adequate strength and stiffness, besides friendly, degradable and renewable environment. Eggshell is an agricultural waste considered as garbage, contributing to pollution; nevertheless, it can be transformed into bio-calcium carbonate, acquiring new values. As biodegradable polymers, there were chosen PLA (poly-lactic-acid) and PBAT (butylene adipate co-terephthalate), thermoplastics capable to be processed via conventional methods. PLA is a linear, aliphatic thermoplastic polyester, high in strength and modulus, but brittle. PBAT is a synthetic polymer, very flexible, based on fossil resources with high elongation at break, but low strength. It will be required the use of compatibilizers, for reducing interfacial tension exhibited by PLA/PBAT immiscible blend, considering their extreme glass transition temperatures: 62 o C for PLA and – 30 o C for PBAT. Herein it was used ionizing radiation for inducing compatibilization by free radicals, improving dispersion and adhesion of blend phases, without using chemical additives, at room temperature. PLA, acting as compatibilizer, was previously e-beam and gamma radiated, at 150 kGy. PBAT/PLA 50/50 blend with 15 phr of bio-filler from avian eggs 125 µm particle size and both compatibilizers were homogeneized in a co-rotating twin-screw extruder, within a temperature profile 120 to 145 o C, from hopper to die. Characterization involved: Differential Scanning Calorimeter, Thermogravimetric Analyses, Fourier Transform Infrared Spectroscopy, Wide Angle X-Ray Diffraction, Tensile Strength and Elongation at Break

    Study of Bio-Based Foams Prepared from PBAT/PLA Reinforced with Bio-Calcium Carbonate and Compatibilized with Gamma Radiation

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    Foamed polymers are future materials, considered “green materials” due to their properties with very low consumption of raw materials; they can be used to ameliorate appearance of structures besides contributing for thermal and acoustic insulation. Nevertheless, waste disposal has generated about 20–30% of total of solid volume in landfills besides prejudicing flora and fauna by uncontrolled disposal. The development of biodegradable polymers aims to solve this problem, considering that in 2012, bio-plastics market was evaluated in 1.4 million tons produced and in 2017 attained 6.2 million tons. Biodegradable polymers as poly(lactic acid) (PLA) and poly(butylene adipate-co-terephthalate) (PBAT) are thermoplastics which can be processed using the most conventional polymer processing methods. PLA is high in strength and modulus but brittle, while PBAT is flexible and tough. In order to reduce interfacial tension exhibited by PLA/PBAT blends, it was used as compatibilizing agent 5 phr of PLA previously gamma-radiated at 150 kGy. Ionizing radiation induces compatibilization by free radicals, improving the dispersion and adhesion of blend phases, without using chemical additives and at room temperature. As a reinforcement agent, calcium carbonate from avian eggshell waste was used, at 10 ph of micro particles, 125 μm. Admixtures were further processed in a single-screw extruder, using CO2 as physical blowing agent (PBA). Property investigations were performed by DSC, TGA, XRD, SEM, FTIR, and mechanical essays

    Validation of a new optical diagnosis training module to improve dysplasia characterization in inflammatory bowel disease:a multicenter international study

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    Background and aims Inflammatory bowel disease (IBD) increases risk of dysplasia and colorectal cancer. Advanced endoscopic techniques allow for the detection and characterization of IBD dysplastic lesions, but specialized training is not widely available. We aim to develop and validate an online training platform to improve the detection and characterization of colonic lesions in IBD: OPTIC-IBD. Methods We designed a web-based learning module that includes surveillance principles, optical diagnostic methods, approach to characterization, classifications of colonic lesions, utilizing still images and videos. We invited gastroenterologists from Canada, Italy, and the UK, with a wide range of experience. Participants reviewed 24 educational videos of IBD colonic lesions, predicted histology, and rated their confidence. The primary endpoint was to improve accuracy in detecting dysplastic lesions following training on the platform. Furthermore, participants were randomized 1:1 to get additional training or not, with a final assessment occurring after 60 days. Diagnostic performance for dysplasia and rater confidence were measured. Results One hundred seventeen participants completed the study and were assessed for the primary endpoint. Diagnostic accuracy improved from 70.8% to 75.0% (p 0.002) following training, with the greatest improvements seen in less experienced endoscopists. Improvements in both accuracy and confidence were sustained after 2 months of assessment, although the group randomized to receive additional training did not improve further. Similarly, participants’ confidence in characterizing lesions significantly improved between pre- and post-course (

    Search for direct production of charginos and neutralinos in events with three leptons and missing transverse momentum in √s = 7 TeV pp collisions with the ATLAS detector

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    A search for the direct production of charginos and neutralinos in final states with three electrons or muons and missing transverse momentum is presented. The analysis is based on 4.7 fb−1 of proton–proton collision data delivered by the Large Hadron Collider and recorded with the ATLAS detector. Observations are consistent with Standard Model expectations in three signal regions that are either depleted or enriched in Z-boson decays. Upper limits at 95% confidence level are set in R-parity conserving phenomenological minimal supersymmetric models and in simplified models, significantly extending previous results

    Jet size dependence of single jet suppression in lead-lead collisions at sqrt(s(NN)) = 2.76 TeV with the ATLAS detector at the LHC

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    Measurements of inclusive jet suppression in heavy ion collisions at the LHC provide direct sensitivity to the physics of jet quenching. In a sample of lead-lead collisions at sqrt(s) = 2.76 TeV corresponding to an integrated luminosity of approximately 7 inverse microbarns, ATLAS has measured jets with a calorimeter over the pseudorapidity interval |eta| < 2.1 and over the transverse momentum range 38 < pT < 210 GeV. Jets were reconstructed using the anti-kt algorithm with values for the distance parameter that determines the nominal jet radius of R = 0.2, 0.3, 0.4 and 0.5. The centrality dependence of the jet yield is characterized by the jet "central-to-peripheral ratio," Rcp. Jet production is found to be suppressed by approximately a factor of two in the 10% most central collisions relative to peripheral collisions. Rcp varies smoothly with centrality as characterized by the number of participating nucleons. The observed suppression is only weakly dependent on jet radius and transverse momentum. These results provide the first direct measurement of inclusive jet suppression in heavy ion collisions and complement previous measurements of dijet transverse energy imbalance at the LHC.Comment: 15 pages plus author list (30 pages total), 8 figures, 2 tables, submitted to Physics Letters B. All figures including auxiliary figures are available at http://atlas.web.cern.ch/Atlas/GROUPS/PHYSICS/PAPERS/HION-2011-02
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