764 resultados para Alloy, UML, OCL


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In this session we look at how to model flow of control and interactions between components using UML Activity and Sequence Diagrams. This is an introductory session and so for Activity Diagrams we only cover branching, forks and joins and swim lanes, and for Sequence we cover lifelines, messages and returns, and alt, par and opt frames.

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In this session we look at UML Class Diagrams and how they fit into both the family of UML models, and also the software engineering process. We look at some basic features of class diagrams including properties, operations, associations, generalisation, aggregation and composition.

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El artículo está incluido en un número monográfico especial con los trabajos del I Simposio Pluridisciplinar sobre Diseño, Evaluación y Descripción de Contenidos Educativos Reutilizables (Guadalajara, Octubre 2004).Resumen tomado de la publicación

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The Heusler alloy Ni50 Mn37 Sn13 was successfully produced as ribbon flakes of thickness around 7-10 μm melt spinning. Fracture cross section micrographs in the ribbon show the formation of a microcrystalline columnarlike microstructure, with their longer axes perpendicular to the ribbon plane. Phase transition temperatures of the martensite-austenite transformation were found to be MS =218 K, Mf =207 K, AS =224 K, and Af =232 K; the thermal hysteresis of the transformation is 15 K. Ferromagnetic L 21 bcc austenite phase shows a Curie point of 313 K, with cell parameter a=0.5971 (5) nm at 298 K, transforming into a modulated 7M orthorhombic martensite with a=0.6121 (7) nm, b=0.6058 (8) nm, and c=0.5660 (2) nm, at 150 K

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RESUMO: O conhecimento existe desde sempre, mesmo num estado latente condicionado algures e apenas à espera de um meio (de uma oportunidade) de se poder manifestar. O conhecimento é duplamente um fenómeno da consciência: porque dela procede num dado momento da sua vida e da sua história e porque só nela termina, aperfeiçoando-a e enriquecendo-a. O conhecimento está assim em constante mudança. À relativamente pouco tempo começou-se a falar de Gestão do Conhecimento e na altura foi muito associada às Tecnologias da Informação, como meio de colectar, processar e armazenar cada vez mais, maiores quantidades de informação. As Tecnologias da Informação têm tido, desde alguns anos para cá, um papel extremamente importante nas organizações, inicialmente foram adoptadas com o propósito de automatizar os processos operacionais das organizações, que suportam as suas actividades quotidianas e nestes últimos tempos as Tecnologias da Informação dentro das organizações têm evoluído rapidamente. Todo o conhecimento, mesmo até o menos relevante de uma determinada área de negócio, é fundamental para apoiar o processo de tomada de decisão. As organizações para atingirem melhores «performances» e conseguirem transcender as metas a que se propuseram inicialmente, tendem a munir-se de mais e melhores Sistemas de Informação, assim como, à utilização de várias metodologias e tecnologias hoje em dia disponíveis. Por conseguinte, nestes últimos anos, muitas organizações têm vindo a demonstrar uma necessidade crucial de integração de toda a sua informação, a qual está dispersa pelos diversos departamentos constituintes. Para que os gestores de topo (mas também para outros funcionários) possam ter disponível em tempo útil, informação pertinente, verdadeira e fiável dos negócios da organização que eles representam, precisam de ter acesso a bons Sistemas de Tecnologias de Informação. Numa acção de poderem agir mais eficazmente e eficientemente nas tomadas de decisão, por terem conseguido tirar por esses meios o máximo de proveito possível da informação, e assim, apresentarem melhores níveis de sucesso organizacionais. Também, os Sistemas de «Business Intelligence» e as Tecnologias da Informação a ele associadas, utilizam os dados existentes nas organizações para disponibilizar informação relevante para as tomadas de decisão. Mas, para poderem alcançar esses níveis tão satisfatórios, as organizações necessitam de recursos humanos, pois como podem elas serem competitivas sem Luís Miguel Borges – Gestão e Trabalhadores do Conhecimento em Tecnologias da Informação (UML) ULHT – ECATI 6 trabalhadores qualificados. Assim, surge a necessidade das organizações em recrutar os chamados hoje em dia “Trabalhadores do Conhecimento”, que são os indivíduos habilitados para interpretar as informações dentro de um domínio específico. Eles detectam problemas e identificam alternativas, com os seus conhecimentos e discernimento, eles trabalham para solucionar esses problemas, ajudando consideravelmente as organizações que representam. E, usando metodologias e tecnologias da Engenharia do Conhecimento como a modelação, criarem e gerirem um histórico de conhecimento, incluindo conhecimento tácito, sobre várias áreas de negócios da organização, que podem estar explícitos em modelos abstractos, que possam ser compreendidos e interpretados facilmente, por outros trabalhadores com níveis de competência equivalentes. ABSTRACT: Knowledge has always existed, even in a latent state conditioning somewhere and just waiting for a half (an opportunity) to be able to manifest. Knowledge is doubly a phenomenon of consciousness: because proceeds itself at one point in its life and its history and because solely itself ends, perfecting it and enriching it. The knowledge is so in constant change. In the relatively short time that it began to speak of Knowledge Management and at that time was very associated with Information Technologies, as a means to collect, process and store more and more, larger amounts of information. Information Technologies has had, from a few years back, an extremely important role in organizations, were initially adopted in order to automate the operational processes of organizations, that support their daily activities and in recent times Information Technologies within organizations has evolved rapidly. All the knowledge, even to the least relevant to a particular business area, is fundamental to support the process of decision making. The organizations to achieve better performances and to transcend the goals that were initially propose, tend to provide itself with more and better Information Systems, as well as, the use of various methodologies and technologies available today. Consequently, in recent years, many organizations have demonstrated a crucial need for integrating all their information, which is dispersed by the diver constituents departments. For top managers (but also for other employees) may have ready in time, pertinent, truthful and reliable information of the organization they represent, need access to good Information Technology Systems. In an action that they can act more effectively and efficiently in decision making, for having managed to get through these means the maximum possible advantage of the information, and so, present better levels of organizational success. Also, the systems of Business Intelligence and Information Technologies its associated, use existing data on organizations to provide relevant information for decision making. But, in order to achieve these levels as satisfactory, organizations need human resources, because how can they be competitive without skilled workers. Thus, arises the need for organizations to recruit called today “Knowledge Workers”, they are the individuals enable to interpret the information within a specific domain. They detect problems and identify alternatives, with their knowledge and discernment they work to solve these problems, helping considerably the organizations that represent. And, using Luís Miguel Borges – Gestão e Trabalhadores do Conhecimento em Tecnologias da Informação (UML) ULHT – ECATI 8 methodologies and technologies of Knowledge Engineering as modeling, create and manage a history of knowledge, including tacit knowledge, on various business areas of the organization, that can be explicit in the abstract models, that can be understood and interpreted easily, by other workers with equivalent levels of competence.

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We have used synchrotron-based high-resolution X-ray photoelectron spectroscopy in combination with ab initio density functional theory calculations to investigate the characteristics of water and CO adsorption on the bimetallic Cu/Pt{110}-(2 x 1) surface at a Cu coverage near 0.5 ML. Cu fills the troughs of the reconstructed clean surface forming nanowires, which are stable up to 830 K. Their presence dramatically influences the adsorption of water and CO. Water adsorption changes from intact to partially dissociated while the desorption temperature of CO on this surface increases by up to 27 K with respect to the clean Pt{110} surface. Ab initio calculations and experimental valence band spectra reveal that the Cu 3d-band is narrowed and shifted upward with respect to bulk Cu surfaces. This and electron donation to surface Pt atoms cause the increase in the bond strength between CO and the Pt surface atoms. The pathway for water dissociation occurs via Cu surface atoms. The heat of adsorption of water bonding to Cu surface atoms was calculated to be 0.82 eV, which is significantly higher than on the clean Pt{110} surface; the activation energy for partial dissociation is 0.53 eV (not corrected for zero point energy).

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Templated sol-gel encapsulation of surfactant-stabilised micelles containing metal precursor(s) with ultra-thin porous silica coating allows solvent extraction of organic based stabiliser from the composites in colloidal state hence a new method of preparing supported alloy catalysts using the inorganic silica-stabilised nano-sized, homogenously mixed, silver - platinum (Ag-Pt) colloidal particles is reported.

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Statement of problem. In vitro studies on the retentive strengths of various cements used to retain posts have reported conflicting results. Purpose. The purpose of this study was to compare the tensile strength of commercially pure titanium and type III cast gold-alloy posts and cores cemented with zinc phosphate or resin cement. Material and methods. Forty-two extracted human canines were endoclontically treated. The root preparations were accomplished using Largo reamers (10 mm in depth and 1.7 mm in diameter). Acrylic resin patterns for the posts and cores were made, and specimens were cast in commercially pure titanium and in type III gold alloy (n=7). Fourteen titanium cast posts and cores were submitted to surface treatment with Kroll acid solution and to scanning electron microscopy (SEM), before and after acid etching. The groups (n=7) were cemented with zinc phosphate cement or resin cement (Panavia F). Tensile strengths were measured in a universal testing machine at a crosshead speed of 0.5 mm/min. The results (Kgf) were statistically analyzed by 2-way ANCIVA (alpha=.05). Results. The 2-way ANOVA indicated that there were no significant differences among the groups tested. Retentive means for zinc phosphate and Panavia F cements were statistically similar. The bond strength was not Influenced by the alloy, the luting material, or the etching treatment. SEM analysis indicated that the etched surfaces were smoother than those that did not receive surface treatment, but this fact did not influence the results. Conclusions. Commercially pure titanium cast posts and cores cemented with zinc phosphate and resin cements demonstrated similar mean tensile retentive values. Retentive values were also similar to mean values recorded for cast gold-alloy posts and cores cemented with zinc phosphate cement and resin cements.

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P>This study aimed to verify the effect of modified section method and laser-welding on the accuracy of fit of ill-fitting commercially pure titanium (cp Ti) and Ni-Cr alloy one-piece cast frameworks. Two sets of similar implant-supported frameworks were constructed. Both groups of six 3-unit implant-supported fixed partial dentures were cast as one-piece [I: Ni-Cr (control) and II: cp Ti] and evaluated for passive fitting in an optical microscope with both screws tightened and with only one screw tightened. All frameworks were then sectioned in the diagonal axis at the pontic region (III: Ni-Cr and IV: cp Ti). Sectioned frameworks were positioned in the matrix (10-Ncm torque) and laser-welded. Passive fitting was evaluated for the second time. Data were submitted to anova and Tukey-Kramer honestly significant difference tests (P < 0 center dot 05). With both screws tightened, one-piece cp Ti group II showed significantly higher misfit values (27 center dot 57 +/- 5 center dot 06 mu m) than other groups (I: 11 center dot 19 +/- 2 center dot 54 mu m, III: 12 center dot 88 +/- 2 center dot 93 mu m, IV: 13 center dot 77 +/- 1 center dot 51 mu m) (P < 0 center dot 05). In the single-screw-tightened test, with readings on the opposite side to the tightened side, Ni-Cr cast as one-piece (I: 58 center dot 66 +/- 14 center dot 30 mu m) was significantly different from cp Ti group after diagonal section (IV: 27 center dot 51 +/- 8 center dot 28 mu m) (P < 0 center dot 05). On the tightened side, no significant differences were found between groups (P > 0 center dot 05). Results showed that diagonally sectioning ill-fitting cp Ti frameworks lowers misfit levels of prosthetic implant-supported frameworks and also improves passivity levels of the same frameworks when compared to one-piece cast structures.

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OWL-S is an application of OWL, the Web Ontology Language, that describes the semantics of Web Services so that their discovery, selection, invocation and composition can be automated. The research literature reports the use of UML diagrams for the automatic generation of Semantic Web Service descriptions in OWL-S. This paper demonstrates a higher level of automation by generating complete complete Web applications from OWL-S descriptions that have themselves been generated from UML. Previously, we proposed an approach for processing OWL-S descriptions in order to produce MVC-based skeletons for Web applications. The OWL-S ontology undergoes a series of transformations in order to generate a Model-View-Controller application implemented by a combination of Java Beans, JSP, and Servlets code, respectively. In this paper, we show in detail the documents produced at each processing step. We highlight the connections between OWL-S specifications and executable code in the various Java dialects and show the Web interfaces that result from this process.

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Films of isotropic nanocrystalline Pd(80)Co(20) alloys were obtained by electrodeposition onto brass substrate in plating baths maintained at different pH values. Increasing the pH of the plating bath led to an increase in mean grain size without inducing significant changes in the composition of the alloy. The magnetocrystalline anisotropy constant was estimated and the value was of the same order of magnitude as that reported for samples with perpendicular magnetic anisotropy. First order reversal curve (FORC) analysis revealed the presence of an important component of reversible magnetization. Also, FORC diagrams obtained at different sweep rate of the applied magnetic field, revealed that this reversible component is strongly affected by kinetic effect. The slight bias observed in the irreversible part of the FORC distribution suggested the dominance of magnetizing intergrain exchange coupling over demagnetizing dipolar interactions and microstructural disorder. (c) 2009 Elsevier B.V. All rights reserved.

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The nature of the protective film formed by benzotriazole (BTAH) on the surface of the 90/10 CuNi alloy in deaerated 0.5 mol L-1 H2SO4 solution containing Fe(III) ions as oxidant was investigated by weight-loss, calorimetric measurements, and by surface-enhanced Raman spectroscopy (SERS). The SERS measurements show that the protective film is composed by the [Cu(I)BTA](n), polymeric complex and that the BTAH molecules are also adsorbed on the electrode surface. A modification of the BET isotherm for adsorption of gases ill solids is proposed to describe the experimental results obtained from weight-loss experiments that suggest an adsorption in multilayers. Electrochemical studies of copper and nickel in 0.5 mol L-1 H2SO4 in presence and absence of BTAH have also been made as an aid to interpret the results. The calculated adsorption free energy of the cuprous benzotriazolate on the surface of the alloy is in accordance with the value for pure copper. (C) 2007 Elsevier Ltd. All rights reserved.

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Scanning electrochemical microscopy (SECM) in feedback mode was employed to characterise the reactivity and microscopic peculiarities of bismuth and bismuth/lead alloys plated onto gold disk substrates in 0.1 molL(-1) NaOH solutions. Methyl viologen was used as redox mediator, while a platinum microelectrode was employed as the SECM tip. The metal films were electrodeposited ex situ from NaOH solutions containing either bismuth ions only or both bismuth and lead ions. Approach curves and SECM images indicated that the metal films were conductive and locally reactive with oxygen to provide Bi(3+) and Pb(2+) ions. The occurrence of the latter chemical reactions was verified by local anodic stripping voltammetry (ASV) at the substrate solution interface by using a mercury-coated platinum SECM tip. The latter types of measurements allowed also verifying that lead was not uniformly distributed onto the bismuth film electrode substrate. These findings were confirmed by scanning electron microscopy images. The surface heterogeneity produced during the metal deposition process, however, did not affect the analytical performance of the bismuth coated gold electrode in anodic stripping voltammetry for the determination of lead in alkaline media, even in aerated aqueous solutions. Under the latter conditions, stripping peak currents proportional to lead concentration with a satisfactory reproducibility (within 5% RSD) were obtained.

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The Mg-Ni metastable alloys (with amorphous or nanocrystalline structures) are promising candidates for anode application in nickel-metal hydride rechargeable batteries due to its large hydrogen absorbing capacity, low weight, availability, and relative low price. In spite of these interesting features, improvement on the cycle life performance must be achieved to allow its application in commercial products. In the present paper, the effect of mechanical coating of a Mg-50 at.% Ni alloy with Ni and Ni-5 at.% Al on the structure, powder morphology, and electrochemical properties is investigated. The coating additives, Mg-Ni alloy and resulting nanocomposites (i.e., Mg-Ni alloy + additive) were investigated by means of X-ray diffraction and scanning electron microscopy. The Mg-Ni alloy and nanocomposites were submitted to galvanostatic cycles of charge and discharge to evaluate their electrode performances. The mechanical coating with Ni and Ni-5% Al increased the maximum discharge capacity of the Mg-Ni alloy from of 221 to 257 and 273 mA h g(-1), respectively. Improvement on the cycle life performance was also achieved by mechanical coating.