Uma ferramenta de análise automatizada de técnicas de seleção de testes de regressão baseada em mineração de repositórios de software

The main goal of Regression Test (RT) is to reuse the test suite of the latest version of a software in its current version, in order to maximize the value of the tests already developed and ensure that old features continue working after the new changes. Even with reuse, it is common that not all tests need to be executed again. Because of that, it is encouraged to use Regression Tests Selection (RTS) techniques, which aims to select from all tests, only those that reveal faults, this reduces costs and makes this an interesting practice for the testing teams. Several recent research works evaluate the quality of the selections performed by RTS techniques, identifying which one presents the best results, measured by metrics such as inclusion and precision. The RTS techniques should seek in the System Under Test (SUT) for tests that reveal faults. However, because this is a problem without a viable solution, they alternatively seek for tests that reveal changes, where faults may occur. Nevertheless, these changes may modify the execution flow of the algorithm itself, leading some tests no longer exercise the same stretch. In this context, this dissertation investigates whether changes performed in a SUT would affect the quality of the selection of tests performed by an RTS, if so, which features the changes present which cause errors, leading the RTS to include or exclude tests wrongly. For this purpose, a tool was developed using the Java language to automate the measurement of inclusion and precision averages achieved by a regression test selection technique for a particular feature of change. In order to validate this tool, an empirical study was conducted to evaluate the RTS technique Pythia, based on textual differencing, on a large web information system, analyzing the feature of types of tasks performed to evolve the SUT

Ativos intangíveis (modelo RBV) como recurso estratégico e competitivo: um estudo em hotéis de pequeno porte (zona sul, Natal/RN)

The study aims to analyze the perception of managers on intangible assets as strategic and competitive resources in small hotels in Natal/RN, through the theory of the Resource Based View (RBV). This is a qualitative study of exploratory and descriptive, conducted with managers of the means of hosting small the capital of Rio Grande do Norte through semi-structured interviews, which was applied later, the technique content analysis based on the results of the information obtained in the interviews. Thus, research has shown that managers of small hotels visited (A, B, C) are not sufficient and satisfactory knowledge to set as their unique intangible assets of the company and makes use of them, on an occasional basis, without understanding or in essence understand its true value as a resource that can be used strategically for sustainable competitive advantage in the hotel market in Natal/RN. This means that managers do not know how to create new attributes and use them strategically. And they need to expand their partnerships with stakeholders. Given the importance of the subject of the present research, the information achieved by this analysis may contribute to the provision of information to establish a current situation with regard to the attributed to the knowledge and use of resources (intangible assets) importance as a strategic source and competitive for the internal management of the company by managers and thus, enabling a differential and greater economic profit over time in this segment

Estrutura e desempenho organizacional: uma análise na Universidade Federal do Rio Grande do Norte

This research analyses the components of the organizational structure of the UFRN (Rio Grande do Norte Federal University) and to what extent they affect organizational performance. The study, classified as exploratory and descriptive, was conducted in two phases. The first phase consists of a pilot test to refine the research instrument and to identify the latent components of the organizational structure, and the second to characterize these components and thereby establish relationships with organizational performance. In the first phase, the research was conducted in 20 UFRN organizational units with the participation of 84 employees between technical-administrative and teachers, after considering missing values and outliers, while the second phase occurred in two stages: one conducted with 279 valid cases, consisting of technical-administrative and teachers of 37 UFRN units, and another with 112 managers of the institution in the 49 units identified in this research. The instrument adopted in the first phase was composed of 36 indicators of organizational structure, with six extracted and adapted from the instrument developed by Medeiros (2003) and 30 prepared based on the literature review, from Mintzberg (2012), Hall (1984), Vasconcellos and Hemsley (1997) and Seiffert and Costa (2007) and 7 performance indicators adapted from Fleury and Mills (2006), Vieira and Vieira (2003) and Kaplan and Norton (1997) from the self-assessment instrument in use by the university. In this stage the data were analyzed using the techniques of factor analysis and reliability analysis by means of Cronbach’s alpha, aiming to extract the factors representing the components of the organizational structure. In step 1 of the second phase, the instrument, refined and reduced in the previous phase, with 24 variables of organizational structure and 6 for performance was used, while in step 2, a semi-structured interview guide with questions, organized into nine organizational structure elements, was adopted aiming to gather information to understand the relationship of structure to performance of the UFRN. The techniques used in the second phase, as a whole, were factor analysis and reliability analysis to characterize the components extracted in the previous phase and to validate the performance variables and correlation analysis, regression and content analysis to establish and understand the relationship between structure and performance. The results showed, in the two stages, six latent components of organizational structure in the context under study: training and internalization, communication, hierarchy, decentralization, formalization and departmentalization - with high levels of Cronbach's alpha indexes - which can thereby be characterized as components of UFRN structure. Six performance indicators were validated in this study, showing them as efficient and highly reliable. Finally, it was found that the formalization, communication, decentralization, training and internalization components positively affect UFRN performance, while departmentalization has an adverse affect and hierarchy did not show a significant relationship. The results achieved in this work are important in future studies to support the development of a model structure that represents the specifics of the university

Efeito da moagem de alta energia na densificação e microestrutura do compósito AI2O3-Cu

The Cu-Al2O3 composite ceramic combines the phase of alumina, which is extremely hard and durable, yet very brittle, to metallic copper phase high ductility and high fracture toughness. These characteristics make this material a strong candidate for use as a cutting tool. Al2O3-Cu composite powders nanocrystalline and high homogeneity can be produced by high energy milling, as well as dense and better mechanical structures can be obtained by liquid phase sintering. This work investigates the effect of high-energy milling the dispersion phase Al2O3, Cu, and the influence of the content of Cu in the formation of Cu-Al2O3 composite particles. A planetary mill Pulverisatte 7 high energy was used to perform the experiments grinding. Al2O3 powder and Cu in the proportion of 5, 10 and 15% by weight of Cu were placed in a container for grinding with balls of hard metal and ethyl alcohol. A mass ratio of balls to powder of 1:5 was used. All powders were milled to 100 hours, and powder samples were collected after 2, 10, 20, 50 and 70 hours of grinding. Composite powders with compact cylindrical shape of 8 mm diameter were pressed and sintered in uniaxial matrix resistive furnace to 1200, 1300 to 1350 °C for 60 minutes under an atmosphere of argon and hydrogen. The heating rate used was 10°C/min. The powders and structures of the sintered bodies were characterized by XRD, SEM and EDS. Analysis TG, DSC and particle size were also used to characterize the milled powders, as well as dilatometry was used to observe the contraction of the sintered bodies. The density of the green and sintered bodies was measured using the geometric method (mass / volume). Vickers microhardness with a load of 500 g for 10 s were performed on sintered structures. The Cu-Al2O3 composite with 5% copper density reached 61% of theoretical density and a hardness of 129 HV when sintered at 1300 ° C for 1h. In contrast, lower densities (59 and 51% of the theoretical density) and hardness (110 HV and 105) were achieved when the copper content increases to 10 and 15%.

Bi anisotropia em antenas de microfita retangular e estruturas circulares modificadas

The microstrip antennas in your simplest form consist of a ground plane and a dielectric substrate which supports a conductive tape. As these antennas have some limitations, this work presents a study of anisotropic substrates, as well as some results in microstrip antennas with circular patch, aiming to overcome these limitations, especially in applications at 4G technology. These anisotropic substrates are those in which electrical permittivity and magnetic permeability are represented by tensors of second order. The study consists of a theoretical analysis of substrates and development of a mathematical formalism, the Transverse Transmission Line Method, aimed the application of these substrates in microstrip antennas. Among the substrates used in this study, there are the ferrimagnetic and metamaterials, in which some miniaturizations of the antennas are achieved. For antennas with circular patch, are considered arrays and modified ground planes in order to achieve improvement in parameters, in particular, gain and bandwidth. Several simulations have been made and antennas were constructed so that the measured values could be compared with the simulated values.

Plano amostral, ponderação e efeitos do delineamento da Pesquisa Nacional de Saúde Bucal

OBJETIVO: Estimar la prevalencia y la extensión de la caries radicular en la población adulta y anciana de Brasil. MÉTODOS: A partir de los datos de la Investigación Nacional de Salud Bucal (SBBrasil 2010) se examinaron 9.564 adultos y 7.509 ancianos en domicilios de las 26 capitales y en el Distrito Federal y de 150 municipios del interior de cada macro región. Se implementaron criterios de diagnóstico establecidos por la Organización Mundial de la Salud. Para estudio de la prevalencia y de extensión se utilizó el índice de caries radicular y el índice de raíces cariadas y obturadas. RESULTADOS: La prevalencia de caries radicular fue de 16,7% en los adultos y 13,6% en los ancianos; el índice de raíces cariadas y obturadas fue de 0,42 y 0,32 respectivamente, siendo la mayor parte compuesta por caries no tratadas. Se observaron diferencias en la experiencia de caries radicular entre capitales y macro regiones, con valores mayores en capitales del Norte y Noreste. El índice de caries radicular en los adultos varió de 1,4% en Aracaju (SE) a 15,1% en Salvador (BA) y en los ancianos de 3,5% en Porto Velho (RO) a 29,9% en Palmas (TO). Se verificó incremento de caries radicular con la edad y mayor expresividad de la enfermedad en hombres de ambos grupos etarios. CONCLUSIONES: Se identificó una gran variación de la prevalencia y extensión de la caries radicular entre y dentro de las regiones de Brasil, tanto en adultos como en ancianos, y la mayor parte de la caries radicular se encuentra no tratada. Se recomienda la incorporación de este agravio al sistema de vigilancia en salud bucal, debido a su tendencia creciente.

Rudimentos de uma inspeção topográfica aplicados à Passacaglia para orquestra, opus 1, de Anton Webern

SILVA, Alexandre Reche e. Rudimentos de uma inspeção topográfica aplicados à Passacaglia para orquestra, opus 1, de Anton Webern. Ictus - Periódico do PPGMUS/UFBA, Salvador, v. 7, p.189-208, 2010

Efeito da Gália como aditivo de sinterização em eletrólitos cerâmicos à base de céria sintetizados pelo método de complexação de cátions

Fuel cells are considered one of the most promising ways of converting electrical energy due to its high yield and by using hydrogen (as fuel) which is considered one of the most important source of clean energy for the future. Rare earths doped ceria has been widely investigated as an alternative material for the electrolyte of solid oxide fuel cells (SOFCs) due to its high ionic conductivity at low operating temperatures compared with the traditional electrolytes based on stabilized zirconia. This work investigates the effect of gallium oxide (Gallia) as a sintering aid in Eu doped ceria ceramic electrolytes since this effect has already been investigated for Gd, Sm and Y doped ceria electrolytes. The desired goal with the use of a sintering aid is to reduce the sintering temperature aiming to produce dense ceramics. In this study we investigated the effects on densification, microstructure and ionic conduction caused by different molar fraction of the dopants europium (10, 15 and 20%) and gallium oxide (0.3, 0.6 and 0.9%) in samples sintered at 1300, 1350 and 1450 0 C. Samaria (10 and 20%) doped ceria samples sintered between 1350 and 1450 °C were used as reference. Samples were synthesized using the cation complexation method. The ceramics powders were characterized by XRF, XRD and SEM, while the sintered samples were investigated by its relative density, SEM and impedance spectroscopy. It was showed that gallia contents up to 0.6% act as excellent sintering aids in Eu doped ceria. Above this aid content, gallia addition does not promote significant increase in density of the ceramics. In Ga free samples the larger densification were accomplished with Eu 15% molar, effect expressed in the microstructure with higher grain growth although reduced and surrounded by many open pores. Relative densities greater than 95 % were obtained by sintering between 1300 and 1350 °C against the usual range 1500 - 1600 0 C. Samples containing 10% of Sm and 0.9% of Ga reached 96% of theoretical density by sintering at 1350 0 C for 3h, a gain compared to 97% achieved with 20% of Sm and 1% of Ga co-doped cerias sintered at 1450 0 C for 24 h as described in the literature. It is found that the addition of gallia in the Eu doped ceria has a positive effect on the grain conductivity and a negative one in the grain boundary conductivity resulting in a small decrease in the total conductivity which will not compromise its application as sintering aids in ceria based electrolytes. Typical total conductivity values at 600 and 700 °C, around 10 and 30 mS.cm -1 respectively were reached in this study. Samples with 15% of Eu and 0.9 % of Ga sintered at 1300 and 1350 °C showed relative densities greater than 96% and total conductivity (measured at 700 °C) between 20 and 33 mS.cm -1 . The simultaneous sintering of the electrolyte with the anode is one of the goals of research in materials for SOFCs. The results obtained in this study suggest that dense Eu and Ga co-doped ceria electrolytes with good ionic conductivity can be sintered simultaneously with the anode at temperatures below 1350 °C, the usual temperature for firing porous anode materials