Especificação do micronúcleo FreeRTOS utilizando o método B

This paper presents a contribution to the international Verified Software Repository effort through the formal specification of the microkernel FreeRTOS real-time system. Such specification was made in abstract level making use of the B method . For thus, properties of the microkernel were chosen and selected as specification requisites, which was constructed centered at the functionalities responsible for the utilization of these properties. This properties weres setting as specification requirements. The specification was constructed modeling the function of microkernel that implement this properties. This work intended to encourage the formal verification of FreeRTOS and also contribute to the formal creation of a microkernel real-time systems, based in FreeRTOS. Furthermore, this model brings a formal documentation point view of the microkernel, demonstrating features and how this internal states is changing. Finally, this work could be an example of specification of the actual system by the B method.

KitSmart: Uma biblioteca de componentes para o desenvolvimento rigoroso de aplicações Java Card com o método B

The development of smart card applications requires a high level of reliability. Formal methods provide means for this reliability to be achieved. The BSmart method and tool contribute to the development of smart card applications with the support of the B method, generating Java Card code from B specifications. For the development with BSmart to be effectively rigorous without overloading the user it is important to have a library of reusable components built in B. The goal of KitSmart is to provide this support. A first research about the composition of this library was a graduation work from Universidade Federal do Rio Grande do Norte, made by Thiago Dutra in 2006. This first version of the kit resulted in a specification of Java Card primitive types byte, short and boolean in B and the creation of reusable components for application development. This work provides an improvement of KitSmart with the addition of API Java Card specification made in B and a guide for the creation of new components. The API Java Card in B, besides being available to be used for development of applications, is also useful as a documentation of each API class. The reusable components correspond to modules to manipulate specific structures, such as date and time. These structures are not available for B or Java Card. These components for Java Card are generated from specifications formally verified in B. The guide contains quick reference on how to specify some structures and how some situations were adapted from object-orientation to the B Method. This work was evaluated through a case study made through the BSmart tool, that makes use of the KitSmart library. In this case study, it is possible to see the contribution of the components in a B specification. This kit should be useful for B method users and Java Card application developers

Um método para desenvolvimento de abordagens generativas com composição de linguagens específicas de domínio

The software systems development with domain-specific languages has become increasingly common. Domain-specific languages (DSLs) provide increased of the domain expressiveness, raising the abstraction level by facilitating the generation of models or low-level source code, thus increasing the productivity of systems development. Consequently, methods for the development of software product lines and software system families have also proposed the adoption of domain-specific languages. Recent studies have investigated the limitations of feature model expressiveness and proposing the use of DSLs as a complement or substitute for feature model. However, in complex projects, a single DSL is often insufficient to represent the different views and perspectives of development, being necessary to work with multiple DSLs. In order to address new challenges in this context, such as the management of consistency between DSLs, and the need to methods and tools that support the development with multiple DSLs, over the past years, several approaches have been proposed for the development of generative approaches. However, none of them considers matters relating to the composition of DSLs. Thus, with the aim to address this problem, the main objectives of this dissertation are: (i) to investigate the adoption of the integrated use of feature models and DSLs during the domain and application engineering of the development of generative approaches; (ii) to propose a method for the development of generative approaches with composition DSLs; and (iii) to investigate and evaluate the usage of modern technology based on models driven engineering to implement strategies of integration between feature models and composition of DSLs

Estudo mecânico da estabilidade dorsal da osteossíntese intramedular associada à fixação externa (método de Ulson)

OBJETIVO: Avaliar o método de Ulson de fixação intramedular associado à fixação externa variando a altura do travamento externo dos fios de Kirschner e sem fixação externa. MÉTODO: Foram utilizadas 18 tíbias de porcos, sendo realizada osteotomia transversal na região da tuberosidade e introduzidos dois fios de Kirschner intramedulares em cada peça, em três diferentes padrões de montagem: grupo I - travamento com minifixador externo com 3,0cm de altura; grupo II - travamento com 4,5cm de altura; grupo III: sem travamento externo. Realizaram-se ensaios mecânicos de cisalhamento, obtendo-se: carga máxima, limite de proporcionalidade e coeficiente de rigidez. RESULTADOS: Não foram encontradas diferenças significativas de carga máxima e limite de proporcionalidade entre os grupos; o grupo II apresentou maior coeficiente de rigidez. CONCLUSÃO: A altura do travamento dos fios de Kirschner no método de Ulson, dentro dos limites avaliados, não prejudicou a estabilidade do sistema de fixação da fratura.

Um método semi-automatizado para elicitação de requisitos de acessibilidade Web

In the context of Software Engineering, web accessibility is gaining more room, establishing itself as an important quality attribute. This fact is due to initiatives of institutions such as the W3C (World Wide Web Consortium) and the introduction of norms and laws such as Section 508 that underlie the importance of developing accessible Web sites and applications. Despite these improvements, the lack of web accessibility is still a persistent problem, and could be related to the moment or phase in which this requirement is solved within the development process. From the moment when Web accessibility is generally regarded as a programming problem or treated when the application is already developed entirely. Thus, consider accessibility already during activities of analysis and requirements specification shows itself a strategy to facilitate project progress, avoiding rework in advanced phases of software development because of possible errors, or omissions in the elicitation. The objective of this research is to develop a method and a tool to support requirements elicitation of web accessibility. The strategy for the requirements elicitation of this method is grounded by the Goal-Oriented approach NFR Framework and the use of catalogs NFRs, created based on the guidelines contained in WCAG 2.0 (Web Content Accessibility Guideline) proposed by W3C

Método e sociologia em Weber: alguns conceitos fundamentais

Os parâmetros de análise social fornecidos pelos fundamentos da obra weberiana apontam algumas determinações necessárias à análise de fenômenos sociais. Defendendo uma sociologia capaz de compreender os sentidos e conexões presentes nas ações sociais, Weber propõe uma concepção específica de método e de objeto na sociologia, que se assenta na explicação de ações sociais individuais, sob condições determinadas, e busca, ao mesmo tempo, explicitar as significações das instituições sociais, nas quais os indivíduos agem, como resultantes também da ação humana. A partir de tais idéias, o breve ensaio ora apresentado, propõe-se a debater alguns elementos trabalhados nos conceitos weberianos de método e sociologia

Síntese e caracterização de pós Ba(x)Sr(1-x)Co0,8Fe0,2O3- através do método de coprecipitação via oxalato

Ceramic powders based on oxides of perovskite-type structure is of fundamental interest nowadays, since they have important ionic-electronic conductivity in the use of materials with technological applications such as gas sensors, oxygen permeation membranes, catalysts and electrolytes for solid oxide fuel cells (SOFC). The main objective of the project is to develop nanostructured ceramic compounds quaternary-based oxide Barium (Br), Strontium (Sr), Cobalt (Co) and Iron (Fe). In this project were synthesized compounds BaxSr(1-x)Co0, 8Fe0,2O3- (x = 0.2, 0.5 and 0.8) through the oxalate co-precipitation method. The synthesized powders were characterized by thermogravimetric analysis and differential thermal analysis (TGADTA), X-ray diffraction (XRD) with the Rietveld refinement using the software MAUD and scanning electron microscopy (SEM). The results showed that the synthesis technique used was suitable for production of nanostructured ceramic solid solutions. The powders obtained had a crystalline phase with perovskite-type structure. The TGA-DTA results showed that the homogeneous phase of interest was obtained temperature above 1034°C. It was also observed that the heating rate of the calcination process did not affect the elimination of impurities present in the ceramic powder. The variation in the addition of barium dopant promoted changes in the average crystallite size in the nanometer range, the composition being BSCF(5582) obtained the lowest value (179.0nm). The results obtained by oxalate co-precipitation method were compared with those synthesis methods in solid state and EDTA-citrate method

Método de Projeções Ortogonais

The problem treated in this dissertation is to establish boundedness for the iterates of an iterative algorithm in dexed in a (possibly infinite) family of lines, allowing arbitrary order in applying the projections. This problem was analyzed in a paper by Barany et al. in 1994, which found a necessary and suficient condition in the case d = 2, and analyzed further the case d > 2, under some technical conditions. However, this paper uses non-trivial intuitive arguments and its proofs lack suficient rigor. In this dissertation we discuss and strengthen the results of this paper, in order to complete and simplify its proofs