10 research outputs found
Comparing communication and development networks for predicting file change proneness: An exploratory study considering process and social metrics
Previous studies have shown that social factors of software engineering influence software quality. Communication and development networks represent the interactions among software developers. We explored the statistical relationships between file change proneness and a set metrics extracted from the issue tracker and version control system data to find the relative importance of each metric inunderstanding the evolution of file changes in the Rails project. Using hierarchical analysis, we found that code churn, number of past changes, and number of developers explain the evolution of changes in the Rails project better than Social NetworkAnalysis (SNA) metrics. Considering the relative importance of each predictor, wegot the same results. We also conducted a factor analysis and found that social metrics contribute to explain a group of files different from those explained by process metrics
Landscape dynamics and diversification of the megadiverse South American freshwater fish fauna
Landscape dynamics are widely thought to govern the tempo and mode of continental radiations, yet the effects of river network rearrangements on dispersal and lineage diversification remain poorly understood. We integrated an unprecedented occurrence dataset of 4,967 species with a newly compiled, time-calibrated phylogeny of South American freshwater fishes—the most species-rich continental vertebrate fauna on Earth—to track the evolutionary processes associated with hydrogeographic events over 100 Ma. Net lineage diversification was heterogeneous through time, across space, and among clades. Five abrupt shifts in net diversification rates occurred during the Paleogene and Miocene (between 30 and 7 Ma) in association with major landscape evolution events. Net diversification accelerated from the Miocene to the Recent (c. 20 to 0 Ma), with Western Amazonia having the highest rates of in situ diversification, which led to it being an important source of species dispersing to other regions. All regional biotic interchanges were associated with documented hydrogeographic events and the formation of biogeographic corridors, including the Early Miocene (c. 23 to 16 Ma) uplift of the Serra do Mar and Serra da Mantiqueira and the Late Miocene (c. 10 Ma) uplift of the Northern Andes and associated formation of the modern transcontinental Amazon River. The combination of high diversification rates and extensive biotic interchange associated with Western Amazonia yielded its extraordinary contemporary richness and phylogenetic endemism. Our results support the hypothesis that landscape dynamics, which shaped the history of drainage basin connections, strongly affected the assembly and diversification of basin-wide fish fauna
A Process for Framework Development from Reverse Engineering of Web-based Information Systems: Application to the Online Auction Domain
Um processo para o desenvolvimento de frameworks para sistemas de informação baseados na Web é proposto. Esse processo é composto pelos subprocessos de engenharia reversa de sistemas baseados na Web, de criação de uma linguagem de padrões e de construção e instanciação do framework. O subprocesso de engenharia reversa utiliza sistemas presentes na Web para derivar um modelo do domínio de aplicação. O desenvolvimento da linguagem de padrões é baseado no modelo do domínio e a construção do framework utiliza essa linguagem de padrões como base de todo o processo. Os produtos resultantes do uso desse processo para o domínio dos leilões virtuais, a Linguagem de Padrões LV e o Framework Qd+, também são apresentados.A process for the development of web-based information systems frameworks is proposed. This process comprises a reverse engineering - for web-based information systems -, a pattern language creation, and a framework instantiation subprocesses. The reverse engineering subprocess uses existing WISs to derive an application domain model. The pattern language is created from the application domain model and the framework is developed from this pattern language. The deliverables of the application of this process to the online auctions domain, the Pattern Language for Online Auctions and the Qd+ Framework, are also presented
A contribution to the minimization of the number of stubs during integration test of aspect-oriented programs
A programação orientada a aspectos é uma abordagem que utiliza conceitos da separação de interesses para modularizar o software de maneira mais adequada. Com o surgimento dessa abordagem vieram também novos desafios, dentre eles o teste de programas orientados a aspectos. Duas estratégias de ordenação de classes e aspectos para apoiar o teste de integração orientado a aspectos são propostas nesta tese. As estratégias de ordenação tem o objetivo de diminuir o custo da atividade de teste por meio da diminuição do número de stubs implementados durante o teste de integração. As estratégias utilizam um modelo de dependências aspectuais e um modelo que descreve dependências entre classes e aspectos denominado AORD (Aspect and Oriented Relation Diagram) também propostos neste trabalho. Tanto o modelo de dependências aspectuais como o AORD foram elaborados a partir da sintaxe e semântica da linguagem AspectJ. Para apoiar as estratégias de ordenação, idealmente aplicadas durante a fase de projeto, um processo de mapeamento de modelos de projeto que usam as notações UML e MATA para o AORD é proposto neste trabalho. O processo de mapeamento é composto de regras que mostram como mapear dependências advindas da programação orientada a objetos e também da programação orientada a aspectos. Como uma forma de validação das estratégias de ordenação, do modelo de dependências aspectuais e do AORD, um estudo exploratório de caracterização com três sistemas implementados em AspectJ foi conduzido. Durante o estudo foram coletadas amostras de casos de implementação de stubs e drivers de teste. Os casos de implementação foram analisados e classificados. A partir dessa análise e classificação, um catálogo de stubs e drivers de teste é apresentadoAspect-oriented programming is an approach that uses principles of separation of concerns to improve the sofware modularization. Testing of aspect-oriented programs is a new challenge related to this approach. Two aspects and classes test order strategies to support integration testing of aspect-oriented programs are proposed in this thesis. The objective of these strategies is to reduce the cost of testing activities through the minimization of the number of implemented stubs during integration test. An aspectual dependency model and a diagram which describes dependencies among classes and aspects called AORD (Aspect and Object Relation Diagram) used by the ordering strategies are also proposed. The aspectual dependency model and the AORD were defined considering the syntax constructions and the semantics of AspectJ. As the proposed estrategies should be applied in design phase of software development, a process to map a desing model using UML and MATA notations into a AORD is proposed in order to support the ordering strategies. The mapping process is composed by rules that show how to map both aspect and object-oriented dependencies. A characterization exploratory study using three systems implemented with AspectJ was conducted to validate the ordering strategies, the aspectual dependency model and the AORD. Interesting samples of stubs implementations were collected during the study conduction. The stubs were analyzed and classified. Based on these analysis and classification a catalog of stubs and drivers is presente
Senso de pertencimento das mulheres em projetos de software
ABSTRACTBackground: Gender diversity is an important feature for softwaredevelopment. Studies show that teams with more diversity are moreproductive, too. Objective: This study is a systematic review thatanalyzes women’s motivations to contribute to software development,focusing on a sense of belonging. Method: A protocol wasestablished and the works retrieved by the applied search string.It was analyzed according to the inclusion and exclusion criteria.Results: The results showed that the main factors that motivatewomen to contribute to software projects are Kinship, Career andLearning. However, the sense of belonging, related to the termKinship, was more important in the analysis of groups composedonly of women, compared to heterogeneous groups. Conclusions:Thus, it was found that there are differences in motivations betweengenders, and the sense of belonging is more relevant forwomen than for men. Therefore, to increase diversity in softwareprojects, an important factor to be improved is the belonging of thecontributors