Uma abordagem anotativa para gerência de variabilidade em linhas de processos de software: concepção, implementação e avaliação

Nowadays, the importance of using software processes is already consolidated and is considered fundamental to the success of software development projects. Large and medium software projects demand the definition and continuous improvement of software processes in order to promote the productive development of high-quality software. Customizing and evolving existing software processes to address the variety of scenarios, technologies, culture and scale is a recurrent challenge required by the software industry. It involves the adaptation of software process models for the reality of their projects. Besides, it must also promote the reuse of past experiences in the definition and development of software processes for the new projects. The adequate management and execution of software processes can bring a better quality and productivity to the produced software systems. This work aimed to explore the use and adaptation of consolidated software product lines techniques to promote the management of the variabilities of software process families. In order to achieve this aim: (i) a systematic literature review is conducted to identify and characterize variability management approaches for software processes; (ii) an annotative approach for the variability management of software process lines is proposed and developed; and finally (iii) empirical studies and a controlled experiment assess and compare the proposed annotative approach against a compositional one. One study a comparative qualitative study analyzed the annotative and compositional approaches from different perspectives, such as: modularity, traceability, error detection, granularity, uniformity, adoption, and systematic variability management. Another study a comparative quantitative study has considered internal attributes of the specification of software process lines, such as modularity, size and complexity. Finally, the last study a controlled experiment evaluated the effort to use and the understandability of the investigated approaches when modeling and evolving specifications of software process lines. The studies bring evidences of several benefits of the annotative approach, and the potential of integration with the compositional approach, to assist the variability management of software process lines

Análise de impacto baseada em rastreabilidade de artefatos para linhas de produto de software

Software Product Line (SPL) consists of a software development paradigm, whose main focus is to identify features common and variability among applications in a specific domain. An LPS is designed to attend all products requirements from its product family. These requirements and LPS may have changes over time due to several factors, such as evolution of product requirements, evolution of the market, evolution of SLP process, evolution of the technologies used to develop the products. To handle these changes, LPS should be modified and evolve in order to not become obsolete, and adapt itself to new requirements. The Changes Impact Analysis is an activity that understand and identify what consequences these changes are cause on LPS. Impact Analysis on LPS may be supported by traceability relationships, which identify relationships between artefacts created during all phases of software development. Despite the solutions of change impact analysis based on traceability for software, there is a lack of solutions for assessing the change impact analysis based on traceability for LPS, since existing solutions do not include estimates specific to the artefacts of LPS. Thus, this paper proposes a process of change impact analysis and an tool for assessing the change impact through traceability of artefacts in LPS. For this purpose, we specified a process of change impact analysis that considers artifacts produced during the development of LPS. We have also implemented a tool which allows estimating and identifying artefacts and products of LPS affected from changes in other products, changes in class, changes in features, changes between releases of LPS and artefacts related to changes in core assets and variability. Finally, the results were evaluated through metrics

Uma abordagem sistemática para implementação, gerenciamento e customização de testes de linhas de produto de software

Through the adoption of the software product line (SPL) approach, several benefits are achieved when compared to the conventional development processes that are based on creating a single software system at a time. The process of developing a SPL differs from traditional software construction, since it has two essential phases: the domain engineering - when common and variables elements of the SPL are defined and implemented; and the application engineering - when one or more applications (specific products) are derived from the reuse of artifacts created in the domain engineering. The test activity is also fundamental and aims to detect defects in the artifacts produced in SPL development. However, the characteristics of an SPL bring new challenges to this activity that must be considered. Several approaches have been recently proposed for the testing process of product lines, but they have been shown limited and have only provided general guidelines. In addition, there is also a lack of tools to support the variability management and customization of automated case tests for SPLs. In this context, this dissertation has the goal of proposing a systematic approach to software product line testing. The approach offers: (i) automated SPL test strategies to be applied in the domain and application engineering, (ii) explicit guidelines to support the implementation and reuse of automated test cases at the unit, integration and system levels in domain and application engineering; and (iii) tooling support for automating the variability management and customization of test cases. The approach is evaluated through its application in a software product line for web systems. The results of this work have shown that the proposed approach can help the developers to deal with the challenges imposed by the characteristics of SPLs during the testing process

Dos requisitos à arquitetura em linhas de produtos de software: uma estratégia de transformações entre modelos

The tracking between models of the requirements and architecture activities is a strategy that aims to prevent loss of information, reducing the gap between these two initial activities of the software life cycle. In the context of Software Product Lines (SPL), it is important to have this support, which allows the correspondence between this two activities, with management of variability. In order to address this issue, this paper presents a process of bidirectional mapping, defining transformation rules between elements of a goaloriented requirements model (described in PL-AOVgraph) and elements of an architectural description (defined in PL-AspectualACME). These mapping rules are evaluated using a case study: the GingaForAll LPS. To automate this transformation, we developed the MaRiPLA tool (Mapping Requirements to Product Line Architecture), through MDD techniques (Modeldriven Development), including Atlas Transformation Language (ATL) with specification of Ecore metamodels jointly with Xtext , a DSL definition framework, and Acceleo, a code generation tool, in Eclipse environment. Finally, the generated models are evaluated based on quality attributes such as variability, derivability, reusability, correctness, traceability, completeness, evolvability and maintainability, extracted from the CAFÉ Quality Model

Reqsys-MDD: uma ferramenta para mapeamento entre modelos de features e requisitos em linhas de produto de software

The approach Software Product Line (SPL) has become very promising these days, since it allows the production of customized systems on large scale through product families. For the modeling of these families the Features Model is being widely used, however, it is a model that has low level of detail and not may be sufficient to guide the development team of LPS. Thus, it is recommended add the Features Model to other models representing the system from other perspectives. The goals model PL-AOVgraph can assume this role complementary to the Features Model, since it has a to context oriented language of LPS's, which allows the requirements modeling in detail and identification of crosscutting concerns that may arise as result of variability. In order to insert PL-AOVgraph in development of LPS's, this paper proposes a bi-directional mapping between PL-AOVgraph and Features Model, which will be automated by tool ReqSys-MDD. This tool uses the approach of Model-Driven Development (MDD), which allows the construction of systems from high level models through successive transformations. This enables the integration of ReqSys-MDD with other tools MDD that use their output models as input to other transformations. So it is possible keep consistency among the models involved, avoiding loss of informations on transitions between stages of development

Caracterizando os fluxos excepcionais em linhas de produto de software: um estudo exploratório

The Exception Handling (EH) is a widely used mechanism for building robust systems. In Software Product Line (SPL) context it is not different. As EH mechanisms are embedded in most of mainstream programming languages (like Java, C# and C++), we can find exception signalers and handlers spread over code assets associated to common and variable SPL features. When exception signalers and handlers are added to an SPL in an unplanned way, one of the possible consequences is the generation of faulty family instances (i.e., instances on which common or variable features signal exceptions that are mistakenly caught inside the system). In this context, some questions arise: How exceptions flow between the optional and alternative features an LPS? Aiming at providing answers to these questions, this master thesis conducted an exploratory study, based on code inspection and static analysis code, whose goal was to categorize the main ways which exceptions flow in LPSs. To support the study, we developed an static analysis tool called PLEA (Product Line Exception Analyzer) that calculates the exceptional flows of LPSs, and categorize these flows according to the features associated with handlers and signalers. Preliminary results showed that some types of exceptional flows have more potential to yield failures in exceptional behavior of SLPs

Squid impact analyser: uma ferramenta para análise de impacto de mudança em linhas de produto de software

Software Products Lines (SPL) is a software engineering approach to developing software system families that share common features and differ in other features according to the requested software systems. The adoption of the SPL approach can promote several benefits such as cost reduction, product quality, productivity, and time to market. On the other hand, the SPL approach brings new challenges to the software evolution that must be considered. Recent research work has explored and proposed automated approaches based on code analysis and traceability techniques for change impact analysis in the context of SPL development. There are existing limitations concerning these approaches such as the customization of the analysis functionalities to address different strategies for change impact analysis, and the change impact analysis of fine-grained variability. This dissertation proposes a change impact analysis tool for SPL development, called Squid Impact Analyzer. The tool allows the implementation of change impact analysis based on information from variability modeling, mapping of variability to code assets, and existing dependency relationships between code assets. An assessment of the tool is conducted through an experiment that compare the change impact analysis results provided by the tool with real changes applied to several evolution releases from a SPL for media management in mobile devices

Localização de faltas em linhas de transmissão usando morfologia matemática

This work an algorithm for fault location is proposed. It contains the following functions: fault detection, fault classification and fault location. Mathematical Morphology is used to process currents obtained in the monitored terminals. Unlike Fourier and Wavelet transforms that are usually applied to fault location, the Mathematical Morphology is a non-linear operation that uses only basic operation (sum, subtraction, maximum and minimum). Thus, Mathematical Morphology is computationally very efficient. For detection and classification functions, the Morphological Wavelet was used. On fault location module the Multiresolution Morphological Gradient was used to detect the traveling waves and their polarities. Hence, recorded the arrival in the two first traveling waves incident at the measured terminal and knowing the velocity of propagation, pinpoint the fault location can be estimated. The algorithm was applied in a 440 kV power transmission system, simulated on ATP. Several fault conditions where studied and the following parameters were evaluated: fault location, fault type, fault resistance, fault inception angle, noise level and sampling rate. The results show that the application of Mathematical Morphology in faults location is very promising

Produtividade de alface e rabanete em cultivo consorciado estabelecido em diferentes épocas e espaçamentos entre linhas

O trabalho foi conduzido na UNESP, Jaboticabal-SP, de maio a agosto de 2001, com objetivo de avaliar a produtividade de alface e rabanete em função do espaçamento e da época de estabelecimento do consórcio. Os 14 tratamentos foram avaliados em blocos ao acaso, com quatro repetições e parcelas de 20 plantas, sendo resultado da combinação dos fatores espaçamento entre linhas da alface (0,3 e 0,4 m), sistemas de cultivo (consórcio e monocultivo) e época de semeadura do rabanete (0; 7 e 14 dias após o transplantio da alface). As cultivares utilizadas foram Tainá (alface) e Crimson Gigante (rabanete). Devido ao estande mais elevado, a produtividade do rabanete em monocultivo foi superior à melhor produtividade obtida em consórcio. Porém, quando se avaliou a produtividade em g m-1, o melhor resultado (518,8 g m-1) foi observado em cultivo consorciado com semeadura do rabanete 14 dias após o transplantio de alface (DAT), sendo significativamente superior à produtividade obtida no monocultivo. Observou-se ainda incremento significativo na produtividade de raízes comerciais de rabanete à medida em que se atrasou o estabelecimento do consórcio. O espaçamento da alface não influenciou significativamente a massa fresca da parte aérea (MFPA) das plantas das laterais do canteiro. Entretanto, houve redução significativa na MFPA das plantas internas ao canteiro quando o espaçamento entre linhas foi reduzido de 0,40 (460,3 g) para 0,30 m (321,1 g). A MFPA de plantas de alface cultivadas em consórcio e situadas nas duas linhas centrais do canteiro (MFPAIn = 434,9 g) não diferiu significativamente da obtida em monocultivo (542,9 g) quando as culturas foram implantadas na mesma data. O mesmo foi observado para plantas situadas nas laterais do canteiro (MFPAEx = 529,2 g), quando o consórcio foi estabelecido até 7 DAT da alface. em consórcios estabelecidos a partir desta época, a produção de alface foi sempre menor que em monocultivo. Independente do espaçamento entre linhas e do tempo de semeadura do rabanete em relação ao transplantio da alface, todos os índices de Uso Eficiente da Terra (UET) foram maiores que 1,0.

Ambigüidade gerada pela homonímia: revisitação teórica, linhas limítrofes com a polissemia e proposta de critérios distintivos

O presente trabalho almeja expor o fenômeno da homonímia no português do Brasil, enquanto ambigüidade presente em uma língua natural, por meio de uma revisitação teórica em diversos autores e em confronto com a polissemia. Ademais, pretende-se, além de redefinir conceitualmente a homonímia, propor critérios semânticos distintivos para esse fenômeno lingüístico, tais como a análise sêmica, o campo léxico, o uso de expressões cristalizadas e a ocorrência de traços especificadores.

População de plantas e espaçamento entre linhas do feijoeiro irrigado. I: comportamento morfológico das plantas

O experimento foi conduzido com o objetivo de avaliar variações no índice de área foliar, altura das plantas, número de nós, comprimento dos entrenós na haste principal e altura das vagens em relação à superfície do solo do feijoeiro irrigado e cultivado em diferentes populações de plantas e espaçamentos entre linhas de cultivo. O experimento foi conduzido no ano agrícola 1997/98, em área experimental do Departamento de Engenharia Rural da Universidade Federal de Santa Maria (UFSM), Santa Maria, RS. A cultivar de feijão preto BR-FEPAGRO 44 - Guapo brilhante, de crescimento indeterminado (tipo II), foi cultivada em três populações de plantas (175, 250 e 325 mil plantas há-1) e três espaçamentos entre linhas de cultivo (35, 50 e 65cm). Utilizou-se o delineamento experimental inteiramente casualizado, bifatorial, com quatro repetições. Irrigações por aspersão foram aplicadas quando a evapotranspiração máxima da cultura, estimada com base na evaporação do tanque classe A, indicava um valor acumulado de 25mm. Os resultados demonstraram que o aumento da população de plantas ocasionou aumento no índice de área foliar durante a fase de crescimento vegetativo da cultura, sendo que na fase reprodutiva, o índice de área foliar foi afetado pelo espaçamento entre as linhas de cultivo. A área foliar, a altura de plantas e o número de nós na haste principal aumentaram com a redução na população de plantas. A altura da extremidade da primeira vagem das plantas em relação ao solo apresentou comportamento quadrático com o aumento na população de plantas. Os diferentes espaçamentos e populações de plantas não afetaram o comprimento dos entrenós na haste principal das plantas.

População de plantas e espaçamento entre linhas do feijoeiro irrigado. II: rendimento de grãos e componentes do rendimento

O objetivo deste experimento foi avaliar o efeito de diferentes populações de plantas e espaçamentos entre linhas de cultivo na produção de massa seca, rendimento de grãos e componentes do rendimento da cultura do feijoeiro irrigado. O experimento foi conduzido no ano agrícola 1997/1998, em área do Departamento de Engenharia Rural da Universidade Federal de Santa Maria (UFSM), RS. A cultivar de feijão preto BR-FEPAGRO 44 - Guapo brilhante, habito de crescimento indeterminado (tipo II), foi submetida a três populações de plantas (175, 250 e 325 mil plantas há-1) e três espaçamentos entre linhas de cultivo (35, 50 e 65cm). Utilizou-se o delineamento experimental inteiramente casualizado, bifatorial, com quatro repetições. Irrigações por aspersão foram aplicadas quando a evapotranspiração máxima da cultura, estimada a partir da evaporação do tanque classe A, indicava um valor acumulado de 25mm. Os resultados demonstraram que as diferentes populações de plantas e espaçamentos entre linhas de cultivo não ocasionaram alterações no rendimento de grãos e massa de mil sementes. No entanto, o número de sementes por vagem e de vagens por planta aumentaram com a redução na população de plantas. Na fase do enchimento de grãos, a redução do espaçamento entre linhas de cultivo aumentou a massa seca da parte aérea das plantas. A cultivar de feijoeiro, BR-FEPAGRO 44 - Guapo brilhante, apresenta elevada plasticidade dos componentes do rendimento, havendo compensação no rendimento de grãos nas menores populações de plantas com aumento da produção por planta.

Conchostráceos com linhas de crescimento recurvadas junto à margem dorsal (famílias Palaeolimnadiopseidae e Perilimnadiidae) da formação rio do rasto, Permiano superior, bacia do Paraná, Brasil

Some Upper Permian conchostracans from the Rio do Rasto Formation (Parana Basin, South Brazil) have very characteristic recurved growth lines at the dorsal margin. All previously described specimens were classified as Palaeolimnadiopsis subalata (Reed) Raymond. However, a re-analysis of these fossils and of additional recently- collected specimens demonstrated that not all can be included in a single species, nor only in the Family Palaeolimnadiopseidae. According to their shape and the size of the umbo, they are classified into three species. The sub-elliptic carapaces with small anterior umbo are maintained in Palaeolimnadiopsis subalata (Reed, 1929) Raymond, 1946. The sub-circular carapaces with small sub-central umbo correspond to the new species Palaeolimnadiopsis riorastensis. The small size of the umbo is a character of the Family Palaeolimnadiopseidae. The small elliptic valves with large anterior umbo are assigned to the new species Falsisca brasiliensis of the Family Perilimnadiidae, which is characterized by large umbos. Palaeolimnadiopsis has a wide chronostratigraphic distribution, but Falsisca is restricted to the Upper Permian-Lower Triassic of Europe and Asia. This interval is in agreement with the probable Late Permian age of the respective strata of the Rio do Rasto formation. Falsisca was not previously recorded in Gondwana.

Conchostráceos com linhas de crescimento recurvadas junto à margem dorsal (Famílias Palaeolimnadiopseidae e Perilimnadiidae) da Formação Rio do Rasto, permiano superior, Bacia do Paraná, Brasil

Some Upper Permian conchostracans from the Rio do Rasto Formation (Paraná Basin, South Brazil) have very characteristic recurved growth lines at the dorsal margin. All previously described specimens were classified as Palaeolimnadiopsis subalata (Reed) Raymond. However, a re-analysis of these fossils and of additional recently- collected specimens demonstrated that not all can be included in a single species, nor only in the Family Palaeolimnadiopseidae. According to their shape and the size of the umbo, they are classified into three species. The sub-elliptic carapaces with small anterior umbo are maintained in Palaeolimnadiopsis subalata (Reed, 1929) Raymond, 1946. The sub-circular carapaces with small sub-central umbo correspond to the new species Palaeolimnadiopsis riorastensis. The small size of the umbo is a character of the Family Palaeolimnadiopseidae. The small elliptic valves with large anterior umbo are assigned to the new species Falsisca brasiliensis of the Family Perilimnadiidae, which is characterized by large umbos. Palaeolimnadiopsis has a wide chronostratigraphic distribution, but Falsisca is restricted to the Upper Permian-Lower Triassic of Europe and Asia. This interval is in agreement with the probable Late Permian age of the respective strata of the Rio do Rasto Formation. Falsisca was not previously recorded in Gondwana.

Extração de vias combinando métodos de detecção de regiões e linhas em imagens de intensidade de pulso laser

This paper aims at extracting street centerlines from previously isolated street regions by using the image of laser scanning intensity. In this image, streets are easily identified, since they manifest as dark, elongate ribbons contrasting with background objects. The intensity image is segmented by using the region growing technique, which generates regions representing the streets. From these regions, the street centerlines are extracted in two manners. The first one is through the Steger lines detection method combined with a line length thresholding by which lines being shorter than a minimum length are removed. The other manner is by combining the skeletonization method of regions based on the Medial Axis Transform and with a pruning process to eliminate as much as possible the ramifications. Experiments showed that the Steger-based method provided results better than the method based on skeletonization.