Highlighting model elements to improve OCL comprehension

Models, metamodels, and model transformations play a central role in Model-Driven Development (MDD). Object Constraint Language (OCL) was initially proposed as part of the Unified Modeling Language (UML) standard to add the precision and validation capabilities lacking in its diagrams, and to express well-formedness rules in its metamodel. OCL has several other applications, such as defining design metrics, code-generation templates, or validation rules for model transformations, required in MDD. Learning OCL as part of a UML course at the university would seem natural but is still the exception rather than the rule. We believe that this is mainly due to a widespread perception that OCL is hard to learn, as gleaned from claims made in the literature. Based on data gathered over the past school years from numerous undergraduate students of di↵erent Software Engineering courses, we analyzed how learning design by contract clauses with UML+OCL compares with several other Software Engineering Body Of Knowledge (SWEBOK) topics. The outcome of the learning process was collected in a rigorous setup, supported by an e-learning platform. We performed inferential statistics on that data to support our conclusions and identify the relevant explanatory variables for students’ success/failure. The obtained findings lead us to extend an existing OCL tool with two novel features: one is aimed at OCL apprentices and goes straight to the heart of the matter by allowing to visualize how OCL expressions traverse UML class diagrams; the other is intended for researchers and allows to compute OCL complexity metrics, making it possible to replicate a research study like the one we are presenting.Modelos, metamodelos e transformações de modelo desempenham um papel central em MDD. OCL foi inicialmente proposta como parte da UML para adicionar os recursos de precisão e validação que faltavam nestes diagramas, e também para expressar regras de boa formação no metamodelo. OCL possui outras aplicações, tais como definir métricas de desenho, modelos de geração de código ou regras de validação para transformações de modelo, exigidas em MDD. Aprender OCL como parte de um curso de UML na universidade parecia portanto natural, não sendo no entanto o que se verifica. Acreditamos que isso se deva a uma percepção generalizada de que OCL é difícil de aprender, tendo em conta afirmações feitas na literatura. Com base em dados recolhidos em anos letivos anteriores de vários alunos de licenciatura de diferentes cursos de Engenharia de Software, analisámos como a aprendizagem por cláusulas contratuais de UML + OCL se compara a outros tópicos do SWEBOK. O resultado do processo de aprendizagem foi recolhido de forma rigorosa, apoiado por uma plataforma de e-learning. Realizámos estatísticas inferenciais sobre os dados para apoiar as nossas conclusões, de forma a identificar as variáveis explicativas relevantes para o sucesso / fracasso dos alunos. As conclusões obtidas levaram-nos a estender uma ferramenta OCL com duas novas funcionalidades: a primeira é voltada para os estudantes de OCL e permite visualizar como as expressões percorrem um diagrama de classes UML; a segunda é voltada para investigadores e permite calcular métricas de complexidade OCL, habilitando a réplica de um estudo semelhante ao apresentado

Data access and integration in the ISPIDER proteomics grid

Grid computing has great potential for supporting the integration of complex, fast changing biological data repositories to enable distributed data analysis. One scenario where Grid computing has such potential is provided by proteomics resources which are rapidly being developed with the emergence of affordable, reliable methods to study the proteome. The protein identifications arising from these methods derive from multiple repositories which need to be integrated to enable uniform access to them. A number of technologies exist which enable these resources to be accessed in a Grid environment, but the independent development of these resources means that significant data integration challenges, such as heterogeneity and schema evolution, have to be met. This paper presents an architecture which supports the combined use of Grid data access (OGSA-DAI), Grid distributed querying (OGSA-DQP) and data integration (AutoMed) software tools to support distributed data analysis. We discuss the application of this architecture for the integration of several autonomous proteomics data resources

Functional linguistic perspectives in TESOL: Curriculum design and text-based instruction

This paper outlines the general influence of Halliday’s (1994, 2014) systemic functional linguistics on TESOL curriculum. Halliday’s explanation of language as a social semiotic and language learning as learning to mean has been applied internationally in genre and text- based teaching. The concept of register in systemic functional linguistics describes linguistic variation of texts for the expression of different meanings. SFL studies document teachers’ explicit instruction in the lexicogrammatical construction of text types linked to function and social context. The explicitness informs students’ decision-making for formulation of meanings in different text types. Reference is made to SFL applied in teacher education. There is mention of the relevance of SFL to Australia’s concern with literacy standards in education

Bye-bye mummy: word comprehension in 9-month-old infants

From the little research that exists on the onset of word learning in infants under the age of 1 year, the evidence suggests an idiosyncratic comprehensive vocabulary is developing. To further this field, we tested 49 nine-month-old infants by pre-assessing their vocabularies using a UK version of the MacArthur-Bates Communicative Developmental Inventory. Intermodal preferential looking (IPL) was then used to examine word comprehension including: (a) words parents reported as understood, (b) words infants are expected to understand according to age-related frequency data, and (c) words parents had reported infants not to understand. Assuming parents are good assessors of their infant's early word knowledge, we expected a naming effect with IPL in condition (a), but not condition (c). As language research uses standard samples of words, we expected a discernible naming effect in condition (b). Results show clear IPL evidence of word comprehension for those words that parents reported their infants to understand (condition a). This agreement between methods demonstrates the usefulness of parental communicative developmental inventory in conjunction with IPL to assess infant's individual word knowledge. No naming effects were found for condition (c) and the lack of naming effects in (b) shows that pre-established word lists may not give a sufficiently clear picture of infant's true vocabulary – an important insight for researchers and practitioners alike