Abstract
Lenses are one of the most popular approaches to define bidirectional transformations between data models. However, writing a lens transformation typically implies describing the concrete steps that convert values in a source schema to values in a target schema. In contrast, many XML-based languages allow writing structure-shy programs that manipulate only specific parts of XML documents without having to specify the behavior for the remaining structure. In this paper, we propose a structure-shy bidirectional two-level transformation language for XML Schemas, that describes generic type-level transformations over schema representations coupled with value-level bidirectional lenses for document migration. When applying these two-level programs to particular schemas, we employ an existing algebraic rewrite system to optimize the automatically-generated lens transformations, and compile them into Haskell bidirectional executables. We discuss particular examples involving the generic evolution of recursive XML Schemas, and compare their performance gains over non-optimized definitions. © 2012 Springer-Verlag.

Abstract

Abstract
Many of the current approaches used in teaching and learning in engineering education are not the most appropriate to prepare students for the challenges they will face in their professional careers. The active involvement of students in their learning process facilitates the development of the technical and professional competencies they need as professionals. This article describes the organisation and impact of a mini-conference and project work - the creation of a software product and its introduction in the market - aimed at the development of professional competencies in general and writing skills in particular. The course was evaluated by assessing the students' perception of the development of a number of professional competencies through a questionnaire completed by 125 students from two consecutive year groups. The results indicate that the project work and the mini-conference had a positive impact on students' perceptions of the development of professional competencies. © 2012 Copyright SEFI.

Abstract

Abstract

Abstract
Since wireless sensor network applications are ever growing in scale and complexity, managers require strong formal guarantees that any changes done to the system can be enacted safely. This paper presents the formalisation and analysis of the semantics of policies, tiny software artefacts used to orchestrate wireless sensor network applications. The semantics of policies is formalised in terms of traces augmented with information concerning the constraints under which traces are executed. These traces are composed according to the network topology and subsequently analysed using the mCRL2 model-checking tool. The analysis allows for the detection of semantical inconsistencies that may lead to dangerous or unwanted behaviour of the application based on the policy configuration. An analysis of policies in a real-world system is provided, showing how to verify security and resource usage properties. © 2012 IEEE.