An effective requirements engineering (RE) approach must harmonise the need to achieve separation of concerns with the need to satisfy broadly scoped requirements and constraints. Techniques such as use cases and viewpoints help achieve separation of stakeholders' concerns but ensuring their consistency with global requirements and constraints is largely unsupported. In this paper we propose an approach to modularise and compose such crosscutting, aspectual requirements. The approach is based on separating the specification of aspectual requirements, non-aspectual requirements and composition rules in modules representing coherent abstractions and following welldefined templates. The composition rules employ informal, and often concern-specific, actions and operators to specify how an aspectual requirement influences or constrains the behaviour of a set of non-aspectual requirements. We argue that such modularisation makes it possible to establish early trade-offs between aspectual requirements hence providing support for negotiation and subsequent decision-making among stakeholders. At the same time early separation of crosscutting requirements facilitates determination of their mapping and influence on artefacts at later development stages. A realisation of the proposed approach, based on viewpoints and the eXtensible Markup Language (XML), supported by a tool called ARCaDe and a case study of a toll collection system is presented

Aspect-oriented software development has focused on the software life cycle's implementation phase: developers identify and capture aspects mainly in code. But aspects are evident earlier in the life cycle, such as during requirements engineering and architecture design. Early aspects are concerns that crosscut an artifact's dominant decomposition or base modules derived from the dominant separation-of-concerns criterion, in the early stages of the software life cycle. In this article, we describe how to identify and capture early aspects in requirements and architecture activities and how they're carried over from one phase to another. We'll focus on requirements and architecture design activities to illustrate the points, but the same ideas apply in other phases as well, such as domain analysis or in the fine-grained design activities that lie between architecture and implementation

Effective RE must reconcile the need to achieve separation of concerns with the need to satisfy broadly scoped requirements and constraints. Techniques such as use cases and viewpoints help achieve separation of stakeholders' concerns but ensuring their consistency with global requirements and constraints is largely unsupported. We build on recent work that has emerged from the aspect-oriented programming (AOP) community to propose a general model for aspect oriented requirements engineering (AORE). The model supports separation of crosscutting functional and non-functional properties at the requirements level. We argue that early separation of such crosscutting properties supports effective determination of their mapping and influence on artefacts at later development stages. A realisation of the model based on a case study of a toll collection system is presented.

Research shows that the global society as organized today, with our current technological and economic system, is impossible to sustain. We are living in an era in which human activities in highly industrialized countries are responsible for overshooting several planetary boundaries, with poorer communities contributing the least to the problems but being impacted the most. At the same time, technical and economic gains fail to provide society at large with equal opportunities and improved quality of life. This article describes approaches taken in computing education to address the issue of sustainability. It presents results of a systematic review of the literature on sustainability in computing education. From a set of 572 publications extracted from six large digital libraries plus snowballing, we distilled and analyzed 89 relevant primary studies. Using an inductive and deductive thematic analysis, we study (i) conceptions of sustainability, computing, and education; (ii) implementations of sustainability in computing education; and (iii) research on sustainability in computing education. We present a framework capturing learning objectives and outcomes as well as pedagogical methods for sustainability in computing education. These results can be mapped to existing standards and curricula in future work. We find that only a few of the articles engage with the challenges as calling for drastic systemic change, along with radically new understandings of computing and education. We suggest that future work should connect to the substantial body of critical theory, such as feminist theories of science and technology. Existing research on sustainability in computing education may be considered rather immature, as the majority of articles are experience reports with limited empirical research.

Existing requirements engineering approaches manage broadly scoped requirements and constraints in a fashion that is largely two-dimensional, where functional requirements serve as the base decomposition with non-functional requirements cutting across them. Therefore, crosscutting functional requirements are not effectively handled. This in turn leads to architecture trade-offs being mainly guided by the non-functional requirements, so that the system quality attributes can be satisfied. In this paper, we propose a uniform treatment of concerns at the requirements engineering level, regardless of their functional, non-functional or crosscutting nature. Our approach is based on the observation that concerns in a system are, in fact, a subset, and concrete realisations, of abstract concerns in a meta concern space. One can delineate requirements according to these abstract concerns to derive more system-specific, concrete concerns. We introduce the notion of a compositional intersection, which allows us to choose appropriate sets of concerns in our multi-dimensional separation as a basis to observe trade-offs among other concerns. This provides a rigorous analysis of requirements-level trade-offs as well as important insights into various architectural choices available to satisfy a particular functional or non-functional concern.