Context petri nets : enabling consistent composition of context-dependent behavior

Ensuring the consistent composition of context-dependent behavior is a major challenge in context-aware systems. Developers have to manually identify and validate existing interactions between behavioral adaptations, which is far from trivial. This paper presents a run-time model for the consistency management of context-dependent behavior, called context Petri nets. Context Petri nets provide a concrete representation of the execution context of a system, in which it is possible to represent the interactions due to dynamic and concurrent context changes. In addition, our model allows the definition of dependency relations between contexts, which are internally managed to avoid inconsistencies. We have successfully integrated context Petri nets with Subjective-C, a context-oriented programming language. We show how our model can be cleanly combined with the abstractions of the language to define and manage context-dependent behavior

Actions to reduce the impact of construction products on indoor air: outcomes of the European project Healthy Air

The European project - HealthyAir is a network project involving six institutions in Europe on actions and activities that address the effects of construction products on indoor air. Different ways to improve indoor air quality were reviewed, ranging from source control to education of occupants on how to manage the built environment to achieve healthy and acceptable indoor air. Through literature study, organised workshops with scientific experts and building professionals as well as via interviews with three stakeholder groups: producers of construction products, architects and housing corporations; requirements for information, guidance and actions to improve indoor air quality were identified. These requirements formed the basis of a possible approach to improve indoor air quality: education and awareness, regulations and policies and further research and development