New lighting technologies create new opportunities that may contribute to people's experience of light. These opportunities are a result of the increased variety and freedom in terms of colour, form factor and connectivity of the lights. To allow people to fully benefit from the potential of such novel lighting systems, there is a need for a new user interaction paradigm. To develop this paradigm, we have to better understand the aspects that play a part in the interaction with lighting, paying special attention to people's motivation for interaction. This paper reports on a context-mapping study that was performed to gain insight in these aspects. As result, we present a set of seven themes that regard the interaction with lighting in the current situation and in the future. These themes provide an overview of the relevant aspects in this domain and contain considerations and opportunities for the design of new interfaces for novel lighting systems. We conclude that people have different levels of lighting needs that are highly dependent on context and that also require control at different levels. The context and lighting needs have a large influence on the extent to which people are motivated to adjust their lighting. Moreover, the lighting interface itself has a large effect on this motivation, mainly influenced by the degrees of freedom, the control location and availability, the degree of automation and general interaction qualities.

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The feasibility of Model Predictive Control (MPC) applied to a laboratory gas turbine installation is investigated. MPC explicitly incorporates (input-and output-) constraints in its optimizations, which explains the choice for this computationally demanding control strategy. Strong nonlinearities, displayed by the gas turbine installation, cannot always be handled adequately by standard linear MPC. Therefore, we resort to nonlinear methods, based on successive linearization and nonlinear prediction as well as the combination of these. We implement these methods, using a nonlinear model of the installation, and compare them to linear MPC. It is shown that controller performance can be improved, without increasing controller execution-time excessively.

Instant Messaging (IM) is a popular chatting platform on the internet and increasingly permeates teenage life. Even intimate and emotional content is discussed. As touch is a powerful signal for emotional content, haptic signals, and especially hapticons can contribute to overcome the inevitable loss of subtle non-verbal communication cues. Audiovisual extensions of IM to share emotions, in particular emoticons, have been received enthusiastically by IM users. This indicates a realistic user-need for hapticons in IM.The Haptic Instant Messaging (HIM) framework introduced in this paper combines communication of textual messages with haptic effects and hapticons. The application is build as an open framework and supports small chatting communities to explore the design and use of hapticons and haptic IO devices. Researchers can use the HIM framework to monitor the use of haptics in communication and how haptics contribute to the fun and meaning of instant messaging.