Motivated by opportunities in smart lighting, energy efficiency, and ubiquitous sensing, we present the design of polychromatic solid-state lighting controlled using a sensor network. We developed both a spectrally tunable light source and an interactive lighting testbed to study the effects of systems that adjust in response to changing environmental lighting conditions and users' requirements of color and intensity. Using both linear and nonlinear optimization, the setpoints of overdetermined systems (greater than three wavelengths) and the energy consumption of the network are adjusted according to the room's lighting conditions (e.g., lux and color temperature of multiple fixtures). Using these techniques, it is possible to maximize luminous efficacy or the color rendering index for a given intensity and color temperature. We detail the system modeling, design, optical calibration, and control theory required to modulate the luminous output and minimize wasted energy.

Despite international growth of, and policy interest in, divorce and separation since the 1970s, there is still surprisingly little known about non-residential fatherhood. This paper presents a ‘father-centric’ analysis and provides one of the first profiles of non-residential fatherhood in early millennium UK. Using data from Understanding Society Wave 1, a nationally representative survey of over 30,000 households in the UK, we found 1,070 men self-identifying as having a non-resident child under 16 years old (https://www.understandingsociety.ac.uk). We estimate a prevalence of 5 per cent of British men having a non-resident dependent child. Through latent class analysis, four distinct groups of non-resident fathers are identified: ‘Engaged’ fathers, ‘Less Engaged’ fathers, ‘Disengaged’ fathers and ‘Distance’ fathers. Our analysis finds that non-resident fathers form a heterogeneous group in terms of their socio-demographic profile and family behaviour. It is recommended that legislation and policy concerning fathers in post-separation families are sensitive to variation as well as commonality in socio-economic conditions and family lives and situations

This article examines the working lives of British couple families across the first decade of the millennium using EU Labour Force Survey data (2001-13) taking a multiple equilibria approach. Some growth in dual full-time earners, increased working hours of mothers in part-time employment and a growing proportion of households with 'non-standard' working patterns are all identified, suggesting both a convergence and greater diversity in economic provisioning within parent couple households. Household employment patterns remain strongly associated with maternal education and family size but are becoming less sensitive to the age of the youngest child. The dual full-time earner model is growing in significance for British parents of young children but a new gender egalitarian equilibrium has not yet been reached.

A conditional right to request flexible working arrangements (FWAs) has existed for most UK employee parents since 2003. However, there are growing concerns about access, particularly among fathers. Using nationally representative data from the 2015 UK Household Longitudinal Survey, this article examines fathers’ perceptions of the availability of hours reduction, schedule flexibility and working from home. Results show that almost one-third of fathers believe that FWAs that reduce working hours are unavailable to them, compared with one-tenth of mothers. There are no gender differences in perceptions of availability of schedule and location flexibility. Among fathers, those with lower education levels, in lower status occupations, working in the private sector and in workplaces that do not have trade union presence are more likely to believe that FWAs are unavailable. Therefore, even though most employees now have the right to request FWAs, a significant minority of fathers do not perceive FWAs to be available to them.

An increasing number of internet-connected LED lighting fixtures and bulbs have recently become available. This development, in combination with emerging hardware and software solutions for activity recognition, establish an infrastructure for context-aware lighting. Automated lighting control could potentially provide a better user experience, increased comfort, higher productivity, and energy savings compared to static uniform illumination. The first question that comes to mind when thinking about context-aware lighting is how to determine the relevant activities and contexts. Do we need different lighting for reading a magazine and reading a book, or maybe just different lighting for reading versus talking on the phone? How do we identify the relevant situations, and what are the preferred lighting settings? In this paper we present three steps we took to answer these questions and demonstrate them via an adaptive fivechannel solid-state lighting system with continuous contextual control. We implemented a multidimensional user interface for manual control as well as an autonomous solution using wearable sensors. We enable a simple set of sensors to manipulate complicated lighting scenarios by indirectly simplifying and reducing the complexity of the sensor-lighting control space using human-derived criteria. In a preliminary user study, we estimated significant energy savings of up to 52% and showed multiple future research directions, including behavioral feedback.

Abstract-We pose the problem of turning off a single luminaire (or group) as an optimal stopping problem. We present the stationary and first-passage analysis of motion data obtained using custom wireless nodes in an open office floor plan. These calculations allow us to estimate the state of the network and calculate the probability and expected number of steps to visit a state from any arbitrary state. We also investigate if there is any evidence of clustering amongst the nodes by studying the covariance of the dataset. The data indicate the existence of clustering within the lattice. In other words, the analysis of random walk prevents luminaires from accidentally shutting off and dimensionality reduction determines the correct zoning of lighting via the occupants' movements.

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