Spatial activity recognition in a smart home environment using a chemotactic model

Spatial activity recognition is challenging due to the amount of noise incorporated during video tracking in everyday environments. We address the spatial recognition problem with a biologically-inspired chemotactic model that is capable of handling noisy data. The model is based on bacterial chemotaxis, a process that allows bacteria to change motile behaviour in relation to environmental gradients. Through adoption of chemotactic principles, we propose the chemotactic model and evaluate its performance in a smart house environment. The model exhibits greater than 99% recognition performance with a diverse six class dataset and outperforms the Hidden Markov Model (HMM). The approach also maintains high accuracy (90-99%) with small training sets of one to five sequences. Importantly, unlike other low-level spatial activity recognition models, we show that the chemotactic model is capable of recognising simple interwoven activities.

Dynamic privacy assessment in a smart house environment using multimodal sensing

Surveillance applications in private environments such as smart houses require a privacy management policy if such systems are to be accepted by the occupants of the environment. This is due to the invasive nature of surveillance, and the private nature of the home. In this article, we propose a framework for dynamically altering the privacy policy applied to the monitoring of a smart house based on the situation within the environment. Initially the situation, or context, within the environment is determined; we identify several factors for determining environmental context, and propose methods to quantify the context using audio and binary sensor data. The context is then mapped to an appropriate privacy policy, which is implemented by applying data hiding techniques to control access to data gathered from various information sources. The significance of this work lies in the examination of privacy issues related to assisted-living smart house environments. A single privacy policy in such applications would be either too restrictive for an observer, for example, a carer, or too invasive for the occupants. We address this by proposing a dynamic method, with the aim of decreasing the invasiveness of the technology, while retaining the purpose of the system.

Privacy and the access of information in a smart house environment

In this paper we present a framework for addressing privacy issues raised by the monitoring of assisted living smart house environments. In home environments, the conflict between the goals of the surveillance, and the private nature of the home, raises the issue of occupant privacy. This issue needs to be addressed if applications are to be accepted by the occupant. We identify four key properties required for the design of privacy sensitive ubiquitous computing applications. Subsequently, we develop a dynamic and flexible method for implementing privacy measures through controlling access to data, and an interface to provide feedback to the occupant, enabling them to control the implemented privacy measures. We form a generic framework for implementing privacy sensitive ubiquitous computing applications based on previous applications within the field. This framework was then extended and used to develop a specific framework for a privacy sensitive smart house. The approach proposed in the framework dynamically applies privacy measures to multi-modal data according to the situation, or context, of the environment. We further test an implementation of the privacy measures, and detail methods to implement feedback and control. The approach aims to decrease the invasiveness of the surveillance, while retaining the purpose of the assisted living environment.

Individual, social and home environment determinants of change in children's television viewing: the Switch-Play intervention

Understanding potential determinants of change in television (TV) viewing among children may enhance the effectiveness of programs targeting this behaviour. This study aimed to investigate the contribution of individual, social and home environment factors among 10-year-old Australian children to change in TV viewing over a 21-month period. A total of 164 children (49% boys) completed a 19-lesson (9-month) intervention program to reduce TV viewing time. Children completed self-administered surveys four times over 21 months (pre- and post-intervention, 6- and 12-month follow-up). Baseline factors associated with change in TV viewing during the intervention and follow-up periods were: ‘asking parents ≥once/week to switch off the TV and play with them’ (21.6 min/day more than those reporting <once/week, p = 0.007); being able to ‘watch just 1 h of TV per day’ (26.1 min/day less than those who could not, p = 0.010); ‘watching TV no matter what was on’ (36.6 min/day more than those who did not, p < 0.001); and ‘continuing to watch TV after their program was over’ (33.0 min/day more than those who did not, p = 0.006). With every unit increase in baseline frequency of TV viewing with family and friends, children spent on average 4.0 min/day more watching TV over the 21-month period (p = 0.047). Baseline number and placement of TVs at home did not predict change in children's TV viewing over the 21 months. Greater understanding of the family dynamics and circumstances, as well as the individual and social determinants of TV viewing, will be required if we are to develop effective strategies for reducing TV viewing in children.

Are parental concerns about children's inactivity warranted, and are they associated with a supportive home environment?

This paper explores parental concern about children's activity levels and whether parents who are concerned about their child's activity provide a supportive environment, a sample of 615 parents of 5-6-year-old children and 947 parents of 10-12-year-old children completed a questionnaire. Just over 50% of parents reported they were concerned their child was not getting enough activity. Children of concerned parents were less active than those whose parents were not concerned. These findings suggest that parents who are concerned about their child's physical activity levels provided a less supportive environment for physical activity than parents who are not concerned. The challenge for public health will be to harness parental concerns and translate them into action.

Understanding children's sedentary behaviour : a qualitative study of the family home environment

Electronic media (EM) (television, electronic games and computer) use has been associated with overweight and obesity among children. Little is known about the time spent in sedentary behaviour (SB) among children within the family context. The aim of this study was to explore how the family home environment may influence children's electronic-based SB. Focus groups and family interviews were conducted with 11- to 12-year old children (n = 54) and their parents (n = 38) using a semi-structured discussion guide. Transcripts were analysed using a thematic content approach. A brief self-completed questionnaire was also used to measure leisure behaviour and electronic devices at home. Children incorporated both sedentary and physical activities into their weekly routine. Factors influencing children's EM use included parent and sibling modelling and reinforcement, personal cognitions, the physical home environment and household EM use rules and restrictions. Participants were not concerned about the excessive time children spent with EM. This under-recognition emerged as a personal influencing factor and was viewed as a major barrier to modifying children's electronic-based SB. Efforts to reduce SB in children should focus on the influencing factors that reciprocally interact within the family home. An emphasis on increasing awareness about the risks associated with spending excessive time in screen-based activities should be a priority when developing intervention strategies aimed at modifying the time children spend in SB.

Dynamic privacy in a smart house environment

A smart house can be regarded as a surveillance environment in which the person being observed carries out activities that range from intimate to more public. What can be observed depends on the activity, the person observing (e.g. a carer) and policy. In assisted living smart house environments, a single privacy policy, applied throughout, would be either too invasive for an occupant, or too restrictive for an observer, due to the conflicting goals of surveillance and private environments. Hence, we propose a dynamic method for altering the level of privacy in the environment based on the context, the situation within the environment, encompassing factors relevant to ensuring the occupant's safety and privacy. The context is mapped to an appropriate level of privacy, which is implemented by controlling access to data sources (e.g. video) using data hiding techniques. The aim of this work is to decrease the invasiveness of the technology, while retaining the purpose of the system.

Are parental concerns for child TV viewing associated with child TV viewing and the home sedentary environment?

Background
Time spent watching television affects multiple aspects of child and adolescent health. Although a diverse range of factors have been found to be associated with young people's television viewing, parents and the home environment are particularly influential. However, little is known about whether parents, particularly those who are concerned about their child's television viewing habits, translate their concern into action by providing supportive home environments (e.g. rules restricting screen-time behaviours, limited access to screen-based media). The aim of this study was to examine associations between parental concerns for child television viewing and child television viewing and the home sedentary environment.
Methods
Parents of children aged 5-6 years ('younger' children, n = 430) and 10-12 years ('older children', n = 640) reported usual duration of their child's television (TV) viewing, their concerns regarding the amount of time their child spends watching TV, and on aspects of the home environment. Regression analyses examined associations between parental concern and child TV viewing, and between parental concern and aspects of the home environment. Analyses were stratified by age group.
Results
Children of concerned parents watched more TV than those whose parents were not concerned (B = 9.63, 95% CI = 1.58-17.68, p = 0.02 and B = 15.82, 95% CI = 8.85-22.80, p < 0.01, for younger and older children respectively). Parental concern was positively associated with younger children eating dinner in front of the television, and with parental restriction of sedentary behaviours and offering sedentary activities (i.e. TV viewing or computer use) as a reward for good behaviour among older and young children. Furthermore, parents of older children who were concerned had fewer televisions in the home and a lower count of sedentary equipment in the home.
Conclusions
Children of concerned parents watched more TV than those whose parents who were not concerned. Parents appear to recognise excessive television viewing in their children and these parents appear to engage in conflicting parental approaches despite these concerns. Interventions targeting concerned parents may be an innovative way of reaching children most in need of strategies to reduce their television viewing and harnessing this parental concern may offer considerable opportunity to change the family and home environment.

Efficient Coxian duration modelling for activity recognition in smart environment with the hidden semi-Markov model

In this paper, we exploit the discrete Coxian distribution and propose a novel form of stochastic model, termed as the Coxian hidden semi-Makov model (Cox-HSMM), and apply it to the task of recognising activities of daily living (ADLs) in a smart house environment. The use of the Coxian has several advantages over traditional parameterization (e.g. multinomial or continuous distributions) including the low number of free parameters needed, its computational efficiency, and the existing of closed-form solution. To further enrich the model in real-world applications, we also address the problem of handling missing observation for the proposed Cox-HSMM. In the domain of ADLs, we emphasize the importance of the duration information and model it via the Cox-HSMM. Our experimental results have shown the superiority of the Cox-HSMM in all cases when compared with the standard HMM. Our results have further shown that outstanding recognition accuracy can be achieved with relatively low number of phases required in the Coxian, thus making the Cox-HSMM particularly suitable in recognizing ADLs whose movement trajectories are typically very long in nature.

The Digital Divide: Differences in Computer Use between Home and School in Low Socio-economic Households

This article examines information and communication technologies(ICTs) practices in the home and school settings of four disadvantaged families. It reports the findings of a year-long study that investigated the nexus between computer-mediated literacy practices at home and at school and whether this inter-connectivity could make a difference in school success. The findings indicate that there was disjunction between home and school use. The ``digital divide'' exists for the families of this study, not in terms of access but in the gap between ICT practices at home and school. Schools in this study did not integrate ICT skills learned and demonstratedin the home environment into ICT practices at school. The study concludes that constructing pedagogical connections between home and school ICT practices may begin to bridge the ``digital divide''.

Family and home correlates of television viewing in 12-13 year old adolescents: the Nepean study

Background
Few young people meet television viewing guidelines.
Purpose
To determine the association between factors in the family and home environment and watching television, including videos and DVDs, in early adolescence.
Methods
Cross-sectional, self-report survey of 343 adolescents aged 12–13 years (173 girls), and their parents (338 mothers, 293 fathers). Main measures were factors in the family and home environment potentially associated with adolescents spending ≥ 2 hours per day in front of the television. Factors examined included family structure, opportunities to watch television/video/DVDs, perceptions of rules and regulations on television viewing, and television viewing practices.
Results
Two-thirds of adolescents watched ≥ 2 hours television per day. Factors in the family and home environment associated with adolescents watching television ≥ 2 hours per day include adolescents who have siblings (Adjusted Odds Ratio [95%CI] AOR = 3.0 [1.2, 7.8]); access to pay television (AOR = 2.0 [1.1, 3.7]); ate snacks while watching television (AOR = 3.1 [1.8, 5.4]); co-viewed television with parents (AOR = 2.3 [1.3, 4.2]); and had mothers who watched ≥ 2 hours television per day (AOR = 2.4 [1.3, 4.6]).
Conclusion
There are factors in the family and home environment that influence the volume of television viewed by 12–13 year olds. Television plays a central role in the family environment, potentially providing a means of recreation among families of young adolescents for little cost. Interventions which target family television viewing practices and those of parents, in particular, are more likely to be effective than interventions which directly target adolescent viewing times.