title: Performance of a building integrated photovoltaic/thermal (BIPVT) solar collector

authors: Anderson, Timothy Nicholas

subjects: photovoltaics

abstract: The idea of combining photovoltaic and solar thermal collectors (PVT collectors) to provide electrical and heat energy is an area that has, until recently, received only limited attention. Although PVTs are not as prevalent as solar thermal systems, the integration of photovoltaic and solar thermal collectors into the walls or roofing structure of a building could provide greater opportunity for the use of renewable solar energy technologies. In this study, the design of a novel building integrated photovoltaic/thermal (BIPVT) solar collector was theoretically analysed through the use of a modified Hottel–Whillier model and was validated with experimental data from testing on a prototype BIPVT collector.
The results showed that key design parameters such as the fin efficiency, the thermal conductivity between the PV cells and their supporting structure, and the lamination method had a significant influence on both the electrical and thermal efficiency of the BIPVT. Furthermore, it was shown that the BIPVT could be made of lower cost materials, such as pre-coated colour steel, without significant decreases in efficiency.
Finally, it was shown that by integrating the BIPVT into the building rather than onto the building could result in a lower cost system. This was illustrated by the finding that insulating the rear of the BIPVT may be unnecessary when it is integrated into a roof above an enclosed air filled attic, as this air space acts as a passive insulating barrier.

text: Performance of a building integrated photovoltaic/thermal (BIPVT) solar collector The idea of combining photovoltaic and solar thermal collectors (PVT collectors) to provide electrical and heat energy is an area that has, until recently, received only limited attention. Although PVTs are not as prevalent as solar thermal systems, the integration of photovoltaic and solar thermal collectors into the walls or roofing structure of a building could provide greater opportunity for the use of renewable solar energy technologies. In this study, the design of a novel building integrated photovoltaic/thermal (BIPVT) solar collector was theoretically analysed through the use of a modified Hottel–Whillier model and was validated with experimental data from testing on a prototype BIPVT collector.
The results showed that key design parameters such as the fin efficiency, the thermal conductivity between the PV cells and their supporting structure, and the lamination method had a significant influence on both the electrical and thermal efficiency of the BIPVT. Furthermore, it was shown that the BIPVT could be made of lower cost materials, such as pre-coated colour steel, without significant decreases in efficiency.
Finally, it was shown that by integrating the BIPVT into the building rather than onto the building could result in a lower cost system. This was illustrated by the finding that insulating the rear of the BIPVT may be unnecessary when it is integrated into a roof above an enclosed air filled attic, as this air space acts as a passive insulating barrier.

year: 2009

title: Positive effects of blue light on motor coordination in older adults: A pilot study

authors: Beaven, Christopher Martyn

abstract: Purpose: Falls are a risk factor for mortality in older adults. Lighting interventions can improve cognitive and motor task performance, but the effect on postural control with relevance to falling is unknown. Methods: Sixteen older adults participated in an intervention study with blue-enriched light delivered visually and/or transcranially for 12 min. Postural control in three conditions (60s eyes-open, dual-task, and eyes-closed), lower-limb motor coordination, and cognitive function were assessed. Results: Relative to placebo, visual blue-enriched light improved reaction time in the motor coordination task by 0.073 ± 0.035s (d = 0.77 ± 0.39; p = 0.003). Visual exposure decreased Area of Sway relative to the combined (d = 0.38 ± 0.26; p = 0.020) and placebo interventions (d = 0.47 ± 0.42; p = 0.067), with no significant effect on cognition. Conclusion: Blue-enriched lighting demonstrates a novel approach to positively impact postural control and motor coordination in older adults. By impacting metrics associated with fall risk, light interventions may provide a clinical countermeasure to decrease the human costs of falls.

text: Positive effects of blue light on motor coordination in older adults: A pilot study Purpose: Falls are a risk factor for mortality in older adults. Lighting interventions can improve cognitive and motor task performance, but the effect on postural control with relevance to falling is unknown. Methods: Sixteen older adults participated in an intervention study with blue-enriched light delivered visually and/or transcranially for 12 min. Postural control in three conditions (60s eyes-open, dual-task, and eyes-closed), lower-limb motor coordination, and cognitive function were assessed. Results: Relative to placebo, visual blue-enriched light improved reaction time in the motor coordination task by 0.073 ± 0.035s (d = 0.77 ± 0.39; p = 0.003). Visual exposure decreased Area of Sway relative to the combined (d = 0.38 ± 0.26; p = 0.020) and placebo interventions (d = 0.47 ± 0.42; p = 0.067), with no significant effect on cognition. Conclusion: Blue-enriched lighting demonstrates a novel approach to positively impact postural control and motor coordination in older adults. By impacting metrics associated with fall risk, light interventions may provide a clinical countermeasure to decrease the human costs of falls.

year: 2024-01-01

title: Māori Goddesses in Literature Part 1: pre 1880 - 1900

authors: Yates-Smith, Aroha

subjects: Atua wāhine

abstract: Many contemporary Māori are familiar with atua wāhine, Māori goddesses, through accounts that have been passed on to them by word of mouth. Few, however, have had an opportunity to consult accounts of atua wāhine that date from the early period of Māori-Pākehā contact. Those who wish to do so may have considerable difficulty in sifting through all of the written materials for the information they seek. For this reason, this paper provides a review of the literature pertaining to atua wāhine from pre-1880 to 1900, together with a commentary on the sources to which reference is made. A review of literature on atua wāhine which appeared after 1900 will appear in the second volume of this journal.

text: Māori Goddesses in Literature Part 1: pre 1880 - 1900 Many contemporary Māori are familiar with atua wāhine, Māori goddesses, through accounts that have been passed on to them by word of mouth. Few, however, have had an opportunity to consult accounts of atua wāhine that date from the early period of Māori-Pākehā contact. Those who wish to do so may have considerable difficulty in sifting through all of the written materials for the information they seek. For this reason, this paper provides a review of the literature pertaining to atua wāhine from pre-1880 to 1900, together with a commentary on the sources to which reference is made. A review of literature on atua wāhine which appeared after 1900 will appear in the second volume of this journal.

year: 2000-10