Asymmetrical awnings : a way to increase daylight in buildings without increasing the overheating

Different shapes of asymmetric awnings for east and west windows are investigated mathematically as well as by measurement in a model. A box with 90 cm side and a 30x30 cm window was placed outdoor in overcast weather and the daylight factor was measured at the bottom of the box when the window was unshaded or equipped with different awnings. The average daylight factor in the box decreased from 4.6% for the unshaded window to 1.0% when a full awning was used. With “the best” asymmetrical awning, the average daylight factor was 80% larger than with the full awing. Using Dutch climate, calculation of the energy from direct radiation transmitted through the window during the cooling season showed that this was decreased from 100% as an annual mean for the unshaded window down 22% with a full awing. With “the best” asymmetrical awning, 26% of the energy was transmitted. Calculation of the indoor temperature in a hypothetical row house in Netherlands show that the use of either normal or asymmetrical awnings considerable decrease the indoor temperature during the hot season. Therefore the use of asymmetrical awnings for east or west faced windows considerable can increase the daylight in buildings, with almost no change in overheating, compared to if traditional awnings are used.

Ellipsis as a marker of interaction in spoken discourse

In this article, we discuss strategies for interaction in spoken discourse, focusing on ellipsis phenomena in English. The data comes from the VOICE corpus of English as a Lingua Franca, and we analyse education data in the form of seminar and workshop discussions, working group meetings, interviews and conversations. The functions ellipsis carries in the data are Intersubjectivity, where participants develop and maintain an understanding in discourse; Continuers, which are examples of back channel support; Correction, both self- and other-initiated; Repetition; and Comments, which are similar to Continuers but do not have a back channel support function. We see that the first of these, Intersubjectivity, is by far the most popular, followed by Repetitions and Comments. These results are explained as consequences of the nature of the texts themselves, as some are discussions of presentations and so can be expected to contain many Repetitions, for example. The speech event is also an important factor, as events with asymmetrical power relations like interviews do not contain so many Continuers. Our clear conclusion is that the use of ellipsis is a strong marker of interaction in spoken discourse.