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M. Gladt, T. Bednar:
"A New Method For The Calculation Of The Sky View Factor For Non-Rectangular Surroundings";
Talk: 13th International Conference of the International Building Performance Simulation Association, Chambéry, France; 2013-08-25 - 2013-08-28; in: "Building Simulation Conference", (2013), Paper ID 995, 6 pages.

The sky view factor (SVF) represents the relationship between the visible portion of the sky and the portion covered by the surrounding objects. It is significant e.g. in urban zones where the nightly cooling of a building has an intense correlation with the long-wave radiation emitted by the surrounding objects. The methods of calculating the SVF comprise fisheye-lens photographs analysis as well as mathematical models or image processing. A well-known method for the calculation is based on a vector-based presentation of the model. The projection of the model onto the hemisphere is divided into slices to approximate the calculation of the resulting polygon with the calculation of the SVF for the rectangles resulting from the slices of the previous step.
The approach has two major drawbacks: The process of discretization slows the calculation down and the accuracy of the result depends on the particularity of discretization. This paper presents a method where no more discretization is needed which results in lower calculation times and more accurate results