Measurement day and the outdoor diffuse and global horizontal illuminances
and irradiances at each time step (five minutes).
metric is a climate-based, whole-year metric calculated for each time period as a weighted average of illuminances
from each sky type.
While not designed to compete with a professional meter, the new app will provide average illuminances
in lux and footcandles, keep a running total of readings and average illuminance
for a given space, and record a log of past readings.
In the first decades of the 20th century, the IES promulgated so-called "lighting codes" that described illuminances
appropriate for various applications, including industry, offices, and schools [IES 1912; 1916; 1925; 1928].
The deviation in the user set levels was large with both of the tested lightings and there were indications that adjustment range affected to user set illuminances
5, it will be allowable for designers to design to reduced illuminances
, to maintain the same visual acuity as presumed in the IES Illuminance
It would be beneficial to have a time- and cost-effective method to predict illuminances
in the surgical site and to test if a virtual prototype of a surgical luminaire complies to [IEC 2009], before building the device.
Later, two advanced daylight metrics were brought into use: daylight autonomy (Reinhart, 2002; Tzempelikos and Athienitis, 2005, 2007) and useful daylight illuminances
(Nabil and Mardaljevic, 2005, 2006; Shen and Tzempelikos, 2010).
Statistical analysis of the results did not indicate differences between illuminances
ratios found using the six visual equality objectives to be significant.
The box plot in Figure 1 shows the range of desktop illuminances
, with the workstations grouped by their distance from the window and window orientation.
Other sophisticated methods exist for control of venetian blinds and prediction of indoor illuminances
based on correlations between calibrated interior sensors (Park and Athienitis 2003).
Luminances were extracted from these HDR pictures and those measured with the luminance meter were then weighted according to the horizontal illuminances
recorded in the minor box.