itruction of each subway among other conditions. Also the influence of seasonal .3.2 Comparison of ... Comparison of the concentrations of indoor PM monitored in an underground and a ground level subway s ... 2.3 Data analysis 2. Materials and method Its principle is to utilize a light scattering technique
from single projections at multiple angles in what are known as slices. In CT the 3D body is reduced ... to 2D slices - a development made possible by a computer. Each ray represents an individual ... measurement of the linear attenuation coefficient. After preprocessing steps, which account for geometric