To avoid this result may be influenced by the presence of spatial smoothing we repeated the analysis without using any spatial smoothing.
To explore the spatial and temporal diffusion trend of pandemic influenza in mainland China, a map of pandemic influenza spread was developed using trend surface analysis, which is a spatial smoothing method that uses polynomials with geographic coordinates, as defined by the central point of each county (12– 12).
These motion vectors are then refined using a new matching criterion and a spatial smoothing filter.
The following procedures were applied: motion correction using MCFLIRT, spatial smoothing using a Gaussian kernel of FWHM 5 mm, mean-based intensity normalization of all volumes by the global factor and high-pass temporal filtering.
Voxel-based analyses were conducted on baseline perfusion images using the spatial smoothing with a three-dimensional isotropic Gaussian kernel size (FWHM; 8 mm).
After obtaining the virtual array signal model in (12), all the impinging DOAs can be estimated by using the spatial smoothing MUSIC algorithm or the compressive sensing (CS) algorithm, which have been discussed in [10 14].
This study analyzed the spatial distribution of HFRS in Liaoning Province, China, during 2000 to 2005 using the spatial smoothing and spatial scan statistic method.
The following preprocessing steps were performed: Talairach transformation, temporal slice scan time correction using sinc interpolation, 3D motion correction using trilinear interpolation, spatial smoothing (8 mm Gaussian kernel), and a temporal high-pass filter (3 cycles per time course).
We applied slice scan time correction using sinc interpolation, 3D motion correction using trilinear interpolation, spatial smoothing (8 mm Gaussian kernel), and a temporal high-pass filter (low frequency cut-off: 3 cycles per run).
