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Is That a Gun? the Influence of Features of Bags and Threat Items on Detection Performance
Published in Philip D. Bust, Contemporary Ergonomics 2006, 2020
Xi Liu, Alastair Gale, Kevin Purdy, Tao Song
The eye movement data needed to be related to the threat items. The approach taken was to generate an area of interest (AOI) around each threat item and then to consider eye fixation data which fell within each AOI. Given the irregular form of threat items the dimensions of the area of interest (AOI) were determined by: the form of each threat item; the visual angle subtended by the fovea, and the accuracy of the eye-tracker (0.5∼0.7°). The foveola is the area of the retina that provides the best visual resolution and subtends a visual angle of about 1.2° (Schwartz, 1994). The AOI was estimated to be an area which had a similar form to the threat item profile, but was 1 cm wider than the edge of the item, which at a viewing distance of 70 cm subtended 1° visual angle.
Detection of macular diseases in optical coherence tomography image
Published in International Journal of Parallel, Emergent and Distributed Systems, 2020
Xiaoming Liu, Zhou Yang, Wei Hu, Jun Liu, Kai Zhang
According to the anatomical definition of retina around macular regions [25], an OCT image is divided into three zones: fovea (Fovea), parafovea (PA) and perifovea (PE). Pathological change occurs mostly in these three zones. Fovea is about 1.5 mm in diameter, and is located at the centre of macular region. Foveola is the centre of fovea and the diameter is about 0.35 mm. PA is an annular region with 0.5 mm in width around Fovea. PA can be further subdivided into left parafovea (PA_L) and right parafovea (PA_R). PA_L and PA_R are approximately symmetric about Fovea. PE is an annular region with 1.5 mm in width around PA. Similarly, PE can be divided into left perifovea (PE_L) and right perifovea (PE_R). Figure 5 shows the schematic diagram of macular region division. In this paper, all features are calculated in each sub-region, which takes the location of lesion into consideration.