China
Africa
Explore chapters and articles related to this topic
Vision System
Published in Joseph D. Bronzino, Donald R. Peterson, Biomedical Engineering Fundamentals, 2019
Aaron P. Batista and George D. Stetten
Other cells, more common than simple cells, are termed complex cells. Complex cells also respond to bars within their receptive eld, but unlike simple cells, they are invariant to the position of the bar within the receptive eld. is may contribute in part to the translation invariance of our visual experience. Complex cells will respond to movement perpendicular to the orientation of the edge. Some prefer one direction of movement to its opposite. Some complex and simple cells are end-stopped, meaning they re only if the illuminated bar or edge terminates within the cell’s receptive eld. Presumably, these cells detect corners, curves, or discontinuities in borders and lines. End-stopping takes place in layers 2 and 3 of the primary visual cortex. From the LGN through the simple cells and complex cells, there appears to be a sequential processing of the image. A remarkable feature in the organization of V1 is binocular convergence, in which a single neuron responds to identical receptive elds in both eyes, including location, orientation, and directional sensitivity to motion. is does not occur in the LGN, where axons from the le and right eyes are still segregated into dierent layers. Some binocular neurons are equally weighted in terms of responsiveness to both eyes, while others are more sensitive to one eye than to the other. V1 is also organized into columns containing cells in which one eye dominates, called ocular dominance columns. Ocular dominance columns occur in adjacent pairs, one for each eye, and are prominent in predatory animals with forward-facing eyes, such as cats, chimpanzees, and humans. ey are nearly absent in rodents and other prey animals whose eyes face outward.
Novel hybrid DCNN–SVM model for classifying RNA-sequencing gene expression data*
Published in Journal of Information and Telecommunication, 2019
Phuoc-Hai Huynh, Van-Hoa Nguyen, Thanh-Nghi Do
DCNN is designed to process multiple data types, especially two-dimensional images that are directly inspired by the visual cortex of the human brain. In the human brain, there is a hierarchy of two basic cell types: simple cells and complex cells (Hubel & Wiesel, 1963). On the one hand, simple cells react to primitive patterns in sub-regions of visual stimulator. One the other hand, complex cells synthesize the information from simple cells to identify more intricate forms. Therefore, the visual cortex is a powerful and natural visual processing system. DCNN is applied to imitate three key ideas including local connectivity, invariance to location, and invariance to local transition (LeCun, Bengio, & Hinton, 2015).