Attention-Based Spatial and Spectral Network with PCA-Guided Self-Supervised Feature Extraction for Change Detection in Hyperspectral Images

Joint analysis of spatial and spectral features has always been an important method for change detection in hyperspectral images. However, many existing methods cannot extract effective spatial features from the data itself. Moreover, when combining spatial and spectral features, a rough uniform global combination ratio is usually required. To address these problems, in this paper, we propose a novel attention-based spatial and spectral network with PCA-guided self-supervised feature extraction mechanism to detect changes in hyperspectral images. The whole framework is divided into two steps. First, a self-supervised mapping from each patch of the difference map to the principal components of the central pixel of each patch is established. By using the multi-layer convolutional neural network, the main spatial features of differences can be extracted. In the second step, the attention mechanism is introduced. Specifically, the weighting factor between the spatial and spectral features of each pixel is adaptively calculated from the concatenated spatial and spectral features. Then, the calculated factor is applied proportionally to the corresponding features. Finally, by the joint analysis of the weighted spatial and spectral features, the change status of pixels in different positions can be obtained. Experimental results on several real hyperspectral change detection data sets show the effectiveness and advancement of the proposed method.

‘Every love story is a ghost story’ : The Spectral Network of Laurie Anderson’s Heart of a Dog (2015)

While it has been described as ‘a paean to a canine friend’ and ‘a meditation on love and loss’, Laurie Anderson’s Heart of a Dog (2016) can also be understood as a network of ghost stories. Drawing on Anderson’s idiosyncratic multimedia technique (foregrounding technology) and conceptualizing of the future, this chapter explores the ways in which the figures of 9/11, Lou Reed, David Foster Wallace, Gordon Matta-Clark, and the Bardo course through Heart of a Dog. Exploring the implications of the juxtaposition of these themes and Anderson’s oeuvre, Williams positions the film in relation to a confluence of network theory and hauntology as a particular rendering of 21st-century subjectivity.