Few-shot remote sensing image scene classification based on multiscale covariance metric network (MCMNet).

Few-shot learning (FSL) is a paradigm that simulates the fast learning ability of human beings, which can learn the feature differences between two groups of small-scale samples with common label space, and the label space of the training set and the test set is not repeated. By this way, it can quickly identify the categories of the unseen image in the test set. This method is widely used in image scene recognition, and it is expected to overcome difficulties of scarce annotated samples in remote sensing (RS). However, among most existing FSL methods, images were embed into Euclidean space, and the similarity between features at the last layer of deep network were measured by Euclidean distance. It is difficult to measure the inter-class similarity and intra-class difference of RS images. In this paper, we propose a multi-scale covariance network (MCMNet) for the application of remote sensing scene classification (RSSC). Taking Conv64F as the backbone, we mapped the features of the 1, 2, and 4 layers of the network to the manifold space by constructing a regional covariance matrix to form a covariance network with different scales. For each layer of features, we introduce the center in manifold space as a prototype for different categories of features. We simultaneously measure the similarity of three prototypes on the manifold space with different scales to form three loss functions and optimize the whole network by episodic training strategy. We conducted comparative experiments on three public datasets. The results show that the classification accuracy (CA) of our proposed method is from 1.35 % to 2.36% higher than that of the most excellent method, which demonstrates that the performance of MCMNet outperforms other methods.

A community detection algorithm based on topology potential and spectral clustering.

Community detection is of great value for complex networks in understanding their inherent law and predicting their behavior. Spectral clustering algorithms have been successfully applied in community detection. This kind of methods has two inadequacies: one is that the input matrixes they used cannot provide sufficient structural information for community detection and the other is that they cannot necessarily derive the proper community number from the ladder distribution of eigenvector elements. In order to solve these problems, this paper puts forward a novel community detection algorithm based on topology potential and spectral clustering. The new algorithm constructs the normalized Laplacian matrix with nodes' topology potential, which contains rich structural information of the network. In addition, the new algorithm can automatically get the optimal community number from the local maximum potential nodes. Experiments results showed that the new algorithm gave excellent performance on artificial networks and real world networks and outperforms other community detection methods.

An improved topology-potential-based community detection algorithm for complex network.

Topology potential theory is a new community detection theory on complex network, which divides a network into communities by spreading outward from each local maximum potential node. At present, almost all topology-potential-based community detection methods ignore node difference and assume that all nodes have the same mass. This hypothesis leads to inaccuracy of topology potential calculation and then decreases the precision of community detection. Inspired by the idea of PageRank algorithm, this paper puts forward a novel mass calculation method for complex network nodes. A node's mass obtained by our method can effectively reflect its importance and influence in complex network. The more important the node is, the bigger its mass is. Simulation experiment results showed that, after taking node mass into consideration, the topology potential of node is more accurate, the distribution of topology potential is more reasonable, and the results of community detection are more precise.