Big data analytics (BDA) is a systematic approach for analyzing and identifying different patterns, relations, and trends within a large volume of data. In this paper, we apply BDA to criminal data where exploratory data analysis is conducted for visualization and trends prediction. Several the state-of-the-art data mining and deep learning techniques are used. Following statistical analysis and visualization, some interesting facts and patterns are discovered from criminal data in San Francisco, Chicago, and Philadelphia. The predictive results show that the Prophet model and Keras stateful LSTM perform better than neural network models, where the optimal size of the training data is found to be three years. These promising outcomes will benefit for police departments and law enforcement organizations to better understand crime issues and provide insights that will enable them to track activities, predict the likelihood of incidents, effectively deploy resources and optimize the decision making process.
Heterogeneous change detection (HCD) is a process to determine the change information by analyzing heterogeneous images of the same geographic location taken at different times, which plays an important role in remote sensing applications such as disaster response and environmental monitoring. However, the different imaging mechanisms result in different visual appearances in heterogeneous images, making it difficult to accurately detect changes through direct comparison. To address this problem, we propose a novel self-supervised dual-branch framework (ICSF) for HCD that incorporates inter-modal and cross-modal learning. First, in the inter-modal branch, we perform the contrastive learning on heterogeneous images within their respective modalities to learn the robust and discriminative features, rather than relying on the raw spectral or spatial information from these images. Second, in the cross-modal branch, we perform cross-modal reconstruction to ensure the obtained features exhibit consistent comparability, thereby facilitating the extraction of rich information of the real changes within the images. Next, the difference images (DIs) computed from both branches are further refined using a superpixel segmentation strategy to preserve the consistency of differences within the same ground object. Experimental results on five public datasets with different modality combinations and change events demonstrate the effectiveness of the proposed approach in comparison to ten state-of-the-art methods, achieving the best performance with an average overall accuracy of 95.88% and an average Kappa coefficient of 74.20%.
Hyperspectral imaging (HSI) is widely used in various fields owing to its rich spectral information. Nonetheless, the high dimensionality of HSI and the limited number of labeled data remain significant obstacles to HSI classification technology. To alleviate the above problems, we propose an attention-embedded triple-branch fusion convolutional neural network (AETF-Net) for an HSI classification. The network consists of a spectral attention branch, a spatial attention branch, and a multi-attention fusion branch (MAFB). The spectral branch introduces the cross-channel attention to alleviate the band redundancy problem in high dimensions, while the spatial branch preserves the location information of features and eliminates interfering image elements by a bi-directional spatial attention module. These pre-extracted spectral and spatial attention features are then embedded into a novel MAFB with large kernel decomposition technique. The proposed AETF-Net achieves multi-attention features reuse and extracts more representative and discriminative features. Experimental results on three well-known datasets demonstrate the superiority of the method AETF-Net.