We introduce TopoHunter, an efficient IPv6 Internet topology discovery system. The central concept of TopoHunter is to allocate more probing resources to target prefix spaces that yield greater topological benefits, as well as to their surrounding areas. To achieve this, we design a feedback-based target generation module comprised of a Target Prefix Probing Value Forest that maintains the estimated probing values of hierarchical target prefix spaces. Our system has successfully discovered the most extensive and complete IPv6 topology map to date, comprising over 144 million router interfaces and 251 million edges, covering 72.83% of autonomous systems and 43.36% of routing prefixes announced by the BGP system.

IP geolocation is essential for various location-aware Internet applications. With the rapid development of the IPv6 protocol, IPv6 geolocation is becoming increasingly important. High-accuracy IPv6 geolocation relies heavily on high-quality landmarks. However, existing landmark mining methods mainly focus on IPv4 landmarks, and cannot mine IPv6 landmarks or are extremely inefficient, making IPv6 geolocation accuracy hard to improve. In this paper, we present a novel IPv6 geolocation framework, LMGeo6, proposing a comprehensive IPv6 landmark mining methodology for high-accuracy IPv6 geolocation. LMGeo6 migrates IPv4 landmark mining methods and designs specific IPv6 landmark mining methods, improving the number and coverage of IPv6 landmarks significantly. Based on these designs, we implement the LMGeo6 system and conduct real-world experiments to validate its efficacy. The experiment results show that LMGeo6 can mine 62,697 IPv6 landmarks, improving 15× over the total of other methods. LMGeo6 landmarks cover 165 countries, 5,805 cities, and 4,030 ASes, improving over 300% and reaching the same scale as IPv4 landmarks.

Pedestrian trajectory prediction is an important technique of autonomous driving. In order to accurately predict the reasonable future trajectory of pedestrians, it is inevitable to consider social interactions among pedestrians and the influence of surrounding scene simultaneously, which can fully represent the complex behavior information and ensure the rationality of predicted trajectories obeyed realistic rules. In this article, we propose one new prediction model named social soft attention graph convolution network (SSAGCN), which aims to simultaneously handle social interactions among pedestrians and scene interactions between pedestrians and environments. In detail, when modeling social interaction, we propose a new social soft attention function, which fully considers various interaction factors among pedestrians. Also, it can distinguish the influence of pedestrians around the agent based on different factors under various situations. For the scene interaction, we propose one new sequential scene sharing mechanism. The influence of the scene on one agent at each moment can be shared with other neighbors through social soft attention; therefore, the influence of the scene is expanded both in spatial and temporal dimensions. With the help of these improvements, we successfully obtain socially and physically acceptable predicted trajectories. The experiments on public available datasets prove the effectiveness of SSAGCN and have achieved state-of-the-art results. The project code is available at https://github.com/WW-Tong/ssagcn_for_path_prediction.

In the field of human–computer interaction, there is a trend toward using emotional interaction and putting emotions at the center. However, traditional facial expression recognition is greatly affected by lighting, skin color and make-up, and is not well recognized. This paper addresses these shortcomings in the following areas: (1) The algorithm of infrared face feature localization is studied, using a combination of region growing algorithm to highlight the organ features of infrared faces, and the Harris corner point detection algorithm to detect the organ features of human beings and locate the location of the large organs related to expressions, such as eyes, nose and mouth. (2) The algorithm for feature extraction is investigated, and the local binarization LBP algorithm is proposed to extract the texture features of the infrared face. The LBP algorithm is synthesized to extract the overall LBP features by applying the innovation of chunking and layering of features. By analyzing and processing the infrared face image data from both visible and infrared face expression data, feature detection, feature extraction and effective classification of the four basic face expressions — happy, angry, disgusted and sad — are performed on the infrared images. The application of the algorithm is processed and improved accordingly to the characteristics of infrared face images, which improves the accuracy of recognition and classification compared to traditional methods.