No abstract

LiDAR-based pedestrian detection and tracking (PDT) with high-resolution sensing capability plays an important role in real-world applications such as security monitoring, human behavior analysis, and intelligent transportation. The problem of LiDAR-based PDT suffers from the complex gathering movements and the phenomenon of self- and inter-object occlusions. In this paper, the detection and tracking of dense pedestrians using three-dimensional (3D) real-measured LiDAR point clouds in surveillance applications is studied. To deal with the problem of undersegmentation of dense pedestrian point clouds, the kernel density estimation (KDE) is used for pedestrians center estimation which further leads to a pedestrian segmentation method. Three novel features are defined and used for further PDT performance improvements, which takes advantage of the pedestrians’ posture and body proportion. Finally, a new track management strategy for dense pedestrians is presented to deal with the tracking instability caused by dense pedestrians occlusion. The performance of the proposed method is validated with experiments on the KITTI dataset. The experiment shows that the proposed method can significantly increase F1 score from 0.5122 to 0.7829 compared with the STM-KDE. In addition, compared with AB3DMOT and EagerMOT, the tracking trajectories from the proposed method have the longest average survival time of 36.17 frames.

In this study, cherry tomatoes were selected as research objects, and the characteristics of sensory indicators, nutrition indicators, physiological and biochemical indicators, microbial indicators and harmful chemical substances were selected during the shelf life. Finally, the key evaluation indicators and indicators were determined by SPSS software analysis. The establishment of a cherry tomato quality evaluation system provides a theoretical basis for extending the shelf life of cherry tomatoes. The evaluation system was as follows: principal component 1=-0.472578778 sensory +0.451205869 total colony +0.453105683 weight loss rate -0.434582494 hardness +0.422708656 lycopene. This study has positive significance on the preservation of cherry tomato.

In order to evaluate the safety of trifloxystrobin in environment and non-target organisms, the enrichment and distribution of trifloxystrobin in Medaka (Oryzias latipes) were studied in this experiment. Medaka were exposed in the water containing 0.