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Plastic products are a significant component of the manufacturing industry and the plastic industry is closely related to economic and social development. As constraints from resources and environment tighten, rational disposal and utilization of waste plastics becomes crucial for the sustainable economic and environmental development. Currently, the variety of plastic products becomes abundant, and disposal technologies and application challenges are constantly updated. Considering the demand for highquality development of the industry and increasingly strict environmental protection requirements, a systematic analysis of the research progress of waste plastic disposal and utilization becomes urgent. In this study, the waste plastic disposal and utilization technologies are categorized into mechanical disposal of waste plastics, energy and resource conversion, regeneration recycling, and new technologies for disposal and utilization. These four types of technologies are expounded from the aspects of technical features, applicable conditions, and research progress. On the basis, facing the technical challenges and referring to the existing experience of developed countries, suggestions are proposed from the aspects of source reduction, sorted recycling of waste plastics, and technological innovation and transformation, hoping to provide a reference for the clean disposal and recycling of waste plastics in China.

Synthetic aperture radar (SAR) is a high-resolution imaging radar. With the deteriorating electromagnetic environment, SAR systems are susceptible to various forms of electromagnetic interference, including deception jamming. This jamming notably impacts SAR signal processing and subsequently worsens the quality of acquired images. Chaotic frequency modulation (CFM) signals could effectively counteract deception jamming. Nevertheless, due to the inadequate band-limited performance of CFM signals, higher oversampling factors are needed for achieving optimal low sidelobe levels, leading to increased system costs and excessively high data rates. Additionally, not all chaotic sentences meet the CFM signal requirements. In response, this paper proposes a novel signal modulation method called chaotic-nonlinear frequency modulation (C-NLFM) that enhances band-limited performance. The optimum parameters for C-NLFM signals are selected using the particle swarm optimization (PSO) algorithm. In this way, C-NLFM signals attain ideal low sidelobe levels even when faced with reduced oversampling factors. Meanwhile, this chaotic coding mode retains its capability to effectively suppress deception jamming. Moreover, C-NLFM signals demonstrate versatility in adapting to various chaotic sequences, thereby enhancing their flexibility to modify the signals as required. Through comprehensive simulations, data analysis, and a semi-physical experiment, the effectiveness and superiority of this proposed method have been confirmed. [ABSTRACT FROM AUTHOR]

Orthodontic treatment monitoring involves using current images and previous 3D models to estimate the relative position of individual teeth before and after orthodontic treatment. This process differs from image-based object 6D pose estimation due to the gingiva deformation and varying pose offsets for each tooth during treatment. Motivated by the fact that the poses of molars remain relatively fixed in implicit orthodontics, we design an approach that employs multiview pose evaluation and bidirectional temporal propagation for jaw pose estimation and then employs an iteration-based method for tooth alignment. To handle changes in tooth appearance or location with weak texture across frames, we also introduce an instance propagation module that leverages positional and semantic information to explore instance relations in the temporal domain. We evaluated the performance of our approach using both the Shining3D tooth pose dataset and the Aoralscan3 tooth registration dataset. Our experimental results demonstrate remarkable accuracy improvements compared with existing methods. [ABSTRACT FROM AUTHOR]