SOLO-SLAM: A Parallel Semantic SLAM Algorithm for Dynamic Scenes.

Simultaneous localization and mapping (SLAM) is a core technology for mobile robots working in unknown environments. Most existing SLAM techniques can achieve good localization accuracy in static scenes, as they are designed based on the assumption that unknown scenes are rigid. However, real-world environments are dynamic, resulting in poor performance of SLAM algorithms. Thus, to optimize the performance of SLAM techniques, we propose a new parallel processing system, named SOLO-SLAM, based on the existing ORB-SLAM3 algorithm. By improving the semantic threads and designing a new dynamic point filtering strategy, SOLO-SLAM completes the tasks of semantic and SLAM threads in parallel, thereby effectively improving the real-time performance of SLAM systems. Additionally, we further enhance the filtering effect for dynamic points using a combination of regional dynamic degree and geometric constraints. The designed system adds a new semantic constraint based on semantic attributes of map points, which solves, to some extent, the problem of fewer optimization constraints caused by dynamic information filtering. Using the publicly available TUM dataset, SOLO-SLAM is compared with other state-of-the-art schemes. Our algorithm outperforms ORB-SLAM3 in accuracy (maximum improvement is 97.16%) and achieves better results than Dyna-SLAM with respect to time efficiency (maximum improvement is 90.07%).

La/LaF3 co-modified MIL-53(Cr) as an efficient adsorbent for the removal of tetracycline.

Chromium based metal-organic framework (MIL-53(Cr)) has enormous potential in the removal of organic contaminants from aqueous solutions due to its outstanding water stability, whereas its poor adsorption capacity limits the application. In this study, La/LaF3-MIL-53(Cr) was successfully synthesized by taking the advantages of La doping and LaF3 encapsulation with one-step hydrothermal method. Diverse analysis tools were utilized to verify that La not only existed in the framework, but also was loaded in the pores in the form of LaF3. The adsorption experiment results demonstrated that 0.3-La/LaF3-MIL-53(Cr) exhibited significantly improved adsorption capacity by four times compared with the pristine MIL-53(Cr) material. XPS and FTIR revealed that the affinity of La to tetracycline was significantly stronger than that of Cr and the excellent dispersion of LaF3 in the material may also be the cause of the increase in adsorption capacity. This study described a simple method to combine two different forms of modification and the modified material was potential for tetracycline adsorption.