Grayscale image processing is a key research area in the field of computer vision and image analysis, where image quality and visualization effects may be seriously damaged by high-density salt and pepper noise. A traditional median filter for noise removal may result in poor detail reservation performance under strong noise and the judgment performance of different noise characteristics has strong dependence and rather weak robustness. In order to reduce the effects of high-density salt and pepper noise on image quality when processing high-noise grayscale images, an improved two-dimensional maximum Shannon entropy median filter (TSETMF) is proposed for the adaptive selection of a threshold to enhance the filter performance while stably and effectively retaining the details of the images. The framework of the proposed improved TSETMF algorithm is designed in detail. The noise in images is filtered by means of automatically partitioning a window size, the threshold value of which is adaptively calculated using two-dimensional maximum Shannon entropy. The theoretical model is verified and analyzed through comparative experiments using three kinds of classical grayscale images. The experimental results demonstrate that the proposed improved TSETMF algorithm exhibits better processing performance than that of the traditional filter, with a higher suppression of high-density noise and denoising stability. This stronger ability while processing high-density noise is demonstrated by a higher peak signal-to-noise ratio (PSNR) of 24.97 dB with a 95% noise density located in the classical Lena grayscale image. The better denoising stability, with a noise density from 5% to 95%, is demonstrated by the minor decline in the PSNR of approximately 10.78% relative to a PSNR of 23.10 dB located in the classical Cameraman grayscale image. Furthermore, it can be advanced to promote higher noise filtering and stability for processing high-density salt and pepper noise in grayscale images.

For the complexity of accidents occurredat the intersections, a temporal-spatial collision warning method was proposed. On the basis of vehicle's passing time of the conflict zone, the algorithm calculated probability of accident was established. Due to the deficiencies of considering time coordinate only, spatial coefficient which represented the relationship between actual distance and safety braking distance was used to correct the algorithm. A two-way and two-lane intersection was taken as an example. The drivers were divided into three categories: normal, negative and positive. Finally, special warning method was used to remind different kinds of drivers to avoid accidents. The results illustrated that the system should warn the negative drivers earlier and a delay warning measure should be taken for positive drivers

Motion control of UAVs is an interesting problem due to the nonlinear and underactuacted nature of their dynamics. This paper focuses on position and yaw control of a rotary-wing UAV with state and input constraints using an inner-outer loop control structure. The outer loop generates saturated thrust and reference roll and pitch angles, while the inner loop is designed to follow the reference angles based on a Proportional-Derivative (PD) controller. In the outer loop, a smooth nested saturation controller is designed and proven to be asymptotically stable. A simulation based on the indoor ANCL (Applied Nonlinear Control Lab) quadrotor platform at University of Alberta is used to demonstrate the performance of the proposed controller.

Aiming at the problems of lack of data on the nonlinear morphology to divide uneven grain boundary in bulk ceramics, a unique approach of nanorobot-based characterization of three-dimensional nonlinear structure length can be creatively proposed under scanning electron microscope to quantify the actual morphology of local micro-area grain boundary in bulk ZnO. Contour shapes of the targeted grain boundaries in plane X-Y can be imaged using SEM. Z-directional relative height differences at different positions can be sequentially probed by nanorobot. Experiments demonstrate that it is effective to characterize three-dimensional length structures of nonlinear grain boundaries in bulk materials. By quantifying Z-directional relative height differences, it can be verified to show that irregular characteristics exist in three-dimensional grain boundary length, which can extend the depth effect on nonlinear bulk conductance. Furthermore, this method can also obtain nonlinear quantitative topographies to divide grain boundaries to uneven structure in the analysis of bulk polycrystalline materials.

Flexible screen possessing a high-contrast ratio to accomplish high-definition display can be attributed to the accuracy of polarizer assembly. Different from the existing polarizer attached onto a flexible screen, resulting in low-accuracy and nonalignment attaching behaviors, a unique approach of underactuated bionic scorpion robot arms can be developed to explore the stable capture and accurate alignment motion operations. Overall structure design and D–H kinematic simulation of bionic scorpion robot arm can be conducted to analyze virtual three-key typical motions. Motion optimization of structural parameters and corresponding motion workspaces verification can be adopted to evaluate motion range and ability. Experiments can be utilized to verify the rationality of theoretical modeling and optimization simulation of bionic scorpion robot arm. Experimental results illustrate that it is evident to demonstrate that the motion behaviors of bionic scorpion robot arm can be verified to be consistent with three key states of virtual theoretical motions. The key joints possessing minor errors may also be utilized to illustrate the relatively excellent dynamic motions existing in bionic scorpion robot arm. Further, advancing the stable motion behaviors of bionic scorpion robot arm may solve the problems of low-accuracy and misalignment polarizer attachments.