Wuhan University of Technology

About: Wuhan University of Technology is a education organization based out in Wuhan, China. It is known for research contribution in the topics: Microstructure & Catalysis. The organization has 40384 authors who have published 36724 publications receiving 575695 citations. The organization is also known as: WUT.

Controllable synthesis of elliptical Fe3O4@C and Fe3O4/Fe@C nanorings for plasmon resonance-enhanced microwave absorption

Abstract: Heterostructured nanorings (NRs) with Fe3O4 and/or Fe cores and carbon shells (Fe3O4@C and Fe3O4/Fe@C) were synthesized by a facile and controllable two-step process. The NRs were formed through a synchronous reduction/carbonization/diffusion growth mechanism. Their composition, crystal size, and phase structure could be controlled by selecting the sintering temperature of iron glycolate nanosheets in the presence of acetone. Fe3O4/Fe@C NRs formed at 600 °C to 650 °C exhibit higher specific saturation magnetization (Ms) than Fe3O4@C NRs obtained at 300 °C to 500 °C because of increased Fe content and crystal size; the former also shows higher coercivity (Hc) because of large crystal size and surface pinning function. In addition, Fe3O4/Fe@C NRs show lower density and broader absorption bandwidth than Fe3O4@C NRs and Fe3O4 NRs. Fe3O4/Fe@C NRs formed at 600 °C with a mass fraction of 40 wt% exhibit an absorption bandwidth (RL ≤ −20 dB) of 6.7 GHz and a minimum RL value of −28.18 dB at 4.94 GHz. The enhanced absorption properties are ascribed to the heterostructured and ring-shape configuration, which generates multiple dielectric relaxations, enhanced electromagnetic parameters, and plasmon resonance absorption.

Fast image dehazing using improved dark channel prior

Abstract: In the frog and haze climatic condition, the captured picture will become blurred and the color is partial gray and white, due to the effect of atmospheric scattering. This situation brings a great deal of inconvenience to the video surveillance system, so the study of defogging algorithm in this weather is of great importance. This paper deeply analyzes the physical process of imaging in foggy weather. After full study on the haze removal algorithm of single image over the last decade, we propo se a fast haze removal algorithm which based on a fast bilateral filtering combined with dark colors prior. This algorithm starts with the atmospheric scattering model, derives a estimated transmission map by using dark channel prior, and then combines with grayscale to extract refined transmission map by using the fast bilateral filter. This algorithm has a fast execution speed and greatly improves the original algorithm which is morre time-consuming. On this basis, we analyzed the reasons why the image is dim after the haze removal using dark channel prior, and proposed the improved transmission map formula. Experimental-results show that this algorithm is feasible which effectively restores the contrast and color of the scene, significantly improves the visual effects of the image. Those image with large area of sky usually prone to distortion when using the dark channel prior, Therefore we propose a method of weakening the sky region, aims to improve the adaptability of the algorithm.

Multi-objective path planning for unmanned surface vehicle with currents effects.

Abstract: This paper investigates the path planning problem for unmanned surface vehicle (USV), wherein the goal is to find the shortest, smoothest, most economical and safest path in the presence of obstacles and currents, which is subject to the collision avoidance, motion boundaries and velocity constraints. We formulate this problem as a multi-objective nonlinear optimization problem with generous constraints. Then, we propose the dynamic augmented multi-objective particle swarm optimization algorithm to achieve the solution. With our approach, USV can select the ideal path from the Pareto optimal paths set. Numerical simulations verify the effectiveness of our formulated model and proposed algorithm.