No abstract

Current state-of-the-art two-stage detectors heavily rely on region proposals to guide the accurate detection for objects. In previous region proposal approaches, the interaction between different functional modules is correlated weakly, which limits or decreases the performance of region proposal approaches. In this paper, we propose a novel two-stage strong correlation learning framework, abbreviated as SC-RPN, which aims to set up stronger relationship among different modules in the region proposal task. Firstly, we propose a Light-weight IoU-Mask branch to predict intersection-over-union (IoU) mask and refine region classification scores as well, it is used to prevent high-quality region proposals from being filtered. Furthermore, a sampling strategy named Size-Aware Dynamic Sampling (SADS) is proposed to ensure sampling consistency between different stages. In addition, point-based representation is exploited to generate region proposals with stronger fitting ability. Without bells and whistles, SC-RPN achieves AR1000 14.5% higher than that of Region Proposal Network (RPN), surpassing all the existing region proposal approaches. We also integrate SC-RPN into Fast R-CNN and Faster R-CNN to test its effectiveness on object detection task, the experimental results achieve a gain of 3.2% and 3.8% in terms of mAP compared to the original ones.

No abstract

Developing a rapid and reliable method for measuring the photoreactivity of TiO2 pigments is of great importance for industrial application. The photoactivity of industrial TiO2 pigments were evaluated via the photodegradation of a model azo dye, methyl orange (MO), in the present work. The TiO2 pigments were characterized by Fourier-transform infrared spectroscopy (FTIR), ultraviolet–visible (UV–vis) spectroscopy, scanning electron microscopy (SEM), and photoluminescence (PL) spectroscopy. The photoactivity test results showed that the anatase TiO2 pigment was responsible for accelerating MO degradation, while the rutile pigment acted as a stabilizer, and effective UV absorber retarded the photodegradation of MO. It was found that the photodegradation of MO was driven mainly by photoholes (h+) and hydroxyl radicals (•OH), in the presence of TiO2 pigment with high photoactivity. With the help of the degradation intermediates during the photodegradation process and the calculated data, the preliminary degradation mechanism including azo bond cleaving, h+ oxidation, and hydroxylated products’ generation for MO was also elucidated. The photoactivity of TiO2 pigments can be rapidly evaluated in this work, which would be an efficient approach for assessing the product quality control and the end-use performance of TiO2 pigments.

No abstract

No abstract