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Motion object detection (MOD) with freely moving cameras is a challenging task in computer vision. To extract moving objects, most studies have focused on the difference in motion features between foreground and background, which works well for dynamic scenes with relatively regular movements and variations. However, abrupt illumination changes and occlusions often occur in real-world scenes, and the camera may also pan, tilt, rotate, and jitter, etc., resulting in local irregular variations and global discontinuities in motion features. Such complex and changing scenes bring great difficulty in detecting moving objects. To solve this problem, this paper proposes a new MOD method that effectively leverages local and global visual information for foreground/background segmentation. Specifically, on the global side, to support a wider range of camera motion, the relative inter-frame transformations are optimized to absolute transformations referenced to intermediate frames in a global form after enriching the inter-frame matching pairs. The global transformation is fine-tuned using the spatial transformer network (STN). On the local side, to address the problem of dynamic background scenes, foreground object detection is optimized by utilizing the pixel differences between the current frame and the local background model, as well as the consistency of local spatial variations. Then, the spatial information is combined using optical flow segmentation methods, enhancing the precision of the object information. The experimental results show that our method achieves a detection accuracy improvement of over 1.5% compared with the state-of-the-art methods on the datasets of CDNET2014, FBMS-59, and CBD. It demonstrates significant effectiveness in challenging scenarios such as shadows, abrupt changes in illumination, camera jitter, occlusion, and moving backgrounds. [ABSTRACT FROM AUTHOR]

To enhance the microhardness and wear resistance of low-carbon steel, laser cladding was employed to create A100-Y2O3 cladding coatings that remained free of cracks. The phase composition, microstructure, and element distribution of these coatings were examined using XRD and SEM analyses, respectively. The microhardness and wear resistance of the A100-Y2O3 cladding coatings were tested by an HXS-1000 A type digital liquid crystal intelligent microhardness tester and an ML-10 friction and wear tester, respectively. The XRD results show that the addition of Y2O3 did not change the phase composition of the A100-Y2O3 cladding coatings. With the addition of Y2O3, the grains of the A100-Y2O3 cladding coatings are finer compared with those of the A100-0%Y2O3 cladding coating. The upper part of the A100-Y2O3 cladding coatings were composed of fine equiaxed grains. The average microhardness of the A100-0%Y2O3 cladding coatings was 532.489 HV. With the addition of Y2O3, the microhardness of the A100-Y2O3 cladding coatings was obviously improved, and the average microhardness of A100-1.5%Y2O3 coating reached 617.290 HV. The A100-Y2O3 cladding coatings were reduced, and the worn surface became relatively smooth owing to the addition of Y2O3. The addition of Y2O3 significantly improved the wear resistance of the A100-Y2O3 cladding coatings. [ABSTRACT FROM AUTHOR]

Veterinary drugs originally used to diagnose, prevent, control and treat animal diseases. However, now some of them can also be mixed into livestock feed as growth promoters. Although most countries have specified animal-derived veterinary drug residue standards, such as the maximum residue limit, withdrawal period and prohibition of some veterinary drugs as growth promoters, there are still some animal-derived products with illegal amount of drug residues. Consequently, long-term intake of products with excessive residues will result in irreversible impacts on human health, livestock industries and natural environment. To minimize these risks, the techniques of drug residues detection plays an important role in guarding food safety of animal products. Moreover, Veterinary drug residue detection technology, according to the author's opinion, can be divided into instrumental method, immunoassay method, biomolecular technology and bio-sensor technology. The purpose of this article is to collect and summarize the existing journal literature current about status, hazards and detection techniques of animal-origin veterinary drug residues so that ordinary readers can briefly understand the research status of the residue detection techniques, farmers can understand the importance of regulating and suitable handling of veterinary drugs, and relevant researchers may know about the emphasized difficulties that need to be overcome in drug residue detection techniques.

The waveguide structure made of lithium niobate crystal (LiNbO3, LN) can further improve the device integration. It has been widely used in electro-optical modulator, frequency conversion, acousto-optic Q-switching and other optoelectronic devices. It has important application prospects in optical fiber communication, photoelectric sensing, lidar, aerospace and other fields. The LN waveguide made by traditional Ti diffusion method has poor resistance to photorefractive damage in short wave applications. The LN waveguide made by annealing proton exchange method only support TM mode (transverse magnetic mode) single polarization transmission, and its application field is limited. In this paper, a new Zn diffusion method is proposed to fabricate magnesium doped LN ridge waveguide. By establishing the diffusion model and simulation of the waveguide, the technological conditions were explored and tested. The lowest transmission loss of LN waveguide is 0.86 dB/cm, and the photorefractive damage threshold can reach 184 kW/cm². It will provide a better preparation way for the research and development of high power lithium niobate waveguide integrated optoelectronic devices. [ABSTRACT FROM AUTHOR]