- 标题
- 摘要
- 关键词
- 实验方案
- 产品
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Global MPPT of photovoltaic system based on scanning method under partial shading condition
摘要： The partial shading (PS) of the photovoltaic (PV) array is a major problem for the PV systems. Therefore, it is necessary to extract the global maximum power point (GMPP) under partial shading. In this paper, we propose a simple method to find the GMPP. This method scans the P–V curve and memorizes all the peaks in order to get the global peak. Next, we control a boost DC–DC converter to extract the GMPP from the PV system. In addition, this Method allows following the dynamic GP under variant SPs with less oscillations around the stable state compared to the existing works.
关键词： Scanning method,Photovoltaic system,Global maximum power point,PV string
更新于2025-09-23 15:21:01
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Applying Fast Scanning Method Coupled with Digital Image Processing Technology as Standard Acquisition Mode for Scanning Electron Microscopy
摘要： This study proposes an e?cient and fast method of scanning (e.g., television (TV) scan) coupled with digital image processing technology to replace the conventional slow-scan mode as a standard model of acquisition for general-purpose scanning electron microscopy (SEM). SEM images obtained using the proposed method had the same quality in terms of sharpness and noise as slow-scan images, and it was able to suppress the adverse e?ects of charging in a full-vacuum condition, which is a challenging problem in this area. Two problems needed to be solved in designing the proposed method. One was suitable compensation in image quality using the inverse ?lter based on characteristics of the frequency of a TV-scan image, and the other to devise an accurate technique of image integration (noise suppression), the position alignment of which is robust against noise. This involved using the image montage technique and estimating the number of images needed for the integration. The ?nal result of our TV-scan mode was compared with the slow-scan image as well as the conventional TV-scan image.
关键词： image integration,inverse filter,TV scan,charging effects,scanning electron microscopy,fast scanning method,digital image processing,slow-scan mode
更新于2025-09-23 15:19:57
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Laser Scanning Feedback Imaging System Based on Digital Micromirror Device
摘要： Most of the traditional scanning feedback imaging systems cannot break through the limitations of scanning speed. In this paper, a fast scanning system with changeable scanning sequences by projecting patterns alternatively on the digital micromirror device is proposed. Combined with the laser feedback techniques, the system exhibits high sensitivity to weak signals from targets with low reflectivity. In experiments, the images of handwriting ink patterns on a piece of glass are obtained in 6 seconds, and the resolution of the system is evaluated to be 124.5 μm with a 3.24mm by 3.24mm field of view. This scanning feedback imaging system can be combined potentially with single pixel imaging techniques to reconstruct phase objects more efficiently.
关键词： scanning method,laser feedback,imaging
更新于2025-09-16 10:30:52
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Effect of Er:YAG laser on debonding strength of laminate veneers
摘要： Objective: The purpose of this study was to evaluate the debonding strength of laminate veneers after using erbium?doped: yttrium aluminium garnet (Er:YAG) laser. Materials and Methods: A total of 60 bovine mandibular incisor teeth were divided into two groups (n = 30). Cylindrical specimens (0.7 mm × 5 mm) were fabricated from Empress II ceramic. Then, they were cemented to incisors using dual?cured resin cement (Variolink II). In the first group, no laser application was performed. The Er:YAG laser was applied on each laminate veneer at the test group for 9 s by using the scanning method. Shear force to remove the laminate veneers were applied with universal testing machine at a crosshead speed of 1 mm/min. Results: Results of this study exhibited significant differences between the control (27.28 ± 2.24 MPa) and test group (3.44 ± 0.69 MPa) (P < 0.05). Conclusion: This study shows that application of Er:YAG laser decreased the bond strength of laminate veneers.
关键词： Debonding,shear bond strength,scanning method,erbium-doped:yttrium aluminium garnet laser,laminate veneers
更新于2025-09-16 10:30:52
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A Two-stage Improvement Method for Robot Based 3D Surface Scanning
摘要： As known that the surface of unknown object was difficult to measure or recognize precisely, hence the 3D laser scanning technology was introduced and used properly in surface reconstruction. Usually, the surface scanning speed was slower and the scanning quality would be better, while the speed was faster and the quality would be worse. In this case, the paper presented a new two-stage scanning method in order to pursuit the quality of surface scanning in a faster speed. The first stage was rough scanning to get general point cloud data of object’s surface, and then the second stage was specific scanning to repair missing regions which were determined by chord length discrete method. Meanwhile, a system containing a robotic manipulator and a handy scanner was also developed to implement the two-stage scanning method, and relevant paths were planned according to minimum enclosing ball and regional coverage theories.
关键词： robotic manipulator,two-stage scanning method,3D laser scanning,handy scanner,surface reconstruction
更新于2025-09-11 14:15:04
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Millisecond-order X-ray phase tomography with a fringe-scanning method
摘要： We successfully realized millisecond-order X-ray phase tomography using a fringe-scanning method in grating-based X-ray interferometry. We obtained phase tomograms with a measurement time of 4.43 ms using a white synchrotron X-ray beam. The use of a fringe-scanning method enables us to achieve not only a higher spatial resolution but also a higher signal-to-noise ratio than that attained by the Fourier transform method. In addition, our approach can be applied to realize four-dimensional or high-throughput X-ray tomography for samples that can be rotated at a high speed.
关键词： fringe-scanning method,grating-based X-ray interferometry,white synchrotron X-ray beam,X-ray phase tomography,millisecond-order
更新于2025-09-10 09:29:36