A first and effective method is proposed to detect weld deject adaptively in various Dypes of real-time X-ray images obtained in different conditions. After weld extraction and noise reduction, a proper template of me...A first and effective method is proposed to detect weld deject adaptively in various Dypes of real-time X-ray images obtained in different conditions. After weld extraction and noise reduction, a proper template of median filter is used to estimate the weld background. After the weld background is subtracted from the original image, an adaptite threshold segmentation algorithm is proposed to obtain the binary image, and then the morphological close and open operation, labeling algorithm and fids＇e alarm eliminating algorithm are applied to pracess the binary image to obtain the defect, ct detection result. At last, a fast realization procedure jbr proposed method is developed. The proposed method is tested in real-time X-ray image,s obtairted in different X-ray imaging sutems. Experiment results show that the proposed method is effective to detect low contrast weld dejects with few .false alarms and is adaptive to various types of real-time X-ray imaging systems.展开更多
Mass imbalance-induced vibration affects the rotating machinery very large,especially the highspeed types.Off-line balancing techniques have been widely developed for rejecting unbalance-induced vibration but do not e...Mass imbalance-induced vibration affects the rotating machinery very large,especially the highspeed types.Off-line balancing techniques have been widely developed for rejecting unbalance-induced vibration but do not eliminate unbalanced vibration in the working state.Moreover,multiple start-stops are required in off-line balancing techniques.Therefore,research on an efficient electromagnetically-driven auto-balancer is carried out in the present work,and an internal excitation actuator is designed in this balancer.The electromagnetic characteristics of the two copper coil bobbins in the internal excitation actuator are compared and analyzed.The permanent magnets inside the actuator are simulated and analyzed with different sections of round,rectangular,and elliptical.And the results show that the elliptic type has the largest self-locking force.Finally,the dynamic balance test is performed on a test bench equipped with a designed electromagnetic balancing actuator,and the unbalance vibration is reduced from 130.23 μm to 5.98 μm.展开更多
文摘A first and effective method is proposed to detect weld deject adaptively in various Dypes of real-time X-ray images obtained in different conditions. After weld extraction and noise reduction, a proper template of median filter is used to estimate the weld background. After the weld background is subtracted from the original image, an adaptite threshold segmentation algorithm is proposed to obtain the binary image, and then the morphological close and open operation, labeling algorithm and fids＇e alarm eliminating algorithm are applied to pracess the binary image to obtain the defect, ct detection result. At last, a fast realization procedure jbr proposed method is developed. The proposed method is tested in real-time X-ray image,s obtairted in different X-ray imaging sutems. Experiment results show that the proposed method is effective to detect low contrast weld dejects with few .false alarms and is adaptive to various types of real-time X-ray imaging systems.
基金Supported by the National Natural Suience Foundation of China(No.51775030,91860126).
文摘Mass imbalance-induced vibration affects the rotating machinery very large,especially the highspeed types.Off-line balancing techniques have been widely developed for rejecting unbalance-induced vibration but do not eliminate unbalanced vibration in the working state.Moreover,multiple start-stops are required in off-line balancing techniques.Therefore,research on an efficient electromagnetically-driven auto-balancer is carried out in the present work,and an internal excitation actuator is designed in this balancer.The electromagnetic characteristics of the two copper coil bobbins in the internal excitation actuator are compared and analyzed.The permanent magnets inside the actuator are simulated and analyzed with different sections of round,rectangular,and elliptical.And the results show that the elliptic type has the largest self-locking force.Finally,the dynamic balance test is performed on a test bench equipped with a designed electromagnetic balancing actuator,and the unbalance vibration is reduced from 130.23 μm to 5.98 μm.
