Precision machining fields often require worktables with different stroke sizes. To address the need for scalability and facilitate manufacturing, this study proposes a novel infinite expansion magnetically levitated planar motor (MLPM) based on PCB stator coils. Different from existing magnetic levitation systems that use PCB coils, the design presented in this paper utilizes smaller coil units, with each coil being independent of one another.
View Article and Find Full Text PDFIn this paper, an iterative neural network adaptive robust control (INNARC) strategy is proposed for the maglev planar motor (MLPM) to achieve good tracking performance and uncertainty compensation. The INNARC scheme consists of adaptive robust control (ARC) term and iterative neural network (INN) compensator in a parallel structure. The ARC term founded on the system model realizes the parametric adaptation and promises the closed-loop stability.
View Article and Find Full Text PDFThe magnetic levitation system has been considered as a promising actuator in micromachining areas of study. In order to improve the tracking performance and disturbance rejection of the magnetically levitated rotary table, an iterative learning PID control strategy with disturbance compensation is proposed. The estimated disturbance compensates for the control signals to enhance the active disturbance rejection ability.
View Article and Find Full Text PDFResidential-level short-term load forecasting (STLF) is significant for power system operation. Data-driven forecasting models, especially machine-learning-based models, are sensitive to the amount of data. However, privacy and security concerns raised by supervision departments and users limit the data for sharing.
View Article and Find Full Text PDFGuang Pu Xue Yu Guang Pu Fen Xi
February 2017
We propose a laser rangefinder system based on the quadrature modem to achieve amplitude modulation, the method improves the accuracy of the phase measuring and simplifies the hardware design compared to the system with the secondary mixing methods, and to solve the range ambiguity caused by the measuring process, the ranging ambiguity resolving algorithm based on the over-determined equation is proposed, which avoids the searching of the optimal solution, finally the two K60 laser rangefinders and three proposed rangefinders were experimented on the national standard baseline with the precision of 0.18 mm. the measuring time of the proposed system is less than 1.
View Article and Find Full Text PDFJ Med Ultrason (2001)
January 2015
Purpose: As a key technology in high-intensity focused ultrasound (HIFU) ablation systems, a precise ultrasound image segmentation method for tumor boundary detection is helpful for ablation of tumors and avoiding tumor recurrence. This study explores a new deformable snake model called multi-scale generalized gradient vector flow (MS-GGVF) to segment ultrasound images in HIFU ablation.
Methods: The main idea of the technique is dealing with two issues including spurious boundary attenuation and setting the standard deviation of the Gaussian filter.
Target segmentation in ultrasound images is a key step in the definition of the intro-operative planning of high-intensity focused ultrasound therapy. This paper presents an improvement for the balloon snake in segmentation. A sign function, designed by the edge map and the moving snake, is added to give the direction of the balloon force on the moving snake separately.
View Article and Find Full Text PDFGuang Pu Xue Yu Guang Pu Fen Xi
August 2012
The performance of the uniform motion of the moving mirror, which is the only constant motion part in FTIR spectrometer, and the performance of the alignment of the fixed mirror play a key role in FTIR spectrometer, and affect the interference effect and the quality of the spectrogram and may restrict the precision and resolution of the instrument directly. The present article focuses on the research on the uniform motion of the moving mirror and the alignment of the fixed mirror. In order to improve the FTIR spectrometer, the maglev support system was designed for the moving mirror and the phase detection technology was adopted to adjust the tilt angle between the moving mirror and the fixed mirror.
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