分类: 物理学 >> 普通物理:统计和量子力学,量子信息等 提交时间: 2023-09-05
摘要: To enhance the accuracy of 2 and 2 particle surface emission rate measurements and address the identification issues of nuclides in conventional methods, this study introduces two artificial neural network (ANN) algorithms: back propagation (BP) and genetic algorithm-based back propagation (GA-BP). These algorithms classify pulse signals from distinct and particles. Their discrimination efficacy is assessed by simulating standard pulse signals and those produced by contaminated sources, mixing and particles within the detector. This study initially showcases energy spectrum measurement outcomes, subsequently tests the ANNs on the measurement and validation datasets, and contrasts the pulse shape discrimination efficacy of both algorithms. Experimental findings reveal that the proportional counter's energy resolution is not ideal, thus rendering energy analysis insufficient for distinguishing between 2 and 2 particles. The BP neural network realizes approximately 99% accuracy for 2 particles and approximately 95% for 2 particles, thus surpassing the GA-BP's performance. Additionally, the results suggest enhancing particle discrimination accuracy by increasing the digital acquisition card's threshold lower limit. This study offers an advanced solution for the 2 and 2 surface emission rate measurement method, presenting superior adaptability and scalability over conventional techniques.
分类: 物理学 >> 普通物理:统计和量子力学,量子信息等 提交时间: 2017-05-02
摘要: The composite NdFeB magnets with blending melt-spun flakes and Fe fine powders were prepared by the hot-pressed and hot-deformed route. Characterizations of the hot-deformed NdFeB magnets affected by the doped Fe powders were tested. The doped Fe powders decrease the hot-deformed pressure when the strain is between 15 and 50%. XRD patterns show that the doped Fe powders have little influence on the c-axis alignment of hot-deformed NdFeB magnets in the press direction. The Br and the (BH)max get improved when the doped Fe powders are less than 3 wt%. The doped Fe of hot-deformed NdFeB magnets exists in the elongated state and the spherical state surrounded by the Nd-rich phase. With the Fe fraction increasing, the potential of magnet moves to the positive direction and the diameter of the Nyquist arc becomes larger, which indicate that the corrosion resistance improved effectively. The bending strength was enhanced by the elongated α-Fe phase embedded in the matrix 2:14:1 phase.