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关键词： 差分互感式传感器   振动监测   变压器故障诊断  

摘要： 阐述一种基于差分互感式传感器的变压器振动监测技术，介绍其结构设计、工作原理和等效电路模型。通过仿真案例验证，该系统具有高测量精度、强抗干扰能力和高灵敏度等特点，能够在恶劣环境下有效捕捉振动信号，为变压器状态监测与维护提供技术支持。

关键词： 压水堆机组   寿期末   轴向功率   偏差   稀释   硼化  

摘要： 针对现有技术在核电站压水堆寿命终期堆芯轴向功率偏差控制问题上存在的不足,导致堆芯轴向功率偏离较大,难以实现预期控制目标,本项目拟开展核电压水堆寿命终期堆芯轴向功率偏差的控制方法研究。本文在寿终时刻,利用堆芯的上部功率和下部功率,监控堆芯的轴向功率偏差。偏差值为正值,在寿终期压水堆机组采用稀释升功率的方式降低堆芯的轴向功率偏差;偏差值为负值,在寿终期压水堆机组采用硼化降功率的方式提升堆芯的轴向功率。经实验证明,设计技术应用下堆芯轴向功率偏差不超过±0.5%,能够有效将其控制在规定范围内,确保核电厂压水堆机组寿期末安全可靠运行。

关键词： 3维功率分布   堆芯在线监测   本征正交分解   径向基函数插值   反应堆堆芯  

摘要： 堆芯3维功率分布的在线监测对于确保反应堆的安全运行至关重要。为此，核电厂部署了堆内和堆外探测器，以获取必要的测量数据。通过利用相关测量信息，并结合适当正交分解(proper orthogonal decomposition, POD)进行模型降阶和径向基函数(radial basis function,RBF)插值，可以实现堆芯功率分布的实时测量。本文利用PCM软件包实现某压水堆某燃料循环约7 000个堆芯状态的模拟，并实现从模拟的探测器信号到模拟的堆芯3维功率分布的映射模型构建。结果表明，该方法能够有效处理高维数据，提取主要特征，从而提高3维功率分布监测计算的效率和准确性。通过引入测量值的扰动，展示了POD-RBF模型的稳健性，表明该模型在面对不确定性时仍能保持良好的性能。同时，本文提出了一种基于测量探测器信号的白噪声或失效扰动方法，显著增强了POD-RBF方法的稳定性。相关结果为未来的核能监测技术奠定了基础，推动了相关领域的进一步研究与发展。

关键词： 差分进化算法   功率分配   退火炉   数学模型  

摘要： 针对退火炉加热段的功率分配问题，在差分进化算法和非支配排序算法的基础上，加入目标优先级的控制策略，并与不加入优先级控制策略算法的结果进行比较。结果表明：改进算法可有效解决退火炉加热段的功率分配问题，在满足带钢出口温度在允许范围内的条件下，其总的有效加热功率最小；进行功率分配的加热总功率小于不进行功率分配的总加热功率，且二者的差距随着目标允许误差的减小而增大；在允许误差为±5℃时，进行功率分配的总加热功率可以减小0.5%，节能效果较为显著。

关键词： MOSFET   High-k dielectric materials   Electric fields   Split gate flash memory cells   Logic gates   Fabrication   Switches   Performance evaluation   Impact ionization   Doping   Breakdown voltage   figure of merit   high-k materials   power density   specific on-resistance   SGT-MOSFET   superjunction   switching time   TCAD  

摘要： In this paper, we propose a simulation-based novel Split-Gate Trench MOSFET structure with an optimized fabrication process to enhance power efficiency, switching speed, and thermal stability for high-performance semiconductor applications. Integrating High-k pillars Superjunction beneath the Split-Gate enhancing breakdown performance by reducing critical field intensity by up to 35%, the device achieves a 15% improvement in Figures of Merit (FOMs) for $\mathrm {BV}<^>{2}/R_{\mathrm {on,sp}}$ . Dynamic testing reveals approximately a 25% reduction in both input and output capacitance, as well as gate-drain charge ( $Q_{\text {GD}}$ ). This reduction, coupled with an approximately 40% improvement in Baliga's High-Frequency Figure of Merit (BHFFOM) and over 20% increase in the New High-Frequency Figure of Merit (NHFFOM), underscores the design's suitability for high-speed, high-efficiency power electronics. Simulations examining the effects of High-k pillar depth indicate that an optimal depth of $3.5 \;\mu $ m achieves a balanced performance between BV and $R_{\text {on,sp}}$ . The influence of High-k materials on BT-Hk-SJ MOSFET performance was investigated by comparing hafnium dioxide (HfO2), nitride, and oxynitride. Among these, HfO2 demonstrated optimal performance across static, dynamic, and diode characteristics due to its high dielectric constant, while material choice had minimal impact, with variations kept within 5%.

关键词： 硬件支持   可穿戴设备   计算机视觉   剪枝策略   大规模数据集   人工智能   非结构化   自适应滤波器  

摘要： 1背景随着人工智能的快速发展和大规模数据集的普及，卷积神经网络（CNN）在计算机视觉领域的应用日益广泛。尽管大型CNN模型能提供丰富的信息表示，但在资源有限的移动设备和可穿戴设备上部署时面临显著挑战。因此，有效轻量化深度CNN模型成为当前研究的重要方向。网络剪枝是一种模型简化技术，通过删除冗余滤波器来降低复杂度。剪枝方法主要分为结构化剪枝和非结构化剪枝。非结构化剪枝以参数为单位进行操作，通常需要特定硬件支持才能显著加速；而结构化剪枝则以通道或滤波器为单位，能在无特殊硬件支持的情况下实现模型加速，因此受到广泛关注。

关键词： 隔离DC-DC转换器   无磁芯微型变压器   转换效率   模拟集成电路设计  

摘要： 设计了一种采用GSMC 0.35μm BCD工艺制作的基于无磁芯微型变压器的高效率隔离式DC-DC转换器。分析了无磁芯微型变压器的线宽、内径、线间距、圈数以及原副线圈的间距对隔离DC-DC转换器效率的影响,并将EMX建模与仿真数据结果最优的一组无磁芯微型变压器模型应用到该隔离DC-DC转换器中,最后选择最优的编码与解码方案,进一步提高该转换器转换效率。仿真结果表明,在工作频率为180 MHz、输入电源电压为5 V、输出5 V隔离电压时,该隔离DC-DC转换器输出电流范围为0～120 m A,最大输出功率为600 m W,且最高转换效率达到40%。

关键词： MOSFET   Stability criteria   Circuit stability   Noise   Current measurement   Voltage   Thermal stability   Resistors   Force measurement   Standards   Electromagnetic force   joule balance   kilogram realization   stable current source (CS)   voltage-controlled CS (VCCS)  

摘要： In the joule balance method to realize the kilogram, a programmable current source (CS) is necessary to produce a stable electromagnetic force to balance the Earth's gravitational force on the mass. The stability and noise level of the current strongly determine the statistical uncertainty introduced by the force measurement phase in the joule balance. An approach to implement a CS with high stability and low noise by a method of two-stage current parallel summation is presented here, with which the CS can be coarsely and finely tuned separately by two subsystems. Based on this idea, a programmable CS with high stability and low noise has been developed. The output current range is from 0 to 14 mA with a resolution of 3.5 nA. The experimental results show that the stability of the current is better than 0.15 (mu A/A)/h at 5 mA, which meets the requirement of the joule balance.

关键词： SRAM cells   Transistors   MOSFET   Delays   Noise   Power demand   Voltage   Monte Carlo methods   Driver circuits   Wireless sensor networks   Area efficient   design optimization   leakage current   low latency   Monte Carlo analysis   power efficient   static noise margin (SNM) analysis  

摘要： Performance optimization is a crucial aspect of enhancing the efficiency of electronic systems, and scaling is a primary method for achieving optimal performance while maintaining the integrity of system architecture. This paper introduces a novel algorithm for optimizing transistor sizing in static random-access memory (SRAM) to enhance speed, improve Static Noise Margin (SNM), and reduce leakage power consumption. The SRAM is designed using 45 nm technology and operates at a supply voltage of 1.2 V. To validate the algorithm's effectiveness, Monte Carlo simulations were conducted under varying process, voltage, and temperature conditions. The results demonstrate read access times of 11.17 ps (HIGH) and 9.97 ps (LOW), and write access times of 12.00 ps (HIGH) and 17.00 ps (LOW). The measured SNM values for the read, write, and hold states were 328.2 mV, 453.7 mV, and 452.3 mV, respectively. The inclusion of precharge and write driver circuits allows for a compact SRAM layout, occupying 9.79 mu m(2), with the SRAM cell itself occupying 4.1 mu m(2). Furthermore, the proposed SRAM design exhibits low leakage power consumption of 1.64 pW, demonstrating the efficiency and performance benefits of the optimized transistor sizing approach.

关键词： Power MOSFET  

摘要： Regular removal of thin film depositions from vapor deposition chambers is a critical step in semiconductor manufacturing processes, directly impacting the efficiency and quality of production. Traditional manual disassembly cleaning methods have several drawbacks, including the necessity for shutdown operations, cooling treatment and breaking the vacuum, all of which consume considerable time and disrupt the production process. In contrast, plasma cleaning causes less damage to the chamber interior and has therefore become the preferred cleaning method. However, maintaining plasma stability requires a drive power supply with consistent current and frequency to prevent plasma extinction. In this article, the electrical characteristics of the drive power supply for the plasma generation device (PGD) are discussed, considering its dynamic and nonlinear load characteristics of plasma. Through analysis of the equivalent circuit, the condition of current gain equal to 1 is analyzed, thereby achieving the constant-current output. A Power MOSFET-based test platform was established and experimental results validate the effectiveness of the analysis. © 1988-2012 IEEE.