在压水堆冷却剂丧失事故（Loss-of Coolant Accident，LOCA）中，处于高温条件下的燃料棒由于棒内压力过高，可能导致包壳发生鼓胀。包壳形变会造成堆芯局部流道堵塞，进而影响失水事故再淹没阶段的堆芯换热。然而，大多数系统分析程序都是基于假设的流道堵塞率来模拟事故进程，导致模拟结果与实际情况不符合。本文将已开发的燃料棒热-力行为分析模块（Fuel Rod Thermal-Mechanical Behavior，FRTMB）集成在自主开发的严重事故分析程序ISAA（Integrated Severe Accident Analysis Code）中，通过改进已有的流道堵塞模型，使其能够模拟由于燃料棒形变导致的冷却剂流量变化。最后，使用ISAA-FRTMB模拟QUENCH-LOCA-0实验，通过对比包壳峰值温度，验证改进的流道堵塞模型的正确性和有效性，并在此基础上研究包壳形变对堆芯换热以及后续事故进程的影响。

印刷电路板上连接PIN正位度检测是保证PCB电气可靠性的重要环节，其主要检测PIN缺针、共线度与高度。为满足生产实际需求，提出一种基于双目视觉的连接PIN正位度检测方法。首先，通过双目标定获取相机内外参数，实现图像立体校正；其次，根据先验的相对方位和给定的排列信息生成相应的栅格，基于栅格灰度阈值变化进行PIN缺失检测；然后，分别提取PIN在两个相机视野中对应的特征角点，基于视差原理进行针尖三维坐标计算，实现对PIN的排列共线度检测；最后，提出了基于特征提取的PIN相对高度检测方法，实现了对PIN的相对高度检测。实验结果验证了所提方法的有效性，PIN相对高度检测的平均耗时为125.4 ms，精度达99.535%，重复性精度在±0.05 mm内。

Whispering gallery mode (WGM) microcavities have been widely used for high-sensitivity ultrasound detection, owing to their optical and mechanical dual-resonance enhanced sensitivity. The ultrasound sensitivity of the cavity optomechanical system is fundamentally limited by thermal noise. In this work, we theoretically and experimentally investigate the thermal-noise-limited sensitivity of a WGM microdisk ultrasound sensor and optimize the sensitivity by varying the radius and a thickness of the microdisk, as well as using a trench structure around the disk. Utilizing a microdisk with a radius of 300 μm and thickness of 2 μm, we achieve a peak sensitivity of 1.18μPaHz-1/2 at 82.6 kHz. To the best of our knowledge, this represents the record sensitivity among cavity optomechanical ultrasound sensors. Such high sensitivity has the potential to improve the detection range of air-coupled ultrasound sensing technology.

为了实现高精度连续探测对流层和平流层大气风场，搭建了一台直接测风激光雷达系统对对流层和平流层大气风场进行探测。该系统基于双边缘法布里-珀罗标准具的瑞利散射多普勒测风原理，使用转台式探测结构，通过频率跟踪的手段对频率漂移进行跟踪，确保测风的精度。实验结果表明，该系统对对流层和平流层大气风场探测效果良好，频率跟踪的范围为±50 MHz，可以大大减小频率漂移带来的风速误差。经过系统的稳定运行和长时间的观测，在40 km处测得的径向风速随机误差为8 m/s。径向风速合成为水平风速后，随机误差在38 km处最大为10 m/s左右。该系统白天探测高度为25 km，夜晚探测高度为38 km。与探空数据对比，风速误差均小于10 m/s，其中风速误差在±5 m/s的范围内的数据量约占75.8%，探测的风向误差与探空气球的趋势基本一致，误差范围在10°~20°之间，在15°范围内的数据量约占58.6%。将实测数据与探空数据进行统计分析，结果具有良好的一致性。该系统可以为对流层和平流层大气风场的探测提供数据支撑。

Three-dimensional chiral materials with intrinsic chirality play a crucial role in achieving a strong chiral response and flexible light manipulation. Reconfigurable chirality through the 3D morphological transformation of chiral materials is significant for greater freedom in tailoring light but remains a challenge. Inspired by the unique 3D morphological memory capability of shape memory alloys (SMAs), we demonstrate and discuss a chiral resonator in the microwave regime that can realize reconfigurable chirality through 3D morphological transformation. The introduction of heating film realizes voltage control of SMA’s morphology for utilizing the temperature sensitivity of SMA better, enabling arbitrary control of circular dichroism (CD) flip and CD intensity. The qualitative and quantitative analysis of the surface current distribution of chiral enantiomers reveals that the chirality of meta-atoms originates from the surge of electric dipole px and electric quadrupole Q. It is worth mentioning that the proposed strategy to achieve reconfigurable chirality using 3D morphological transformations can be directly extended to other higher frequencies, such as visible, infrared, and terahertz bands. Significantly, our paradigm to study the relationship between complex 3D morphology and chirality holds potential for application in biosensing, spin detection, and spin-selective devices.

Noble metallic nanostructures with strong electric near-field enhancement can significantly improve nanoscale light–matter interactions and are critical for high-sensitivity surface-enhanced Raman spectroscopy (SERS). Here, we use an azimuthal vector beam (AVB) to illuminate the plasmonic tips circular cluster (PTCC) array to enhance the electric near-field intensity of the PTCC array, and then use it to improve SERS sensitivity. The PTCC array was prepared based on the self-assembled and inductive coupled plasmon (ICP) etching methods. The calculation results show that, compared with the linearly polarized beam (LPB) and radial vector beam excitations, the AVB excitation can obtain stronger electric near-field enhancement due to the strong resonant responses formed in the nanogap between adjacent plasmonic tips. Subsequently, our experimental results proved that AVB excitation increased SERS sensitivity to 10^-13 mol/L, which is two orders of magnitude higher than that of LPB excitation. Meanwhile, the PTCC array had excellent uniformity with the Raman enhancement factor calculated to be ∼2.4×108. This kind of vector light field enhancing Raman spectroscopy may be applied in the field of sensing technologies, such as the trace amount detection.

针对相机抖动、拍摄物体快速运动以及低快门速度等因素造成的图像非均匀模糊，提出一种结合多尺度特征融合和多输入多输出编-解码器的去模糊算法。首先使用多尺度特征提取模块来提取较小尺度模糊图像的初始特征，该模块使用扩张卷积来以较少的参数量获得更大的感受野。其次，通过特征注意力模块来自适应地学习不同尺度特征中的有效信息，该模块利用小尺度图像的特征来生成注意图，能够有效地减少冗余特征。最后，使用多尺度特征渐进融合模块逐步融合不同尺度的特征，使得不同尺度特征信息能够进行互补。相比以往的使用多个子网堆叠的多尺度方法，文中使用单个网络就能提取多尺度特征，从而降低了训练难度。为了评估网络的去模糊效果和泛化性能，提出的算法在基准数据集GoPro、HIDE和真实数据集RealBlur上均进行了测试。在GoPro和HIDE数据集上的峰值信噪比值分别为31.73 dB和29.39 dB，结构相似度值分别为0.951和0.923，其结果均高于目前先进的去模糊算法，并且在真实数据集RealBlur上也取得了最佳效果。实验结果表明，提出的去模糊算法相比现有算法去模糊更为彻底，能有效地复原图像的边缘轮廓和纹理细节信息，并且能够提升后续高级计算机视觉任务的鲁棒性。

针对现有的放射性物质探测手段有效距离近和效率较低等局限性，考虑到高功率微波（HPM）良好的空间辐射特性，研究放射性物质对微波大气击穿特性的影响，以实现利用HPM远距离探测放射性物质的设想。阐释了微波脉冲等离子体击穿原理和自由电子对击穿特性影响，分析了放射性物质¹³⁷Cs射线产生自由电子的过程，在此基础上分析了HPM大气击穿时间和击穿阈值。基于HPM大气击穿等离子体实验装置，分别在6000 Pa、7000 Pa和8000 Pa的低气压环境对有、无放射源存在情形开展多次HPM辐照实验。实验结果表明：放射源的存在降低了约10%的HPM大气击穿阈值，缩短约50%的击穿时间。