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关键词： Alpha particles   Trajectory   Particle ions   CMOS camera   EM-CCD camera   AUTORADIOGRAPHY   WATER   IRRADIATION   PERFORMANCE  

摘要： High-resolution and real-time imaging of particle ion trajectories is essential in nuclear medicine and nuclear engineering. One potential method to achieve high-resolution real-time trajectory imaging of particle ions involves utilizing an imaging system that integrates a scintillator plate with a magnifying unit and a cooled electron multiplying charge-coupled device (EM-CCD) camera. However, acquiring an EM-CCD camera might prove challenging due to the discontinuation of CCD sensor manufacturing by vendors. As an alternative imaging approach, a low-noise, high-sensitivity camera utilizing a cooled complementary metal-oxide-semiconductor (CMOS) sensor offers a promising solution for imaging particle ion trajectories. Yet, it remains uncertain whether CMOS-based cameras can perform as effectively as CCD-based cameras in capturing particle ion trajectories. To address these concerns, we conducted a comparative analysis of the imaging performance between a CMOS-based system and an EM-CCD-based system for capturing alpha particle trajectories. The results revealed that both systems could image the trajectories of alpha particle, but the spatial resolution with the CMOS-based camera exceeded that of the EM-CCD-based camera, primarily due to the smaller pixel size of the sensor. While the signal-to-noise ratio (SNR) of the trajectory image from the CMOS-based camera initially lagged behind that from the EM-CCD-based camera, this disparity was mitigated by implementing binning techniques on the CMOSbased camera images. In conclusion, our findings suggest that a cooled CMOS camera could serve as a viable alternative for imaging particle ion trajectories.

关键词： Palm tree waste   Ocimum basilicum   Cellulose/silver nanocomposite   Bacteria removal   CCD   CELLULOSE   NANOPARTICLES  

摘要： This study used palm tree waste as a raw material for cellulose extraction. In addition, basil leaf extract (Ocimum basilicum) was used as a reducing agent in the preparation of AgNPs. Synthesized AgNPs were characterized by X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR). According to the characterization results, the generated AgNPs are of sufficient quality to prevent the growth of bacteria in wastewater. Subsequently, treated nanocrystals of palm cellulose (T) were synthesized. These quality AgNPs were used for the modification of TNPC to synthesize modified nanocomposite of palm tree cellulose (M), because AgNPs have a very high ability to denature bacteria. FTIR, XRD, and scanning electron microscopy (SEM) were applied to characterize these T and M. The M size distribution was determined using dynamic light scattering (DLS). Furthermore, raw palm tree cellulose (R) was characterized by FTIR, XRD, and SEM. The characterization results show that these materials exhibit distinct and related properties. The Ms were used to remove bacteria from spring water. Design Expert version 11 was used to design the experiments. The central composite design approach (CCD) derived from RSM was used to design the three crucial factors (dose, pH, and contact time) with three levels. The bacteria elimination experiments were carried out at batch mode conditions. Additionally, the optimization of process variables was performed. The determined ideal values for dosage, pH, and contact time were 7.6wt%, 6.8, and 31.6 min, respectively. The software predicted a 99.63% elimination percentage of bacteria, but the experimental result showed a 99.33% elimination rate. The difference between the experimental and predicted results was extremely tiny. Overall, the synthesized and modified cellulose/silver nanocomposite was very effective in eliminating microorganisms.

关键词： 猪舍环境湿度   无线传感器网络   多速率测量   数据融合  

摘要： 在智能化养殖背景下，针对猪舍环境数据融合精度不高的问题，提出了一种基于无线传感器网络的新型数据融合算法。首先对猪舍环境数据进行卡尔曼滤波估计，然后将估计值和测量值发送到头节点进行一致性分析和加权数据融合，最后将头节点的集群数据融合值发送给汇聚节点，并基于一致性分析，在汇聚节点上对不同头节点的集群数据融合值进行加权数据融合。通过实例试验验证，该算法能在保证猪舍环境湿度测量精度的前提下，利用自适应多速率测量模式减少无线湿度传感器的数据传输量和能量消耗。

关键词： PWM   红外检测   超声波   LED   蜂鸣器  

摘要： 为满足日常生活、学习中的需求,进行了关于多功能台灯的市场调查,发现了市场多功能台灯功能不足等现状.在对市场多功能台灯调查的基础上,针对台灯的智能性进行创新研究,运用超声波、PWM脉冲宽度调制、红外感应和光检测,设计出智能人体感应多功能台灯.台灯包含:人体感应模块、距离检测模块、时钟模块、报警模块、休息提醒模块等.实现对台灯亮度,工作时间的实时控制,还具有人体感应和距离检测用以保证用户用眼健康,以及对资源的节约.

关键词： 光通信   光纤准直器   霍夫圆检测   五轴调节平台   真空吸嘴   光耦合  

摘要： 为了解决波分复用器生产过程中光纤准直器耦合装配耗时长、自动化程度低等问题，设计了基于霍夫圆检测的五轴光纤准直器自动耦合装置。利用具有X、Y、Z三个移动自由度和R、J两个转动自由度的五轴调节平台带动U型真空吸嘴实现准直器稳定吸取和位姿调整。采用半透式红外光卡和相机模组构成视觉系统，利用霍夫圆检测获取光卡上光斑的中心坐标，通过五轴调节平台将准直器移动至与光斑中心相同的轴线上实现准直器位姿粗调。采用光功率计测量耦合光功率，R、J自由度微调准直器获取最佳耦合位姿，实现准直器精准耦合。样机试验表明：自动耦合装置效率比人工提高6倍，光纤准直器耦合效率高于75%，满足产品质量要求。该研究为光纤准直器高效自动耦合提供了参考。

关键词： 激光器   非线性光学   自相似脉冲   增益饱和能量  

摘要： 为了提高自相似子激光器可容忍的最高增益饱和能量，基于脉冲在色散渐减光纤（DDF）中进行自相似演化时具有较强抗光波分裂特性的原理，采用了DDF替代自相似子激光器中的单模光纤（SMF）的方法，进行了理论分析和仿真验证，取得了激光器可容忍的最高增益饱和能量增大33.3%、激光器的输出脉冲能量提高109.2%、脉冲峰值功率提高20.6%、脉宽缩短23.1%、自相似评价因子从0.077降低到0.065的效果。结果表明，在自相似子激光器中利用DDF替代SMF进行脉冲演化可有效提高激光器的最大增益饱和能量，进而使激光器的输出自相似脉冲的脉冲能量更大、脉冲峰值功率更高、脉宽更窄、脉冲质量更高。

关键词： Particle Nature of Dark Matter   Models for Dark Matter   TEMPERATURE-DEPENDENCE   CARRIER MOBILITY   MODEL   RECOMBINATION  

摘要： The reach of sub-GeV dark-matter detectors is at present severely affected by low-energy events from various origins. We present the theoretical methods to compute the single- and few-electron events that arise from secondary radiation emitted by high-energy particles as they pass through detector materials and perform a detailed simulation to quantify them at (Skipper) CCD-based experiments, focusing on the SENSEI data collected at Fermilab near the MINOS cavern. The simulations account for the generation of secondaries from Cherenkov and luminescent recombination radiation; photo-absorption in the bulk, backside layer, pitch adapter, and epoxy; the photon reflection and refraction at interfaces; thin-film interference; the roughness of the interfaces; the dynamics of charges produced in the highly doped CCD-backside-layers; and the partial charge collection on the CCD backside. We consider several systematic uncertainties, notably those stemming from the backside modeling, which we estimate with a "fiducial" and an "extreme" charge-diffusion model, with the former model being preferred due to better agreement with partial-charge collection data. We find that Cherenkov photons constitute about 30% of the observed single-electron events for both diffusion models; radiative recombination contributes negligibly to the event rate for the fiducial model, although it can dominate over Cherenkov for the extreme model. We also estimate the fraction of 2-electron events that arise from 1-electron event coincidences in the same pixel, finding that the entire 2-electron rate can be explained by coincidences of radiative events and spurious charge. Accounting for both radiative and non-radiative backgrounds, we project the sensitivity of future Skipper-CCD-based experiments to different dark-matter models. For light-mediator models with dark-matter masses of 1, 5, and 10 MeV, we find that future experiments with 10-kg-year exposures and successful background mitigation could h

摘要： 申请号: 202211271139.0 [申请日]2022.10.18 [公开号]CN115355830A [公开日]2022.11.18 [分类号]G02B6/255;G01B11/02 [申请人]南京信息工程大学 [发明人]张皓景;毛雅亚;王图涛;刘博;郭林峰

关键词： 机器视觉   卷积自编码器   数字图像处理   陶瓷瓦   裂纹检测  

摘要： 陶瓦表面有裂纹等多种缺陷，缺陷样本也十分稀缺，目前相关的检测方法多为传统数字图像处理技术，实际应用中参数调校繁琐、效率低。针对上述问题，将深度学习中的卷积自编码器应用于陶瓷瓦表面裂纹检测。首先进行预处理，取陶瓷瓦图像的红色通道图像并增强其对比度，再适当裁剪以分块；然后，使用卷积自编码器提取完整陶瓷瓦图像的特征，再重构裂纹陶瓷瓦图像，并将重构图像与原图像进行差分；最后，采用二值化和形态学方法检测裂纹。实验结果表明，上述方法能根据少量易获得的正常样本检测陶瓷瓦裂纹，检测准确率较高、速度较快，检测效果较好。