邵斌 1,2,3杨华 1,2,3朱斌 1,2,3,*陈熠 1,2,3邹融平 1,2,3
1 国防科技大学电子对抗学院,安徽 合肥 230037
2 脉冲功率激光技术国家重点实验室,安徽 合肥 230037
3 红外与低温等离子体安徽省重点实验室,安徽 合肥 230037
语义分割网络对图像进行像素级分类,相较于目标检测其对于目标的精准定位更有优势,因此在红外小目标检测中发挥着重要作用。针对红外小目标的特点,提出一种基于实时语义分割的红外小目标检测网络。该网络基于双分支特征提取结构,采用渐进式特征融合模块和改进的Dice损失函数,使红外小目标分割的速度与效果达到良好的平衡。实验结果表明,该算法在较小参数量和计算量的情况下相较于FCN、ICNet、BiSeNet V2、STDCNet、TopFormer等5种算法达到较高的精度,在实际采集的红外小目标数据集上,其推理帧率相较于传统的FCN提升44%,达到117 frame/s,且红外小目标的交并比相较于与其推理帧率相近的TopFormer提升49%,有利于语义分割在红外小目标检测的实际应用。
图像处理 红外小目标 实时语义分割 双分支特征提取 渐进式特征融合 激光与光电子学进展
2023, 60(14): 1410006
西安建筑科技大学信息与控制工程学院,陕西 西安 710055
Overview: In many scenes in real life, collecting high-quality images is one of the key factors to achieve high accuracy in object detection, image segmentation, automatic driving, medical surgery, and other works. However, images and videos collected by electronic devices are very vulnerable to various environmental factors, such as poor lighting, resulting in low image brightness, color distortion, more noise, effective details, and texture information loss, which brings many difficulties to subsequent tasks and works. The enhancement of low-illumination images generally restores image clarity by increasing brightness, removing noise, and restoring image color. In recent years, the depth neural network has had a strong nonlinear fitting ability, which has achieved good results in low illumination enhancement, image deblurring, and other fields. However, the existing low illumination image enhancement algorithms will lead to color imbalance when improving image brightness and contrast, and easily ignore the impact of some noises. Based on the above questions, this paper proposes an image enhancement method with parallel mixed attention step-by-step fusion. With the aid of the limited correlation between local features extracted by weighting different multi-scale branches, the local image details under multiple receptive fields can complement each other, and use parallel mixed attention to focus on color information and lighting features at the same time, which effectively improves the detail representation of the network and reduces noises. Finally, shallow feature information is fused in multiple stages. In order to alleviate the model confusion caused by the weakening of color information expression and single-stage feature superposition caused by the increase of network depth. The ablation experiment, module multi-stage experiment, and multiple evaluation indexes are compared with the existing advanced methods on four commonly used datasets, which fully proves that the method proposed in this paper is superior to the comparison methods on multiple evaluation parameters, and can effectively improve the overall brightness of the image, adjust the image color imbalance and remove noises. Combining the follow-up research task of the subject and analyzing the shortcomings of the network, a way to simplify the model and improve the operation speed will be the key direction of the follow-up research task.
图像增强 多尺度加权聚合 并行混合注意力 渐进融合 信息冗余 image enhancement multiscale weighted aggregation parallel hybrid attention progressive integration information redundancy
仇永佳 1,2,3程正东 1,2,3,*赵大鹏 1,2,3杨华 1,2,3[ ... ]章沁钰 1,2,3
1 国防科技大学电子对抗学院,安徽 合肥 230037
2 脉冲功率激光技术国家重点实验室,安徽 合肥 230037
3 红外与低温等离子体安徽省重点实验室,安徽 合肥 230037
针对假目标红外欺骗干扰效能缺乏规范评估体系的问题,利用视觉显著性模型计算同一背景下真目标和假目标的显著性对比度,从而定量评估假目标的红外欺骗干扰效能。量值越小,说明假目标的红外欺骗干扰效果越好。实验结果表明,该评估方法不仅能定量反映单一假目标的红外欺骗干扰效能,还能区分不同类型假目标的红外欺骗干扰效能,具有较强的普适性。
图像处理 红外欺骗干扰效能 定量评估 视觉显著性 假目标 激光与光电子学进展
2023, 60(12): 1210014
设计了基于SiO2薄膜间隔的金纳米锥与金薄膜耦合结构表面等离子体共振折射率传感器。使用时域有限差分法研究了复合结构中的表面等离子体共振模式,复合结构不仅能够激发局域表面等离子体共振,也可激发传播表面等离子体共振。入射电磁波的能量部分通过单个金纳米锥耦合到局域表面等离子体,部分通过金纳米锥阵列二维光栅耦合到传播表面等离子体。在待测物折射率1.30~1.40的范围内,对复合结构的反射光谱进行了模拟研究,发现共振波长与分析物折射率呈线性关系,且由于局域和传播表面等离子体的高效激发,反射光谱共振峰处的反射率几乎为零。此外,在最优的金纳米锥几何参数下,传播表面等离子体共振模式的半高全宽非常窄,灵敏度和品质因数分别达到770 nm/RIU和113 RIU?1,具有良好的折射率传感性能。所设计的复合结构作为表面等离子体共振传感器有望广泛应用于生物检测领域。
金纳米锥 金薄膜 表面等离子体 折射率传感 gold nano cone gold film surface plasmon refractive index sensing
为了研制一种高效防治水稻稻瘟病菌剂,本文以水稻稻瘟病病原菌高效拮抗内生菌株灰褐色链霉菌Ahn75为研究对象,分析了不同助剂,包括营养物质、润湿剂、分散剂、紫外保护剂和稳定剂等对孢子萌发和菌剂稳定性能的影响,并探讨了优良助剂协同生防菌株对水稻稻瘟病的防效。结果发现,叶面肥、酵母提取物、吐温80和糊精均能显著促进链霉菌Ahn75孢子的萌发,且糊精还可一定程度保护Ahn75孢子免受紫外线伤害,而稳定剂海藻酸钠对链霉菌Ahn75孢子萌发影响最小,且表现出比其他稳定剂更好的稳定性能。室外盆栽试验显示,各助剂与Ahn75孢子悬浮液复配均能显著降低水稻叶瘟的发病率和病情指数,其中混合助剂的协同防效最佳,叶瘟防效达38.06%。结合室内和室外试验结果,最终确定菌剂的最佳配方为: 孢子含量1×108 CFU/mL、营养物质酵母提取物的质量分数0.05%、润湿分散剂吐温80 0.05%、紫外保护剂糊精1.00%、稳定剂海藻酸钠0.15%。该研究为生防链霉菌Ahn75菌株的田间应用提供了重要的理论依据和支撑。
水稻稻瘟病 内生链霉菌 菌剂 助剂 生物防效 rice blast endophytic Streptomyces agent adjuvants biocontrol effect
Author Affiliations
Abstract
1 College of Computer Science and Electronic Engineering, Hunan University, Changsha 410082, China
2 School of Geosciences and Info-Physics, Central South University, Changsha 410083, China
We demonstrate manipulating the interactions of a second-order soliton with a weak probe pulse under the condition of group velocity match and group velocity mismatch (GVMM). During these interactions, the second-order soliton acting as an effective periodic refractive-index barrier leads to the polychromatic scattering of the probe pulse, which is represented as unequally spaced narrow-band sources with adjustable spectral width. In the case of GVMM, almost all the spectral components of the narrow-band sources meet the nonlinear frequency conversion relationship by using the wavenumber-matching relationship due to the robustness of the second-order soliton under moderate high-order-dispersion perturbations, so this case is more conducive to the study of the soliton wells. In addition, different transmission states of a soliton well are demonstrated under different probe pulse properties in the fiber-optical analog of the event horizon. When the power of the probe pulse is strong enough, a dispersive wave can be generated from the collision of two fundamental solitons split from the two second-order solitons. These interesting phenomena investigated in this work as a combination of white- and black-hole horizons can be considered as promising candidates for frequency conversion and broadband supercontinuum generation.
second-order soliton well probe wave optical event horizon Chinese Optics Letters
2022, 20(11): 111901
1 中国科学院 半导体研究所 半导体照明研发中心, 北京 100083
2 中国科学院大学 材料科学与光电技术学院, 北京 100049
传统的直接镀铜(DPC)陶瓷基板的焊盘上镀有Ni/Au金属覆盖层,它会强烈吸收紫外(UV)光。为了提高深紫外发光二极管(DUV LED)的光提取效率(LEE),设计并制备了镀Al的双层金属镀层DPC陶瓷基板。这种基板拥有一层完全覆盖基板焊盘的Ni/Au镀层为LED提供电互连,以及一层部分覆盖Ni/Au镀层的高反射Al镀层为UV光提供优异的反射。测量了分别由镀Al的DPC陶瓷基板和仅有一层Ni/Au镀层的传统DPC陶瓷基板所封装的DUV LED的光学、电学和热学性质,并建立了LED封装体的模型并进行了分析。结果表明,通过使用镀Al的DPC陶瓷基板,DUV LED的光输出功率(LOP)提高了19.2%,功率效率(WPE)和外量子效率(EQE)则分别提高为传统封装的1.20和1.19倍。此外,经过160 h的老化测试,使用镀Al的DPC陶瓷基板封装的LED表现出了更好的可靠性。这种镀Al的双层金属镀层DPC陶瓷基板为通过封装改善DUV LED的LEE提供了可行的方法。
DUV LED封装 DPC陶瓷基板 光学特性 热阻 DUV LED packaging DPC ceramic substrate optical property thermal resistance