Infrared Physics & Technology最新文献_第8页

Investigation of vessel infrared radiation characteristics based on propulsion‑system heat source estimation 基于推进系统热源估算的船舶红外辐射特性研究

IF 3.4 3区物理与天体物理 Q2 INSTRUMENTS & INSTRUMENTATION

Infrared Physics & Technology

Pub Date : 2025-12-10 DOI: 10.1016/j.infrared.2025.106301

Yuchen Tang, Qunqing Lin, Dequan Fan, Dengfeng Ren, Yuge Han

This study addresses the critical challenge of accurately characterizing the infrared radiation signatures of marine vessels by coupling internal propulsion-system heat source predictions with external environmental factors. Using a comprehensive thermodynamic model developed in MATLAB/Simulink, we predict the influence of variable specific heat and oil–gas ratios on the vessel’s power system. These predictions are incorporated into a coupled heat transfer model that accounts for solar, sky, and sea radiation, as well as interactions with hull water and plume wake. The temperature distribution on the vessel’s surface, particularly on the chimney and radar, is identified as the primary factor influencing infrared emissions. Under sailing conditions, these surfaces reach temperatures up to 464 K, significantly higher than other vessel areas (around 300 K), and dominate the overall infrared signature. High-fidelity simulations, validated through iso-scale CUBI experiments with an average error of 1 K, show that the exhaust plume exhibits a peak radiance of 6.85 W/(m²·sr) in the 3–5 μm band, while the vessel’s signature peaks at 40.3 W/(m²·sr) in the 8–12 μm band. Analysis of the temperature and flow fields reveals a clear progression from internal heat generation to the resulting infrared radiation of the external surface and wake. For instance, the interior wall of the flue reaches 440 K, markedly higher than the exterior wall (340 K), underscoring the dominant effects of exhaust temperature and flow rate on the infrared signature. These results indicate that effective infrared suppression strategies should prioritize insulation and flow control in exhaust systems. The integrated modeling approach achieves a simulated temperature of 1042.05 K for power system components, deviating by only 0.7 % from the surveyed value of 1049.4 K. This work offers practical insights for naval stealth design and the deployment of infrared sensors in maritime environments.

该研究通过将内部推进系统热源预测与外部环境因素相结合，解决了准确表征船舶红外辐射特征的关键挑战。利用MATLAB/Simulink开发的综合热力学模型，预测了变比热和油气比对船舶动力系统的影响。这些预测被纳入一个耦合传热模型，该模型考虑了太阳、天空和海洋辐射，以及与船体水和羽流的相互作用。船舶表面，特别是烟囱和雷达表面的温度分布是影响红外发射的主要因素。在航行条件下，这些表面的温度高达464 K，明显高于其他船只区域（约300 K），并主导了整体红外特征。通过等尺度CUBI实验验证的高保真度模拟结果表明，排气羽流在3 ~ 5 μm波段的峰值辐射强度为6.85 W/(m2·sr)，而在8 ~ 12 μm波段的峰值辐射强度为40.3 W/（m2·sr）。对温度场和流场的分析揭示了从内部产生热量到外部表面和尾迹产生红外辐射的明显进展。例如，烟道内壁达到440 K，明显高于外墙（340 K），强调排气温度和流量对红外特征的主要影响。这些结果表明，有效的红外抑制策略应该优先考虑排气系统的隔热和流量控制。综合建模方法实现了电力系统部件的模拟温度为1042.05 K，与调查值1049.4 K仅相差0.7%。这项工作为海军隐身设计和在海洋环境中部署红外传感器提供了实用的见解。

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引用次数: 0

Geographical origin traceability of Phyllanthi Fructus based on a spectral fusion strategy of near- and mid-infrared data 基于近红外和中红外光谱融合策略的番荔枝产地溯源研究

IF 3.4 3区物理与天体物理 Q2 INSTRUMENTS & INSTRUMENTATION

Infrared Physics & Technology

Pub Date : 2025-12-10 DOI: 10.1016/j.infrared.2025.106314

Shamukaer Alimujiang , Yao Zhang , Changhao Jia , Baozhong Duan , Wenlong Li

Phyllanthi Fructus is widely utilized in the food and functional ingredient industries due to its abundant bioactive compounds and notable nutritional benefits. However, its quality varies considerably depending on the environmental conditions of the cultivation region, necessitating the development of efficient, non-destructive methods for authentication and quality assessment. This study integrates near-infrared (NIR) and mid-infrared (MIR) spectroscopy with data fusion strategies to establish a rapid origin discrimination and quality evaluation model for Phyllanthi Fructus. By comparing low-level data fusion (LLDF), mid-level data fusion (MLDF), and high-level data fusion (HLDF) data fusion strategies, the results demonstrate that the MLDF strategy, when combined with a random forest (RF) classifier, achieves optimal classification performance, attaining a test set classification accuracy of 98.00%. This study provides a reliable technical solution for non-destructive, rapid traceability and quality control, and offers valuable insights for the development of standardized quality evaluation methods for functional food ingredients derived from natural products.

余兰果因其丰富的生物活性成分和显著的营养价值而被广泛应用于食品和功能配料行业。然而，其质量因种植地区的环境条件而有很大差异，因此需要开发有效、非破坏性的鉴定和质量评估方法。本研究将近红外（NIR）和中红外（MIR）光谱技术与数据融合技术相结合，建立了番荔枝的快速产地鉴别和质量评价模型。通过对低级数据融合（LLDF）、中级数据融合（MLDF）和高级数据融合（HLDF）数据融合策略的比较，结果表明，当与随机森林（RF）分类器结合使用时，MLDF策略的分类性能最优，测试集分类准确率达到98.00%。本研究为无损、快速追溯和质量控制提供了可靠的技术解决方案，为开发标准化的天然产品功能性食品配料质量评价方法提供了有价值的见解。

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引用次数: 0

Influence of absorber/barrier strain on 1/f noise characteristic of very long wavelength infrared detectors with InAs/GaSb superlattice 吸收/势垒应变对InAs/GaSb超晶格超长波长红外探测器1/f噪声特性的影响

IF 3.4 3区物理与天体物理 Q2 INSTRUMENTS & INSTRUMENTATION

Infrared Physics & Technology

Pub Date : 2025-12-09 DOI: 10.1016/j.infrared.2025.106311

Hyun Woo Jang , Ko-Ku Kang , Jun Ho Eom , Seong Min Ryu , Ahreum Jang , Jong Gi Kim , Geon Woo Ryu , Junhyeok Yun , Seungbum Yu , Hyun Jin Lee , Han Jung , Sang Soon Yong , Young Ho Kim

Reducing 1/f noise is critical for enhancing VLWIR detector performance. However, its origin in T2SL nBn detectors remains unclear. In this study, we demonstrate that lattice mismatch at the absorber/barrier interface significantly contributes to 1/f noise. Structural and electrical analyses of three InAs/GaSb T2SL detectors reveal that increased absorber/barrier strain correlates directly with higher trap-assisted tunneling (TAT) current and greater 1/f noise. Our findings indicate a proportional relationship between interface strain, trap density, and 1/f noise magnitude, suggesting strain engineering as a promising strategy to suppress 1/f noise in VLWIR nBn detectors.

降低1/f噪声是提高VLWIR探测器性能的关键。然而，它在T2SL nBn探测器中的来源仍不清楚。在这项研究中，我们证明了吸收器/屏障界面的晶格失配显著地导致了1/f噪声。对三种InAs/GaSb T2SL探测器的结构和电学分析表明，吸收层/势垒应变的增加与更高的陷阱辅助隧道（TAT）电流和更高的1/f噪声直接相关。我们的研究结果表明，界面应变，陷阱密度和1/f噪声大小之间存在正比关系，这表明应变工程是抑制VLWIR nBn探测器中1/f噪声的有前途的策略。

引用次数: 0

Research on methods to enhance heterodyne photons utilization efficiency in coherent detection based on GM-APD 基于GM-APD的相干探测中提高外差光子利用效率的方法研究

IF 3.4 3区物理与天体物理 Q2 INSTRUMENTS & INSTRUMENTATION

Infrared Physics & Technology

Pub Date : 2025-12-08 DOI: 10.1016/j.infrared.2025.106310

Xiaojing Shi , Yanwen Sun , Kemin Liu , Lianliang Chen , Yaxing Chen , Yun Suo , Yu Bi , Jianfeng Sun

The GM-APD photon coherent detection system is capable of extracting information such as echo distance, intensity, and phase from the frequency domain, achieving a sensitivity at the single-photon level, which makes it suitable for detecting weak signals. In this system, the heterodyne photons utilization efficiency significantly impacts the signal-to-noise ratio (SNR). Therefore, methods to enhance the heterodyne photons utilization efficiency are proposed. Firstly, a clustering method is employed to ensure that each pixel of the detector corresponds closely to an optimal value of local oscillator (LO) light intensity, this approach addresses the issue of low heterodyne photon utilization caused by uneven light spots. Secondly, the work proposes LO modulation as a solution to mitigate peak noise generated by the LO that reduces heterodyne photon utilization. Finally, an experimental setup based on GM-APD photon coherent detection is established, comparative experiments are conducted to validate the effectiveness of these two proposed methods. Through all-fiber experiments, it was verified that the application of clustering methods improved the average single-pixel SNR by 1.7 times compared to the pre-clustering scenario. Building upon this clustering approach, modulation of the LO further enhanced the system’s mean SNR by an additional 93 %.

GM-APD光子相干探测系统能够从频域提取回波距离、强度、相位等信息，灵敏度达到单光子水平，适用于微弱信号的探测。在该系统中，外差光子利用效率对信噪比有显著影响。因此，提出了提高外差光子利用效率的方法。首先，采用聚类方法确保探测器的每个像素点与本振（LO）光强的最优值紧密对应，解决了光斑不均匀导致的外差光子利用率低的问题；其次，本工作提出了本端调制作为一种解决方案，以减轻本端产生的峰值噪声，从而降低外差光子的利用率。最后，建立了基于GM-APD光子相干探测的实验装置，并进行了对比实验，验证了两种方法的有效性。通过全光纤实验，验证了聚类方法的应用比聚类前提高了平均单像素信噪比1.7倍。在这种聚类方法的基础上，LO的调制进一步将系统的平均信噪比提高了93%。

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引用次数: 0

OPSL-pumped 47-fs Kerr-lens mode-locked Yb:GdScO3 laser opsl泵浦47-fs kerr透镜锁模Yb:GdScO3激光器

IF 3.4 3区物理与天体物理 Q2 INSTRUMENTS & INSTRUMENTATION

Infrared Physics & Technology

Pub Date : 2025-12-06 DOI: 10.1016/j.infrared.2025.106308

Yalong Liu , Peng Yu , Yinjie Zhuo , Shengjie Yu , Jianfa Chen , Dong Wang , Bin Xu , Cunzhu Tong , Xiaodong Xu , Jun Xu

High brightness pump sources are crucial for Kerr-lens mode-locked (KLM) femtosecond laser operation. In the current work, we use an optically pumped semiconductor disk laser (OPSL) to play a role as pump source of a KLM Yb:GdScO₃ laser and we achieve a stable ultrashort pulse laser output of 47 fs at about 1068 nm. The KLM laser has an average laser output power of 56 mW and a repetition rate of 93.7 MHz. To our knowledge, this is currently the shortest pulse duration of Yb-doped mode-locked laser pumped by OPSL. Moreover, OPSL has the potential for high power output, which is expected to bring new development for the research of KLM femtosecond lasers.

高亮度泵浦源是克尔透镜锁模（KLM）飞秒激光工作的关键。在本工作中，我们利用光泵浦半导体圆盘激光器（OPSL）作为KLM Yb:GdScO3激光器的泵浦源，在约1068 nm处实现了输出47 fs的稳定超短脉冲激光。KLM激光器的平均激光输出功率为56 mW，重复频率为93.7 MHz。据我们所知，这是目前OPSL抽运的最短的掺镱锁模激光器脉冲持续时间。此外，OPSL具有高功率输出的潜力，有望为KLM飞秒激光器的研究带来新的发展。

引用次数: 0

FSA-FCA: Fourier semantic augmentation with attention for enhanced vehicle temperature monitoring in roadside thermal imaging FSA-FCA：傅里叶语义增强与路边热成像中车辆温度监测的关注

IF 3.4 3区物理与天体物理 Q2 INSTRUMENTS & INSTRUMENTATION

Infrared Physics & Technology

Pub Date : 2025-12-06 DOI: 10.1016/j.infrared.2025.106305

Kunlin Han , Baoping Tang , Dayang Liu

Tunnel fires caused by vehicle spontaneous combustion pose significant hazards, making it crucial to detect and provide early warnings for vehicle fire risks in a timely manner. To address this, this study develops a real-time vehicle temperature monitoring and early warning system based on roadside thermal imaging and object detection, with a focus on detecting vehicles and their key regions. To tackle the performance degradation issues caused by low resolution and indistinct features in roadside thermal imaging images, a Fourier semantic augmentation (FSA) and a Fourier channel attention (FCA) are proposed and integrated into the YOLOv8 detection model. We evaluate the proposed method on the Tunnel-Vehicle Infrared (TV-IR) dataset, which comprises real-world collected data. The results indicate that, compared to the baseline model, the use of the FSA module would achieve improvements in recall, F1 score, and mAP50 by 6.5%, 2.5%, and 5.9%, respectively. The use of the FCA module could brought enhancements in recall, F1 score and mAP50 by 4.8%, 1.4%, and 3.5%, respectively. When both modules are used together, further improvements in recall, F1 score, and mAP50 would be observed, reaching 8.2%, 4.3%, and 7.4%, respectively, significantly surpassing the performance of models such as YOLOv5, YOLOv10, and YOLOv11.

车辆自燃引发的隧道火灾危害巨大，及时发现和预警车辆火灾风险至关重要。为此，本研究开发了一种基于路边热成像和目标检测的车辆温度实时监测预警系统，重点对车辆及其关键区域进行检测。为了解决路边热成像图像低分辨率和特征不清晰导致的性能下降问题，提出了傅里叶语义增强（FSA）和傅里叶通道注意（FCA）方法，并将其集成到YOLOv8检测模型中。我们在隧道-车辆红外（TV-IR）数据集上对该方法进行了评估，该数据集包含真实世界的收集数据。结果表明，与基线模型相比，使用FSA模块将使召回率、F1分数和mAP50分别提高6.5%、2.5%和5.9%。使用FCA模块可以使召回率、F1分数和mAP50分别提高4.8%、1.4%和3.5%。当这两个模块一起使用时，召回率、F1分数和mAP50将进一步提高，分别达到8.2%、4.3%和7.4%，显著超过YOLOv5、YOLOv10和YOLOv11等模型的性能。

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引用次数: 0

Non-destructive thickness testing of TBCs using synthetic aperture imaging with pulsed terahertz waves 脉冲太赫兹波合成孔径成像对tbc厚度的无损检测

IF 3.4 3区物理与天体物理 Q2 INSTRUMENTS & INSTRUMENTATION

Infrared Physics & Technology

Pub Date : 2025-12-06 DOI: 10.1016/j.infrared.2025.106306

Yuhao Pan , Yuanhao Du , Deyue An , Hui Feng , Shuai Wu

Non-destructive thickness testing of thermal barrier coatings on turbine blades is crucial for ensuring their thermal insulation performance. The complex structure of thermal barrier coatings presents a significant challenge to the precise measurement of the topcoat thickness. Currently, there is no effective method for non-destructive testing of thermal barrier coatings with complex structures. In this study, we propose a non-destructive thickness testing algorithm based on pulsed terahertz wave synthetic aperture imaging, which enables imaging of the entire surface and thickness measurement at each point. The proposed algorithm is applicable to surfaces of various shapes. Moreover, we propose a new method that simultaneously measures both the coating thickness and the refractive index from the terahertz 3D reconstructed image. Additionally, we employ an AI agent to determine the trustworthy region for thickness measurement. In this study, we perform precise thickness measurements on simulated thermal barrier coating samples, fabricated thermal barrier coating samples, and turbine blade thermal barrier coatings. The proposed algorithm enables thickness measurements of complex structures with an accuracy of 20 µm, offering a novel terahertz non-destructive testing method with broad potential for practical applications.

涡轮叶片热障涂层的无损厚度检测是保证叶片隔热性能的关键。热障涂层结构复杂，对面涂层厚度的精确测量提出了重大挑战。目前，对于结构复杂的热障涂层，还没有有效的无损检测方法。在本研究中，我们提出了一种基于脉冲太赫兹波合成孔径成像的无损测厚算法，实现了对整个表面的成像和每个点的厚度测量。该算法适用于各种形状的曲面。此外，我们还提出了一种从太赫兹三维重建图像中同时测量涂层厚度和折射率的新方法。此外，我们使用人工智能代理来确定厚度测量的可信区域。在这项研究中，我们对模拟热障涂层样品、制造热障涂层样品和涡轮叶片热障涂层进行了精确的厚度测量。提出的算法能够以20 μ m的精度测量复杂结构的厚度，提供了一种具有广泛实际应用潜力的新型太赫兹无损检测方法。

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引用次数: 0

Controllable generation of polarized solitons in an automated mode-locked fiber laser 自动锁模光纤激光器中偏振孤子的可控产生

IF 3.4 3区物理与天体物理 Q2 INSTRUMENTS & INSTRUMENTATION

Infrared Physics & Technology

Pub Date : 2025-12-05 DOI: 10.1016/j.infrared.2025.106302

Bingna Lu , Jingxuan Sun , Weichen Zhang , Yiqing Shu , Jianqing Li , Zian Cheak Tiu , Weicheng Chen

The generation of on-demand pulses in mode-locked fiber lasers remains a technical challenge. Current research on on-demand pulse generation focuses primarily on intensity-dependent scalar construction methods. These methods inherently yield arbitrary members of a general solution set characterized by identical spectral or temporal information, leading to inadequate evaluation of mode-locked pulses. To address this difficulty, we propose an automatic mode-locking technique to generate controllable polarized solitons in a fiber laser, advancing the understanding of on-demand pulse eigenstate generation. Using the constraints of identical spectra and autocorrelation traces (ACTs), we employ a customized loss function to intelligently evaluate soliton properties from a fiber laser. This approach maps the mode-locking region on the Poincaré sphere at a fixed pump power by first performing a coarse polarization scanning to determine the region range and then a refined one to record pulse states. Within the mode-locking region, we further create controllable polarized soliton states with either fixed ellipticity or fixed azimuth, whose states of polarization (SOPs) are characterized either by varying along parallels at fixed ellipticity or by rotating along meridians at fixed azimuth on the Poincaré sphere. Theoretical analysis further confirms the experimentally obtained phenomena that both ellipticity- and azimuth-locked polarized solitons with identical spectrotemporal information exhibit phase-driven evolution of their SOPs. Our work provides an automatic mode-locking approach for the controllable generation of polarized solitons by combining intensity-dependent information constraints with polarization manipulation, enabling accurate generation of pulse eigenstates and precise manipulation of pulse dynamics.

在锁模光纤激光器中产生按需脉冲仍然是一个技术挑战。目前对按需脉冲产生的研究主要集中在强度相关的标量构造方法上。这些方法固有地产生具有相同光谱或时间信息特征的通解集的任意成员，导致对锁模脉冲的评估不足。为了解决这一困难，我们提出了一种自动锁模技术，在光纤激光器中产生可控的偏振孤子，促进了对按需脉冲特征态产生的理解。利用相同光谱和自相关迹线的约束，我们采用自定义的损失函数来智能地评估光纤激光器的孤子特性。该方法首先进行粗偏振扫描以确定区域范围，然后进行精细偏振扫描以记录脉冲状态，从而在固定的泵浦功率下绘制出poincar球上的锁模区域。锁模区域内,我们进一步创建可控偏振孤子州与固定椭圆率或固定的方位,其偏振状态(安抚)具有通过不同固定椭圆率沿平行或旋转沿着经脉在庞加莱球固定方位。理论分析进一步证实了具有相同光谱时间信息的椭圆锁定偏振孤子和方位角锁定偏振孤子均表现出相位驱动的sop演化现象。我们的工作为极化孤子的可控生成提供了一种自动锁模方法，通过将强度相关信息约束与极化操作相结合，实现了脉冲特征态的精确生成和脉冲动力学的精确控制。

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引用次数: 0

Characterization of surface microcracks on aluminum alloy stiffened curved structures via joint scanning laser thermography 用关节扫描激光热成像技术表征铝合金加劲弯曲结构表面微裂纹

IF 3.4 3区物理与天体物理 Q2 INSTRUMENTS & INSTRUMENTATION

Infrared Physics & Technology

Pub Date : 2025-12-05 DOI: 10.1016/j.infrared.2025.106304

Huipeng Wang , Weisheng Li , Guoqing Zhang , Lihong Dong , Huizhong Liu

Aluminum alloy stiffened curved structures are critical load-bearing components in spacecraft, which are susceptible to developing microcracks under complex alternating stresses during service. These microcracks can lead to material failure and structural damage. Therefore, the early non-destructive detection and characterization of surface microcracks on such complex curved structures are of great importance for the service safety of the spacecrafts. This research addresses the technical challenge of surface microcrack detection on complex configurations by developing a joint scanning laser thermography (JSLT) system. The influence of scanning paths on detection effectiveness was analyzed, and the thermal response characteristics of parallel cracks located at the stiffener roots were investigated. To mitigate the high-gradient noise and specular reflection interference introduced by complex curved structures, a dynamic feature extraction-based thermal image reconstruction method with reflective background suppression was proposed, and a wavelet detrending method was employed to eliminate high temperature of excitation range, and multi-operator feature fusion method was employed for microcrack feature extraction. This method effectively improves the signal-to-noise ratio (SNR) and enhances the thermal response features of microcracks, enabling the detection of 6 μm open cracks parallel to the stiffener root on the uncoated aluminum alloy surfaces with complex configurations.

铝合金加筋弯曲结构是航天器的关键承载部件，在复杂交变应力作用下容易产生微裂纹。这些微裂纹会导致材料失效和结构损坏。因此，对这类复杂曲面结构表面微裂纹进行早期无损检测和表征，对航天器的使用安全具有重要意义。本研究通过开发一种联合扫描激光热成像（JSLT）系统，解决了复杂结构表面微裂纹检测的技术难题。分析了扫描路径对检测效果的影响，研究了加劲肋根部平行裂纹的热响应特性。为了减轻复杂弯曲结构带来的高梯度噪声和镜面反射干扰，提出了一种基于反射背景抑制的动态特征提取热图像重建方法，采用小波去趋势法消除激发范围高温，采用多算子特征融合法提取微裂纹特征。该方法有效地提高了微裂纹的信噪比，增强了微裂纹的热响应特征，能够在复杂结构的未涂层铝合金表面检测到平行于加力根的6 μm开口裂纹。

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引用次数: 0

Improved IPI dim and small target detection based on multi-directional gradient regularization 基于多向梯度正则化的改进IPI弱小目标检测

IF 3.4 3区物理与天体物理 Q2 INSTRUMENTS & INSTRUMENTATION

Infrared Physics & Technology

Pub Date : 2025-12-05 DOI: 10.1016/j.infrared.2025.106297

Yizhi Deng, Xiangsuo Fan, Tingting Li, Qingxiao Ma

Aiming at the problems of low signal-to-noise ratio and difficult background interference suppression in infrared weak and small target detection under complex environments, this paper proposes an improved IPI weak and small target detection model based on multi-directional gradient regularization. This method first establishes a multi-directional gradient regularization factor between pixels in order to better characterize the low-rank characteristics of the background. On this basis, this paper uses the difference of the characteristic values of the structure tensor in different regions to establish a new corner strength function to suppress the strong edge contour and strong noise in the structure tensor. Finally, the improved IPI structure tensor model is established, and the alternating direction method of multipliers (ADMM) is used to solve the model to achieve weak and small target detection. In the experimental verification, six different scenes with complex backgrounds are selected for comparison with six mainstream weak and small target detection algorithms. The experimental data show that the proposed algorithm can effectively achieve the task of weak and small target detection under complex scenarios.

针对复杂环境下红外弱小目标检测信噪比低、背景干扰抑制困难的问题，提出了一种改进的基于多向梯度正则化的红外弱小目标检测模型。该方法首先在像素之间建立多向梯度正则化因子，以便更好地表征背景的低秩特征。在此基础上，利用结构张量在不同区域的特征值差异，建立新的角强度函数，抑制结构张量中的强边缘轮廓和强噪声。最后，建立了改进的IPI结构张量模型，并采用乘法器交替方向法（ADMM）对模型进行求解，实现了弱小目标的检测。在实验验证中，选取了6个背景复杂的不同场景，对比了6种主流的弱小目标检测算法。实验数据表明，该算法能够有效地完成复杂场景下弱小目标的检测任务。

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引用次数: 0