A multivariate grey incidence model for different scale data based on spatial pyramid pooling

In order to solve the problem that existing multivariate grey incidence models cannot be applied to time series on different scales, a new model is proposed based on spatial pyramid pooling.Firstly, local features of multivariate time series on different scales are pooled and aggregated by spatial pyramid pooling to construct n levels feature pooling matrices on the same scale. Secondly,Deng's multivariate grey incidence model is introduced to measure the degree of incidence between feature pooling matrices at each level. Thirdly, grey incidence degrees at each level are integrated into a global incidence degree. Finally, the performance of the proposed model is verified on two data sets compared with a variety of algorithms. The results illustrate that the proposed model is more effective and efficient than other similarity measure algorithms.

Local-Tetra-Patterns for Face Recognition Encoded on Spatial Pyramid Matching

Face recognition is a big challenge in the research field with a lot of problems like misalignment,illumination changes,pose variations,occlusion,and expressions.Providing a single solution to solve all these problems at a time is a challenging task.We have put some effort to provide a solution to solving all these issues by introducing a face recognition model based on local tetra patterns and spatial pyramid matching.The technique is based on a procedure where the input image is passed through an algorithm that extracts local features by using spatial pyramid matching andmax-pooling.Finally,the input image is recognized using a robust kernel representation method using extracted features.The qualitative and quantitative analysis of the proposed method is carried on benchmark image datasets.Experimental results showed that the proposed method performs better in terms of standard performance evaluation parameters as compared to state-of-the-art methods on AR,ORL,LFW,and FERET face recognition datasets.

HSPOG:An Optimized Target Recognition Method Based on Histogram of Spatial Pyramid Oriented Gradients

The Histograms of Oriented Gradients(HOG)can produce good results in an image target recognition mission,but it requires the same size of the target images for classification of inputs.In response to this shortcoming,this paper performs spatial pyramid segmentation on target images of any size,gets the pixel size of each image block dynamically,and further calculates and normalizes the gradient of the oriented feature of each block region in each image layer.The new feature is called the Histogram of Spatial Pyramid Oriented Gradients(HSPOG).This approach can obtain stable vectors for images of any size,and increase the target detection rate in the image recognition process significantly.Finally,the article verifies the algorithm using VOC2012 image data and compares the effect of HOG.

Automatic Segmentation Method for Cone-Beam Computed Tomography Image of the Bone Graft Region within Maxillary Sinus Based on the Atrous Spatial Pyramid Convolution Network

Sinus floor elevation with a lateral window approach requires bone graft(BG)to ensure sufficient bone mass,and it is necessary to measure and analyse the BG region for follow-up of postoperative patients.However,the BG region from cone-beam computed tomography(CBCT)images is connected to the margin of the maxillary sinus,and its boundary is blurred.Common segmentation methods are usually performed manually by experienced doctors,and are complicated by challenges such as low efficiency and low precision.In this study,an auto-segmentation approach was applied to the BG region within the maxillary sinus based on an atrous spatial pyramid convolution(ASPC)network.The ASPC module was adopted using residual connections to compose multiple atrous convolutions,which could extract more features on multiple scales.Subsequently,a segmentation network of the BG region with multiple ASPC modules was established,which effectively improved the segmentation performance.Although the training data were insufficient,our networks still achieved good auto-segmentation results,with a dice coefficient(Dice)of 87.13%,an Intersection over Union(Iou)of 78.01%,and a sensitivity of 95.02%.Compared with other methods,our method achieved a better segmentation effect,and effectively reduced the misjudgement of segmentation.Our method can thus be used to implement automatic segmentation of the BG region and improve doctors’work efficiency,which is of great importance for developing preliminary studies on the measurement of postoperative BG within the maxillary sinus.

基于Oracle 10g Spatial的栅格数据存储、管理及关键技术

在Oracle 10g Spatial可以存储管理矢量数据的基础上,研究栅格图像的存储与管理,分析了栅格数据、元数据、波段、图层、坐标系、物理存储结构等几个相关概念,探讨了存储管理中分块、索引、影像金字塔、地理参照等关键技术,最后用实验证明,采用Oracle 10gSpatial选件可以进行栅格图像的有效存储与管理.并设计了空间数据表结构,将空间对象的栅格数据、矢量数据及属性数据存储到同一数据库,实现了空间数据的一体化管理.

基于Oracle 9i Spatial的海量空间影像数据管理

利用Oracle 9iSpatial组件提供的模型和功能 ,研究了海量空间影像数据的管理技术。实验表明 ,采用规则分块技术和构建影像金字塔可以实现对超大空间影像的有效管理 ,并为高性能并行数据服务提供了实现基础。

基于Oracle 10g Spatial的空间栅格数据的存储与管理

深入地研究和分析了Oracle 10g Spatial中新增的栅格数据的存储和管理机制,包括其采用的数据模型、元数据管理机制、栅格金字塔策略及物理存储结构等。在实验中给出了一个比较典型的对栅格数据进行存储和管理的操作示例。同时,指出了Oracle提供的栅格数据上载工具存在的局限性,并针对该局限性提出了一种简单有效的解决方案。

一种针对SAR图像的舰船目标检测算法

由于环境复杂、舰船目标散焦和尺度的多样性,基于SAR图像的舰船目标检测仍然存在一些问题。提出了一种针对SAR图像的舰船目标检测算法。首先,基于可变形卷积构建舰船目标特征细化模块,提高对大长宽比姿态的舰船目标的特征提取能力;其次,在主干网络末尾引入了舰船空间金字塔聚合结构,增强对舰船目标的全局特征提取能力;最后,设计了尺度扩展特征金字塔网络,增强舰船浅层和深层特征信息的交互,提高对多尺度舰船目标的检测能力。实验结果表明,所提算法在HRSID数据集上的mAP达到了93.72%,F1分数达到了89.70%,优于所有比较算法,具有良好的检测效果。

Intelligent identification of oceanic eddies in remote sensing data via Dual-Pyramid UNet

海洋涡旋是大洋中重要的组成部分,对海洋能量和物质的输送至关重要.海洋涡旋的检测和表征无论是对于海洋气象学,海洋声学还是海洋生物学等领域都具有重要的研究价值.本文基于UNet架构,并结合金字塔分割注意力(PSA)模块和空洞空间卷积池化金字塔(ASPP)构造了Dual-Pyramid UNet模型,以平面异常和海表面温度数据中进行海洋涡旋的识别.实验在北大西洋和南大西洋两个涡旋活跃区域进行并选用多个评价指标对识别结果进行评价以证明模型的优异性能.

融合注意力和扩张卷积的遥感影像道路信息提取方法

针对高分辨率遥感影像语义分割存在地物边缘分割不连续、道路及背景特征复杂多样导致道路提取分割精度不高的问题,提出了一种融合双通道注意力和扩张卷积的遥感影像道路信息提取语义分割网络(A 2DU-Net)。首先,在特征提取部分引入坐标注意力(coordinate attention,CA)模块,捕捉道路位置、方向和跨通道信息,精确定位道路信息。其次,针对网络对细节特征丢失的敏感问题,在编码器的末端利用不同扩张率的空洞卷积构建多尺度特征融合的空洞空间金字塔池化模块(multi-scale Atrous spatial pyramid pooling module,MASPPM)来获得更大的感受野,提高网络性能。最后,为了避免U-Net中纯跳跃连接在语义上不相似特征的融合,在编码器和解码器的跳跃连接之间增加了双通道注意力机制来实现门控筛选,抑制非目标区域的特征,提高网络的分割精度。实验在公共道路数据集Massachusetts上对网络模型进行测试,OA(准确率)、交并比(IoU)、平均交并比(mIoU)和F1等评价指标分别达到98.07%、64.39%、81.20%和88.67%。与主流方法U-Net和DDUNet进行比较,mIoU分别提升了3.07%、0.22%,IoU分别提升了1.98%、0.52%。实验结果表明,所提出的方法优于所有的比较方法,能够有效提高道路分割的精确度。

基于深度学习的铁路异物侵限快速检测方法

针对列车运行环境内因意外突发事件所造成的异物侵限而影响列车安全运行的问题,在被广泛应用于工业领域的YOLOv3目标检测模型的基础之上,提出一种融合轨道限界和侵限异物识别的快速检测方法。首先,以ResNet-18网络作为铁路限界检测的主干网络,利用辅助检测模块提升限界检测精度,达到特征提取速度快,语义信息丰富充足等目标。同时采用基于行锚框的分割算法检测轨道线坐标位置,结合标准轨距下的限界定义确定铁路异物入侵限界的范围,以减少侵限异物检测的区域。其次,设计基于Octave卷积的层内多尺度残差模块,将单通道卷积变为基于图像频率的双通道卷积,以降低卷积计算量,进一步提升异物侵限算法的检测速度。最后,引入空间金字塔模块和特征自适应融合模块,实现高、低级语义信息交换,从而增加网络对不同尺度目标的感知能力,并减少语义冲突问题。通过对比实验验证异物侵限检测算法的精度、速度和有效性。实验结果表明,所述方法能以172帧/s的速度对轨道位置和限界区域进行检测,精确度达98.12%。与其他算法相比,在大中小3种目标尺度上都超越了其他对比算法。所提出的融合轨道限界和侵限异物检测的方法,在保证精度的前提下,速度达到YOLOv3算法的2倍,能够满足列车对侵限异物的实时检测需求。

基于YOLOv8的气象设备识别监控算法

在人烟稀少的地区,气象设备的监测与检查面临设备安置位置偏僻、缺乏实时巡检等问题。为解决这一难题,基于在图像识别领域表现卓越的YOLOv8算法,提出了一种新的气象设备识别监控模型,通过将原有的高效的空间金字塔池化(spatial pyramid pooling-fast,SPPF)层替换为空间金字塔池化-全连接空间金字塔卷积(spatial pyramid pooling-fully connected spatial pyramid convolution,SPPFCSPC)层,成功降低了计算量,提升了气象设备检测的速度。为了进一步提升模型在复杂环境下的性能,提出了YOLOv8-SA模型,通过在主干网络(backbone)中加入多头自注意力机制,更精准地捕获图像中不同区域之间的关联性,有力地提高了模型的准确性。为了验证模型的有效性,创建了一个专门的气象设备数据集,并进行了对比实验。实验结果表明,本文提出的YOLOv8-SA模型在检测速度和准确性方面均取得了显著的提升,在自制的数据集中检测精度为98.6%,与传统的YOLOv8模型相比,检测精度提升了0.6%。该模型可有效解决人烟稀少地区气象设备的监测问题,为提升监测系统的实用性和效率提供新思路。

引入Transformer的道路小目标检测

针对道路场景中检测小目标时漏检率较高、检测精度低的问题,提出一种引入Transformer的道路小目标检测算法。在原YOLOv4算法基础上,对多尺度检测进行改进,把浅层特征信息充分利用起来;设计ICvT(improved convolutional vision transformer)模块捕获特征内部的相关性,获得上下文信息,提取更加全面丰富的特征;在网络特征融合部分嵌入改进后的空间金字塔池化模块,在保持较小计算量的同时增加特征图的感受野。实验结果表明,在KITTI数据集上,算法检测精度达到91.97%,与YOLOv4算法相比,mAP提高了2.53%,降低了小目标的漏检率。

基于可分离卷积与小波变换融合的道路裂缝检测

针对目前对细小裂缝检测能力不强、分割精度低等问题,提出了一种改进的U-Net模型来检测路面裂缝,提高检测能力和分割精度。中文设计了新的模块MSDWBlock(Multi-Scale Depthwise Separable Convolutional Block),应用在编码器和解码器部分,通过深度可分离卷积增强模型的能力,扩大模型感受野,在跳跃连接部分引入了C2G注意力机制模块,提升模型对裂缝特征的感知能力;并引入了ASPP(Atrous Spatial Pyramid Pooling)和DWT(Discrete Wavelet Transformation)。ASPP通过在多个尺度上进行操作,有助于捕捉到裂缝的特征,而DWT能够减少卷积池化过程中的裂缝空间信息损失,保留裂缝边缘信息。这种结构设计使得网络更专注于裂缝的特征,从而提升了裂缝检测的准确性。通过实验证明所提模型显示出优于U-Net,Segnet,U2net等先进模型的精确性。在CFD数据集上mIoU,F1分别达到78.51%,0.868。这些成果表明,所提方法能有效提升道路裂缝检测的性能。

融合位置注意力机制与轻量化STDC网络的非结构化场景语义分割

近年来,非结构化道路分割已成为计算机视觉领域的重要研究方向之一.现有的大多数方法适合结构化道路的分割并无法满足非结构化道路分割的准确性与实时性需求.为了解决上述问题,本文对STDC网络进行改进,引入残差连接来更好地融合多尺度语义信息,还提出一种嵌入位置注意力模块的空洞空间卷积池化金字塔(PAASPP)来增强网络对道路等特定区域的位置感知能力.本文在RUGD与RELLIS-3D两个数据集上进行实验,所提出方法的MIoU在两个数据集的测试集上分别达到了50.78%和49.96%.

An improved deep dilated convolutional neural network for seismic facies interpretation

With the successful application and breakthrough of deep learning technology in image segmentation,there has been continuous development in the field of seismic facies interpretation using convolutional neural networks.These intelligent and automated methods significantly reduce manual labor,particularly in the laborious task of manually labeling seismic facies.However,the extensive demand for training data imposes limitations on their wider application.To overcome this challenge,we adopt the UNet architecture as the foundational network structure for seismic facies classification,which has demonstrated effective segmentation results even with small-sample training data.Additionally,we integrate spatial pyramid pooling and dilated convolution modules into the network architecture to enhance the perception of spatial information across a broader range.The seismic facies classification test on the public data from the F3 block verifies the superior performance of our proposed improved network structure in delineating seismic facies boundaries.Comparative analysis against the traditional UNet model reveals that our method achieves more accurate predictive classification results,as evidenced by various evaluation metrics for image segmentation.Obviously,the classification accuracy reaches an impressive 96%.Furthermore,the results of seismic facies classification in the seismic slice dimension provide further confirmation of the superior performance of our proposed method,which accurately defines the range of different seismic facies.This approach holds significant potential for analyzing geological patterns and extracting valuable depositional information.

NFHP-RN:AMethod of Few-Shot Network Attack Detection Based on the Network Flow Holographic Picture-ResNet

Due to the rapid evolution of Advanced Persistent Threats(APTs)attacks,the emergence of new and rare attack samples,and even those never seen before,make it challenging for traditional rule-based detection methods to extract universal rules for effective detection.With the progress in techniques such as transfer learning and meta-learning,few-shot network attack detection has progressed.However,challenges in few-shot network attack detection arise from the inability of time sequence flow features to adapt to the fixed length input requirement of deep learning,difficulties in capturing rich information from original flow in the case of insufficient samples,and the challenge of high-level abstract representation.To address these challenges,a few-shot network attack detection based on NFHP(Network Flow Holographic Picture)-RN(ResNet)is proposed.Specifically,leveraging inherent properties of images such as translation invariance,rotation invariance,scale invariance,and illumination invariance,network attack traffic features and contextual relationships are intuitively represented in NFHP.In addition,an improved RN network model is employed for high-level abstract feature extraction,ensuring that the extracted high-level abstract features maintain the detailed characteristics of the original traffic behavior,regardless of changes in background traffic.Finally,a meta-learning model based on the self-attention mechanism is constructed,achieving the detection of novel APT few-shot network attacks through the empirical generalization of high-level abstract feature representations of known-class network attack behaviors.Experimental results demonstrate that the proposed method can learn high-level abstract features of network attacks across different traffic detail granularities.Comparedwith state-of-the-artmethods,it achieves favorable accuracy,precision,recall,and F1 scores for the identification of unknown-class network attacks through cross-validation onmultiple datasets.

基于改进YOLOv5s算法的禁捕期长江渔船识别及应用研究

长江实行十年禁渔是长江生态环境修复的关键环节,针对禁渔期间长江非法捕捞渔船目标小、背景复杂、流动大等问题,提出了一种基于改进YOLOv5s的目标检测算法。该算法优化多尺度自适应锚框模块,采用改进的K-means++聚类算法,重新匹配适合长江船舶尺寸的锚框;使用轻量高效的坐标注意力(coordinate attention,CA)机制,提升模型关注目标通道信息特征的能力;采用SPPCSPPC(spatial pyramid pooling and context-aware spatial pyramid pooling combination)对特征图进行池化,提高小目标检测能力;通过构建长江船舶数据集训练得到最优权值模型。结果显示,改进后的模型在准确率、召回率、mAP0.5、mAP0.5∶0.9和原模型相比分别提高了1.5%、3.0%、2.4%、7.7%,且训练过程损失收敛更快,收敛值更低,能够准确快速识别出长江上的渔船目标。研究结果可为长江十年禁渔提供技术支持。

Low-dose CT image denoising method based on generative adversarial network

In order to solve the problems of artifacts and noise in low-dose computed tomography(CT)images in clinical medical diagnosis,an improved image denoising algorithm under the architecture of generative adversarial network(GAN)was proposed.First,a noise model based on style GAN2 was constructed to estimate the real noise distribution,and the noise information similar to the real noise distribution was generated as the experimental noise data set.Then,a network model with encoder-decoder architecture as the core based on GAN idea was constructed,and the network model was trained with the generated noise data set until it reached the optimal value.Finally,the noise and artifacts in low-dose CT images could be removed by inputting low-dose CT images into the denoising network.The experimental results showed that the constructed network model based on GAN architecture improved the utilization rate of noise feature information and the stability of network training,removed image noise and artifacts,and reconstructed image with rich texture and realistic visual effect.

基于YOLOv8n的航拍图像小目标检测算法

针对航拍图像小目标检测中存在目标密集和相互遮挡问题,提出一种基于YOLOv8n的航拍图像小目标检测算法。在主干网络末段,置换C2f中Bottleneck为改进后的FasterNet,保持通道数并提升收敛速度;替换SPPF中CBS激活函数SiLU为ReLU使输入负值置零,在CBS后引入SE注意力机制扩张感受野,保留更多小目标特征。输出端检测头前嵌入高效多尺度注意力机制EMA获取更多细节信息,进一步提高小目标关注度。将基线网络损失函数CIoU替换成Wise IoU,提供增益分配策略,专注普通质量锚框,提高网络泛化能力。在数据集VisDrone2021和RSOD上做消融实验和对比实验,相较于基线算法,mAP@0.5分别提升5.1和7.2个百分点,mAP@0.5:0.95分别提升4.4和2.1个百分点,表明检测精度指标显著提升;在公开数据集VOC2007+2012上做泛化实验,mAP@0.5提升3.8个百分点,表明具有良好的鲁棒性。