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Feature Selection Based on Enhanced Cuckoo Search for Breast Cancer Classification in Mammogram Image
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作者 M. N. Sudha S. Selvarajan 《Circuits and Systems》 2016年第4期327-338,共12页
Proposed system has been developed to extract the optimal features from the breast tumors using Enhanced Cuckoo Search (ECS) and presented in this paper. The texture feature, intensity histogram feature, radial distan... Proposed system has been developed to extract the optimal features from the breast tumors using Enhanced Cuckoo Search (ECS) and presented in this paper. The texture feature, intensity histogram feature, radial distance feature and shape features have been extracted and the optimal feature set has been obtained using ECS. The overall accuracy of a minimum distance classifier and k-Nearest Neighbor (k-NN) on validation samples is used as a fitness value for ECS. The new approach is carried out on the extracted feature dataset. The proposed system selects only the minimum number of features and performed the accuracy of 98.75% with Minimum Distance Classifier and 99.13% with k-NN Classifier. The performance of the new ECS is compared with the Cuckoo Search and Harmony Search. This result shows that the ECS algorithm is more accurate than the other algorithm. The proposed system can provide valuable information to the physician in medical pathology. 展开更多
关键词 Breast Cancer Classification feature extraction enhanced Cuckoo Search
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Wake-Up-Word Feature Extraction on FPGA
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作者 Veton ZKepuska Mohamed MEljhani Brian HHight 《World Journal of Engineering and Technology》 2014年第1期1-12,共12页
Wake-Up-Word Speech Recognition task (WUW-SR) is a computationally very demand, particularly the stage of feature extraction which is decoded with corresponding Hidden Markov Models (HMMs) in the back-end stage of the... Wake-Up-Word Speech Recognition task (WUW-SR) is a computationally very demand, particularly the stage of feature extraction which is decoded with corresponding Hidden Markov Models (HMMs) in the back-end stage of the WUW-SR. The state of the art WUW-SR system is based on three different sets of features: Mel-Frequency Cepstral Coefficients (MFCC), Linear Predictive Coding Coefficients (LPC), and Enhanced Mel-Frequency Cepstral Coefficients (ENH_MFCC). In (front-end of Wake-Up-Word Speech Recognition System Design on FPGA) [1], we presented an experimental FPGA design and implementation of a novel architecture of a real-time spectrogram extraction processor that generates MFCC, LPC, and ENH_MFCC spectrograms simultaneously. In this paper, the details of converting the three sets of spectrograms 1) Mel-Frequency Cepstral Coefficients (MFCC), 2) Linear Predictive Coding Coefficients (LPC), and 3) Enhanced Mel-Frequency Cepstral Coefficients (ENH_MFCC) to their equivalent features are presented. In the WUW- SR system, the recognizer’s frontend is located at the terminal which is typically connected over a data network to remote back-end recognition (e.g., server). The WUW-SR is shown in Figure 1. The three sets of speech features are extracted at the front-end. These extracted features are then compressed and transmitted to the server via a dedicated channel, where subsequently they are decoded. 展开更多
关键词 Speech Recognition System feature extraction Mel-Frequency Cepstral Coefficients Linear Predictive Coding Coefficients enhanced Mel-Frequency Cepstral Coefficients Hidden Markov Models Field-Programmable Gate Arrays
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Automated Extraction for Water Bodies Using New Water Index from Landsat 8 OLI Images 被引量:3
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作者 Pu YAN Yue FANG +2 位作者 Jie CHEN Gang WANG Qingwei TANG 《Journal of Geodesy and Geoinformation Science》 CSCD 2023年第1期59-75,共17页
The extraction of water bodies is essential for monitoring water resources,ecosystem services and the hydrological cycle,so analyzing water bodies from remote sensing images is necessary.The water index is designed to... The extraction of water bodies is essential for monitoring water resources,ecosystem services and the hydrological cycle,so analyzing water bodies from remote sensing images is necessary.The water index is designed to highlight water bodies in remote sensing images.We employ a new water index and digital image processing technology to extract water bodies automatically and accurately from Landsat 8 OLI images.Firstly,we preprocess Landsat 8 OLI images with radiometric calibration and atmospheric correction.Subsequently,we apply KT transformation,LBV transformation,AWEI nsh,and HIS transformation to the preprocessed image to calculate a new water index.Then,we perform linear feature enhancement and improve the local adaptive threshold segmentation method to extract small water bodies accurately.Meanwhile,we employ morphological enhancement and improve the local adaptive threshold segmentation method to extract large water bodies.Finally,we combine small and large water bodies to get complete water bodies.Compared with other traditional methods,our method has apparent advantages in water extraction,particularly in the extraction of small water bodies. 展开更多
关键词 water bodies extraction Landsat 8 OLI images water index improved local adaptive threshold segmentation linear feature enhancement
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Underwater Sea Cucumber Target Detection Based on Edge-Enhanced Scaling YOLOv4
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作者 Ziting Zhang Hang Zhang +3 位作者 Yue Wang Tonghai Liu Yuxiang He Yunchen Tian 《Journal of Beijing Institute of Technology》 EI CAS 2023年第3期328-340,共13页
Sea cucumber detection is widely recognized as the key to automatic culture.The underwater light environment is complex and easily obscured by mud,sand,reefs,and other underwater organisms.To date,research on sea cucu... Sea cucumber detection is widely recognized as the key to automatic culture.The underwater light environment is complex and easily obscured by mud,sand,reefs,and other underwater organisms.To date,research on sea cucumber detection has mostly concentrated on the distinction between prospective objects and the background.However,the key to proper distinction is the effective extraction of sea cucumber feature information.In this study,the edge-enhanced scaling You Only Look Once-v4(YOLOv4)(ESYv4)was proposed for sea cucumber detection.By emphasizing the target features in a way that reduced the impact of different hues and brightness values underwater on the misjudgment of sea cucumbers,a bidirectional cascade network(BDCN)was used to extract the overall edge greyscale image in the image and add up the original RGB image as the detected input.Meanwhile,the YOLOv4 model for backbone detection is scaled,and the number of parameters is reduced to 48%of the original number of parameters.Validation results of 783images indicated that the detection precision of positive sea cucumber samples reached 0.941.This improvement reflects that the algorithm is more effective to improve the edge feature information of the target.It thus contributes to the automatic multi-objective detection of underwater sea cucumbers. 展开更多
关键词 sea cucumber edge extraction feature enhancement edge-enhanced scaling You Only Look Once-v4(YOLOv4)(ESYv4) model scaling
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A Study on Enhancing Chip Detection Efficiency Using the Lightweight Van-YOLOv8 Network
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作者 Meng Huang Honglei Wei Xianyi Zhai 《Computers, Materials & Continua》 SCIE EI 2024年第4期531-547,共17页
In pursuit of cost-effective manufacturing,enterprises are increasingly adopting the practice of utilizing recycled semiconductor chips.To ensure consistent chip orientation during packaging,a circular marker on the f... In pursuit of cost-effective manufacturing,enterprises are increasingly adopting the practice of utilizing recycled semiconductor chips.To ensure consistent chip orientation during packaging,a circular marker on the front side is employed for pin alignment following successful functional testing.However,recycled chips often exhibit substantial surface wear,and the identification of the relatively small marker proves challenging.Moreover,the complexity of generic target detection algorithms hampers seamless deployment.Addressing these issues,this paper introduces a lightweight YOLOv8s-based network tailored for detecting markings on recycled chips,termed Van-YOLOv8.Initially,to alleviate the influence of diminutive,low-resolution markings on the precision of deep learning models,we utilize an upscaling approach for enhanced resolution.This technique relies on the Super-Resolution Generative Adversarial Network with Extended Training(SRGANext)network,facilitating the reconstruction of high-fidelity images that align with input specifications.Subsequently,we replace the original YOLOv8smodel’s backbone feature extraction network with the lightweight VanillaNetwork(VanillaNet),simplifying the branch structure to reduce network parameters.Finally,a Hybrid Attention Mechanism(HAM)is implemented to capture essential details from input images,improving feature representation while concurrently expediting model inference speed.Experimental results demonstrate that the Van-YOLOv8 network outperforms the original YOLOv8s on a recycled chip dataset in various aspects.Significantly,it demonstrates superiority in parameter count,computational intricacy,precision in identifying targets,and speed when compared to certain prevalent algorithms in the current landscape.The proposed approach proves promising for real-time detection of recycled chips in practical factory settings. 展开更多
关键词 Lightweight neural networks attention mechanisms image super-resolution enhancement feature extraction small object detection
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Underwater Image Enhancement Based on Multi-scale Adversarial Network
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作者 ZENG Jun-yang SI Zhan-jun 《印刷与数字媒体技术研究》 CAS 北大核心 2024年第5期70-77,共8页
In this study,an underwater image enhancement method based on multi-scale adversarial network was proposed to solve the problem of detail blur and color distortion in underwater images.Firstly,the local features of ea... In this study,an underwater image enhancement method based on multi-scale adversarial network was proposed to solve the problem of detail blur and color distortion in underwater images.Firstly,the local features of each layer were enhanced into the global features by the proposed residual dense block,which ensured that the generated images retain more details.Secondly,a multi-scale structure was adopted to extract multi-scale semantic features of the original images.Finally,the features obtained from the dual channels were fused by an adaptive fusion module to further optimize the features.The discriminant network adopted the structure of the Markov discriminator.In addition,by constructing mean square error,structural similarity,and perceived color loss function,the generated image is consistent with the reference image in structure,color,and content.The experimental results showed that the enhanced underwater image deblurring effect of the proposed algorithm was good and the problem of underwater image color bias was effectively improved.In both subjective and objective evaluation indexes,the experimental results of the proposed algorithm are better than those of the comparison algorithm. 展开更多
关键词 Underwater image enhancement Generative adversarial network Multi-scale feature extraction Residual dense block
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Enhanced Answer Selection in CQA Using Multi-Dimensional Features Combination 被引量:3
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作者 Hongjie Fan Zhiyi Ma +2 位作者 Hongqiang Li Dongsheng Wang Junfei Liu 《Tsinghua Science and Technology》 SCIE EI CAS CSCD 2019年第3期346-359,共14页
Community Question Answering(CQA) in web forums, as a classic forum for user communication,provides a large number of high-quality useful answers in comparison with traditional question answering.Development of method... Community Question Answering(CQA) in web forums, as a classic forum for user communication,provides a large number of high-quality useful answers in comparison with traditional question answering.Development of methods to get good, honest answers according to user questions is a challenging task in natural language processing. Many answers are not associated with the actual problem or shift the subjects,and this usually occurs in relatively long answers. In this paper, we enhance answer selection in CQA using multidimensional feature combination and similarity order. We make full use of the information in answers to questions to determine the similarity between questions and answers, and use the text-based description of the answer to determine whether it is a reasonable one. Our work includes two subtasks:(a) classifying answers as good, bad, or potentially associated with a question, and(b) answering YES/NO based on a list of all answers to a question. The experimental results show that our approach is significantly more efficient than the baseline model, and its overall ranking is relatively high in comparison with that of other models. 展开更多
关键词 COMMUNITY QUESTION answering information RETRIEVAL multi-dimensional features extraction SIMILARITY computation
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Diagnosis of Leukemia Disease Based on Enhanced Virtual Neural Network 被引量:1
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作者 K.Muthumayil S.Manikandan +3 位作者 S.Srinivasan JoséEscorcia-Gutierrez Margarita Gamarra Romany F.Mansour 《Computers, Materials & Continua》 SCIE EI 2021年第11期2031-2044,共14页
White Blood Cell(WBC)cancer or leukemia is one of the serious cancers that threaten the existence of human beings.In spite of its prevalence and serious consequences,it is mostly diagnosed through manual practices.The... White Blood Cell(WBC)cancer or leukemia is one of the serious cancers that threaten the existence of human beings.In spite of its prevalence and serious consequences,it is mostly diagnosed through manual practices.The risks of inappropriate,sub-standard and wrong or biased diagnosis are high in manual methods.So,there is a need exists for automatic diagnosis and classification method that can replace the manual process.Leukemia is mainly classified into acute and chronic types.The current research work proposed a computer-based application to classify the disease.In the feature extraction stage,we use excellent physical properties to improve the diagnostic system’s accuracy,based on Enhanced Color Co-Occurrence Matrix.The study is aimed at identification and classification of chronic lymphocytic leukemia using microscopic images of WBCs based on Enhanced Virtual Neural Network(EVNN)classification.The proposed method achieved optimum accuracy in detection and classification of leukemia from WBC images.Thus,the study results establish the superiority of the proposed method in automated diagnosis of leukemia.The values achieved by the proposed method in terms of sensitivity,specificity,accuracy,and error rate were 97.8%,89.9%,76.6%,and 2.2%,respectively.Furthermore,the system could predict the disease in prior through images,and the probabilities of disease detection are also highly optimistic. 展开更多
关键词 White blood cells enhanced virtual neural networking SEGMENTATION feature extraction chronic lymphocytic leukemia
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RF-Net: Unsupervised Low-Light Image Enhancement Based on Retinex and Exposure Fusion
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作者 Tian Ma Chenhui Fu +2 位作者 Jiayi Yang Jiehui Zhang Chuyang Shang 《Computers, Materials & Continua》 SCIE EI 2023年第10期1103-1122,共20页
Low-light image enhancement methods have limitations in addressing issues such as color distortion,lack of vibrancy,and uneven light distribution and often require paired training data.To address these issues,we propo... Low-light image enhancement methods have limitations in addressing issues such as color distortion,lack of vibrancy,and uneven light distribution and often require paired training data.To address these issues,we propose a two-stage unsupervised low-light image enhancement algorithm called Retinex and Exposure Fusion Network(RFNet),which can overcome the problems of over-enhancement of the high dynamic range and under-enhancement of the low dynamic range in existing enhancement algorithms.This algorithm can better manage the challenges brought about by complex environments in real-world scenarios by training with unpaired low-light images and regular-light images.In the first stage,we design a multi-scale feature extraction module based on Retinex theory,capable of extracting details and structural information at different scales to generate high-quality illumination and reflection images.In the second stage,an exposure image generator is designed through the camera response mechanism function to acquire exposure images containing more dark features,and the generated images are fused with the original input images to complete the low-light image enhancement.Experiments show the effectiveness and rationality of each module designed in this paper.And the method reconstructs the details of contrast and color distribution,outperforms the current state-of-the-art methods in both qualitative and quantitative metrics,and shows excellent performance in the real world. 展开更多
关键词 Low-light image enhancement multiscale feature extraction module exposure generator exposure fusion
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基于CycleGAN-IA方法和M-ConvNext网络的苹果叶片病害图像识别 被引量:1
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作者 李云红 张蕾涛 +3 位作者 李丽敏 苏雪平 谢蓉蓉 史含驰 《农业机械学报》 EI CAS CSCD 北大核心 2024年第4期204-212,共9页
针对苹果叶片病害图像识别存在数据集获取困难、样本不足、识别准确率低等问题,提出基于多尺度特征提取的病害识别网络(Multi-scale feature extraction ConvNext,M-ConvNext)模型。采用一种结合改进的循环一致性生成对抗网络与仿射变... 针对苹果叶片病害图像识别存在数据集获取困难、样本不足、识别准确率低等问题,提出基于多尺度特征提取的病害识别网络(Multi-scale feature extraction ConvNext,M-ConvNext)模型。采用一种结合改进的循环一致性生成对抗网络与仿射变换的数据增强方法(Improved CycleGAN and affine transformation,CycleGAN-IA),首先,使用较小感受野的卷积核和残差注意力模块优化CycleGAN网络结构,使用二值交叉熵损失函数代替CycleGAN网络的均方差损失函数,以此生成高质量样本图像,提高样本特征复杂度;然后,对生成图像进行仿射变换,提高数据样本的空间复杂度,该方法解决了数据样本不足的问题,用于辅助后续的病害识别模型。其次,构建M-ConvNext网络,该网络设计G-RFB模块获取并融合各个尺度的特征信息,GELU激活函数增强网络的特征表达能力,提高苹果叶片病害图像识别准确率。最后,实验结果表明,CycleGAN-IA数据增强方法可以对数据集起到良好的扩充作用,在常用网络上验证,增强后的数据集可以有效提高苹果叶片病害图像识别准确率;通过消融实验可得,M-ConvNex识别准确率可达99.18%,较原ConvNext网络准确率提高0.41个百分点,较ResNet50、MobileNetV3和EfficientNetV2网络分别提高3.78、7.35、4.07个百分点,为后续农作物病害识别提供了新思路。 展开更多
关键词 苹果叶片 病害识别 生成式对抗网络 数据增强 多尺度特征提取
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改进YOLOX的遥感图像目标检测算法 被引量:1
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作者 梁燕 饶星晨 《计算机工程与应用》 CSCD 北大核心 2024年第12期181-188,共8页
针对遥感图像目标检测算法复杂背景下目标检测精度低、小目标特征丢失的问题,提出一种改进YOLOX的遥感图像目标检测算法MYOLOX(modified YOLOX)。该算法在主干网络引入残差金字塔卷积模块(residual pyramid convolution module,RPCM)增... 针对遥感图像目标检测算法复杂背景下目标检测精度低、小目标特征丢失的问题,提出一种改进YOLOX的遥感图像目标检测算法MYOLOX(modified YOLOX)。该算法在主干网络引入残差金字塔卷积模块(residual pyramid convolution module,RPCM)增强浅层特征图中的空间位置等细节信息,缓解下采样过程中的特征丢失。引入增强跨阶段局部块(improved cross stage partial block,ICSP)提取丰富的上下文信息并抑制噪声干扰,减少复杂背景及噪声干扰带来误检。将改进算法应用于使用DIOR数据集对NWPU VHR-10数据集扩充后数据集和SSDD数据集,MYOLOX算法检测平均精度均值(mean average precision,mAP)分别达到了80.8%和94.4%,较原算法提升了4.1和4.5个百分点。实验结果证明,改进后的算法能够明显提高遥感图像目标检测精度。 展开更多
关键词 目标检测 遥感图像 多尺度特征提取 浅层特征增强
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基于多分支空谱特征增强的高光谱图像分类 被引量:1
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作者 李铁 李文许 +1 位作者 王军国 高乔裕 《液晶与显示》 CAS CSCD 北大核心 2024年第6期844-855,共12页
为了解决高光谱图像自身及分类过程中噪声干扰大、空间-光谱特征信息提取不足以及有限样本下分类性能不佳等问题,提出一种基于多分支空谱特征增强的高光谱图像分类模型SSFE-MBACNN。首先,利用多分支特征提取模块分别提取浅层空谱特征和... 为了解决高光谱图像自身及分类过程中噪声干扰大、空间-光谱特征信息提取不足以及有限样本下分类性能不佳等问题,提出一种基于多分支空谱特征增强的高光谱图像分类模型SSFE-MBACNN。首先,利用多分支特征提取模块分别提取浅层空谱特征和深层空间特征信息,并引入注意力机制抑制噪声干扰。其次,设计一种改进多尺度空谱特征提取融合模块及结合双池化和空洞卷积的空间特征增强模块实现空谱特征增强,减少模型参数量和提高分类性能。最后,用全局平均池化层代替全连接层,进一步降低参数量,缓解模型过拟合问题。实验结果表明,在Indian Pines(10%训练样本)、Pavia University (5%训练样本)和Salinas(1%训练样本)数据集分别取得了0.990 7、0.997 5和0.994 7的总体分类精度。SSFE-MBACNN不仅能充分利用空谱特征信息,而且在有限样本下也取得了优秀的分类性能,明显高于其他对比方法。 展开更多
关键词 高光谱图像分类 特征增强 多分支特征提取 注意力机制 多尺度特征 双池化 空洞卷积
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基于多尺度残差注意力网络的水下图像增强 被引量:1
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作者 陈清江 王炫钧 邵菲 《应用光学》 CAS 北大核心 2024年第1期89-98,共10页
针对水下图像由水的散射、吸收引起的色偏、色弱、信息丢失问题,提出了一种基于多尺度残差注意力网络的水下图像增强算法。该网络引入了改进的UNet3+-Avg结构与注意力机制,设计出多尺度密集特征提取模块与残差注意力恢复模块,以及由Char... 针对水下图像由水的散射、吸收引起的色偏、色弱、信息丢失问题,提出了一种基于多尺度残差注意力网络的水下图像增强算法。该网络引入了改进的UNet3+-Avg结构与注意力机制,设计出多尺度密集特征提取模块与残差注意力恢复模块,以及由Charbonnier损失和边缘损失相结合的联合损失函数,使该网络得以学习到多个尺度的丰富特征,在改善图像色彩的同时又可保留大量的物体边缘信息。增强后图像的平均峰值信噪比(PSNR)达到23.63 dB、结构相似度(SSIM)达到0.93。与其他水下图像增强网络的对比实验结果表明,由该网络所增强的图像在主观感受与客观评价上都取得了显著的效果。 展开更多
关键词 图像处理 水下图像增强 多尺度特征提取 密集连接 注意力机制
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基于激光雷达回波信号的雾天船舶航线快速辨识
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作者 杨喜旺 黄晋英 《舰船科学技术》 北大核心 2024年第6期135-139,共5页
激光雷达所处环境噪声较大,船舶航线辨识困难,为解决该问题,提出基于激光雷达回波信号的雾天船舶航线快速辨识方法。采用信号累积增强算法增强雾天激光雷达回波信号,利用改进经验模态分解算法去噪处理增强后的回波信号,结合回波信号通... 激光雷达所处环境噪声较大,船舶航线辨识困难,为解决该问题,提出基于激光雷达回波信号的雾天船舶航线快速辨识方法。采用信号累积增强算法增强雾天激光雷达回波信号,利用改进经验模态分解算法去噪处理增强后的回波信号,结合回波信号通过最小类内方差获取得到船舶航线和水面最佳分割阈值,提取船舶航线特征点。利用最小二乘法拟合法拟合船舶航线特征点,完成雾天船舶航线辨识。实验结果表明,所提方法应用后激光雷达回波信号更平滑,输出信噪比更高,均方根误差更低,船舶航线辨识准确率更理想。 展开更多
关键词 激光雷达回波信号 船舶航线辨识 回波信号累积增强 经验模态分解 特征提取
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语义增强与高阶强交互的SAR图像舰船检测
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作者 郭伟 杨涵西 +1 位作者 李煜 王春艳 《遥感信息》 CSCD 北大核心 2024年第3期32-39,共8页
合成孔径雷达(synthetic aperture radar,SAR)图像背景信息复杂、舰船目标边缘模糊,且多为容易丢失的小尺度舰船目标。针对上述问题,提出语义增强与高阶强交互的SAR图像舰船检测。该方法利用部分卷积与非对称卷积构建部分非对称卷积聚... 合成孔径雷达(synthetic aperture radar,SAR)图像背景信息复杂、舰船目标边缘模糊,且多为容易丢失的小尺度舰船目标。针对上述问题,提出语义增强与高阶强交互的SAR图像舰船检测。该方法利用部分卷积与非对称卷积构建部分非对称卷积聚合网络,在减少计算复杂度、轻量化主干网络的同时,更好地捕捉多尺度舰船特征,同时在上采样部分引入双层路由注意力,增强对图像上下文信息的利用。另外,通过递归的方式进行特征提取,可以较好解决区域内信息交互的问题,实现不同级别特征之间的高阶交互建模,提升模型检测能力。在公开的HRSID遥感数据集上进行实验的结果表明,该方法的检测精度达到91.23%,相比原模型提升5.13%,准确率与召回率分别提升2.41%和7.16%,与主流算法相比具有较好的检测效果。 展开更多
关键词 合成孔径雷达 目标检测 语义增强 高阶强交互 特征提取
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复杂光线环境下星载激光光斑图像特征参数提取
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作者 王腾 李凯勇 《激光杂志》 CAS 北大核心 2024年第9期141-145,共5页
星载激光光斑图像易受采集时复杂光线背景的影响,导致激光光斑特征参数提取精度不佳,由此提出复杂光线环境下星载激光光斑图像特征参数提取方法。首先,基于光照校正的Retinex图像增强算法光照补偿及增强星载激光光斑图像,以消除复杂光... 星载激光光斑图像易受采集时复杂光线背景的影响,导致激光光斑特征参数提取精度不佳,由此提出复杂光线环境下星载激光光斑图像特征参数提取方法。首先,基于光照校正的Retinex图像增强算法光照补偿及增强星载激光光斑图像,以消除复杂光线环境的影响;其次,基于二次阈值分割与形态学消噪结合方法提取光斑边界;最后,使用一阶灰度重心法与椭圆拟合结合方法完成激光光斑图像特征参数提取。仿真结果表明,所提方法的星载激光光斑图像特征参数提取精度保持在95%以上,具有较好的提取性能。 展开更多
关键词 光照校正 星载激光光斑图像 Retinex图像增强算法 二次阈值分割 特征参数提取
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EHDE和WHO-SVM模型在齿轮箱故障诊断中的应用
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作者 马晓娜 周海超 《机电工程》 CAS 北大核心 2024年第4期622-632,共11页
针对现有齿轮箱故障诊断方法对数据长度敏感的缺陷,提出了一种基于增强层次多样性熵(EHDE)和野马算法(WHO)优化支持向量机(SVM)的齿轮箱故障诊断模型。首先,传统熵值特征提取方法在特征提取阶段对数据样本的长度比较敏感,为此提出了增... 针对现有齿轮箱故障诊断方法对数据长度敏感的缺陷,提出了一种基于增强层次多样性熵(EHDE)和野马算法(WHO)优化支持向量机(SVM)的齿轮箱故障诊断模型。首先,传统熵值特征提取方法在特征提取阶段对数据样本的长度比较敏感,为此提出了增强层次多样性熵,并将其作为特征提取指标用于提取齿轮箱的故障特征;其次,采用WHO算法对SVM模型的参数进行了优化,建立了参数最优的WHO-SVM分类器;最后,将故障特征样本输入至WHO-SVM分类器中进行了训练和识别,完成了样本的故障识别;利用齿轮箱数据集分别从数据长度敏感性、算法特征提取时间、模型诊断性能三种角度对EHDE、精细复合多尺度样本熵、精细复合多尺度模糊熵、精细复合多尺度排列熵、精细复合多尺度散布熵、精细复合多尺度波动散布熵进行了对比研究。研究结果表明:EHDE方法对数据长度的要求较低,在数据长度为512时即可以取得99.1%的平均识别准确率,在诊断稳定性和诊断精度方面均优于其他对比方法;在算法的泛化性实验中,EHDE方法能够以98%的准确率识别齿轮箱的不同故障类型,具有明显的泛化性和通用性。 展开更多
关键词 齿轮箱故障诊断 增强层次多样性熵 野马算法优化支持向量机 数据长度敏感性 算法特征提取时间 模型诊断性能
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基于增强特征提取的森林遥感图像行人小目标检测网络 被引量:1
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作者 李春燕 王超 +2 位作者 金星 符利勇 业巧林 《林业工程学报》 CSCD 北大核心 2024年第4期130-139,共10页
林业作业人员常常由于复杂地貌而面对坠落、森林火灾等威胁,卷积神经网络结合无人机巡查的方法已经成为主流防范、搜救措施,但遥感图片中的行人小目标有特征少、定位精度要求高以及极易受背景信息干扰的特点。为了能够使森林遥感图片行... 林业作业人员常常由于复杂地貌而面对坠落、森林火灾等威胁,卷积神经网络结合无人机巡查的方法已经成为主流防范、搜救措施,但遥感图片中的行人小目标有特征少、定位精度要求高以及极易受背景信息干扰的特点。为了能够使森林遥感图片行人小目标检测的精度达到预期,在YOLOv4方法的基础上针对上述特点设计了增强特征提取的目标检测网络(EFEN),通过构建感受野增强模块(RFBA)并结合CBAM注意力机制,在充分利用遥感图片中的丰富上下文信息之余,对相关信息进行动态选择,增强特征的表示能力;基于高斯分布思想,将归一化Wasserstein距离与CIOU结合,提出了一种新的损失函数(GKCLOSS),降低了小目标检测任务中对位置偏差的敏感性;引入一种自适应分割训练检测策略,平衡正负样本,提高目标检测的准确性,进一步提高了检测精度。以河北省张家口市崇礼区采集的无人机行人图像为研究对象,实验表明,EFEN框架在小目标检测方面优于现有的深度学习网络,在与SSD、YOLOv5、YOLOv7等算法比较中平均查准率(mAP)均有所提升,在上述数据集上,mAP高达39.10%,证明了此方法对行人小目标数据的有效性。 展开更多
关键词 遥感图像 行人小目标 增强特征提取 感受野增强模块 GKCLOSS损失函数
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基于加强特征提取的道路病害检测算法
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作者 龙伍丹 彭博 +2 位作者 胡节 申颖 丁丹妮 《计算机应用》 CSCD 北大核心 2024年第7期2264-2270,共7页
针对道路病害区域小、类别数量不均衡导致检测困难的问题,提出基于YOLOv7-tiny的道路病害检测算法RDD-YOLO。首先,采用K-means++算法得到拟合目标尺寸更好的锚框。其次,在小目标检测支路上使用量化感知重参数化模块(QARepVGG),增强浅层... 针对道路病害区域小、类别数量不均衡导致检测困难的问题,提出基于YOLOv7-tiny的道路病害检测算法RDD-YOLO。首先,采用K-means++算法得到拟合目标尺寸更好的锚框。其次,在小目标检测支路上使用量化感知重参数化模块(QARepVGG),增强浅层特征提取,同时构建加强注意力模块(AM-CBAM)嵌入颈部的3个输入,抑制复杂背景干扰。然后,设计特征融合模块(Res-RFB),模拟人眼扩大感受野融合多尺度信息,提高表征能力;另外,构造轻量级解耦头(S-DeHead)提高小目标检测精确率。最后,采用归一化Wasserstein距离度量(NWD)优化小目标定位过程,并缓解样本不均衡问题。实验结果表明,与YOLOv7-tiny相比,RDD-YOLO算法在仅增加0.71×10^(6)参数量和1.7 GFLOPs计算量的成本下,mAP50提高6.19个百分点,F1-Score提高5.31个百分点,并且检测速度达到135.26 frame/s,满足道路养护工作中对检测精度和速度的需求。 展开更多
关键词 道路病害检测 加强特征提取 YOLOv7-tiny 小目标 类别数量不平衡
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基于改进TextSnake的印章字符检测算法
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作者 甘辉鑫 巩荣芬 +1 位作者 储茂祥 杨永辉 《辽宁科技大学学报》 CAS 2024年第3期213-220,共8页
针对字符模糊、宽高比多变、与背景文字重叠等因素导致的印章字符易被漏检、误检等问题,提出基于TextSnake的印章字符检测算法,记作TextSnake-CR算法。首先在特征融合中嵌入手工设计的感受野增强模块,使浅层特征拥有更大感受视野,从而... 针对字符模糊、宽高比多变、与背景文字重叠等因素导致的印章字符易被漏检、误检等问题,提出基于TextSnake的印章字符检测算法,记作TextSnake-CR算法。首先在特征融合中嵌入手工设计的感受野增强模块,使浅层特征拥有更大感受视野,从而有效地降低误检率;其次提出颜色特征提取模块,用于提取印章字符中颜色特征,增强模糊印章字符的检测精度;最后改进模型的分类损失函数,抑制背景噪声对模型的干扰,进一步提高模型检测性能。实验结果表明,TextSnake-CR在公开印章数据集与自制数据集上的F值分别达到90.71%和81.79%,与其他算法相比,有效地提高了印章字符检测准确率。 展开更多
关键词 印章字符检测 TextSnake 颜色特征提取 感受野增强 分类损失函数
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