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融入注意力机制的小样本遥感图像场景分类 被引量:2
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作者 张多纳 赵宏佳 +2 位作者 鲁远耀 崔健 张宝昌 《计算机工程与应用》 CSCD 北大核心 2024年第4期173-182,共10页
遥感图像场景分类是计算机视觉领域的热点研究方向,对遥感图像场景及其语义理解意义重大。目前,基于深度学习的遥感图像场景分类方法在该领域占据主导地位。然而实际应用场景面临着样本数据较少、模型泛化能力较差的问题,致使基于深度... 遥感图像场景分类是计算机视觉领域的热点研究方向,对遥感图像场景及其语义理解意义重大。目前,基于深度学习的遥感图像场景分类方法在该领域占据主导地位。然而实际应用场景面临着样本数据较少、模型泛化能力较差的问题,致使基于深度学习的遥感图像场景分类方法实现难度较大,性能大幅下降。针对上述难点,提出了基于注意力机制的小样本遥感图像场景分类方法,设计了一种双分支判别结构进行相似性度量。该方法基于元学习训练策略对数据集进行任务制划分;为最大限度保留遥感图像中的特征分布,对输入图像进行重叠分块;在特征提取网络中引入轻量级注意力模块,降低过拟合风险并保证判别性特征的获取;在EMD(earth mover’s distance)距离的基础上设计添加双分支相似性度量模块,提升分类器的判别能力。实验结果表明,相较于经典小样本学习方法,所提出的小样本遥感图像场景分类方法能够显著提升分类性能。 展开更多
关键词 遥感图像场景分类 小样本学习 元学习 注意力机制 分支判别
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T型线路的行波精确故障测距新方法 被引量:24
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作者 张峰 梁军 +2 位作者 杜涛 张利 贠志皓 《高电压技术》 EI CAS CSCD 北大核心 2009年第3期527-532,共6页
在行波故障测距原理基础上,对T型线路的行波故障测距方法进行了研究,提出了综合利用T型线路的三端测量数据进行故障测距的思路,并依此提出了故障分支判别的新判据和故障点测距的新方法。分支判别判据考虑了实际测距误差因素对分支误判... 在行波故障测距原理基础上,对T型线路的行波故障测距方法进行了研究,提出了综合利用T型线路的三端测量数据进行故障测距的思路,并依此提出了故障分支判别的新判据和故障点测距的新方法。分支判别判据考虑了实际测距误差因素对分支误判情况的影响,确保分支判别的有效性;故障点的测距过程中充分利用T型线路的三端测量数据,提出了利用三端数据进行故障测距的新方法。同时,测距表达式中消去了波速不确定性对测距结果的影响,并且一定程度上消除了线路弧垂对测距结果带来的误差。ATP/EMTP仿真结果表明,所提方法可以对T型线路进行精确的故障分支判别和故障点的测距。 展开更多
关键词 行波 T型线路 三端数据 分支判别 故障测距 波速
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T接输电线路故障测距的新型算法 被引量:2
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作者 化雨 鲁改凤 王文涛 《水电能源科学》 北大核心 2010年第4期133-134,共2页
针对T接输电线路故障测距三端数据采样的非同步,采用均匀传输线方程理论对T接输电线路的故障进行了分析与计算,提出了利用非同步数据采样方法判别故障分支,进而对故障的分支测距实现对T接输电线路的故障测距。该方法精度高、便于计算机... 针对T接输电线路故障测距三端数据采样的非同步,采用均匀传输线方程理论对T接输电线路的故障进行了分析与计算,提出了利用非同步数据采样方法判别故障分支,进而对故障的分支测距实现对T接输电线路的故障测距。该方法精度高、便于计算机实现。 展开更多
关键词 T接输电线路 故障测距 均匀传输线 非同步测距 故障分支判别
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Predicting pillar stability for underground mine using Fisher discriminant analysis and SVM methods 被引量:16
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作者 周健 李夕兵 +2 位作者 史秀志 魏威 吴帮标 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2011年第12期2734-2743,共10页
The purpose of this study is to apply some statistical and soft computing methods such as Fisher discriminant analysis (FDA) and support vector machines (SVMs) methodology to the determination of pillar stability ... The purpose of this study is to apply some statistical and soft computing methods such as Fisher discriminant analysis (FDA) and support vector machines (SVMs) methodology to the determination of pillar stability for underground mines selected from various coal and stone mines by using some index and mechanical properties, including the width, the height, the ratio of the pillar width to its height, the uniaxial compressive strength of the rock and pillar stress. The study includes four main stages: sampling, testing, modeling and assessment of the model performances. During the modeling stage, two pillar stability prediction models were investigated with FDA and SVMs methodology based on the statistical learning theory. After using 40 sets of measured data in various mines in the world for training and testing, the model was applied to other 6 data for validating the trained proposed models. The prediction results of SVMs were compared with those of FDA as well as the measured field values. The general performance of models developed in this study is close; however, the SVMs exhibit the best performance considering the performance index with the correct classification rate Prs by re-substitution method and Pcv by cross validation method. The results show that the SVMs approach has the potential to be a reliable and practical tool for determination of pillar stability for underground mines. 展开更多
关键词 underground mine pillar stability Fisher discriminant analysis (FDA) support vector machines (SVMs) PREDICTION
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T接输电线路故障测距的行波算法 被引量:1
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作者 王文涛 林森 曹俊建 《电气自动化》 2011年第3期81-83,共3页
针对T接输电线路故障测距问题,将行波故障测距方法应用于T接输电线路故障。首先进行故障分支的判定,其次,把复杂的三端输电线路通过运算化简为比较简单的双端输电线路,然后利用双端行波故障测距的方法进行故障测距,得到故障的位置。同... 针对T接输电线路故障测距问题,将行波故障测距方法应用于T接输电线路故障。首先进行故障分支的判定,其次,把复杂的三端输电线路通过运算化简为比较简单的双端输电线路,然后利用双端行波故障测距的方法进行故障测距,得到故障的位置。同时在行波测距装置中增加行波波形记忆模块、使用较高的采样精度,确保双端行波测距的可行性。 展开更多
关键词 T接输电线路 故障分支判别 输电线路分布参数 三端线路的二端等效 双端行波故障测距
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复炼菜籽废油的紫外光谱辨识指标 被引量:3
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作者 余盖文 刘晔 +2 位作者 王明明 李云雁 刘大川 《食品科学》 EI CAS CSCD 北大核心 2019年第20期311-317,共7页
为确立餐饮废油的快速、可靠辨识指标,以菜籽油为样本考察加工、使用及复炼等多种热处理对油脂紫外光谱的影响.采用0.05 mm薄膜样品池采集油样紫外吸收光谱可获得特征参数D245 nm和R272 nm,分别用以表征油中二元及三元共轭结构产物的多... 为确立餐饮废油的快速、可靠辨识指标,以菜籽油为样本考察加工、使用及复炼等多种热处理对油脂紫外光谱的影响.采用0.05 mm薄膜样品池采集油样紫外吸收光谱可获得特征参数D245 nm和R272 nm,分别用以表征油中二元及三元共轭结构产物的多寡.结果表明,菜籽油经正常精炼热处理后,其紫外光谱特征参数D245 nm和R272 nm值分别不超过4.8和12.9.高温氧化可导致上述特征参数的大幅上升,而复炼处理也不能降低R272 nm值.由此利用特征参数D245 nm和R272 nm值边界值及分支判别流程可将正常加工的菜籽油与高温氧化油或复炼氧化油区分开来,对于复炼脱臭油掺杂的检出限为2.3%. 展开更多
关键词 复炼菜籽废油 紫外光谱 特征参数 辨识指标 分支判别
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DIMENSIONALITY REDUCTION BASED ON SVM AND LDA,AND ITS APPLICATION TO CLASSIFICATION TECHNIQUE 被引量:1
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作者 杨波 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2009年第4期306-312,共7页
Some dimensionality reduction (DR) approaches based on support vector machine (SVM) are proposed. But the acquirement of the projection matrix in these approaches only considers the between-class margin based on S... Some dimensionality reduction (DR) approaches based on support vector machine (SVM) are proposed. But the acquirement of the projection matrix in these approaches only considers the between-class margin based on SVM while ignoring the within-class information in data. This paper presents a new DR approach, call- ed the dimensionality reduction based on SVM and LDA (DRSL). DRSL considers the between-class margins from SVM and LDA, and the within-class compactness from LDA to obtain the projection matrix. As a result, DRSL can realize the combination of the between-class and within-class information and fit the between-class and within-class structures in data. Hence, the obtained projection matrix increases the generalization ability of subsequent classification techniques. Experiments applied to classification techniques show the effectiveness of the proposed method. 展开更多
关键词 classification information pattern recognition dimensionality reduction (DR) support vectormachine (SVM) linear discriminant analysis (LDA)
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Brain-Computer Interface Design Using Signal Powers Extracted During Motor Imagery Tasks
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作者 HE Ke-ren WANG Xin-guang +1 位作者 ZOU Ling MA Zheng-hua 《Chinese Journal of Biomedical Engineering(English Edition)》 2011年第4期139-149,共11页
Accurate classification of EEG left and right hand motor imagery is an important issue in brain-computer interface. Firstly, discrete wavelet transform method was used to decompose the average power of C3 electrode an... Accurate classification of EEG left and right hand motor imagery is an important issue in brain-computer interface. Firstly, discrete wavelet transform method was used to decompose the average power of C3 electrode and C4 electrode in left-right hands imagery movement during some periods of time. The reconstructed signal of approximation coefficient A6 on the 6al level was selected to build up a feature signal. Secondly, the performances by Fisher Linear Discriminant Analysis with two different threshold calculation ways and Support Vector Machine methods were compared. The final classification results showed that false classification rate by Support Vector Machine was lower and gained an ideal classification results. 展开更多
关键词 brain-computer interface motor imagery feature extraction pattern classification
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