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A Filter-Based Pattern Search Method for Unconstrained Optimization 被引量:4
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作者 Ting Wu Linping Sun 《Numerical Mathematics A Journal of Chinese Universities(English Series)》 SCIE 2006年第3期209-216,共8页
We discuss a filter-based pattern search method for unconstrained optimization in this paper. For the purpose to broaden the search range we use both filter technique and frames, which are fragments of grids, to provi... We discuss a filter-based pattern search method for unconstrained optimization in this paper. For the purpose to broaden the search range we use both filter technique and frames, which are fragments of grids, to provide a new criterion of iterate acceptance. The convergence can be ensured under some conditions. The numerical result shows that this method is practical and efficient. 展开更多
关键词 直接搜索 模型搜索 滤波器 无约束优化
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A Novel Tracking-by-Detection Method with Local Binary Pattern and Kalman Filter 被引量:1
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作者 Zhongli Wang Chunxiao Jia +6 位作者 Baigen Cai Litong Fan Chuanqi Tao Zhiyi Zhang Yinling Wang Min Zhang Guoyan Lyu 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2018年第3期74-87,共14页
Tracking-Learning-Detection( TLD) is an adaptive tracking algorithm,which tracks by learning the appearance of the object as the video progresses and shows a good performance in long-term tracking task.But our experim... Tracking-Learning-Detection( TLD) is an adaptive tracking algorithm,which tracks by learning the appearance of the object as the video progresses and shows a good performance in long-term tracking task.But our experiments show that under some scenarios,such as non-uniform illumination changing,serious occlusion,or motion-blurred,it may fails to track the object. In this paper,to surmount some of these shortages,especially for the non-uniform illumination changing,and give full play to the performance of the tracking-learning-detection framework, we integrate the local binary pattern( LBP) with the cascade classifiers,and define a new classifier named ULBP( Uniform Local Binary Pattern) classifiers. When the object appearance has rich texture features,the ULBP classifier will work instead of the nearest neighbor classifier in TLD algorithm,and a recognition module is designed to choose the suitable classifier between the original nearest neighbor( NN) classifier and the ULBP classifier. To further decrease the computing load of the proposed tracking approach,Kalman filter is applied to predict the searching range of the tracking object.A comprehensive study has been conducted to confirm the effectiveness of the proposed algorithm (TLD _ULBP),and different multi-property datasets were used. The quantitative evaluations show a significant improvement over the original TLD,especially in various lighting case. 展开更多
关键词 Tracking-Learning-Detection (TLD) local binary pattern (LBP) Kalman filter
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A STATISTICAL NOISE MODEL AND MATHEMATICAL MODEL OF SPECKLE PATTERN AND ADAPTIVE FILTERING APPROACH
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作者 杨亦兵 何振亚 《Journal of Electronics(China)》 1995年第1期24-32,共9页
A statistical noise model and a mathematical model for real speckle pattern are presented in this paper, and then, in view of the models, a new adaptive suboptimal image filtering approach is proposed. The proposed ap... A statistical noise model and a mathematical model for real speckle pattern are presented in this paper, and then, in view of the models, a new adaptive suboptimal image filtering approach is proposed. The proposed approach, with the local direction features of speckle pattern, combines the characteristics of optimal linear filter with non-linear filter and is an adaptive approximation to linear minimum mean square error filter. Experimental results show that the proposed approach has fairly good edge-preserved performance, compared with other present image filters, as well as much better filtering performance and robustness for speckle pattern. 展开更多
关键词 SPECKLE pattern NOISES Adaptive filterING
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基于情境感知和序列模式挖掘的气象学习资源推荐算法 被引量:2
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作者 王帅 马景奕 +1 位作者 周远洋 王甫棣 《气象科技》 2024年第1期37-44,共8页
随着互联网的快速发展,气象部门职工作为学习者可以获得的学习资源得到极大丰富。信息超载导致检索合适的在线学习资源时遇到了困难;学习者在不同学习环境和序列访问模式上也有不同的学习需求。但是,现有的推荐系统,如基于内容的推荐和... 随着互联网的快速发展,气象部门职工作为学习者可以获得的学习资源得到极大丰富。信息超载导致检索合适的在线学习资源时遇到了困难;学习者在不同学习环境和序列访问模式上也有不同的学习需求。但是,现有的推荐系统,如基于内容的推荐和协同过滤,没有结合学习者的情境和序列访问模式,推荐结果准确度不高。本文提出了一种结合情境感知、序列模式挖掘和协同过滤算法的混合推荐算法来为学习者推荐学习资源。混合推荐算法中,情境感知被用来整合学习者的情境信息,如知识水平和学习目标;序列模式挖掘被用来对网络日志进行挖掘,发现学习者的序列访问模式;协同过滤被用来根据学习者的情境数据和序列访问模式为目标学习者计算预测并生成建议。实验和应用效果表明,该混合推荐算法推荐的质量和准确性方面优于其他推荐算法。 展开更多
关键词 推荐系统 混合推荐 情境感知 协同过滤 序列模式挖掘
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Preparation and Optical Patterning of Organic-Inorganic Hybrid Color-Filter Films Using Latent Pigments by Utilizing Photo-Acid-Generator and Microwave Irradiation
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作者 T. Ohishi S. Sugawara 《Materials Sciences and Applications》 2014年第14期1079-1090,共12页
Preparation and photo-patterning characteristics of organic-inorganic hybrid thin film containing latent pigment by using photo-acid-generator (PAG) and microwave irradiation have been investigated. The acrylic thin f... Preparation and photo-patterning characteristics of organic-inorganic hybrid thin film containing latent pigment by using photo-acid-generator (PAG) and microwave irradiation have been investigated. The acrylic thin film modified with methoxysilane containing PAG was formed on a glass substrate and irradiated with ultraviolet rays to promote sol-gel reaction by catalytic action of acid which was generated from PAG. And then the film was hardened with microwave irradiation, yielding organic-inorganic hybrid polymer film having hardness, highly transparency and strong adhesion with a glass substrate. Since this reaction only occurred in the optically (UV) irradiated regions, by exploiting the difference between the adhesivenesses of these regions photo-irradiated through photomask with a glass substrate, it was possible to form a patterned film with pitch of 100 to 50 μm by a simple lift-off method. A pigment-containing film using latent pigments (with subtractive three primary colors of coloring materials) and a patterned film were prepared, and it was possible to make these films multi-colored by varying the mixing ratio of the pigments. This multi-colored film-preparation method is effective for simply and efficiently forming a color-filter film by applying optical and microwave irradiation. 展开更多
关键词 Organic-Inorganic Hybrid Film Color filter Photo-patterning LATENT Pigment Photo-Acid-Generator Microwave Lift-Off Method
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基于希尔伯特滤波的可擦笔油墨光谱模式识别
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作者 王晓宾 张傲林 +1 位作者 邹颖芳 杨蕾 《光谱学与光谱分析》 SCIE EI CAS CSCD 北大核心 2024年第5期1338-1345,共8页
文件的真实性是当前诉讼审查阶段的重要工作,可擦笔在司法案件中常被用来进行伪造文书、合同等犯罪行为。针对其油墨成分、笔迹修改等方面的辨识是文件检验领域的重点研究。特殊热感变色颜料是可擦笔油墨的主要成分,其变色原理是随着温... 文件的真实性是当前诉讼审查阶段的重要工作,可擦笔在司法案件中常被用来进行伪造文书、合同等犯罪行为。针对其油墨成分、笔迹修改等方面的辨识是文件检验领域的重点研究。特殊热感变色颜料是可擦笔油墨的主要成分,其变色原理是随着温度变化会产生笔迹的消失与复现,在65℃以上颜色褪去,在-18℃以下颜色复现。对其进行种属认定可以对案件证据的真实性进行鉴别,为案件诉讼过程提供支持。高光谱的超高光谱分辨率对高分子材料具有较好的特征选择性,能够有效的对常见油墨成分进行数据采集。该实验收集22个品牌共45份可擦笔油墨样本,可以分为碳化钨笔珠、子弹头笔珠、全针管、半针管四种类型,统一采集450~950 nm波段的高光谱信息。关于光谱数据背景噪声冗余的问题,选用主成分分析法(PCA)对数据进行降维处理,提取特征变量。基于降维后的数据选用不同类型的希尔伯特变换(HT)进行信号滤波,进一步选择有效信号,提升建模效果。样本识别上选用多层感知器(MLP)和径向基函数神经网络(radial basis function neural network,RBFNN)两种人工神经网络模型,基于23维主成分提取的特征变量类建模准确率分别为81%,84%,通过希尔伯特高通滤波处理后可以将分类准确率提升至88.9%,92%,能够有效提升识别准确率。为进一步区分不同样本的种类,选择Fisher判别分析方法进行建模,各样本原始数据在FDA模型中识别准确率为44%,经最优PCA-HT处理的FDA建模准确率为93.3%,能够区分出不同的可擦笔油墨类型。结果表明,PCA能够在保留光谱有效信息的基础上进行降维,提升模型精度并且缩短运行时间,相较于原始光谱数据建模效果较好,通过希尔伯特变换后的光谱数据能够进一步完善有效光谱信息,使得建模准确率进一步提升。该实验确定PCA-HT-FDA模型为最佳可擦笔油墨高光谱识别模型,能够为司法鉴定人员提供一定参考。 展开更多
关键词 可擦笔 高光谱 滤波器 希尔伯特变换 模式识别
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基于有状态Bloom filter引擎的高速分组检测 被引量:13
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作者 叶明江 崔勇 +1 位作者 徐恪 吴建平 《软件学报》 EI CSCD 北大核心 2007年第1期117-126,共10页
越来越多的网络安全技术通过分析网络分组中的内容来检测报文中是否含有恶意攻击代码.为了能够在线检测攻击,部署在路由器中的分组检测模块对于分组检测的速度也提出了越来越高的要求.虽然在这个领域已有很多研究工作,然而在性能、可扩... 越来越多的网络安全技术通过分析网络分组中的内容来检测报文中是否含有恶意攻击代码.为了能够在线检测攻击,部署在路由器中的分组检测模块对于分组检测的速度也提出了越来越高的要求.虽然在这个领域已有很多研究工作,然而在性能、可扩展性和适用性方面还有很多可研究的空间.提出了一种基于有状态Bloomfilter引擎的高速分组检测方法State-BasedBloomfilterengine(SABFE).通过并行查找Bloomfilter和前缀寄存器堆,以及利用多个并行的Bloomfilter引擎进行流并行检测,达到了较高的吞吐性能.同时,利用快速查找表和前缀寄存器堆保存当前子串的匹配状态来检测长的规则.分析和模拟实验表明:该方法在规则长度增加时依然保持了较高的吞吐性能,可以实现线速的分组检测,同时,极大地减少了硬件资源开销,提高了可扩展性. 展开更多
关键词 网络安全 网络入侵检测 分组检测 串匹配 BLOOM filter
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一种基于Bloom Filter的正则表达式集合快速搜索算法 被引量:4
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作者 徐克付 齐德昱 +1 位作者 郑伟平 钱正平 《华南理工大学学报(自然科学版)》 EI CAS CSCD 北大核心 2009年第4期37-41,共5页
正则表达式搜索算法的性能与从非确定性有限状态自动机(NFA)的初始状态到终止状态的最短路径Lmin成正比,与正则表达式所表达的语言的前缀集合Pref(RE)成反比,而一般情况下Pref(RE)较大,确定Pref(RE)中的元素在目标文本中的出现位置比较... 正则表达式搜索算法的性能与从非确定性有限状态自动机(NFA)的初始状态到终止状态的最短路径Lmin成正比,与正则表达式所表达的语言的前缀集合Pref(RE)成反比,而一般情况下Pref(RE)较大,确定Pref(RE)中的元素在目标文本中的出现位置比较困难.文中提出了一种基于Bloom Filter的正则表达式集合搜索算法,此算法利用BloomFilter集合查询时间与集合大小无关的特点,可以快速准备定位Pref(RE)的出现位置,使得搜索速度不受Pref(RE)的影响,如果采用多个Bloom Filter并行,还可以间接增大Lmin.分析与测试结果表明,该算法较大地加快了正则表达式的搜索速度,对于正则表达式集合,算法性能改善尤其明显,在Lmin较长、Pref(RE)较大时,搜索速度可以提高数倍至数十倍,适合大规模的多正则表达式的快速搜索. 展开更多
关键词 正则表达式匹配 BLOOM filter 自动机 模式匹配
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基于多尺度卷积MSRCR的蒙古族家具纹样增强研究
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作者 廖瑞姬 刘强 +2 位作者 袁云梅 董霙达 多化琼 《林产工业》 北大核心 2024年第4期55-58,共4页
针对蒙古族家具纹样采集过程中,受到环境、设备、人为干扰以及纹样自身风化等因素影响,产生对比度低、亮度异常、纹样模糊、色彩失真退化等情况,本文提出一种基于多尺度卷积MSRCR增强的算法。通过二次导向滤波、多通道多尺度卷积、线性... 针对蒙古族家具纹样采集过程中,受到环境、设备、人为干扰以及纹样自身风化等因素影响,产生对比度低、亮度异常、纹样模糊、色彩失真退化等情况,本文提出一种基于多尺度卷积MSRCR增强的算法。通过二次导向滤波、多通道多尺度卷积、线性加权融合、白平衡等步骤,对MSRCR算法进行改进。结果表明:该方法能有效提升纹样图像质量,改善纹样图像的对比度、亮度,在相关评价指标中也更优。 展开更多
关键词 蒙古族家具纹样 纹样增强 导向滤波 多尺度卷积 MSRCR算法
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基于LTP编码的分数阶Gabor高光谱遥感图像分类
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作者 王亚丽 李丙春 +3 位作者 刘晨 要秀红 代明军 贾森 《电光与控制》 CSCD 北大核心 2024年第11期96-101,共6页
为有效提取高光谱遥感图像的空谱结构特征、增强特征鉴别性及提高分类精度,提出基于局部三元模式编码的分数阶Gabor高光谱遥感图像分类方法。首先,用分数阶三维Gabor滤波器进行局部特征的有效提取;其次,对Gabor相位特征进行局部三元模... 为有效提取高光谱遥感图像的空谱结构特征、增强特征鉴别性及提高分类精度,提出基于局部三元模式编码的分数阶Gabor高光谱遥感图像分类方法。首先,用分数阶三维Gabor滤波器进行局部特征的有效提取;其次,对Gabor相位特征进行局部三元模式编码,以提高特征的可鉴别性;然后,通过随机森林算法对Gabor相位特征进行分类以获得置信度立方体;最后,融合多组基于Gabor的置信立方体,提取具有互补性、强表达性的纹理特征。选择3个训练样本分别在Indian Pines、Salinas、Trento数据集上验证,总体分类精度分别达到63.50%、81.78%、86.89%。实验结果表明,所提的方法具有更好的分类性能。 展开更多
关键词 高光谱图像分类 GABOR滤波器 分数阶滤波器 局部三元模式
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基于改进甲壳虫全域搜索算法的机织物疵点检测
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作者 李杨 张永超 +2 位作者 彭来湖 胡旭东 袁嫣红 《纺织学报》 EI CAS CSCD 北大核心 2024年第10期89-94,共6页
为解决深度学习模型在面对跨场景的织物疵点检测时存在泛化性能差的问题,在甲壳虫全域搜索算法(BAS)的基础上添加了本地搜索能力构建了一种基于甲壳虫算法的混合算法,该算法可具体分为训练阶段和检测阶段。在训练阶段,通过对无疵点织物... 为解决深度学习模型在面对跨场景的织物疵点检测时存在泛化性能差的问题,在甲壳虫全域搜索算法(BAS)的基础上添加了本地搜索能力构建了一种基于甲壳虫算法的混合算法,该算法可具体分为训练阶段和检测阶段。在训练阶段,通过对无疵点织物进行训练构建二维Gabor滤波器,然后使用改进BAS的混合模型对Gabor滤波器的参数进行了优化,使改进后的算法具备全局搜索和局部搜索的能力;在检测阶段,根据在训练阶段获得最佳参数构造Gabor滤波器,对待检测的织物图像进行卷积运算,并对卷积后图像进行二值化处理,最终识别待测试织物是否含有疵点。实验结果表明:该方法的特征提取具有良好的类别区分性,更加集中在疵点范围内,检测准确率可达99.26%,具有良好的稳定性和泛化性能。 展开更多
关键词 深度学习 全域搜索算法 GABOR滤波器 织物疵点检测 泛化性能 图像识别
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基于特征提取和图像分类的螺旋网疵点自动检测
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作者 王博润 张宁 卢雨正 《现代纺织技术》 北大核心 2024年第1期36-44,共9页
为了解决当前螺旋网人工疵点检测效率低、误检率高等问题,提出了一种基于分类思想的螺旋网疵点检测方法。对螺旋网图像提取多模式多尺度的LBP特征,充分表征螺旋网图像的信息,通过构建支持向量机(Support vector machine,SVM)分类器实现... 为了解决当前螺旋网人工疵点检测效率低、误检率高等问题,提出了一种基于分类思想的螺旋网疵点检测方法。对螺旋网图像提取多模式多尺度的LBP特征,充分表征螺旋网图像的信息,通过构建支持向量机(Support vector machine,SVM)分类器实现螺旋网疵点自动检测。结果表明:对于螺旋网疵点图像的局部二值模式(Local binary pattern,LBP)特征,采样半径为2,采样点个数为8时的均匀模式LBP的分类准确率优于其他模式和尺度的LBP,达到了100%,检测速度为0.48 s/张。通过对比不同的特征提取方法和分类器,验证了该文方法对于螺旋网疵点自动检测的适用性,可以实现纺织企业中螺旋网的自动化检测。 展开更多
关键词 高分子滤网 机器视觉 疵点检测 局部二值模式 支持向量机
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一种基于Bloom-filter表项压缩的TCAM业务识别算法 被引量:3
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作者 陈正虎 兰巨龙 +1 位作者 黄万伟 李玉峰 《电子与信息学报》 EI CSCD 北大核心 2011年第9期2212-2218,共7页
在三态内容寻址存储器(Ternary Content Addressable Memory,TCAM)表项宽度和存储容量约束下,该文提出一种基于匹配表项压缩的BF-TCAM算法,采用Bloom-Filter(BF)对匹配关键字进行单字节编码压缩关键字长度,解决了匹配吞吐率低和存储空... 在三态内容寻址存储器(Ternary Content Addressable Memory,TCAM)表项宽度和存储容量约束下,该文提出一种基于匹配表项压缩的BF-TCAM算法,采用Bloom-Filter(BF)对匹配关键字进行单字节编码压缩关键字长度,解决了匹配吞吐率低和存储空间不足问题。针对BF在表项压缩过程带来的冲突率上升问题,引入向量存储空间策略,利用向量存储空间实现多个哈希函数映射,相对于比特向量策略,有利于降低匹配冲突率。测试实验表明,相对于传统的TCAM匹配算法,BF-TCAM算法不但提高了匹配吞吐率和存储空间利用率,同时可有效降低BF压缩产生的冲突率。 展开更多
关键词 三态内容寻址存储器(TCAM) Bloom滤波器(BF) 模式匹配
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Hierarchical particle filter tracking algorithm based on multi-feature fusion 被引量:3
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作者 Minggang Gan Yulong Cheng +1 位作者 Yanan Wang Jie Chen 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2016年第1期51-62,共12页
A hierarchical particle filter(HPF) framework based on multi-feature fusion is proposed.The proposed HPF effectively uses different feature information to avoid the tracking failure based on the single feature in a ... A hierarchical particle filter(HPF) framework based on multi-feature fusion is proposed.The proposed HPF effectively uses different feature information to avoid the tracking failure based on the single feature in a complicated environment.In this approach,the Harris algorithm is introduced to detect the corner points of the object,and the corner matching algorithm based on singular value decomposition is used to compute the firstorder weights and make particles centralize in the high likelihood area.Then the local binary pattern(LBP) operator is used to build the observation model of the target based on the color and texture features,by which the second-order weights of particles and the accurate location of the target can be obtained.Moreover,a backstepping controller is proposed to complete the whole tracking system.Simulations and experiments are carried out,and the results show that the HPF algorithm with the backstepping controller achieves stable and accurate tracking with good robustness in complex environments. 展开更多
关键词 particle filter corner matching multi-feature fusion local binary patterns(LBP) backstepping.
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KGU-SP:一种挖掘标准模式的知识图谱更新方法 被引量:2
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作者 卢菁 陈婉璐 刘丛 《小型微型计算机系统》 CSCD 北大核心 2023年第6期1177-1183,共7页
目前知识图谱更新面临着更新知识数量大、频率高且包含大量错误信息的问题,现存的方法为保证更新效率对知识简单分类,判断方法单一且不考虑知识的语义关联,导致知识更新精确度低.本文提出一种基于标准模式挖掘的知识图谱更新方法,该方... 目前知识图谱更新面临着更新知识数量大、频率高且包含大量错误信息的问题,现存的方法为保证更新效率对知识简单分类,判断方法单一且不考虑知识的语义关联,导致知识更新精确度低.本文提出一种基于标准模式挖掘的知识图谱更新方法,该方法与自动抽取并直接插入的方法不同,利用从现有知识图谱中挖掘出的标准模式进行模拟匹配来筛选正确的知识,并对标准模式挖掘算法进行了改进,提升了筛选的准确性.当大量知识同时进行更新时对挖掘出的标准模式和待更新知识同时向不同的领域空间向量化,计算两者间的向量距离,通过控制阈值筛选正确的知识.在真实的数据集上实验结果证明了本方法的准确性和有效性. 展开更多
关键词 知识图谱 知识更新 标准模式挖掘 知识筛选 模拟匹配
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Electronic Nose Technology Based on Quantum Dot Filters
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作者 Zhenan Li Jie Bao 《Optics and Photonics Journal》 2017年第8期26-32,共7页
The electronic nose with chemical dyes as sensor can react with target gas and have specific color changes. In general, RGB camera collects a group of images to record these changes used for pattern recognition. RGB f... The electronic nose with chemical dyes as sensor can react with target gas and have specific color changes. In general, RGB camera collects a group of images to record these changes used for pattern recognition. RGB filters are not sensitive to the slight color changes, which limits the performance of this kind of electronic nose. This paper demonstrates using quantum dot spec-troscopy technology to solve this problem. Multiple quantum dot filters are placed on the surface of image sensor. When capturing images, there are more response channels of the same incident light than RGB filters. Simulation and experiment both prove that quantum dot filters with appropriate processing are more sensitive to color changes than RGB filters. 展开更多
关键词 QUANTUM DOTS SPECTRUM RGB filterS pattern Recognition
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Avalanching patterns of irregular sand particles in continual discrete flow 被引量:1
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作者 Ren Han Yu-Feng Zhang +3 位作者 Ran Li Quan Chen Jing-Yu Feng Ping Kong 《Chinese Physics B》 SCIE EI CAS CSCD 2020年第2期309-314,共6页
We investigate the flow patterns of irregular sand particles under avalanching mode in a rotating drum by using the spatial filtering velocimetry technique.By exploring the variations of velocity distribution of granu... We investigate the flow patterns of irregular sand particles under avalanching mode in a rotating drum by using the spatial filtering velocimetry technique.By exploring the variations of velocity distribution of granular flow,we find a type of avalanching pattern of irregular sand particles which is similar to that of spherical particles flow.Due to the fact that the initial position of avalanche in this pattern locates at the middle of the drum and the avalanche propagates toward the edge area gradually,we named it as mid-to-edge avalanching pattern.Furthermore,we find another avalanching pattern which slumps from the edge and propagates toward the opposite edge of the flow surface,named as edge-to-edge pattern.By analyzing the temporal and spatial characteristics of these two types of avalanching patterns,we discover that these two types of avalanche patterns are caused by that the avalanching particles constantly perturb the axial adjacent particles.Thus,the particles on the flow surface are involved in avalanching sequentially in order of the axial distance from the initial position. 展开更多
关键词 spatial filterING velocimetry(SFV)method avalanching pattern VELOCITY distribution IRREGULAR PARTICLES
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The Spatial Color Mixing Model of Digital Camouflage Pattern 被引量:7
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作者 Yong ZHANG Shi-qiang XUE +2 位作者 Xiao-jun JIANG Jing-yang MU Yang YI 《Defence Technology(防务技术)》 SCIE EI CAS 2013年第3期157-161,共5页
A spatial color-mixing model based on tricolor angular frequencies is proposed in consideration that the design theory falls behind the application of digital camouflage pattern.The model is based on Fourier transform... A spatial color-mixing model based on tricolor angular frequencies is proposed in consideration that the design theory falls behind the application of digital camouflage pattern.The model is based on Fourier transform and Gaussian low-pass filter(LPF).In the model,the tricolor angular frequencies are introduced to the spatial frequency response function of human color vision,and the effects of atmospheric attenuation and air screen brightness on color mixture are considered.The field test shows that the model can simulate the color-mixing process in the aspects of color-mixing order,and shape and position of color-mixing spot.But the color-mixing spot color is not perfect,which can be improved by optimizing the atmospheric parameters and tricolor cut-off angular frequencies.The model provides a tool for the research on digital camouflage pattern. 展开更多
关键词 混色 空间 图案 迷彩 数码 频率响应函数 色彩视觉 低通滤波器
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Recognition of Partially Occluded Objects Based on Segmentation by Median Filtering of Extended Direction Code
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作者 Wang Yanping Larmagnac Jean-Pierre +1 位作者 Yuan Jie Zhao Hengzhuo 《Wuhan University Journal of Natural Sciences》 CAS 1997年第4期53-56,共4页
The image contour is segmented into lines, arcs and smooth curves by median filtering of extended direction code. Based on this segmentation, a set of new local invariant features are proposed to recognize partially o... The image contour is segmented into lines, arcs and smooth curves by median filtering of extended direction code. Based on this segmentation, a set of new local invariant features are proposed to recognize partially occluded objects, which is more reasonable compared with conventional corner features. The matching results of some typical examples shows that these features are robust ,effective in recognition. 展开更多
关键词 pattern recognition Freeman's code extended code median filtering CORNER
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A novel approach in ECG beat recognition using adaptive neural fuzzy filter
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作者 Glayol Nazari Golpayegani Amir Homayoun Jafari 《Journal of Biomedical Science and Engineering》 2009年第2期80-85,共6页
Accurate and computationally efficient means of electrocardiography (ECG) arrhythmia detec-tion has been the subject of considerable re-search efforts in recent years. Intelligent com-puting tools such as artificial n... Accurate and computationally efficient means of electrocardiography (ECG) arrhythmia detec-tion has been the subject of considerable re-search efforts in recent years. Intelligent com-puting tools such as artificial neural network (ANN) and fuzzy logic approaches are demon-strated to be competent when applied individu-ally to a variety of problems. Recently, there has been a growing interest in combining both of these approaches, and as a result, adaptive neural fuzzy filters (ANFF) [1] have been evolved. This study presents a comparative study of the classification accuracy of ECG signals using (MLP) with back propagation training algorithm, and a new adaptive neural fuzzy filter architec-ture (ANFF) for early diagnosis of ECG ar-rhythmia. ANFF is inherently a feed forward multilayered connectionist network which can learn by itself according to numerical training data or expert knowledge represented by fuzzy if-then rules [1]. In this paper we used an adap-tive neural fuzzy filter as an ECG beat classifier. We combined 3 famous wavelet transforms and used them mid 4 the order AR model coefficient as features. Our results suggest that a new proposed classifier (ANFF) with these features can generalize better than ordinary MLP archi-tecture and also learn better and faster. The results of proposed method show high accu-racy in ECG beat classification (97.6%) with 100% specificity and high sensitivity. 展开更多
关键词 Adaptive Neural Fuzzy filter ECG ARRHYTHMIA Classification pattern RECOGNITION MULTILAYER Perceptron.
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