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Machine learning prediction model for gray-level co-occurrence matrix features of synchronous liver metastasis in colorectal cancer
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作者 Kai-Feng Yang Sheng-Jie Li +1 位作者 Jun Xu Yong-Bin Zheng 《World Journal of Gastrointestinal Surgery》 SCIE 2024年第6期1571-1581,共11页
BACKGROUND Synchronous liver metastasis(SLM)is a significant contributor to morbidity in colorectal cancer(CRC).There are no effective predictive device integration algorithms to predict adverse SLM events during the ... BACKGROUND Synchronous liver metastasis(SLM)is a significant contributor to morbidity in colorectal cancer(CRC).There are no effective predictive device integration algorithms to predict adverse SLM events during the diagnosis of CRC.AIM To explore the risk factors for SLM in CRC and construct a visual prediction model based on gray-level co-occurrence matrix(GLCM)features collected from magnetic resonance imaging(MRI).METHODS Our study retrospectively enrolled 392 patients with CRC from Yichang Central People’s Hospital from January 2015 to May 2023.Patients were randomly divided into a training and validation group(3:7).The clinical parameters and GLCM features extracted from MRI were included as candidate variables.The prediction model was constructed using a generalized linear regression model,random forest model(RFM),and artificial neural network model.Receiver operating characteristic curves and decision curves were used to evaluate the prediction model.RESULTS Among the 392 patients,48 had SLM(12.24%).We obtained fourteen GLCM imaging data for variable screening of SLM prediction models.Inverse difference,mean sum,sum entropy,sum variance,sum of squares,energy,and difference variance were listed as candidate variables,and the prediction efficiency(area under the curve)of the subsequent RFM in the training set and internal validation set was 0.917[95%confidence interval(95%CI):0.866-0.968]and 0.09(95%CI:0.858-0.960),respectively.CONCLUSION A predictive model combining GLCM image features with machine learning can predict SLM in CRC.This model can assist clinicians in making timely and personalized clinical decisions. 展开更多
关键词 colorectal cancer Synchronous liver metastasis Gray-level co-occurrence matrix Machine learning algorithm Prediction model
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Artificial intelligence on diabetic retinopathy diagnosis: an automatic classification method based on grey level co-occurrence matrix and naive Bayesian model 被引量:6
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作者 Kai Cao Jie Xu Wei-Qi Zhao 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2019年第7期1158-1162,共5页
AIM: To develop an automatic tool on screening diabetic retinopathy(DR) from diabetic patients.METHODS: We extracted textures from eye fundus images of each diabetes subject using grey level co-occurrence matrix metho... AIM: To develop an automatic tool on screening diabetic retinopathy(DR) from diabetic patients.METHODS: We extracted textures from eye fundus images of each diabetes subject using grey level co-occurrence matrix method and trained a Bayesian model based on these textures. The receiver operating characteristic(ROC) curve was used to estimate the sensitivity and specificity of the Bayesian model.RESULTS: A total of 1000 eyes fundus images from diabetic patients in which 298 eyes were diagnosed as DR by two ophthalmologists. The Bayesian model was trained using four extracted textures including contrast, entropy, angular second moment and correlation using a training dataset. The Bayesian model achieved a sensitivity of 0.949 and a specificity of 0.928 in the validation dataset. The area under the ROC curve was 0.938, and the 10-fold cross validation method showed that the average accuracy rate is 93.5%.CONCLUSION: Textures extracted by grey level cooccurrence can be useful information for DR diagnosis, and a trained Bayesian model based on these textures can be an effective tool for DR screening among diabetic patients. 展开更多
关键词 GREY level co-occurrence matrix Bayesian textures artificial INTELLIGENCE receiver operating characteristiccurve DIABETIC RETINOPATHY
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Automatic Identification of Butterfly Species Based on Gray-Level Co-occurrence Matrix Features of Image Block 被引量:4
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作者 XUE Ankang LI Fan XIONG Yin 《Journal of Shanghai Jiaotong university(Science)》 EI 2019年第2期220-225,共6页
In recent years, automatic identification of butterfly species arouses more and more attention in different areas. Because most of their larvae are pests, this research is not only meaningful for the popularization of... In recent years, automatic identification of butterfly species arouses more and more attention in different areas. Because most of their larvae are pests, this research is not only meaningful for the popularization of science but also important to the agricultural production and the environment. Texture as a notable feature is widely used in digital image recognition technology; for describing the texture, an extremely effective method, graylevel co-occurrence matrix(GLCM), has been proposed and used in automatic identification systems. However,according to most of the existing works, GLCM is computed by the whole image, which likely misses some important features in local areas. To solve this problem, this paper presents a new method based on the GLCM features extruded from three image blocks, and a weight-based k-nearest neighbor(KNN) search algorithm used for classifier design. With this method, a butterfly classification system works on ten butterfly species which are hard to identify by shape features. The final identification accuracy is 98%. 展开更多
关键词 automatic identification butterfly species gray-level co-occurrence matrix(GLCM) features of image block
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Binary Image Steganalysis Based on Distortion Level Co-Occurrence Matrix 被引量:2
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作者 Junjia Chen Wei Lu +4 位作者 Yuileong Yeung Yingjie Xue Xianjin Liu Cong Lin Yue Zhang 《Computers, Materials & Continua》 SCIE EI 2018年第5期201-211,共11页
In recent years,binary image steganography has developed so rapidly that the research of binary image steganalysis becomes more important for information security.In most state-of-the-art binary image steganographic s... In recent years,binary image steganography has developed so rapidly that the research of binary image steganalysis becomes more important for information security.In most state-of-the-art binary image steganographic schemes,they always find out the flippable pixels to minimize the embedding distortions.For this reason,the stego images generated by the previous schemes maintain visual quality and it is hard for steganalyzer to capture the embedding trace in spacial domain.However,the distortion maps can be calculated for cover and stego images and the difference between them is significant.In this paper,a novel binary image steganalytic scheme is proposed,which is based on distortion level co-occurrence matrix.The proposed scheme first generates the corresponding distortion maps for cover and stego images.Then the co-occurrence matrix is constructed on the distortion level maps to represent the features of cover and stego images.Finally,support vector machine,based on the gaussian kernel,is used to classify the features.Compared with the prior steganalytic methods,experimental results demonstrate that the proposed scheme can effectively detect stego images. 展开更多
关键词 Binary image steganalysis informational security embedding distortion distortion level map co-occurrence matrix support vector machine.
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3D Gray Level Co-Occurrence Matrix Based Classification of Favor Benign and Borderline Types in Follicular Neoplasm Images 被引量:1
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作者 Oranit Boonsiri Kiyotada Washiya +1 位作者 Kota Aoki Hiroshi Nagahashi 《Journal of Biosciences and Medicines》 2016年第3期51-56,共6页
Since the efficiency of treatment of thyroid disorder depends on the risk of malignancy, indeterminate follicular neoplasm (FN) images should be classified. The diagnosis process has been done by visual interpretation... Since the efficiency of treatment of thyroid disorder depends on the risk of malignancy, indeterminate follicular neoplasm (FN) images should be classified. The diagnosis process has been done by visual interpretation of experienced pathologists. However, it is difficult to separate the favor benign from borderline types. Thus, this paper presents a classification approach based on 3D nuclei model to classify favor benign and borderline types of follicular thyroid adenoma (FTA) in cytological specimens. The proposed method utilized 3D gray level co-occurrence matrix (GLCM) and random forest classifier. It was applied to 22 data sets of FN images. Furthermore, the use of 3D GLCM was compared with 2D GLCM to evaluate the classification results. From experimental results, the proposed system achieved 95.45% of the classification. The use of 3D GLCM was better than 2D GLCM according to the accuracy of classification. Consequently, the proposed method probably helps a pathologist as a prescreening tool. 展开更多
关键词 Thyroid Follicular Lesion 3D Gray Level co-occurrence matrix Random Ferest Classifier
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A Combination of Feature Selection and Co-occurrence Matrix Methods for Leukocyte Recognition System
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作者 Li Na Arlends Chris Bagus Mulyawan 《Journal of Software Engineering and Applications》 2012年第12期101-106,共6页
A leukocyte recognition system, as part of a differential blood counter system, is very important in hematology field. In this paper, the propose system aims to automatically classify the white blood cells (leukocytes... A leukocyte recognition system, as part of a differential blood counter system, is very important in hematology field. In this paper, the propose system aims to automatically classify the white blood cells (leukocytes) on a given microscopic image. The classifications of leukocytes are performed based on the combination of color and texture features of the blood cell images. The developed system classifies the leukocytes in one of the five categories (neutrophils, eosinophils, basophils, lymphocytes, and monocytes). In the preprocessing stage, the system starts with converting the microscopic images from Red Green Blue (RGB) color space to Hue Saturation Value (HSV) color space. Next, the system splits the Hue and Saturation features from the Value feature. For both Hue and Saturation features, the system processes their color information using the Feature Selection method and the Window Cropping method;while the Value feature is processed by its texture information using the Co-occurrence matrix method. The final recognition stage is performed using the Euclidean distance method. The combination of the Feature Selection and Co-occurrence Matrix methods gives the best overall recognition accuracies for classifying leukocyte images. 展开更多
关键词 LEUKOCYTE recognition WHITE BLOOD cell MICROSCOPIC image Feature selection co-occurrence matrix
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Material microstructures analyzed by using gray level Co-occurrence matrices 被引量:1
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作者 胡延苏 王志军 +2 位作者 樊晓光 李俊杰 高昂 《Chinese Physics B》 SCIE EI CAS CSCD 2017年第9期483-490,共8页
The mechanical properties of materials greatly depend on the microstructure morphology. The quantitative characterization of material microstructures is essential for the performance prediction and hence the material ... The mechanical properties of materials greatly depend on the microstructure morphology. The quantitative characterization of material microstructures is essential for the performance prediction and hence the material design. At present,the quantitative characterization methods mainly rely on the microstructure characterization of shape, size, distribution,and volume fraction, which related to the mechanical properties. These traditional methods have been applied for several decades and the subjectivity of human factors induces unavoidable errors. In this paper, we try to bypass the traditional operations and identify the relationship between the microstructures and the material properties by the texture of image itself directly. The statistical approach is based on gray level Co-occurrence matrix(GLCM), allowing an objective and repeatable study on material microstructures. We first present how to identify GLCM with the optimal parameters, and then apply the method on three systems with different microstructures. The results show that GLCM can reveal the interface information and microstructures complexity with less human impact. Naturally, there is a good correlation between GLCM and the mechanical properties. 展开更多
关键词 microstructures quantitative characterization mechanical properties gray level co-occurrence matrix
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ColorMatrix提高PET的阻隔性能
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作者 李含(译) 《塑料助剂》 2009年第5期58-58,共1页
ColorMatrix推出了Amosorb SolO2高性能PET阻隔技术。根据Color Matrix的说法,这一新技术增加了产品的保护能力。特别使一些对氧敏感的饮料保质期得到延长.如啤酒、葡萄酒和果汁。
关键词 阻隔性能 PET matrix 阻隔技术 color 保护能力 保质期 葡萄酒
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Orthogonal projection based subspace identification against colored noise 被引量:2
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作者 Jie HOU Tao LIU Fengwei CHEN 《Control Theory and Technology》 EI CSCD 2017年第1期69-77,共9页
In this paper, a bias-eliminated subspace identification method is proposed for industrial applications subject to colored noise. Based on double orthogonal projections, an identification algorithm is developed to eli... In this paper, a bias-eliminated subspace identification method is proposed for industrial applications subject to colored noise. Based on double orthogonal projections, an identification algorithm is developed to eliminate the influence of colored noise for consistent estimation of the extended observability matrix of the plant state-space model. A shift-invariant approach is then given to retrieve the system matrices from the estimated extended observability matrix. The persistent excitation condition for consistent estimation of the extended observability matrix is analyzed. Moreover, a numerical algorithm is given to compute the estimation error of the estimated extended observability matrix. Two illustrative examples are given to demonstrate the effectiveness and merit of the proposed method. 展开更多
关键词 Subspace identification colored noise orthogonal projection extended observability matrix consistent estimation
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Detecting Double JPEG Compressed Color Images via an Improved Approach 被引量:1
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作者 Xiaojie Zhao Xiankui Meng +2 位作者 Ruyong Ren Shaozhang Niu Zhenguang Gao 《Computers, Materials & Continua》 SCIE EI 2023年第4期1765-1781,共17页
Detecting double Joint Photographic Experts Group (JPEG) compressionfor color images is vital in the field of image forensics. In previousresearches, there have been various approaches to detecting double JPEGcompress... Detecting double Joint Photographic Experts Group (JPEG) compressionfor color images is vital in the field of image forensics. In previousresearches, there have been various approaches to detecting double JPEGcompression with different quantization matrices. However, the detectionof double JPEG color images with the same quantization matrix is stilla challenging task. An effective detection approach to extract features isproposed in this paper by combining traditional analysis with ConvolutionalNeural Networks (CNN). On the one hand, the number of nonzero pixels andthe sum of pixel values of color space conversion error are provided with 12-dimensional features through experiments. On the other hand, the roundingerror, the truncation error and the quantization coefficient matrix are used togenerate a total of 128-dimensional features via a specially designed CNN. Insuch aCNN, convolutional layers with fixed kernel of 1×1 and Dropout layersare adopted to prevent overfitting of the model, and an average pooling layeris used to extract local characteristics. In this approach, the Support VectorMachine (SVM) classifier is applied to distinguishwhether a given color imageis primarily or secondarily compressed. The approach is also suitable for thecase when customized needs are considered. The experimental results showthat the proposed approach is more effective than some existing ones whenthe compression quality factors are low. 展开更多
关键词 color image forensics double JPEG compression detection the same quantization matrix CNN
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Effect of Different Conditions on the Structural Color of Konjac Glucomannan Particles 被引量:1
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作者 谭小丹 黄荣勋 +5 位作者 穆若郡 谢丙清 袁毅 王敏 陈涵 庞杰 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2016年第10期1525-1531,共7页
In this paper,molecular dynamics simulation was applied to synthesize a layered structural color from Konjac glucomannan(KGM) and the effect of particle diameter and temperature were investigated. A series of method... In this paper,molecular dynamics simulation was applied to synthesize a layered structural color from Konjac glucomannan(KGM) and the effect of particle diameter and temperature were investigated. A series of methods such as high voltage electric field treatment,the transfer matrix method and the CIE standard colorimetric system were simulated to obtain the chromaticity coordinates and to analyze the color changes of KGM particles. The results revealed that as the particle diameter increases,the structural color of KGM particles deflects towards the yellow wavelength within the visible spectrum; and as the reaction temperature rises,the structural color deflects towards the blue and violet wavelengths within the visible spectrum. 展开更多
关键词 Konjac glucomannan(KGM) structural color transfer matrix method CIE standard chromaticity
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Hybrid Color Texture Features Classification Through ANN for Melanoma
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作者 Saleem Mustafa Arfan Jaffar +3 位作者 Muhammad Waseem Iqbal Asma Abubakar Abdullah S.Alshahrani Ahmed Alghamdi 《Intelligent Automation & Soft Computing》 SCIE 2023年第2期2205-2218,共14页
Melanoma is of the lethal and rare types of skin cancer.It is curable at an initial stage and the patient can survive easily.It is very difficult to screen all skin lesion patients due to costly treatment.Clinicians ar... Melanoma is of the lethal and rare types of skin cancer.It is curable at an initial stage and the patient can survive easily.It is very difficult to screen all skin lesion patients due to costly treatment.Clinicians are requiring a correct method for the right treatment for dermoscopic clinical features such as lesion borders,pigment networks,and the color of melanoma.These challenges are required an automated system to classify the clinical features of melanoma and non-melanoma disease.The trained clinicians can overcome the issues such as low contrast,lesions varying in size,color,and the existence of several objects like hair,reflections,air bubbles,and oils on almost all images.Active contour is one of the suitable methods with some drawbacks for the segmentation of irre-gular shapes.An entropy and morphology-based automated mask selection is pro-posed for the active contour method.The proposed method can improve the overall segmentation along with the boundary of melanoma images.In this study,features have been extracted to perform the classification on different texture scales like Gray level co-occurrence matrix(GLCM)and Local binary pattern(LBP).When four different moments pull out in six different color spaces like HSV,Lin RGB,YIQ,YCbCr,XYZ,and CIE L*a*b then global information from different colors channels have been combined.Therefore,hybrid fused texture features;such as local,color feature as global,shape features,and Artificial neural network(ANN)as classifiers have been proposed for the categorization of the malignant and non-malignant.Experimentations had been carried out on datasets Dermis,DermQuest,and PH2.The results of our advanced method showed super-iority and contrast with the existing state-of-the-art techniques. 展开更多
关键词 Gray level co-occurrence matrix local binary pattern artificial neural networks support vector machines color skin cancer dermoscopic
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Chemical properties of colored dissolved organic matter in the sea-surface microlayer and subsurface water of Jiaozhou Bay, China in autumn and winter
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作者 ZHANG Jing YANG Guipeng 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2013年第6期26-39,共14页
The distribution and chemical properties of chromophoric dissolved organic matter (CDOM) in the Jiaozhou Bay, China were examined during four cruises in 2010-2011. The influence of freshwater and industrial and muni... The distribution and chemical properties of chromophoric dissolved organic matter (CDOM) in the Jiaozhou Bay, China were examined during four cruises in 2010-2011. The influence of freshwater and industrial and municipal sewage along the eastern coast of the bay was clearly evident as CDOM level- s (defined as a30s), and dissolved organic carbon (DOC) concentrations were well correlated with salinity during all the cruises. Moreover, DOC concentrations were significantly correlated with chlorophyll a con- centrations in the surface microlayer as well as in the subsurface water. The concentrations of DOC and CDOM displayed a gradually decreasing trend from the northwestern and eastern coast to the central hay, and the values and gradients of their concentrations on the eastern coast were generally higher than those on the western coast. In addition, CDOM and DOC levels were generally higher in the surface microlayer than in the subsurface water. In comparison with DOC, CDOM exhibited a greater extent of enrichment in the microlayer in each cruise, with average enrichment factor (EF) values of 1.38 and 1.84, respectively. Four fluorescent components were identified from the surface microlayer and subsurface water samples and could be distinguished as peak A, peak T, peak B and peak M. For all the cruises, peak A levels were higher in the surface microlayer than in the subsurface water. This pattern of variation might be attributed to the terrestrial input. 展开更多
关键词 colored dissolved organic matter (CDOM) absorption coefficient dissolved organic carbon (DOC) fluorescence excitation emission matrix (EEMs) Iiaozhou Bay
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传统纺织品图案的屈曲矫正与再生设计 被引量:2
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作者 石文慧 朱海峰 +2 位作者 蒋汶秦 倪嘉陆 徐平华 《服装学报》 北大核心 2025年第1期40-45,共6页
为解决传统纺织品成像屈曲造成的图案变形问题,探究基于内容的图像拉伸方法,同时对矫正后的图案进行再生设计。通过计算图像的能量矩阵得到端到端的最小能量曲线,利用周边信息计算出填补像素;通过路径动态规划的迭代来实现图像在水平和... 为解决传统纺织品成像屈曲造成的图案变形问题,探究基于内容的图像拉伸方法,同时对矫正后的图案进行再生设计。通过计算图像的能量矩阵得到端到端的最小能量曲线,利用周边信息计算出填补像素;通过路径动态规划的迭代来实现图像在水平和垂直方向上的内容填充,从而实现屈曲图像的矫正。利用边缘检测、矢量化操作和颜色聚类等方法,对纹样和色彩进行再生设计。将基于能量矩阵矫正图案屈曲的方法与其他常用的形态矫正算法进行对比。结果表明,基于能量矩阵矫正图案屈曲的方法在保全内容的前提下,能够有效实现屈曲图案的形态矫正。借助图像处理技术,可以提取矫正后图案的纹样和色彩,应用于当代产品创新设计。 展开更多
关键词 传统图案 屈曲 矫正 色彩提取 能量矩阵
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一类图邻接矩阵的行列式及积和式
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作者 马海成 《吉林大学学报(理学版)》 北大核心 2025年第5期1348-1355,共8页
基于图上的Sachs子图计算图邻接矩阵的行列式与积和式的一个公式,分别给出计算图邻接矩阵的行列式与积和式的一个删点的递推公式,并利用这些递推公式,分别给出计算彩球图邻接矩阵的行列式与积和式的方法.结果表明,彩球图邻接矩阵的行列... 基于图上的Sachs子图计算图邻接矩阵的行列式与积和式的一个公式,分别给出计算图邻接矩阵的行列式与积和式的一个删点的递推公式,并利用这些递推公式,分别给出计算彩球图邻接矩阵的行列式与积和式的方法.结果表明,彩球图邻接矩阵的行列式等于一个具有16个变量的函数的全微分,彩球图邻接矩阵的积和式等于一个具有4个变量的函数的全微分. 展开更多
关键词 邻接矩阵 行列式 积和式 彩球图 全微分
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基于托普利兹信号子空间匹配度量的信源数估计方法
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作者 生雪莉 李德文 +1 位作者 曹然 李理 《哈尔滨工程大学学报》 北大核心 2025年第10期2077-2083,共7页
为解决有色噪声和快拍数不足场景下难以准确估计信源数的问题,本文提出一种基于托普利兹信号子空间匹配度量的信源数估计方法。利用托普利兹理论优化样本协方差矩阵,并提取前G个特征向量构成信号子空间。通过信号子空间匹配度量模型评... 为解决有色噪声和快拍数不足场景下难以准确估计信源数的问题,本文提出一种基于托普利兹信号子空间匹配度量的信源数估计方法。利用托普利兹理论优化样本协方差矩阵,并提取前G个特征向量构成信号子空间。通过信号子空间匹配度量模型评估采样数据投影矩阵与信号子空间投影矩阵之间的距离,并以两者的最小距离值作为需估计的信源数。本文方法在保留信号子空间匹配度量优势的同时提高了样本协方差矩阵的估计精度。仿真结果表明,当快拍数大于16或信噪比超过5 dB时,本文方法正确估计信源数的概率高于92%,显著优于现有方法,验证了其有效性。 展开更多
关键词 托普利兹 有色噪声 信号子空间 匹配度量 样本协方差矩阵 投影矩阵 信源数
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冷热循环对树脂-陶瓷复合材料颜色稳定性的影响
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作者 赵珂宁 王洁 孙健 《口腔材料器械杂志》 2025年第3期137-141,152,共6页
目的比较不同透明度、厚度、材料种类对CAD/CAM树脂-陶瓷复合材料(RMCs)冷热循环前后光学性能及其变化情况的影响,以评价这类新型材料的颜色稳定性。方法选取高透明度与低透明度的3种RMCs:Hy(Hyramic),LU(Lava Ultimate),VE(Vita Enamic... 目的比较不同透明度、厚度、材料种类对CAD/CAM树脂-陶瓷复合材料(RMCs)冷热循环前后光学性能及其变化情况的影响,以评价这类新型材料的颜色稳定性。方法选取高透明度与低透明度的3种RMCs:Hy(Hyramic),LU(Lava Ultimate),VE(Vita Enamic)作为实验组,以二硅酸锂玻璃陶瓷UP(UP.CAD)作为对照组,厚度分组为0.5 mm与1.0 mm。分别在冷热循环0、10000、20000、30000、40000次时(高温55℃,低温5℃,停留时间30 s)使用分光光度计检测L^(*),a^(*),b^(*)值,计算ΔE_(00)值,并进行统计学分析。结果不同透明度和厚度显著影响陶瓷材料的L^(*),a^(*),b^(*)值(P<0.05)。不同材料间,L^(*)值依次为:LU>VE>UP>Hy;a^(*)值依次为:Hy>VE>UP>LU;b^(*)值依次为:VE>Hy>UP>LU。冷热循环10000次后Hy的ΔE_(00)超过50%人群可接受阈值,0.5 mm LT LU与0.5 mm HT VE的ΔE_(00)分别在冷热循环20000次、30000次后超过50%人群可感知阈值。其余材料经40000次冷热循环后的ΔE_(00)均未超过可感知阈值。结论树脂-陶瓷复合材料冷热循环前后的光学性能与材料的透明度、厚度、种类密切相关。透明度越高,厚度越厚,树脂基陶瓷越暗、越红、越黄。树脂-陶瓷复合材料中Hy、LU、VE的颜色改变分别于冷热循环10000、20000、30000次后可被感知到,其颜色稳定性劣于玻璃陶瓷。 展开更多
关键词 CAD/CAM树脂陶瓷复合材料 冷热循环 光学性能 颜色稳定性
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Gray Fabric Defect Detection Based on Statistical Template Matching
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作者 LI Saisai YU Haiyan WANG Junhua 《Journal of Donghua University(English Edition)》 2025年第6期594-605,共12页
To address the high cost of online detection equipment and the low adaptability and accuracy of online detection models that are caused by uneven lighting,high noise,low contrast and so on,a block-based template match... To address the high cost of online detection equipment and the low adaptability and accuracy of online detection models that are caused by uneven lighting,high noise,low contrast and so on,a block-based template matching method incorporating fabric texture characteristics is proposed.Firstly,the template image set is evenly divided into N groups of sub-templates at the same positions to mitigate the effects of image illumination,reduce the model computation,and enhance the detection speed,with all image blocks being preprocessed.Then,the feature value information is extracted from the processed set of subtemplates at the same position,extracting two gray-level cooccurrence matrix(GLCM)feature values for each image block.These two feature values are then fused to construct a matching template.The mean feature value of all image blocks at the same position is calculated and used as the threshold for template detection,enabling automatic selection of template thresholds for different positions.Finally,the feature values of the image blocks in the experimental set are traversed and matched with subtemplates at the same positions to obtain fabric defect detection results.The detection experiments are conducted on a platform that simulates a fabric weaving environment,using defective gray fabrics from a weaving factory as the detected objects.The outcomes demonstrate the efficacy of the proposed method in detecting defects in gray fabrics,the mitigation of the impact of uneven external lighting on detection outcomes,and the enhancement of detection accuracy and adaptability. 展开更多
关键词 defect detection gray-level co-occurrence matrix(GLCM) template matching gray fabric feature extraction online detection
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Automatic classification of coastal sand dunes in the Namib Desert through the texture analysis approach
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作者 JIN Zikai LI Fayuan +2 位作者 LIU Lulu JIAO Haoyang CUI Lingzhou 《Journal of Arid Land》 2025年第8期1168-1187,共20页
Texture analysis methods offer substantial advantages and potential in examining macro-topographic features of dunes.Despite these advantages,comprehensive approaches that integrate digital elevation model(DEM)with qu... Texture analysis methods offer substantial advantages and potential in examining macro-topographic features of dunes.Despite these advantages,comprehensive approaches that integrate digital elevation model(DEM)with quantitative texture features have not been fully developed.This study introduced an automatic classification framework for dunes that combines texture and topographic features and validated it through a typical coastal aeolian landform,namely,dunes in the Namib Desert.A three-stage approach was outlined:(1)segmentation of dune units was conducted using digital terrain analysis;(2)six texture features(angular second moment,contrast,correlation,variance,entropy,and inverse difference moment)were extracted from the gray-level co-occurrence matrix(GLCM)and subsequently quantified;and(3)texture–topographic indices were integrated into the random forest(RF)model for classification.The results show that the RF model fused with texture features can accurately identify dune morphological characteristics;through accuracy evaluation and remote sensing image verification,the overall accuracy reaches 78.0%(kappa coefficient=0.72),outperforming traditional spectral-based methods.In addition,spatial analysis reveals that coastal dunes exhibit complex texture patterns,with texture homogeneity being closely linked to dune-type transitions.Specifically,homogeneous textures correspond to simple and stable forms such as barchans,while heterogeneous textures are associated with complex or composite dunes.The complexity,periodicity,and directionality of texture features are highly consistent with the spatial distribution of dunes.Validation using high-resolution remote sensing imagery(Sentinel-2)further confirms that the method effectively clusters similar dunes and distinguishes different dune types.Additionally,the dune classification results have a good correspondence with changes in near-surface wind regimes.Overall,the findings suggest that texture features derived from DEM can accurately capture the dynamic characteristics of dune morphology,offering a novel approach for automatic dune classification.Compared with traditional methods,the developed approach facilitates large-scale and high-precision dune mapping while reducing the workload of manual interpretation,thus advancing research on aeolian geomorphology. 展开更多
关键词 coastal dune topographic texture random forest digital elevation model(DEM) dune classification gray-level co-occurrence matrix(GLCM)
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河流输入决定着水源地水库DOM组成的时空变异
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作者 张辰雪 段梦伟 +3 位作者 严诺霄 仇志强 唐登淼 刘东 《光谱学与光谱分析》 北大核心 2025年第4期1175-1182,共8页
流域经济发展会对饮用水源地水库的水质产生剧烈影响,其中一个重要方面是通过河流输入加剧溶解性有机物(DOM)污染,而关于河流输入对水源地水库DOM组成时空变异影响尚缺乏系统研究。基于不同季节溧阳沙河水库及入库河流的同步现场采样,... 流域经济发展会对饮用水源地水库的水质产生剧烈影响,其中一个重要方面是通过河流输入加剧溶解性有机物(DOM)污染,而关于河流输入对水源地水库DOM组成时空变异影响尚缺乏系统研究。基于不同季节溧阳沙河水库及入库河流的同步现场采样,通过对有色溶解有机物(CDOM)三维荧光光谱的平行因子分析等方法,探究了沙河水库中DOM组成的时空变异特征及河流输入的影响。结果表明:(1)水库DOM包含腐殖质C1、类蛋白酪氨酸C2、类蛋白色氨酸C3和陆源腐殖质C4四种组分,且C2在大部分点位的占比超过50%。(2)水库DOM组成具有十分明显的季节变化特征,腐殖质DOM组分含量均在春季时最低;对主要组分C2,春夏秋冬含量分别为53.11%、35.22%、60.05%和57.88%。(3)河流输入对水库DOM空间分布具有决定性影响,除了主要来源于生活污水的酪氨酸组分C2,其他组分含量均在河口区域较高。尽管河流向水库输入的DOM以陆源腐殖质C1为主(春夏秋冬占比分别为28.80%、30.51%、27.11%和22.19%),但沙河水库DOM腐殖质化程度较低,即沙河水库DOM以自生源为主。水库自生源DOM主要与藻类增殖有关,类蛋白色氨酸C3组分与叶绿素(Chl-a)含量线性显著正相关(R2=0.51,p<0.01)。这些研究结果对改善水源地水库水质、降低有机污染和保障居民饮用水安全具有十分重要的意义。 展开更多
关键词 沙河水库 溶解性有机物 有色溶解性有机物 三维荧光光谱 平行因子分析
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