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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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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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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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Detecting Double JPEG Compressed Color Images via an Improved Approach
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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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基于Distance-2算法的并行Jacobian矩阵计算及其在耦合问题中的应用
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作者 刘礼勋 张汉 +4 位作者 彭心茹 窦沁榕 邬颖杰 郭炯 李富 《原子能科学技术》 EI CAS CSCD 北大核心 2024年第6期1201-1209,共9页
并行Newton-Krylov方法是求解大规模多物理耦合问题的有效方法,如何高效自动计算Jacobian矩阵是一大难点。利用有限差分方法,可避免推导Jacobian矩阵的表达式,实现矩阵的自动计算。现有工作表明,在串行环境下利用矩阵的稀疏性和图着色算... 并行Newton-Krylov方法是求解大规模多物理耦合问题的有效方法,如何高效自动计算Jacobian矩阵是一大难点。利用有限差分方法,可避免推导Jacobian矩阵的表达式,实现矩阵的自动计算。现有工作表明,在串行环境下利用矩阵的稀疏性和图着色算法,Jacobian矩阵的计算效率可提高至少1个量级。但在并行环境下,串行着色算法失效,需采用相应的并行着色算法。本研究将图论领域的Distance-2算法应用于Jacobian矩阵的并行着色。通过求解一个简化多物理耦合问题检验了该并行算法的正确性和计算效率。测试结果表明,该并行算法得到的Jacobian矩阵完全正确;着色数随着并行核数的增加略微有所增加,100个进程下并行效率为56%;基于该算法求解多物理耦合问题,其计算时间和Krylov迭代次数较JFNK减少了约1/2。 展开更多
关键词 Newton-Krylov方法 稀疏Jacobian矩阵 图着色 有限差分 分布式并行计算
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基于相机RGB值的光谱反射率重建方法研究 被引量:1
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作者 张飞 刘珩 +4 位作者 杨洁 渠立永 吕琪 黄伟 李浩 《兵器装备工程学报》 CAS CSCD 北大核心 2024年第2期284-290,共7页
光谱反射率重建技术可实现背景颜色数据准确校正和复制还原,以此为基础可设计实施高融合迷彩,为机动装备在不同背景环境下提供有效防护屏障,具有重要价值。参照光谱成像技术特点,根据颜色形成原理和三刺激值定量计算公式,通过控制单一... 光谱反射率重建技术可实现背景颜色数据准确校正和复制还原,以此为基础可设计实施高融合迷彩,为机动装备在不同背景环境下提供有效防护屏障,具有重要价值。参照光谱成像技术特点,根据颜色形成原理和三刺激值定量计算公式,通过控制单一变量法设计实验方案,提出加权平均光谱反射率重建方法(TWA),利用相机和光谱仪分别获取训练样本的成像系统响应值(RGB)和光谱反射率数据,对所提取的样本RGB值和光谱反射率数据分别采用传统最小二乘法(OLS)、正则化最小二乘法(RLS)、偏最小二乘法(PLS)、主成分分析法(PCA)和本文中提出的加权平均法(TWA)进行光谱反射率重建训练,获得光谱重建矩阵,最后利用光谱重建矩阵对测试样本响应值进行光谱反射率重建,并对实验结果进行分析,对比不同方法的光谱反射率重建效果。研究结果表明,加权平均法在光谱均方根误差SRMSE、平均拟合优度系数GFC、平均色差等指标上效果更优,重建所得光谱反射率精度更高,颜色校正效果更佳。 展开更多
关键词 光谱反射率 加权平均法 重建矩阵 光谱曲线 颜色校正
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基于前景提取与多特征决策融合的电力线触树放电痕迹识别
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作者 邵楠 王连辉 +1 位作者 梁栋 邹国锋 《集成电路与嵌入式系统》 2024年第8期35-43,共9页
针对电力线路智能化巡检中难以准确辨识电力线触碰树木遗留痕迹,无法为事故防治和责任划分提供可靠依据的难题,提出一种基于前景区域提取与多特征决策融合的电力线放电痕迹识别方法。首先,搭建中压线路触树放电实验平台,采集导线表面放... 针对电力线路智能化巡检中难以准确辨识电力线触碰树木遗留痕迹,无法为事故防治和责任划分提供可靠依据的难题,提出一种基于前景区域提取与多特征决策融合的电力线放电痕迹识别方法。首先,搭建中压线路触树放电实验平台,采集导线表面放电遗留痕迹,构建图像集。然后,提出融合纹理稀疏性与对数变换的去阴影算法,消除阴影区干扰;进一步提出融合全局阈值和自适应阈值分割的目标初始框选取策略,解决了GrabCut算法中初始框无法自动确定的问题,实现复杂背景下导线痕迹的自动精准分割。最后,提取导线的纹理和颜色特征,通过多SVM决策融合实现导线痕迹识别。实验结果表明,所提方法平均识别准确率达到88.39%,证明了所提识别方法的有效性。 展开更多
关键词 树线放电故障 痕迹识别 GRABCUT 灰度共生矩阵 颜色矩 决策融合
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色彩矩阵在体育节目转播中的应用
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作者 陈辉 《电视技术》 2024年第5期158-160,共3页
体育节目转播对于电视画面的质量有较高的要求。色彩矩阵调整是提高画面质量的关键技术之一。应用色彩矩阵技术,能够提高体育节目转播的画面表现力,从而带给观众良好的视觉感受与体验。基于此,探讨体育节目转播中色彩矩阵的应用,阐述色... 体育节目转播对于电视画面的质量有较高的要求。色彩矩阵调整是提高画面质量的关键技术之一。应用色彩矩阵技术,能够提高体育节目转播的画面表现力,从而带给观众良好的视觉感受与体验。基于此,探讨体育节目转播中色彩矩阵的应用,阐述色彩矩阵技术的原理并分析其应用方法,希望能够为体育节目转播画面表现力的提高提供参考。 展开更多
关键词 体育节目 色彩矩阵 画面调色
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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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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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空域色噪声下基于张量Vandermonde因子矩阵重构的MIMO雷达角度估计
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作者 陈金立 唐熠君 +1 位作者 朱熙铖 李家强 《中国电子科学研究院学报》 北大核心 2023年第10期873-881,共9页
本文提出了一种空域色噪声环境下基于张量Vandermonde因子矩阵重构的多输入多输出(Multiple Input Multiple Output, MIMO)雷达角度估计方法。该方法首先将不同脉冲的匹配滤波输出进行互相关以实现对接收信号的去噪处理;然后,根据因子... 本文提出了一种空域色噪声环境下基于张量Vandermonde因子矩阵重构的多输入多输出(Multiple Input Multiple Output, MIMO)雷达角度估计方法。该方法首先将不同脉冲的匹配滤波输出进行互相关以实现对接收信号的去噪处理;然后,根据因子矩阵先验结构信息建立具有Vandermonde约束的四阶张量典范分解/并行因子分析(Canonical Decomposition/Parallel Factor Analysis, CANDECOMP/PARAFAC)模型,并推导了基于约束交替最小二乘(Alternating Least Squares, ALS)的迭代求解方法,在交替迭代过程中充分利用因子矩阵的Vandermonde结构,通过构造Toeplitz矩阵并进行Vandermonde分解的方式获得因子矩阵估计值;最后,通过最小二乘拟合方法估计目标角度。仿真结果表明本文算法能够有效提高MIMO雷达在空域色噪声下的角度估计性能。 展开更多
关键词 MIMO雷达 空域色噪声 Vandermonde因子矩阵 Vandermonde分解 角度估计
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基于噪声圆形特性的宽带相干信号DOA估计方法
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作者 孙志国 王杰 +2 位作者 孙溶辰 白永珍 李齐衡 《系统工程与电子技术》 EI CSCD 北大核心 2023年第9期2667-2672,共6页
针对色噪声下基于差分去噪的宽带相干信号波达方向(direction of arrival,DOA)估计方法对相干信源数有限制的问题,提出一种基于噪声圆形特性去噪和Toeplitz矩阵重构的估计算法。首先,对接收到的信号求取协方差矩阵,利用噪声的圆形特性... 针对色噪声下基于差分去噪的宽带相干信号波达方向(direction of arrival,DOA)估计方法对相干信源数有限制的问题,提出一种基于噪声圆形特性去噪和Toeplitz矩阵重构的估计算法。首先,对接收到的信号求取协方差矩阵,利用噪声的圆形特性消除噪声。为达到对协方差矩阵进行Toeplitz矩阵重构的要求,通过协方差矩阵相乘来构造新的数据协方差矩阵。然后,通过Toeplitz矩阵重构来解相干。最后,利用旋转子空间算法准则构造聚焦矩阵,使用传播算子算法实现DOA估计。理论分析及仿真实验验证了该算法的有效性,该算法对相干信源数的奇偶没有限制,同时该算法也适用于高斯白噪声下宽带相干信号DOA估计的场景。 展开更多
关键词 波达方向估计 高斯色噪声 宽带相干信号 Toeplitz矩阵重构 传播算子算法
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基于场景理解的双波段彩色融合图像质量评价
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作者 高绍姝 田琪琳 +3 位作者 金伟其 伊升 倪潇 成昌龙 《北京理工大学学报》 EI CAS CSCD 北大核心 2023年第11期1205-1212,共8页
为了针对具体的视觉任务衡量可见光与红外彩色(夜视)融合图像的综合质量,提出了一种基于场景理解的双波段彩色融合图像综合质量客观评价模型.该模型包括融合图像特征提取器、邻域共生矩阵特征提取器和权重生成器三部分.首先,使用融合图... 为了针对具体的视觉任务衡量可见光与红外彩色(夜视)融合图像的综合质量,提出了一种基于场景理解的双波段彩色融合图像综合质量客观评价模型.该模型包括融合图像特征提取器、邻域共生矩阵特征提取器和权重生成器三部分.首先,使用融合图像特征提取器从融合图像中提取像素强度信息;然后,建立邻域共生矩阵特征提取器,从邻域共生矩阵中提取像素空间关系信息;最后,建立权重生成器,使用神经网络模型从梯度图中提取结构信息,将位置信息与结构信息相结合生成权重.实验结果表明,该方法在提取丰富的图像特征基础上,考虑人眼视觉特性,提高了模型预测值与人眼主观感受的一致程度,实现了融合图像综合质量的客观评价. 展开更多
关键词 图像质量评价 彩色融合图像 邻域共生矩阵 梯度图
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Development and validation of a postoperative pulmonary infection prediction model for patients with primary hepatic carcinoma 被引量:2
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作者 Chao Lu Zhi-Xiang Xing +4 位作者 Xi-Gang Xia Zhi-Da Long Bo Chen Peng Zhou Rui Wang 《World Journal of Gastrointestinal Oncology》 SCIE 2023年第7期1241-1252,共12页
BACKGROUND There are factors that significantly increase the risk of postoperative pulmonary infections in patients with primary hepatic carcinoma(PHC).Previous reports have shown that over 10%of patients with PHC exp... BACKGROUND There are factors that significantly increase the risk of postoperative pulmonary infections in patients with primary hepatic carcinoma(PHC).Previous reports have shown that over 10%of patients with PHC experience postoperative pulmonary infections.Thus,it is crucial to prioritize the prevention and treatment of postoperative pulmonary infections in patients with PHC.AIM To identify the risk factors for postoperative pulmonary infection in patients with PHC and develop a prediction model to aid in postoperative management.METHODS We retrospectively collected data from 505 patients who underwent hepatobiliary surgery between January 2015 and February 2023 in the Department of Hepatobiliary and Pancreaticospleen Surgery.Radiomics data were selected for statistical analysis,and clinical pathological parameters and imaging data were included in the screening database as candidate predictive variables.We then developed a pulmonary infection prediction model using three different models:An artificial neural network model;a random forest model;and a generalized linear regression model.Finally,we evaluated the accuracy and robustness of the prediction model using the receiver operating characteristic curve and decision curve analyses.RESULTS Among the 505 patients,86 developed a postoperative pulmonary infection,resulting in an incidence rate of 17.03%.Based on the gray-level co-occurrence matrix,we identified 14 categories of radiomic data for variable screening of pulmonary infection prediction models.Among these,energy,contrast,the sum of squares(SOS),the inverse difference(IND),mean sum(MES),sum variance(SUV),sum entropy(SUE),and entropy were independent risk factors for pulmonary infection after hepatectomy and were listed as candidate variables of machine learning prediction models.The random forest model algorithm,in combination with IND,SOS,MES,SUE,SUV,and entropy,demonstrated the highest prediction efficiency in both the training and internal verification sets,with areas under the curve of 0.823 and 0.801 and a 95%confidence interval of 0.766-0.880 and 0.744-0.858,respectively.The other two types of prediction models had prediction efficiencies between areas under the curve of 0.734 and 0.815 and 95%confidence intervals of 0.677-0.791 and 0.766-0.864,respectively.CONCLUSION Postoperative pulmonary infection in patients undergoing hepatectomy may be related to risk factors such as IND,SOS,MES,SUE,SUV,energy,and entropy.The prediction model in this study based on diffusion-weighted images,especially the random forest model algorithm,can better predict and estimate the risk of pulmonary infection in patients undergoing hepatectomy,providing valuable guidance for postoperative management. 展开更多
关键词 Primary hepatic carcinoma Pulmonary infection Gray-level co-occurrence matrix Machine learning PREDICTION
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基于视觉特性的图像质量评价 被引量:1
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作者 惠子薇 何坤 +1 位作者 冯犇 苏曜 《计算机工程》 CAS CSCD 北大核心 2023年第7期189-195,共7页
针对传统图像质量评价算法特征单一、全局和局部特征相关性不高的问题,从人眼视觉特性出发,结合图像全局与局部特征,提出一种基于视觉特性的图像质量评价算法。依据人眼视觉对亮度的响应和位置信息将图像划分为各个视觉区域,根据亮度和... 针对传统图像质量评价算法特征单一、全局和局部特征相关性不高的问题,从人眼视觉特性出发,结合图像全局与局部特征,提出一种基于视觉特性的图像质量评价算法。依据人眼视觉对亮度的响应和位置信息将图像划分为各个视觉区域,根据亮度和位置信息分割小区域,再利用颜色和位置信息对小区域进行合并以生成视觉仿生区域。利用区域内的颜色分布和区域之间的KL距离分别表示局部特征和全局特征,计算图像任意空间近邻区域颜色分布的KL距离以构建二元关系矩阵,即图像区域颜色相似性矩阵。在此基础上,对矩阵进行奇异值分解,提取矩阵的相似性信息,构造图像质量评价指标。在LIVE、CSIQ、TID2008这3个公开图像数据库上进行测试,结果表明,与PSNR、SSIM、BRISQUE、BIQI等算法相比,该算法的Pearson线性相关系数(PLCC)、Spearman等级相关系数(SROCC)、Kendall等级相关系数(KROCC)均取得了稳定且优异的结果,在LIVE和CSIQ数据库上的PLCC、SROCC和KROCC分别达到0.959 0、0.947 8、0.865 3和0.940 4、0.938 8、0.801 7,其评价结果与人眼主观质量评价结果具有高度的一致性,能够较好地评价图像质量。 展开更多
关键词 全局特征 局部特征 图像质量评价 KL距离 颜色相似性矩阵
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