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Recommendation Algorithm Integrating CNN and Attention System in Data Extraction 被引量:1
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作者 Yang Li Fei Yin Xianghui Hui 《Computers, Materials & Continua》 SCIE EI 2023年第5期4047-4063,共17页
With the rapid development of the Internet globally since the 21st century,the amount of data information has increased exponentially.Data helps improve people’s livelihood and working conditions,as well as learning ... With the rapid development of the Internet globally since the 21st century,the amount of data information has increased exponentially.Data helps improve people’s livelihood and working conditions,as well as learning efficiency.Therefore,data extraction,analysis,and processing have become a hot issue for people from all walks of life.Traditional recommendation algorithm still has some problems,such as inaccuracy,less diversity,and low performance.To solve these problems and improve the accuracy and variety of the recommendation algorithms,the research combines the convolutional neural networks(CNN)and the attention model to design a recommendation algorithm based on the neural network framework.Through the text convolutional network,the input layer in CNN has transformed into two channels:static ones and non-static ones.Meanwhile,the self-attention system focuses on the system so that data can be better processed and the accuracy of feature extraction becomes higher.The recommendation algorithm combines CNN and attention system and divides the embedding layer into user information feature embedding and data name feature extraction embedding.It obtains data name features through a convolution kernel.Finally,the top pooling layer obtains the length vector.The attention system layer obtains the characteristics of the data type.Experimental results show that the proposed recommendation algorithm that combines CNN and the attention system can perform better in data extraction than the traditional CNN algorithm and other recommendation algorithms that are popular at the present stage.The proposed algorithm shows excellent accuracy and robustness. 展开更多
关键词 Data extraction recommendation algorithm CNN algorithm attention model
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Background dominant colors extraction method based on color image quick fuzzy c-means clustering algorithm 被引量:2
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作者 Zun-yang Liu Feng Ding +1 位作者 Ying Xu Xu Han 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2021年第5期1782-1790,共9页
A quick and accurate extraction of dominant colors of background images is the basis of adaptive camouflage design.This paper proposes a Color Image Quick Fuzzy C-Means(CIQFCM)clustering algorithm based on clustering ... A quick and accurate extraction of dominant colors of background images is the basis of adaptive camouflage design.This paper proposes a Color Image Quick Fuzzy C-Means(CIQFCM)clustering algorithm based on clustering spatial mapping.First,the clustering sample space was mapped from the image pixels to the quantized color space,and several methods were adopted to compress the amount of clustering samples.Then,an improved pedigree clustering algorithm was applied to obtain the initial class centers.Finally,CIQFCM clustering algorithm was used for quick extraction of dominant colors of background image.After theoretical analysis of the effect and efficiency of the CIQFCM algorithm,several experiments were carried out to discuss the selection of proper quantization intervals and to verify the effect and efficiency of the CIQFCM algorithm.The results indicated that the value of quantization intervals should be set to 4,and the proposed algorithm could improve the clustering efficiency while maintaining the clustering effect.In addition,as the image size increased from 128×128 to 1024×1024,the efficiency improvement of CIQFCM algorithm was increased from 6.44 times to 36.42 times,which demonstrated the significant advantage of CIQFCM algorithm in dominant colors extraction of large-size images. 展开更多
关键词 Dominant colors extraction Quick clustering algorithm Clustering spatial mapping Background image Camouflage design
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A real-time intelligent lithology identification method based on a dynamic felling strategy weighted random forest algorithm
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作者 Tie Yan Rui Xu +2 位作者 Shi-Hui Sun Zhao-Kai Hou Jin-Yu Feng 《Petroleum Science》 SCIE EI CAS CSCD 2024年第2期1135-1148,共14页
Real-time intelligent lithology identification while drilling is vital to realizing downhole closed-loop drilling. The complex and changeable geological environment in the drilling makes lithology identification face ... Real-time intelligent lithology identification while drilling is vital to realizing downhole closed-loop drilling. The complex and changeable geological environment in the drilling makes lithology identification face many challenges. This paper studies the problems of difficult feature information extraction,low precision of thin-layer identification and limited applicability of the model in intelligent lithologic identification. The author tries to improve the comprehensive performance of the lithology identification model from three aspects: data feature extraction, class balance, and model design. A new real-time intelligent lithology identification model of dynamic felling strategy weighted random forest algorithm(DFW-RF) is proposed. According to the feature selection results, gamma ray and 2 MHz phase resistivity are the logging while drilling(LWD) parameters that significantly influence lithology identification. The comprehensive performance of the DFW-RF lithology identification model has been verified in the application of 3 wells in different areas. By comparing the prediction results of five typical lithology identification algorithms, the DFW-RF model has a higher lithology identification accuracy rate and F1 score. This model improves the identification accuracy of thin-layer lithology and is effective and feasible in different geological environments. The DFW-RF model plays a truly efficient role in the realtime intelligent identification of lithologic information in closed-loop drilling and has greater applicability, which is worthy of being widely used in logging interpretation. 展开更多
关键词 Intelligent drilling Closed-loop drilling Lithology identification Random forest algorithm Feature extraction
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Calculation of Extraction Equilibrium in Multi-Component System by Newton-Raphson Algorithm
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作者 贾江涛 王建方 +3 位作者 严纯华 廖春生 吴声 李标国 《Journal of Rare Earths》 SCIE EI CAS CSCD 1999年第4期246-249,共4页
Based on the extraction equilibrium and mass balances in countercurrent extraction systems, a novel method was studied for dealing with the extraction equilibrium and the mass distribution in a multi-component(gamma-c... Based on the extraction equilibrium and mass balances in countercurrent extraction systems, a novel method was studied for dealing with the extraction equilibrium and the mass distribution in a multi-component(gamma-component) system. The relationships of mass distribution (x(i), y(i), i = 1, ..., lambda) between two phases were expressed by 2 lambda dimensional simultaneous equations. These simultaneous equations can be converted to a one-dimension nonlinear equation, then it was solved by Newton-Raphson algorithm within a few number of iteration. Compared with the regular calculation method for the 2 lambda dimensional simultaneous equations, Newton-Raphson algorithm can decrease the number of iteration, increase the convergence of the equations and accelerate the speed of simulation. It was verified in many multi-component systems with satisfactory results. As an example, a five-component system is demonstrated in this paper. 展开更多
关键词 rare earths multi-component system extraction equilibrium Newton-Raphson algorithm
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On Liu Yi’s Positive-Negative Root Extraction Algorithm
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《Wuhan University Journal of Natural Sciences》 CAS 1997年第1期3-10,共8页
OnLiuYi’sPositive┐NegativeRootExtractionAlgorithmWangRongbinDepartmentofMathematics,WuhanUniversity,Wuhan430... OnLiuYi’sPositive┐NegativeRootExtractionAlgorithmWangRongbinDepartmentofMathematics,WuhanUniversity,Wuhan430072,ChinaAbstrac... 展开更多
关键词 ROOT extraction LIU On algorithm YI 秦九韶 演段 释锁 朱世杰
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A Haze Feature Extraction and Pollution Level Identification Pre-Warning Algorithm
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作者 Yongmei Zhang Jianzhe Ma +3 位作者 Lei Hu Keming Yu Lihua Song Huini Chen 《Computers, Materials & Continua》 SCIE EI 2020年第9期1929-1944,共16页
The prediction of particles less than 2.5 micrometers in diameter(PM2.5)in fog and haze has been paid more and more attention,but the prediction accuracy of the results is not ideal.Haze prediction algorithms based on... The prediction of particles less than 2.5 micrometers in diameter(PM2.5)in fog and haze has been paid more and more attention,but the prediction accuracy of the results is not ideal.Haze prediction algorithms based on traditional numerical and statistical prediction have poor effects on nonlinear data prediction of haze.In order to improve the effects of prediction,this paper proposes a haze feature extraction and pollution level identification pre-warning algorithm based on feature selection and integrated learning.Minimum Redundancy Maximum Relevance method is used to extract low-level features of haze,and deep confidence network is utilized to extract high-level features.eXtreme Gradient Boosting algorithm is adopted to fuse low-level and high-level features,as well as predict haze.Establish PM2.5 concentration pollution grade classification index,and grade the forecast data.The expert experience knowledge is utilized to assist the optimization of the pre-warning results.The experiment results show the presented algorithm can get better prediction effects than the results of Support Vector Machine(SVM)and Back Propagation(BP)widely used at present,the accuracy has greatly improved compared with SVM and BP. 展开更多
关键词 Deep belief networks feature extraction PM2.5 eXtreme gradient boosting algorithm haze pollution
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A Fast Algorithm of Dynamic Background Extraction 被引量:1
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作者 Yong Fan Zhengyu Zhang 《通讯和计算机(中英文版)》 2006年第7期74-77,共4页
关键词 图像处理 多样化运算 运算方法 背景处理
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Coupled Cross-correlation Neural Network Algorithm for Principal Singular Triplet Extraction of a Cross-covariance Matrix 被引量:2
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作者 Xiaowei Feng Xiangyu Kong Hongguang Ma 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI 2016年第2期149-156,共8页
This paper proposes a novel coupled neural network learning algorithm to extract the principal singular triplet(PST)of a cross-correlation matrix between two high-dimensional data streams. We firstly introduce a novel... This paper proposes a novel coupled neural network learning algorithm to extract the principal singular triplet(PST)of a cross-correlation matrix between two high-dimensional data streams. We firstly introduce a novel information criterion(NIC),in which the stationary points are singular triplet of the crosscorrelation matrix. Then, based on Newton's method, we obtain a coupled system of ordinary differential equations(ODEs) from the NIC. The ODEs have the same equilibria as the gradient of NIC, however, only the first PST of the system is stable(which is also the desired solution), and all others are(unstable)saddle points. Based on the system, we finally obtain a fast and stable algorithm for PST extraction. The proposed algorithm can solve the speed-stability problem that plagues most noncoupled learning rules. Moreover, the proposed algorithm can also be used to extract multiple PSTs effectively by using sequential method. 展开更多
关键词 Singular value decomposition(SVD) coupled algorithm cross-correlation neural network(CNN) speed-stability problem principal singular subspace(PSS) principal singular triplet(PST)
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Key Frames Extraction Based on the Improved Genetic Algorithm
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作者 ZHOU Dong-sheng JIANG Wei +1 位作者 YI Peng-fei LIU Rui 《Computer Aided Drafting,Design and Manufacturing》 2014年第4期74-78,共5页
In order toovercomethe poor local search ability of genetic algorithm, resulting in the basic genetic algorithm is time-consuming, and low search abilityin the late evolutionary, we use thegray coding instead ofbinary... In order toovercomethe poor local search ability of genetic algorithm, resulting in the basic genetic algorithm is time-consuming, and low search abilityin the late evolutionary, we use thegray coding instead ofbinary codingatthebeginning of the coding;we use multi-point crossoverto replace the originalsingle-point crossoveroperation.Finally, theexperimentshows that the improved genetic algorithmnot only has a strong search capability, but also thestability has been effectively improved. 展开更多
关键词 key frames extraction grey code binary code genetic algorithm
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The extraction and smoothing algorithms for γ-ray spectrum of a CdZnTe detector system
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作者 许鹏 王宋 +2 位作者 蔡星会 李如松 霍勇刚 《Nuclear Science and Techniques》 SCIE CAS CSCD 2014年第5期53-56,共4页
The extraction algorithms for pulse amplitude and smoothing of energy spectrum have a great influence on energy spectrum of γ-rays during the digital detection and analysis procedure. For a CdZnTe digital γ detector... The extraction algorithms for pulse amplitude and smoothing of energy spectrum have a great influence on energy spectrum of γ-rays during the digital detection and analysis procedure. For a CdZnTe digital γ detector system, different extraction algorithms for pulse amplitude and smoothing of energy spectrum are discussed in this paper. The results show that extraction of pulse amplitude using the first-order derivative method and smoothing of energy spectrum using the wavelet transformation method may obtain energy spectrum with good performance. 展开更多
关键词 探测器系统 提取算法 平滑算法 碲锌镉 γ射线谱 γ射线能谱 小波变换方法 脉冲幅度
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Road network extraction in classified SAR images using genetic algorithm
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作者 肖志强 鲍光淑 蒋晓确 《Journal of Central South University of Technology》 2004年第2期180-184,共5页
Due to the complicated background of objectives and speckle noise, it is almost impossible to extract roads directly from original synthetic aperture radar(SAR) images. A method is proposed for extraction of road netw... Due to the complicated background of objectives and speckle noise, it is almost impossible to extract roads directly from original synthetic aperture radar(SAR) images. A method is proposed for extraction of road network from high-resolution SAR image. Firstly, fuzzy C means is used to classify the filtered SAR image unsupervisedly, and the road pixels are isolated from the image to simplify the extraction of road network. Secondly, according to the features of roads and the membership of pixels to roads, a road model is constructed, which can reduce the extraction of road network to searching globally optimization continuous curves which pass some seed points. Finally, regarding the curves as individuals and coding a chromosome using integer code of variance relative to coordinates, the genetic operations are used to search global optimization roads. The experimental results show that the algorithm can effectively extract road network from high-resolution SAR images. 展开更多
关键词 遗传运算法则 路网萃取 安全分析报告 孔径雷达 图象处理
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Improved method for the feature extraction of laser scanner using genetic clustering 被引量:6
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作者 Yu Jinxia Cai Zixing Duan Zhuohua 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2008年第2期280-285,共6页
Feature extraction of range images provided by ranging sensor is a key issue of pattern recognition. To automatically extract the environmental feature sensed by a 2D ranging sensor laser scanner, an improved method b... Feature extraction of range images provided by ranging sensor is a key issue of pattern recognition. To automatically extract the environmental feature sensed by a 2D ranging sensor laser scanner, an improved method based on genetic clustering VGA-clustering is presented. By integrating the spatial neighbouring information of range data into fuzzy clustering algorithm, a weighted fuzzy clustering algorithm (WFCA) instead of standard clustering algorithm is introduced to realize feature extraction of laser scanner. Aimed at the unknown clustering number in advance, several validation index functions are used to estimate the validity of different clustering algorithms and one validation index is selected as the fitness function of genetic algorithm so as to determine the accurate clustering number automatically. At the same time, an improved genetic algorithm IVGA on the basis of VGA is proposed to solve the local optimum of clustering algorithm, which is implemented by increasing the population diversity and improving the genetic operators of elitist rule to enhance the local search capacity and to quicken the convergence speed. By the comparison with other algorithms, the effectiveness of the algorithm introduced is demonstrated. 展开更多
关键词 laser scanner feature extraction weighted fuzzy clustering validation index genetic algorithm.
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Experimental optimization and mathematical modeling of supercritical carbon dioxide extraction of essential oil from Pogostemon cablin 被引量:3
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作者 Kangning Xiong Yun Chen Shuai Shen 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2019年第10期2407-2417,共11页
The supercritical carbon dioxide extraction was applied to obtain essential oil from Pogostemon cablin in this work.Effect of extraction parameters including temperature,pressure,extraction time and particle size on e... The supercritical carbon dioxide extraction was applied to obtain essential oil from Pogostemon cablin in this work.Effect of extraction parameters including temperature,pressure,extraction time and particle size on extraction yield was investigated,and the response surface methodology with a Box–Behnken Design was used to achieve the optimized extraction conditions.The maximum yield of essential oil was 2.4356%under the conditions of extraction temperature 47°C,pressure 24.5 MPa and extraction time 119 min.Moreover,based on the Brunauer–Emmett–Teller theory of adsorption,a mathematical modeling was performed to correlate the measured data.The model shows a function relationship between extraction yield and time by a simple equation with three significantly adjustable parameters.These model parameters have been optimized through simulated annealing algorithm.The predicted data from the mathematical model show a good agreement with the experimental data of the different extraction parameters. 展开更多
关键词 SUPERCRITICAL CARBON dioxide extraction Pogostemon cablin Response surface METHODOLOGY MATHEMATICAL modeling SIMULATED ANNEALING algorithm
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Component Content Soft-Sensor Based on Hybrid Models in Countercurrent Rare Earth Extraction Process 被引量:3
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作者 杨辉 王欣 《Journal of Rare Earths》 SCIE EI CAS CSCD 2005年第S1期86-91,共6页
In consideration of the online measurement of the component content in rare earth countercurrent extraction separation process, the soft sensor method based on hybrid modeling was proposed to measure the rare earth co... In consideration of the online measurement of the component content in rare earth countercurrent extraction separation process, the soft sensor method based on hybrid modeling was proposed to measure the rare earth component content. The hybrid models were composed of the extraction equilibrium calculation model and the Radial Basis Function (RBF) Neural Network (NN) error compensation model; the parameters of compensation model were optimized by the hierarchical genetic algorithms (HGA). In addition, application experiment research of this proposed method was carried out in the rare earth separation production process of a corporation. The result shows that this method is effective and can realize online measurement for the component content of rare earth in the countercurrent extraction. 展开更多
关键词 countercurrent extraction soft-sensor equilibrium calculation model RBF neural networks hierarchical genetic algorithms rare earths
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Application of a new feature extraction and optimization method to surface defect recognition of cold rolled strips 被引量:5
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作者 Guifang Wu Ke Xu Jinwu Xu 《Journal of University of Science and Technology Beijing》 CSCD 2007年第5期437-442,共6页
Considering that the surface defects of cold rolled strips are hard to be recognized by human eyes under high-speed circumstances, an automatic recognition technique was discussed. Spectrum images of defects can be go... Considering that the surface defects of cold rolled strips are hard to be recognized by human eyes under high-speed circumstances, an automatic recognition technique was discussed. Spectrum images of defects can be got by fast Fourier transform (FFF) and sum of valid pixels (SVP), and its optimized center region, which concentrates nearly all energies, are extracted as an original feature set. Using genetic algorithm to optimize the feature set, an optimized feature set with 51 features can be achieved. Using the optimized feature set as an input vector of neural networks, the recognition effects of LVQ neural networks have been studied. Experiment results show that the new method can get a higher classification rate and can settle the automatic recognition problem of surface defects on cold rolled strips ideally. 展开更多
关键词 cold rolled strip surface defect neural networks fast Fourier transform (FFT) feature extraction and optimization genetic algorithm feature set
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Automatic Extraction of Urban Road Centerlines from High-Resolution Satellite Imagery Using Automatic Thresholding and Morphological Operation Method 被引量:6
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作者 Abdur Raziq Aigong Xu Yu Li 《Journal of Geographic Information System》 2016年第4期517-525,共9页
The commercial high-resolution imaging satellite with 1 m spatial resolution IKONOS is an important data source of information for urban planning and geographical information system (GIS) applications. In this paper, ... The commercial high-resolution imaging satellite with 1 m spatial resolution IKONOS is an important data source of information for urban planning and geographical information system (GIS) applications. In this paper, a morphological method is proposed. The proposed method combines the automatic thresholding and morphological operation techniques to extract the road centerline of the urban environment. This method intends to solve urban road centerline problems, vehicle, vegetation, building etc. Based on this morphological method, an object extractor is designed to extract road networks from highly remote sensing images. Some filters are applied in this experiment such as line reconstruction and region filling techniques to connect the disconnected road segments and remove the small redundant. Finally, the thinning algorithm is used to extract the road centerline. Experiments have been conducted on a high-resolution IKONOS and QuickBird images showing the efficiency of the proposed method. 展开更多
关键词 Automatic Thresholding High-Resolution Imagery Morphological Operation Posts Processing Thinning algorithm Urban Road Centerlines extraction
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Feature Extraction to Polar Image 被引量:1
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作者 Donghua Gu Zhenyu Han Qinge Wu 《Journal of Computer and Communications》 2017年第11期16-26,共11页
Some algorithms of feature extraction in existing literature studied for image processing was the gray image with one-dimensional parameter. However, some feature points’ extraction for three-dimensional color of pol... Some algorithms of feature extraction in existing literature studied for image processing was the gray image with one-dimensional parameter. However, some feature points’ extraction for three-dimensional color of polar image, such as the color edge extraction, inflection points, and so on, was urgently to be solved a polar color problem. For achieving quickly and accurately the color feature extraction to polar image, this paper proposed a similar region of color algorithm. The algorithm was compared to polar image, and the effect to color extraction was also described by the combination of the proposed and existing algorithms. Moreover, this paper gave the comparison of the proposed algorithm and an existing classical algorithm to extraction of color feature. These researches in this paper provided a powerful tool for polar image classification, color feature segmentation, precise recognition, and so on. 展开更多
关键词 Similar Region of COLOR algorithm POLAR IMAGE EDGE Detection CORNER Point extraction
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Apriori and N-gram Based Chinese Text Feature Extraction Method 被引量:4
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作者 王晔 黄上腾 《Journal of Shanghai Jiaotong university(Science)》 EI 2004年第4期11-14,20,共5页
A feature extraction, which means extracting the representative words from a text, is an important issue in text mining field. This paper presented a new Apriori and N-gram based Chinese text feature extraction method... A feature extraction, which means extracting the representative words from a text, is an important issue in text mining field. This paper presented a new Apriori and N-gram based Chinese text feature extraction method, and analyzed its correctness and performance. Our method solves the question that the exist extraction methods cannot find the frequent words with arbitrary length in Chinese texts. The experimental results show this method is feasible. 展开更多
关键词 演绎算法 汉语分割 特征提取 中文文本
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改进的Brain Extraction Tool算法及其在脑实质分割中的应用
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作者 王晓飞 聂生东 王远军 《中国医学物理学杂志》 CSCD 2016年第2期113-117,共5页
BET(Brain Extraction Tool)算法是一种常用的从磁共振(MRI)脑图像中分割脑实质的工具,在实际应用中发现,BET算法对正常脑实质的分割精度较高,但对有病灶的脑实质分割精度较差。根据BET算法存在的问题,改进原BET算法中不合理的u_3,简化... BET(Brain Extraction Tool)算法是一种常用的从磁共振(MRI)脑图像中分割脑实质的工具,在实际应用中发现,BET算法对正常脑实质的分割精度较高,但对有病灶的脑实质分割精度较差。根据BET算法存在的问题,改进原BET算法中不合理的u_3,简化了计算繁琐的u_2,并将其应用于分割MRI图像中的脑实质。首先:选择序列图像中间层,对其应用两次改进后的BET算法获得精确分割结果;然后:将获得的边界向其中心缩小一定比例后作为与其相邻层的初始边界再次应用修改后的算法获得该层精确边界;最后,不断重复上述步骤直至所有层分割结束。改进后的算法对脑部图像分割结果与人工分割结果的重叠率达到92.92%,而使用FSL中提供的BET工具的分割结果与人工分割结果的重叠率为88.94%。改进后的算法相比原BET算法能够更加准确地分割MRI图像中的脑实质。 展开更多
关键词 BET算法 磁共振图像 脑实质 分割
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Text Extraction and Enhancement of Binary Images Using Cellular Automata
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作者 G. Sahoo Tapas Kumar +1 位作者 B. L. Raina C. M. Bhatia 《International Journal of Automation and computing》 EI 2009年第3期254-260,共7页
Text characters embedded in images represent a rich source of information for content-based indexing and retrieval applications. However, these text characters are difficult to be detected and recognized due to their ... Text characters embedded in images represent a rich source of information for content-based indexing and retrieval applications. However, these text characters are difficult to be detected and recognized due to their various sizes, grayscale values, and complex backgrounds. Existing methods cannot handle well those texts with different contrast or embedded in a complex image background. In this paper, a set of sequential algorithms for text extraction and enhancement of image using cellular automata are proposed. The image enhancement includes gray level, contrast manipulation, edge detection, and filtering. First, it applies edge detection and uses a threshold to filter out for low-contrast text and simplify complex background of high-contrast text from binary image. The proposed algorithm is simple and easy to use and requires only a sample texture binary image as an input. It generates textures with perceived quality, better than those proposed by earlier published techniques. The performance of our method is demonstrated by presenting experimental results for a set of text based binary images. The quality of thresholding is assessed using the precision and recall analysis of the resultant text in the binary image. 展开更多
关键词 Text extraction edge detection cellular automata algorithm text detection thresholding.
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