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NeOR: neural exploration with feature-based visual odometry and tracking-failure-reduction policy 被引量:1
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作者 ZHU Ziheng LIU Jialing +2 位作者 CHEN Kaiqi TONG Qiyi LIU Ruyu 《Optoelectronics Letters》 2025年第5期290-297,共8页
Embodied visual exploration is critical for building intelligent visual agents. This paper presents the neural exploration with feature-based visual odometry and tracking-failure-reduction policy(Ne OR), a framework f... Embodied visual exploration is critical for building intelligent visual agents. This paper presents the neural exploration with feature-based visual odometry and tracking-failure-reduction policy(Ne OR), a framework for embodied visual exploration that possesses the efficient exploration capabilities of deep reinforcement learning(DRL)-based exploration policies and leverages feature-based visual odometry(VO) for more accurate mapping and positioning results. An improved local policy is also proposed to reduce tracking failures of feature-based VO in weakly textured scenes through a refined multi-discrete action space, keyframe fusion, and an auxiliary task. The experimental results demonstrate that Ne OR has better mapping and positioning accuracy compared to other entirely learning-based exploration frameworks and improves the robustness of feature-based VO by significantly reducing tracking failures in weakly textured scenes. 展开更多
关键词 intelligent visual agents deep reinforcement learning drl based embodied visual exploration feature based visual odometry tracking failure reduction policy neural exploration deep reinforcement learning
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Soft measurement for component content based on adaptive model of Pr/Nd color features 被引量:6
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作者 陆荣秀 杨辉 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2015年第12期1981-1986,共6页
For measurement of component content in the extraction and separation process of praseodymium/neodymium(Pr/Nd), a soft measurement method was proposed based on modeling of ion color features, which is suitable for fas... For measurement of component content in the extraction and separation process of praseodymium/neodymium(Pr/Nd), a soft measurement method was proposed based on modeling of ion color features, which is suitable for fast estimation of component content in production field. Feature analysis on images of the solution is conducted,which are captured from Pr/Nd extraction/separation field. H/S components in the HSI color space are selected as model inputs, so as to establish the least squares support vector machine(LSSVM) model for Nd(Pr) content,while the model parameters are determined with the GA algorithm. To improve the adaptability of the model,the adaptive iteration algorithm is used to correct parameters of the LSSVM model, on the basis of model correction strategy and new sample data. Using the field data collected from rare earth extraction production, predictive methods for component content and comparisons are given. The results indicate that the proposed method presents good adaptability and high prediction precision, so it is applicable to the fast detection of element content in the rare earth extraction. 展开更多
关键词 Pr/Nd extraction Color feature Component content Adaptive iterative least squares support vector machine Real-time correction
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New Approach on the Techniques of Content-Based Image Retrieval (CBIR) Using Color, Texture and Shape Features 被引量:3
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作者 Mohd Afizi Mohd Shukran Muhamad Naim Abdullah Mohd Sidek Fadhil Mohd Yunus 《Journal of Materials Science and Chemical Engineering》 2021年第1期51-57,共7页
<div style="text-align:justify;"> Digital image collection as rapidly increased along with the development of computer network. Image retrieval system was developed purposely to provide an efficient to... <div style="text-align:justify;"> Digital image collection as rapidly increased along with the development of computer network. Image retrieval system was developed purposely to provide an efficient tool for a set of images from a collection of images in the database that matches the user’s requirements in similarity evaluations such as image content similarity, edge, and color similarity. Retrieving images based on the content which is color, texture, and shape is called content based image retrieval (CBIR). The content is actually the feature of an image and these features are extracted and used as the basis for a similarity check between images. The algorithms used to calculate the similarity between extracted features. There are two kinds of content based image retrieval which are general image retrieval and application specific image retrieval. For the general image retrieval, the goal of the query is to obtain images with the same object as the query. Such CBIR imitates web search engines for images rather than for text. For application specific, the purpose tries to match a query image to a collection of images of a specific type such as fingerprints image and x-ray. In this paper, the general architecture, various functional components, and techniques of CBIR system are discussed. CBIR techniques discussed in this paper are categorized as CBIR using color, CBIR using texture, and CBIR using shape features. This paper also describe about the comparison study about color features, texture features, shape features, and combined features (hybrid techniques) in terms of several parameters. The parameters are precision, recall and response time. </div> 展开更多
关键词 content-based Image Retrieval Image Retrieval Information Retrieval
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Integrating Color and Spatial Feature for Content-Based Image Retrieval 被引量:1
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作者 Cao Kui Feng Yu-cai 《Wuhan University Journal of Natural Sciences》 EI CAS 2002年第3期290-296,共7页
In this paper, we present a novel and efficient scheme for extracting, indexing and retrieving color images. Our motivation was to reduce the space overhead of partition-based approaches taking advantage of the fact t... In this paper, we present a novel and efficient scheme for extracting, indexing and retrieving color images. Our motivation was to reduce the space overhead of partition-based approaches taking advantage of the fact that only a relatively low number of distinct values of a particular visual feature is present in most images. To extract color feature and build indices into our image database we take into consideration factors such as human color perception and perceptual range, and the image is partitioned into a set of regions by using a simple classifying scheme. The compact color feature vector and the spatial color histogram, which are extracted from the seqmented image region, are used for representing the color and spatial information in the image. We have also developed the region-based distance measures to compare the similarity of two images. Extensive tests on a large image collection were conducted to demonstrate the effectiveness of the proposed approach. 展开更多
关键词 color distribution spatial color histogram region-based image representation and retrieval similarity matching integrating of single features
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A FORMAL REPRESENTATION FOR FEATURE-BASED DESIGN 被引量:1
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作者 孙正兴 丁秋林 张福炎 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 1997年第1期37-46,共10页
Feature based design has been regarded as a promising approach for CAD/CAM integration.This paper aims to establish a domain independent representation formalism for feature based design in three aspects: formal re... Feature based design has been regarded as a promising approach for CAD/CAM integration.This paper aims to establish a domain independent representation formalism for feature based design in three aspects: formal representation,design process model and design algorithm.The implementing scheme and formal description of feature taxonomy,feature operator,feature model validation and feature transformation are given in the paper.The feature based design process model suited for either sequencial or concurrent engineering is proposed and its application to product structural design and process plan design is presented. Some general design algorithms for developing feature based design system are also addressed.The proposed scheme provides a formal methodology elementary for feature based design system development and operation in a structural way. 展开更多
关键词 CAD CAM product modelling design process feature based design representation formalism
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Content-based facial image authentication via statistic features
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作者 HAN Qi LI Qiong NIU Xia-mu 《通讯和计算机(中英文版)》 2009年第2期16-20,共5页
关键词 人脸图像 图像识别 计算机技术 图像处理
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Colour Features Extraction Techniques and Approaches for Content-Based Image Retrieval (CBIR) System
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作者 Muhammad Naim Abdullah Mohd Afizi Mohd Shukran +4 位作者 Mohd Rizal Mohd Isa Nor Suraya Mariam Ahmad Mohammad Adib Khairuddin Mohd Sidek Fadhil Mohd Yunus Fatimah Ahmad 《Journal of Materials Science and Chemical Engineering》 2021年第7期29-34,共6页
<div style="text-align:justify;"> An image retrieval system was developed purposely to provide an efficient tool for a set of images from a collection of images in the large database that matches the u... <div style="text-align:justify;"> An image retrieval system was developed purposely to provide an efficient tool for a set of images from a collection of images in the large database that matches the user’s requirements in similarity evaluations such as image content similarity, edge, and colour similarity. Retrieving images based on the contents which are colour, texture, and shape is called content-based image retrieval (CBIR). This paper discusses and describes about the colour features technique for image retrieval systems. Several colour features technique and algorithms produced by the previous researcher are used to calculate the similarity between extracted features. This paper also describes about the specific technique about the colour basis features and combined features (hybrid techniques) between colour and shape features. </div> 展开更多
关键词 content-based Image Retrieval Colour features CBIR
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Combining Block and Corner Features for Content-Based Trademark Retrieval
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作者 HONG Zhiling JIANG Qingshan WU Meihong 《Wuhan University Journal of Natural Sciences》 CAS 2007年第5期907-911,共5页
In order to retrieve a similarly look trademark from a large trademark database, an automatic content based trademark retrieval method using block hit statistic and comer Delaunay Triangulation features was proposed. ... In order to retrieve a similarly look trademark from a large trademark database, an automatic content based trademark retrieval method using block hit statistic and comer Delaunay Triangulation features was proposed. The block features are derived from the hit statistic on a series of concentric ellipse. The comers are detected based on an enhanced SUSAN (Smallest Univalue Segment Assimilating Nucleus) algorithm and the Delaunay Triangulation of comer points are used as the comer features. Experiments have been conducted on the MPEG-7 Core Experiment CE-Shape-1 database of 1 400 images and a trademark database of 2 000 images. The retrieval results are very encouraging. 展开更多
关键词 content-based image retrieval TRADEMARK concentric ellipse enhanced SUSAN
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Content-Based Lace Image Retrieval System Using a Hierarchical Multifeature Scheme
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作者 曹霞 李岳阳 +2 位作者 罗海驰 蒋高明 丛洪莲 《Journal of Donghua University(English Edition)》 EI CAS 2016年第4期562-565,568,共5页
An android-based lace image retrieval system based on content-based image retrieval (CBIR) technique is presented. This paper applies shape and texture features of lace image in our system and proposes a hierarchical ... An android-based lace image retrieval system based on content-based image retrieval (CBIR) technique is presented. This paper applies shape and texture features of lace image in our system and proposes a hierarchical multifeature scheme to facilitate coarseto-fine matching for efficient lace image retrieval in a large database. Experimental results demonstrate the feasibility and effectiveness of the proposed system meet the requirements of realtime. 展开更多
关键词 Retrieval retrieval matching hierarchical texture CBIR Hierarchical registration facilitate preprocessing
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A Feature-Based Parametric Product Modeling System in CIMS Environment 被引量:4
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作者 李海龙 《High Technology Letters》 EI CAS 1997年第1期13-16,共4页
This paper proposes an approach of developing the feature based parametric product modeling system which is suitable for integrated engineering design in CIMS environment.The architecture of ZD--MCADII and the charact... This paper proposes an approach of developing the feature based parametric product modeling system which is suitable for integrated engineering design in CIMS environment.The architecture of ZD--MCADII and the characteristics of its each module are introduced in detail. ZD--MCADII’s product data is managed by an object--oriented database management system OSCAR, and the product model is built according to the standard STEP. The product design is established on a unified product model, and all the product data are globally associated in ZD--MCADII. ZD--MCADII provides various design features to facilitate the product design, and supports the integrity of CAD, CAPP and CAM. 展开更多
关键词 CIMS feature based modeling PARAMETRIC design PRODUCT model OODB
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Evaluation of semivariogram features for objectbased image classification 被引量:2
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作者 Xian WU Jianwei PENG +1 位作者 Jie SHAN Weihong CUI 《Geo-Spatial Information Science》 SCIE EI CSCD 2015年第4期159-170,共12页
Inclusion of textures in image classification has been shown beneficial.This paper studies an efficient use of semivariogram features for object-based high-resolution image classification.First,an input image is divid... Inclusion of textures in image classification has been shown beneficial.This paper studies an efficient use of semivariogram features for object-based high-resolution image classification.First,an input image is divided into segments,for each of which a semivariogram is then calculated.Second,candidate features are extracted as a number of key locations of the semivariogram functions.Then we use an improved Relief algorithm and the principal component analysis to select independent and significant features.Then the selected prominent semivariogram features and the conventional spectral features are combined to constitute a feature vector for a support vector machine classifier.The effect of such selected semivariogram features is compared with those of the gray-level co-occurrence matrix(GLCM)features and window-based semivariogram texture features(STFs).Tests with aerial and satellite images show that such selected semivariogram features are of a more beneficial supplement to spectral features.The described method in this paper yields a higher classification accuracy than the combination of spectral and GLCM features or STFs. 展开更多
关键词 object based image analysis image segmentation image classification texture feature SEMIVARIOGRAM
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GENERATIVE CAPP APPROACH BASED ON RESOURCE MODEL AND FEATURE MODEL 被引量:1
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作者 倪前富 戴国洪 +1 位作者 严隽琪 马登哲 《Journal of Shanghai Jiaotong university(Science)》 EI 1998年第1期47-53,共7页
GENERATIVECAPPAPPROACHBASEDONRESOURCEMODELANDFEATUREMODEL*NiQianfu(倪前富)DaiGuohong(戴国洪)YanJunqi(严隽琪)MaDengzhe... GENERATIVECAPPAPPROACHBASEDONRESOURCEMODELANDFEATUREMODEL*NiQianfu(倪前富)DaiGuohong(戴国洪)YanJunqi(严隽琪)MaDengzhe(马登哲)(Dept.ofMech... 展开更多
关键词 严隽琪 ON RESOURCE based MODEL feature APPROACH AND
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Feature Selection for Image Classification Based on a New Ranking Criterion 被引量:1
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作者 Xuan Zhou Jiajun Wang 《Journal of Computer and Communications》 2015年第3期74-79,共6页
In this paper, a feature selection method combining the reliefF and SVM-RFE algorithm is proposed. This algorithm integrates the weight vector from the reliefF into SVM-RFE method. In this method, the reliefF filters ... In this paper, a feature selection method combining the reliefF and SVM-RFE algorithm is proposed. This algorithm integrates the weight vector from the reliefF into SVM-RFE method. In this method, the reliefF filters out many noisy features in the first stage. Then the new ranking criterion based on SVM-RFE method is applied to obtain the final feature subset. The SVM classifier is used to evaluate the final image classification accuracy. Experimental results show that our proposed relief- SVM-RFE algorithm can achieve significant improvements for feature selection in image classification. 展开更多
关键词 feature SELECTION for IMAGE Classification based on a New RANKING CRITERION
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Image block feature vectors based on a singular-value information metric and color-texture description 被引量:4
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作者 王朔中 路兴 +1 位作者 苏胜君 张新鹏 《Journal of Shanghai University(English Edition)》 CAS 2007年第3期205-209,共5页
In this work, image feature vectors are formed for blocks containing sufficient information, which are selected using a singular-value criterion. When the ratio between the first two SVs axe below a given threshold, t... In this work, image feature vectors are formed for blocks containing sufficient information, which are selected using a singular-value criterion. When the ratio between the first two SVs axe below a given threshold, the block is considered informative. A total of 12 features including statistics of brightness, color components and texture measures are used to form intermediate vectors. Principal component analysis is then performed to reduce the dimension to 6 to give the final feature vectors. Relevance of the constructed feature vectors is demonstrated by experiments in which k-means clustering is used to group the vectors hence the blocks. Blocks falling into the same group show similar visual appearances. 展开更多
关键词 image feature COLOR TEXTURE content-based image retrieval (CBIR) image hashing
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DIMENSION VARIATION OF FEATURE-BASED MODEL BY OPERATING DIRECTLY ON B-REP
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作者 何小朝 王宗彦 +1 位作者 彭维 张铁昌 《Chinese Journal of Aeronautics》 SCIE EI CSCD 1998年第2期57-63,共7页
DIMENSIONVARIATIONOFFEATURE┐BASEDMODELBYOPERATINGDIRECTLYONB┐REPHEXiaozhao(何小朝),WANGZongyan(王宗彦)PENGWei(彭维),... DIMENSIONVARIATIONOFFEATURE┐BASEDMODELBYOPERATINGDIRECTLYONB┐REPHEXiaozhao(何小朝),WANGZongyan(王宗彦)PENGWei(彭维),ZHANGTiechang(张铁昌... 展开更多
关键词 design by feature CONSTRAINT feature based model dimension variation
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MFSR: Maximum Feature Score Region-based Captions Locating in News Video Images
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作者 Zhi-Heng Wang Chao Guo +1 位作者 Hong-Min Liu Zhan-Qiang Huo 《International Journal of Automation and computing》 EI CSCD 2018年第4期454-461,共8页
For news video images, caption recognizing is a useful and important step for content understanding. Caption locating is usually the first step of caption recognizing and this paper proposes a simple but effective cap... For news video images, caption recognizing is a useful and important step for content understanding. Caption locating is usually the first step of caption recognizing and this paper proposes a simple but effective caption locating algorithm called maximum feature score region (MFSR) based method, which mainly consists of two stages: In the first stage, up/down boundaries are attained by turning to edge map projection. Then, maximum feature score region is defined and left/right boundaries are achieved by utilizing MFSR. Experiments show that the proposed MFSR based method has superior and robust performance on news video images of different types. 展开更多
关键词 News video images captions recognizing captions locating content understanding maximum feature score region(MFSR).
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Fast Image Retrieval of Textile Industrial Accessory Based on Multi-Feature Fusion
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作者 沈文忠 杨杰 《Journal of Donghua University(English Edition)》 EI CAS 2004年第3期117-122,共6页
A hierarchical retrieval scheme of the accessory image database is proposed based on textile industrial accessory contour feature and region feature. At first smallest enclosed rectangle[1] feature (degree of accessor... A hierarchical retrieval scheme of the accessory image database is proposed based on textile industrial accessory contour feature and region feature. At first smallest enclosed rectangle[1] feature (degree of accessory coordination) is used to filter the image database to decouple the image search scope. After the accessory contour information and region information are extracted, the fusion multi-feature of the centroid distance Fourier descriptor and distance distribution histogram is adopted to finish image retrieval accurately. All the features above are invariable under translation, scaling and rotation. Results from the test on the image database including 1,000 accessory images demonstrate that the method is effective and practical with high accuracy and fast speed. 展开更多
关键词 content based retrieval smallest enclosed rectangle (SER) hierarchical retrieval Fourier descriptor feature fusion
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Feature-based and objectoriented product information model for welding structure
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作者 林三宝 杨春利 +1 位作者 黎明 吴林 《China Welding》 EI CAS 1999年第2期3-10,共8页
Product information model for welding structure plays an important role for the integration of welding CAD/CAPP/CAM. However, existing CAD modeling systems are not capable of providing enough information for subsequen... Product information model for welding structure plays an important role for the integration of welding CAD/CAPP/CAM. However, existing CAD modeling systems are not capable of providing enough information for subsequent manufacturing activities such as CAPP and CAM. A new design approach using feature technique and object oriented programming method is put forward in this paper in order to create the product information model of welding structure. With this approach, the product information model is able to effectively support computer aided welding process planning, fixturing, assembling, path planning of welding robot and other manufacturing activities. The feature classification and representing scheme of welding structure are discussed. A prototype system is developed based on feature and object oriented programming. Its structure and functions are given in detail. 展开更多
关键词 object oriented programming feature based design product information model welding structure CAD/CAM integration
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Hepatic CT Image Query Based on Threshold-based Classification Scheme with Gabor Features
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作者 蒋历军 罗永兴 +1 位作者 赵俊 庄天戈 《Journal of Shanghai Jiaotong university(Science)》 EI 2008年第6期753-758,共6页
Hepatic computed tomography(CT) images with Gabor function were analyzed.Then a threshold-based classification scheme was proposed using Gabor features and proceeded with the retrieval of the hepatic CT images.In our ... Hepatic computed tomography(CT) images with Gabor function were analyzed.Then a threshold-based classification scheme was proposed using Gabor features and proceeded with the retrieval of the hepatic CT images.In our experiments, a batch of hepatic CT images containing several types of CT findings was used and compared with the Zhao's image classification scheme, support vector machines(SVM) scheme and threshold-based scheme. 展开更多
关键词 content based image retrieval Gabor features threshold-based scheme support vector machines (SVM) hepatic computed tomography (CT) images
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Feature-Based Aggregation and Deep Reinforcement Learning:A Survey and Some New Implementations 被引量:15
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作者 Dimitri P.Bertsekas 《IEEE/CAA Journal of Automatica Sinica》 EI CSCD 2019年第1期1-31,共31页
In this paper we discuss policy iteration methods for approximate solution of a finite-state discounted Markov decision problem, with a focus on feature-based aggregation methods and their connection with deep reinfor... In this paper we discuss policy iteration methods for approximate solution of a finite-state discounted Markov decision problem, with a focus on feature-based aggregation methods and their connection with deep reinforcement learning schemes. We introduce features of the states of the original problem, and we formulate a smaller "aggregate" Markov decision problem, whose states relate to the features. We discuss properties and possible implementations of this type of aggregation, including a new approach to approximate policy iteration. In this approach the policy improvement operation combines feature-based aggregation with feature construction using deep neural networks or other calculations. We argue that the cost function of a policy may be approximated much more accurately by the nonlinear function of the features provided by aggregation, than by the linear function of the features provided by neural networkbased reinforcement learning, thereby potentially leading to more effective policy improvement. 展开更多
关键词 REINFORCEMENT learning dynamic programming Markovian DECISION problems AGGREGATION feature-based ARCHITECTURES policy ITERATION DEEP neural networks rollout algorithms
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