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A new similarity computing method based on concept similarity in Chinese text processing 被引量:4
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作者 PENG Jing YANG DongQing +2 位作者 TANG ShiWei WANG TengJiao GAO Jun 《Science in China(Series F)》 2008年第9期1215-1230,共16页
The paper proposes a new text similarity computing method based on concept similarity in Chinese text processing. The new method converts text to words vector space model at first, and then splits words into a set of ... The paper proposes a new text similarity computing method based on concept similarity in Chinese text processing. The new method converts text to words vector space model at first, and then splits words into a set of concepts. Through computing the inner products between concepts, it obtains the similarity between words. The new method computes the similarity of text based on the similarity of words at last. The contributions of the paper include: 1) propose a new computing formula between words; 2) propose a new text similarity computing method based on words similarity; 3) successfully use the method in the application of similarity computing of WEB news; and 4) prove the validity of the method through extensive experiments. 展开更多
关键词 concept similarity similarity computing vector space inner product space
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A Synergistic Multi-Attribute Decision-Making Method for Educational Institutions Evaluation Using Similarity Measures of Possibility Pythagorean Fuzzy Hypersoft Sets
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作者 Khuram Ali Khan Saba Mubeen Ishfaq +1 位作者 Atiqe Ur Rahman Salwa El-Morsy 《Computer Modeling in Engineering & Sciences》 SCIE EI 2025年第1期501-530,共30页
Due to the numerous variables to take into account as well as the inherent ambiguity and uncertainty,evaluating educational institutions can be difficult.The concept of a possibility Pythagorean fuzzy hypersoft set(pP... Due to the numerous variables to take into account as well as the inherent ambiguity and uncertainty,evaluating educational institutions can be difficult.The concept of a possibility Pythagorean fuzzy hypersoft set(pPyFHSS)is more flexible in this regard than other theoretical fuzzy set-like models,even though some attempts have been made in the literature to address such uncertainties.This study investigates the elementary notions of pPyFHSS including its set-theoretic operations union,intersection,complement,OR-and AND-operations.Some results related to these operations are also modified for pPyFHSS.Additionally,the similarity measures between pPyFHSSs are formulated with the assistance of numerical examples and results.Lastly,an intelligent decision-assisted mechanism is developed with the proposal of a robust algorithm based on similarity measures for solving multi-attribute decision-making(MADM)problems.A case study that helps the decision-makers assess the best educational institution is discussed to validate the suggested system.The algorithmic results are compared with the most pertinent model to evaluate the adaptability of pPyFHSS,as it generalizes the classical possibility fuzzy set-like theoretical models.Similarly,while considering significant evaluating factors,the flexibility of pPyFHSS is observed through structural comparison. 展开更多
关键词 Hypersoft set Pythagorean fuzzy hypersoft set computational complexity multi-attribute decision-making optimization similarity measures uncertainty
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In an Ocean or a River:Bilinear Auto-Backlund Transformations and Similarity Reductions on an Extended Time-Dependent(3+1)-Dimensional Shallow Water Wave Equation 被引量:1
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作者 GAO Xin-yi 《China Ocean Engineering》 2025年第1期160-165,共6页
With respect to oceanic fluid dynamics,certain models have appeared,e.g.,an extended time-dependent(3+1)-dimensional shallow water wave equation in an ocean or a river,which we investigate in this paper.Using symbolic... With respect to oceanic fluid dynamics,certain models have appeared,e.g.,an extended time-dependent(3+1)-dimensional shallow water wave equation in an ocean or a river,which we investigate in this paper.Using symbolic computation,we find out,on one hand,a set of bilinear auto-Backlund transformations,which could connect certain solutions of that equation with other solutions of that equation itself,and on the other hand,a set of similarity reductions,which could go from that equation to a known ordinary differential equation.The results in this paper depend on all the oceanic variable coefficients in that equation. 展开更多
关键词 OCEAN RIVER extended time-dependent(3+1)-dimensional shallow water wave equation bilinear auto-Bäcklund transformation similarity reduction symbolic computation
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Similarity Intelligence:Similarity Based Reasoning,Computing,and Analytics
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作者 Zhaohao Sun 《Journal of Computer Science Research》 2023年第3期1-14,共14页
Similarity has been playing an important role in computer science,artificial intelligence(AI)and data science.However,similarity intelligence has been ignored in these disciplines.Similarity intelligence is a process ... Similarity has been playing an important role in computer science,artificial intelligence(AI)and data science.However,similarity intelligence has been ignored in these disciplines.Similarity intelligence is a process of discovering intelligence through similarity.This article will explore similarity intelligence,similarity-based reasoning,similarity computing and analytics.More specifically,this article looks at the similarity as an intelligence and its impact on a few areas in the real world.It explores similarity intelligence accompanying experience-based intelligence,knowledge-based intelligence,and data-based intelligence to play an important role in computer science,AI,and data science.This article explores similarity-based reasoning(SBR)and proposes three similarity-based inference rules.It then examines similarity computing and analytics,and a multiagent SBR system.The main contributions of this article are:1)Similarity intelligence is discovered from experience-based intelligence consisting of data-based intelligence and knowledge-based intelligence.2)Similarity-based reasoning,computing and analytics can be used to create similarity intelligence.The proposed approach will facilitate research and development of similarity intelligence,similarity computing and analytics,machine learning and case-based reasoning. 展开更多
关键词 similarity intelligence similarity computing similarity analytics similarity-based reasoning Big data analytics Artificial intelligence Intelligent agents
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Design of ontology mapping framework and improvement of similarity computation 被引量:2
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作者 Zheng Liping Li Guangyao +1 位作者 Liang Yongquan Sha Jing 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2007年第3期641-645,共5页
Ontology heterogeneity is the primary obstacle for interoperation of ontologies. Ontology mapping is the best way to solve this problem. The key of ontology mapping is the similarity computation. At present, the metho... Ontology heterogeneity is the primary obstacle for interoperation of ontologies. Ontology mapping is the best way to solve this problem. The key of ontology mapping is the similarity computation. At present, the method of similarity computation is imperfect. And the computation quantity is high. To solve these problems, an ontology-mapping framework with a kind of hybrid architecture is put forward, with an improvement in the method of similarity computation. Different areas have different local ontologies. Two ontologies are taken as examples, to explain the specific mapping framework and improved method of similarity computation. These two ontologies are about classes and teachers in a university. The experimental results show that using this framework and improved method can increase the accuracy of computation to a certain extent. Otherwise, the quantity of computation can be decreased. 展开更多
关键词 ONTOLOGY ontology heterogeneity ontology mapping WORDNET similarity computation.
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Design and Implementation of FAQ Automatic Return System Based on Similarity Computation 被引量:2
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作者 ZHANG Liang CHEN Zhao-xiong HUANG He-yan 《Wuhan University Journal of Natural Sciences》 EI CAS 2006年第1期138-142,共5页
FAQ (frequently asked question) is widely used on the Internet, but most FAQ's asking and answering are not automatic. This paper introduces the design and imple mentation of a FAQ automatic return system based on ... FAQ (frequently asked question) is widely used on the Internet, but most FAQ's asking and answering are not automatic. This paper introduces the design and imple mentation of a FAQ automatic return system based on semantic similarity computation, including computation model choo sing, FAQ characters analyzing, FAQ data formal expressing, feature vector indexing, and weight computing and so on. According to FAQ features of sentence length short, two mapping, strong domain characteristics etc. Vector Space Model with special semantic process was selected in system, and corresponding algorithm of similarity computation was proposed too. Experiment shows that the system has a good performance for high frequent and common questions. 展开更多
关键词 FAQ VSM similarity computation information retrieval
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Hadoop-Based Similarity Computation System for Composed Documents 被引量:1
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作者 Xiaoming Zhang Zhipeng Qin +3 位作者 Xuwei Liu Qianyun Hou Baishuang Zhang Jie Wu 《Journal of Computer and Communications》 2015年第5期196-202,共7页
There exist a large number of composed documents in universities in the teaching process. Most of them are required to check the similarity for validation. A kind of similarity computation system is constructed for co... There exist a large number of composed documents in universities in the teaching process. Most of them are required to check the similarity for validation. A kind of similarity computation system is constructed for composed documents with images and text information. Firstly, each document is split and outputs two parts as images and text information. Then, these documents are compared by computing the similarities of images and text contents independently. Through Hadoop system, the text contents are easily and quickly separated. Experimental results show that the proposed system is efficient and practical. 展开更多
关键词 similarity computATION Composed DOCUMENTS Map REDUCE SYSTEM Integration
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Information mining and similarity computation for semi-/un-structured sentences from the social data 被引量:1
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作者 Peiying Zhang Xingzhe Huang Lei Zhang 《Digital Communications and Networks》 SCIE CSCD 2021年第4期518-525,共8页
In recent years,with the development of the social Internet of Things(IoT),all kinds of data accumulated on the network.These data,which contain a lot of social information and opinions.However,these data are rarely f... In recent years,with the development of the social Internet of Things(IoT),all kinds of data accumulated on the network.These data,which contain a lot of social information and opinions.However,these data are rarely fully analyzed,which is a major obstacle to the intelligent development of the social IoT.In this paper,we propose a sentence similarity analysis model to analyze the similarity in people’s opinions on hot topics in social media and news pages.Most of these data are unstructured or semi-structured sentences,so the accuracy of sentence similarity analysis largely determines the model’s performance.For the purpose of improving accuracy,we propose a novel method of sentence similarity computation to extract the syntactic and semantic information of the semi-structured and unstructured sentences.We mainly consider the subjects,predicates and objects of sentence pairs and use Stanford Parser to classify the dependency relation triples to calculate the syntactic and semantic similarity between two sentences.Finally,we verify the performance of the model with the Microsoft Research Paraphrase Corpus(MRPC),which consists of 4076 pairs of training sentences and 1725 pairs of test sentences,and most of the data came from the news of social data.Extensive simulations demonstrate that our method outperforms other state-of-the-art methods regarding the correlation coefficient and the mean deviation. 展开更多
关键词 Sentence similarity computation Information mining and computation Social data Internet of things Type of sentence pairs
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Four-Dimensional Computerized Tomography (4D-CT) Reconstruction Based on the Similarity Measure of Spatial Adjacent Images 被引量:9
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作者 ZHANG Shu-xu ZHOU Ling-hong +3 位作者 CHEN Guang-jie LIN Sheng-qu YE Yu-sheng ZHANG Hai-nan 《Chinese Journal of Biomedical Engineering(English Edition)》 2008年第3期106-113,共8页
Objective:To investigate the feasibility of a 4D-CT reconstruction method based on the similarity principle of spatial adjacent images and mutual information measure. Methods:A motor driven sinusoidal motion platform ... Objective:To investigate the feasibility of a 4D-CT reconstruction method based on the similarity principle of spatial adjacent images and mutual information measure. Methods:A motor driven sinusoidal motion platform made in house was used to create one-dimensional periodical motion that was along the longitudinal axis of the CT couch. The amplitude of sinusoidal motion was set to an amplitude of ±1 cm. The period of the motion was adjustable and set to 3.5 s. Phantom objects of two eggs were placed in a Styrofoam block, which in turn were placed on the motion platform. These objects were used to simulate volumes of interest undergoing ideal periodic motion. CT data of static phantom were acquired using a multi-slice general electric (GE) LightSpeed 16-slice CT scanner in an axial mode. And the CT data of periodical motion phantom were acquired in an axial and cine-mode scan. A software program was developed by using VC++ and VTK software tools to resort the CT data and reconstruct the 4D-CT. Then all of the CT data with same phase were sorted by the program into the same series based on the similarity principle of spatial adjacent images and mutual information measure among them, and 3D reconstruction of different phase CT data were completed by using the software. Results:All of the CT data were sorted accurately into different series based on the similarity principle of spatial adjacent images and mutual information measures among them. Compared with the unsorted CT data, the motion artifacts in the 3D reconstruction of sorted CT data were reduced significantly, and all of the sorted CT series result in a 4D-CT that reflected the characteristic of the periodical motion phantom. Conclusion:Time-resolved 4D-CT reconstruction can be implemented with any general multi-slice CT scanners based on the similarity principle of spatial adjacent images and mutual information measure.The process of the 4D-CT data acquisition and reconstruction were not restricted to the hardware or software of the CT scanner and has the feasibility ,which extensive applicability. 展开更多
关键词 PHANTOM four-dimensional computed tomography (4D-CT) reconstruc-tion similarity motion artifacts mutual information
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An integrated cognitive computing approach for systematic conceptual design 被引量:3
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作者 Hao ZHENG Yi-xiong FENG +2 位作者 Jian-rong TAN Zhi-feng ZHANG Zi-xian ZHANG 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2016年第4期286-294,共9页
Conceptual design plays an important role in product life cycle, which requires engineers to use sound design theory, cross-disciplinary knowledge, and complex technical support to acquire design concepts. However, th... Conceptual design plays an important role in product life cycle, which requires engineers to use sound design theory, cross-disciplinary knowledge, and complex technical support to acquire design concepts. However, the lack of sufficient computational tools makes it difficult for designers to fully explore in the wide design solution spaces. Therefore, this paper proposes an integrated cognitive computing approach to formalize the cognitive activities of conceptual design. A cognitive computing model composed of concept associative memory, concept generation, and decision-making process is established based on the integration of cognitive psychology and engineering design. First of all, the Hopfield neural network is used to acquire similar concept solutions for specific subfunctions from a knowledge base. Then, morphological matrix and genetic algorithm are introduced to produce a set of feasible candidate solutions in the concept generation process. Furthermore, a technique for order preference by similarity to an ideal solution is applied to evaluate the generated concept solutions and obtain the optimal solution automatically. Finally, a case study is given to demonstrate the effectiveness and efficiency of the proposed approach. 展开更多
关键词 Conceptual design Cognitive computing Genetic algorithm (GA) Technique for order preference by similarity to ideal solution (TOPSIS)
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Multi-core based parallel computing technique for content-based image retrieval 被引量:1
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作者 陈文浩 方昱春 +1 位作者 姚继锋 张武 《Journal of Shanghai University(English Edition)》 2010年第1期55-59,共5页
In this paper, we propose a parallel computing technique for content-based image retrieval (CBIR) system. This technique is mainly used for single node with multi-core processor, which is different from those based ... In this paper, we propose a parallel computing technique for content-based image retrieval (CBIR) system. This technique is mainly used for single node with multi-core processor, which is different from those based on cluster or network computing architecture. Due to its specific applications (such as medical image processing) and the harsh terms of hardware resource requirement, the CBIR system has been prevented from being widely used. With the increasing volume of the image database, the widespread use of multi-core processors, and the requirement of the retrieval accuracy and speed, we need to achieve a retrieval strategy which is based on multi-core processor to make the retrieval faster and more convenient than before. Experimental results demonstrate that this parallel architecture can significantly improve the performance of retrieval system. In addition, we also propose an efficient parallel technique with the combinations of the cluster and the multi-core techniques, which is supposed to gear to the new trend of the cloud computing. 展开更多
关键词 content-based image retrieval (CBIR) parallel computing SHARED-MEMORY feature extraction similarity comparison
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A New Method for Calculating Similarity between Sentences and Application on Automatic Abstracting 被引量:1
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作者 Wenqian JI Zhoujun LI +1 位作者 Wenhan CHAO Xiaoming CHEN 《Intelligent Information Management》 2009年第1期36-42,共7页
Sentence similarity computing plays an important role in machine question-answering systems, machine-translation systems, information retrieval and automatic abstracting systems. This article firstly sums up several m... Sentence similarity computing plays an important role in machine question-answering systems, machine-translation systems, information retrieval and automatic abstracting systems. This article firstly sums up several methods for calculating similarity between sentences, and brings out a new method which takes all factors into consideration including critical words, semantic information, sentential form and sen-tence length. And on this basis, a automatic abstracting system based on LexRank algorithm is implemented. We made several improvements in both sentence weight computing and redundancy resolution. The system described in this article could deal with single or multi-document summarization both in English and Chinese. With evaluations on two corpuses, our system could produce better summaries to a certain degree. We also show that our system is quite insensitive to the noise in the data that may result from an imperfect topical clustering of documents. And in the end, existing problem and the developing trend of automatic summariza-tion technology are discussed. 展开更多
关键词 SENTENCE similarity AUTOMATIC abstracting lexrank sentence-weight computing REDUNDANCY resolution
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Gershgorin and Rayleigh Bounds on the Eigenvalues of the Finite-Element Global Matrices via Optimal Similarity Transformations
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作者 Isaac Fried Roberto Riganti Chen Yu 《Applied Mathematics》 2020年第9期922-941,共20页
The large finite element global stiffness matrix is an algebraic, discreet, even-order, differential operator of zero row sums. Direct application of the, practically convenient, readily applied, Gershgorin’s eigenva... The large finite element global stiffness matrix is an algebraic, discreet, even-order, differential operator of zero row sums. Direct application of the, practically convenient, readily applied, Gershgorin’s eigenvalue bounding theorem to this matrix inherently fails to foresee its positive definiteness, predictably, and routinely failing to produce a nontrivial lower bound on the least eigenvalue of this, theoretically assured to be positive definite, matrix. Considered here are practical methods for producing an optimal similarity transformation for the finite-elements global stiffness matrix, following which non trivial, realistic, lower bounds on the least eigenvalue can be located, then further improved. The technique is restricted here to the common case of a global stiffness matrix having only non-positive off-diagonal entries. For such a matrix application of the Gershgorin bounding method may be carried out by a mere matrix vector multiplication. 展开更多
关键词 Finite Elements Global Stiffness Matrix Gershgorin and Rayleigh computed Upper and Lower Bounds on the Extremal Eigenvalues similarity Transformations
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A Fault Tolerance Algorithm for Resource Discovery in Semantic Grid Computing Using Task Agents
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作者 Masoud Barati Soheil Lotfi Azizallah Rahmati 《Journal of Software Engineering and Applications》 2014年第4期256-263,共8页
One of the interesting topics in grid computing systems is resources discovery. After the failure of a resource in a chain of resources made for a specific task in grid environment, discovering and finding a new resou... One of the interesting topics in grid computing systems is resources discovery. After the failure of a resource in a chain of resources made for a specific task in grid environment, discovering and finding a new resource that reconstructs the chain is an important topic. In this study, with defining new agent that is called task agent, and by proposing an algorithm, we will increase the fault tolerance against probable failure of a resource in the resource chain. 展开更多
关键词 Grid computing RESOURCE AGENT TASK AGENT Ontology SEMANTIC similarity Function
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Illegal Access Detection in the Cloud Computing Environment
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作者 Rasim Alguliev Fargana Abdullaeva 《Journal of Information Security》 2014年第2期65-71,共7页
In this paper detection method for the illegal access to the cloud infrastructure is proposed. Detection process is based on the collaborative filtering algorithm constructed on the cloud model. Here, first of all, th... In this paper detection method for the illegal access to the cloud infrastructure is proposed. Detection process is based on the collaborative filtering algorithm constructed on the cloud model. Here, first of all, the normal behavior of the user is formed in the shape of a cloud model, then these models are compared with each other by using the cosine similarity method and by applying the collaborative filtering method the deviations from the normal behavior are evaluated. If the deviation value is above than the threshold, the user who gained access to the system is evaluated as illegal, otherwise he is evaluated as a real user. 展开更多
关键词 CLOUD computing MASQUERADE ATTACK CLOUD Model User similarity COLLABORATIVE FILTERING
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Group Similarity and Social Influence Analysis in Online Communities
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作者 丁兆云 邹雪琴 +4 位作者 李越洋 乔凤才 程佳军 何速 王晖 《Journal of Donghua University(English Edition)》 EI CAS 2016年第5期755-758,共4页
A fundamental open question in the analysis of social networks was to understand the evolution between similarity and group social ties.In general,two groups are similar for two distinct reasons:first,they grow to cha... A fundamental open question in the analysis of social networks was to understand the evolution between similarity and group social ties.In general,two groups are similar for two distinct reasons:first,they grow to change their behaviors to the same group due to social influence;second,they tend to merge a group due to similar behaviors,where a process often is termed selection by sociologists.It was important to understand why two groups could merge and what led to high similarities for members in a group,influence or selection.In this paper,the techniques for identifying and modeling interactions between social influence and selection for different groups were developed.Different similarities were computed in three phases where groups came into being,before or after according to the number of common edits in Wikipedia.Experimental results showed selection played a more important role in two group merging. 展开更多
关键词 similarity merge merging identifying probabilistic validate seriously reasons maximization compute
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轨迹表示学习方法研究综述
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作者 孟祥福 孙硕男 +2 位作者 张霄雁 冷强奎 方金凤 《计算机科学与探索》 北大核心 2025年第6期1437-1454,共18页
全球定位系统(GPS)、全球移动通信系统(GSM)的快速发展以及移动设备的普遍应用,产生了大量的轨迹数据。目前的轨迹数据处理方法通常以定长的向量形式输入到模型,因此如何将变长的轨迹数据转换成定长低维的嵌入向量十分重要。轨迹表示学... 全球定位系统(GPS)、全球移动通信系统(GSM)的快速发展以及移动设备的普遍应用,产生了大量的轨迹数据。目前的轨迹数据处理方法通常以定长的向量形式输入到模型,因此如何将变长的轨迹数据转换成定长低维的嵌入向量十分重要。轨迹表示学习旨在将轨迹数据转换为更具表达力和可解释性的表示形式。对轨迹表示学习的研究现状、方法及应用进行了全面综述。分类介绍了轨迹表示学习的关键技术,总结了现有轨迹公开数据集。将轨迹表示学习方法按照不同的下游任务进行分类,重点综述了轨迹表示学习方法在轨迹相似性计算、相似轨迹搜索、轨迹聚类、轨迹预测等领域的原理、优缺点和应用,并分别分析了每一类任务中具有代表性的模型结构和原理,及各类任务中不同方法的特点和优势。分析了当前轨迹表示学习所面临的挑战,探讨了如何解决轨迹表示学习中的数据稀疏性、多模态以及模型优化与隐私保护等问题,并提出了具体的研究思路和方法。 展开更多
关键词 轨迹表示学习 轨迹数据挖掘 轨迹相似性计算 相似轨迹搜索 轨迹聚类 轨迹预测
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基于机器视觉与深度学习的烟用商标纸质量评价方法研究
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作者 王律 曹昌清 +11 位作者 斯勇 沈强 丁冉 林森 沈陟彦 薛辰 夏志骋 陈仁宇 许彦旻 张俊 彭云发 詹映 《中国造纸》 北大核心 2025年第11期192-199,共8页
为研究融合深度学习的机器视觉技术应用于烟用商标纸质量检测结果的评价,提出了一种综合评价方法。通过搭建高分辨率工业相机、定制光源及专用软件系统,构建图像标注数据集,采用动态阈值ORB特征检测、改进RANSAC配准优化及多波段融合策... 为研究融合深度学习的机器视觉技术应用于烟用商标纸质量检测结果的评价,提出了一种综合评价方法。通过搭建高分辨率工业相机、定制光源及专用软件系统,构建图像标注数据集,采用动态阈值ORB特征检测、改进RANSAC配准优化及多波段融合策略,有效消除拼接缝,图像PSNR值达38.9 dB,SSIM值为0.94。在要素识别任务中,基于YOLOv8模型引入CBAM注意力模块,结合ResNet-34骨干网络与FPN多尺度特征融合,测试集上mAP50达99.4%,召回率与精确率分别达99.6%和99.0%。设计双分支Siamese网络,融合SIFT描述子与深度语义特征计算相似度,小盒商标纸要素相似度平均准确率97.64%,条盒商标纸相似度平均准确率95.85%。 展开更多
关键词 机器视觉 深度学习 YOLOv8 商标纸质量检测 相似度计算
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基于多属性优势的松弛函数依赖的数据质量检测
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作者 唐雨薇 《计算机应用与软件》 北大核心 2025年第7期315-325,391,共12页
为了同时兼顾松弛函数依赖检测效果,并降低计算复杂度,提出一种基于多属性优势的松弛函数依赖的数据质量检测。提出一种松弛函数依赖的数据质量检测算法,该算法通过多属性决策理论中的优势概念将多属性值之间的距离表示为指标,从而能够... 为了同时兼顾松弛函数依赖检测效果,并降低计算复杂度,提出一种基于多属性优势的松弛函数依赖的数据质量检测。提出一种松弛函数依赖的数据质量检测算法,该算法通过多属性决策理论中的优势概念将多属性值之间的距离表示为指标,从而能够自动推断相似性阈值;引入一个效用函数可以根据松弛函数依赖的基数和阈值对其进行排序。最后,对真实数据集进行了实验评估,结果表明该方法具有较高的检测精度与较低的计算复杂度。 展开更多
关键词 多属性决策 松弛函数依赖 相似性阈值 计算复杂度
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基于PSNR和SSIM方法评估双能量CT肝脏虚拟平扫图像质量研究
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作者 李亚光 李洁 +5 位作者 薛廷玉 母建奎 王强 郑立冬 王勇 雷立存 《CT理论与应用研究(中英文)》 2025年第1期51-57,共7页
目的:采用峰值信噪比(PSNR)和结构相似性指数(SSIM)联合图像评价方法,探讨双能量CT的肝脏虚拟平扫(VNC)图像替代真实平扫(TNC)图像的可行性。方法:前瞻性分析33例肝脏CT平扫及Ⅲ期双能量增强扫描的影像学资料。经后处理获得动脉期VNC图... 目的:采用峰值信噪比(PSNR)和结构相似性指数(SSIM)联合图像评价方法,探讨双能量CT的肝脏虚拟平扫(VNC)图像替代真实平扫(TNC)图像的可行性。方法:前瞻性分析33例肝脏CT平扫及Ⅲ期双能量增强扫描的影像学资料。经后处理获得动脉期VNC图像(VNCa)、静脉期VNC图像(VNCv)及延迟期VNC图像(VNCd)。将肝脏Ⅲ期VNC图像与TNC图像应用PSNR和SSIM方法进行整体及局部比对分析。测量肝脏及竖脊肌的CT值与噪声值(SD),计算信噪比(SNR)和对比噪声比(CNR),记录肝脏真实CT平扫及增强扫描的剂量长度乘积,比较Ⅲ期VNC与TNC图像质量的客观评价指标及辐射剂量,并绘制肝脏CT值、SNR和CNR的Bland-Altman散点图进行一致性分析。结果:整体图像评价Ⅲ期VNC与TNC图像比对的PSNR分别为(18.01±1.06)、(18.33±0.99)、(18.20±1.04),SSIM分别为(0.76±0.04)、(0.77±0.03)、(0.78±0.04);局部图像评价Ⅲ期VNC与TNC图像比对的PSNR为(29.90±2.50)、(30.97±2.34)、(30.61±2.76),SSIM为(0.75±0.04)、(0.77±0.03)、(0.77±0.04);Ⅲ期VNC与TNC图像整体及局部比对的PSNR、SSIM的差异没有统计学意义。Ⅲ期VNC的肝脏CT值高于TNC;Ⅲ期VNC的CNR及VNCv的SNR与TNC图像相比无统计学差异;肝脏CT值、SNR及CNR在Ⅲ期VNC与TNC图像之间均具有良好的一致性。去除真实平扫环节,采用VNC+Ⅲ期增强方案可降低约29.63%的辐射剂量。结论:双能量CT的肝脏VNC图像具有良好的图像质量,可以较真实地还原TNC图像,满足临床的诊断需求。 展开更多
关键词 双能量CT 虚拟平扫 结构相似性指数 峰值信噪比
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