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1.
With the continuous development of intelligent transportation systems, vehicle-related fields have emerged a research boom in detection, tracking, and retrieval. Vehicle re-identification aims to judge whether a specific vehicle appears in a video stream, which is a popular research direction. Previous researches have proven that the transformer is an efficient method in computer vision, which treats a visual image as a series of patch sequences. However, an efficient vehicle re-identification should consider the image feature and the attribute feature simultaneously. In this work, we propose a vehicle attribute transformer (VAT) for vehicle re-identification. First, we consider color and model as the most intuitive attributes of the vehicle, the vehicle color and model are relatively stable and easy to distinguish. Therefore, the color feature and the model feature are embedded in a transformer. Second, we consider that the shooting angle of each image may be different, so we encode the viewpoint of the vehicle image as another additional attribute. Besides, different attributes are supposed to have different importance. Based on this, we design a multi-attribute adaptive aggregation network, which can compare different attributes and assign different weights to the corresponding features. Finally, to optimize the proposed transformer network, we design a multi-sample dispersion triplet (MDT) loss. Not only the hardest samples based on hard mining strategy, but also some extra positive samples and negative samples are considered in this loss. The dispersion of multi-sample is utilized to dynamically adjust the loss, which can guide the network to learn more optimized division for feature space. Extensive experiments on popular vehicle re-identification datasets verify that the proposed method can achieve state-of-the-art performance.  相似文献   

2.
Knowledge graphs are sizeable graph-structured knowledge with both abstract and concrete concepts in the form of entities and relations. Recently, convolutional neural networks have achieved outstanding results for more expressive representations of knowledge graphs. However, existing deep learning-based models exploit semantic information from single-level feature interaction, potentially limiting expressiveness. We propose a knowledge graph embedding model with an attention-based high-low level features interaction convolutional network called ConvHLE to alleviate this issue. This model effectively harvests richer semantic information and generates more expressive representations. Concretely, the multilayer convolutional neural network is utilized to fuse high-low level features. Then, features in fused feature maps interact with other informative neighbors through the criss-cross attention mechanism, which expands the receptive fields and boosts the quality of interactions. Finally, a plausibility score function is proposed for the evaluation of our model. The performance of ConvHLE is experimentally investigated on six benchmark datasets with individual characteristics. Extensive experimental results prove that ConvHLE learns more expressive and discriminative feature representations and has outperformed other state-of-the-art baselines over most metrics when addressing link prediction tasks. Comparing MRR and Hits@1 on FB15K-237, our model outperforms the baseline ConvE by 13.5% and 16.0%, respectively.  相似文献   

3.
[目的/意义]实体语义关系分类是信息抽取重要任务之一,将非结构化文本转化成结构化知识,是构建领域本体、知识图谱、开发问答系统、信息检索系统的基础工作。[方法/过程]本文详细梳理了实体语义关系分类的发展历程,从技术方法、应用领域两方面回顾和总结了近5年国内外的最新研究成果,并指出了研究的不足及未来的研究方向。[结果/结论]热门的深度学习方法抛弃了传统浅层机器学习方法繁琐的特征工程,自动学习文本特征,实验发现,在神经网络模型中融入词法、句法特征、引入注意力机制能有效提升关系分类性能。  相似文献   

4.
Extracting semantic relationships between entities from text documents is challenging in information extraction and important for deep information processing and management. This paper proposes to use the convolution kernel over parse trees together with support vector machines to model syntactic structured information for relation extraction. Compared with linear kernels, tree kernels can effectively explore implicitly huge syntactic structured features embedded in a parse tree. Our study reveals that the syntactic structured features embedded in a parse tree are very effective in relation extraction and can be well captured by the convolution tree kernel. Evaluation on the ACE benchmark corpora shows that using the convolution tree kernel only can achieve comparable performance with previous best-reported feature-based methods. It also shows that our method significantly outperforms previous two dependency tree kernels for relation extraction. Moreover, this paper proposes a composite kernel for relation extraction by combining the convolution tree kernel with a simple linear kernel. Our study reveals that the composite kernel can effectively capture both flat and structured features without extensive feature engineering, and easily scale to include more features. Evaluation on the ACE benchmark corpora shows that the composite kernel outperforms previous best-reported methods in relation extraction.  相似文献   

5.
Web2.0时代,阅读在线产品评论已经成为人们购物前的一种习惯。然而,网络上的评论数量巨大且观点不一,消费者很难获取到真正对其有用的评论。本文从研究中文在线产品评论的有用性评估入手,结合中文在线评论的特点,构建了评论有用性评估特征体系。以二分类思想为中心,基于文本挖掘的基本流程,实现对中文产品评论的分类,并考察了评论内容各特征对分类效果的影响。结果表明,本文提出的评估方法能有效识别出有用评论,并且发现浅层句法特征在分类中的贡献度较高,语义特征与情感特征则会因语料类型的不同而有不同的分类贡献度。  相似文献   

6.
Pedestrian gender recognition is a very challenging problem, since the viewpoint variations, illumination changes, occlusion, and poor quality are usually encountered in the pedestrian images. To address this problem, an effective HOG-assisted deep feature learning (HDFL) method is proposed in this paper. The key novelty lies in the design of HDFL network to effectively explore both deep-learned feature and weighted histogram of oriented gradient (HOG) feature for the pedestrian gender recognition. Specifically, the deep-learned and weighted HOG feature extraction branches are simultaneously performed on the input pedestrian image. A feature fusion process is subsequently conducted to obtain a more robust and discriminative feature, which is then fed to a softmax classifier for pedestrian gender recognition. Extensive experiments on multiple existing pedestrian image datasets have shown that the proposed HDFL method is able to effectively recognize the pedestrian gender, and consistently outperforms the state-of-the-art methods.  相似文献   

7.
This paper proposes a novel hierarchical learning strategy to deal with the data sparseness problem in semantic relation extraction by modeling the commonality among related classes. For each class in the hierarchy either manually predefined or automatically clustered, a discriminative function is determined in a top-down way. As the upper-level class normally has much more positive training examples than the lower-level class, the corresponding discriminative function can be determined more reliably and guide the discriminative function learning in the lower-level one more effectively, which otherwise might suffer from limited training data. In this paper, two classifier learning approaches, i.e. the simple perceptron algorithm and the state-of-the-art Support Vector Machines, are applied using the hierarchical learning strategy. Moreover, several kinds of class hierarchies either manually predefined or automatically clustered are explored and compared. Evaluation on the ACE RDC 2003 and 2004 corpora shows that the hierarchical learning strategy much improves the performance on least- and medium-frequent relations.  相似文献   

8.
左晓飞  刘怀亮  范云杰  赵辉 《情报杂志》2012,31(5):180-184,191
传统的基于关键词的文本聚类算法,由于难以充分利用文本的语义特征,聚类效果差强人意。笔者提出一种概念语义场的概念,并给出了基于知网构建概念语义场的算法。即首先利用知网构造义原屏蔽层,将描述能力弱的义原屏蔽,然后在分析知网结构的基础上给出抽取相关概念的规则,以及简单概念语义场和复杂概念语义场的构造方法。最后给出一种基于概念语义场的文本聚类算法。该算法可充分利用特征词的语义关系,对不规则形状的聚类也有较好效果。实验表明,该算法可以有效提高聚类的质量。  相似文献   

9.
Extracting semantic relationships between entities from text documents is challenging in information extraction and important for deep information processing and management. This paper investigates the incorporation of diverse lexical, syntactic and semantic knowledge in feature-based relation extraction using support vector machines. Our study illustrates that the base phrase chunking information is very effective for relation extraction and contributes to most of the performance improvement from syntactic aspect while current commonly used features from full parsing give limited further enhancement. This suggests that most of useful information in full parse trees for relation extraction is shallow and can be captured by chunking. This indicates that a cheap and robust solution in relation extraction can be achieved without decreasing too much in performance. We also demonstrate how semantic information such as WordNet, can be used in feature-based relation extraction to further improve the performance. Evaluation on the ACE benchmark corpora shows that effective incorporation of diverse features enables our system outperform previously best-reported systems. It also shows that our feature-based system significantly outperforms tree kernel-based systems. This suggests that current tree kernels fail to effectively explore structured syntactic information in relation extraction.  相似文献   

10.
基于改进特征提取及聚类的网络评论挖掘研究   总被引:1,自引:0,他引:1  
[目的/意义]针对信息过载条件下中文网络产品评论中特征提取性能低以及特征聚类中初始中心点的选取问题。[方法/过程]本研究提出采用基于权重的改进Apriori算法产生候选产品特征集合,再根据独立支持度、频繁项名词非特征规则及基于网络搜索引擎的PMI算法对候选产品特征集合进行过滤。并以基于HowNet的语义相似度和特征观点共现作为衡量产品特征之间关联程度的特征,提出一种改进K-means聚类算法对产品特征进行聚类。[结果/结论]实验结果表明,在特征提取阶段,查准率为69%,查全率为92.64%,综合值达到79.07%。在特征聚类阶段,本文提出的改进K-means算法相对传统算法具有更优的挖掘性能。  相似文献   

11.
本文将聚类分析引入竞争情报分析之中,构建了基于领域本体的竞争情报聚类分析模型。该模型利用竞争情报领域本体指导文本语义分析和标注,抽取特征概念和概念间关系,实现语义层面的文本表示;针对传统的聚类分析算法无法进行深层次的聚类分析,设计了一种基于语义核函数的聚类分析算法进行挖掘分析,实现深层次的聚类分析。实验结果表明,该模型取得了很好的预期效果,显著提高了竞争情报分析的准确率和效率。  相似文献   

12.
针对图书、期刊论文等数字文献文本特征较少而导致特征向量语义表达不够准确、分类效果差的问题,本文提出一种基于特征语义扩展的数字文献分类方法。该方法首先利用TF-IDF方法获取对数字文献文本表示能力较强、具有较高TF-IDF值的核心特征词;其次分别借助知网(Hownet)语义词典以及开放知识库维基百科(Wikipedia)对核心特征词集进行语义概念的扩展,以构建维度较低、语义丰富的概念向量空间;最后采用MaxEnt、SVM等多种算法构造分类器实现对数字文献的自动分类。实验结果表明:相比传统基于特征选择的短文本分类方法,该方法能有效地实现对短文本特征的语义扩展,提高数字文献分类的分类性能。  相似文献   

13.
Graph neural networks (GNN) have emerged as a new state-of-the-art for learning knowledge graph representations. Although they have shown impressive performance in recent studies, how to efficiently and effectively aggregate neighboring features is not well designed. To tackle this challenge, we propose the simplifying heterogeneous graph neural network (SHGNet), a generic framework that discards the two standard operations in GNN, including the transformation matrix and nonlinear activation. SHGNet, in particular, adopts only the essential component of neighborhood aggregation in GNN and incorporates relation features into feature propagation. Furthermore, to capture complex structures, SHGNet utilizes a hierarchical aggregation architecture, including node aggregation and relation weighting. Thus, the proposed model can treat each relation differently and selectively aggregate informative features. SHGNet has been evaluated for link prediction tasks on three real-world benchmark datasets. The experimental results show that SHGNet significantly promotes efficiency while maintaining superior performance, outperforming all the existing models in 3 out of 4 metrics on NELL-995 and in 4 out of 4 metrics on FB15k-237 dataset.  相似文献   

14.
余本功  王胡燕 《情报科学》2021,39(7):99-107
【目的/意义】对互联网产生的大量文本数据进行有效分类,提高文本处理效率,为企业用户决策提供建 议。【方法/过程】针对传统的词向量特征嵌入无法获取一词多义,特征稀疏、特征提取困难等问题,本文提出了一种 基于句子特征的多通道层次特征文本分类模型(SFM-DCNN)。首先,该模型通过Bert句向量建模,将特征嵌入从 传统的词特征嵌入升级为句特征嵌入,有效获取一词多义、词语位置及词间联系等语义特征。其次,通过构建多通 道深度卷积模型,将句特征从多层级来获取隐藏特征,获取更接近原语义的特征。【结果/结论】采用三种不同的数 据对模型进行验证分析,采用对比相关的分类方法,SFM-DCNN模型准确率较其他模型分类性能有所提高,这说 明该模型具有一定的借鉴意义。【创新/局限】基于文本分类中存在的一词多义、特征稀疏问题,创新性地利用Bert来 抽取全局语义信息,并结合多通道深层卷积来获取局部层次特征,但限于时间和设备条件,模型没有进行进一步的 预训练,实验数据集不够充分。  相似文献   

15.
Consumers evaluate products through online reviews, in addition to sharing their product experiences. Online reviews affect product marketing, and companies use online reviews to investigate consumer attitudes and perceptions of their products. However, when analyzing a review, it is often the case that specific contexts are not taken into consideration and meaningful information is not obtained from the analysis results. This study suggests a methodology for analyzing reviews in the context of comparing two competing products. In addition, by analyzing the discriminative attributes of competing products, we were able to derive more specific information than an overall product analysis. Analyzing the discriminative attributes in the context of comparing competing products provides clarity on analyzing the strengths and weaknesses of competitive products and provides realistic information that can help the company's management activities. Considering this purpose, this study collected a review of the BB Cream product line in the cosmetics field. The analysis was sequentially carried out in three stages. First, we extracted words that represent discriminative attributes by analyzing the percentage difference of words. Second, different attribute words were classified according to the meaning used in the review by using latent semantic analysis. Finally, the polarity of discriminative attribute words was analyzed using Labeled-LDA. This analysis method can be used as a market research method as it can extract more information than a traditional survey or interview method, and can save cost and time through the automation of the program.  相似文献   

16.
刘冰  庞琳 《情报理论与实践》2021,(3):172-177,163
[目的/意义]从用户角度,通过用户评价内容挖掘构建形成网络学术信息资源评价模型,为网络学术信息资源评价提供一个新的视角,并为其更进一步深入研究奠定基础。[方法/过程]文章在利用爬虫工作自动抓取三个知名学术网站用户评论的语料库基础上,运用数据挖掘研究方法对评论数据进行分词、聚类,根据词间与词对关系,构建形成评价体系模型。[结果/结论]基于用户评论挖掘构建形成涵盖资源内容属性、资源外部特征、网络功能属性、获取过程、用户体验五个维度的网络学术信息资源评价体系模型。该体系模型反映出科学用户在利用新兴网络学术信息资源过程中对资源自身属性和平台规范性的关切,是用户与利用正式学术信息资源的本质区别。  相似文献   

17.
Relation classification is one of the most fundamental tasks in the area of cross-media, which is essential for many practical applications such as information extraction, question&answer system, and knowledge base construction. In the cross-media semantic retrieval task, in order to meet the needs of cross-media uniform representation and semantic analysis, it is necessary to analyze the semantic potential relationship and construct semantic-related cross-media knowledge graph. The relationship classification technology is an important part of solving semantic correlation classification. Most of existing methods regard relation classification as a multi-classification task, without considering the correlation between different relationships. However, two relationships in the opposite directions are usually not independent of each other. Hence, this kind of relationships are easily confused in the traditional way. In order to solve the problem of confusing the relationships of the same semantic with different entity directions, this paper proposes a neural network fusing discrimination information for relation classification. In the proposed model, discrimination information is used to distinguish the relationship of the same semantic with different entity directions, the direction of entity in space is transformed into the direction of vector in mathematics by the method of entity vector subtraction, and the result of entity vector subtraction is used as discrimination information. The model consists of three modules: sentence representation module, relation discrimination module and discrimination fusion module. Moreover, two fusion methods are used for feature fusion. One is a Cascade-based feature fusion method, and another is a feature fusion method based on convolution neural network. In addition, this paper uses the new function added by cross-entropy function and deformed Max-Margin function as the loss function of the model. The experimental results show that the proposed discriminant feature is effective in distinguishing confusing relationships, and the proposed loss function can improve the performance of the model to a certain extent. Finally, the proposed model achieves 84.8% of the F1 value without any additional features or NLP analysis tools. Hence, the proposed method has a promising prospect of being incorporated in various cross-media systems.  相似文献   

18.
李勇男 《现代情报》2019,39(7):37-43
[目的/意义]利用子图模式对暴恐案件中的人员关联进行分析可以发现涉恐人员关联图中的规律,为反恐情报分析提供有效参考。[方法/过程]首先对涉恐基础数据进行预处理,保证图中各顶点的唯一性。通过计数统计出所有的频繁1-子图和频繁2-子图,然后不断迭代生成其他候选子图并筛选频繁子图,直到达到终止条件为止。[结果/结论]该方法根据反恐情报的特点进行了优化,避免了普通频繁子图挖掘中的大量图同构检测,挖掘出的频繁子图可以反映不同类别涉恐人员之间的联系规律和联系特点,发现暴恐案件线索,有效预测和打击恐怖活动。  相似文献   

19.
Measuring the similarity between the semantic relations that exist between words is an important step in numerous tasks in natural language processing such as answering word analogy questions, classifying compound nouns, and word sense disambiguation. Given two word pairs (AB) and (CD), we propose a method to measure the relational similarity between the semantic relations that exist between the two words in each word pair. Typically, a high degree of relational similarity can be observed between proportional analogies (i.e. analogies that exist among the four words, A is to B such as C is to D). We describe eight different types of relational symmetries that are frequently observed in proportional analogies and use those symmetries to robustly and accurately estimate the relational similarity between two given word pairs. We use automatically extracted lexical-syntactic patterns to represent the semantic relations that exist between two words and then match those patterns in Web search engine snippets to find candidate words that form proportional analogies with the original word pair. We define eight types of relational symmetries for proportional analogies and use those as features in a supervised learning approach. We evaluate the proposed method using the Scholastic Aptitude Test (SAT) word analogy benchmark dataset. Our experimental results show that the proposed method can accurately measure relational similarity between word pairs by exploiting the symmetries that exist in proportional analogies. The proposed method achieves an SAT score of 49.2% on the benchmark dataset, which is comparable to the best results reported on this dataset.  相似文献   

20.
[目的/意义] 提出一种基于在线产品评论的竞争情报挖掘框架,为企业改进产品设计和制定竞争策略提供参考。[方法/过程] 利用Word2vec技术构建产品特征词集合,识别用户评论主题特征。然后使用情感分析方法对评论文本进行分类,得到特征维度的评论情感。最后从产品主题特征和情感态度特征两方面进行数据分析,并以可视化结果呈现。[结果/结论] 以汽车行业的评论数据为例进行实验,结果表明该方法能够有效提取产品情报信息,帮助企业有效识别自身品牌及竞争对手的优势和劣势,为大数据环境下的竞争情报挖掘提供方法指导。  相似文献   

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