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Text-Image Feature Fine-Grained Learning for Joint Multimodal Aspect-Based Sentiment Analysis
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作者 Tianzhi Zhang Gang Zhou +4 位作者 Shuang Zhang Shunhang Li Yepeng Sun Qiankun Pi Shuo Liu 《Computers, Materials & Continua》 SCIE EI 2025年第1期279-305,共27页
Joint Multimodal Aspect-based Sentiment Analysis(JMASA)is a significant task in the research of multimodal fine-grained sentiment analysis,which combines two subtasks:Multimodal Aspect Term Extraction(MATE)and Multimo... Joint Multimodal Aspect-based Sentiment Analysis(JMASA)is a significant task in the research of multimodal fine-grained sentiment analysis,which combines two subtasks:Multimodal Aspect Term Extraction(MATE)and Multimodal Aspect-oriented Sentiment Classification(MASC).Currently,most existing models for JMASA only perform text and image feature encoding from a basic level,but often neglect the in-depth analysis of unimodal intrinsic features,which may lead to the low accuracy of aspect term extraction and the poor ability of sentiment prediction due to the insufficient learning of intra-modal features.Given this problem,we propose a Text-Image Feature Fine-grained Learning(TIFFL)model for JMASA.First,we construct an enhanced adjacency matrix of word dependencies and adopt graph convolutional network to learn the syntactic structure features for text,which addresses the context interference problem of identifying different aspect terms.Then,the adjective-noun pairs extracted from image are introduced to enable the semantic representation of visual features more intuitive,which addresses the ambiguous semantic extraction problem during image feature learning.Thereby,the model performance of aspect term extraction and sentiment polarity prediction can be further optimized and enhanced.Experiments on two Twitter benchmark datasets demonstrate that TIFFL achieves competitive results for JMASA,MATE and MASC,thus validating the effectiveness of our proposed methods. 展开更多
关键词 Multimodal sentiment analysis aspect-based sentiment analysis feature fine-grained learning graph convolutional network adjective-noun pairs
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Aspect-Level Sentiment Analysis of Bi-Graph Convolutional Networks Based on Enhanced Syntactic Structural Information
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作者 Junpeng Hu Yegang Li 《Journal of Computer and Communications》 2025年第1期72-89,共18页
Aspect-oriented sentiment analysis is a meticulous sentiment analysis task that aims to analyse the sentiment polarity of specific aspects. Most of the current research builds graph convolutional networks based on dep... Aspect-oriented sentiment analysis is a meticulous sentiment analysis task that aims to analyse the sentiment polarity of specific aspects. Most of the current research builds graph convolutional networks based on dependent syntactic trees, which improves the classification performance of the models to some extent. However, the technical limitations of dependent syntactic trees can introduce considerable noise into the model. Meanwhile, it is difficult for a single graph convolutional network to aggregate both semantic and syntactic structural information of nodes, which affects the final sentence classification. To cope with the above problems, this paper proposes a bi-channel graph convolutional network model. The model introduces a phrase structure tree and transforms it into a hierarchical phrase matrix. The adjacency matrix of the dependent syntactic tree and the hierarchical phrase matrix are combined as the initial matrix of the graph convolutional network to enhance the syntactic information. The semantic information feature representations of the sentences are obtained by the graph convolutional network with a multi-head attention mechanism and fused to achieve complementary learning of dual-channel features. Experimental results show that the model performs well and improves the accuracy of sentiment classification on three public benchmark datasets, namely Rest14, Lap14 and Twitter. 展开更多
关键词 aspect-Level sentiment Analysis sentiment Knowledge Multi-Head Attention Mechanism Graph Convolutional Networks
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Convolutional Multi-Head Self-Attention on Memory for Aspect Sentiment Classification 被引量:7
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作者 Yaojie Zhang Bing Xu Tiejun Zhao 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2020年第4期1038-1044,共7页
This paper presents a method for aspect based sentiment classification tasks, named convolutional multi-head self-attention memory network(CMA-Mem Net). This is an improved model based on memory networks, and makes it... This paper presents a method for aspect based sentiment classification tasks, named convolutional multi-head self-attention memory network(CMA-Mem Net). This is an improved model based on memory networks, and makes it possible to extract more rich and complex semantic information from sequences and aspects. In order to fix the memory network’s inability to capture context-related information on a word-level,we propose utilizing convolution to capture n-gram grammatical information. We use multi-head self-attention to make up for the problem where the memory network ignores the semantic information of the sequence itself. Meanwhile, unlike most recurrent neural network(RNN) long short term memory(LSTM), gated recurrent unit(GRU) models, we retain the parallelism of the network. We experiment on the open datasets Sem Eval-2014 Task 4 and Sem Eval-2016 Task 6. Compared with some popular baseline methods, our model performs excellently. 展开更多
关键词 aspect sentiment classification deep learning memory network sentiment analysis(SA)
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Aspect-Based Sentiment Analysis for Polarity Estimation of Customer Reviews on Twitter 被引量:1
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作者 Ameen Banjar Zohair Ahmed +2 位作者 Ali Daud Rabeeh Ayaz Abbasi Hussain Dawood 《Computers, Materials & Continua》 SCIE EI 2021年第5期2203-2225,共23页
Most consumers read online reviews written by different users before making purchase decisions,where each opinion expresses some sentiment.Therefore,sentiment analysis is currently a hot topic of research.In particula... Most consumers read online reviews written by different users before making purchase decisions,where each opinion expresses some sentiment.Therefore,sentiment analysis is currently a hot topic of research.In particular,aspect-based sentiment analysis concerns the exploration of emotions,opinions and facts that are expressed by people,usually in the form of polarity.It is crucial to consider polarity calculations and not simply categorize reviews as positive,negative,or neutral.Currently,the available lexicon-based method accuracy is affected by limited coverage.Several of the available polarity estimation techniques are too general and may not reect the aspect/topic in question if reviews contain a wide range of information about different topics.This paper presents a model for the polarity estimation of customer reviews using aspect-based sentiment analysis(ABSA-PER).ABSA-PER has three major phases:data preprocessing,aspect co-occurrence calculation(CAC)and polarity estimation.A multi-domain sentiment dataset,Twitter dataset,and trust pilot forum dataset(developed by us by dened judgement rules)are used to verify ABSA-PER.Experimental outcomes show that ABSA-PER achieves better accuracy,i.e.,85.7%accuracy for aspect extraction and 86.5%accuracy in terms of polarity estimation,than that of the baseline methods. 展开更多
关键词 Natural language processing sentiment analysis aspect co-occurrence calculation sentiment polarity customer reviews twitte
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Aspect based sentiment analysis using multi-criteria decision-making and deep learning under COVID-19 pandemic in India 被引量:2
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作者 Rakesh Dutta Nilanjana Das +1 位作者 Mukta Majumder Biswapati Jana 《CAAI Transactions on Intelligence Technology》 SCIE EI 2023年第1期219-234,共16页
The COVID-19 pandemic has a significant impact on the global economy and health.While the pandemic continues to cause casualties in millions,many countries have gone under lockdown.During this period,people have to st... The COVID-19 pandemic has a significant impact on the global economy and health.While the pandemic continues to cause casualties in millions,many countries have gone under lockdown.During this period,people have to stay within walls and become more addicted towards social networks.They express their emotions and sympathy via these online platforms.Thus,popular social media(Twitter and Facebook)have become rich sources of information for Opinion Mining and Sentiment Analysis on COVID-19-related issues.We have used Aspect Based Sentiment Analysis to anticipate the polarity of public opinion underlying different aspects from Twitter during lockdown and stepwise unlock phases.The goal of this study is to find the feelings of Indians about the lockdown initiative taken by the Government of India to stop the spread of Coronavirus.India-specific COVID-19 tweets have been annotated,for analysing the sentiment of common public.To classify the Twitter data set a deep learning model has been proposed which has achieved accuracies of 82.35%for Lockdown and 83.33%for Unlock data set.The suggested method outperforms many of the contemporary approaches(long shortterm memory,Bi-directional long short-term memory,Gated Recurrent Unit etc.).This study highlights the public sentiment on lockdown and stepwise unlocks,imposed by the Indian Government on various aspects during the Corona outburst. 展开更多
关键词 aspect based sentiment analysis bi-directional gated recurrent unit COVID-19 deep learning k-means clustering multi-criteria decision-making natural language processing
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Aspect-Based Sentiment Analysis for Social Multimedia:A Hybrid Computational Framework 被引量:1
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作者 Muhammad Rizwan Rashid Rana Saif Ur Rehman +4 位作者 Asif Nawaz Tariq Ali Azhar Imran Abdulkareem Alzahrani Abdullah Almuhaimeed 《Computer Systems Science & Engineering》 SCIE EI 2023年第8期2415-2428,共14页
People utilize microblogs and other social media platforms to express their thoughts and feelings regarding current events,public products and the latest affairs.People share their thoughts and feelings about various ... People utilize microblogs and other social media platforms to express their thoughts and feelings regarding current events,public products and the latest affairs.People share their thoughts and feelings about various topics,including products,news,blogs,etc.In user reviews and tweets,sentiment analysis is used to discover opinions and feelings.Sentiment polarity is a term used to describe how sentiment is represented.Positive,neutral and negative are all examples of it.This area is still in its infancy and needs several critical upgrades.Slang and hidden emotions can detract from the accuracy of traditional techniques.Existing methods only evaluate the polarity strength of the sentiment words when dividing them into positive and negative categories.Some existing strategies are domain-specific.The proposed model incorporates aspect extraction,association rule mining and the deep learning technique Bidirectional EncoderRepresentations from Transformers(BERT).Aspects are extracted using Part of Speech Tagger and association rulemining is used to associate aspects with opinion words.Later,classification was performed using BER.The proposed approach attained an average of 89.45%accuracy,88.45%precision and 85.98%recall on different datasets of products and Twitter.The results showed that the proposed technique achieved better than state-of-the-art sentiment analysis techniques. 展开更多
关键词 aspectS deep learning LEXICON sentiments REVIEWS
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Multi-Task Learning Model with Data Augmentation for Arabic Aspect-Based Sentiment Analysis 被引量:1
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作者 Arwa Saif Fadel Osama Ahmed Abulnaja Mostafa Elsayed Saleh 《Computers, Materials & Continua》 SCIE EI 2023年第5期4419-4444,共26页
Aspect-based sentiment analysis(ABSA)is a fine-grained process.Its fundamental subtasks are aspect termextraction(ATE)and aspect polarity classification(APC),and these subtasks are dependent and closely related.Howeve... Aspect-based sentiment analysis(ABSA)is a fine-grained process.Its fundamental subtasks are aspect termextraction(ATE)and aspect polarity classification(APC),and these subtasks are dependent and closely related.However,most existing works on Arabic ABSA content separately address them,assume that aspect terms are preidentified,or use a pipeline model.Pipeline solutions design different models for each task,and the output from the ATE model is used as the input to the APC model,which may result in error propagation among different steps because APC is affected by ATE error.These methods are impractical for real-world scenarios where the ATE task is the base task for APC,and its result impacts the accuracy of APC.Thus,in this study,we focused on a multi-task learning model for Arabic ATE and APC in which the model is jointly trained on two subtasks simultaneously in a singlemodel.This paper integrates themulti-task model,namely Local Cotext Foucse-Aspect Term Extraction and Polarity classification(LCF-ATEPC)and Arabic Bidirectional Encoder Representation from Transformers(AraBERT)as a shred layer for Arabic contextual text representation.The LCF-ATEPC model is based on a multi-head selfattention and local context focus mechanism(LCF)to capture the interactive information between an aspect and its context.Moreover,data augmentation techniques are proposed based on state-of-the-art augmentation techniques(word embedding substitution with constraints and contextual embedding(AraBERT))to increase the diversity of the training dataset.This paper examined the effect of data augmentation on the multi-task model for Arabic ABSA.Extensive experiments were conducted on the original and combined datasets(merging the original and augmented datasets).Experimental results demonstrate that the proposed Multi-task model outperformed existing APC techniques.Superior results were obtained by AraBERT and LCF-ATEPC with fusion layer(AR-LCF-ATEPC-Fusion)and the proposed data augmentation word embedding-based method(FastText)on the combined dataset. 展开更多
关键词 Arabic aspect extraction arabic sentiment classification AraBERT multi-task learning data augmentation
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Aspect Extraction Approach for Sentiment Analysis Using Keywords
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作者 Nafees Ayub Muhammad Ramzan Talib +1 位作者 Muhammad Kashif Hanif Muhammad Awais 《Computers, Materials & Continua》 SCIE EI 2023年第3期6879-6892,共14页
Sentiment Analysis deals with consumer reviews available on blogs,discussion forums,E-commerce websites,andApp Store.These online reviews about products are also becoming essential for consumers and companies as well.... Sentiment Analysis deals with consumer reviews available on blogs,discussion forums,E-commerce websites,andApp Store.These online reviews about products are also becoming essential for consumers and companies as well.Consumers rely on these reviews to make their decisions about products and companies are also very interested in these reviews to judge their products and services.These reviews are also a very precious source of information for requirement engineers.But companies and consumers are not very satisfied with the overall sentiment;they like fine-grained knowledge about consumer reviews.Owing to this,many researchers have developed approaches for aspect-based sentiment analysis.Most existing approaches concentrate on explicit aspects to analyze the sentiment,and only a few studies rely on capturing implicit aspects.This paper proposes a Keywords-Based Aspect Extraction method,which captures both explicit and implicit aspects.It also captures opinion words and classifies the sentiment about each aspect.We applied semantic similarity-basedWordNet and SentiWordNet lexicon to improve aspect extraction.We used different collections of customer reviews for experiment purposes,consisting of eight datasets over seven domains.We compared our approach with other state-of-the-art approaches,including Rule Selection using Greedy Algorithm(RSG),Conditional Random Fields(CRF),Rule-based Extraction(RubE),and Double Propagation(DP).Our results have shown better performance than all of these approaches. 展开更多
关键词 sentiment analysis aspect extraction keywords-based machine learning
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Aspect-Based Sentiment Classification Using Deep Learning and Hybrid of Word Embedding and Contextual Position
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作者 Waqas Ahmad Hikmat Ullah Khan +3 位作者 Fawaz Khaled Alarfaj Saqib Iqbal Abdullah Mohammad Alomair Naif Almusallam 《Intelligent Automation & Soft Computing》 SCIE 2023年第9期3101-3124,共24页
Aspect-based sentiment analysis aims to detect and classify the sentiment polarities as negative,positive,or neutral while associating them with their identified aspects from the corresponding context.In this regard,p... Aspect-based sentiment analysis aims to detect and classify the sentiment polarities as negative,positive,or neutral while associating them with their identified aspects from the corresponding context.In this regard,prior methodologies widely utilize either word embedding or tree-based rep-resentations.Meanwhile,the separate use of those deep features such as word embedding and tree-based dependencies has become a significant cause of information loss.Generally,word embedding preserves the syntactic and semantic relations between a couple of terms lying in a sentence.Besides,the tree-based structure conserves the grammatical and logical dependencies of context.In addition,the sentence-oriented word position describes a critical factor that influences the contextual information of a targeted sentence.Therefore,knowledge of the position-oriented information of words in a sentence has been considered significant.In this study,we propose to use word embedding,tree-based representation,and contextual position information in combination to evaluate whether their combination will improve the result’s effectiveness or not.In the meantime,their joint utilization enhances the accurate identification and extraction of targeted aspect terms,which also influences their classification process.In this research paper,we propose a method named Attention Based Multi-Channel Convolutional Neural Net-work(Att-MC-CNN)that jointly utilizes these three deep features such as word embedding with tree-based structure and contextual position informa-tion.These three parameters deliver to Multi-Channel Convolutional Neural Network(MC-CNN)that identifies and extracts the potential terms and classifies their polarities.In addition,these terms have been further filtered with the attention mechanism,which determines the most significant words.The empirical analysis proves the proposed approach’s effectiveness compared to existing techniques when evaluated on standard datasets.The experimental results represent our approach outperforms in the F1 measure with an overall achievement of 94%in identifying aspects and 92%in the task of sentiment classification. 展开更多
关键词 sentiment analysis word embedding aspect extraction consistency tree multichannel convolutional neural network contextual position information
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End-to-end aspect category sentiment analysis based on type graph convolutional networks
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作者 邵清 ZHANG Wenshuang WANG Shaojun 《High Technology Letters》 EI CAS 2023年第3期325-334,共10页
For the existing aspect category sentiment analysis research,most of the aspects are given for sentiment extraction,and this pipeline method is prone to error accumulation,and the use of graph convolutional neural net... For the existing aspect category sentiment analysis research,most of the aspects are given for sentiment extraction,and this pipeline method is prone to error accumulation,and the use of graph convolutional neural network for aspect category sentiment analysis does not fully utilize the dependency type information between words,so it cannot enhance feature extraction.This paper proposes an end-to-end aspect category sentiment analysis(ETESA)model based on type graph convolutional networks.The model uses the bidirectional encoder representation from transformers(BERT)pretraining model to obtain aspect categories and word vectors containing contextual dynamic semantic information,which can solve the problem of polysemy;when using graph convolutional network(GCN)for feature extraction,the fusion operation of word vectors and initialization tensor of dependency types can obtain the importance values of different dependency types and enhance the text feature representation;by transforming aspect category and sentiment pair extraction into multiple single-label classification problems,aspect category and sentiment can be extracted simultaneously in an end-to-end way and solve the problem of error accumulation.Experiments are tested on three public datasets,and the results show that the ETESA model can achieve higher Precision,Recall and F1 value,proving the effectiveness of the model. 展开更多
关键词 aspect-based sentiment analysis(ABSA) bidirectional encoder representation from transformers(BERT) type graph convolutional network(TGCN) aspect category and senti-ment pair extraction
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Improve Chinese Aspect Sentiment Quadruplet Prediction via Instruction Learning Based on Large Generate Models
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作者 Zhaoliang Wu Yuewei Wu +2 位作者 Xiaoli Feng Jiajun Zou Fulian Yin 《Computers, Materials & Continua》 SCIE EI 2024年第3期3391-3412,共22页
Aspect-Based Sentiment Analysis(ABSA)is a fundamental area of research in Natural Language Processing(NLP).Within ABSA,Aspect Sentiment Quad Prediction(ASQP)aims to accurately identify sentiment quadruplets in target ... Aspect-Based Sentiment Analysis(ABSA)is a fundamental area of research in Natural Language Processing(NLP).Within ABSA,Aspect Sentiment Quad Prediction(ASQP)aims to accurately identify sentiment quadruplets in target sentences,including aspect terms,aspect categories,corresponding opinion terms,and sentiment polarity.However,most existing research has focused on English datasets.Consequently,while ASQP has seen significant progress in English,the Chinese ASQP task has remained relatively stagnant.Drawing inspiration from methods applied to English ASQP,we propose Chinese generation templates and employ prompt-based instruction learning to enhance the model’s understanding of the task,ultimately improving ASQP performance in the Chinese context.Ultimately,under the same pre-training model configuration,our approach achieved a 5.79%improvement in the F1 score compared to the previously leading method.Furthermore,when utilizing a larger model with reduced training parameters,the F1 score demonstrated an 8.14%enhancement.Additionally,we suggest a novel evaluation metric based on the characteristics of generative models,better-reflecting model generalization.Experimental results validate the effectiveness of our approach. 展开更多
关键词 ABSA ASQP LLMs sentiment analysis Chinese comments
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Syntax-Based Aspect Sentiment Quad Prediction by Dual Modules Neural Network for Chinese Comments
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作者 Zhaoliang Wu Shanyu Tang +2 位作者 Xiaoli Feng Jiajun Zou Fulian Yin 《Computers, Materials & Continua》 SCIE EI 2023年第5期2873-2888,共16页
Aspect-Based Sentiment Analysis(ABSA)is one of the essential research in the field of Natural Language Processing(NLP),of which Aspect Sentiment Quad Prediction(ASQP)is a novel and complete subtask.ASQP aims to accura... Aspect-Based Sentiment Analysis(ABSA)is one of the essential research in the field of Natural Language Processing(NLP),of which Aspect Sentiment Quad Prediction(ASQP)is a novel and complete subtask.ASQP aims to accurately recognize the sentiment quad in the target sentence,which includes the aspect term,the aspect category,the corresponding opinion term,and the sentiment polarity of opinion.Nevertheless,existing approaches lack knowledge of the sentence’s syntax,so despite recent innovations in ASQP,it is poor for complex cyber comment processing.Also,most research has focused on processing English text,and ASQP for Chinese text is almost non-existent.Chinese usage is more casual than English,and individual characters contain more information.We propose a novel syntactically enhanced neural network framework inspired by syntax knowledge enhancement strategies in other NLP studies.In this framework,part of speech(POS)and dependency trees are input to the model as auxiliary information to strengthen its cognition of Chinese text structure.Besides,we design a relation extraction module,which provides a bridge for the overall extraction of the framework.A comparison of the designed experiments reveals that our proposed strategy outperforms the previous studies on the key metric F1.Further experiments demonstrate that the auxiliary information added to the framework improves the final performance in different ways. 展开更多
关键词 ABSA ASQP sentiment analysis Chinese comments
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Aspect-Level Sentiment Analysis Incorporating Semantic and Syntactic Information
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作者 Jiachen Yang Yegang Li +2 位作者 Hao Zhang Junpeng Hu Rujiang Bai 《Journal of Computer and Communications》 2024年第1期191-207,共17页
Aiming at the problem that existing models in aspect-level sentiment analysis cannot fully and effectively utilize sentence semantic and syntactic structure information, this paper proposes a graph neural network-base... Aiming at the problem that existing models in aspect-level sentiment analysis cannot fully and effectively utilize sentence semantic and syntactic structure information, this paper proposes a graph neural network-based aspect-level sentiment classification model. Self-attention, aspectual word multi-head attention and dependent syntactic relations are fused and the node representations are enhanced with graph convolutional networks to enable the model to fully learn the global semantic and syntactic structural information of sentences. Experimental results show that the model performs well on three public benchmark datasets Rest14, Lap14, and Twitter, improving the accuracy of sentiment classification. 展开更多
关键词 aspect-Level sentiment Analysis Attentional Mechanisms Dependent Syntactic Trees Graph Convolutional Neural Networks
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Aspect-Level Sentiment Analysis Based on Deep Learning
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作者 Mengqi Zhang Jiazhao Chai +2 位作者 Jianxiang Cao Jialing Ji Tong Yi 《Computers, Materials & Continua》 SCIE EI 2024年第3期3743-3762,共20页
In recent years,deep learning methods have developed rapidly and found application in many fields,including natural language processing.In the field of aspect-level sentiment analysis,deep learning methods can also gr... In recent years,deep learning methods have developed rapidly and found application in many fields,including natural language processing.In the field of aspect-level sentiment analysis,deep learning methods can also greatly improve the performance of models.However,previous studies did not take into account the relationship between user feature extraction and contextual terms.To address this issue,we use data feature extraction and deep learning combined to develop an aspect-level sentiment analysis method.To be specific,we design user comment feature extraction(UCFE)to distill salient features from users’historical comments and transform them into representative user feature vectors.Then,the aspect-sentence graph convolutional neural network(ASGCN)is used to incorporate innovative techniques for calculating adjacency matrices;meanwhile,ASGCN emphasizes capturing nuanced semantics within relationships among aspect words and syntactic dependency types.Afterward,three embedding methods are devised to embed the user feature vector into the ASGCN model.The empirical validations verify the effectiveness of these models,consistently surpassing conventional benchmarks and reaffirming the indispensable role of deep learning in advancing sentiment analysis methodologies. 展开更多
关键词 aspect-level sentiment analysis deep learning graph convolutional neural network user features syntactic dependency tree
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自动化ASPECTS评估急性缺血性脑卒中的人机对比研究
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作者 许萍 程晓青 +6 位作者 周长圣 田冰 田霞 石峰 曹泽红 高敏 邢伟 《医学研究与战创伤救治》 北大核心 2025年第4期370-375,共6页
目的探讨自动化Alberta卒中项目早期CT评分(ASPECTS)与专家评分的相关性、一致性,并比较两者预测良好临床预后的效能。方法回顾性分析2015年5月至2022年1月在苏州大学附属第三医院、东部战区总医院、上海长海医院绿色卒中通道的急性缺... 目的探讨自动化Alberta卒中项目早期CT评分(ASPECTS)与专家评分的相关性、一致性,并比较两者预测良好临床预后的效能。方法回顾性分析2015年5月至2022年1月在苏州大学附属第三医院、东部战区总医院、上海长海医院绿色卒中通道的急性缺血性脑卒中患者的临床资料。收集所有患者的入院平扫CT图像以及临床资料,自动化ASPECTS软件与神经放射学专家对平扫CT图像进行回顾性ASPECTS评估。Spearman分析自动化ASPECTS与专家评分的相关性,组内相关系数(ICC)用于评估一致性,受试者工作特性(ROC)曲线和DeLong检验评估和比较两者预测良好临床预后的效能。结果自动化ASPECTS与专家评分呈显著正相关(r=0.459,P<0.05),两者一致性较好(ICC=0.620)。自动化ASPECTS预测良好临床预后特异度高于专家(62.1%vs 41.1%),但灵敏度略低于专家(57.6%vs 73.7%),ROC曲线下面积均为0.605,DeLong检验两者差异无统计学意义(P=0.984)。结论自动化ASPECTS与专家评分呈显著正相关,两者间一致性好。在预测良好临床预后方面,两者评估效能相当。 展开更多
关键词 自动化Alberta卒中项目早期CT评分 急性缺血性脑卒中 计算机体层成像
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Phase field modeling of the aspect ratio dependent functional properties of NiTi shape memory alloys with different grain sizes 被引量:1
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作者 Bo Xu Beihai Huang +1 位作者 Chong Wang Qingyuan Wang 《Acta Mechanica Sinica》 2025年第1期22-41,共20页
It is well known that coarse-grained super-elastic NiTi shape memory alloys(SMAs)exhibit localized rather than homogeneous martensite transformation(MT),which,however,can be strongly influenced by either internal size... It is well known that coarse-grained super-elastic NiTi shape memory alloys(SMAs)exhibit localized rather than homogeneous martensite transformation(MT),which,however,can be strongly influenced by either internal size(grain size,GS)or the external size(geometric size).The coupled effect of GS and geometric size on the functional properties has not been clearly understood yet.In this work,the super-elasticity,one-way,and stress-assisted two-way shape memory effects of the polycrystalline NiTi SMAs with different aspect ratios(length/width for the gauge section)and different GSs are investigated based on the phase field method.The coupled effect of the aspect ratio and GS on the functional properties is adequately revealed.The simulated results indicate that when the aspect ratio is lower than about 4:1,the stress biaxiality and stress heterogeneity in the gauge section of the sample become more and more obvious with decreasing the aspect ratio,which can significantly influence the microstructure evolution in the process involving external stress.Therefore,the corresponding functional property is strongly dependent on the aspect ratio.With decreasing the GS and the aspect ratio(to be lower than 4:1),both the aspect ratio and GS can affect the MT or martensite reorientation in each grain and the interaction among grains.Thus,due to the strong internal constraint(i.e.,the constraint of grain boundary)and the external constraint(i.e.,the constraint of geometric boundary),the capabilities of the functional properties of NiTi SMAs are gradually weakened and highly dependent on these two factors. 展开更多
关键词 Phase field modeling NITI aspect ratio Grain size Functional property
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AI-Driven Sentiment-Enhanced Secure IoT Communication Model Using Resilience Behavior Analysis 被引量:1
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作者 Menwa Alshammeri Mamoona Humayun +1 位作者 Khalid Haseeb Ghadah Naif Alwakid 《Computers, Materials & Continua》 2025年第7期433-446,共14页
Wireless technologies and the Internet of Things(IoT)are being extensively utilized for advanced development in traditional communication systems.This evolution lowers the cost of the extensive use of sensors,changing... Wireless technologies and the Internet of Things(IoT)are being extensively utilized for advanced development in traditional communication systems.This evolution lowers the cost of the extensive use of sensors,changing the way devices interact and communicate in dynamic and uncertain situations.Such a constantly evolving environment presents enormous challenges to preserving a secure and lightweight IoT system.Therefore,it leads to the design of effective and trusted routing to support sustainable smart cities.This research study proposed a Genetic Algorithm sentiment-enhanced secured optimization model,which combines big data analytics and analysis rules to evaluate user feedback.The sentiment analysis is utilized to assess the perception of network performance,allowing the classification of device behavior as positive,neutral,or negative.By integrating sentiment-driven insights,the IoT network adjusts the system configurations to enhance the performance using network behaviour in terms of latency,reliability,fault tolerance,and sentiment score.Accordingly to the analysis,the proposed model categorizes the behavior of devices as positive,neutral,or negative,facilitating real-time monitoring for crucial applications.Experimental results revealed a significant improvement in the proposed model for threat prevention and network efficiency,demonstrating its resilience for real-time IoT applications. 展开更多
关键词 Internet of things sentiment analysis smart cities big data resilience communication
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急性基底动脉闭塞性卒中PC-ASPECTS评分与PMT评分的一致性比较
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作者 柯烨 何野 +1 位作者 石冉 王朋 《安徽医专学报》 2025年第1期28-31,共4页
目的:评估急性基底动脉闭塞性卒中患者基于头颅磁共振(MRI)的后循环阿尔伯塔卒中计划早期计算机断层扫描评分(PC-ASPECTS)及脑桥中脑-丘脑评分(PMT)等影像学评分的一致性。方法:前瞻性纳入32例急性基底动脉闭塞性卒中患者。由12名临床... 目的:评估急性基底动脉闭塞性卒中患者基于头颅磁共振(MRI)的后循环阿尔伯塔卒中计划早期计算机断层扫描评分(PC-ASPECTS)及脑桥中脑-丘脑评分(PMT)等影像学评分的一致性。方法:前瞻性纳入32例急性基底动脉闭塞性卒中患者。由12名临床医师对MRI进行评分,评分数据用于最后的一致性分析,即总体一致性及二分法后的一致性。结果:二分法前,基于MRI的PC-ASPECTS评分与PMT评分的总体组间一致性均达到了良好的水平(κ=0.791[95%CI,0.732-0.843];κ=0.684[95%CI,0.603-0.724])。在二分法后,PC-ASPECTS评分总体医师的组间一致性达到了优秀的水平(κ=0.824[95%CI,0.738-0.912]);而PMT评分的总体医师的组间一致性仍然处于良好的水平(κ=0.769[95%CI,0.693-0.859])。结论:相比于PMT评分,临床医生在评估基于MRI的PCASPECTS评分时,在给予一定的容差范畴的情况下,其一致性的值更高,足以支持可重复的临床决策和评估。 展开更多
关键词 脑卒中 一致性 PC-aspectS评分 PMT评分
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Investor sentiment networks:mapping connectedness in DJIA stocks
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作者 Kingstone Nyakurukwa Yudhvir Seetharam 《Financial Innovation》 2025年第1期64-82,共19页
This study examines the connectedness of firm-level online investor sentiment using Dow Jones Industrial Average constituent stocks.Leveraging two proxies of online textual sentiment,namely news media and social media... This study examines the connectedness of firm-level online investor sentiment using Dow Jones Industrial Average constituent stocks.Leveraging two proxies of online textual sentiment,namely news media and social media sentiment,we investigate sentiment connectedness at two levels:frequency interval and asymmetric level.Frequency connectedness dissects connectedness into short-,medium-,and long-term investing horizons,while asymmetric connectedness focuses on the transmission of positive and negative sentiment shocks on news and social media platforms.Our results reveal interesting patterns in which both news and social media sentiments demonstrate consistency in connectedness across the short-,medium-,and long-term.Regarding asymmetric connectedness,we observe that negative news sentiment has a higher connectedness than positive news sentiments. 展开更多
关键词 Behavioral finance sentiment contagion Social media sentiment News media sentiment
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Correlation Analysis Between Investor Sentiment and Stock Price Fluctuations Based on Large Language Models
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作者 Guohua Ren Ziyu Luo +1 位作者 Naiwen Zhang Yichen Yang 《Journal of Electronic Research and Application》 2025年第5期30-37,共8页
The efficient market hypothesis in traditional financial theory struggles to explain the short-term irrational fluctuations in the A-share market,where investor sentiment fluctuations often serve as the core driver of... The efficient market hypothesis in traditional financial theory struggles to explain the short-term irrational fluctuations in the A-share market,where investor sentiment fluctuations often serve as the core driver of abnormal stock price movements.Traditional sentiment measurement methods suffer from limitations such as lag,high misjudgment rates,and the inability to distinguish confounding factors.To more accurately explore the dynamic correlation between investor sentiment and stock price fluctuations,this paper proposes a sentiment analysis framework based on large language models(LLMs).By constructing continuous sentiment scoring factors and integrating them with a long short-term memory(LSTM)deep learning model,we analyze the correlation between investor sentiment and stock price fluctuations.Empirical results indicate that sentiment factors based on large language models can generate an annualized excess return of 9.3%in the CSI 500 index domain.The LSTM stock price prediction model incorporating sentiment features achieves a mean absolute percentage error(MAPE)as low as 2.72%,significantly outperforming traditional models.Through this analysis,we aim to provide quantitative references for optimizing investment decisions and preventing market risks. 展开更多
关键词 Large language model Investor sentiment Stock return prediction sentiment analysis LSTM
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