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颈动脉斑块MRI特征与同侧急性脑梗死患者DWIGASPECTS的相关性研究 被引量:2
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作者 王贝茹 余苗 +2 位作者 徐彤彤 李均彪 胡春峰 《放射学实践》 CSCD 北大核心 2024年第1期49-54,共6页
目的:探讨颈动脉斑块MRI特征与同侧急性脑梗死患者DWI-ASPECTS的相关性。方法:回顾性搜集我院85例颈动脉斑块患者的临床及影像资料,所有患者均于出现脑血管症状2周内行颈动脉高分辨率MRI和常规颅脑MRI平扫。将患者分为DWI-ASPECTS≤7分... 目的:探讨颈动脉斑块MRI特征与同侧急性脑梗死患者DWI-ASPECTS的相关性。方法:回顾性搜集我院85例颈动脉斑块患者的临床及影像资料,所有患者均于出现脑血管症状2周内行颈动脉高分辨率MRI和常规颅脑MRI平扫。将患者分为DWI-ASPECTS≤7分组和DWI-ASPECTS>7分组,比较两组间临床、实验室资料和颈动脉斑块定量、定性指标的差异。通过Logistic回归筛选DWI-ASPECTS评分的预测因子。结果:25例(29.4%)DWI-ASPECTS≤7分,60例(70.6%)DWI-ASPECTS>7分。DWI-ASPECTS≤7分组患者纤维帽变薄/破裂(分别为80.0%和35.0%,P<0.001)、斑块内出血(分别为72.0%和21.7%,P<0.001)、钙化(分别为76.0%和45.0%,P=0.009)和富脂质坏死核心(分别为72.0%和45.0%,P=0.023)的发生率均高于DWI-ASPECTS>7分组;此外,DWI-ASPECTS≤7分组患者显示出更高的斑块负荷,DWI-ASPECTS≤7分组与DWI-ASPECTS>7分组的最大管壁厚度[分别为(4.38±1.68)和(3.47±1.78)mm,P=0.033]、平均管腔面积[分别为(15.33±11.57)和(22.88±13.95)mm 2,P=0.019]、最小管腔面积[分别为(11.52±11.23)和(18.98±13.52)mm 2,P=0.017]、平均管壁面积[分别为(62.81±14.32)、(55.66±14.93)mm 2,P=0.045]、最大管壁面积[分别为(66.70±14.57)、(59.56±15.19)mm 2,P=0.049]、平均标准化管壁面指数[分别为(81±14)%、(71±16)%,P=0.011]、最大标准化管壁指数[分别为(86±14)%、(76±16)%,P=0.012)]差异均有统计学意义。DWI-ASPECTS≤7分组中NIHSS评分>4分的患者比例更高(分别为48%和23.3%,P=0.025),高密度脂蛋白浓度更低[分别为(1.24±0.28)、(1.10±0.28)mmol/L,P=0.043]。Logistic回归分析结果显示,纤维帽变薄/破裂(OR=4.133,95%CI:1.151~14.836,P=0.030)和斑块内出血(OR=6.409,95%CI:1.737~23.646,P=0.005)与较低的DWI-ASPECTS评分显著相关。结论:颈动脉斑块中存在纤维帽变薄/破裂和斑块内出血的急性脑卒中患者DWI-ASPECTS评分更低,有助于评估患者的病情严重程度。 展开更多
关键词 颈动脉斑块 磁共振成像 DWI-aspectS评分 急性脑梗死
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Elliptical vibration chiseling:a novel process for texturing ultra-high-aspect-ratio microstructures on the metallic surface
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作者 Zhiwei Li Jianfu Zhang +3 位作者 Zhongpeng Zheng Pingfa Feng Dingwen Yu Jianjian Wang 《International Journal of Extreme Manufacturing》 SCIE EI CAS CSCD 2024年第2期449-467,共19页
High-aspect-ratio metallic surface microstructures are increasingly demanded in breakthrough applications,such as high-performance heat transfer enhancement and surface plasmon devices.However,the fast and cost-effect... High-aspect-ratio metallic surface microstructures are increasingly demanded in breakthrough applications,such as high-performance heat transfer enhancement and surface plasmon devices.However,the fast and cost-effective fabrication of high-aspect-ratio microstructures on metallic surfaces remains challenging for existing techniques.This study proposes a novel cutting-based process,namely elliptical vibration chiseling(EV-chiseling),for the high-efficiency texturing of surface microstructures with an ultrahigh aspect ratio.Unlike conventional cutting,EV-chiseling superimposes a microscale EV on a backward-moving tool.The tool chisels into the material in each vibration cycle to generate an upright chip with a high aspect ratio through material deformation.Thanks to the tool’s backward movement,the chip is left on the material surface to form a microstructure rather than falling off.Since one microstructure is generated in one vibration cycle,the process can be highly efficient using ultrafast(>1 kHz)tool vibration.A finite element analysis model is established to explore the process mechanics of EV-chiseling.Next,a mechanistic model of the microstructured surface generation is developed to describe the microstructures’aspect ratio dependency on the process parameters.Then,surface texturing tests are performed on copper to verify the efficacy of EV-chiseling.Uniformed micro ribs with a spacing of 1–10μm and an aspect ratio of 2–5 have been successfully textured on copper.Compared with the conventional EV-cutting that uses a forward-moving tool,EV-chiseling can improve the aspect ratio of textured microstructure by up to 40 times.The experimental results also verify the accuracy of the developed surface generation model of microstructures.Finally,the effects of elliptical trajectory,depth of cut,tool shape,and tool edge radius on the surface generation of micro ribs have been discussed. 展开更多
关键词 metallic microstructure high aspect ratio backward-moving cutting vibration cutting chiseling material deformation
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ASPECTS评分及多模态CT定量分析在AIS预后预测中的应用
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作者 王书芹 郑璇 +1 位作者 孟影 朱广辉 《中国CT和MRI杂志》 2024年第11期4-6,共3页
目的探讨ASPECTS评分及多模态CT中各参数在急性缺血性脑卒中(AIS)预后预测的应用价值。方法收集2019年1月-2023年4月诊断为AIS并在蚌埠医学院第一附属医院就诊的患者,在治疗前均行多模态CT(包括NCCT、CTA、CTP)检查的患者93例,3个月后... 目的探讨ASPECTS评分及多模态CT中各参数在急性缺血性脑卒中(AIS)预后预测的应用价值。方法收集2019年1月-2023年4月诊断为AIS并在蚌埠医学院第一附属医院就诊的患者,在治疗前均行多模态CT(包括NCCT、CTA、CTP)检查的患者93例,3个月后随访并根据改良Rankin量表评分(mRs)将患者分为预后良好组(mRs≤2)和预后不良组(mRs>2),收集两组患者的临床资料及多模态CT定量参数比较其在预测AIS中预后中有无意义。结果一般资料分析可见预后不良组患者入院基线NIHSS评分、远端侧支循环及ASPECTS评分均与预后良好组之间有一定的统计学差异(P<0.05);CT灌注定量参数分析可见预后不良组CBF较低,而MTT、Tmax、TTP较预后良好组延长,且具有统计学意义(P<0.05)。其中NIHSS、远端侧支循环及Tmax为影响AIS预后的独立危险因素。结论NIHSS、远端侧支循环、ASPECTS及多模态CT可以对AIS的预后进行评测。均具有较好的预测效能,其中Tmax及NIHSS预测效能最好。 展开更多
关键词 脑卒中 aspectS评分 多模态CT CT灌注
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Management of Significant Environmental Aspects and Impacts in Accordance with the ISO 14001:2015 Standard during the Operation and Maintenance Phase of Senegal River Basin Development Authority Hydroelectric Works and Facilities: The Case of Manantali Dam
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作者 Joseph Mbeur Faye Saïdou Ndao Louis Eugène Victor Sambou 《Journal of Geoscience and Environment Protection》 2024年第10期89-110,共22页
This study aims to determine the environmental aspects and impacts of the phase relating to the operation of Manantali’s hydroelectric structures and facilities according to the requirements of the ISO 14001 version ... This study aims to determine the environmental aspects and impacts of the phase relating to the operation of Manantali’s hydroelectric structures and facilities according to the requirements of the ISO 14001 version 2015 standard. To do this, the mapping of the different work areas made it possible to identify all the activities within the framework of the farm. Based on the mapping, environmental measurements made including noise level, brightness, electric and magnetic fields, total particles, PM10, PM2.5, PM1 showed the work areas with the exposure limit values exceeded. The inventories of the waste produced show eighteen (18) types of waste, 67% of which are special industrial waste (SIW), 28% are ordinary industrial waste (OIW) and 5% are inert industrial waste (IIW). The identification and assessment of environmental aspects and impacts made it possible to determine sixteen (16) positive and negative significant environmental aspects (ESAs). The positive AES must be maintained, and for the negative ones, mitigation and mitigation measures must be put in place in order to manage them effectively. This will ultimately improve environmental management in the operation of hydroelectric structures and facilities. 展开更多
关键词 Manantali Environmental aspect Environmental Impact Waste Mitigation and Mitigation Measures
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Study on the Influence of Aspect Ratio on the Seismic Response and Overturning Resistance of a New Staggered Story Isolated Structure
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作者 Tiange Zhao Dewen Liu 《World Journal of Engineering and Technology》 2024年第3期617-634,共18页
The aspect ratio of the structure has a significant impact on the overall stability of the ultra high-rise building. A large aspect ratio of the structure increases the risk of overturning and reduces the lateral stif... The aspect ratio of the structure has a significant impact on the overall stability of the ultra high-rise building. A large aspect ratio of the structure increases the risk of overturning and reduces the lateral stiffness of the structure, leading to significant tensile and compressive stresses in the isolated bearings. To study the effect of aspect ratio on the seismic response and overturning resistance of a new staggered story isolated structure, three models with different aspect ratios were established. Nonlinear time-history analysis of the three models was conducted using ETABS finite element software. The results indicate that the overturning moment and overturning resistance moment of the superstructure in the new staggered story isolated structure increase with an increasing aspect ratio. However, the increase in the overturning moment of the superstructure is much greater than the increase in the overturning resistance moment, resulting in a decrease in the overturning resistance ratio of the superstructure with an increasing aspect ratio. The overturning moment and overturning resistance moment of the substructure in the new staggered story isolated structure decrease with an increasing aspect ratio. However, the decrease in the overturning moment of the substructure is greater than the decrease in the overturning resistance moment, leading to an increase in the overturning resistance ratio of the substructure with an increasing aspect ratio. The decrease in the overturning resistance ratio of the superstructure in the new staggered story isolated structure is much greater than the increase in the overturning resistance ratio of the substructure. Therefore, as the aspect ratio of the overall structure increases, the overturning resistance ratio of the superstructure and the entire structure decreases. 展开更多
关键词 aspect Ratio A New Staggered Story Isolated Structure Seismic Response Overturning Resistance Ratio Isolated Bearing
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Psychosocial Aspects of Male Infertility at the Service of Urology-Andrology of the Hospital of the Sino-Guinean Friendship
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作者 Alimou Diallo Thierno Oumar Diallo +3 位作者 Alpha Oumar Barry Ibrahima Bah Abdoulaye Bobo Diallo Oumar Raphiou Bah 《Open Journal of Urology》 2024年第7期400-406,共7页
Objective: Describe the psychosocial aspects of male infertility at the hospital of the Sino-Guinean Friendship. Patients and method: It is a prospective study of a descriptive type covering a period of 6 months. The ... Objective: Describe the psychosocial aspects of male infertility at the hospital of the Sino-Guinean Friendship. Patients and method: It is a prospective study of a descriptive type covering a period of 6 months. The study covered 17 patients, all received for a desire to conceive after at least one year of regular sexual intercourse without contraception. The data were collected from patient interviews using a pre-established questionnaire. Results: The average age of the patients was 32.07 years with extremes of 23 years and 42 years. During this study, 64.70% of patients were no longer participating in community ceremonies. The patients’ relationships with their spouse and family deteriorated in 52.94% and 47.06%, respectively. Conversely, relations with the family of origin remained unchanged in 70.59 percent of cases. The reduction in economic activity was by 13 patients (76.48%). Conclusion: Male infertility causes a real psychic earthquake in men with its corollaries of negative feelings. The rather complex moral repercussions of male infertility affect not only the individual, his/her partner, and family, but also economic activity. 展开更多
关键词 Male Infertility Psycho-Social aspect Psychic Earthquake
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一种基于预训练模型掩码Aspect术语的数据增强方法
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作者 石晓瑞 《信息技术与信息化》 2024年第2期103-108,共6页
数据增强是解决低资源场景下数据稀缺问题的有效方案。然而,当应用于诸如方面术语提取(ATE)之类的词级别任务时,数据增强方法通常会遭受词标签不对齐的问题,从而导致效果不理想。对此提出了掩码方面语言建模(MALM)作为ATE的新型数据增... 数据增强是解决低资源场景下数据稀缺问题的有效方案。然而,当应用于诸如方面术语提取(ATE)之类的词级别任务时,数据增强方法通常会遭受词标签不对齐的问题,从而导致效果不理想。对此提出了掩码方面语言建模(MALM)作为ATE的新型数据增强框架。为了缓解标记、标签错位问题,将ATE标签显式注入到句子上下文中,由此经过微调的MALM能够显式地调整标签信息来预测掩码的方面标记。因此,MALM可帮助生成具有新方面的高质量增强数据,提供丰富的层面方面知识。此外,提出了一个两阶段的训练策略来整合这些合成数据。通过实验,证明了MALM在两个ATE数据集上的有效性,相比基线方法,所提出的MALM有显著的性能改进。 展开更多
关键词 数据增强 aspect术语提取 预训练模型 掩码方面语言建模 MALM方法
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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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A Conceptual and Computational Framework for Aspect-Based Collaborative Filtering Recommender Systems 被引量:1
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作者 Samin Poudel Marwan Bikdash 《Journal of Computer and Communications》 2023年第3期110-130,共21页
Many datasets in E-commerce have rich information about items and users who purchase or rate them. This information can enable advanced machine learning algorithms to extract and assign user sentiments to various aspe... Many datasets in E-commerce have rich information about items and users who purchase or rate them. This information can enable advanced machine learning algorithms to extract and assign user sentiments to various aspects of the items thus leading to more sophisticated and justifiable recommendations. However, most Collaborative Filtering (CF) techniques rely mainly on the overall preferences of users toward items only. And there is lack of conceptual and computational framework that enables an understandable aspect-based AI approach to recommending items to users. In this paper, we propose concepts and computational tools that can sharpen the logic of recommendations and that rely on users’ sentiments along various aspects of items. These concepts include: The sentiment of a user towards a specific aspect of a specific item, the emphasis that a given user places on a specific aspect in general, the popularity and controversy of an aspect among groups of users, clusters of users emphasizing a given aspect, clusters of items that are popular among a group of users and so forth. The framework introduced in this study is developed in terms of user emphasis, aspect popularity, aspect controversy, and users and items similarity. Towards this end, we introduce the Aspect-Based Collaborative Filtering Toolbox (ABCFT), where the tools are all developed based on the three-index sentiment tensor with the indices being the user, item, and aspect. The toolbox computes solutions to the questions alluded to above. We illustrate the methodology using a hotel review dataset having around 6000 users, 400 hotels and 6 aspects. 展开更多
关键词 Recommender System Collaborative Filtering aspect based recommendation Recommendation System Framework aspect Sentiments
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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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人工智能在急性缺血性脑卒中早期ASPECTS评估中的研究进展 被引量:3
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作者 方婷 杨一风 +1 位作者 贾守强 聂生东 《中国医学物理学杂志》 CSCD 2023年第8期1045-1050,共6页
急性缺血性脑卒中(AIS)的早期诊断和及时干预对于降低脑卒中的致死致残率具有重要意义。目前,临床上采用阿尔伯塔卒中项目早期计算机断层扫描评分(ASPECTS)来评估AIS的严重程度,但人为评估方法主观性过强且耗时耗力,极易导致漏诊、误诊... 急性缺血性脑卒中(AIS)的早期诊断和及时干预对于降低脑卒中的致死致残率具有重要意义。目前,临床上采用阿尔伯塔卒中项目早期计算机断层扫描评分(ASPECTS)来评估AIS的严重程度,但人为评估方法主观性过强且耗时耗力,极易导致漏诊、误诊。因此,近年来涌现了许多基于人工智能算法对AIS进行ASPECTS自动评分的方法研究。本文对此进行综述,以期为进一步研究探索提供参考。首先,简述ASPECTS评分的可靠性;其次,重点介绍目前基于人工智能的脑区提取及脑区评分的方法,证实计算机辅助ASPECTS评分能够有效提高对病情判断的可靠性;最后,总结现有ASPECTS自动评分方法存在的不足,并对其未来的发展趋势进行展望。 展开更多
关键词 aspectS评分 急性缺血性脑卒中 人工智能 自动化评分 综述
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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:1
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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 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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Multi-Task Learning Model with Data Augmentation for Arabic Aspect-Based Sentiment Analysis
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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-Based Sentiment Analysis for Social Multimedia:A Hybrid Computational Framework
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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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Aspect Level Songs Rating Based Upon Reviews in English
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作者 Muhammad Aasim Qureshi Muhammad Asif +4 位作者 Saira Anwar Umar Shaukat Atta-ur-Rahman Muhammad Adnan Khan Amir Mosavi 《Computers, Materials & Continua》 SCIE EI 2023年第2期2589-2605,共17页
With the advancements in internet facilities,people are more inclined towards the use of online services.The service providers shelve their items for e-users.These users post their feedbacks,reviews,ratings,etc.after ... With the advancements in internet facilities,people are more inclined towards the use of online services.The service providers shelve their items for e-users.These users post their feedbacks,reviews,ratings,etc.after the use of the item.The enormous increase in these reviews has raised the need for an automated system to analyze these reviews to rate these items.Sentiment Analysis(SA)is a technique that performs such decision analysis.This research targets the ranking and rating through sentiment analysis of these reviews,on different aspects.As a case study,Songs are opted to design and test the decision model.Different aspects of songs namely music,lyrics,song,voice and video are picked.For the reason,reviews of 20 songs are scraped from YouTube,pre-processed and formed a dataset.Different machine learning algorithms—Naïve Bayes(NB),Gradient Boost Tree,Logistic Regression LR,K-Nearest Neighbors(KNN)and Artificial Neural Network(ANN)are applied.ANN performed the best with 74.99%accuracy.Results are validated using K-Fold. 展开更多
关键词 Machine learning natural language processing songs reviews:sentiment analysis songs rating aspect level sentiment analysis reviews analysis text classification MUSIC
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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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Influence of quarantine during the coronavirus disease 2019(COVID-19)pandemic on physical and psychosocial aspects:perceptions of 214 Brazilian athletes
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作者 Eliane de Morais Machado Leonardo Luiz Barretti Secchi +1 位作者 Paula Rezende Camargo Luciana De Michelis Mendonca 《Global Health Journal》 2023年第1期49-54,共6页
Background:Social distancing may affect athletes,training,causing negative effects on mental and physical health.Objective:This study therefore aimed to characterize the perception of Brazilian athletes about their ph... Background:Social distancing may affect athletes,training,causing negative effects on mental and physical health.Objective:This study therefore aimed to characterize the perception of Brazilian athletes about their physical and psychosocial aspects,sleep quality and coping strategies during the quarantine of the coronavirus disease 2019(COVID-19)pandemic.Methods:This was a cross-sectional study with online survey,performed with Brazilian athletes(amateur and professional)over 18 years.The main outcomes measures assessed were physical and psychosocial aspects,sleep quality and coping strategies.Results:A total of 214 athletes were included.The average weekly hours of training during the quarantine was 4.71±3.71 h,of which 64.5%athletes(138/214)were oriented by medical staff during training.For 52.8%(113/214)of athletes,training intensity during the quarantine was different/very different from the intensity before the quarantine.79.4%athletes(170/214)reported moderate to extreme difficulties in keeping the same level of training during the quarantine.77.1%athletes(165/214)had moderate to extreme anxiety and each of the athletes had concern about his or her athletic career future,including return to the sport.72.9%athletes(156/214)reported change in sleep schedule during the quarantine period.Conclusion:The quarantine period during COVID-19 pandemic negatively affected the athlete^perception about training routine,since athletes reported reduction in training hours and training intensity.Overall,the athletes reported that they were moderately to extremely anxious.They also had concerns about their career in the future,as well as concerns regarding return to sport. 展开更多
关键词 Social isolation Performance Psychological aspects Sleep quality Sport
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面向Aspect的操作系统研究 被引量:10
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作者 陈向群 杨芙清 《软件学报》 EI CSCD 北大核心 2006年第3期620-627,共8页
面向Aspect软件设计是一种新的软件设计思想和技术.分析了近年来操作系统贯穿特性与Aspect概念,构件重构、系统演化与设计,系统安全、性能检测与容错这3个方面的研究成果,指出面向Aspect操作系统研究已经获得了积极的成果.但是,目前的... 面向Aspect软件设计是一种新的软件设计思想和技术.分析了近年来操作系统贯穿特性与Aspect概念,构件重构、系统演化与设计,系统安全、性能检测与容错这3个方面的研究成果,指出面向Aspect操作系统研究已经获得了积极的成果.但是,目前的研究缺乏一定的深度和广度,尚没有在操作系统的设计阶段运用AOP(Aspect-Orientedoperating)思想的成果出现.在已有操作系统代码中抽象Aspect的过程中,缺乏完整的工程化和规范化的研究.这些问题的解决有赖于面向Aspect研究的进一步深入.最后,对面向Aspect操作系统研究的前景进行展望,认为有关AOSD(Aspect-Orientedsoftwaredevelopment)的研究有可能对未来操作系统的发展产生重大影响. 展开更多
关键词 面向aspect软件设计 面向aspect程序设计 操作系统
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Biermer’s Disease at the Donka National Hospital in Guinea—Epidemio-Clinical, Therapeutic and Evolutionary Aspect in the Internal Medicine Department
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作者 Thierno Amadou Wann Mamadou Sarifou Diallo +6 位作者 Djenabou Diallo Kadiatou Diallo Mamadou Lamine Yaya Bah Mamadou Diakhaby Mohamed Cissoko Amadou Kaké Djibril Sylla 《Open Journal of Internal Medicine》 2023年第3期218-224,共7页
Introduction: Biermer’s disease is an autoimmune disease characterized by a lack of absorption of vitamin B12 in connection with the production of antibodies (A) destroying the intrinsic factor (IF) which allows the ... Introduction: Biermer’s disease is an autoimmune disease characterized by a lack of absorption of vitamin B12 in connection with the production of antibodies (A) destroying the intrinsic factor (IF) which allows the absorption of vitamin B12 (cobalamin). These clinical manifestations are polymorphic and severe in our context. The objective of this work is to identify the epidemiological-clinical, therapeutic and evolutionary characteristics of Biermer’s disease in Guinean population. Materials and methods: This was a retrospective of patient files followed for Biermer’s disease at the internal medicine department of Donka National Hospital from January 2012 to December 2021. Results: Eight patients were included including 5 women and 3 men. The average age of the patients was 48 years old. The diagnostic delay was 3.6 years on average. All our patients had bioclinical anemia (8 cases, i.e. 100%) followed by epigastralgia in 4 cases (50%), neurological damage such as sensitive polyneuropathy in 3 cases (37.5%). Four patients had acquired melanoderma (50%). Hypovitaminosis B12 was found in 4 patients. The myelogram performed in three patients (37.5%) found medullary megaloblastosis. One patient had Hashimoto’s disease associated with Biermer’s disease in endoscopy, (FOGD) found fundica trophy on macroscopy in 4 cases (50%). Treatment consisted of B12 vitamin therapy in all cases with a favorable clinical and biological outcome. Conclusion: Biermer’s disease remains common in Africa and is characterized at a younger age in addition to the severity of clinical and biological manifestations. The care consists of taking vitamin B12 which remains accessible in our context. 展开更多
关键词 Biermer’s Disease Donka aspects Epidemiological-Clinical THERAPEUTICS
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