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Stochastic Variational Inference-Based Parallel and Online Supervised Topic Model for Large-Scale Text Processing 被引量:1
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作者 Yang Li Wen-Zhuo Song Bo Yang 《Journal of Computer Science & Technology》 SCIE EI CSCD 2018年第5期1007-1022,共16页
Topic modeling is a mainstream and effective technology to deal with text data, with wide applications in text analysis, natural language, personalized recommendation, computer vision, etc. Among all the known topic m... Topic modeling is a mainstream and effective technology to deal with text data, with wide applications in text analysis, natural language, personalized recommendation, computer vision, etc. Among all the known topic models, supervised Latent Dirichlet Allocation (sLDA) is acknowledged as a popular and competitive supervised topic model. How- ever, the gradual increase of the scale of datasets makes sLDA more and more inefficient and time-consuming, and limits its applications in a very narrow range. To solve it, a parallel online sLDA, named PO-sLDA (Parallel and Online sLDA), is proposed in this study. It uses the stochastic variational inference as the learning method to make the training procedure more rapid and efficient, and a parallel computing mechanism implemented via the MapReduce framework is proposed to promote the capacity of cloud computing and big data processing. The online training capacity supported by PO-sLDA expands the application scope of this approach, making it instrumental for real-life applications with high real-time demand. The validation using two datasets with different sizes shows that the proposed approach has the comparative accuracy as the sLDA and can efficiently accelerate the training procedure. Moreover, its good convergence and online training capacity make it lucrative for the large-scale text data analyzing and processing. 展开更多
关键词 topic modeling large-scale text classification stochastic variational inference cloud computing online learning
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Filter-based iterative learning control for linear large-scale industrial processes 被引量:4
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作者 Xiao'eRUAN JianguoWANG BaiwuWAN 《控制理论与应用(英文版)》 EI 2004年第2期149-154,共6页
In the procedure of the steady-state hierarchical optimization with feedback for large-scale industrial processes, a sequence of set-point changes with different magnitudes is carried out on the optimization layer. To... In the procedure of the steady-state hierarchical optimization with feedback for large-scale industrial processes, a sequence of set-point changes with different magnitudes is carried out on the optimization layer. To improve the dynamic performance of transient response driven by the set-point changes, a filter-based iterative learning control strategy is proposed. In the proposed updating law, a local-symmetric-integral operator is adopted for eliminating the measurement noise of output information,a set of desired trajectories are specified according to the set-point changes sequence, the current control input is iteratively achieved by utilizing smoothed output error to modify its control input at previous iteration, to which the amplified coefficients related to the different magnitudes of set-point changes are introduced. The convergence of the algorithm is conducted by incorporating frequency-domain technique into time-domain analysis. Numerical simulation demonstrates the effectiveness of the proposed strategy, 展开更多
关键词 Iterative learning control large-scale industrial processes Steady-state optimization Dynamic performance
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Literature classification and its applications in condensed matter physics and materials science by natural language processing
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作者 吴思远 朱天念 +5 位作者 涂思佳 肖睿娟 袁洁 吴泉生 李泓 翁红明 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第5期117-123,共7页
The exponential growth of literature is constraining researchers’access to comprehensive information in related fields.While natural language processing(NLP)may offer an effective solution to literature classificatio... The exponential growth of literature is constraining researchers’access to comprehensive information in related fields.While natural language processing(NLP)may offer an effective solution to literature classification,it remains hindered by the lack of labelled dataset.In this article,we introduce a novel method for generating literature classification models through semi-supervised learning,which can generate labelled dataset iteratively with limited human input.We apply this method to train NLP models for classifying literatures related to several research directions,i.e.,battery,superconductor,topological material,and artificial intelligence(AI)in materials science.The trained NLP‘battery’model applied on a larger dataset different from the training and testing dataset can achieve F1 score of 0.738,which indicates the accuracy and reliability of this scheme.Furthermore,our approach demonstrates that even with insufficient data,the not-well-trained model in the first few cycles can identify the relationships among different research fields and facilitate the discovery and understanding of interdisciplinary directions. 展开更多
关键词 natural language processing text mining materials science
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Unlocking the Potential:A Comprehensive Systematic Review of ChatGPT in Natural Language Processing Tasks
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作者 Ebtesam Ahmad Alomari 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第10期43-85,共43页
As Natural Language Processing(NLP)continues to advance,driven by the emergence of sophisticated large language models such as ChatGPT,there has been a notable growth in research activity.This rapid uptake reflects in... As Natural Language Processing(NLP)continues to advance,driven by the emergence of sophisticated large language models such as ChatGPT,there has been a notable growth in research activity.This rapid uptake reflects increasing interest in the field and induces critical inquiries into ChatGPT’s applicability in the NLP domain.This review paper systematically investigates the role of ChatGPT in diverse NLP tasks,including information extraction,Name Entity Recognition(NER),event extraction,relation extraction,Part of Speech(PoS)tagging,text classification,sentiment analysis,emotion recognition and text annotation.The novelty of this work lies in its comprehensive analysis of the existing literature,addressing a critical gap in understanding ChatGPT’s adaptability,limitations,and optimal application.In this paper,we employed a systematic stepwise approach following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses(PRISMA)framework to direct our search process and seek relevant studies.Our review reveals ChatGPT’s significant potential in enhancing various NLP tasks.Its adaptability in information extraction tasks,sentiment analysis,and text classification showcases its ability to comprehend diverse contexts and extract meaningful details.Additionally,ChatGPT’s flexibility in annotation tasks reducesmanual efforts and accelerates the annotation process,making it a valuable asset in NLP development and research.Furthermore,GPT-4 and prompt engineering emerge as a complementary mechanism,empowering users to guide the model and enhance overall accuracy.Despite its promising potential,challenges persist.The performance of ChatGP Tneeds tobe testedusingmore extensivedatasets anddiversedata structures.Subsequently,its limitations in handling domain-specific language and the need for fine-tuning in specific applications highlight the importance of further investigations to address these issues. 展开更多
关键词 Generative AI large languagemodel(LLM) natural language processing(NLP) ChatGPT GPT(generative pretraining transformer) GPT-4 sentiment analysis NER information extraction ANNOTATION text classification
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Research on Text Mining of Syndrome Element Syndrome Differentiation by Natural Language Processing 被引量:5
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作者 DENG Wen-Xiang ZHU Jian-Ping +6 位作者 LI Jing YUAN Zhi-Ying WU Hua-Ying YAO Zhong-Hua ZHANG Yi-Ge ZHANG Wen-An HUANG Hui-Yong 《Digital Chinese Medicine》 2019年第2期61-71,共11页
Objective Natural language processing (NLP) was used to excavate and visualize the core content of syndrome element syndrome differentiation (SESD). Methods The first step was to build a text mining and analysis envir... Objective Natural language processing (NLP) was used to excavate and visualize the core content of syndrome element syndrome differentiation (SESD). Methods The first step was to build a text mining and analysis environment based on Python language, and built a corpus based on the core chapters of SESD. The second step was to digitalize the corpus. The main steps included word segmentation, information cleaning and merging, document-entry matrix, dictionary compilation and information conversion. The third step was to mine and display the internal information of SESD corpus by means of word cloud, keyword extraction and visualization. Results NLP played a positive role in computer recognition and comprehension of SESD. Different chapters had different keywords and weights. Deficiency syndrome elements were an important component of SESD, such as "Qi deficiency""Yang deficiency" and "Yin deficiency". The important syndrome elements of substantiality included "Blood stasis""Qi stagnation", etc. Core syndrome elements were closely related. Conclusions Syndrome differentiation and treatment was the core of SESD. Using NLP to excavate syndromes differentiation could help reveal the internal relationship between syndromes differentiation and provide basis for artificial intelligence to learn syndromes differentiation. 展开更多
关键词 Syndrome element syndrome differentiation (SESD) Natural language processing (NLP) Diagnostics of TCM Artificial intelligence text mining
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Fast Data Processing of a Polarimeter-Interferometer System on J-TEXT
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作者 刘煜锴 高丽 +3 位作者 刘海庆 杨曜 高翔 J-TEXT Team 《Plasma Science and Technology》 SCIE EI CAS CSCD 2016年第12期1143-1147,共5页
A method of fast data processing has been developed to rapidly obtain evolution of the electron density profile for a multichannel polarimeter-interferometer system(POLARIS)on J-TEXT. Compared with the Abel inversio... A method of fast data processing has been developed to rapidly obtain evolution of the electron density profile for a multichannel polarimeter-interferometer system(POLARIS)on J-TEXT. Compared with the Abel inversion method, evolution of the density profile analyzed by this method can quickly offer important information. This method has the advantage of fast calculation speed with the order of ten milliseconds per normal shot and it is capable of processing up to 1 MHz sampled data, which is helpful for studying density sawtooth instability and the disruption between shots. In the duration of a flat-top plasma current of usual ohmic discharges on J-TEXT, shape factor u is ranged from 4 to 5. When the disruption of discharge happens, the density profile becomes peaked and the shape factor u typically decreases to 1. 展开更多
关键词 fast data processing polarimeter-interferometer J-text
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Numerical‐discrete‐scheme‐incorporated recurrent neural network for tasks in natural language processing 被引量:1
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作者 Mei Liu Wendi Luo +3 位作者 Zangtai Cai Xiujuan Du Jiliang Zhang Shuai Li 《CAAI Transactions on Intelligence Technology》 SCIE EI 2023年第4期1415-1424,共10页
A variety of neural networks have been presented to deal with issues in deep learning in the last decades.Despite the prominent success achieved by the neural network,it still lacks theoretical guidance to design an e... A variety of neural networks have been presented to deal with issues in deep learning in the last decades.Despite the prominent success achieved by the neural network,it still lacks theoretical guidance to design an efficient neural network model,and verifying the performance of a model needs excessive resources.Previous research studies have demonstrated that many existing models can be regarded as different numerical discretizations of differential equations.This connection sheds light on designing an effective recurrent neural network(RNN)by resorting to numerical analysis.Simple RNN is regarded as a discretisation of the forward Euler scheme.Considering the limited solution accuracy of the forward Euler methods,a Taylor‐type discrete scheme is presented with lower truncation error and a Taylor‐type RNN(T‐RNN)is designed with its guidance.Extensive experiments are conducted to evaluate its performance on statistical language models and emotion analysis tasks.The noticeable gains obtained by T‐RNN present its superiority and the feasibility of designing the neural network model using numerical methods. 展开更多
关键词 deep learning natural language processing neural network text analysis
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Word Embeddings and Semantic Spaces in Natural Language Processing 被引量:1
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作者 Peter J. Worth 《International Journal of Intelligence Science》 2023年第1期1-21,共21页
One of the critical hurdles, and breakthroughs, in the field of Natural Language Processing (NLP) in the last two decades has been the development of techniques for text representation that solves the so-called curse ... One of the critical hurdles, and breakthroughs, in the field of Natural Language Processing (NLP) in the last two decades has been the development of techniques for text representation that solves the so-called curse of dimensionality, a problem which plagues NLP in general given that the feature set for learning starts as a function of the size of the language in question, upwards of hundreds of thousands of terms typically. As such, much of the research and development in NLP in the last two decades has been in finding and optimizing solutions to this problem, to feature selection in NLP effectively. This paper looks at the development of these various techniques, leveraging a variety of statistical methods which rest on linguistic theories that were advanced in the middle of the last century, namely the distributional hypothesis which suggests that words that are found in similar contexts generally have similar meanings. In this survey paper we look at the development of some of the most popular of these techniques from a mathematical as well as data structure perspective, from Latent Semantic Analysis to Vector Space Models to their more modern variants which are typically referred to as word embeddings. In this review of algoriths such as Word2Vec, GloVe, ELMo and BERT, we explore the idea of semantic spaces more generally beyond applicability to NLP. 展开更多
关键词 Natural Language processing Vector Space Models Semantic Spaces Word Embeddings Representation Learning text Vectorization Machine Learning Deep Learning
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基于BERT和TextCNN的智能制造成熟度评估方法 被引量:1
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作者 张淦 袁堂晓 +1 位作者 汪惠芬 柳林燕 《计算机集成制造系统》 EI CSCD 北大核心 2024年第3期852-863,共12页
随着智能制造2025目标的临近,企业为了解自身能力水平纷纷加入到智能制造成熟度评估的行列中。然而,由于智能制造成熟度评估标准的复杂性,企业缺乏其对行业水平的了解,导致企业贸然申请,浪费自身时间的同时又占用大量评估资源。鉴于此,... 随着智能制造2025目标的临近,企业为了解自身能力水平纷纷加入到智能制造成熟度评估的行列中。然而,由于智能制造成熟度评估标准的复杂性,企业缺乏其对行业水平的了解,导致企业贸然申请,浪费自身时间的同时又占用大量评估资源。鉴于此,设计了一种新的评估流程,采用文本处理算法对整个评估过程进行了重构,通过利用国标文件中智能制造成熟度评估标准,将其作为训练集,采用基于预训练语言模型与文本神经网络(BERT+TextCNN)相结合的智能评估算法代替人工评估。在真实的企业智能制造数据集上的验证表明,当BERT+TextCNN评估模型在卷积核为[2,3,4]、迭代次数为6次、学习率为3e-5时,对智能制造成熟度进行评估,准确率达到85.32%。这表明所设计的评估方法能够较准确地帮助企业完成智能制造成熟度自评估,有助于企业了解自身智能制造能力水平,制定正确的发展方向。 展开更多
关键词 智能制造成熟度模型 BERT预训练语言模型 文本卷积神经网络 评估过程重构
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Key-Value Store Coupled with an Operating System for Storing Large-Scale Values
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作者 Jeonghwan Im Hyuk-Yoon Kwon 《Computers, Materials & Continua》 SCIE EI 2022年第11期3333-3350,共18页
The key-value store can provide flexibility of data types because it does not need to specify the data types to be stored in advance and can store any types of data as the value of the key-value pair.Various types of ... The key-value store can provide flexibility of data types because it does not need to specify the data types to be stored in advance and can store any types of data as the value of the key-value pair.Various types of studies have been conducted to improve the performance of the key-value store while maintaining its flexibility.However,the research efforts storing the large-scale values such as multimedia data files(e.g.,images or videos)in the key-value store were limited.In this study,we propose a new key-value store,WR-Store++aiming to store the large-scale values stably.Specifically,it provides a new design of separating data and index by working with the built-in data structure of the Windows operating system and the file system.The utilization of the built-in data structure of the Windows operating system achieves the efficiency of the key-value store and that of the file system extends the limited space of the storage significantly.We also present chunk-based memory management and parallel processing of WR-Store++to further improve its performance in the GET operation.Through the experiments,we show that WR-Store++can store at least 32.74 times larger datasets than the existing baseline key-value store,WR-Store,which has the limitation in storing large-scale data sets.Furthermore,in terms of processing efficiency,we show that WR-Store++outperforms not only WR-Store but also the other state-ofthe-art key-value stores,LevelDB,RocksDB,and BerkeleyDB,for individual key-value operations and mixed workloads. 展开更多
关键词 Key-value stores large-scale values chunk-based memory management parallel processing
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Natural Language Processing with Optimal Deep Learning Based Fake News Classification
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作者 Sara AAlthubiti Fayadh Alenezi Romany F.Mansour 《Computers, Materials & Continua》 SCIE EI 2022年第11期3529-3544,共16页
The recent advancements made in World Wide Web and social networking have eased the spread of fake news among people at a faster rate.At most of the times,the intention of fake news is to misinform the people and make... The recent advancements made in World Wide Web and social networking have eased the spread of fake news among people at a faster rate.At most of the times,the intention of fake news is to misinform the people and make manipulated societal insights.The spread of low-quality news in social networking sites has a negative influence upon people as well as the society.In order to overcome the ever-increasing dissemination of fake news,automated detection models are developed using Artificial Intelligence(AI)and Machine Learning(ML)methods.The latest advancements in Deep Learning(DL)models and complex Natural Language Processing(NLP)tasks make the former,a significant solution to achieve Fake News Detection(FND).In this background,the current study focuses on design and development of Natural Language Processing with Sea Turtle Foraging Optimizationbased Deep Learning Technique for Fake News Detection and Classification(STODL-FNDC)model.The aim of the proposed STODL-FNDC model is to discriminate fake news from legitimate news in an effectual manner.In the proposed STODL-FNDC model,the input data primarily undergoes pre-processing and Glove-based word embedding.Besides,STODL-FNDC model employs Deep Belief Network(DBN)approach for detection as well as classification of fake news.Finally,STO algorithm is utilized after adjusting the hyperparameters involved in DBN model,in an optimal manner.The novelty of the study lies in the design of STO algorithm with DBN model for FND.In order to improve the detection performance of STODL-FNDC technique,a series of simulations was carried out on benchmark datasets.The experimental outcomes established the better performance of STODL-FNDC approach over other methods with a maximum accuracy of 95.50%. 展开更多
关键词 Natural language processing text mining fake news detection deep belief network machine learning evolutionary algorithm
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Observational Features of Large-Scale Structures as Revealed by the Catastrophe Model of Solar Eruptions
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作者 Jun Lin National Astronomical Observatories/Yunnan Observatory, Chinese Academy of Sciences, Kunming 650011 Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138, USA 《Chinese Journal of Astronomy and Astrophysics》 CSCD 2007年第4期457-476,共20页
Large-scale magnetic structures are the main carrier of major eruptions in the solar atmosphere. These structures are rooted in the photosphere and are driven by the unceasing motion of the photospheric material throu... Large-scale magnetic structures are the main carrier of major eruptions in the solar atmosphere. These structures are rooted in the photosphere and are driven by the unceasing motion of the photospheric material through a series of equilibrium configurations. The motion brings energy into the coronal magnetic field until the system ceases to be in equilibrium. The catastrophe theory for solar eruptions indicates that loss of mechanical equilibrium constitutes the main trigger mechanism of major eruptions, usually shown up as solar flares, eruptive prominences, and coronal mass ejections (CMEs). Magnetic reconnection which takes place at the very beginning of the eruption as a result of plasma instabilities/turbulence inside the current sheet, converts magnetic energy into heating and kinetic energy that are responsible for solar flares, and for accelerating both plasma ejecta (flows and CMEs) and energetic particles. Various manifestations are thus related to one another, and the physics behind these relationships is catastrophe and magnetic reconnection. This work reports on recent progress in both theoretical research and observations on eruptive phenomena showing the above manifestations. We start by displaying the properties of large-scale structures in the corona and the related magnetic fields prior to an eruption, and show various morphological features of the disrupting magnetic fields. Then, in the framework of the catastrophe theory, we look into the physics behind those features investigated in a succession of previous works, and discuss the approaches they used. 展开更多
关键词 Sun: large-scale magnetic structures - Sun: eruptive processes - Sun: theory and observations - magnetic reconnection and current sheets
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Text-to-SQL文本信息处理技术研究综述 被引量:1
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作者 彭钰寒 乔少杰 +5 位作者 薛骐 李江敏 谢添丞 徐康镭 冉黎琼 曾少北 《无线电工程》 2024年第5期1053-1062,共10页
信号与信息处理的需求日益增加,离不开数据处理技术,数据处理需要数据库的支持,然而没有经过训练的使用者会因为不熟悉数据库操作产生诸多问题。文本转结构化查询语言(Text to Structured Query Language,Text-to-SQL)的出现,使用户无... 信号与信息处理的需求日益增加,离不开数据处理技术,数据处理需要数据库的支持,然而没有经过训练的使用者会因为不熟悉数据库操作产生诸多问题。文本转结构化查询语言(Text to Structured Query Language,Text-to-SQL)的出现,使用户无需掌握结构化查询语言(Structured Query Language,SQL)也能够熟练操作数据库。介绍Text-to-SQL的研究背景及面临的挑战;介绍Text-to-SQL关键技术、基准数据集、模型演变及最新研究进展,关键技术包括Transformer等主流技术,用于模型训练的基准数据集包括WikiSQL和Spider;介绍Text-to-SQL不同阶段模型的特点,详细阐述Text-to-SQL最新研究成果的工作原理,包括模型构建、解析器设计及数据集生成;总结Text-to-SQL未来的发展方向及研究重点。 展开更多
关键词 文本转结构化查询语言 解析器 文本信息处理 数据库 深度学习
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Generating Factual Text via Entailment Recognition Task
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作者 Jinqiao Dai Pengsen Cheng Jiayong Liu 《Computers, Materials & Continua》 SCIE EI 2024年第7期547-565,共19页
Generating diverse and factual text is challenging and is receiving increasing attention.By sampling from the latent space,variational autoencoder-based models have recently enhanced the diversity of generated text.Ho... Generating diverse and factual text is challenging and is receiving increasing attention.By sampling from the latent space,variational autoencoder-based models have recently enhanced the diversity of generated text.However,existing research predominantly depends on summarizationmodels to offer paragraph-level semantic information for enhancing factual correctness.The challenge lies in effectively generating factual text using sentence-level variational autoencoder-based models.In this paper,a novel model called fact-aware conditional variational autoencoder is proposed to balance the factual correctness and diversity of generated text.Specifically,our model encodes the input sentences and uses them as facts to build a conditional variational autoencoder network.By training a conditional variational autoencoder network,the model is enabled to generate text based on input facts.Building upon this foundation,the input text is passed to the discriminator along with the generated text.By employing adversarial training,the model is encouraged to generate text that is indistinguishable to the discriminator,thereby enhancing the quality of the generated text.To further improve the factual correctness,inspired by the natural language inference system,the entailment recognition task is introduced to be trained together with the discriminator via multi-task learning.Moreover,based on the entailment recognition results,a penalty term is further proposed to reconstruct the loss of our model,forcing the generator to generate text consistent with the facts.Experimental results demonstrate that compared with competitivemodels,ourmodel has achieved substantial improvements in both the quality and factual correctness of the text,despite only sacrificing a small amount of diversity.Furthermore,when considering a comprehensive evaluation of diversity and quality metrics,our model has also demonstrated the best performance. 展开更多
关键词 text generation entailment recognition task natural language processing artificial intelligence
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Smart Approaches to Efficient Text Mining for Categorizing Sexual Reproductive Health Short Messages into Key Themes
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作者 Tobias Makai Mayumbo Nyirenda 《Open Journal of Applied Sciences》 2024年第2期511-532,共22页
To promote behavioral change among adolescents in Zambia, the National HIV/AIDS/STI/TB Council, in collaboration with UNICEF, developed the Zambia U-Report platform. This platform provides young people with improved a... To promote behavioral change among adolescents in Zambia, the National HIV/AIDS/STI/TB Council, in collaboration with UNICEF, developed the Zambia U-Report platform. This platform provides young people with improved access to information on various Sexual Reproductive Health topics through Short Messaging Service (SMS) messages. Over the years, the platform has accumulated millions of incoming and outgoing messages, which need to be categorized into key thematic areas for better tracking of sexual reproductive health knowledge gaps among young people. The current manual categorization process of these text messages is inefficient and time-consuming and this study aims to automate the process for improved analysis using text-mining techniques. Firstly, the study investigates the current text message categorization process and identifies a list of categories adopted by counselors over time which are then used to build and train a categorization model. Secondly, the study presents a proof of concept tool that automates the categorization of U-report messages into key thematic areas using the developed categorization model. Finally, it compares the performance and effectiveness of the developed proof of concept tool against the manual system. The study used a dataset comprising 206,625 text messages. The current process would take roughly 2.82 years to categorise this dataset whereas the trained SVM model would require only 6.4 minutes while achieving an accuracy of 70.4% demonstrating that the automated method is significantly faster, more scalable, and consistent when compared to the current manual categorization. These advantages make the SVM model a more efficient and effective tool for categorizing large unstructured text datasets. These results and the proof-of-concept tool developed demonstrate the potential for enhancing the efficiency and accuracy of message categorization on the Zambia U-report platform and other similar text messages-based platforms. 展开更多
关键词 Knowledge Discovery in text (KDT) Sexual Reproductive Health (SRH) text Categorization text Classification text Extraction text Mining Feature Extraction Automated Classification process Performance Stemming and Lemmatization Natural Language processing (NLP)
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基于XLNet和多粒度对比学习的新闻主题文本分类方法
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作者 陈敏 王雷春 +2 位作者 徐瑞 史含笑 徐渺 《郑州大学学报(理学版)》 CAS 北大核心 2025年第2期16-23,共8页
新闻主题文本内容简短却含义丰富,传统方法通常只考虑词粒度或句粒度向量中的一种进行研究,未能充分利用新闻主题文本不同粒度向量之间的关联信息。为深入挖掘文本的词向量和句向量间的依赖关系,提出一种基于XLNet和多粒度特征对比学习... 新闻主题文本内容简短却含义丰富,传统方法通常只考虑词粒度或句粒度向量中的一种进行研究,未能充分利用新闻主题文本不同粒度向量之间的关联信息。为深入挖掘文本的词向量和句向量间的依赖关系,提出一种基于XLNet和多粒度特征对比学习的新闻主题分类方法。首先,利用XLNet对新闻主题文本进行特征提取获得文本中词、句粒度的特征表示和潜在空间关系;然后,通过对比学习R-Drop策略生成不同粒度特征的正负样本对,以一定权重对文本的词向量-词向量、词向量-句向量和句向量-句向量进行特征相似度学习,使模型深入挖掘出字符属性和语句属性之间的关联信息,提升模型的表达能力。在THUCNews、Toutiao和SHNews数据集上进行实验,实验结果表明,与基准模型相比,所提方法在准确率和F 1值上都有更好的表现,在三个数据集上的F 1值分别达到了93.88%、90.08%、87.35%,验证了方法的有效性和合理性。 展开更多
关键词 自然语言处理 文本分类 新闻主题 XLNet 对比学习
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Mask Text Detector:一种检测自然场景下任意形状的文本分割网络
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作者 向伟 程博 +3 位作者 杨航 祝来李 武钰智 王雅丽 《西南民族大学学报(自然科学版)》 CAS 2022年第6期660-666,共7页
近年来场景文本检测技术飞速发展,提出一种可适用于任意形状文本检测的新颖算法Mask Text Detector.该算法在Mask R-CNN的基础上,用anchor-free的方法替代了原本的RPN层生成建议框,减少了超参、模型参数和计算量.还提出LQCS(Localizatio... 近年来场景文本检测技术飞速发展,提出一种可适用于任意形状文本检测的新颖算法Mask Text Detector.该算法在Mask R-CNN的基础上,用anchor-free的方法替代了原本的RPN层生成建议框,减少了超参、模型参数和计算量.还提出LQCS(Localization Quality and Classification Score)joint regression,能够将坐标质量和类别分数关联到一起,消除预测阶段不一致的问题.为了让网络区分复杂样本,结合传统的边缘检测算法提出Socle-Mask分支生成分割掩码.该模块在水平和垂直方向上分区别提取纹理特征,并加入通道自注意力机制,让网络自主选择通道特征.我们在三个具有挑战性的数据集(Total-Text、CTW1500和ICDAR2015)中进行了广泛的实验,验证了该算法具有很好的文本检测性能. 展开更多
关键词 目标检测 文本检测 图像处理 分割网络
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Noticeable Focuses in Readinga Text
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作者 李明 《邢台职业技术学院学报》 2007年第4期65-67,共3页
This paper discusses the relationship between commanding those basic information contained in a text and the final purpose of comprehending in a text-reading process.By using the main topic and the central meaning tha... This paper discusses the relationship between commanding those basic information contained in a text and the final purpose of comprehending in a text-reading process.By using the main topic and the central meaning that all texts have as two main examples,the author mainly illustrates what a reader should pay attention to in reading a text. 展开更多
关键词 主要信息 阅读 理解 课文 英语教学
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Main Energy Paths and Energy Cascade Processes of the Two Types of Persistent Heavy Rainfall Events over the Yangtze River–Huaihe River Basin 被引量:6
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作者 Yuanchun ZHANG Jianhua SUN Shenming FU 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2017年第2期129-143,共15页
Two types of persistent heavy rainfall events (PHREs) over the Yangtze River-Huaihe River Basin were determined in a recent statistical study: type A, whose precipitation is mainly located to the south of the Yangt... Two types of persistent heavy rainfall events (PHREs) over the Yangtze River-Huaihe River Basin were determined in a recent statistical study: type A, whose precipitation is mainly located to the south of the Yangtze River; and type B, whose precipitation is mainly located to the north of the river. The present study investigated these two PHRE types using a newly derived set of energy equations to show the scale interaction and main energy paths contributing to the persistence of the precipitation. The main results were as follows. The available potential energy (APE) and kinetic energy (KE) associated with both PHRE types generally increased upward in the troposphere, with the energy of the type-A PHREs stronger than that of the type-B PHREs (except for in the middle troposphere). There were two main common and universal energy paths of the two PHRE types: (1) the baroclinic energy conversion from APE to KE was the dominant energy source for the evolution of large-scale background circulations; and (2) the downscaled energy cascade processes of KE and APE were vital for sustaining the eddy flow, which directly caused the PHREs. The significant differences between the two PHRE types mainly appeared in the lower troposphere, where the baroclinic energy conversion associated with the eddy flow in type-A PHREs was from KE to APE, which reduced the intensity of the precipitation-related eddy flow; whereas, the conversion in type-B PHREs was from APE to KE, which enhanced the eddy flow. 展开更多
关键词 persistent heavy rainfall event energy cascade process large-scale background circulation precipitation-related eddy flow
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Solution-processed perovskite solar cells 被引量:4
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作者 CHANG Jian-hui LIU Kun +3 位作者 LIN Si-yuan YUAN Yong-bo ZHOU Cong-hua YANG Jun-liang 《Journal of Central South University》 SCIE EI CAS CSCD 2020年第4期1104-1133,共30页
Perovskite solar cells(PSCs) have emerged as one of the most promising candidates for photovoltaic applications. Low-cost, low-temperature solution processes including coating and printing techniques makes PSCs promis... Perovskite solar cells(PSCs) have emerged as one of the most promising candidates for photovoltaic applications. Low-cost, low-temperature solution processes including coating and printing techniques makes PSCs promising for the greatly potential commercialization due to the scalability and compatibility with large-scale, roll-to-roll manufacturing processes. In this review, we focus on the solution deposition of charge transport layers and perovskite absorption layer in both mesoporous and planar structural PSC devices. Furthermore, the most recent design strategies via solution deposition are presented as well, which have been explored to enlarge the active area, enhance the crystallization and passivate the defects, leading to the performance improvement of PSC devices. 展开更多
关键词 perovskite solar cells mesoporous structure planar structure solution process large-scale deposition techniques
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