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Weakly Supervised Network with Scribble-Supervised and Edge-Mask for Road Extraction from High-Resolution Remote Sensing Images
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作者 Supeng Yu Fen Huang Chengcheng Fan 《Computers, Materials & Continua》 SCIE EI 2024年第4期549-562,共14页
Significant advancements have been achieved in road surface extraction based on high-resolution remote sensingimage processing. Most current methods rely on fully supervised learning, which necessitates enormous human... Significant advancements have been achieved in road surface extraction based on high-resolution remote sensingimage processing. Most current methods rely on fully supervised learning, which necessitates enormous humaneffort to label the image. Within this field, other research endeavors utilize weakly supervised methods. Theseapproaches aim to reduce the expenses associated with annotation by leveraging sparsely annotated data, such asscribbles. This paper presents a novel technique called a weakly supervised network using scribble-supervised andedge-mask (WSSE-net). This network is a three-branch network architecture, whereby each branch is equippedwith a distinct decoder module dedicated to road extraction tasks. One of the branches is dedicated to generatingedge masks using edge detection algorithms and optimizing road edge details. The other two branches supervise themodel’s training by employing scribble labels and spreading scribble information throughout the image. To addressthe historical flaw that created pseudo-labels that are not updated with network training, we use mixup to blendprediction results dynamically and continually update new pseudo-labels to steer network training. Our solutiondemonstrates efficient operation by simultaneously considering both edge-mask aid and dynamic pseudo-labelsupport. The studies are conducted on three separate road datasets, which consist primarily of high-resolutionremote-sensing satellite photos and drone images. The experimental findings suggest that our methodologyperforms better than advanced scribble-supervised approaches and specific traditional fully supervised methods. 展开更多
关键词 Semantic segmentation road extraction weakly supervised learning scribble supervision remote sensing image
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Relational Turkish Text Classification Using Distant Supervised Entities and Relations
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作者 Halil Ibrahim Okur Kadir Tohma Ahmet Sertbas 《Computers, Materials & Continua》 SCIE EI 2024年第5期2209-2228,共20页
Text classification,by automatically categorizing texts,is one of the foundational elements of natural language processing applications.This study investigates how text classification performance can be improved throu... Text classification,by automatically categorizing texts,is one of the foundational elements of natural language processing applications.This study investigates how text classification performance can be improved through the integration of entity-relation information obtained from the Wikidata(Wikipedia database)database and BERTbased pre-trained Named Entity Recognition(NER)models.Focusing on a significant challenge in the field of natural language processing(NLP),the research evaluates the potential of using entity and relational information to extract deeper meaning from texts.The adopted methodology encompasses a comprehensive approach that includes text preprocessing,entity detection,and the integration of relational information.Experiments conducted on text datasets in both Turkish and English assess the performance of various classification algorithms,such as Support Vector Machine,Logistic Regression,Deep Neural Network,and Convolutional Neural Network.The results indicate that the integration of entity-relation information can significantly enhance algorithmperformance in text classification tasks and offer new perspectives for information extraction and semantic analysis in NLP applications.Contributions of this work include the utilization of distant supervised entity-relation information in Turkish text classification,the development of a Turkish relational text classification approach,and the creation of a relational database.By demonstrating potential performance improvements through the integration of distant supervised entity-relation information into Turkish text classification,this research aims to support the effectiveness of text-based artificial intelligence(AI)tools.Additionally,it makes significant contributions to the development ofmultilingual text classification systems by adding deeper meaning to text content,thereby providing a valuable addition to current NLP studies and setting an important reference point for future research. 展开更多
关键词 Text classification relation extraction NER distant supervision deep learning machine learning
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Local saliency consistency-based label inference for weakly supervised salient object detection using scribble annotations
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作者 Shuo Zhao Peng Cui +1 位作者 Jing Shen Haibo Liu 《CAAI Transactions on Intelligence Technology》 SCIE EI 2024年第1期239-249,共11页
Recently,weak supervision has received growing attention in the field of salient object detection due to the convenience of labelling.However,there is a large performance gap between weakly supervised and fully superv... Recently,weak supervision has received growing attention in the field of salient object detection due to the convenience of labelling.However,there is a large performance gap between weakly supervised and fully supervised salient object detectors because the scribble annotation can only provide very limited foreground/background information.Therefore,an intuitive idea is to infer annotations that cover more complete object and background regions for training.To this end,a label inference strategy is proposed based on the assumption that pixels with similar colours and close positions should have consistent labels.Specifically,k-means clustering algorithm was first performed on both colours and coordinates of original annotations,and then assigned the same labels to points having similar colours with colour cluster centres and near coordinate cluster centres.Next,the same annotations for pixels with similar colours within each kernel neighbourhood was set further.Extensive experiments on six benchmarks demonstrate that our method can significantly improve the performance and achieve the state-of-the-art results. 展开更多
关键词 label inference salient object detection weak supervision
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Reconstruction of lithofacies using a supervised Self-Organizing Map:Application in pseudo-wells based on a synthetic geologic cross-section
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作者 Carreira V.R. Bijani R. Ponte-Neto C.F. 《Artificial Intelligence in Geosciences》 2024年第1期14-26,共13页
Recently,machine learning(ML)has been considered a powerful technological element of different society areas.To transform the computer into a decision maker,several sophisticated methods and algorithms are constantly ... Recently,machine learning(ML)has been considered a powerful technological element of different society areas.To transform the computer into a decision maker,several sophisticated methods and algorithms are constantly created and analyzed.In geophysics,both supervised and unsupervised ML methods have dramatically contributed to the development of seismic and well-log data interpretation.In well-logging,ML algorithms are well-suited for lithologic reconstruction problems,once there is no analytical expressions for computing well-log data produced by a particular rock unit.Additionally,supervised ML methods are strongly dependent on a accurate-labeled training data-set,which is not a simple task to achieve,due to data absences or corruption.Once an adequate supervision is performed,the classification outputs tend to be more accurate than unsupervised methods.This work presents a supervised version of a Self-Organizing Map,named as SSOM,to solve a lithologic reconstruction problem from well-log data.Firstly,we go for a more controlled problem and simulate well-log data directly from an interpreted geologic cross-section.We then define two specific training data-sets composed by density(RHOB),sonic(DT),spontaneous potential(SP)and gamma-ray(GR)logs,all simulated through a Gaussian distribution function per lithology.Once the training data-set is created,we simulate a particular pseudo-well,referred to as classification well,for defining controlled tests.First one comprises a training data-set with no labeled log data of the simulated fault zone.In the second test,we intentionally improve the training data-set with the fault.To bespeak the obtained results for each test,we analyze confusion matrices,logplots,accuracy and precision.Apart from very thin layer misclassifications,the SSOM provides reasonable lithologic reconstructions,especially when the improved training data-set is considered for supervision.The set of numerical experiments shows that our SSOM is extremely well-suited for a supervised lithologic reconstruction,especially to recover lithotypes that are weakly-sampled in the training log-data.On the other hand,some misclassifications are also observed when the cortex could not group the slightly different lithologies. 展开更多
关键词 Self-Organizing Maps supervised machine learning Synthetic well-log data Classification of lithofacies
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Edge-Federated Self-Supervised Communication Optimization Framework Based on Sparsification and Quantization Compression
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作者 Yifei Ding 《Journal of Computer and Communications》 2024年第5期140-150,共11页
The federated self-supervised framework is a distributed machine learning method that combines federated learning and self-supervised learning, which can effectively solve the problem of traditional federated learning... The federated self-supervised framework is a distributed machine learning method that combines federated learning and self-supervised learning, which can effectively solve the problem of traditional federated learning being difficult to process large-scale unlabeled data. The existing federated self-supervision framework has problems with low communication efficiency and high communication delay between clients and central servers. Therefore, we added edge servers to the federated self-supervision framework to reduce the pressure on the central server caused by frequent communication between both ends. A communication compression scheme using gradient quantization and sparsification was proposed to optimize the communication of the entire framework, and the algorithm of the sparse communication compression module was improved. Experiments have proved that the learning rate changes of the improved sparse communication compression module are smoother and more stable. Our communication compression scheme effectively reduced the overall communication overhead. 展开更多
关键词 Communication Optimization Federated Self-Supervision Sparsification Gradient Compression Edge Computing
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Decentralized Semi-Supervised Learning for Stochastic Configuration Networks Based on the Mean Teacher Method
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作者 Kaijing Li Wu Ai 《Journal of Computer and Communications》 2024年第4期247-261,共15页
The aim of this paper is to broaden the application of Stochastic Configuration Network (SCN) in the semi-supervised domain by utilizing common unlabeled data in daily life. It can enhance the classification accuracy ... The aim of this paper is to broaden the application of Stochastic Configuration Network (SCN) in the semi-supervised domain by utilizing common unlabeled data in daily life. It can enhance the classification accuracy of decentralized SCN algorithms while effectively protecting user privacy. To this end, we propose a decentralized semi-supervised learning algorithm for SCN, called DMT-SCN, which introduces teacher and student models by combining the idea of consistency regularization to improve the response speed of model iterations. In order to reduce the possible negative impact of unsupervised data on the model, we purposely change the way of adding noise to the unlabeled data. Simulation results show that the algorithm can effectively utilize unlabeled data to improve the classification accuracy of SCN training and is robust under different ground simulation environments. 展开更多
关键词 Stochastic Neural Network Consistency Regularization Semi-supervised Learning Decentralized Learning
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基于Semi-Supervised LLE的人脸表情识别方法 被引量:1
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作者 冯海亮 黄鸿 +1 位作者 李见为 魏明 《沈阳建筑大学学报(自然科学版)》 EI CAS 2008年第6期1109-1113,共5页
目的为提取有效的鉴别特征和降低鉴别向量的维数来识别人脸表情图像.方法将流行学习(Manifold learning,ML)和半监督学习(Semi-Supervised learning,SSL)结合起来,利用人脸表情图像数据本身的非线性流形结构信息和部分标签信息来调整点... 目的为提取有效的鉴别特征和降低鉴别向量的维数来识别人脸表情图像.方法将流行学习(Manifold learning,ML)和半监督学习(Semi-Supervised learning,SSL)结合起来,利用人脸表情图像数据本身的非线性流形结构信息和部分标签信息来调整点与点之间的距离形成距离矩阵,而后基于被调整的距离矩阵进行线性近邻重建来实现维数约简,提取低维鉴别特征用于人脸表情识别.结果该方法能充分利用数据的结构信息和有限的标签信息,使具有标签信息的同类样本之间的距离最小化,不同类数据之间的距离最大化,进而可以有效地提取数据的低维鉴别子流形,使得分类性能要优于非监督的维数约简方法.结论笔者提出的半监督局部线性嵌入算法能有效地提高人脸表情识别的性能. 展开更多
关键词 流形学习 半监督学习 局部线性嵌入 维数约简 人脸表情识别
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Effects of supervised movie appreciation on the improvement of college students’ life meaning sense 被引量:15
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作者 Xinqiang Wang Dajun Zhang +2 位作者 Jinliang Wang Hui Xu Min Xiao 《Health》 2010年第7期804-810,共7页
The purpose of this study was to explore the effects of supervised movie appreciation on improving the life meaning sense among college students. The intervention combined by “pre-video, post counseling” was conduct... The purpose of this study was to explore the effects of supervised movie appreciation on improving the life meaning sense among college students. The intervention combined by “pre-video, post counseling” was conducted on the experimental group, while the control group received no intervention. Results have shown that the scores on the subscales of will to meaning, life purpose, life control, suffer acceptance and on the total scale have improved significantly. No gender difference was found on the intervention effect, and participants receiving intervention maintained higher level on related subscales a week later, indicating that supervised movie appreciation is an effective way to improve the life meaning sense among college students. 展开更多
关键词 College Students Life MEANING SENSE supervised MOVIE APPRECIATION SUICIDE Prevention MENTAL Health Education
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Supervised descent method for weld pool boundary extraction during fiber laser welding process 被引量:5
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作者 Zhao Yaobang Zhang Dengming +1 位作者 Wu Yuanfeng Yang Changqi 《China Welding》 EI CAS 2019年第1期6-10,共5页
In order to obtain a high-quality weld during the laser welding process, extracting the characteristic parameters of weld pool is an important issue for automated welding. In this paper, the type 304 austenitic stainl... In order to obtain a high-quality weld during the laser welding process, extracting the characteristic parameters of weld pool is an important issue for automated welding. In this paper, the type 304 austenitic stainless steel is welded by a 5 kW high-power fiber laser and a high-speed camera is employed to capture the topside images of weld pools. Then we propose a robust visual-detection approach for the molten pool based on the supervised descent method. It provides an elegant framework for representing the outline of a weld pool and is especially efficient for weld pool detection in the presence of strong uncertainties and disturbances. Finally, welding experimental results verified that the proposed approach can extract the weld pool boundary accurately, which will lay a solid foundation for controlling the weld quality of fiber laser welding process. 展开更多
关键词 fiber laser WELDING MOLTEN POOL supervised DESCENT method BOUNDARY extraction
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Adversarial Learning for Distant Supervised Relation Extraction 被引量:7
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作者 Daojian Zeng Yuan Dai +2 位作者 Feng Li R.Simon Sherratt Jin Wang 《Computers, Materials & Continua》 SCIE EI 2018年第4期121-136,共16页
Recently,many researchers have concentrated on using neural networks to learn features for Distant Supervised Relation Extraction(DSRE).These approaches generally use a softmax classifier with cross-entropy loss,which... Recently,many researchers have concentrated on using neural networks to learn features for Distant Supervised Relation Extraction(DSRE).These approaches generally use a softmax classifier with cross-entropy loss,which inevitably brings the noise of artificial class NA into classification process.To address the shortcoming,the classifier with ranking loss is employed to DSRE.Uniformly randomly selecting a relation or heuristically selecting the highest score among all incorrect relations are two common methods for generating a negative class in the ranking loss function.However,the majority of the generated negative class can be easily discriminated from positive class and will contribute little towards the training.Inspired by Generative Adversarial Networks(GANs),we use a neural network as the negative class generator to assist the training of our desired model,which acts as the discriminator in GANs.Through the alternating optimization of generator and discriminator,the generator is learning to produce more and more discriminable negative classes and the discriminator has to become better as well.This framework is independent of the concrete form of generator and discriminator.In this paper,we use a two layers fully-connected neural network as the generator and the Piecewise Convolutional Neural Networks(PCNNs)as the discriminator.Experiment results show that our proposed GAN-based method is effective and performs better than state-of-the-art methods. 展开更多
关键词 Relation extraction generative adversarial networks distant supervision piecewise convolutional neural networks pair-wise ranking loss
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Human Action Recognition Based on Supervised Class-Specific Dictionary Learning with Deep Convolutional Neural Network Features 被引量:6
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作者 Binjie Gu 《Computers, Materials & Continua》 SCIE EI 2020年第4期243-262,共20页
Human action recognition under complex environment is a challenging work.Recently,sparse representation has achieved excellent results of dealing with human action recognition problem under different conditions.The ma... Human action recognition under complex environment is a challenging work.Recently,sparse representation has achieved excellent results of dealing with human action recognition problem under different conditions.The main idea of sparse representation classification is to construct a general classification scheme where the training samples of each class can be considered as the dictionary to express the query class,and the minimal reconstruction error indicates its corresponding class.However,how to learn a discriminative dictionary is still a difficult work.In this work,we make two contributions.First,we build a new and robust human action recognition framework by combining one modified sparse classification model and deep convolutional neural network(CNN)features.Secondly,we construct a novel classification model which consists of the representation-constrained term and the coefficients incoherence term.Experimental results on benchmark datasets show that our modified model can obtain competitive results in comparison to other state-of-the-art models. 展开更多
关键词 Action recognition deep CNN features sparse model supervised dictionary learning
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Quality of Service Routing Strategy Using Supervised Genetic Algorithm 被引量:4
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作者 王兆霞 孙雨耕 +1 位作者 王志勇 沈花玉 《Transactions of Tianjin University》 EI CAS 2007年第1期48-52,共5页
A supervised genetic algorithm (SGA) is proposed to solve the quality of service (QoS) routing problems in computer networks. The supervised rules of intelligent concept are introduced into genetic algorithms (GAs) to... A supervised genetic algorithm (SGA) is proposed to solve the quality of service (QoS) routing problems in computer networks. The supervised rules of intelligent concept are introduced into genetic algorithms (GAs) to solve the constraint optimization problem. One of the main characteristics of SGA is its searching space can be limited in feasible regions rather than infeasible regions. The superiority of SGA to other GAs lies in that some supervised search rules in which the information comes from the problems are incorporated into SGA. The simulation results show that SGA improves the ability of searching an optimum solution and accelerates the convergent process up to 20 times. 展开更多
关键词 supervised genetic algorithm supervised search rules QoS routing
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Scribble-Supervised Video Object Segmentation 被引量:3
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作者 Peiliang Huang Junwei Han +2 位作者 Nian Liu Jun Ren Dingwen Zhang 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2022年第2期339-353,共15页
Recently,video object segmentation has received great attention in the computer vision community.Most of the existing methods heavily rely on the pixel-wise human annotations,which are expensive and time-consuming to ... Recently,video object segmentation has received great attention in the computer vision community.Most of the existing methods heavily rely on the pixel-wise human annotations,which are expensive and time-consuming to obtain.To tackle this problem,we make an early attempt to achieve video object segmentation with scribble-level supervision,which can alleviate large amounts of human labor for collecting the manual annotation.However,using conventional network architectures and learning objective functions under this scenario cannot work well as the supervision information is highly sparse and incomplete.To address this issue,this paper introduces two novel elements to learn the video object segmentation model.The first one is the scribble attention module,which captures more accurate context information and learns an effective attention map to enhance the contrast between foreground and background.The other one is the scribble-supervised loss,which can optimize the unlabeled pixels and dynamically correct inaccurate segmented areas during the training stage.To evaluate the proposed method,we implement experiments on two video object segmentation benchmark datasets,You Tube-video object segmentation(VOS),and densely annotated video segmentation(DAVIS)-2017.We first generate the scribble annotations from the original per-pixel annotations.Then,we train our model and compare its test performance with the baseline models and other existing works.Extensive experiments demonstrate that the proposed method can work effectively and approach to the methods requiring the dense per-pixel annotations. 展开更多
关键词 Convolutional neural networks(CNNs) SCRIBBLE self-attention video object segmentation weakly supervised
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Renal function and physical fitness after 12-mo supervised training in kidney transplant recipients 被引量:6
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作者 Giulio Sergio Roi Giovanni Mosconi +20 位作者 Valentina Totti Maria Laura Angelini Erica Brugin Patrizio Sarto Laura Merlo Sergio Sgarzi Michele Stancari Paola Todeschini Gaetano La Manna Andrea Ermolao Ferdinando Tripi Lucia Andreoli Gianluigi Sella Alberto Anedda Laura Stefani Giorgio Galanti Rocco Di Michele Franco Merni Manuela Trerotola Daniela Storani Alessandro Nanni Costa 《World Journal of Transplantation》 2018年第1期13-22,共10页
AIM To evaluate the effect of a 12-mo supervised aerobic and resistance training, on renal function and exercise capacity compared to usual care recommendations.METHODS Ninety-nine kidney transplant recipients(KTRs) w... AIM To evaluate the effect of a 12-mo supervised aerobic and resistance training, on renal function and exercise capacity compared to usual care recommendations.METHODS Ninety-nine kidney transplant recipients(KTRs) were assigned to interventional exercise(Group A; n = 52) and a usual care cohort(Group B; n = 47). Blood and urine chemistry, exercise capacity, muscular strength, anthropometric measures and health-related quality of life(HRQo L) were assessed at baseline, and after 6 and 12 mo. Group A underwent a supervised training three times per week for 12 mo. Group B received only general recommendations about home-based physical activities.RESULTS Eighty-five KTRs completed the study(Group A, n = 44; Group B, n = 41). After 12 mo, renal function remained stable in both groups. Group A significantly increased maximum workload(+13 W, P = 0.0003), V'O2 peak(+3.1 mL/kg per minute, P = 0.0099), muscular strength in plantar flexor(+12 kg, P = 0.0368), height in the countermovement jump(+1.9 cm, P = 0.0293) and decreased in Body Mass Index(-0.5 kg/m^2, P = 0.0013). HRQo L significantly improved in physical function(P = 0.0019), physical-role limitations(P = 0.0321) and social functioning scales(P = 0.0346). Noimprovements were found in Group B.CONCLUSION Twelve-month of supervised aerobic and resistance training improves the physiological variables related to physical fitness and cardiovascular risks without consequences on renal function. Recommendations alone are not sufficient to induce changes in exercise capacity of KTRs. Our study is an example of collaborative working between transplant centres, sports medicine and exercise facilities. 展开更多
关键词 KIDNEY TRANSPLANT RECIPIENTS RENAL function supervised EXERCISE AEROBIC EXERCISE Muscle strength
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To supervise or to self‑supervise:a machine learning based comparison on credit supervision 被引量:3
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作者 JoséAmérico Pereira Antunes 《Financial Innovation》 2021年第1期562-582,共21页
This study investigates the need for credit supervision as conducted by on-site banking supervisors.It builds on a real bank on-site credit examination to compare the performance of a hypothetical self-supervision app... This study investigates the need for credit supervision as conducted by on-site banking supervisors.It builds on a real bank on-site credit examination to compare the performance of a hypothetical self-supervision approach,in which banks themselves assess their loan portfolios without external intervention,with the on-site banking supervision approach of the Central Bank of Brazil.The experiment develops two machine learning classification models:the first model is based on good and bad ratings informed by banks,and the second model is based on past on-site credit portfolio examinations conducted by banking supervision.The findings show that the overall performance of the on-site supervision approach is consistently higher than the performance of the self-supervision approach,justifying the need for on-site credit portfolio examination as conducted by the Central Bank. 展开更多
关键词 Bank supervision Machine learning Loan loss provisions On-site credit supervision
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Unsupervised Quick Reduct Algorithm Using Rough Set Theory 被引量:2
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作者 C. Velayutham K. Thangavel 《Journal of Electronic Science and Technology》 CAS 2011年第3期193-201,共9页
Feature selection (FS) is a process to select features which are more informative. It is one of the important steps in knowledge discovery. The problem is that not all features are important. Some of the features ma... Feature selection (FS) is a process to select features which are more informative. It is one of the important steps in knowledge discovery. The problem is that not all features are important. Some of the features may be redundant, and others may be irrelevant and noisy. The conventional supervised FS methods evaluate various feature subsets using an evaluation function or metric to select only those features which are related to the decision classes of the data under consideration. However, for many data mining applications, decision class labels are often unknown or incomplete, thus indicating the significance of unsupervised feature selection. However, in unsupervised learning, decision class labels are not provided. In this paper, we propose a new unsupervised quick reduct (QR) algorithm using rough set theory. The quality of the reduced data is measured by the classification performance and it is evaluated using WEKA classifier tool. The method is compared with existing supervised methods and the result demonstrates the efficiency of the proposed algorithm. 展开更多
关键词 Index Terms--Data mining rough set supervised and unsupervised feature selection unsupervised quick reduct algorithm.
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Lexicalized Dependency Paths Based Supervised Learning for Relation Extraction 被引量:2
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作者 Huiyu Sun Ralph Grishman 《Computer Systems Science & Engineering》 SCIE EI 2022年第12期861-870,共10页
Log-linear models and more recently neural network models used forsupervised relation extraction requires substantial amounts of training data andtime, limiting the portability to new relations and domains. To this en... Log-linear models and more recently neural network models used forsupervised relation extraction requires substantial amounts of training data andtime, limiting the portability to new relations and domains. To this end, we propose a training representation based on the dependency paths between entities in adependency tree which we call lexicalized dependency paths (LDPs). We showthat this representation is fast, efficient and transparent. We further propose representations utilizing entity types and its subtypes to refine our model and alleviatethe data sparsity problem. We apply lexicalized dependency paths to supervisedlearning using the ACE corpus and show that it can achieve similar performancelevel to other state-of-the-art methods and even surpass them on severalcategories. 展开更多
关键词 Relation extraction dependency paths lexicalized dependency paths supervised learning rule-based models
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Physics-constrained indirect supervised learning 被引量:1
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作者 Yuntian Chen Dongxiao Zhang 《Theoretical & Applied Mechanics Letters》 CAS CSCD 2020年第3期155-160,共6页
This study proposes a supervised learning method that does not rely on labels.We use variables associated with the label as indirect labels,and construct an indirect physics-constrained loss based on the physical mech... This study proposes a supervised learning method that does not rely on labels.We use variables associated with the label as indirect labels,and construct an indirect physics-constrained loss based on the physical mechanism to train the model.In the training process,the model prediction is mapped to the space of value that conforms to the physical mechanism through the projection matrix,and then the model is trained based on the indirect labels.The final prediction result of the model conforms to the physical mechanism between indirect label and label,and also meets the constraints of the indirect label.The present study also develops projection matrix normalization and prediction covariance analysis to ensure that the model can be fully trained.Finally,the effect of the physics-constrained indirect supervised learning is verified based on a well log generation problem. 展开更多
关键词 supervised learning Indirect label Physics constrained Physics informed Well logs
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Exploring the Sample Quality Using Rough Sets Theory for the Supervised Classification of Remotely Sensed Imagery 被引量:1
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作者 GE Yong BAI Hexiang +1 位作者 LI Sanping LI Deyu 《Geo-Spatial Information Science》 2008年第2期95-102,共8页
In the supervised classification process of remotely sensed imagery, the quantity of samples is one of the important factors affecting the accuracy of the image classification as well as the keys used to evaluate the ... In the supervised classification process of remotely sensed imagery, the quantity of samples is one of the important factors affecting the accuracy of the image classification as well as the keys used to evaluate the image classification. In general, the samples are acquired on the basis of prior knowledge, experience and higher resolution images. With the same size of samples and the same sampling model, several sets of training sample data can be obtained. In such sets, which set reflects perfect spectral characteristics and ensure the accuracy of the classification can be known only after the accuracy of the classification has been assessed. So, before classification, it would be a meaningful research to measure and assess the quality of samples for guiding and optimizing the consequent classification process. Then, based on the rough set, a new measuring index for the sample quality is proposed. The experiment data is the Landsat TM imagery of the Chinese Yellow River Delta on August 8th, 1999. The experiment compares the Bhattacharrya distance matrices and purity index zl and △x based on rough set theory of 5 sample data and also analyzes its effect on sample quality. 展开更多
关键词 supervised classification measuring the sample quality rough set
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Supervised local and non-local structure preserving projections with application to just-in-time learning for adaptive soft sensor 被引量:4
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作者 邵伟明 田学民 王平 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2015年第12期1925-1934,共10页
In soft sensor field, just-in-time learning(JITL) is an effective approach to model nonlinear and time varying processes. However, most similarity criterions in JITL are computed in the input space only while ignoring... In soft sensor field, just-in-time learning(JITL) is an effective approach to model nonlinear and time varying processes. However, most similarity criterions in JITL are computed in the input space only while ignoring important output information, which may lead to inaccurate construction of relevant sample set. To solve this problem, we propose a novel supervised feature extraction method suitable for the regression problem called supervised local and non-local structure preserving projections(SLNSPP), in which both input and output information can be easily and effectively incorporated through a newly defined similarity index. The SLNSPP can not only retain the virtue of locality preserving projections but also prevent faraway points from nearing after projection,which endues SLNSPP with powerful discriminating ability. Such two good properties of SLNSPP are desirable for JITL as they are expected to enhance the accuracy of similar sample selection. Consequently, we present a SLNSPP-JITL framework for developing adaptive soft sensor, including a sparse learning strategy to limit the scale and update the frequency of database. Finally, two case studies are conducted with benchmark datasets to evaluate the performance of the proposed schemes. The results demonstrate the effectiveness of LNSPP and SLNSPP. 展开更多
关键词 Adaptive soft sensor Just-in-time learning supervised local and non-local structure preserving projections Locality preserving projections Database monitoring
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