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Dialogue Relation Extraction Enhanced with Trigger:A Multi-Feature Filtering and Fusion Model
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作者 Haitao Wang Yuanzhao Guo +1 位作者 Xiaotong Han Yuan Tian 《Computers, Materials & Continua》 2025年第4期137-155,共19页
Relation extraction plays a crucial role in numerous downstream tasks.Dialogue relation extraction focuses on identifying relations between two arguments within a given dialogue.To tackle the problem of low informatio... Relation extraction plays a crucial role in numerous downstream tasks.Dialogue relation extraction focuses on identifying relations between two arguments within a given dialogue.To tackle the problem of low information density in dialogues,methods based on trigger enhancement have been proposed,yielding positive results.However,trigger enhancement faces challenges,which cause suboptimal model performance.First,the proportion of annotated triggers is low in DialogRE.Second,feature representations of triggers and arguments often contain conflicting information.In this paper,we propose a novel Multi-Feature Filtering and Fusion trigger enhancement approach to overcome these limitations.We first obtain representations of arguments,and triggers that contain rich semantic information through attention and gate methods.Then,we design a feature filtering mechanism that eliminates conflicting features in the encoding of trigger prototype representations and their corresponding argument pairs.Additionally,we utilize large language models to create prompts based on Chain-of-Thought and In-context Learning for automated trigger extraction.Experiments show that our model increases the average F1 score by 1.3%in the dialogue relation extraction task.Ablation and case studies confirm the effectiveness of our model.Furthermore,the feature filtering method effectively integrates with other trigger enhancement models,enhancing overall performance and demonstrating its ability to resolve feature conflicts. 展开更多
关键词 Dialogue relation extraction feature filtering chain-of-thought
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Ensemble Filter-Wrapper Text Feature Selection Methods for Text Classification 被引量:1
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作者 Oluwaseun Peter Ige Keng Hoon Gan 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第11期1847-1865,共19页
Feature selection is a crucial technique in text classification for improving the efficiency and effectiveness of classifiers or machine learning techniques by reducing the dataset’s dimensionality.This involves elim... Feature selection is a crucial technique in text classification for improving the efficiency and effectiveness of classifiers or machine learning techniques by reducing the dataset’s dimensionality.This involves eliminating irrelevant,redundant,and noisy features to streamline the classification process.Various methods,from single feature selection techniques to ensemble filter-wrapper methods,have been used in the literature.Metaheuristic algorithms have become popular due to their ability to handle optimization complexity and the continuous influx of text documents.Feature selection is inherently multi-objective,balancing the enhancement of feature relevance,accuracy,and the reduction of redundant features.This research presents a two-fold objective for feature selection.The first objective is to identify the top-ranked features using an ensemble of three multi-univariate filter methods:Information Gain(Infogain),Chi-Square(Chi^(2)),and Analysis of Variance(ANOVA).This aims to maximize feature relevance while minimizing redundancy.The second objective involves reducing the number of selected features and increasing accuracy through a hybrid approach combining Artificial Bee Colony(ABC)and Genetic Algorithms(GA).This hybrid method operates in a wrapper framework to identify the most informative subset of text features.Support Vector Machine(SVM)was employed as the performance evaluator for the proposed model,tested on two high-dimensional multiclass datasets.The experimental results demonstrated that the ensemble filter combined with the ABC+GA hybrid approach is a promising solution for text feature selection,offering superior performance compared to other existing feature selection algorithms. 展开更多
关键词 Metaheuristic algorithms text classification multi-univariate filter feature selection ensemble filter-wrapper techniques
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Improved preprocessed Yaroslavsky filter based on shearlet features
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作者 吴一全 戴一冕 吴健生 《Journal of Beijing Institute of Technology》 EI CAS 2016年第1期135-144,共10页
An improved preprocessed Yaroslavsky filter(IPYF)is proposed to avoid the nick effects and obtain a better denoising result when the noise variance is unknown.Different from its predecessors,the similarity between t... An improved preprocessed Yaroslavsky filter(IPYF)is proposed to avoid the nick effects and obtain a better denoising result when the noise variance is unknown.Different from its predecessors,the similarity between two pixels is calculated by shearlet features.The feature vector consists of initial denoised results by the non-subsampled shearlet transform hard thresholding(NSST-HT)and NSST coefficients,which can help allocate the averaging weights more reasonably.With the correct estimated noise variance,the NSST-HT can provide good denoised results as the initial estimation and high-frequency coefficients contribute large weights to preserve textures.In case of the incorrect estimated noise variance,the low-frequency coefficients will mitigate the nick effect in cartoon regions greatly,making the IPYF more robust than the original PYF.Detailed experimental results show that the IPYF is a very competitive method based on a comprehensive consideration involving peak signal to noise ratio(PSNR),computing time,visual quality and method noise. 展开更多
关键词 image processing image denoising preprocessed Yaroslavsky filter shearlet features nick effect
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Algorithm for 3D point cloud steganalysis based on composite operator feature enhancement
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作者 Shuai REN Hao GONG Suya ZHENG 《Frontiers of Information Technology & Electronic Engineering》 2025年第1期62-78,共17页
Three-dimensional (3D) point cloud information hiding algorithms are mainly concentrated in the spatialdomain. Existing spatial domain steganalysis algorithms are subject to more disturbing factors during the analysis... Three-dimensional (3D) point cloud information hiding algorithms are mainly concentrated in the spatialdomain. Existing spatial domain steganalysis algorithms are subject to more disturbing factors during the analysisand detection process, and can only be applied to 3D mesh objects, so there is a lack of steganalysis algorithms for 3Dpoint cloud objects. To change the fact that steganalysis is limited to 3D mesh and eliminate the redundant featuresin the 3D mesh steganalysis feature set, we propose a 3D point cloud steganalysis algorithm based on compositeoperator feature enhancement. First, the 3D point cloud is normalized and smoothed. Second, the feature pointsthat may contain secret information in 3D point clouds and their neighboring points are extracted as the featureenhancement region by the improved 3DHarris-ISS composite operator. Feature enhancement is performed in thefeature enhancement region to form a feature-enhanced 3D point cloud, which highlights the feature points whilesuppressing the interference created by the rest of the vertices. Third, the existing 3D mesh feature set is screenedto reduce the data redundancy of more relevant features, and the newly proposed local neighborhood feature setis added to the screened feature set to form the 3D point cloud steganography feature set POINT72. Finally,the steganographic features are extracted from the enhanced 3D point cloud using the POINT72 feature set, andsteganalysis experiments are carried out. Experimental analysis shows that the algorithm can accurately analyzethe 3D point cloud’s spatial steganography and determine whether the 3D point cloud contains hidden information,so the accuracy of 3D point cloud steganalysis, under the prerequisite of missing edge and face information, is closeto that of the existing 3D mesh steganalysis algorithms. 展开更多
关键词 STEGANALYSIS 3D point cloud feature enhancement feature set filtering
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Applying machine learning approaches to improving the accuracy of breast-tumour diagnosis via fine needle aspiration
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作者 袁前飞 CAI Cong-zhong +1 位作者 XIAO Han-guang LIU Xing-hua 《Journal of Chongqing University》 CAS 2007年第1期1-7,共7页
Diagnosis and treatment of breast cancer have been improved during the last decade; however, breast cancer is still a leading cause of death among women in the whole world. Early detection and accurate diagnosis of th... Diagnosis and treatment of breast cancer have been improved during the last decade; however, breast cancer is still a leading cause of death among women in the whole world. Early detection and accurate diagnosis of this disease has been demonstrated an approach to long survival of the patients. As an attempt to develop a reliable diagnosing method for breast cancer, we integrated support vector machine (SVM), k-nearest neighbor and probabilistic neural network into a complex machine learning approach to detect malignant breast tumour through a set of indicators consisting of age and ten cellular features of fine-needle aspiration of breast which were ranked according to signal-to-noise ratio to identify determinants distinguishing benign breast tumours from malignant ones. The method turned out to significantly improve the diagnosis, with a sensitivity of 94.04%, a specificity of 97.37%, and an overall accuracy up to 96.24% when SVM was adopted with the sigmoid kernel function under 5-fold cross validation. The results suggest that SVM is a promising methodology to be further developed into a practical adjunct implement to help discerning benign and malignant breast tumours and thus reduce the incidence of misdiagnosis. 展开更多
关键词 breast cancer DIAGNOSIS machine learning approach fine needle aspirate feature ranking/filtering
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Boosted cascade of scattered rectangle features for object detection 被引量:2
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作者 ZHANG WeiZe TONG RuoFeng DONG JinXiang 《Science in China(Series F)》 2009年第2期236-243,共8页
This paper presents a variant of Haar-Iike feature used in Viola and Jones detection framework, called scattered rectangle feature, based on the common-component analysis of local region feature. Three common componen... This paper presents a variant of Haar-Iike feature used in Viola and Jones detection framework, called scattered rectangle feature, based on the common-component analysis of local region feature. Three common components, feature filter, feature structure and feature form, are extracted without concerning the details of the studied region features, which cast a new light on region feature design for specific applications and requirements: modifying some component(s) of a feature for an improved one or combining different components of existing features for a new favorable one. Scattered rectangle feature follows the former way, extending the feature structure component of Haar-like feature out of the restriction of the geometry adjacency rule, which results in a richer representation that explores much more orientations other than horizontal, vertical and diagonal, as well as misaligned, detached and non-rectangle shape information that is unreachable to Haar-Iike feature. The training result of the two face detectors in the experiments illustrates the benefits of scattered rectangle feature empirically; the comparison of the ROC curves under a rigid and objective detection criterion on MIT+CMU upright face test set shows that the cascade based on scattered rectangle features outperforms that based on Haar-Iike features. 展开更多
关键词 Haar-like feature feature filter feature structure feature form CASCADE
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Switchable dual-wavelength fiber ring laser featuring twin-core photonic crystal fiber-based filter 被引量:2
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作者 Khurram Karim Qureshi 《Chinese Optics Letters》 SCIE EI CAS CSCD 2014年第2期27-29,共3页
A simple configuration for the generation of a switchable dual-wavelength fiber ring laser is presented.The proposed configuration employs a short twin-core photonic crystal fiber acting as a Mach–Zehnder interferome... A simple configuration for the generation of a switchable dual-wavelength fiber ring laser is presented.The proposed configuration employs a short twin-core photonic crystal fiber acting as a Mach–Zehnder interferometer at room temperature.A polarization controller is further utilized to enable switchable dualwavelength operation. 展开更多
关键词 PCF length Switchable dual-wavelength fiber ring laser featuring twin-core photonic crystal fiber-based filter CORE ring
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