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船海学术语篇摘要中名词词组形式表征的认知分析——以“Classifier +Thing”为例
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作者 田苗 张宇新 《山东外语教学》 北大核心 2025年第3期19-29,共11页
“Classifier+Thing”结构在船海学术语篇摘要中俯拾皆是,其认知路径和理据亟待深入探究。本研究聚焦“Classifier+Thing”名词词组,分析船海学术语篇摘要中该词组的认知路径及理据。研究发现:(1)“Classifier+Thing”在概念结构-语义... “Classifier+Thing”结构在船海学术语篇摘要中俯拾皆是,其认知路径和理据亟待深入探究。本研究聚焦“Classifier+Thing”名词词组,分析船海学术语篇摘要中该词组的认知路径及理据。研究发现:(1)“Classifier+Thing”在概念结构-语义层的认知过程体现了语法转喻机制,船海摘要语料库中主要通过“过程-动作”“过程-结果”“用途-结构”实现概念结构-语义间的动、静态转换;(2)“Classifier+Thing”的形式表征过程为先确定“核心词(Thing)”,后在大脑词库中匹配“类别语(Classifier)”,遵循认知经济性原则;(3)该词组形式表征过程受学术语篇类型影响,遵循受限语言说。研究结果一定程度上深化了对学术语篇中名词词组的认识,提升学界对于船海学科学术话语的关注。 展开更多
关键词 classifier+Thing” 认知路径及理据 学术摘要 名词词组
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Multi-Class Support Vector Machine Classifier Based on Jeffries-Matusita Distance and Directed Acyclic Graph 被引量:1
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作者 Miao Zhang Zhen-Zhou Lai +1 位作者 Dan Li Yi Shen 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2013年第5期113-118,共6页
Based on the framework of support vector machines (SVM) using one-against-one (OAO) strategy, a new multi-class kernel method based on directed aeyclie graph (DAG) and probabilistic distance is proposed to raise... Based on the framework of support vector machines (SVM) using one-against-one (OAO) strategy, a new multi-class kernel method based on directed aeyclie graph (DAG) and probabilistic distance is proposed to raise the multi-class classification accuracies. The topology structure of DAG is constructed by rearranging the nodes' sequence in the graph. DAG is equivalent to guided operating SVM on a list, and the classification performance depends on the nodes' sequence in the graph. Jeffries-Matusita distance (JMD) is introduced to estimate the separability of each class, and the implementation list is initialized with all classes organized according to certain sequence in the list. To testify the effectiveness of the proposed method, numerical analysis is conducted on UCI data and hyperspectral data. Meanwhile, comparative studies using standard OAO and DAG classification methods are also conducted and the results illustrate better performance and higher accuracy of the orooosed JMD-DAG method. 展开更多
关键词 multi-class classification support vector machine directed acyclic graph Jeffries-Matusitadistance hyperspcctral data
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Drone-Based Public Surveillance Using 3D Point Clouds and Neuro-Fuzzy Classifier
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作者 Yawar Abbas Aisha Ahmed Alarfaj +3 位作者 Ebtisam Abdullah Alabdulqader Asaad Algarni Ahmad Jalal Hui Liu 《Computers, Materials & Continua》 2025年第3期4759-4776,共18页
Human Activity Recognition(HAR)in drone-captured videos has become popular because of the interest in various fields such as video surveillance,sports analysis,and human-robot interaction.However,recognizing actions f... Human Activity Recognition(HAR)in drone-captured videos has become popular because of the interest in various fields such as video surveillance,sports analysis,and human-robot interaction.However,recognizing actions from such videos poses the following challenges:variations of human motion,the complexity of backdrops,motion blurs,occlusions,and restricted camera angles.This research presents a human activity recognition system to address these challenges by working with drones’red-green-blue(RGB)videos.The first step in the proposed system involves partitioning videos into frames and then using bilateral filtering to improve the quality of object foregrounds while reducing background interference before converting from RGB to grayscale images.The YOLO(You Only Look Once)algorithm detects and extracts humans from each frame,obtaining their skeletons for further processing.The joint angles,displacement and velocity,histogram of oriented gradients(HOG),3D points,and geodesic Distance are included.These features are optimized using Quadratic Discriminant Analysis(QDA)and utilized in a Neuro-Fuzzy Classifier(NFC)for activity classification.Real-world evaluations on the Drone-Action,Unmanned Aerial Vehicle(UAV)-Gesture,and Okutama-Action datasets substantiate the proposed system’s superiority in accuracy rates over existing methods.In particular,the system obtains recognition rates of 93%for drone action,97%for UAV gestures,and 81%for Okutama-action,demonstrating the system’s reliability and ability to learn human activity from drone videos. 展开更多
关键词 Activity recognition geodesic distance pattern recognition neuro fuzzy classifier
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A dual-approach to genomic predictions:leveraging convolutional networks and voting classifiers
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作者 Raghad K.Mohammed Azmi Tawfeq Hussein Alrawi Ali Jbaeer Dawood 《Biomedical Engineering Communications》 2025年第1期3-11,共9页
Background:In the field of genetic diagnostics,DNA sequencing is an important tool because the depth and complexity of this field have major implications in light of the genetic architectures of diseases and the ident... Background:In the field of genetic diagnostics,DNA sequencing is an important tool because the depth and complexity of this field have major implications in light of the genetic architectures of diseases and the identification of risk factors associated with genetic disorders.Methods:Our study introduces a novel two-tiered analytical framework to raise the precision and reliability of genetic data interpretation.It is initiated by extracting and analyzing salient features from DNA sequences through a CNN-based feature analysis,taking advantage of the power inherent in Convolutional neural networks(CNNs)to attain complex patterns and minute mutations in genetic data.This study embraces an elite collection of machine learning classifiers interweaved through a stern voting mechanism,which synergistically joins the predictions made from multiple classifiers to generate comprehensive and well-balanced interpretations of the genetic data.Results:This state-of-the-art method was further tested by carrying out an empirical analysis on a variants'dataset of DNA sequences taken from patients affected by breast cancer,juxtaposed with a control group composed of healthy people.Thus,the integration of CNNs with a voting-based ensemble of classifiers returned outstanding outcomes,with performance metrics accuracy,precision,recall,and F1-scorereaching the outstanding rate of 0.88,outperforming previous models.Conclusions:This dual accomplishment underlines the transformative potential that integrating deep learning techniques with ensemble machine learning might provide in real added value for further genetic diagnostics and prognostics.These results from this study set a new benchmark in the accuracy of disease diagnosis through DNA sequencing and promise future studies on improved personalized medicine and healthcare approaches with precise genetic information. 展开更多
关键词 CNN DNA sequencing ensemble machine learning genetic disease voting classifier
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Enhancing Multi-Class Cyberbullying Classification with Hybrid Feature Extraction and Transformer-Based Models
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作者 Suliman Mohamed Fati Mohammed A.Mahdi +4 位作者 Mohamed A.G.Hazber Shahanawaj Ahamad Sawsan A.Saad Mohammed Gamal Ragab Mohammed Al-Shalabi 《Computer Modeling in Engineering & Sciences》 2025年第5期2109-2131,共23页
Cyberbullying on social media poses significant psychological risks,yet most detection systems over-simplify the task by focusing on binary classification,ignoring nuanced categories like passive-aggressive remarks or... Cyberbullying on social media poses significant psychological risks,yet most detection systems over-simplify the task by focusing on binary classification,ignoring nuanced categories like passive-aggressive remarks or indirect slurs.To address this gap,we propose a hybrid framework combining Term Frequency-Inverse Document Frequency(TF-IDF),word-to-vector(Word2Vec),and Bidirectional Encoder Representations from Transformers(BERT)based models for multi-class cyberbullying detection.Our approach integrates TF-IDF for lexical specificity and Word2Vec for semantic relationships,fused with BERT’s contextual embeddings to capture syntactic and semantic complexities.We evaluate the framework on a publicly available dataset of 47,000 annotated social media posts across five cyberbullying categories:age,ethnicity,gender,religion,and indirect aggression.Among BERT variants tested,BERT Base Un-Cased achieved the highest performance with 93%accuracy(standard deviation across±1%5-fold cross-validation)and an average AUC of 0.96,outperforming standalone TF-IDF(78%)and Word2Vec(82%)models.Notably,it achieved near-perfect AUC scores(0.99)for age and ethnicity-based bullying.A comparative analysis with state-of-the-art benchmarks,including Generative Pre-trained Transformer 2(GPT-2)and Text-to-Text Transfer Transformer(T5)models highlights BERT’s superiority in handling ambiguous language.This work advances cyberbullying detection by demonstrating how hybrid feature extraction and transformer models improve multi-class classification,offering a scalable solution for moderating nuanced harmful content. 展开更多
关键词 Cyberbullying classification multi-class classification BERT models machine learning TF-IDF Word2Vec social media analysis transformer models
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RankXLAN:An explainable ensemble-based machine learning framework for biomarker detection,therapeutic target identification,and classification using transcriptomic and epigenomic stomach cancer data
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作者 Kasmika Borah Himanish Shekhar Das +1 位作者 Mudassir Khan Saurav Mallik 《Medical Data Mining》 2026年第1期13-31,共19页
Background:Stomach cancer(SC)is one of the most lethal malignancies worldwide due to late-stage diagnosis and limited treatment.The transcriptomic,epigenomic,and proteomic,etc.,omics datasets generated by high-through... Background:Stomach cancer(SC)is one of the most lethal malignancies worldwide due to late-stage diagnosis and limited treatment.The transcriptomic,epigenomic,and proteomic,etc.,omics datasets generated by high-throughput sequencing technology have become prominent in biomedical research,and they reveal molecular aspects of cancer diagnosis and therapy.Despite the development of advanced sequencing technology,the presence of high-dimensionality in multi-omics data makes it challenging to interpret the data.Methods:In this study,we introduce RankXLAN,an explainable ensemble-based multi-omics framework that integrates feature selection(FS),ensemble learning,bioinformatics,and in-silico validation for robust biomarker detection,potential therapeutic drug-repurposing candidates’identification,and classification of SC.To enhance the interpretability of the model,we incorporated explainable artificial intelligence(SHapley Additive exPlanations analysis),as well as accuracy,precision,F1-score,recall,cross-validation,specificity,likelihood ratio(LR)+,LR−,and Youden index results.Results:The experimental results showed that the top four FS algorithms achieved improved results when applied to the ensemble learning classification model.The proposed ensemble model produced an area under the curve(AUC)score of 0.994 for gene expression,0.97 for methylation,and 0.96 for miRNA expression data.Through the integration of bioinformatics and ML approach of the transcriptomic and epigenomic multi-omics dataset,we identified potential marker genes,namely,UBE2D2,HPCAL4,IGHA1,DPT,and FN3K.In-silico molecular docking revealed a strong binding affinity between ANKRD13C and the FDA-approved drug Everolimus(binding affinity−10.1 kcal/mol),identifying ANKRD13C as a potential therapeutic drug-repurposing target for SC.Conclusion:The proposed framework RankXLAN outperforms other existing frameworks for serum biomarker identification,therapeutic target identification,and SC classification with multi-omics datasets. 展开更多
关键词 stomach cancer BIOINFORMATICS ensemble learning classifier BIOMARKER targets
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A Multi-Classifier Based Prediction Model for Phishing Emails Detection Using Topic Modelling, Named Entity Recognition and Image Processing
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作者 C. Emilin Shyni S. Sarju S. Swamynathan 《Circuits and Systems》 2016年第9期2507-2520,共14页
Phishing is the act of attempting to steal a user’s financial and personal information, such as credit card numbers and passwords by pretending to be a trustworthy participant, during online communication. Attackers ... Phishing is the act of attempting to steal a user’s financial and personal information, such as credit card numbers and passwords by pretending to be a trustworthy participant, during online communication. Attackers may direct the users to a fake website that could seem legitimate, and then gather useful and confidential information using that site. In order to protect users from Social Engineering techniques such as phishing, various measures have been developed, including improvement of Technical Security. In this paper, we propose a new technique, namely, “A Prediction Model for the Detection of Phishing e-mails using Topic Modelling, Named Entity Recognition and Image Processing”. The features extracted are Topic Modelling features, Named Entity features and Structural features. A multi-classifier prediction model is used to detect the phishing mails. Experimental results show that the multi-classification technique outperforms the single-classifier-based prediction techniques. The resultant accuracy of the detection of phishing e-mail is 99% with the highest False Positive Rate being 2.1%. 展开更多
关键词 PHISHING Conditional Random Field classifier Latent Dirichlet Allocation Natural Language Processing Machine Learning Image Segmentation Image Processing
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A Novel Multi-classifier Integrated Model for Chinese Noun Sense Disambiguation
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作者 Jianyong Duan Yi Hu Weilin Wu Hui Liu Ruzhan Lu 《通讯和计算机(中英文版)》 2006年第5期8-13,共6页
关键词 语言程序 中国 自然语言处理 计算机语言
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Knowledge discovery method for feature-decision level fusion of multiple classifiers 被引量:1
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作者 孙亮 韩崇昭 《Journal of Southeast University(English Edition)》 EI CAS 2006年第2期222-227,共6页
To improve the performance of the multiple classifier system, a new method of feature-decision level fusion is proposed based on knowledge discovery. In the new method, the base classifiers operate on different featur... To improve the performance of the multiple classifier system, a new method of feature-decision level fusion is proposed based on knowledge discovery. In the new method, the base classifiers operate on different feature spaces and their types depend on different measures of between-class separability. The uncertainty measures corresponding to each output of each base classifier are induced from the established decision tables (DTs) in the form of mass function in the Dempster-Shafer theory (DST). Furthermore, an effective fusion framework is built at the feature-decision level on the basis of a generalized rough set model and the DST. The experiment for the classification of hyperspectral remote sensing images shows that the performance of the classification can be improved by the proposed method compared with that of plurality voting (PV). 展开更多
关键词 multiple classifier fusion knowledge discovery Dempster-Shafer theory generalized rough set HYPERSPECTRAL
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Naive Bayesian Classifier在遥感影像分类中的应用研究 被引量:4
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作者 陶建斌 舒宁 沈照庆 《遥感信息》 CSCD 2009年第2期52-56,共5页
将Naive Bayesian Classifier(简单贝叶斯网络分类器)用于遥感影像的分类,并对其主要问题如特征选择和后验概率推理等展开研究。使用K2结构学习算法选出具有类别可分性的波段,进一步利用互信息测试对遥感波段之间的相关性做分析,去除冗... 将Naive Bayesian Classifier(简单贝叶斯网络分类器)用于遥感影像的分类,并对其主要问题如特征选择和后验概率推理等展开研究。使用K2结构学习算法选出具有类别可分性的波段,进一步利用互信息测试对遥感波段之间的相关性做分析,去除冗余信息。特征(波段)的条件独立性假设简化了联合概率的计算,以较小的计算代价获得后验概率。在此基础上,将Naive Bayesian Classifier用于多光谱和高光谱影像的分类,获得很好的性能和相当高的稳健性。 展开更多
关键词 贝叶斯网络 简单贝叶斯网络分类器 互信息 条件独立性假设 遥感影像 分类
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Effect of rotor cage rotary speed on classification accuracy in turbo air classifier 被引量:13
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作者 高利苹 于源 刘家祥 《化工学报》 EI CAS CSCD 北大核心 2012年第4期1056-1062,共7页
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Dynamic weighted voting for multiple classifier fusion:a generalized rough set method 被引量:9
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作者 Sun Liang Han Chongzhao 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2006年第3期487-494,共8页
To improve the performance of multiple classifier system, a knowledge discovery based dynamic weighted voting (KD-DWV) is proposed based on knowledge discovery. In the method, all base classifiers may be allowed to ... To improve the performance of multiple classifier system, a knowledge discovery based dynamic weighted voting (KD-DWV) is proposed based on knowledge discovery. In the method, all base classifiers may be allowed to operate in different measurement/feature spaces to make the most of diverse classification information. The weights assigned to each output of a base classifier are estimated by the separability of training sample sets in relevant feature space. For this purpose, some decision tables (DTs) are established in terms of the diverse feature sets. And then the uncertainty measures of the separability are induced, in the form of mass functions in Dempster-Shafer theory (DST), from each DTs based on generalized rough set model. From the mass functions, all the weights are calculated by a modified heuristic fusion function and assigned dynamically to each classifier varying with its output. The comparison experiment is performed on the hyperspectral remote sensing images. And the experimental results show that the performance of the classification can be improved by using the proposed method compared with the plurality voting (PV). 展开更多
关键词 multiple classifier fusion dynamic weighted voting generalized rough set hyperspectral.
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Multi-Class Classification Methods of Cost-Conscious LS-SVM for Fault Diagnosis of Blast Furnace 被引量:15
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作者 LIU Li-mei WANG An-na SHA Mo ZHAO Feng-yun 《Journal of Iron and Steel Research International》 SCIE EI CAS CSCD 2011年第10期17-23,33,共8页
Aiming at the limitations of rapid fault diagnosis of blast furnace, a novel strategy based on cost-conscious least squares support vector machine (LS-SVM) is proposed to solve this problem. Firstly, modified discre... Aiming at the limitations of rapid fault diagnosis of blast furnace, a novel strategy based on cost-conscious least squares support vector machine (LS-SVM) is proposed to solve this problem. Firstly, modified discrete particle swarm optimization is applied to optimize the feature selection and the LS-SVM parameters. Secondly, cost-con- scious formula is presented for fitness function and it contains in detail training time, recognition accuracy and the feature selection. The CLS-SVM algorithm is presented to increase the performance of the LS-SVM classifier. The new method can select the best fault features in much shorter time and have fewer support vectbrs and better general- ization performance in the application of fault diagnosis of the blast furnace. Thirdly, a gradual change binary tree is established for blast furnace faults diagnosis. It is a multi-class classification method based on center-of-gravity formula distance of cluster. A gradual change classification percentage ia used to select sample randomly. The proposed new metbod raises the sped of diagnosis, optimizes the classifieation scraraey and has good generalization ability for fault diagnosis of the application of blast furnace. 展开更多
关键词 blast furnace fault diagnosis eosc-conscious LS-SVM multi-class classification
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Face Recognition Based on Support Vector Machine and Nearest Neighbor Classifier 被引量:8
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作者 Zhang Yankun & Liu Chongqing Institute of Image Processing and Pattern Recognition, Shanghai Jiao long University, Shanghai 200030 P.R.China 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2003年第3期73-76,共4页
Support vector machine (SVM), as a novel approach in pattern recognition, has demonstrated a success in face detection and face recognition. In this paper, a face recognition approach based on the SVM classifier with ... Support vector machine (SVM), as a novel approach in pattern recognition, has demonstrated a success in face detection and face recognition. In this paper, a face recognition approach based on the SVM classifier with the nearest neighbor classifier (NNC) is proposed. The principal component analysis (PCA) is used to reduce the dimension and extract features. Then one-against-all stratedy is used to train the SVM classifiers. At the testing stage, we propose an al- 展开更多
关键词 Face recognition Support vector machine Nearest neighbor classifier Principal component analysis.
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Double-layer Bayesian Classifier Ensembles Based on Frequent Itemsets 被引量:2
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作者 Wei-Guo Yi Jing Duan Ming-Yu Lu 《International Journal of Automation and computing》 EI 2012年第2期215-220,共6页
Numerous models have been proposed to reduce the classification error of Naive Bayes by weakening its attribute independence assumption and some have demonstrated remarkable error performance. Considering that ensembl... Numerous models have been proposed to reduce the classification error of Naive Bayes by weakening its attribute independence assumption and some have demonstrated remarkable error performance. Considering that ensemble learning is an effective method of reducing the classifmation error of the classifier, this paper proposes a double-layer Bayesian classifier ensembles (DLBCE) algorithm based on frequent itemsets. DLBCE constructs a double-layer Bayesian classifier (DLBC) for each frequent itemset the new instance contained and finally ensembles all the classifiers by assigning different weight to different classifier according to the conditional mutual information. The experimental results show that the proposed algorithm outperforms other outstanding algorithms. 展开更多
关键词 Double-layer Bayesian classifier frequent itemsets conditional mutual information support.
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Research on Remote Sensing Image of Land Cover Classification Based on Multiple Classifier Combination 被引量:2
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作者 DAI Lijun LIU Chuang 《Wuhan University Journal of Natural Sciences》 CAS 2011年第4期363-368,共6页
This paper proposed an algorithm in which the maximum probability and the weighted average strategy were used for the combination of member classifiers. Using parallel computing, we test the algorithm on a China-Brazi... This paper proposed an algorithm in which the maximum probability and the weighted average strategy were used for the combination of member classifiers. Using parallel computing, we test the algorithm on a China-Brazil Earth Resources Satellite (CBERS) image for land cover classification. The results show that using three computers in parallel can reduce the classification time by 30%, as compared with using only one computer with a dual core processor. The accuracy of the final image is 93.34%, and Kappa is 0.92. Multiple classifier combination can enhance the precision of the image classification, and parallel computing can increase the speed of calculation so that it becomes possible to process remote sensing images with high efficiency and accuracy. 展开更多
关键词 multiple classifier combination classifiCATION parallel computing
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SDN-based intrusion detection system for IoT using deep learning classifier (IDSIoT-SDL) 被引量:4
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作者 Azka Wani Revathi S Rubeena Khaliq 《CAAI Transactions on Intelligence Technology》 EI 2021年第3期281-290,共10页
The participation of ordinary devices in networking has created a world of connected devices rapidly.The Internet of Things(IoT)includes heterogeneous devices from every field.There are no definite protocols or standa... The participation of ordinary devices in networking has created a world of connected devices rapidly.The Internet of Things(IoT)includes heterogeneous devices from every field.There are no definite protocols or standards for IoT communication,and most of the IoT devices have limited resources.Enabling a complete security measure for such devices is a challenging task,yet necessary.Many lightweight security solutions have surfaced lately for IoT.The lightweight security protocols are unable to provide an optimum protection against prevailing powerful threats in cyber world.It is also hard to deploy any traditional security protocol on resource-constrained IoT devices.Software-defined networking introduces a centralized control in computer networks.SDN has a programmable approach towards networking that decouples control and data planes.An SDN-based intrusion detection system is proposed which uses deep learning classifier for detection of anomalies in IoT.The proposed intrusion detection system does not burden the IoT devices with security profiles.The proposed work is executed on the simulated environment.The results of the simulation test are evaluated using various matrices and compared with other relevant methods. 展开更多
关键词 IOT classifier system
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Mapping of cropland,cropping patterns and crop types by combining optical remote sensing images with decision tree classifier and random forest 被引量:8
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作者 Aqil Tariq Jianguo Yan +2 位作者 Alexandre S.Gagnon Mobushir Riaz Khan Faisal Mumtaz 《Geo-Spatial Information Science》 SCIE EI CSCD 2023年第3期302-320,共19页
Mapping and monitoring the distribution of croplands and crop types support policymakers and international organizations by reducing the risks to food security,notably from climate change and,for that purpose,remote s... Mapping and monitoring the distribution of croplands and crop types support policymakers and international organizations by reducing the risks to food security,notably from climate change and,for that purpose,remote sensing is routinely used.However,identifying specific crop types,cropland,and cropping patterns using space-based observations is challenging because different crop types and cropping patterns have similarity spectral signatures.This study applied a methodology to identify cropland and specific crop types,including tobacco,wheat,barley,and gram,as well as the following cropping patterns:wheat-tobacco,wheat-gram,wheat-barley,and wheat-maize,which are common in Gujranwala District,Pakistan,the study region.The methodology consists of combining optical remote sensing images from Sentinel-2 and Landsat-8 with Machine Learning(ML)methods,namely a Decision Tree Classifier(DTC)and a Random Forest(RF)algorithm.The best time-periods for differentiating cropland from other land cover types were identified,and then Sentinel-2 and Landsat 8 NDVI-based time-series were linked to phenological parameters to determine the different crop types and cropping patterns over the study region using their temporal indices and ML algorithms.The methodology was subsequently evaluated using Landsat images,crop statistical data for 2020 and 2021,and field data on cropping patterns.The results highlight the high level of accuracy of the methodological approach presented using Sentinel-2 and Landsat-8 images,together with ML techniques,for mapping not only the distribution of cropland,but also crop types and cropping patterns when validated at the county level.These results reveal that this methodology has benefits for monitoring and evaluating food security in Pakistan,adding to the evidence base of other studies on the use of remote sensing to identify crop types and cropping patterns in other countries. 展开更多
关键词 Sentinel-2 Random Forest CROPLAND crop types cropping patterns Decision Tree classifier
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Flow Field Characteristics of the Rotor Cage in Turbo Air Classifiers 被引量:2
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作者 GUO Lijie LIU Jiaxiang LIU Shengzhao 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2009年第3期426-432,共7页
The turbo air classifier is widely used powder classification equipment in a variety of fields. The flow field characteristics of the turbo air classifier are important basis for the improvement of the turbo air class... The turbo air classifier is widely used powder classification equipment in a variety of fields. The flow field characteristics of the turbo air classifier are important basis for the improvement of the turbo air classifier's structural design. The flow field characteristics of the rotor cage in turbo air classifiers were investigated trader different operating conditions by laser Doppler velocimeter(LDV), and a measure diminishing the axial velocity is proposed. The investigation results show that the tangential velocity of the air flow inside the rotor cage is different from the rotary speed of the rotor cage on the same measurement point due to the influences of both the negative pressure at the exit and the rotation of the rotor cage. The tangential velocity of the air flow likewise decreases as the radius decreases in the case of the rotor cage's low rotary speed. In contrast, the tangential velocity of the air flow increases as the radius decreases in the case of the rotor cage's high rotary speed. Meanwhile, the vortex inside the rotor cage is found to occur near the pressure side of the blade when the rotor cage's rotary speed is less than the tangential velocity of air flow. On the contrary, the vortex is found to occur near the blade suction side once the rotor cage's rotary speed is higher than the tangential velocity of air flow. Inside the rotor cage, the axial velocity could not be disregarded and is largely determined by the distances between the measurement point and the exit. 展开更多
关键词 turbo air classifier rotor cage flow field characteristic laser Doppler velocimeter(LDV)
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Application of reflux classifier with closely spaced inclined channels in pre-concentrate process of fine antimony oxide particles 被引量:3
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作者 LIU Zhen-qiang LU Dong-fang +3 位作者 WANG Yu-hua CHU Hao-ran ZHENG Xia-yu CHEN Fu-lin 《Journal of Central South University》 SCIE EI CAS CSCD 2020年第11期3290-3301,共12页
In this work,the reflux classifier with closely spaced inclined channels is used as the pre-concentration facility to improve the separation efficiency before the shaking table separation.Three operating parameters of... In this work,the reflux classifier with closely spaced inclined channels is used as the pre-concentration facility to improve the separation efficiency before the shaking table separation.Three operating parameters of reflux classifier(RC)to pre-concentrate fine(0.023−0.15 mm)tailings of antimony oxide were optimized by response surface methodology(RSM)using a three-level Box-Behnken design(BBD).The parameters studied for the optimization were feeding speed,underflow,and ascending water speed.Second-order response functions were produced for the Sb grade and recovery rate of the concentrate.Taking advantage of the quadratic programming,when the factors of feeding,underflow and ascending water are respectively 225,30 and 133 cm^3/min,a better result can be achieved for the concentrate grade of 2.31% and recovery rate of 83.17%.At the same time,70.48% of the tailings with the grade of 0.20% were discarded out of the feeding.The results indicated that the reflux classifier has a good performance in dealing with fine tailings of antimony oxide.Moreover,second-order polynomial equations,ANOVA,and three-dimensional surface plots were developed to evaluate the effects of each parameter on Sb grade and recovery rate of the concentrate. 展开更多
关键词 reflux classifier antimony oxide PRE-CONCENTRATION inclined channels
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