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Detection of Turbulence Anomalies Using a Symbolic Classifier Algorithm in Airborne Quick Access Record(QAR)Data Analysis
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作者 Zibo ZHUANG Kunyun LIN +1 位作者 Hongying ZHANG Pak-Wai CHAN 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第7期1438-1449,共12页
As the risks associated with air turbulence are intensified by climate change and the growth of the aviation industry,it has become imperative to monitor and mitigate these threats to ensure civil aviation safety.The ... As the risks associated with air turbulence are intensified by climate change and the growth of the aviation industry,it has become imperative to monitor and mitigate these threats to ensure civil aviation safety.The eddy dissipation rate(EDR)has been established as the standard metric for quantifying turbulence in civil aviation.This study aims to explore a universally applicable symbolic classification approach based on genetic programming to detect turbulence anomalies using quick access recorder(QAR)data.The detection of atmospheric turbulence is approached as an anomaly detection problem.Comparative evaluations demonstrate that this approach performs on par with direct EDR calculation methods in identifying turbulence events.Moreover,comparisons with alternative machine learning techniques indicate that the proposed technique is the optimal methodology currently available.In summary,the use of symbolic classification via genetic programming enables accurate turbulence detection from QAR data,comparable to that with established EDR approaches and surpassing that achieved with machine learning algorithms.This finding highlights the potential of integrating symbolic classifiers into turbulence monitoring systems to enhance civil aviation safety amidst rising environmental and operational hazards. 展开更多
关键词 turbulence detection symbolic classifier quick access recorder data
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Using Cross Entropy as a Performance Metric for Quantifying Uncertainty in DNN Image Classifiers: An Application to Classification of Lung Cancer on CT Images
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作者 Eri Matsuyama Masayuki Nishiki +1 位作者 Noriyuki Takahashi Haruyuki Watanabe 《Journal of Biomedical Science and Engineering》 2024年第1期1-12,共12页
Cross entropy is a measure in machine learning and deep learning that assesses the difference between predicted and actual probability distributions. In this study, we propose cross entropy as a performance evaluation... Cross entropy is a measure in machine learning and deep learning that assesses the difference between predicted and actual probability distributions. In this study, we propose cross entropy as a performance evaluation metric for image classifier models and apply it to the CT image classification of lung cancer. A convolutional neural network is employed as the deep neural network (DNN) image classifier, with the residual network (ResNet) 50 chosen as the DNN archi-tecture. The image data used comprise a lung CT image set. Two classification models are built from datasets with varying amounts of data, and lung cancer is categorized into four classes using 10-fold cross-validation. Furthermore, we employ t-distributed stochastic neighbor embedding to visually explain the data distribution after classification. Experimental results demonstrate that cross en-tropy is a highly useful metric for evaluating the reliability of image classifier models. It is noted that for a more comprehensive evaluation of model perfor-mance, combining with other evaluation metrics is considered essential. . 展开更多
关键词 Cross Entropy Performance Metrics DNN Image classifiers Lung Cancer Prediction Uncertainty
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RefluxClassifier分离细颗粒的技术发展与应用前景
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作者 马梦绮 张志远 +2 位作者 荆隆隆 方佳豪 李延锋 《有色金属(选矿部分)》 CAS 2024年第1期106-115,共10页
矿石综采技术带来诸多便利的同时,也导致了矿石中细颗粒比例增多。细颗粒分离成为了国内外矿物加工领域面临的难题。由于细颗粒质量小、比表面积大、表面能高、容易团聚,进而难以有效分离。本世纪初,由澳大利亚学者Galvin所研制的Reflux... 矿石综采技术带来诸多便利的同时,也导致了矿石中细颗粒比例增多。细颗粒分离成为了国内外矿物加工领域面临的难题。由于细颗粒质量小、比表面积大、表面能高、容易团聚,进而难以有效分离。本世纪初,由澳大利亚学者Galvin所研制的RefluxClassifier(回流分级机,简称RC)作为一种新型重力分选设备进入到矿物加工设备行列。该设备由液固流化床与倾斜通道组成,分为垂直段与倾斜段,具有操作简单、成本低廉和高效节能等优点。据研究,RC因其特殊的结构与工作机理可以有效解决细颗粒分离问题。本文首先归纳了国内外有关RC的理论研究,详细描述了RC倾斜段中颗粒在流体中的运动状态,阐明了倾斜通道内颗粒运动与流体流动特性之间的关系,简要分析了颗粒性质与流体之间的力与速度关系。此外,本文对目前现有RC的水速预测模型(经典动力学模型、经验模型、弱化粒度模型、平衡模型)进行了总结,并综合分析了各模型的适用范围。结合试验案例,介绍了RC在煤炭、黑金属、砂石骨料等领域的应用现状,举例分析不同试验条件下RC对细颗粒回收的分离情况。最后结合我国资源现状与现代设备发展趋势,提出如何深入优化RC分选理论模型、拓展更广阔的应用领域是国内外学者的长期研究目标,并展望RC在工业范围内的全面推广。 展开更多
关键词 Refluxclassifier 细粒回收 重力分选 颗粒运动
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CL2ES-KDBC:A Novel Covariance Embedded Selection Based on Kernel Distributed Bayes Classifier for Detection of Cyber-Attacks in IoT Systems
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作者 Talal Albalawi P.Ganeshkumar 《Computers, Materials & Continua》 SCIE EI 2024年第3期3511-3528,共18页
The Internet of Things(IoT)is a growing technology that allows the sharing of data with other devices across wireless networks.Specifically,IoT systems are vulnerable to cyberattacks due to its opennes The proposed wo... The Internet of Things(IoT)is a growing technology that allows the sharing of data with other devices across wireless networks.Specifically,IoT systems are vulnerable to cyberattacks due to its opennes The proposed work intends to implement a new security framework for detecting the most specific and harmful intrusions in IoT networks.In this framework,a Covariance Linear Learning Embedding Selection(CL2ES)methodology is used at first to extract the features highly associated with the IoT intrusions.Then,the Kernel Distributed Bayes Classifier(KDBC)is created to forecast attacks based on the probability distribution value precisely.In addition,a unique Mongolian Gazellas Optimization(MGO)algorithm is used to optimize the weight value for the learning of the classifier.The effectiveness of the proposed CL2ES-KDBC framework has been assessed using several IoT cyber-attack datasets,The obtained results are then compared with current classification methods regarding accuracy(97%),precision(96.5%),and other factors.Computational analysis of the CL2ES-KDBC system on IoT intrusion datasets is performed,which provides valuable insight into its performance,efficiency,and suitability for securing IoT networks. 展开更多
关键词 IoT security attack detection covariance linear learning embedding selection kernel distributed bayes classifier mongolian gazellas optimization
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Mammogram Classification with HanmanNets Using Hanman Transform Classifier
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作者 Jyoti Dabass Madasu Hanmandlu +1 位作者 Rekha Vig Shantaram Vasikarla 《Journal of Modern Physics》 2024年第7期1045-1067,共23页
Breast cancer is a deadly disease and radiologists recommend mammography to detect it at the early stages. This paper presents two types of HanmanNets using the information set concept for the derivation of deep infor... Breast cancer is a deadly disease and radiologists recommend mammography to detect it at the early stages. This paper presents two types of HanmanNets using the information set concept for the derivation of deep information set features from ResNet by modifying its kernel functions to yield Type-1 HanmanNets and then AlexNet, GoogLeNet and VGG-16 by changing their feature maps to yield Type-2 HanmanNets. The two types of HanmanNets exploit the final feature maps of these architectures in the generation of deep information set features from mammograms for their classification using the Hanman Transform Classifier. In this work, the characteristics of the abnormality present in the mammograms are captured using the above network architectures that help derive the features of HanmanNets based on information set concept and their performance is compared via the classification accuracies. The highest accuracy of 100% is achieved for the multi-class classifications on the mini-MIAS database thus surpassing the results in the literature. Validation of the results is done by the expert radiologists to show their clinical relevance. 展开更多
关键词 MAMMOGRAMS ResNet 18 Hanman Transform classifier ABNORMALITY DIAGNOSIS VGG-16 AlexNet GoogleNet HanmanNets
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Fine-Tuning Cyber Security Defenses: Evaluating Supervised Machine Learning Classifiers for Windows Malware Detection
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作者 Islam Zada Mohammed Naif Alatawi +4 位作者 Syed Muhammad Saqlain Abdullah Alshahrani Adel Alshamran Kanwal Imran Hessa Alfraihi 《Computers, Materials & Continua》 SCIE EI 2024年第8期2917-2939,共23页
Malware attacks on Windows machines pose significant cybersecurity threats,necessitating effective detection and prevention mechanisms.Supervised machine learning classifiers have emerged as promising tools for malwar... Malware attacks on Windows machines pose significant cybersecurity threats,necessitating effective detection and prevention mechanisms.Supervised machine learning classifiers have emerged as promising tools for malware detection.However,there remains a need for comprehensive studies that compare the performance of different classifiers specifically for Windows malware detection.Addressing this gap can provide valuable insights for enhancing cybersecurity strategies.While numerous studies have explored malware detection using machine learning techniques,there is a lack of systematic comparison of supervised classifiers for Windows malware detection.Understanding the relative effectiveness of these classifiers can inform the selection of optimal detection methods and improve overall security measures.This study aims to bridge the research gap by conducting a comparative analysis of supervised machine learning classifiers for detecting malware on Windows systems.The objectives include Investigating the performance of various classifiers,such as Gaussian Naïve Bayes,K Nearest Neighbors(KNN),Stochastic Gradient Descent Classifier(SGDC),and Decision Tree,in detecting Windows malware.Evaluating the accuracy,efficiency,and suitability of each classifier for real-world malware detection scenarios.Identifying the strengths and limitations of different classifiers to provide insights for cybersecurity practitioners and researchers.Offering recommendations for selecting the most effective classifier for Windows malware detection based on empirical evidence.The study employs a structured methodology consisting of several phases:exploratory data analysis,data preprocessing,model training,and evaluation.Exploratory data analysis involves understanding the dataset’s characteristics and identifying preprocessing requirements.Data preprocessing includes cleaning,feature encoding,dimensionality reduction,and optimization to prepare the data for training.Model training utilizes various supervised classifiers,and their performance is evaluated using metrics such as accuracy,precision,recall,and F1 score.The study’s outcomes comprise a comparative analysis of supervised machine learning classifiers for Windows malware detection.Results reveal the effectiveness and efficiency of each classifier in detecting different types of malware.Additionally,insights into their strengths and limitations provide practical guidance for enhancing cybersecurity defenses.Overall,this research contributes to advancing malware detection techniques and bolstering the security posture of Windows systems against evolving cyber threats. 展开更多
关键词 Security and privacy challenges in the context of requirements engineering supervisedmachine learning malware detection windows systems comparative analysis Gaussian Naive Bayes K Nearest Neighbors Stochastic Gradient Descent classifier Decision Tree
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Model-Free Ultra-High-Dimensional Feature Screening for Multi-Classified Response Data Based on Weighted Jensen-Shannon Divergence
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作者 Qingqing Jiang Guangming Deng 《Open Journal of Statistics》 2023年第6期822-849,共28页
In ultra-high-dimensional data, it is common for the response variable to be multi-classified. Therefore, this paper proposes a model-free screening method for variables whose response variable is multi-classified fro... In ultra-high-dimensional data, it is common for the response variable to be multi-classified. Therefore, this paper proposes a model-free screening method for variables whose response variable is multi-classified from the point of view of introducing Jensen-Shannon divergence to measure the importance of covariates. The idea of the method is to calculate the Jensen-Shannon divergence between the conditional probability distribution of the covariates on a given response variable and the unconditional probability distribution of the covariates, and then use the probabilities of the response variables as weights to calculate the weighted Jensen-Shannon divergence, where a larger weighted Jensen-Shannon divergence means that the covariates are more important. Additionally, we also investigated an adapted version of the method, which is to measure the relationship between the covariates and the response variable using the weighted Jensen-Shannon divergence adjusted by the logarithmic factor of the number of categories when the number of categories in each covariate varies. Then, through both theoretical and simulation experiments, it was demonstrated that the proposed methods have sure screening and ranking consistency properties. Finally, the results from simulation and real-dataset experiments show that in feature screening, the proposed methods investigated are robust in performance and faster in computational speed compared with an existing method. 展开更多
关键词 Ultra-High-Dimensional Multi-classified Weighted Jensen-Shannon Divergence MODEL-FREE Feature Screening
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A novel molecular classification method for osteosarcoma based on tumor cell differentiation trajectories 被引量:1
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作者 Hao Zhang Ting Wang +16 位作者 Haiyi Gong Runyi Jiang Wang Zhou Haitao Sun Runzhi Huang Yao Wang Zhipeng Wu Wei Xu Zhenxi Li Quan Huang Xiaopan Cai Zaijun Lin Jinbo Hu Qi Jia Chen Ye Haifeng Wei Jianru Xiao 《Bone Research》 SCIE CAS CSCD 2023年第1期148-162,共15页
Subclassification of tumors based on molecular features may facilitate therapeutic choice and increase the response rate of cancer patients.However,the highly complex cell origin involved in osteosarcoma(OS)limits the... Subclassification of tumors based on molecular features may facilitate therapeutic choice and increase the response rate of cancer patients.However,the highly complex cell origin involved in osteosarcoma(OS)limits the utility of traditional bulk RNA sequencing for OS subclassification.Single-cell RNA sequencing(sc RNA-seq)holds great promise for identifying cell heterogeneity.However,this technique has rarely been used in the study of tumor subclassification.By analyzing sc RNA-seq data for six conventional OS and nine cancellous bone(CB)samples,we identified 29 clusters in OS and CB samples and discovered three differentiation trajectories from the cancer stem cell(CSC)-like subset,which allowed us to classify OS samples into three groups.The classification model was further examined using the TARGET dataset.Each subgroup of OS had different prognoses and possible drug sensitivities,and OS cells in the three differentiation branches showed distinct interactions with other clusters in the OS microenvironment.In addition,we verified the classification model through IHC staining in 138 OS samples,revealing a worse prognosis for Group B patients.Furthermore,we describe the novel transcriptional program of CSCs and highlight the activation of EZH2 in CSCs of OS.These findings provide a novel subclassification method based on sc RNA-seq and shed new light on the molecular features of CSCs in OS and may serve as valuable references for precision treatment for and therapeutic development in OS. 展开更多
关键词 OSTEOSARCOMA holds classify
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REMOTE SENSING IMAGE CODING METHOD COMBINING WAVELET TRANSFORM WITH CLASSIFIED VECTOR QUANTIZATION
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作者 张正阳 吴成柯 《Chinese Journal of Aeronautics》 SCIE EI CSCD 1998年第3期55-60,共6页
A new remote sensing image coding scheme based on the wavelet transform and classified vector quantization (CVQ) is proposed. The original image is first decomposed into a hierarchy of 3 layers including 10 subimages ... A new remote sensing image coding scheme based on the wavelet transform and classified vector quantization (CVQ) is proposed. The original image is first decomposed into a hierarchy of 3 layers including 10 subimages by DWT. The lowest frequency subimage is compressed by scalar quantization and ADPCM. The high frequency subimages are compressed by CVQ to utilize the similarity among different resolutions while improving the edge quality and reducing computational complexity. The experimental results show that the proposed scheme has a better performance than JPEG, and a PSNR of reconstructed image is 31~33 dB with a rate of 0.2 bpp. 展开更多
关键词 remote sensing image coding wavelet transform classified vector quantization
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Classified recognition for metal magnetic memory signals of welding defects in API 5L X65 pipeline steel
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作者 张建军 邸新杰 +2 位作者 金宝 郭晓疆 李午申 《China Welding》 EI CAS 2012年第3期27-32,共6页
Feature extraction and selection from signals is a key issue for metal magnetic memory testing technique. In order to realize the classification of metal magnetic memory signals of welding defects, four fractal analys... Feature extraction and selection from signals is a key issue for metal magnetic memory testing technique. In order to realize the classification of metal magnetic memory signals of welding defects, four fractal analysis methods, such as box- counting, detrended fluctuation, minimal cover and rescaled-range analysis, were used to extract the feature signal after the original metal magnet memory signal was de-noising and differential processing, then the Karhunen-Lo^e transformation was adopted as classification tool to identify the defect signals. The result shows that this study can provide an efficient classification method for metal magnetic memory signal of welding defects. 展开更多
关键词 welding defect metal magnetic memory fractal analysis classified recognition
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Investigation of Inhabitants' Wishes on Classified Collection of Waste in Wanghua District of Fushun
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作者 Yanfeng Zhao Yafan Wang 《Meteorological and Environmental Research》 CAS 2013年第9期19-21,共3页
In order to disclose present situation and problem of classified collection of municipal solid waste in Wanghua District of Fushun and ana- lyze its practicability, questionnaire was designed in this paper, random res... In order to disclose present situation and problem of classified collection of municipal solid waste in Wanghua District of Fushun and ana- lyze its practicability, questionnaire was designed in this paper, random research was adopted in Wanghua District, and statistic analysis of investi- gation result was conducted. This investigation could provide basis for popularizing classified collection of municipal solid waste in the whole nation. 展开更多
关键词 Municipal solid waste classified collection Questionnaire investigation Residents' wishes China
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An Improved LSTM-PCA Ensemble Classifier for SQL Injection and XSS Attack Detection 被引量:1
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作者 Deris Stiawan Ali Bardadi +7 位作者 Nurul Afifah Lisa Melinda Ahmad Heryanto Tri Wanda Septian Mohd Yazid Idris Imam Much Ibnu Subroto Lukman Rahmat Budiarto 《Computer Systems Science & Engineering》 SCIE EI 2023年第8期1759-1774,共16页
The Repository Mahasiswa(RAMA)is a national repository of research reports in the form of final assignments,student projects,theses,dissertations,and research reports of lecturers or researchers that have not yet been... The Repository Mahasiswa(RAMA)is a national repository of research reports in the form of final assignments,student projects,theses,dissertations,and research reports of lecturers or researchers that have not yet been published in journals,conferences,or integrated books from the scientific repository of universities and research institutes in Indonesia.The increasing popularity of the RAMA Repository leads to security issues,including the two most widespread,vulnerable attacks i.e.,Structured Query Language(SQL)injection and cross-site scripting(XSS)attacks.An attacker gaining access to data and performing unauthorized data modifications is extremely dangerous.This paper aims to provide an attack detection system for securing the repository portal from the abovementioned attacks.The proposed system combines a Long Short–Term Memory and Principal Component Analysis(LSTM-PCA)model as a classifier.This model can effectively solve the vanishing gradient problem caused by excessive positive samples.The experiment results show that the proposed system achieves an accuracy of 96.85%using an 80%:20%ratio of training data and testing data.The rationale for this best achievement is that the LSTM’s Forget Gate works very well as the PCA supplies only selected features that are significantly relevant to the attacks’patterns.The Forget Gate in LSTM is responsible for deciding which information should be kept for computing the cell state and which one is not relevant and can be discarded.In addition,the LSTM’s Input Gate assists in finding out crucial information and stores specific relevant data in the memory. 展开更多
关键词 LSTM PCA ensemble classifier SQL injection XSS
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BS-SC Model:A Novel Method for Predicting Child Abuse Using Borderline-SMOTE Enabled Stacking Classifier 被引量:1
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作者 Saravanan Parthasarathy Arun Raj Lakshminarayanan 《Computer Systems Science & Engineering》 SCIE EI 2023年第8期1311-1336,共26页
For a long time,legal entities have developed and used crime prediction methodologies.The techniques are frequently updated based on crime evaluations and responses from scientific communities.There is a need to devel... For a long time,legal entities have developed and used crime prediction methodologies.The techniques are frequently updated based on crime evaluations and responses from scientific communities.There is a need to develop type-based crime prediction methodologies that can be used to address issues at the subgroup level.Child maltreatment is not adequately addressed because children are voiceless.As a result,the possibility of developing a model for predicting child abuse was investigated in this study.Various exploratory analysis methods were used to examine the city of Chicago’s child abuse events.The data set was balanced using the Borderline-SMOTE technique,and then a stacking classifier was employed to ensemble multiple algorithms to predict various types of child abuse.The proposed approach successfully predicted crime types with 93%of accuracy,precision,recall,and F1-Score.The AUC value of the same was 0.989.However,when compared to the Extra Trees model(17.55),which is the second best,the proposed model’s execution time was significantly longer(476.63).We discovered that Machine Learning methods effectively evaluate the demographic and spatial-temporal characteristics of the crimes and predict the occurrences of various subtypes of child abuse.The results indicated that the proposed Borderline-SMOTE enabled Stacking Classifier model(BS-SC Model)would be effective in the real-time child abuse prediction and prevention process. 展开更多
关键词 Child abuse sexual offending DECISION-MAKING machine learning stacking classifier
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Changes in classified precipitation in the urban, suburban, and mountain areas of Beijing
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作者 YUAN Yu-Feng ZHAI Pan-Mao +1 位作者 LI Jian CHEN Yang 《Advances in Climate Change Research》 SCIE CSCD 2017年第4期279-285,共7页
In this paper, based on hourly precipitation observations in 1977e2013 in the Beijing area, China, hourly precipitation in summer (June?August) is classified into three categories: light (below the 50th percentile val... In this paper, based on hourly precipitation observations in 1977e2013 in the Beijing area, China, hourly precipitation in summer (June?August) is classified into three categories: light (below the 50th percentile values), moderate (the 50th to 95th percentile values), and heavy (above the 95th percentile values). Results reveal that both light and moderate precipitation decreased significantly during the research period and thereby caused the decrease in summer totals. By contrast, pronounced trends failed to be detected in the heavy category. Since 2004, the contribution of heavy rainfall to the summer total precipitation in the urban area increased as compared to the suburban area, which is opposite to light rainfall. There are obvious differences in the diurnal variations of classified precipitation. Light precipitation shows a double peak structure in the early morning and at night, while moderate and heavy rainfall show a single peak at night. Light precipitation at the early morning peak time decreased significantly in the whole Beijing area. Compared with the suburban area, light precipitation in the urban area occurred less frequently whereas heavy precipitation occurred more frequently at evening peak time after 2004. The asymmetry of the rainfall is obvious, especially, for heavy precipitation. The asymmetry of heavy precipitation events in the urban area exhibits a significant increasing trend. 展开更多
关键词 Hourly PRECIPITATION classified PRECIPITATION DIURNAL variation Asymmetry BEIJING
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Observation points classifier ensemble for high-dimensional imbalanced classification 被引量:1
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作者 Yulin He Xu Li +3 位作者 Philippe Fournier‐Viger Joshua Zhexue Huang Mianjie Li Salman Salloum 《CAAI Transactions on Intelligence Technology》 SCIE EI 2023年第2期500-517,共18页
In this paper,an Observation Points Classifier Ensemble(OPCE)algorithm is proposed to deal with High-Dimensional Imbalanced Classification(HDIC)problems based on data processed using the Multi-Dimensional Scaling(MDS)... In this paper,an Observation Points Classifier Ensemble(OPCE)algorithm is proposed to deal with High-Dimensional Imbalanced Classification(HDIC)problems based on data processed using the Multi-Dimensional Scaling(MDS)feature extraction technique.First,dimensionality of the original imbalanced data is reduced using MDS so that distances between any two different samples are preserved as well as possible.Second,a novel OPCE algorithm is applied to classify imbalanced samples by placing optimised observation points in a low-dimensional data space.Third,optimization of the observation point mappings is carried out to obtain a reliable assessment of the unknown samples.Exhaustive experiments have been conducted to evaluate the feasibility,rationality,and effectiveness of the proposed OPCE algorithm using seven benchmark HDIC data sets.Experimental results show that(1)the OPCE algorithm can be trained faster on low-dimensional imbalanced data than on high-dimensional data;(2)the OPCE algorithm can correctly identify samples as the number of optimised observation points is increased;and(3)statistical analysis reveals that OPCE yields better HDIC performances on the selected data sets in comparison with eight other HDIC algorithms.This demonstrates that OPCE is a viable algorithm to deal with HDIC problems. 展开更多
关键词 classifier ensemble feature transformation high-dimensional data classification imbalanced learning observation point mechanism
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Phytodiversity and Vulnerability of Protected Areas in Burkina Faso: Case of Péni Classified Forest
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作者 Nebnoma Romaric Tiendrébeogo Paulin Ouoba +5 位作者 Brigitte Bastide Yempabou Hermann Ouoba Blandine Marie Ivette Nacoulma Irénée Somda Bismarck Hassan Nacro Issiaka Joseph Boussim 《Journal of Geoscience and Environment Protection》 2022年第12期204-223,共20页
Protected areas contain most of Burkina Faso’s plant biodiversity which confer different benefits for the communities. However, the composition of some of them remains unknown. In a context of overexploitation and cl... Protected areas contain most of Burkina Faso’s plant biodiversity which confer different benefits for the communities. However, the composition of some of them remains unknown. In a context of overexploitation and climate change, it is important to have a detailed knowledge of the vegetation of forests that have not been studied, such as Péni Classified Forest (PCF) to develop better preservation protocols. The aim of this study is to contribute to the knowledge of the flora of Burkina Faso. Phytosociological surveys were carried out in 213 plots, have identified 475 species distributed in 321 genera and 87 families. We identified during this study 201 woody species representing 38% of the woody flora of Burkina Faso. 64% of this flora is confined to shrub savannahs and 61% to tree savannahs. Among the vegetation units, shrub savannahs and tree savannahs have respectively 56.21% and 44.67% of very rare species. Poaceae (11.90%), Fabaceae-Faboideae (11.27%) and Rubiaceae (6.26%) are the most dominant families. The dominant biological types of the flora are phanerophytes (42.32%) and therophytes (30.32%), and Sudanian species (20.63%) are the best represented. Logging is the most frequent disturbance factor (100%) in the PCF. The PCF is a particular ecosystem with a great diversity but subject to many disturbances. Actions to strengthen its protection are necessary. 展开更多
关键词 BIODIVERSITY ECOLOGY Anthropic Pressures classified Forests Burkina Faso
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On the Application of Classified English Teaching in Vocational School
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作者 王燕侬 《海外英语》 2012年第8X期93-95,共3页
Over the past years,with the increasing enrollment of high school,vocational schools are facing great challenge for their existence and development,concerning the low proficiency of the students and great gap among th... Over the past years,with the increasing enrollment of high school,vocational schools are facing great challenge for their existence and development,concerning the low proficiency of the students and great gap among them.The traditional English teaching mode which employs the same teaching contents,same teaching methods and teaching aims cannot satisfy students with different English levels.Therefore,in order to change the present situation,this paper proposes a new English teaching mode:classified English teaching.In the new mode,different students will be taught by different materials,different methods and with different aims.It can stimulate students'enthusiasm in English learning,and make every student develop appropriately. 展开更多
关键词 classified ENGLISH TEACHING VOCATIONAL SCHOOL appl
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Construction of the Forecast System of Classified Severe Convection Weather in Qinghai Province Based on Ingredients-based Method
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作者 Qin GUAN Xinfu YAO +3 位作者 Qingping LI Jinhai LI Yao HU Bianbian ZHANG 《Meteorological and Environmental Research》 CAS 2022年第5期47-55,共9页
Based on the data of the cases of severe convection weather such as hail,thunderstorm(thunderstorm gale)and short-time heavy precipitation in recent 10 years,the spatial and temporal distribution characteristics of di... Based on the data of the cases of severe convection weather such as hail,thunderstorm(thunderstorm gale)and short-time heavy precipitation in recent 10 years,the spatial and temporal distribution characteristics of different types of severe convection weather were analyzed.The results show that the frequency of severe convection weather tended to increase,of which short-time heavy precipitation and thunderstorm weather rose,and hail and thunderstorm gale weather decreased.Severe convection weather began to extend in late spring and early autumn.Typical cases were selected to analyze the evolution mechanism,and the conceptual models of severe convective weather caused by cold advection forcing,warm advection forcing and baroclinic frontogenesis were obtained.The key predictors for the potential prediction of severe convection weather were proposed,such as CAPE(convective available potential energy)for hail weather,UH index(maximum ascending helicity)for thunderstorm gale and PWV(precipitable water vapor)for short-time heavy precipitation.ERA5 data were used to get the forecast threshold of the key factor of classified severe convection weather,and it was verified that the threshold was available.Meanwhile,the causes of the error of failure cases were analyzed.For instance,the larger deviation of CAPE was caused by the 2 m deviation of temperature.Supplementary correction method and threshold were given to provide a reference for the objective forecast and early warning of severe convection weather. 展开更多
关键词 classified strong convection Convective available potential energy Rising helicity Atmospheric precipitable water Threshold
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Ensemble Classifier Design Based on Perturbation Binary Salp Swarm Algorithm for Classification
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作者 Xuhui Zhu Pingfan Xia +2 位作者 Qizhi He Zhiwei Ni Liping Ni 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第4期653-671,共19页
Multiple classifier system exhibits strong classification capacity compared with single classifiers,but they require significant computational resources.Selective ensemble system aims to attain equivalent or better cl... Multiple classifier system exhibits strong classification capacity compared with single classifiers,but they require significant computational resources.Selective ensemble system aims to attain equivalent or better classification accuracy with fewer classifiers.However,current methods fail to identify precise solutions for constructing an ensemble classifier.In this study,we propose an ensemble classifier design technique based on the perturbation binary salp swarm algorithm(ECDPB).Considering that extreme learning machines(ELMs)have rapid learning rates and good generalization ability,they can serve as the basic classifier for creating multiple candidates while using fewer computational resources.Meanwhile,we introduce a combined diversity measure by taking the complementarity and accuracy of ELMs into account;it is used to identify the ELMs that have good diversity and low error.In addition,we propose an ECDPB with powerful optimizing ability;it is employed to find the optimal subset of ELMs.The selected ELMs can then be used to forman ensemble classifier.Experiments on 10 benchmark datasets have been conducted,and the results demonstrate that the proposed ECDPB delivers superior classification capacity when compared with alternative methods. 展开更多
关键词 Ensemble classifier salp swarmalgorithm diversity measure multiple classifiers system extreme learning machine
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Age and Gender Classification Using Backpropagation and Bagging Algorithms
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作者 Ammar Almomani Mohammed Alweshah +6 位作者 Waleed Alomoush Mohammad Alauthman Aseel Jabai Anwar Abbass Ghufran Hamad Meral Abdalla Brij B.Gupta 《Computers, Materials & Continua》 SCIE EI 2023年第2期3045-3062,共18页
Voice classification is important in creating more intelligent systems that help with student exams,identifying criminals,and security systems.The main aim of the research is to develop a system able to predicate and ... Voice classification is important in creating more intelligent systems that help with student exams,identifying criminals,and security systems.The main aim of the research is to develop a system able to predicate and classify gender,age,and accent.So,a newsystem calledClassifyingVoice Gender,Age,and Accent(CVGAA)is proposed.Backpropagation and bagging algorithms are designed to improve voice recognition systems that incorporate sensory voice features such as rhythm-based features used to train the device to distinguish between the two gender categories.It has high precision compared to other algorithms used in this problem,as the adaptive backpropagation algorithm had an accuracy of 98%and the Bagging algorithm had an accuracy of 98.10%in the gender identification data.Bagging has the best accuracy among all algorithms,with 55.39%accuracy in the voice common dataset and age classification and accent accuracy in a speech accent of 78.94%. 展开更多
关键词 Classify voice gender ACCENT age bagging algorithms back propagation algorithms AI classifiers
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