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Adaptive target and jamming recognition for the pulse doppler radar fuze based on a time-frequency joint feature and an online-updated naive bayesian classifier with minimal risk 被引量:7
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作者 Jian Dai Xin-hong Hao +2 位作者 Ze Li Ping Li Xiao-peng Yan 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2022年第3期457-466,共10页
This paper considers the problem of target and jamming recognition for the pulse Doppler radar fuze(PDRF).To solve the problem,the matched filter outputs of the PDRF under the action of target and jamming are analyzed... This paper considers the problem of target and jamming recognition for the pulse Doppler radar fuze(PDRF).To solve the problem,the matched filter outputs of the PDRF under the action of target and jamming are analyzed.Then,the frequency entropy and peak-to-peak ratio are extracted from the matched filter output of the PDRF,and the time-frequency joint feature is constructed.Based on the time-frequency joint feature,the naive Bayesian classifier(NBC)with minimal risk is established for target and jamming recognition.To improve the adaptability of the proposed method in complex environments,an online update process that adaptively modifies the classifier in the duration of the work of the PDRF is proposed.The experiments show that the PDRF can maintain high recognition accuracy when the signal-to-noise ratio(SNR)decreases and the jamming-to-signal ratio(JSR)increases.Moreover,the applicable analysis shows that he ONBCMR method has low computational complexity and can fully meet the real-time requirements of PDRF. 展开更多
关键词 Pulse Doppler radar fuze(PDRF) Target and jamming recognition Time-frequency joint feature Online-update naive Bayesian classifier minimal risk(ONBCMR)
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Video Concept Detection Based on Multiple Features and Classifiers Fusion 被引量:1
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作者 Dong Yuan Zhang Jiwei +2 位作者 Zhao Nan Chang Xiaofu Liu Wei 《China Communications》 SCIE CSCD 2012年第8期105-121,共17页
The rapid growth of multimedia content necessitates powerful technologies to filter, classify, index and retrieve video documents more efficiently. However, the essential bottleneck of image and video analysis is the ... The rapid growth of multimedia content necessitates powerful technologies to filter, classify, index and retrieve video documents more efficiently. However, the essential bottleneck of image and video analysis is the problem of semantic gap that low level features extracted by computers always fail to coincide with high-level concepts interpreted by humans. In this paper, we present a generic scheme for the detection video semantic concepts based on multiple visual features machine learning. Various global and local low-level visual features are systelrtically investigated, and kernelbased learning method equips the concept detection system to explore the potential of these features. Then we combine the different features and sub-systen on both classifier-level and kernel-level fusion that contribute to a more robust system Our proposed system is tested on the TRECVID dataset. The resulted Mean Average Precision (MAP) score is rmch better than the benchmark perforrmnce, which proves that our concepts detection engine develops a generic model and perforrrs well on both object and scene type concepts. 展开更多
关键词 concept detection visual feature extraction kemel-based learning classifier fusion
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Decision Bayes Criteria for Optimal Classifier Based on Probabilistic Measures 被引量:1
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作者 Wissal Drira Faouzi Ghorbel 《Journal of Electronic Science and Technology》 CAS 2014年第2期216-219,共4页
This paper addresses the high dimension sample problem in discriminate analysis under nonparametric and supervised assumptions. Since there is a kind of equivalence between the probabilistic dependence measure and the... This paper addresses the high dimension sample problem in discriminate analysis under nonparametric and supervised assumptions. Since there is a kind of equivalence between the probabilistic dependence measure and the Bayes classification error probability, we propose to use an iterative algorithm to optimize the dimension reduction for classification with a probabilistic approach to achieve the Bayes classifier. The estimated probabilities of different errors encountered along the different phases of the system are realized by the Kernel estimate which is adjusted in a means of the smoothing parameter. Experiment results suggest that the proposed approach performs well. 展开更多
关键词 Bayesian classifier dimension reduction kernel method optimization probabilistic dependence measure smoothing parameter
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Modeling the effects of mechanical parameters on the hydrodynamic behavior of vertical current classifiers 被引量:3
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作者 Arabzadeh Jarkani Soroush Khoshdast Hamid +1 位作者 Shariat Elaheh Sam Abbas 《International Journal of Mining Science and Technology》 SCIE EI 2014年第1期123-127,共5页
This study modeled the effects of structural and dimensional manipulations on hydrodynamic behavior of a bench vertical current classifier. Computational fluid dynamics (CFD) approach was used as modeling method, an... This study modeled the effects of structural and dimensional manipulations on hydrodynamic behavior of a bench vertical current classifier. Computational fluid dynamics (CFD) approach was used as modeling method, and turbulent intensity and fluid velocity were applied as system responses to predict the over- flow cut size variations. These investigations showed that cut size would decrease by increasing diameter and height of the separation column and cone section depth, due to the decrease of turbulent intensity and fluid velocity. As the size of discharge gate increases, the overflow cut-size would decrease due to freely fluid stream out of the column. The overflow cut-size was significantly increased in downward fed classifier compared to that fed by upward fluid stream. In addition, reforming the shape of angular overflow outlet's weir into the curved form prevented stream inside returning and consequently unselec- tire cut-size decreasing. 展开更多
关键词 Hydraulic classifier Modeling Computational fluid dynamic Cut size
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Common Spatial Pattern Ensemble Classifier and Its Application in Brain-Computer Interface 被引量:5
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作者 Xu Lei Ping Yang Peng Xu Tie-Jun Liu De-Zhong Yao 《Journal of Electronic Science and Technology of China》 2009年第1期17-21,共5页
Abstract-Common spatial pattern (CSP) algorithm is a successful tool in feature estimate of brain-computer interface (BCI). However, CSP is sensitive to outlier and may result in poor outcomes since it is based on... Abstract-Common spatial pattern (CSP) algorithm is a successful tool in feature estimate of brain-computer interface (BCI). However, CSP is sensitive to outlier and may result in poor outcomes since it is based on pooling the covariance matrices of trials. In this paper, we propose a simple yet effective approach, named common spatial pattern ensemble (CSPE) classifier, to improve CSP performance. Through division of recording channels, multiple CSP filters are constructed. By projection, log-operation, and subtraction on the original signal, an ensemble classifier, majority voting, is achieved and outlier contaminations are alleviated. Experiment results demonstrate that the proposed CSPE classifier is robust to various artifacts and can achieve an average accuracy of 83.02%. 展开更多
关键词 Brain-computer interface channel selection classifier ensemble common spatial pattern.
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An Algorithm for Idle-State Detection and Continuous Classifier Design in Motor-Imagery-Based BCI 被引量:3
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作者 Yu Huang Qiang Wu Xu Lei Ping Yang Peng Xu De-Zhong Yao 《Journal of Electronic Science and Technology of China》 2009年第1期27-33,共7页
Abstract-The development of asynchronous brain-computer interface (BCI) based on motor imagery (M1) poses the research in algorithms for detecting the nontask states (i.e., idle state) and the design of continuo... Abstract-The development of asynchronous brain-computer interface (BCI) based on motor imagery (M1) poses the research in algorithms for detecting the nontask states (i.e., idle state) and the design of continuous classifiers that classify continuously incoming electroencephalogram (EEG) samples. An algorithm is proposed in this paper which integrates two two-class classifiers to detect idle state and utilizes a sliding window to achieve continuous outputs. The common spatial pattern (CSP) algorithm is used to extract features of EEG signals and the linear support vector machine (SVM) is utilized to serve as classifier. The algorithm is applied on dataset IVb of BCI competition Ⅲ, with a resulting mean square error of 0.66. The result indicates that the proposed algorithm is feasible in the first step of the development of asynchronous systems. 展开更多
关键词 Brain-computer interface competition common spatial pattern continuous classifier idle state motor imagery support vector machine.
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Face Recognition Combining Eigen Features with a Parzen Classifier 被引量:1
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作者 孙鑫 刘兵 刘本永 《Journal of Electronic Science and Technology of China》 2005年第1期18-21,共4页
A face recognition scheme is proposed, wherein a face image is preprocessed by pixel averaging and energy normalizing to reduce data dimension and brightness variation effect, followed by the Fourier transform to esti... A face recognition scheme is proposed, wherein a face image is preprocessed by pixel averaging and energy normalizing to reduce data dimension and brightness variation effect, followed by the Fourier transform to estimate the spectrum of the preprocessed image. The principal component analysis is conducted on the spectra of a face image to obtain eigen features. Combining eigen features with a Parzen classifier, experiments are taken on the ORL face database. 展开更多
关键词 face recognition Fourier transform principal component analysis Parzen classifier pixel averaging energy normalizing
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Single-qubit quantum classifier based on gradient-free optimization algorithm
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作者 张安琪 王可伦 +1 位作者 吴逸华 赵生妹 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第10期241-247,共7页
A single-qubit quantum classifier(SQC)based on a gradient-free optimization(GFO)algorithm,named the GFO-based SQC,is proposed to overcome the effects of barren plateaus caused by quantum devices.Here,a rotation gate R... A single-qubit quantum classifier(SQC)based on a gradient-free optimization(GFO)algorithm,named the GFO-based SQC,is proposed to overcome the effects of barren plateaus caused by quantum devices.Here,a rotation gate R_(X)(φ)is applied on the single-qubit binary quantum classifier,and the training data and parameters are loaded intoφin the form of vector multiplication.The cost function is decreased by finding the value of each parameter that yields the minimum expectation value of measuring the quantum circuit.The algorithm is performed iteratively for all parameters one by one until the cost function satisfies the stop condition.The proposed GFO-based SQC is demonstrated for classification tasks in Iris and MNIST datasets and compared with the Adam-based SQC and the quantum support vector machine(QSVM).Furthermore,the performance of the GFO-based SQC is discussed when the rotation gate in the quantum device is under different types of noise.The simulation results show that the GFO-based SQC can reach a high accuracy in reduced time.Additionally,the proposed GFO algorithm can quickly complete the training process of the SQC.Importantly,the GFO-based SQC has a good performance in noisy environments. 展开更多
关键词 single-qubit quantum classifier gradient-free parameters optimizing barren plateau quantum noise
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Key-Attributes-Based Ensemble Classifier for Customer Churn Prediction
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作者 Yu Qian Liang-Qiang Li +1 位作者 Jian-Rong Ran Pei-Ji Shao 《Journal of Electronic Science and Technology》 CAS CSCD 2018年第1期37-44,共8页
Recently, it has been seen that the ensemble classifier is an effective way to enhance the prediction performance. However, it usually suffers from the problem of how to construct an appropriate classifier based on a ... Recently, it has been seen that the ensemble classifier is an effective way to enhance the prediction performance. However, it usually suffers from the problem of how to construct an appropriate classifier based on a set of complex data, for example,the data with many dimensions or hierarchical attributes. This study proposes a method to constructe an ensemble classifier based on the key attributes. In addition to its high-performance on precision shared by common ensemble classifiers, the calculation results are highly intelligible and thus easy for understanding.Furthermore, the experimental results based on the real data collected from China Mobile show that the keyattributes-based ensemble classifier has the good performance on both of the classifier construction and the customer churn prediction. 展开更多
关键词 Customer churn data mining ensemble classifier key attribute
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Evolutionary Algorithm with Ensemble Classifier Surrogate Model for Expensive Multiobjective Optimization
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作者 LAN Tian 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2020年第S01期76-87,共12页
For many real-world multiobjective optimization problems,the evaluations of the objective functions are computationally expensive.Such problems are usually called expensive multiobjective optimization problems(EMOPs).... For many real-world multiobjective optimization problems,the evaluations of the objective functions are computationally expensive.Such problems are usually called expensive multiobjective optimization problems(EMOPs).One type of feasible approaches for EMOPs is to introduce the computationally efficient surrogates for reducing the number of function evaluations.Inspired from ensemble learning,this paper proposes a multiobjective evolutionary algorithm with an ensemble classifier(MOEA-EC)for EMOPs.More specifically,multiple decision tree models are used as an ensemble classifier for the pre-selection,which is be more helpful for further reducing the function evaluations of the solutions than using single inaccurate model.The extensive experimental studies have been conducted to verify the efficiency of MOEA-EC by comparing it with several advanced multiobjective expensive optimization algorithms.The experimental results show that MOEA-EC outperforms the compared algorithms. 展开更多
关键词 multiobjective evolutionary algorithm expensive multiobjective optimization ensemble classifier surrogate model
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Operating Rule Classification System of Water Supply Reservoir Based on Learning Classifier System
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作者 张先锋 王小林 +1 位作者 尹正杰 李惠强 《Journal of Southwest Jiaotong University(English Edition)》 2008年第3期275-284,共10页
An operating rule classification system based on learning classifier system (LCS), which learns through credit assignment (bucket brigade algorithm, BBA) and rule discovery (genetic algorithm, GA), is establishe... An operating rule classification system based on learning classifier system (LCS), which learns through credit assignment (bucket brigade algorithm, BBA) and rule discovery (genetic algorithm, GA), is established to extract water-supply reservoir operating rules. The proposed system acquires an online identification rate of 95% for training samples and an offline rate of 85% for testing samples in a case study. The performances of the rule classification system are discussed from the rationality of the obtained rules, the impact of training samples on rule extraction, and a comparison between the rule classification system and the artificial neural network (ANN). The results indicate that the LCS is feasible and effective for the system to obtain the reservoir supply operating rules. 展开更多
关键词 Operating rules Water supply Learning classifier system Genetic algorithm
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Recognition of Characters by Adaptive Combination of Classifiers
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作者 王飞 李在铭 《Journal of Electronic Science and Technology of China》 2004年第2期7-9,共3页
In this paper, the visual feature space based on the long Horizontals, the long Verticals, and the radicals are given. An adaptive combination of classifiers, whose coefficients vary with the input pattern, is also pr... In this paper, the visual feature space based on the long Horizontals, the long Verticals, and the radicals are given. An adaptive combination of classifiers, whose coefficients vary with the input pattern, is also proposed. Experiments show that the approach is promising for character recognition in video sequences. 展开更多
关键词 character recognition adaptive combination multiple classifiers
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Intrusion Detection System Using Classification Algorithms with Feature Selection Mechanism over Real-Time Data Traffic 被引量:1
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作者 Gulab Sah Sweety Singh Subhasish Banerjee 《China Communications》 SCIE CSCD 2024年第9期292-320,共29页
The key objective of intrusion detection systems(IDS)is to protect the particular host or network by investigating and predicting the network traffic as an attack or normal.These IDS uses many methods of machine learn... The key objective of intrusion detection systems(IDS)is to protect the particular host or network by investigating and predicting the network traffic as an attack or normal.These IDS uses many methods of machine learning(ML)to learn from pastexperience attack i.e.signatures based and identify the new ones.Even though these methods are effective,but they have to suffer from large computational costs due to considering all the traffic features,together.Moreover,emerging technologies like the Internet of Things(Io T),big data,etc.are getting advanced day by day;as a result,network traffics are also increasing rapidly.Therefore,the issue of computational cost needs to be addressed properly.Thus,in this research,firstly,the ML methods have been used with the feature selection technique(FST)to reduce the number of features by picking out only the important ones from NSL-KDD,CICIDS2017,and CIC-DDo S2019datasets later that helped to build IDSs with lower cost but with the higher performance which would be appropriate for vast scale network.The experimental result demonstrated that the proposed model i.e.Decision tree(DT)with Recursive feature elimination(RFE)performs better than other classifiers with RFE in terms of accuracy,specificity,precision,sensitivity,F1-score,and G-means on the investigated datasets. 展开更多
关键词 CICIDS2017 dataset classifierS IDS ML NSL KDD dataset RFE
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LOCAL BAGGING AND ITS APPLICATIONON FACE RECOGNITION 被引量:1
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作者 朱玉莲 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2010年第3期255-260,共6页
Bagging is not quite suitable for stable classifiers such as nearest neighbor classifiers due to the lack of diversity and it is difficult to be directly applied to face recognition as well due to the small sample si... Bagging is not quite suitable for stable classifiers such as nearest neighbor classifiers due to the lack of diversity and it is difficult to be directly applied to face recognition as well due to the small sample size (SSS) property of face recognition. To solve the two problems,local Bagging (L-Bagging) is proposed to simultaneously make Bagging apply to both nearest neighbor classifiers and face recognition. The major difference between L-Bagging and Bagging is that L-Bagging performs the bootstrap sampling on each local region partitioned from the original face image rather than the whole face image. Since the dimensionality of local region is usually far less than the number of samples and the component classifiers are constructed just in different local regions,L-Bagging deals with SSS problem and generates more diverse component classifiers. Experimental results on four standard face image databases (AR,Yale,ORL and Yale B) indicate that the proposed L-Bagging method is effective and robust to illumination,occlusion and slight pose variation. 展开更多
关键词 face recognition local Bagging (L-Bagging) small sample size (SSS) nearest neighbor classifiers
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Application of Artificial Neural Network to Battlefield Target Classification
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作者 李芳 张中民 李科杰 《Journal of Beijing Institute of Technology》 EI CAS 2000年第2期201-204,共4页
To study the capacity of artificial neural network (ANN) applying to battlefield target classification and result of classification, according to the characteristics of battlefield target acoustic and seismic sign... To study the capacity of artificial neural network (ANN) applying to battlefield target classification and result of classification, according to the characteristics of battlefield target acoustic and seismic signals, an on the spot experiment was carried out to derive acoustic and seismic signals of a tank and jeep by special experiment system. Experiment data processed by fast Fourier transform(FFT) were used to train the ANN to distinguish the two battlefield targets. The ANN classifier was performed by the special program based on the modified back propagation (BP) algorithm. The ANN classifier has high correct identification rates for acoustic and seismic signals of battlefield targets, and is suitable for the classification of battlefield targets. The modified BP algorithm eliminates oscillations and local minimum of the standard BP algorithm, and enhances the convergence rate of the ANN. 展开更多
关键词 artificial neural network sample data classifier TRAINING
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基于生成对抗网络的无载体信息隐藏 被引量:31
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作者 刘明明 张敏情 +2 位作者 刘佳 高培贤 张英男 《应用科学学报》 CAS CSCD 北大核心 2018年第2期371-382,共12页
传统信息隐藏算法通过修改载体来嵌入秘密信息,难以从根本上抵抗基于统计的信息隐藏分析方法的检测,为此提出一种基于生成对抗网络的无载体信息隐藏方法.该方法将生成对抗网络中的类别标签替换为秘密信息作为驱动,直接生成含密图像进行... 传统信息隐藏算法通过修改载体来嵌入秘密信息,难以从根本上抵抗基于统计的信息隐藏分析方法的检测,为此提出一种基于生成对抗网络的无载体信息隐藏方法.该方法将生成对抗网络中的类别标签替换为秘密信息作为驱动,直接生成含密图像进行传递,再通过判别器将含密图像中的秘密信息提取出来,并借助生成对抗网络实现无载体信息隐藏.实验结果和分析表明,该隐藏方法在隐写容量、抗隐写分析、安全性方面均有良好表现. 展开更多
关键词 信息隐藏 无载体信息隐藏 生成对抗网络 ACGAN(auxiliary classifier GAN)
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Experimental validation of material discrimination ability of muon scattering tomography at the TUMUTY facility 被引量:10
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作者 Xing-Yu Pan Yi-Fan Zheng +2 位作者 Zhi Zeng Xue-Wu Wang Jian-Ping Cheng 《Nuclear Science and Techniques》 SCIE CAS CSCD 2019年第8期26-34,共9页
Muon scattering tomography is believed to be a promising technique for cargo container inspection, owing to the ability of natural muons to penetrate into dense materials and the absence of artificial radiation. In th... Muon scattering tomography is believed to be a promising technique for cargo container inspection, owing to the ability of natural muons to penetrate into dense materials and the absence of artificial radiation. In this work, the material discrimination ability of muon scattering tomography is evaluated based on experiments at the Tsinghua University cosmic ray muon tomography facility,with four materials: flour(as drugs substitute), aluminum,steel, and lead. The features of the different materials could be discriminated with cluster analysis and classifiers based on support vector machine. The overall discrimination precisions for these four materials could reach 70, 95, and 99% with 1-, 5-, and 10-min-long measurement,respectively. 展开更多
关键词 MUON TOMOGRAPHY CARGO containerinspection MATERIAL DISCRIMINATION SVM classifier
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Monitoring urban land cover and vegetation change by multi-temporal remote sensing information 被引量:10
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作者 DU Peijun LI Xingli +2 位作者 CAO Wen LUO Yan ZHANG Huapeng 《Mining Science and Technology》 EI CAS 2010年第6期922-932,共11页
In order to analyze changes in human settlement in Xuzhou city during the past 20 years, changes in land cover and vegetation were investigated based on multi-temporal remote sensing Landsat TM images. We developed a ... In order to analyze changes in human settlement in Xuzhou city during the past 20 years, changes in land cover and vegetation were investigated based on multi-temporal remote sensing Landsat TM images. We developed a hierarchical classifier system that uses different feature inputs for specific classes and conducted a classification post-processing approach to improve its accuracy. From our statistical analysis of changes in urban land cover from 1987 to 2007, we conclude that built-up land areas have obviously increased, while farmland has seen in a continuous loss due to urban growth and human activities. A NDVI difference approach was used to extract information on changes in vegetation. A false change information elimination approach was developed based on prior knowledge and statistical analysis. The areas of vegetation cover have been in continuous decline over the past 20 years, although some measures have been adopted to protect and maintain urban vegetation. Given the stability of underground coal exploitation since 1990s, urban growth has become the major driving force in vegetation loss, which is different from the vegetation change driven by coal exploitation mainly before 1990. 展开更多
关键词 urban settlement land cover change VEGETATION hierarchical classifier system URBANIZATION NDVI NDVI difference urban remote sensing
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Experiment and simulation on the pyrite removal from the recirculating load of pulverizer with a dilute phase gas-solid fluidized bed 被引量:6
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作者 Wang Shuai He Yaqun +2 位作者 He Jingfeng Ge Linhan Liu Qing 《International Journal of Mining Science and Technology》 SCIE EI 2013年第2期302-306,共5页
In order to reduce the energy consumption and subsequent air pollution of coal-fired power station, based on the analysis to size and density distribution of particles from the recirculating load of the classifier of ... In order to reduce the energy consumption and subsequent air pollution of coal-fired power station, based on the analysis to size and density distribution of particles from the recirculating load of the classifier of pulverizer, the separation experiment on sampling material from power plant with a dilute phase fluidized bed to remove pyrite and other minerals and numerical simulation on the separation process were done. The results show that the minimum fluidization velocity is 1.62 cm/s. Pyrite and other minerals in the material are separated. Ash of the upper and bottom layer material account for 33.34% and 73.42% respectively and sulfur content occupy 1.12% and 8.96% respectively. Scanning electron microscopy and spectroscopy tests show that sulfur in the bottom material exist in the form of pyrite. Numerical simulation on the flow field form of the dilute phase separation bed with gas-solid two phase and particle motion verifies the experimental results. 展开更多
关键词 Pulverizer Recirculating load of classifier Dilute phase fluidized bed Pyrite Numerical simulation
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Texture image classification using multi fractal dimension 被引量:1
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作者 LIU Zhuo-fu and SANG En-fang School of Underwater Acoustic Engineering, Harbin Engineering University, Harbin 150001 , China 《Journal of Marine Science and Application》 2003年第2期76-81,共6页
This paper presents a supervised classification method of sonar image, which takes advantages of both multi-fractal theory and wavelet analysis. In the process of feature extraction, image transformation and wavelet d... This paper presents a supervised classification method of sonar image, which takes advantages of both multi-fractal theory and wavelet analysis. In the process of feature extraction, image transformation and wavelet decomposition are combined and a feature set based on multi-fractal dimension is obtained. In the part of classifier construction, the Learning Vector Quantization (LVQ) network is adopted as a classifier. Experiments of sonar image classification were carried out with satisfactory results, which verify the effectiveness of this method. 展开更多
关键词 wavelet analysis multi-fractal dimension sonar image classification TEXTURE LVQ classifier
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