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1.
深度卷积神经网络(convolutional neural networks, CNN)作为特征提取器(feature extractor, CNN--FE)已被广泛应用于许多领域并获得显著成功. 根据研究评测可知CNN--FE具有大量参数, 这大大限制了CNN--FE在如智能手机这样的内存有限的设备上的应用. 本文以AlexNet卷积神经网络特征提取器为研究对象, 面向图像分类问题, 在保持图像分类性能几乎不变的情况下减少CNN--FE模型参数量. 通过对AlexNet各层参数分布的详细分析, 作者发现其全连接层包含了大约99%的模型参数, 在图像分类类别较少的情况, AlexNet提取的特征存在冗余. 因此, 将CNN--FE模型压缩问题转化为深度特征选择问题, 联合考虑分类准确率和压缩率, 本文提出了一种新的基于互信息量的特征选择方法, 实现CNN--FE模型压缩. 在公开场景分类数据库以及自建的无线胶囊内窥镜(wireless capsule endoscope, WCE)气泡图片数据库上进行图像分类实验. 结果表明本文提出的CNN--FE模型压缩方法减少了约83%的AlexNet模型参数且其分类准确率几乎保持不变.  相似文献   

2.
垃圾邮件处理中LDA特征选择方法   总被引:1,自引:0,他引:1       下载免费PDF全文
垃圾邮件处理是一项长期研究课题,越来越多的文本分类技术被移植到垃圾邮件处理应用当中。LDA(Latent Dirichlet Allocation)等topic模型在自动摘要、信息获取和其他离散数据应用中受到越来越多的关注。将LDA模型作为一种特征选择方法,引入垃圾邮件处理应用中。将LDA特征选择方法与质心+KNN分类器结合,得到简单的测试用垃圾邮件过滤器。初步实验结果表明,基于LDA的特征选择方法优于通常的IG、MI特征选择方法;测试过滤器的过滤性能与其他过滤器相当。  相似文献   

3.
基于BP神经网络和特征选择的入侵检测模型   总被引:2,自引:1,他引:2       下载免费PDF全文
提出了一种基于后向传播神经网络和特征选择的入侵检测模型。通过使用该模型对经过特征提取后的攻击数据的训练学习,可以有效地识别各种入侵。在经典的KDD 1999数据集上的测试说明:该模型与传统的入侵检测模型相比,能够轻便、高效地对攻击模式进行训练学习,从而正确有效地检测网络攻击。  相似文献   

4.
针对传统卷积神经网络训练过程中,对于全量样本直接进行特征提取会带有过多非关键区分特征使得训练存在模型过拟合、训练收敛慢等问题,提出一种基于典型样本的卷积神经网络TSBCNN。通过部分典型样本生成强化因子指导修正CNN训练,在特征提取阶段更加注重关键区分特征部分,有目的地降低网络训练过程中对非关键特征的学习,有效提高网络训练效果。大量实验结果表明,TSBCNN较传统CNN网络收敛速度和分类准确率有所提高,在一定程度上有效减少过拟合。  相似文献   

5.
Feature selection and classification techniques have been studied independently without considering the interaction between both procedures, which leads to a degraded performance. In this paper, we present a new neural network approach, which is called an algorithm learning based neural network (ALBNN), to improve classification accuracy by integrating feature selection and classification procedures. In general, a knowledge-based artificial neural network operates on prior knowledge from domain experience, which provides it with better starting points for the target function and leads to better classification accuracy. However, prior knowledge is usually difficult to identify. Instead of using unknown background resources, the proposed method utilizes prior knowledge that is mathematically calculated from the properties of other learning algorithms such as PCA, LARS, C4.5, and SVM. We employ the extreme learning machine in this study to help obtain better initial points faster and avoid irrelevant time-consuming work, such as determining architecture and manual tuning. ALBNN correctly approximates a target hypothesis by both considering the interaction between two procedures and minimizing individual procedure errors. The approach produces new relevant features and improves the classification accuracy. Experimental results exhibit improved performance in various classification problems. ALBNN can be applied to various fields requiring high classification accuracy.  相似文献   

6.
Radio-frequency fingerprinting is a technique for the authentication and identification of wireless devices using their intrinsic physical features and an analysis of the digitized signal collected during transmission. The technique is based on the fact that the unique physical features of the devices generate discriminating features in the transmitted signal, which can then be analyzed using signal-processing and machine-learning algorithms. Deep learning and more specifically convolutional neural networks (CNNs) have been successfully applied to the problem of radio-frequency fingerprinting using a spectral domain representation of the signal. A potential problem is the large size of the data to be processed, because this size impacts on the processing time during the application of the CNN. We propose an approach to addressing this problem, based on dimensionality reduction using feature-selection algorithms before the spectrum domain representation is given as an input to the CNN. The approach is applied to two public data sets of radio-frequency devices using different feature-selection algorithms for different values of the signal-to-noise ratio. The results show that the approach is able to achieve not only a shorter processing time; it also provides a superior classification performance in comparison to the direct application of CNNs.  相似文献   

7.
提出一种改进的神经网络属性选择方法。该方法用敏感度分析法对初始属性集中的属性进行排序,剔除次要属性实现降维,用BP神经网络进行属性选择以找到最小属性集。仿真结果表明该方法效果良好。  相似文献   

8.

The detection of manmade disasters particularly fire is valuable because it causes many damages in terms of human lives. Research on fire detection using wireless sensor network and video-based methods is a very hot research topic. However, the WSN based detection model need fire happens and a lot of smoke and fire for detection. Similarly, video-based models also have some drawbacks because conventional algorithms need feature vectors and high rule-based models for detection. In this paper, we proposed a fire detection method which is based on powerful machine learning and deep learning algorithms. We used both sensors data as well as images data for fire prevention. Our proposed model has three main deep neural networks i.e. a hybrid model which consists of Adaboost and many MLP neural networks, Adaboost-LBP model and finally convolutional neural network. We used Adaboost-MLP model to predict the fire. After the prediction, we proposed two neural networks i.e. Adaboost-LBP model and convolutional neural network for detection of fire using the videos and images taken from the cameras installed for the surveillance. Adaboost-LBP model is to generate the ROIs from the image where emergencies exist Our proposed model results are quite good, and the accuracy is almost 99%. The false alarming rate is very low and can be reduced more using further training.

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9.
应用信噪比和概率神经网络的方法,结合实验数据,提出胃癌分类模型。它是利用已知信息对胃癌样本进行分析和判别。其方法是首先对数据进行分类信息指数信噪比分析,根据分类信息指数信噪比大小排序,然后采用特征向量递增的方法,将特征向量输入概率神经网络进行分析,采用留一法对PNN训练和检测,找出训练效果最好的特征向量子集。这种模型用MATLAB软件实现,具有可操作性,可推广到其它相应的疾病辅助诊断中去。  相似文献   

10.
为解决深度卷积神经网络模型占用存储空间较大的问题,提出一种基于K-SVD字典学习的卷积神经网络压缩方法。用字典中少数原子的线性组合来近似表示单个卷积核的参数,对原子的系数进行量化,存储卷积核参数时,只须存储原子的索引及其量化后的系数,达到模型压缩的目的。在MNIST数据集上对LeNet-C5和CIFAR-10数据集上对DenseNet的压缩实验结果表明,在准确率波动不足0.1%的情况下,将网络模型占用的存储空间降低至12%左右。  相似文献   

11.
In most cases, the conventional pencil-drawing-synthesized methods were in terms of geometry and stroke, or only used classic edge detection method to extract image edge characters. In this paper, we propose a new method to produce pencil drawing from natural image. The synthesized result can not only generate pencil sketch drawing, but also can save the color tone of natural image and the drawing style is flexible. The sketch and style are learned from the edge of original natural image and one pencil image exemplar of artist’s work. They are accomplished through using the convolutional neural network feature maps of a natural image and an exemplar pencil drawing style image. Large-scale bound-constrained optimization (L-BFGS) is applied to synthesize the new pencil sketch whose style is similar to the exemplar pencil sketch. We evaluate the proposed method by applying it to different kinds of images and textures. Experimental results demonstrate that our method is better than conventional method in clarity and color tone. Besides, our method is also flexible in drawing style.  相似文献   

12.
《国际计算机数学杂志》2012,89(7):1105-1117
A neural network ensemble is a learning paradigm in which a finite collection of neural networks is trained for the same task. Ensembles generally show better classification and generalization performance than a single neural network does. In this paper, a new feature selection method for a neural network ensemble is proposed for pattern classification. The proposed method selects an adequate feature subset for each constituent neural network of the ensemble using a genetic algorithm. Unlike the conventional feature selection method, each neural network is only allowed to have some (not all) of the considered features. The proposed method can therefore be applied to huge-scale feature classification problems. Experiments are performed with four databases to illustrate the performance of the proposed method.  相似文献   

13.
Radial basis neural networks are excellent candidates for selecting relevant features in pattern recognition problems. By a slight change in the traditional three-layer architecture of a radial basis neural network, we can obtain a quantitative method, which allows us to get a ranking within the features. We present a new neural network concept, combining at the same time two different skills: classification and detection of relevant features in the input vector.  相似文献   

14.
Hepatic fibrosis represents the principal pointer to the development of liver diseases. The correct evaluation of its degree, based on both recent non-invasive procedures and machine learning models, is of current major concern. One of the latest medical imaging methodologies for assessing it is the Fibroscan, supported by biochemical and clinical examinations. Since the complex interaction between the Fibroscan stiffness indicator and the biochemical and clinical results is hard to be manually managed towards the liver fibrosis stadialization, well-performing machine learning algorithms have been proposed to support an automatic diagnosis. We propose in this paper a tandem feature selection mechanism and evolutionary-driven neural network as a computer-based support for liver fibrosis stadialization in chronic hepatitis C. A synergetic system, based on both specific statistical tools and the sensitivity analysis provided by neural networks is used for reducing the dimension of the database from twenty-five to just six attributes. An evolutionary-trained neural network is developed afterwards for the classification of the liver fibrosis stages. The tandem approach is direct and simple, resulting from embedding the feature selection system into the method structure, in order to dynamically concentrate the search only on the most relevant attributes. Experimental results and a thorough statistical analysis clearly demonstrated the efficiency of the proposed intelligent system in comparison with other machine learning techniques reported in literature.  相似文献   

15.
Wang  Zixi  Li  Fan 《Multimedia Tools and Applications》2021,80(2):2441-2460
Multimedia Tools and Applications - Video coding is one of the key technologies of visual sensors. As the state-of-art video coding standard, High Efficiency Video Coding (HEVC) achieves a...  相似文献   

16.
Feature selection is a useful pre-processing technique for solving classification problems. The challenge of solving the feature selection problem lies in applying evolutionary algorithms capable of handling the huge number of features typically involved. Generally, given classification data may contain useless, redundant or misleading features. To increase classification accuracy, the primary objective is to remove irrelevant features in the feature space and to correctly identify relevant features. Binary particle swarm optimization (BPSO) has been applied successfully to solving feature selection problems. In this paper, two kinds of chaotic maps—so-called logistic maps and tent maps—are embedded in BPSO. The purpose of chaotic maps is to determine the inertia weight of the BPSO. We propose chaotic binary particle swarm optimization (CBPSO) to implement the feature selection, in which the K-nearest neighbor (K-NN) method with leave-one-out cross-validation (LOOCV) serves as a classifier for evaluating classification accuracies. The proposed feature selection method shows promising results with respect to the number of feature subsets. The classification accuracy is superior to other methods from the literature.  相似文献   

17.
林伟铭  高钦泉  杜民 《计算机应用》2017,37(12):3504-3508
针对阿尔兹海默症(AD)通常会导致海马体区域萎缩的现象,提出一种使用卷积神经网络(CNN)对脑部磁共振成像(MRI)的海马体区域进行AD识别的方法。测试数据来自ADNI数据库提供的188位患者和229位正常人的脑部MRI图像。首先,将所有脑图像进行颅骨剥离,并配准到标准模板;其次,使用线性回归进行脑部萎缩的年龄矫正;然后,经过预处理后,从每个对象的3D脑图像的海马体区域提取出多幅2.5D的图像;最后,使用CNN对这些图像进行训练和识别,将同一个对象的图像识别结果用于对该对象的联合诊断。通过多次十折交叉验证方式进行实验,实验结果表明所提方法的平均识别准确率达到88.02%。与堆叠自动编码器(SAE)方法进行比较,比较结果表明,所提方法在仅使用MRI进行诊断的情况下效果比SAE方法有较大提高。  相似文献   

18.
随着智能设备的不断出现,图像数量急速增加,但是很多图像因为没有被标注所以未被充分利用.为了能够使该问题得到较好解决,提出了基于LDA和卷积神经网络的半监督图像标注方法.首先把图像训练集中的所有文字信息放入LDA中,生成图像的文字标注词;然后使用卷积神经网络获得图像的高层视觉特征,同时用加入注意力机制和修改损失函数的方法...  相似文献   

19.
林荣强  李鸥  李青  李林林 《计算机应用》2014,34(11):3206-3209
针对网络流量特征选择过程中存在的样本标记瓶颈问题,以及现有半监督方法无法选择强相关的特征的不足,提出一种基于类标记扩展的多类半监督特征选择(SFSEL)算法。该算法首先从少量的标记样本出发,通过K-means算法对未标记样本进行类标记扩展;然后结合基于双重正则的支持向量机(MDrSVM)算法实现多类数据的特征选择。与半监督特征选择算法Spectral、PCFRSC和SEFR在Moore数据集进行了对比实验,SFSEL得到的分类准确率和召回率明显都要高于其他算法,而且SFSEL算法选择的特征个数明显少于其他算法。实验结果表明: SFSEL算法能够有效地提高所选特征的相关性,获取更好的网络流量分类性能。  相似文献   

20.
行人再识别中,为了获得基于突出性颜色名称的颜色描述(SCNCD)特征对于光照变化较好的鲁棒性,提出了融合SCNCD特征和对于视角变化鲁棒性高的局部最大出现概率(LOMO)表观特征;为了获得图像的结构信息,将图像划分为多个重叠块,并提取块特征;针对神经网络容易陷入局部极小值,且收敛速度慢的问题,引入动量项.经过公用VIPeR数据库和PRID450s数据测试后,实验结果表明:融合后的特征的识别能力明显高于原特征的识别能力,且改进后的神经网络收敛速度明显提高.  相似文献   

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