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1.
提出了一种新的手写数字识别方法,利用传统的Radon变换,找到了一种新的旋转不变特征,最后采用BP神经网络分类器进行分类。实验表明,该方法不仅具有93.89%的高识别率,而且对字符旋转具有很好的鲁棒性。  相似文献   

2.
基于组合分类器的自由手写体数字识别方法   总被引:1,自引:1,他引:0  
自由手写体数字识别广泛应用于信息录入和文本识别中。基于组合分类器实现手写数字的识别,克服了单因子识别的局限性,识别中使用距离法和改进的BP神经网络方法,以多种特征向量作为分类器的输入,以举手法则确定识别输出。实验证明,该系统具有较高的识别率和极低的误识率,有令人鼓舞的应用价值。  相似文献   

3.
Asifullah  Syed Fahad  Abdul  Tae-Sun   《Pattern recognition》2008,41(8):2594-2610
We present an innovative scheme of blindly extracting message bits when a watermarked image is distorted. In this scheme, we have exploited the capabilities of machine learning (ML) approaches for nonlinearly classifying the embedded bits. The proposed technique adaptively modifies the decoding strategy in view of the anticipated attack. The extraction of bits is considered as a binary classification problem. Conventionally, a hard decoder is used with the assumption that the underlying distribution of the discrete cosine transform coefficients do not change appreciably. However, in case of attacks related to real world applications of watermarking, such as JPEG compression in case of shared medical image warehouses, these coefficients are heavily altered. The sufficient statistics corresponding to the maximum likelihood based decoding process, which are considered as features in the proposed scheme, overlap at the receiving end, and a simple hard decoder fails to classify them properly. In contrast, our proposed ML decoding model has attained highest accuracy on the test data. Experimental results show that through its training phase, our proposed decoding scheme is able to cope with the alterations in features introduced by a new attack. Consequently, it achieves promising improvement in terms of bit correct ratio in comparison to the existing decoding scheme.  相似文献   

4.
Identification of more than three perfumes is very difficult for the human nose. It is also a problem to recognize patterns of perfume odor with an electronic nose that has multiple sensors. For this reason, a new hybrid classifier has been presented to identify type of perfume from a closely similar data set of 20 different odors of perfumes. The structure of this hybrid technique is the combination of unsupervised fuzzy clustering c-mean (FCM) and supervised support vector machine (SVM). On the other hand this proposed soft computing technique was compared with the other well-known learning algorithms. The results show that the proposed hybrid algorithm’s accuracy is 97.5% better than the others.  相似文献   

5.
支持向量机和人工神经网络是人工智能方法的两个分支,详细介绍了支持向量机和人工神经网络原理。建立了网络安全评估指标体系,将支持向量机和人工神经网络同时应用于网络安全风险评估的过程中,通过实例比较了两者的评估效果,结果表明了支持向量机在小样本情况下分类正确率普遍高于人工神经网络,具有较好的分类能力和泛化能力;同时在训练时间上也有绝对的优势。实践证实了支持向量机用于网络安全风险评估的有效性和优越性。  相似文献   

6.
朱小川 《计算机仿真》2012,29(3):266-269
研究软件衰退问题,软件衰退数据存在大量噪声,传统预测方法难以消除噪声,预测精度低。为提高软件衰退预测精度,提出一种小波支持向量机的软件衰退预测方法。首先对收集软件衰退预测数据进行归一化处理,而后采用小波分析对数据进行分解,分解成多信尺度,而后采用支持向量机对软件衰退数据各个尺度系数分别进行预测,最后采用小波分析对各尺度系数预测结果进行重构,得到软件衰退预测的最终结果。仿真结果表明,相对传统预测方法,小波支持向量机提高了软件衰退预测精度,能够很好地预测软件衰退趋势。  相似文献   

7.
基于支持向量机算法的气体识别研究   总被引:1,自引:0,他引:1  
利用多传感器或者传感器阵列,同时,结合神经网络技术来进行气体识别和定量分析研究已成为目前传感器领域的一个研究热点。介绍了一种在该领域还没有引起足够重视的算法———支持向量机算法(SVM)。利用该算法,结合多传感器技术,对 3种不同体积分数的有机溶剂进行了识别研究,并取得了较好的识别效果,证明了该算法在气体识别领域具有相当大的研究价值。  相似文献   

8.
尚兴宏  尚曦乐  章静  钱焕延 《计算机科学》2013,40(Z6):327-329,343
无线传感器网络节点发生故障不仅消耗节点的能量和网络带宽,甚至会造成网络瘫痪。在分析无线传感器网络节点故障类别的基础上,分别使用相关向量机、支持向量机等算法对其进行研究,并用节点的特征值及相应的故障类型训练相关向量机及支持向量机的分类器。仿真结果表明,相关向量机比支持向量机和人工神经网络有更高的诊断精度。  相似文献   

9.
r-SVR中参数r与输入噪声间线性反比关系的仿真研究   总被引:3,自引:0,他引:3  
为研究r范数-支持向量回归机r-SVR的鲁棒性,验证r-SVR中参数r与输入噪声方差之间的近似反比线性关系,对r-SVR进行了仿真.推导出了作为仿真的依据的r-SVR的解的形式和对其进行求解的牛顿迭代公式.仿真结果显示:输入噪声为高斯分布时,r-SVR中参数r与输入噪声方差之间存在近似线性反比关系;这一关系曲线随着信噪比增加而斜率减小、整个曲线下移.这一结果印证和丰富了现前的理论推导结果,为在已知输入高斯噪声方差时合理地选择r提供了更可信的依据.  相似文献   

10.
The pulse-coupled neural network (PCNN) has been widely used in image processing. The outputs of PCNN represent unique features of original stimulus and are invariant to translation, rotation, scaling and distortion, which is particularly suitable for feature extraction. In this paper, PCNN and intersecting cortical model (ICM), which is a simplified version of PCNN model, are applied to extract geometrical changes of rotation and scale invariant texture features, then an one-class support vector machine based classification method is employed to train and predict the features. The experimental results show that the pulse features outperform of the classic Gabor features in aspects of both feature extraction time and retrieval accuracy, and the proposed one-class support vector machine based retrieval system is more accurate and robust to geometrical changes than the traditional Euclidean distance based system.  相似文献   

11.
基于方向线素特征的孟加拉手写数字识别   总被引:1,自引:0,他引:1       下载免费PDF全文
林颖  吕岳 《计算机工程》2009,35(15):185-186
根据孟加拉数字的特点,将方向线素特征应用于孟加拉手写数字识另怕g特征提取,并辅以端点和交叉点特征,采用BP神经网络作分类器进行识别。利用从实际盂加拉信封图像中采集到的手写体数字作为样本进行实验,结果表明,该方法的识别率和可靠性分别达到97.63%和98.77%。  相似文献   

12.
Accurate rainfall-runoff modeling during typhoon events is an essential task for natural disaster reduction. In this study, a novel hybrid model which integrates the outputs of physically based hydrologic modeling system into support vector machine is developed to predict hourly runoff discharges in Chishan Creek basin in southern Taiwan. Seven storms (with a total of 1200 data sets) are used for model calibration (training) and validation. Six statistical indices (mean absolute error, root mean square error, correlation coefficient, error of time to peak discharge, error of peak discharge, and coefficient of efficiency) are employed to assess prediction performance. Overall, superiority of the present approach especially for a longer (6-h) lead time prediction is revealed through a systematic comparison among three individual methods (i.e., the physically based hydrologic model, artificial neural network, and support vector machine) as well as their two hybrid combinations. Besides, our analysis and in-depth discussions further clarify the roles of physically based and data-driven components in the proposed framework.  相似文献   

13.
One of the research problems investigated these days is early fault detection. To this end, advanced signal processing algorithms are employed. The present paper makes an attempt at early fault detection in a gearbox. In order to evaluate its technical condition, artificial neural networks were used. Early fault detection based on support vector machines is a relatively new and rarely employed method for evaluating condition of machines, particularly gearboxes. The available literature offers very promising results of using this method. In order to compare the obtained results, a multilayer perceptron network was created. Such standard neural network ensures high effectiveness. The vibration signal obtained from a sensor is seldom a material for direct analysis. First, it needs to be processed to bring out the informative part of the signal. To this end, a wavelet transform was used. The presented results concern both a “raw” vibration signal and processed one, investigated for two neural networks. The wavelet transform has proved to improve significantly the accuracy of condition evaluation and the results obtained by the two networks are consistent with one another.  相似文献   

14.
针对脱机手写体汉字特点,给出一种采用模糊支持向量机粗分类的方法。根据小波分解像素密度特征,利用模糊支持向量机对汉字进行粗分类。细分类识别提取外围特征,同时融合小波多网格特征,采用一对多算法进行细识别。仿真实验表明,该方法有较高识别率。  相似文献   

15.
Quantitative simulation of solar radiation is essential for understanding climate change 0n the Loess Plateau, Many machine learning methods were developed to estimate solar radiation well, but different machine learning methods have different simulation accuracy in different regions, In order to achieve optimal simulation of solar radiation on the Loess Plateau, this provides more higher precision solar radiation data for crop models, hydrological models, and climate change models. In this study, three machine learning methods, including Random Forest (RF), Artificial Neural Network (ANN) and Support Vector Machine (SVM), were applied to estimate solar radiation on the Loess Plateau, three machine learning methods were trained using ground measurements at fourteen radiation sites from 2003 to 2009 and ten radiation sites from 2010 to 2016 and corresponding parameter pressure, cloud fraction, cloud optical thickness, ozone, precipitation water vapor and DEM, slope, and aspect to train the three model, The solar radiation estimates based on three machine learning methods were evaluated using ground measurements at four radiation sites from 2010 to 2016. The validation results show that the RF model has the best simulation effect on the Loess Plateau and surrounding areas. The average deviation is -0.17 MJ·m-2, the root mean square error is 1.48 MJ·m-2, and has a good fit of 0.96. The results show that combined RF model and meteorological data and remote sensing data can effectively solve the problem about solar radiation simulation on the non-radiation observation area of the Loess Plateau, which is of great significance to the research of regional solar radiation.  相似文献   

16.
17.
定量模拟太阳辐射对认识黄土高原区气候变化至关重要,现有研究表明机器学习可以很好地模拟太阳辐射,但不同的机器学习法在不同区域模拟精度不同,为了实现黄土高原区太阳辐射数据的最优模拟,从而为农作物模型、水文模型以及气候变化模型提供精度更高的太阳辐射数据。基于随机森林(RF,Random Forest)、人工神经网络(ANN,Artificial Neural Network)和支持向量机(SVM,Support Vector Machine)3种机器学习法来模拟黄土高原地区的太阳辐射并对这3种算法进行比较研究,选取了2003~2009年14个辐射站点和2010~2016年10个辐射站点的实测数据和对应参数气压、云量、云光学厚度、臭氧、可降水水汽以及DEM、坡度、坡向作为模型的训练数据,随机选取2010~2016年4个辐射站点的太阳辐射实测数据对模拟结果进行验证。验证结果表明:RF模型在黄土高原及周边地区的模拟效果最优,平均偏差(MBE)为-0.17 MJ·m-2,均方根误差(RMSE)为1.48 MJ·m-2,拟合优度达到0.96。研究结果表明:RF模型与气象数据及遥感数据结合能够有效解决黄土高原无辐射观测区的太阳辐射模拟问题,对区域太阳辐射的研究具有重要意义。  相似文献   

18.
基于支持向量机的AdaBoost人脸检测方法   总被引:4,自引:3,他引:1  
人脸的检测与识别技术因其巨大的应用价值及市场潜力,引起各方面的关注,已经成为计算机视觉领域的研究热点.介绍了一种基于支持向量机(SVM)的AdaBoost人脸检测方法.与原有的AdaBoost算法相比,AdaBoostSVM算法通过设置核参数σ的最小值,并自适应地调整σ值来解决AdaBoost算法分类器训练中的过学习问题.该方法降低了复杂性,增强了推广性.实验结果证明,对于人脸模型具有较好的检测效果,并且比单纯运用AdaBooet算法具有更高的正确检测率.  相似文献   

19.
廉飞宇  付麦霞  张元 《计算机工程与设计》2006,27(21):4033-4035,4042
将支持向量机(SVM)引入到复杂条件下运动车辆牌照字符的识别中。回顾了车牌识别研究的现状,简要介绍了SVM的基本原理,比较了SVM算法和神经网络算法在车牌字符识别上的优劣;提出了采用基于先验知识的二叉树结构组合多个二值分类支持向量机来解决车牌字符的多类识别问题。在实验中采用了LibSVM训练软件,针对车牌汉字的小字符集进行了仿真,同时与神经网络分类方法进行了比较。实验结果表明该方法的汉字识别率较高,在小字符集车牌汉字识别中具有较强的实用性。  相似文献   

20.
Breast cancer continues to be a significant public health problem in the world. Early detection is the key for improving breast cancer prognosis. Mammogram breast X-ray is considered the most reliable method in early detection of breast cancer. However, it is difficult for radiologists to provide both accurate and uniform evaluation for the enormous mammograms generated in widespread screening. Micro calcification clusters (MCCs) and masses are the two most important signs for the breast cancer, and their automated detection is very valuable for early breast cancer diagnosis. The main objective is to discuss the computer-aided detection system that has been proposed to assist the radiologists in detecting the specific abnormalities and improving the diagnostic accuracy in making the diagnostic decisions by applying techniques splits into three-steps procedure beginning with enhancement by using Histogram equalization (HE) and Morphological Enhancement, followed by segmentation based on Otsu's threshold the region of interest for the identification of micro calcifications and mass lesions, and at last classification stage, which classify between normal and micro calcifications ‘patterns and then classify between benign and malignant micro calcifications. In classification stage; three methods were used, the voting K-Nearest Neighbor classifier (K-NN) with prediction accuracy of 73%, Support Vector Machine classifier (SVM) with prediction accuracy of 83%, and Artificial Neural Network classifier (ANN) with prediction accuracy of 77%.  相似文献   

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