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1.
Breast cancer is a leading cancer affecting women worldwide. Mammography is a scanning procedure involvingX‐rays of the breast. It causes discomfort and may cause high incidence of false negatives. Breast thermography is a new screening method of breast that helps in the early detection of cancer. It is a non‐invasive imaging procedure that captures the infrared heat radiating off from the breast surface using an infrared camera. The main objective of this work is to evaluate the use of higher order spectral features extracted from thermograms in classifying normal and abnormal thermograms. For this purpose, we extracted five higher order spectral features and used them in a feed‐forward artificial neural network (ANN) classifier and a support vector machine (SVM). Fifty thermograms (25 each of normal and abnormal) were used for analysis.SVM presented a good sensitivity of 76% and specificity of 84%, and theANN classifier demonstrated higher values of sensitivity (92%) and specificity (88%). The proposed system, therefore, shows great promise in automatic classification of normal and abnormal breast thermograms without the need for subjective interpretation.  相似文献   

2.
The dynamic model of lateral inhibition network and it is application   总被引:1,自引:0,他引:1  
Breast cancer is the major cause of cancer deaths in women today and it is the most common type of cancer in women. Many sophisticated algorithm have been proposed for classifying breast cancer data. This paper presents some experiments for classifying breast cancer tumor and proposes the use local linear wavelet neural network for breast cancer recognition by training its parameters using Recursive least square (RLS) approach to improve its performance. The difference of the local linear wavelet network with conventional wavelet neural network (WNN) is that the connection weights between hidden layer and output layer of conventional WNN are replaced by a local linear model. The result quality has been estimated and compared with other experiments. Results on extracted breast cancer data from University of Wisconsin Hospital Madison show that the proposed approach is very robust, effective and gives better classification.  相似文献   

3.
周涛  蒋芸  王勇  张国荣  王明芳  明利特 《计算机应用》2010,30(10):2857-2860
为了提高乳腺癌早期诊断的准确率,将小波理论与神经网络理论相结合提出改进的小波神经网络算法。将经过预处理的医学图像提取特征值,然后利用基于改进的小波神经网络算法的分类器对医学图像进行分类。通过实验表明此分类器具有较高的分类精度,是有效和可行的;与单独使用后向传播神经网络算法相比分类效果也得到了改善。  相似文献   

4.
One of the fast-growing disease affecting women’s health seriously is breast cancer. It is highly essential to identify and detect breast cancer in the earlier stage. This paper used a novel advanced methodology than machine learning algorithms such as Deep learning algorithms to classify breast cancer accurately. Deep learning algorithms are fully automatic in learning, extracting, and classifying the features and are highly suitable for any image, from natural to medical images. Existing methods focused on using various conventional and machine learning methods for processing natural and medical images. It is inadequate for the image where the coarse structure matters most. Most of the input images are downscaled, where it is impossible to fetch all the hidden details to reach accuracy in classification. Whereas deep learning algorithms are high efficiency, fully automatic, have more learning capability using more hidden layers, fetch as much as possible hidden information from the input images, and provide an accurate prediction. Hence this paper uses AlexNet from a deep convolution neural network for classifying breast cancer in mammogram images. The performance of the proposed convolution network structure is evaluated by comparing it with the existing algorithms.  相似文献   

5.
Breast cancer is known as one of the major causes of mortality among women. Breast cancer can be treated with better patient outcomes and significantly lower costs if it is detected early. Digital mammograms are the type of medical images most often used, and which are the most reliable, for the detection of breast cancer. The presence of microcalcification clusters in mammograms contributes to evidence for the detection of early stages of cancer. In this paper, a bi-modal artificial neural network (ANN) based breast cancer classification system is proposed. The microcalcifications are extracted with adaptive neural networks that are trained with cancer/malignant and normal/benign breast digital mammograms of both cranio caudal (CC) and medio-latral oblique (MLO) views. The performance of the networks is evaluated using receiver operating characteristic (ROC) curve analysis. Sensitivity–specificity of 98.0–100.0 for the CC view and 96.0–100.0 for the MLO view networks are recorded for 200 unseen digital database for screening mammography (DDSM) cases. The DDSM database, developed at the University of South Florida, is a resource for use by the mammographic image analysis research community. The OR logic is then used to fuse individual networks to get a best sensitivity–specificity of 100.0–100.0 for the ensemble. However, the overall sensitivity–specificity of the ANN ensemble is somewhat degraded at the expense of a robust or sensitive system, i.e., the probability to miss out a true positive case is minimized.  相似文献   

6.
Breast cancer is the major cause of cancer deaths in women today and it is the most common type of cancer in women. This paper presents some experiments for classifying breast cancer tumor and proposes the use of firefly algorithm (FA) to improve the performance of Local linear wavelet neural network. This work in fact uses FA to optimize the parameters of local linear wavelet neural network. The experiments were conducted on extracted breast cancer data from University of Winconsin Hospital, Madison. The result has been compared with a wide range of classifiers to evaluate its performance. The evaluations show that the proposed approach is very robust, effective and gives better correct classification as compared to other classifiers.  相似文献   

7.
组织病理学是临床上肿瘤诊断的金标准,直接关系到治疗的开展与预后的评估。来自临床的需求为组织病理诊断提出了质量与效率两个方面的挑战。组织病理诊断涉及大量繁重的病理切片判读任务,高度依赖医生的经验,但病理医生的培养周期长,人才储备缺口巨大,病理科室普遍超负荷工作。近年来出现的基于深度学习的组织病理辅助诊断方法可以帮助医生提高诊断工作的精度与速度,缓解病理诊断资源不足的问题,引起了研究人员的广泛关注。本文初步综述深度学习方法在组织病理学中的相关研究工作。介绍了组织病理诊断的医学背景,整理了组织病理学领域的主要数据集,重点介绍倍受关注的乳腺癌、淋巴结转移癌、结肠癌的病理数据及其分析任务。本文归纳了数据的存储与处理、模型的设计与优化以及小样本与弱标注学习这3项需要解决的技术问题。围绕这些问题,本文介绍了包括数据存储、数据预处理、分类模型、分割模型、迁移学习和多示例学习等相关研究工作。最后总结了面向组织病理学诊断的深度学习方法研究现状,并指出当下研究工作可能的改进方向。  相似文献   

8.
Breast cancer occurs when cells in the breast begin to grow out of control and invade nearby tissues or spread throughout the body. It is one of the leading causes of death in women. Cancer development appears to generate an increase in the temperature on the breast surface. The limitations of mammography as a screening modality, especially in young women with dense breasts, necessitated the development of novel and more effective screening strategies with high sensitivity and specificity. The aim of this study was to evaluate the feasibility of discrete thermal data (DTD) as a potential tool for the early detection of the breast cancer.Our protocol uses 1170, 16-sensor data collected from 54 individuals consisting of three different kinds of breast conditions: namely, normal, benign and cancerous breast. We compared two different kinds of neural network classifiers: the feedforward neural network and the radial basis function classifier. Temperature data from the 16 temperature sensors on the surface of the two breasts (eight sensors on each side) are fed as input to the classifiers. We demonstrated a sensitivity of 84% and 91% for these classifiers (feedforward and radial basis function, respectively) with a specificity of 100%. Our classifying systems are ready to run on large data sets.  相似文献   

9.
乳腺癌是易发生且致死率高的恶性肿瘤之一,及早诊断识别是降低致死率的关键.基于应用广泛的乳腺癌病理图像,结合卷积神经网络展开乳腺癌的识别研究.针对癌症图像细节和纹理特征难以识别的问题,采用插值处理将图像进行适当放大,以便研究分析.针对卷积神经网络参数庞大不易训练和不易硬件实现的问题,提出一种精简的5卷积层W型网络结构,具...  相似文献   

10.
Breast cancer is the most commonly occurring form of cancer in women. While mammography is the standard modality for diagnosis, thermal imaging provides an interesting alternative as it can identify tumors of smaller size and hence lead to earlier detection. In this paper, we present an approach to analysing breast thermograms based on image features and a hybrid multiple classifier system. The employed image features provide indications of asymmetry between left and right breast regions that are encountered when a tumor is locally recruiting blood vessels on one side, leading to a change in the captured temperature distribution. The presented multiple classifier system is based on a hybridisation of three computational intelligence techniques: neural networks or support vector machines as base classifiers, a neural fuser to combine the individual classifiers, and a fuzzy measure for assessing the diversity of the ensemble and removal of individual classifiers from the ensemble. In addition, we address the problem of class imbalance that often occurs in medical data analysis, by training base classifiers on balanced object subspaces. Our experimental evaluation, on a large dataset of about 150 breast thermograms, convincingly shows our approach not only to provide excellent classification accuracy and sensitivity but also to outperform both canonical classification approaches as well as other classifier ensembles designed for imbalanced datasets.  相似文献   

11.
为降低集成特征选择方法的计算复杂性,提出了一种基于粗糙集约简的神经网络集成分类方法。该方法首先通过结合遗传算法求约简和重采样技术的动态约简技术,获得稳定的、泛化能力较强的属性约简集;然后,基于不同约简设计BP网络作为待集成的基分类器,并依据选择性集成思想,通过一定的搜索策略,找到具有最佳泛化性能的集成网络;最后通过多数投票法实现神经网络集成分类。该方法在某地区Landsat 7波段遥感图像的分类实验中得到了验证,由于通过粗糙集约简,过滤掉了大量分类性能欠佳的特征子集,和传统的集成特征选择方法相比,该方法时  相似文献   

12.
为降低集成特征选择方法的计算复杂性,提出了一种基于粗糙集约简的神经网络集成分类方法。该方法首先通过结合遗传算法求约简和重采样技术的动态约简技术,获得稳定的、泛化能力较强的属性约简集;然后,基于不同约简设计BP网络作为待集成的基分类器,并依据选择性集成思想,通过一定的搜索策略,找到具有最佳泛化性能的集成网络;最后通过多数投票法实现神经网络集成分类。该方法在某地区Landsat 7波段遥感图像的分类实验中得到了验证,由于通过粗糙集约简,过滤掉了大量分类性能欠佳的特征子集,和传统的集成特征选择方法相比,该方法时间开销少,计算复杂性低,具有满意的分类性能。  相似文献   

13.
乳腺癌一直是影响女性健康最重要的问题之一,已经成为全球女性发病率最高的恶性肿瘤.近年来,利用机器学习和深度学习方法来诊断癌症已经成为发展较快的一个分支.通过使用逻辑回归模型(LR)、高斯核函数支持向量机(SVM)、前馈神经网络(MLP)对同一数据集进行预测,得出其中SVM迭代时间最短,前馈神经网络预测准确率最高.为了减...  相似文献   

14.
基于神经网络集成的肺癌早期诊断   总被引:3,自引:0,他引:3  
将病理性诊断与计算机技术相结合以实现肺癌的早期诊断,首先利用数字图像技术对肺癌穿刺样本进行处理,提出取形态和色度特征,然后通过一种二级集成结构和特殊的投票方式,用神经网络集成对细胞图象进行分析,实验和原型系统试用表明,方法的总误诊率和肺癌患者漏诊率均低于单一神经网络方法和常用的神经网络集成方法。  相似文献   

15.
Breast cancer has been becoming the main cause of death in women all around the world. An accurate and interpretable method is necessary for diagnosing patients with breast cancer for well-performed treatment. Nowadays, a great many of ensemble methods have been widely applied to breast cancer diagnosis, capable of achieving high accuracy, such as Random Forest. However, they are black-box methods which are unable to explain the reasons behind the diagnosis. To surmount this limitation, a rule extraction method named improved Random Forest (RF)-based rule extraction (IRFRE) method is developed to derive accurate and interpretable classification rules from a decision tree ensemble for breast cancer diagnosis. Firstly, numbers of decision tree models are constructed using Random Forest to generate abundant decision rules available. And then a rule extraction approach is devised to detach decision rules from the trained trees. Finally, an improved multi-objective evolutionary algorithm (MOEA) is employed to seek for an optimal rule predictor where the constituent rule set is the best trade-off between accuracy and interpretability. The developed method is evaluated on three breast cancer data sets, i.e., the Wisconsin Diagnostic Breast Cancer (WDBC) dataset, Wisconsin Original Breast Cancer (WOBC) dataset, and Surveillance, Epidemiology and End Results (SEER) breast cancer dataset. The experimental results demonstrate that the developed method can primely explain the black-box methods and outperform several popular single algorithms, ensemble learning methods, and rule extraction methods from the view of accuracy and interpretability. What is more, the proposed method can be popularized to other cancer diagnoses in practice, which provides an option to a more interpretable, more accurate cancer diagnosis process.  相似文献   

16.
一种基于聚类技术的选择性神经网络集成方法   总被引:11,自引:0,他引:11  
神经网络集成是一种很流行的学习方法,通过组合每个神经网络的输出生成最后的预测、为了提高集成方法的有效性,不仅要求集成中的个体神经网络具有很高的正确率,而且要求这些网络在输入空间产生不相关的错误.然而,在现有的众多集成方法中,大都采用将训练的所有神经网络直接进行组合以形成集成,实际上生成的这些神经网络可能具有一定的相关性.为了进一步提高神经网络间的差异性,一种基于聚类技术的选择性神经网络集成方法CLU_ENN被提出.在获得个体神经网络后,并不直接对这些神经网络集成,而是先应用聚类算法对这些神经网络模型聚类以获得差异较大的部分神经网络;然后由部分神经网络构成集成;最后,通过实验研究了CLU_ENN集成方法,与传统的集成方法Bagging相比,该方法取得了更好的效果。  相似文献   

17.
乳腺X线摄影技术是目前乳腺癌早期发现和诊断的重要手段。然而乳腺X线图像中肿块边缘模糊,分类相对困难,因此提升乳腺肿块的诊断精度从而及早预防和治疗仍是医学领域的一大挑战。针对乳腺肿块的特点,提出了一种结合密集卷积神经网络(DenseNet)和压缩激励(SE)模块的新网络(DSAMNet),该网络融合了二者优势,既加强特征重用,又实现特征提取过程中的特征重标定。根据SE模块嵌入DenseNet的不同位置,提出了模型SE-DenseNet-A、SE-DenseNet-B和SE-DenseNet-C。对SE-DenseNet的池化函数进行改进,提出了模型DSAMNet-A、DSAMNet-B和DSAMNet-C。综合不同结构和不同深度的网络模型在公开数据集CBIS-DDSM上进行训练和测试。实验结果表明,DSAMNet-B有更加优异的性能,其准确率比DenseNet模型的准确率提高了10.8%,AUC达到了0.929。  相似文献   

18.
《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   

19.
残差神经网络(residual neural network,ResNet)及其优化是深度学习研究的热点之一,在医学图像领域应用广泛,在肿瘤、心脑血管和神经系统疾病等重大疾病的临床诊断、分期、转移、治疗决策和靶区勾画方面取得良好效果。本文对残差神经网络的学习优化进行了总结:阐述了残差神经网络学习算法优化,从激活函数、损失函数、参数优化算法、学习衰减率、归一化和正则化技术等6方面进行总结,其中激活函数的改进方法主要有Sigmoid、tanh、ReLU、PReLU(parameteric ReLU)、随机化ReLU(randomized leaky ReLU,RReLU)、ELU(exponential linear units)、Softplus函数、NoisySoftplus函数以及Maxout共9种;损失函数主要有交叉熵损失、均方损失、欧氏距离损失、对比损失、合页损失、Softmax-Loss、L-Softmax Loss、A-Softmax Loss、L2 Softmax Loss、Cosine Loss、Center Loss和焦点损失共12种;学习率衰减总结了8种,即分段常数衰减、多项式衰减、指数衰减、反时限衰减、自然指数衰减、余弦衰减、线性余弦衰减和噪声线性余弦衰减;归一化算法有批量归一化和提出批量重归一化算法;正则化方法主要有增加输入数据、数据增强、早停法、L1正则化、L2正则化、Dropout和Dropout Connect共7种。综述了残差网络模型在医学图像疾病诊断中的应用研究,梳理了残差神经网络在肺部肿瘤、皮肤疾病、乳腺癌、大脑疾病、糖尿病和血液病等6种疾病诊断中的应用研究;对深度学习在医学图像未来发展进行了总结和展望。  相似文献   

20.
为快速准确地判断齿轮故障的类型,提出了小波包滤波和神经网络相结合进行齿轮故障分类的方法。介绍了小波包去噪的原理和神经网络的设计方法,对阈值算法和神经网络优化算法作了改进,得到了不含噪声的信号和准确的故障分类方法。仿真结果表明,基于小波包滤波的神经网络方法具有更高的准确性和稳定性,可以满足工业故障诊断的要求。  相似文献   

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