Segmentation of pulmonary nodules in chest radiographs is a particularly challenging task due to heavy noise and superposition of ribs,vessels,and other complicated anatomical structures in lung field. In this paper,a...Segmentation of pulmonary nodules in chest radiographs is a particularly challenging task due to heavy noise and superposition of ribs,vessels,and other complicated anatomical structures in lung field. In this paper,an adaptive order polynomial fitting based raycasting algorithm is proposed for pulmonary nodule segmentation in chest radiographs. Instead of detecting nodule edge points directly,the nodule intensity profiles are first fitted by using the polynomials with adaptively determined orders. Then,the edge positions are identified through analyzing the local minimum of the fitted curves.The performance of the proposed algorithm was evaluated over an image database with 148 nodule cases in chest radiographs that were collected from a variety of digital radiograph modalities. The preliminary results show the proposed algorithm can obtain a high rate of successful segmentations.展开更多
针对以频繁项集产生-规则产生为核心的两阶段关联规则挖掘,存在需要人工以先验知识指定最小支持度和最小置信度阈值的缺陷。本文提出以支持数和置信度为依据,采用曲线拟合技术,根据可决系数自动确定曲线的次数及对应多项式的算法AARM_BR...针对以频繁项集产生-规则产生为核心的两阶段关联规则挖掘,存在需要人工以先验知识指定最小支持度和最小置信度阈值的缺陷。本文提出以支持数和置信度为依据,采用曲线拟合技术,根据可决系数自动确定曲线的次数及对应多项式的算法AARM_BR(Adaptation Association Rule Mining Based on Determination Coefficient R^2),从而确定支持度和置信度阈值。在标准数据集Trolley和Groceries上进行关联规则挖掘实验,结果表明本算法更具有数据依赖性,在用户不具备先验知识的情况下,无须人为指定多项式阶次、支持度和置信度阈值的优点。展开更多
基金Innovation Program of Shanghai Municipal Education Commission,China(No.13YZ136)
文摘Segmentation of pulmonary nodules in chest radiographs is a particularly challenging task due to heavy noise and superposition of ribs,vessels,and other complicated anatomical structures in lung field. In this paper,an adaptive order polynomial fitting based raycasting algorithm is proposed for pulmonary nodule segmentation in chest radiographs. Instead of detecting nodule edge points directly,the nodule intensity profiles are first fitted by using the polynomials with adaptively determined orders. Then,the edge positions are identified through analyzing the local minimum of the fitted curves.The performance of the proposed algorithm was evaluated over an image database with 148 nodule cases in chest radiographs that were collected from a variety of digital radiograph modalities. The preliminary results show the proposed algorithm can obtain a high rate of successful segmentations.
文摘针对以频繁项集产生-规则产生为核心的两阶段关联规则挖掘,存在需要人工以先验知识指定最小支持度和最小置信度阈值的缺陷。本文提出以支持数和置信度为依据,采用曲线拟合技术,根据可决系数自动确定曲线的次数及对应多项式的算法AARM_BR(Adaptation Association Rule Mining Based on Determination Coefficient R^2),从而确定支持度和置信度阈值。在标准数据集Trolley和Groceries上进行关联规则挖掘实验,结果表明本算法更具有数据依赖性,在用户不具备先验知识的情况下,无须人为指定多项式阶次、支持度和置信度阈值的优点。