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Chinese Journal of Electronics 2019年第5期28卷 1000-1007页

作者： li Ruijing CHEN Houjin PENG Yahui li jupeng School of Electronic and Information Engineering Beijing Jiaotong University

Ultrasound computed tomography(USCT) is a promising approach for early breast cancer screening. Existing studies that estimate breast images using Waveform inversion(WI) methods utilize a Circular ultrasonic transducer element array(CUTA) to collect the measurement data. However, very accurate transducer element positioning and directivity are required for signal calibration in the hardware system of these studies,thereby causing difficulties in hardware *** purpose of this study is to estimate high-resolution USCT images using a WI method with a Square border ultrasonic transducer element array(SUTA), which reduces the difficulty of hardware manufacturing and creates accurate correspondence between the continuous and discrete forms of the transducer element ***, in this study, an SUTA is adopted to collect the measurement data of breast imaging using the WI method. A penalized least-squares optimization problem is constructed to obtain the numerical solution of a sound speed distribution. Computer simulations are conducted to compare images reconstructed from the measurement data that are collected using an SUTA and a *** performance is evaluated using a numerical breast phantom. Results suggest that the biases of the images reconstructed are less than 1% with the evenly distributed SUTA and 1% with the CUTA, under a noise condition.

关键词： Square border Breast cancer Image reconstruction Ultrasound computed tomography Waveform inversion

Comparison of Four Forward Models for Breast Imaging in Ultrasound Computed Tomography

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Chinese Journal of Electronics 2019年第4期28卷 805-816页

作者： li Ruijing CHEN Houjin PENG Yahui li jupeng School of Electronic and Information Engineering Beijing Jiaotong University

Ultrasound computed tomography(USCT) is considered to have great potential for breast cancer screening. Compared with ray-based methods,Waveform inversion(WI) methods obtain high spatial resolution images because they consider higher-order diffraction effects. For the WI method, considering more properties of the medium in a forward model can estimate more accurate images. However, longer reconstruction time is required. Therefore, to reduce the reconstruction time, three hypotheses are set in this work to develop the medium under different conditions. We compare the reconstructed images using the four forward models to analyze the effects of the various considered medium properties, which include the sound speed, density of the medium, acoustic absorption and dispersion. To reduce the difficulty of hardware manufacturing, a square border ultrasonic transducer array is adopted in the USCT data acquisition system. Penalized leastsquares optimization problems are constructed to obtain numerical solutions of the sound speed and bulk modulus distributions. The reconstruction of the bulk modulus makes the reconstructed sound speed images more accurate. Computer simulations are conducted to compare reconstructed images using the four forward models under different noise conditions. A numerical breast phantom is used to evaluate the performance. The results suggest that for breast imaging, the forward model(which only considers the heterogeneous sound speed) is a compromise option between image accuracy and computational time.

关键词： Sound speed Breast cancer Image reconstruction Ultrasound computed tomography Waveform inversion

Sitting or Standing Data Acquisition Based Breast Ultrasound Computed Tomography

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Chinese Journal of Electronics 2021年第5期30卷 909-917页

作者： li Ruijing CHEN Houjin PENG Yahui li jupeng li Yanfeng School of Electronic and Information Engineering Beijing Jiaotong University

Ultrasound computed tomography(UCT)is a promising approach for early breast cancer ***, current studies which use prone posture to collect breast ultrasonic data cause four problems, a long non-data-acquisition time, inconvenient, possible chances for cross infection, and a large area occupied by *** purpose of this study is to estimate a complete breast UCT image by using sitting or standing data acquisition, which can obtains a more rapid, convenient and sanitary examination process, and a less space occupied by equipment. Therefore, this study proposes a sitting or standing data acquisition based breast UCT method, which is a more practical data acquisition method for breast UCT. This study places a uniform soft sleeve on the outside of the breast so that it would not be deformed significantly due to the change of body posture. Because the soft sleeve is an influencing factor from outside for breast imaging, this study discusses the considerations for selecting that. Computer simulations are conducted to prove the effectiveness of the proposed method. Results suggest that, by using a soft sleeve whose sound speed is between 1450 m/s and 1550 m/s, the proposed method is effective; the biases of the reconstructed images are less than 1% under the 5% noise condition.

关键词： Sonic and ultrasonic radiation (medical uses) Optical, image and video signal processing Sonic and ultrasonic radiation (biomedical imaging/measurement) X-ray techniques: radiography and computed tomography (biomedical imaging/measurement) Sonic and ultrasonic applications Computer vision and image processing techniques X-rays and particle beams (medical uses) Patient diagnostic methods and instrumentation Biology and medical computing Data acquisition Ultrasound computed tomography Image reconstruction Sound speed Breast cancer Full waveform inversion

Ultrasound Computed Tomography of Knee Joint

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Chinese Journal of Electronics 2020年第4期29卷 705-716页

作者： li Ruijing CHEN Houjin PENG Yahui li jupeng li Yanfeng School of Electronic and Information Engineering Beijing Jiaotong University

Ultrasound computed tomography(UCT)is considered to have great potential for the early diagnosis of knee joint *** prior knowledge and sound speeds of tissues, UCT can diagnose a variety of symptoms and the extent of tissue ***, no existing studies can reconstruct the sound speed distributions of knee joints in ***,in this study, sound speed distributions of knee joints are reconstructed to provide an imaging basis for the formulation of a treatment *** addition, Full waveform inversion(FWI) methods are utilized to estimate highresolution ***, for media with large variations in sound speeds, traditional FWI methods may lead to a cycle-skipping phenomenon and incorrect convergence ***, this study proposes a multi-centerfrequency source based FWI method to overcome the above limitations.A penalized least-squares optimization problem is constructed to obtain a numerical solution of the sound speed *** simulations are conducted to prove the effectiveness and robustness of the proposed ***, the reasons for selecting the center frequencies of sources are *** numerical knee joint phantoms are used to evaluate the *** results suggest that the biases of the reconstructed images are less than 1% under a 5% noise condition.

关键词： Sound speed Knee joint Image reconstruction Ultrasound computed tomography Full waveform inversion

新工科背景下突出“三化”内涵的信息工程专业培方案实践

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中国现代教育装备 2024年第7期 7-9,13页

作者：陶丹陈后金李艳凤熊菲李居朋北京交通大学电子信息工程学院北京100044

2019年底,学校启动了2020版本科人才培养方案的修订工作,打造“四通”人才培养模式。以此为契机,针对信息工程专业现行培养方案进行了改革与创新,凝练了信息化、网络化、智能化“三化”的专业内涵,构建了本研贯通、学科融通、产学相通... 详细信息

2019年底,学校启动了2020版本科人才培养方案的修订工作,打造“四通”人才培养模式。以此为契机,针对信息工程专业现行培养方案进行了改革与创新,凝练了信息化、网络化、智能化“三化”的专业内涵,构建了本研贯通、学科融通、产学相通和国际互通的课程体系,可为新工科背景下信息工程专业人才培养提供参考和借鉴。

关键词：信息工程培养方案 “四通”模式课程体系

基于生理特征的乳腺X线图像多视图分析坐标系

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电子与信息学报 2017年第1期39卷 176-182页

作者：曹霖陈后金李居朋程琳北京交通大学电子信息工程学院北京100044 北京大学人民医院乳腺中心北京100044

该文针对乳腺X线图像病变的多视图检测与分析问题,建立了一种基于乳房生理特征的多视图坐标系。通过轴位、中侧斜位视图图像中的乳头、胸肌典型生理特征的提取,以及乳房边缘的椭圆拟合,建立乳腺X线图像多视图分析坐标系,可将乳腺X线图... 详细信息

该文针对乳腺X线图像病变的多视图检测与分析问题,建立了一种基于乳房生理特征的多视图坐标系。通过轴位、中侧斜位视图图像中的乳头、胸肌典型生理特征的提取,以及乳房边缘的椭圆拟合,建立乳腺X线图像多视图分析坐标系,可将乳腺X线图像双侧四视图经非线性映射至同一坐标框架内。以北京大学人民医院乳腺中心提供的图像库为实验数据,从生理特征定位精度、兴趣区域匹配精度等多方面进行坐标系匹配准确度的测试与验证,结果表明该坐标系有助于乳腺X线图像,特别是致密型图像的多视图病变检测。

关键词：乳腺X线图像多视图分析坐标系生理特征区域匹配

对比双侧视图信息的致密型乳腺X线图像肿块检测

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计算机辅助设计与图形学学报 2018年第10期30卷 1917-1924页

作者：曹霖陈后金李居朋李艳凤程琳北京交通大学电子信息工程学院信号与图像处理实验室北京100044 北京大学人民医院乳腺中心北京100044

针对现有双视图肿块检测方法存在的问题,提出一种适用于致密型乳腺X线图像的直接对比双侧视图信息的计算机辅助肿块检测方法.为提高双侧图像对称区域的匹配精度,分割图像中的胸肌区域及腋窝区域,建立仅包含乳房区域的生理坐标系;综合乳... 详细信息

针对现有双视图肿块检测方法存在的问题,提出一种适用于致密型乳腺X线图像的直接对比双侧视图信息的计算机辅助肿块检测方法.为提高双侧图像对称区域的匹配精度,分割图像中的胸肌区域及腋窝区域,建立仅包含乳房区域的生理坐标系;综合乳腺生理特征及肿块病理性质提取感兴趣区域,以梯度图像的局部三元模式特征距离作为尺度测量对称像素的相似度,有效地降低了肿块检测假阳性率.采用北京大学人民医院乳腺中心提供的临床图像进行算法性能实验,结果表明,生理坐标系在定位与匹配对称区域方面具有良好的性能;与现有双视图肿块检测方法相比,在相同的肿块检测正确率下,文中方法获得更低的检测假阳性率.

关键词：致密型乳腺X线图像双视图肿块检测区域匹配相似度测量

计算机辅助检测锥形束CT图像中邻面龋灵敏度的研究

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中华口腔医学杂志 2017年第2期52卷 103-108页

作者：张智玲李居朋李刚马绪臣北京大学口腔医学院·口腔医院口腔医学影像科口腔数字化医疗技术和材料国家工程实验室口腔数字化医学北京市重点实验室 100081 天津市口腔医院口腔医学影像科 300041 北京交通大学电子信息工程学院信号与图像处理实验室 100044

目的建立图像处理与分析系统并以此检测口腔颌面锥形束CT图像中的邻面龋，评价其检测准确性，为邻面龋的早期诊断提供参考。方法建立龋病锥形束CT图像处理与分析系统。由1名评估者和图像处理分析系统分别对北京大学口腔医学院口腔医院4... 详细信息

目的建立图像处理与分析系统并以此检测口腔颌面锥形束CT图像中的邻面龋，评价其检测准确性，为邻面龋的早期诊断提供参考。方法建立龋病锥形束CT图像处理与分析系统。由1名评估者和图像处理分析系统分别对北京大学口腔医学院口腔医院45颗离体牙锥形束cT图像中的邻面龋进行评估，并以组织学检测作为金标准进行受试者工作特征曲线分析、Spearman相关关系检验。结果对锥形束CT图像中邻面龋诊断，评价者肉眼影像诊断与图像处理分析系统诊断的受试者工作特征曲线下面积分别为O．632和0．703，图像处理与分析系统较评价者肉眼影像诊断更准确，二者差异有统计学意义（P=0．023）。图像处理与分析系统对邻面龋深度的评价与金标准的相关关系（相关系数rs=0．525）显著高于观察者肉眼影像诊断（rs=0．457），差异有统计学意义（P=0．000）。结论建立的图像处理与分析系统能提高锥形束CT图像中邻面龋的诊断准确性。

关键词：锥束计算机体层摄影术龋齿诊断计算机辅助软件

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多场景下结构光三维测量激光中心线提取方法

红外与激光工程 2020年第1期49卷 205-212页

作者：宋晓凤李居朋陈后金李丰万成凯北京交通大学电子信息工程学院北京100044 北京世纪瑞尔技术股份有限公司北京100085

结构光三维测量技术是获得物体三维信息的重要途径,激光条纹中心线提取是影响结构光三维测量精度和速度的关键因素。提出了一种适用于多场景下结构光三维测量的激光条纹中心线提取方法,充分利用图像中激光条纹的几何信息和相关性生成自... 详细信息

结构光三维测量技术是获得物体三维信息的重要途径,激光条纹中心线提取是影响结构光三维测量精度和速度的关键因素。提出了一种适用于多场景下结构光三维测量的激光条纹中心线提取方法,充分利用图像中激光条纹的几何信息和相关性生成自适应卷积模板,实现激光条纹图像的滤波和增强处理,使激光条纹横截面灰度值满足高斯分布;经灰度加权法实现激光条纹中心线的亚像素精度定位与提取。实验测试结果表明:该方法可实现多场景下形状、材质各异物体的条纹中心线提取,有效克服了激光条纹亮度分布不均、噪声干扰等影响,单幅图像处理时间缩短为0.107 s且相对误差减少到0.076 5%,有效提高了激光条纹中心线的提取精度和速度。

关键词：三维测量线结构光条纹中心提取自适应卷积灰度加权

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胸部多模MRI图像的结构补偿配准方法

计算机辅助设计与图形学学报 2019年第3期31卷 447-454页

作者：吕文超李艳凤彭亚辉李居朋陈后金北京交通大学电子信息工程学院北京100044

针对胸部多模磁共振(MRI)图像间结构失配问题,提出一种基于结构补偿的配准方法.首先基于相似变换约束进行浮动图像与参考图像的预配准;然后结合图像分割和形态学处理方法对预配准图像进行结构补偿,构造与参考图像组织结构一致的浮动模板... 详细信息

针对胸部多模磁共振(MRI)图像间结构失配问题,提出一种基于结构补偿的配准方法.首先基于相似变换约束进行浮动图像与参考图像的预配准;然后结合图像分割和形态学处理方法对预配准图像进行结构补偿,构造与参考图像组织结构一致的浮动模板;再将浮动模板与参考图像非刚性配准,提取配准变形场;最后将变形场应用于预配准图像,得到配准结果.以失配组织的Jaccard因子作为评价标准,采用模体图像和临床图像对提出的方法进行验证.结果表明在结构失配的胸部多模MRI图像中,本文方法比传统互信息法具有更好的配准性能.

关键词：结构补偿多模配准结构失配磁共振成像