期刊文献+
共找到110篇文章
< 1 2 6 >
每页显示 20 50 100
AI辅助肺结节诊断的可视化知识图谱分析
1
作者 李艳红 任俊宇 +1 位作者 孙希文 黄海量 《中国医学计算机成像杂志》 CSCD 北大核心 2023年第5期505-510,共6页
目的:分析人工智能(AI)在辅助肺结节诊断方面的研究现状、热点及问题,以探究我国在该领域的优势与不足,厘清后续发展思路。方法:以Web of Science核心合集数据库作为数据来源,纳入2003年1月至2023年1月AI辅助肺结节诊断相关文献1 468篇... 目的:分析人工智能(AI)在辅助肺结节诊断方面的研究现状、热点及问题,以探究我国在该领域的优势与不足,厘清后续发展思路。方法:以Web of Science核心合集数据库作为数据来源,纳入2003年1月至2023年1月AI辅助肺结节诊断相关文献1 468篇,利用CiteSpace绘制可视化知识图谱,依次分析合作网络、共被引网络和关键词共现。结果:AI辅助肺结节诊断研究存在核心国家、机构;国内已经形成稳定的研究与合作团队,但跨国家的合作明显不足;美国在研究中处于领先、核心地位,中国是后起之秀,韩国是近年的先锋;AI算法导致研究热点的大幅度转移,目前研究重点是利用CT断层扫描和深度学习算法辅助判断肺结节和低密度磨玻璃结节,进行诊断和病因分析。结论:AI辅助肺结节诊断的研究近年飞速发展,需增强各国研究团队的合作。此领域受算法性能影响较大,后继应该继续关注AI等用于计算机辅助诊断的新算法性能的提升。 展开更多
关键词 肺结节 AI CiteSpace 文献计量学 知识图谱
下载PDF
Machine Learning With Data Assimilation and Uncertainty Quantification for Dynamical Systems:A Review 被引量:2
2
作者 Sibo Cheng César Quilodrán-Casas +14 位作者 Said Ouala Alban Farchi Che Liu Pierre Tandeo Ronan Fablet Didier Lucor Bertrand Iooss Julien Brajard Dunhui Xiao Tijana Janjic Weiping Ding Yike Guo Alberto Carrassi Marc Bocquet Rossella Arcucci 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2023年第6期1361-1387,共27页
Data assimilation(DA)and uncertainty quantification(UQ)are extensively used in analysing and reducing error propagation in high-dimensional spatial-temporal dynamics.Typical applications span from computational fluid ... Data assimilation(DA)and uncertainty quantification(UQ)are extensively used in analysing and reducing error propagation in high-dimensional spatial-temporal dynamics.Typical applications span from computational fluid dynamics(CFD)to geoscience and climate systems.Recently,much effort has been given in combining DA,UQ and machine learning(ML)techniques.These research efforts seek to address some critical challenges in high-dimensional dynamical systems,including but not limited to dynamical system identification,reduced order surrogate modelling,error covariance specification and model error correction.A large number of developed techniques and methodologies exhibit a broad applicability across numerous domains,resulting in the necessity for a comprehensive guide.This paper provides the first overview of state-of-the-art researches in this interdisciplinary field,covering a wide range of applications.This review is aimed at ML scientists who attempt to apply DA and UQ techniques to improve the accuracy and the interpretability of their models,but also at DA and UQ experts who intend to integrate cutting-edge ML approaches to their systems.Therefore,this article has a special focus on how ML methods can overcome the existing limits of DA and UQ,and vice versa.Some exciting perspectives of this rapidly developing research field are also discussed.Index Terms-Data assimilation(DA),deep learning,machine learning(ML),reduced-order-modelling,uncertainty quantification(UQ). 展开更多
关键词 ASSIMILATION OVERCOME apply
下载PDF
Structural Connectivity Enhanced Anisotropic 3D Network for Brain Midline Delineation
3
作者 Yufan Liu Kongming Liang +6 位作者 Yinuo Jing Shen Wang Zhanyu Ma Yiming Li Yizhou Yu Yizhou Wang Jun Guo 《Journal of Beijing Institute of Technology》 EI CAS 2023年第5期562-578,共17页
Brain midline delineation can facilitate the clinical evaluation of brain midline shift,which has a pivotal role in the diagnosis and prognosis of various brain pathology.However,there are still challenges for brain m... Brain midline delineation can facilitate the clinical evaluation of brain midline shift,which has a pivotal role in the diagnosis and prognosis of various brain pathology.However,there are still challenges for brain midline delineation:1)the largely deformed midline is hard to localize if mixed with severe cerebral hemorrhage;2)the predicted midlines of recent methods are not smooth and continuous which violates the structural priority.To overcome these challenges,we propose an anisotropic three dimensional(3D)network with context-aware refinement(A3D-CAR)for brain midline modeling.The proposed network fuses 3D context from different two dimensional(2D)slices through asymmetric context fusion.To exploit the elongated structure of the midline,an anisotropic block is designed to balance the difference between the adjacent pixels in the horizontal and vertical directions.For maintaining the structural priority of a brain midline,we present a novel 3D connectivity regular loss(3D CRL)to penalize the disconnectivity between nearby coordinates.Extensive experiments on the CQ dataset and one in-house dataset show that the proposed method outperforms three state-of-the-art methods on four evaluation metrics without excessive computational burden. 展开更多
关键词 brain midline delineation refinement network structure prior connectivity regular loss
下载PDF
基于YOLOv5s和超声图像的儿童肠套叠特征检测模型 被引量:1
4
作者 陈星 俞凯 +2 位作者 袁贞明 黄坚 李哲明 《杭州师范大学学报(自然科学版)》 CAS 2024年第1期10-19,共10页
为帮助医生快速寻找到儿童腹部超声中肠套叠的病变特征并实现肠套叠超声诊后数据的快速质检,文章将目标检测算法应用于儿童腹部超声图像检测肠套叠“同心圆”征.首先探索了基于YOLOv5s的儿童肠套叠检测模型,发现该模型检测肠套叠“同心... 为帮助医生快速寻找到儿童腹部超声中肠套叠的病变特征并实现肠套叠超声诊后数据的快速质检,文章将目标检测算法应用于儿童腹部超声图像检测肠套叠“同心圆”征.首先探索了基于YOLOv5s的儿童肠套叠检测模型,发现该模型检测肠套叠“同心圆”征的精确度、召回率、F 1分数、mAP@0.5、FPS以及参数量等方面均优于Faster RCNN.进一步,为解决肉眼难以观察的“同心圆”征的检测问题,使用双向特征金字塔网络,并将注意力机制加入YOLOv5s网络,形成基于YOLOv5s_BiFPN_SE框架的儿童肠套叠“同心圆”征检测模型.该模型检测的精确率、召回率、F 1分数、mAP@0.5分别达到了91.33%、90.73%、91.03%、88.77%,性能更优于YOLOv5s. 展开更多
关键词 目标检测 肠套叠 超声图像 “同心圆”征 双向特征金字塔网络 注意力机制
下载PDF
基于CT图像结合放射组学和语义特征的机器学习模型诊断非结核分枝杆菌肺病和肺结核的研究
5
作者 仲玲珊 王莉 +6 位作者 张硕 李楠 杨晴媛 丁文龙 陈星枝 黄陈翠 邢志珩 《中国防痨杂志》 CAS CSCD 北大核心 2024年第9期1042-1049,共8页
目的:探索基于胸部CT图像的结合放射组学特征和语义特征的机器学习模型,以准确诊断非结核分枝杆菌肺病和肺结核。方法:回顾性收集天津市海河医院2017年1月至2020年12月确诊的120例非结核分枝杆菌肺病和120例肺结核患者的胸部CT图像,分... 目的:探索基于胸部CT图像的结合放射组学特征和语义特征的机器学习模型,以准确诊断非结核分枝杆菌肺病和肺结核。方法:回顾性收集天津市海河医院2017年1月至2020年12月确诊的120例非结核分枝杆菌肺病和120例肺结核患者的胸部CT图像,分层随机抽取168例(70%)作为训练集,72例(30%)作为测试集。收集西安市胸科医院确诊的25例非结核分枝杆菌肺病和25例肺结核患者的胸部CT图像,作为外部验证集。从全部胸部CT图像中提取12种语义特征和2107个放射组学特征,其中放射组学特征通过特征降维保留40个。采用支持向量机(support vector machines,SVM)算法建立了三个机器学习分类模型,分别是语义模型、放射组学模型、结合放射组学和语义特征的放射组学-语义模型。通过受试者工作特征曲线及曲线下面积对机器学习模型的诊断性能进行评估,用DeLong检验比较三种模型之间差异的统计学意义。结果:在测试集上,放射组学-语义模型、放射组学模型和语义模型的曲线下面积分别为0.9853、0.9282、0.7901。语义模型和放射组学-语义模型,语义模型和放射组学模型之间差异均有统计学意义(Z=2.759,P=0.006;Z=2.230,P=0.026);放射组学-语义模型和放射组学模型之间差异无统计学意义(Z=0.761,P=0.502)。在外部验证集上,放射组学-语义模型、放射组学模型和语义模型的曲线下面积分别为0.9216、0.9024和0.7624。放射组学-语义模型和语义模型之间差异有统计学意义(Z=2.126,P=0.034);放射组学-语义模型和放射组学模型之间差异无统计学意义(Z=0.368,P=0.713)。结论:与语义模型相比,结合放射组学和语义特征的机器学习模型在区分肺结核和非结核分枝杆菌肺病方面具有良好的诊断效率和临床应用价值,尽管与放射组学模型相比,其性能改进并不显著。 展开更多
关键词 结核 分枝杆菌感染 诊断 鉴别 体层摄影术 X线计算机 影像组学
下载PDF
神经机器阅读模型综述
6
作者 骆丹 张鹏 +2 位作者 马路 王斌 王丽宏 《信息安全学报》 CSCD 2024年第2期122-139,共18页
近年来,随着互联网的高速发展,网络内容安全问题日益突出,是网络治理的核心任务之一。文本内容是网络内容安全最为关键的研究对象,然而自然语言本身固有的模糊性和灵活性给网络舆情监控和网络内容治理带来了很大的困难。因此,如何准确... 近年来,随着互联网的高速发展,网络内容安全问题日益突出,是网络治理的核心任务之一。文本内容是网络内容安全最为关键的研究对象,然而自然语言本身固有的模糊性和灵活性给网络舆情监控和网络内容治理带来了很大的困难。因此,如何准确地理解文本内容,是网络内容治理的关键问题。目前,文本内容理解的核心支撑技术是基于自然语言处理的方法。机器阅读理解作为自然语言处理领域中的一项综合性任务,可以深层次地分析、全面地理解网络内容,在网络舆论监测和网络内容治理上发挥着重要作用。近年来,深度学习技术已在图像识别、文本分类、自然语言处理等多个领域中取得显著成果,基于深度学习的机器阅读理解方法也被广泛研究。特别是近年来各种大规模数据集的公开,加快了神经机器阅读理解的发展,各种结合不同神经网络的机器阅读模型被相继提出。本文旨在对神经机器阅读模型进行综述。首先介绍机器阅读理解的发展历史和研究现状;然后阐述机器阅读理解的任务定义,并列举出有代表性的数据集以及神经机器阅读模型;再介绍四种新趋势目前的研究进展;最后提出神经机器阅读模型当前存在的问题,并且分析机器阅读理解如何应用于网络内容治理问题以及对未来的发展趋势进行展望。 展开更多
关键词 网络内容安全 网络舆情监测 机器阅读理解 自然语言处理 深度学习 神经网络
下载PDF
基于T2WI的ResNet深度学习模型术前预测膀胱癌病理分级的研究
7
作者 黄翔 曹康养 +6 位作者 邹玉坚 邓磊 张蔚菁 杨水清 张坤林 朱玉容 李建鹏 《磁共振成像》 CAS CSCD 北大核心 2024年第1期125-131,共7页
目的 本研究旨在构建并验证基于T2加权成像(T2-weighted imaging, T2WI)的50层深度残差网络(50-layer deep residualnetwork,ResNet-50)深度学习(deeplearning,DL)模型术前预测膀胱癌(bladder cancer, BCa)病理分级的效能。材料与方法 ... 目的 本研究旨在构建并验证基于T2加权成像(T2-weighted imaging, T2WI)的50层深度残差网络(50-layer deep residualnetwork,ResNet-50)深度学习(deeplearning,DL)模型术前预测膀胱癌(bladder cancer, BCa)病理分级的效能。材料与方法 回顾性分析来自南方医科大学第十附属医院(中心1)和中山大学肿瘤防治中心(中心2)共169名BCa患者的211个肿瘤病灶数据。以病理组织学诊断作为金标准,以肿瘤病灶为单位进行分析,其中高级别尿路上皮癌(high grade urothelial carcinoma, HGUC)为111个,低级别尿路上皮癌(low grade urothelial carcinoma, LGUC)为100个。采用DL模型的ResNet-50方法,基于中心1内部训练集构建模型,所得出的模型在中心1的内部测试集中测试后筛选出最优模型,随后在中心2的外部测试集上进行独立验证。采用受试者工作特征(receiver operating characteristic, ROC)曲线下面积(area under the curve, AUC)、准确率、敏感度和特异度对模型性能进行评估,并进行特征可视化展示。结果 DL模型在内部测试集的AUC为0.856(95%CI:0.723~0.941),准确率为80.9%(95%CI:69.6%~92.1%),敏感度为77.8%(95%CI:65.9%~89.7%),特异度为82.8%(95%CI:72.0%~93.6%);在外部测试集的AUC为0.814 (95%CI:0.686~0.906),准确率为78.2%(95%CI:67.3%~89.1%),敏感度为77.3%(95%CI:66.2%~88.3%),特异度为81.8%(95%CI:71.6%~92.0%)。特征可视化结果显示DL模型较高激活区域与BCa病灶基本重叠,可正确识别BCa靶区域,同时对HGUC与LGUC的特征有一定区分度。结论 本研究首次采用DL方法在术前建立基于T2WI的BCa病理分级预测模型,并在双中心进行验证。该模型无创、客观,泛化性及可重复性强,具有较高的预测准确性,有助于临床术前更精准地诊断。 展开更多
关键词 膀胱癌 深度学习 磁共振成像 肿瘤分级
下载PDF
面向中文微博的情绪-原因对抽取数据集构建及分析研究
8
作者 陈仲豪 朱军楠 +2 位作者 周玉 向露 宗成庆 《中文信息学报》 CSCD 北大核心 2024年第10期135-143,共9页
情绪-原因对抽取(ECPE)任务旨在从给定文档中同步抽取情绪子句及其对应的原因子句,该任务在新闻领域得到了广泛研究。然而,社交媒体领域ECPE任务的研究相对较少,主要原因在于缺少适用的数据集。与新闻领域相比,该领域更具挑战性和实用性... 情绪-原因对抽取(ECPE)任务旨在从给定文档中同步抽取情绪子句及其对应的原因子句,该任务在新闻领域得到了广泛研究。然而,社交媒体领域ECPE任务的研究相对较少,主要原因在于缺少适用的数据集。与新闻领域相比,该领域更具挑战性和实用性:(1)在社交媒体领域,情绪表达更加多样化、非规范化;(2)以往的研究忽略了情绪造成的主观意图,其对于决策分析有很重要的价值。针对以上问题,该文首先构建了一个面向中文微博的情绪原因抽取数据集,并对其中5009条数据进行了人工标注。该数据集具备以下特点:(1)收录了隐喻、反讽等形式的情绪表达,标注了细粒度的情绪类别;(2)定义了三种类型的意图,并标注了意图子句;(3)当前规模最大的中文情绪-原因对抽取数据集。结合数据集特点,该文提出一种融合情绪类别和意图信息的情绪-原因对抽取方法,并将该方法与多个ECPE主流方法进行了比较分析。实验结果表明,该文方法可以更有效提升社交媒体领域情绪-原因对抽取的效果。 展开更多
关键词 情绪-原因对抽取 中文社交媒体 微博数据集
下载PDF
一种约束制导的机器学习框架漏洞检测方法
9
作者 刘昭 邹权臣 +4 位作者 于恬 王旋 张德岳 孟国柱 陈恺 《计算机学报》 EI CAS CSCD 北大核心 2024年第5期1120-1137,共18页
随着机器学习在社会各领域中自主决策场景的广泛应用,人们对机器学习框架中潜在漏洞的担忧也在日益增加.然而,由于其复杂的实现,针对框架的系统化、自动化测试成为一项艰巨的任务.现有对机器学习框架测试的研究在生成有效测试数据方面... 随着机器学习在社会各领域中自主决策场景的广泛应用,人们对机器学习框架中潜在漏洞的担忧也在日益增加.然而,由于其复杂的实现,针对框架的系统化、自动化测试成为一项艰巨的任务.现有对机器学习框架测试的研究在生成有效测试数据方面尚不成熟,导致测试数据无法通过合法性校验并因此无法检测到目标漏洞.本文提出了ConFL,一种基于约束的机器学习框架模糊测试工具.ConFL能够自动从框架源代码中提取约束而无需任何先验知识.在约束的指导下,ConFL可以生成能够通过校验的有效输入,并执行到框架更深层次的代码逻辑.此外,本文设计了一种算子分组调度技术来提高模糊测试的效率.为了证明ConFL的有效性,本文主要在Tensor-Flow框架上评估了其性能.测试发现,与现有的SOTA工具相比,ConFL能够覆盖更多的代码行,并生成更多有效的测试数据;在相同版本的TensorFlow框架上,ConFL能检测出更多的已知漏洞.此外,ConFL在不同版本的TensorFlow中发现了84个未知漏洞,这些漏洞全部被官方修复并被分配了CVE编号,其中包括3个严重漏洞,13个高危漏洞.最后,本文还在PyTorch和PaddlePaddle中进行了通用性测试,迄今为止发现了7个漏洞. 展开更多
关键词 机器学习框架 约束提取 算子测试 模糊测试 漏洞检测
下载PDF
Image super‐resolution via dynamic network 被引量:1
10
作者 Chunwei Tian Xuanyu Zhang +2 位作者 Qi Zhang Mingming Yang Zhaojie Ju 《CAAI Transactions on Intelligence Technology》 SCIE EI 2024年第4期837-849,共13页
Convolutional neural networks depend on deep network architectures to extract accurate information for image super‐resolution.However,obtained information of these con-volutional neural networks cannot completely exp... Convolutional neural networks depend on deep network architectures to extract accurate information for image super‐resolution.However,obtained information of these con-volutional neural networks cannot completely express predicted high‐quality images for complex scenes.A dynamic network for image super‐resolution(DSRNet)is presented,which contains a residual enhancement block,wide enhancement block,feature refine-ment block and construction block.The residual enhancement block is composed of a residual enhanced architecture to facilitate hierarchical features for image super‐resolution.To enhance robustness of obtained super‐resolution model for complex scenes,a wide enhancement block achieves a dynamic architecture to learn more robust information to enhance applicability of an obtained super‐resolution model for varying scenes.To prevent interference of components in a wide enhancement block,a refine-ment block utilises a stacked architecture to accurately learn obtained features.Also,a residual learning operation is embedded in the refinement block to prevent long‐term dependency problem.Finally,a construction block is responsible for reconstructing high‐quality images.Designed heterogeneous architecture can not only facilitate richer structural information,but also be lightweight,which is suitable for mobile digital devices.Experimental results show that our method is more competitive in terms of performance,recovering time of image super‐resolution and complexity.The code of DSRNet can be obtained at https://github.com/hellloxiaotian/DSRNet. 展开更多
关键词 CNN dynamic network image super‐resolution lightweight network
下载PDF
Two-dimensional Parameter Relationships for W UMa-type Systems Revisited 被引量:2
11
作者 Atila Poro Ehsan Paki +6 位作者 Ailar Alizadehsabegh Mehdi Khodadadilori Selda Ranjbar Salehian Mahya Hedayatjoo Fatemeh Hashemi Yasaman Dashti Fatemeh Mohammadizadeh 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2024年第1期51-58,共8页
Reviewing the empirical and theoretical parameter relationships between various parameters is a good way to understand more about contact binary systems.In this investigation,two-dimensional(2D)relationships for P–MV... Reviewing the empirical and theoretical parameter relationships between various parameters is a good way to understand more about contact binary systems.In this investigation,two-dimensional(2D)relationships for P–MV(system),P–L1,2,M1,2–L1,2,and q–Lratiowere revisited.The sample used is related to 118 contact binary systems with an orbital period shorter than 0.6 days whose absolute parameters were estimated based on the Gaia Data Release 3 parallax.We reviewed previous studies on 2D relationships and updated six parameter relationships.Therefore,Markov chain Monte Carlo and Machine Learning methods were used,and the outcomes were compared.We selected 22 contact binary systems from eight previous studies for comparison,which had light curve solutions using spectroscopic data.The results show that the systems are in good agreement with the results of this study. 展开更多
关键词 (stars:)binaries(including multiple):close stars:fundamental parameters methods:data analysis
下载PDF
First Light Curve Analysis of NSVS 8294044,V1023 Her,and V1397 Her Contact Binary Systems 被引量:1
12
作者 Atila Poro Sabrina Baudart +7 位作者 Mahshid Nourmohammad Zahra Sabaghpour Arani Fatemeh Farhadi Selda Ranjbar Salehian Ahmad Sarostad Saeideh Ranjbaryan Iri Olya Maryam Hadizadeh AmirHossein Khodaei 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2024年第5期1-12,共12页
The first photometric light curve investigation of the NSVS 8294044,V1023 Her,and V1397 Her binary systems is presented.We used ground-based observations for the NSVS 8294044 system and Transiting Exoplanet Survey Sat... The first photometric light curve investigation of the NSVS 8294044,V1023 Her,and V1397 Her binary systems is presented.We used ground-based observations for the NSVS 8294044 system and Transiting Exoplanet Survey Satellite data for V1023 Her and V1397 Her.The primary and secondary times of minima were extracted from al the data,and,by collecting the literature,a new ephemeris was computed for each system.Linear fits for the O-C diagrams were conducted using the Markov Chain Monte Carlo (MCMC) method.Light curve solutions were performed using the PHysics Of Eclipsing BinariEs Python code and the MCMC approach.The systems were found to be contact binary stars based on the fillout factor and mass ratio.V1023 Her showed the O’Connell effect and a cold starspot on the secondary component was required for the light curve solution.The absolute parameters of the system were estimated based on an empirical relationship between orbital period and mass.We presented a new T–M equation based on a sample of 428 contact binary systems and found that our three target systems were in good agreement with the fit.The positions of the systems were also depicted on the M–L,M–R,q–L_(ratio),and M_(tot)–J_(0)diagrams in the logarithmic scales. 展开更多
关键词 (stars:)binaries eclipsing-techniques photometric-stars individual(NSVS 8294044)
下载PDF
BSN:The First Light Curve Analysis of the Total Eclipse Binary System EL Tuc
13
作者 Elham Sarvari Eduardo Fernández Lajús Atila Poro 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2024年第10期66-75,共10页
We conducted the first light curve study of the binary star EL Tuc within the Binary Systems of South and North project's framework.The photometric observations were made using standard multiband BVR_cI_c filters ... We conducted the first light curve study of the binary star EL Tuc within the Binary Systems of South and North project's framework.The photometric observations were made using standard multiband BVR_cI_c filters at an observatory in Argentina.We presented a new ephemeris for EL Tuc and a linear fit to the O–C diagram,utilizing our extracted times of minima and additional literature.We employed the PHysics Of Eclipsing BinariEs Python code and the Markov chain Monte Carlo approach for the system's light curve analysis.The target system's light curve solution required a cold starspot on the hotter component.We conclude that EL Tuc is a total contact binary system with a low mass ratio of q=0.172±0.002,an orbital inclination of i=83°.74±0°.40,and a fillout factor of f=53.7%±1.6%.We used the P-a relationship and the Gaia Data Release 3 parallax method to determine the absolute parameters of EL Tuc to compare the precision of our results.This system was classified as W-type based on the mass and effective temperature of the companion stars.The positions of the systems were depicted on the M-L,M-R,T-M,and q-Lratiodiagrams.The relationship between the spectroscopic and photometric mass ratios of binaries was discussed. 展开更多
关键词 (stars:)binaries:eclipsing stars:individual(EL Tuc) line:identification
下载PDF
Assessment and Visualization of Ki67 Heterogeneity in Breast Cancers through Digital Image Analysis
14
作者 Chien-Hui Wu Min-Hsiang Chang +1 位作者 Hsin-Hsiu Tsai Yi-Ting Peng 《Advances in Breast Cancer Research》 CAS 2024年第2期11-26,共16页
The Ki67 index (KI) is a standard clinical marker for tumor proliferation;however, its application is hindered by intratumoral heterogeneity. In this study, we used digital image analysis to comprehensively analyze Ki... The Ki67 index (KI) is a standard clinical marker for tumor proliferation;however, its application is hindered by intratumoral heterogeneity. In this study, we used digital image analysis to comprehensively analyze Ki67 heterogeneity and distribution patterns in breast carcinoma. Using Smart Pathology software, we digitized and analyzed 42 excised breast carcinoma Ki67 slides. Boxplots, histograms, and heat maps were generated to illustrate the KI distribution. We found that 30% of cases (13/42) exhibited discrepancies between global and hotspot KI when using a 14% KI threshold for classification. Patients with higher global or hotspot KI values displayed greater heterogenicity. Ki67 distribution patterns were categorized as randomly distributed (52%, 22/42), peripheral (43%, 18/42), and centered (5%, 2/42). Our sampling simulator indicated analyzing more than 10 high-power fields was typically required to accurately estimate global KI, with sampling size being correlated with heterogeneity. In conclusion, using digital image analysis in whole-slide images allows for comprehensive Ki67 profile assessment, shedding light on heterogeneity and distribution patterns. This spatial information can facilitate KI surveys of breast cancer and other malignancies. 展开更多
关键词 Ki67 Heterogeneity Breast Cancer Digital Image Analysis
下载PDF
BSN:Photometric Light Curve Analysis of Two Contact Binary Systems LS Del and V997 Cyg
15
作者 Atila Poro Mehmet Tanriver +9 位作者 Elham Sarvari Shayan Zavvarei Hossein Azarara Laurent Corp Sabrina Baudart Asma Ababafi Nazanin Kahali Poor Fariba Zare Ahmet Bulut Ahmet Keskin 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2024年第4期192-213,共22页
The light curve analyses and orbital period variations for two contact binary stars,LS Del and V997 Cyg,are presented in this work which was conducted in the frame of the Binary Systems of South and North project Grou... The light curve analyses and orbital period variations for two contact binary stars,LS Del and V997 Cyg,are presented in this work which was conducted in the frame of the Binary Systems of South and North project Ground-based photometric observations were performed at two observatories in France.We used the Transiting Exoplanet Survey Satellite(TESS)data for extracting times of minima and light curve analysis of the targe systems.The O-C diagram for both systems displays a parabolic trend.LS Del and V997 Cyg’s orbital periods are increasing at rates of dP/dt=7.20×10^(-08)days yr^(-1)and dP/dt=2.54×10^(-08)days yr^(-1),respectively Therefore,it can be concluded that mass is being transferred from the less massive star to the more massive component with a rate of dM/dt=-1.96×10^(-7)M_(⊙)yr^(-1)for the LS Del system,and dM/dt=-3.83×10^(-7)M_(⊙)yr-1for V997 Cyg.The parameters of a third possible object in the system are also considered.The PHysics Of Eclipsing BinariEs Python code was used to analyze the light curves.The light curve solutions needed a cold starspot due to the asymmetry in the LS Del system’s light curve maxima.The mass ratio fill-out factor,and star temperature all indicate that both systems are contact binary types in this investigation.Two methods were applied to estimate the absolute parameters of the systems:one method relied on the parallax of Gaia DR3,and the other used a P-M relationship.The positions of the systems are also depicted on the M-L,M-R q-L_(ratio),and logM_(tot)-logJ_(0)diagrams.We recommend that further observations and investigations be done on the existence of a fourth body in this system. 展开更多
关键词 (stars:)binaries:eclipsing methods:observational stars:individual(LS Del and V997 Cyg)
下载PDF
BLOCKCHAIN TECHNOLOGIES AND APPLICATIONS 被引量:1
16
作者 Erwu Liu Alex“Sandy”Pentland +5 位作者 Greg Adamson Ramesh Ramadoss Yixian Yang Wei-Tek Tsai Yunlei Zhao Min Lei 《China Communications》 SCIE CSCD 2019年第6期I0004-I0006,共3页
Blockchain is a technology that uses community validation to synchronize the content of ledgers replicated by multiple users.Although Blockchain derives its origins from technologies introduced decades ago,recently it... Blockchain is a technology that uses community validation to synchronize the content of ledgers replicated by multiple users.Although Blockchain derives its origins from technologies introduced decades ago,recently it has received an astonishing amount of attention in both academic and industry due to its charac-teristics of decentralization,point-to-point transmission,transparency,traceability,non-tampering,and data security.Both researchers and practitioners have recognized that Blockchain can be used to solve complex technical or socio-economic problems. 展开更多
关键词 Blockchain ledgers replicated MULTIPLE USERS
下载PDF
Global Motion Estimation in Frequency Domain
17
作者 王栋 Wang +4 位作者 Zhigang Wang Wei Xu Xiaoming 《High Technology Letters》 EI CAS 2001年第4期42-45,共4页
Because some efficient motion estimation algorithms need considering global camera motion such as zooming, panning, rotating and tilting, a frequency domain algorithm is proposed to solve this problem. Utilizing the m... Because some efficient motion estimation algorithms need considering global camera motion such as zooming, panning, rotating and tilting, a frequency domain algorithm is proposed to solve this problem. Utilizing the magnitude relationship and phase relationship between successive images’ spectra, the authors can solve the full parameter camera motion robustly with acceptable computational complexity. 展开更多
关键词 DOMAIN
下载PDF
从空间认知到虚拟再现:数字化党史地图的实践探索
18
作者 李煜 冯昊 +2 位作者 徐跃家 刘平浩 陈奕彤 《华中建筑》 2023年第5期1-5,共5页
数字时代,如何借助新兴技术完成地理图示绘制以满足人类社会不断涌现的空间认知需求已经成为建成环境领域的重要命题。《数字化党史地图》项目基于地图与空间认知理论,从内容选题、数据搜集、模型制作、呈现表达四个方面进行创新性探索... 数字时代,如何借助新兴技术完成地理图示绘制以满足人类社会不断涌现的空间认知需求已经成为建成环境领域的重要命题。《数字化党史地图》项目基于地图与空间认知理论,从内容选题、数据搜集、模型制作、呈现表达四个方面进行创新性探索;以城市红色空间为主题,基于三维扫描、数字孪生、虚拟现实等技术构建了面向数字时代人本尺度城市空间认知需求的地理图示实践框架,为城市空间认知研究提供了新的思路。 展开更多
关键词 数字技术 空间认知 地图 红色空间
下载PDF
面向中文医学文本的知识图谱通用评测系统设计 被引量:1
19
作者 林晓兰 梁铭标 +8 位作者 王浩 张志辉 江之晗 麻硕 钱鹏 谷祥拓 陈秀娟 黄帅 梁会营 《医疗卫生装备》 CAS 2023年第1期13-18,共6页
目的:设计一种面向中文医学文本的知识图谱通用评测系统,以为医学研究人员、医疗机构及企业评估知识图谱技术水平提供手段。方法:该系统以医学专家人工标注的标准评测数据集为基础,以深度学习算法模型为支撑,采用浏览器/服务器(Browser/... 目的:设计一种面向中文医学文本的知识图谱通用评测系统,以为医学研究人员、医疗机构及企业评估知识图谱技术水平提供手段。方法:该系统以医学专家人工标注的标准评测数据集为基础,以深度学习算法模型为支撑,采用浏览器/服务器(Browser/Server,B/S)架构设计,采用Python 3.7编程,由评测任务以及数据集配置与管理、知识图谱任务评测、评测指标记录与对比3个功能模块组成。结果:采用该系统可以根据知识图谱评测需求自定义评测项目,灵活配置必选和可选的评测内容,且在评测后可以提供单方面或者综合能力的量化成绩。结论:该系统解决了医学知识图谱领域面临的无法评估技术性能水平的痛点,为医学领域的知识图谱评测提供了参考。 展开更多
关键词 医学文本 知识图谱 知识图谱评测 深度学习
下载PDF
预测ER弱阳性乳腺癌状态的机器学习模型的建立及验证
20
作者 徐梓航 牛淑瑶 +5 位作者 沈荣波 贾占莉 商久妍 王新乐 张硕 刘月平 《临床与实验病理学杂志》 CAS 北大核心 2023年第7期782-787,共6页
目的探讨利用机器学习算法预测ER弱阳性乳腺癌的状态。方法收集710例原发性浸润性乳腺癌,其中139例ER阴性(<1%)和311例ER阳性(>10%)乳腺癌作为训练队列,260例ER弱阳性(1%~10%)乳腺癌作为测试队列。深度学习分割模型(LinkNet)用于... 目的探讨利用机器学习算法预测ER弱阳性乳腺癌的状态。方法收集710例原发性浸润性乳腺癌,其中139例ER阴性(<1%)和311例ER阳性(>10%)乳腺癌作为训练队列,260例ER弱阳性(1%~10%)乳腺癌作为测试队列。深度学习分割模型(LinkNet)用于分割并提取肿瘤细胞的形态特征。基于朴素贝叶斯机器学习算法,利用从训练队列中提取的12个临床病理特征和14个形态特征开发机器学习预测模型,并进行内部验证。利用ROC曲线的曲线下面积(AUC)反映预测模型的性能。利用预测模型对测试队列进行ER状态预测。对比分析两组的临床病理特征、ESR1 mRNA的表达水平和预后。结果ER阴性与ER阳性乳腺癌在组织学类型(P=0.01)、淋巴结转移(P=0.02)、组织学分级(P<0.001)、PR(P<0.001)、HER2(P<0.001)和Ki-67(P<0.001)表达差异有显著性。基于朴素贝叶斯机器学习算法构建预测模型,5倍交叉验证显示,在训练队列中预测模型对ER状态的预测性能优异(AUC=0.91±0.03)。ER状态预测结果显示,260例ER弱阳性乳腺癌中206例(79.23%)被划分为阴性组,54例(20.77%)被划分为阳性组。与ER阳性组相比,ER阴性组组织学分级更高、Ki-67高表达、ESR1 mRNA表达水平低,内分泌治疗获益更少,患者预后更差。结论机器学习模型能够较为精准地对乳腺癌ER表达状态进行预测,为进一步明确ER弱阳性乳腺癌的状态提供了新视角,协助临床医师做出更为精准的治疗决策。 展开更多
关键词 乳腺肿瘤 ER弱阳性 机器学习 朴素贝叶斯
下载PDF
上一页 1 2 6 下一页 到第
使用帮助 返回顶部