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求解无约束优化问题的两类修正的WYL共轭梯度方法

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应用数学 2019年第2期32卷 415-422页

作者：孙颖异李健孙中波王增辉吉林农业大学信息技术学院吉林长春130118 长春工业大学电气与电子工程学院吉林长春130012 东北师范大学人文学院理工学院吉林长春130117

针对无约束优化问题,通过修正共轭梯度参数,构造新的搜索方向,提出两类修正的WYL共轭梯度法.在每次迭代过程中,两类算法产生的搜索方向均满足充分下降性.在适当条件下,证明了算法的全局收敛性.数值结果表明算法是可行的和有效的.

关键词：共轭梯度法全局收敛无约束优化充分下降方向

改进DenseNet的乳腺癌病理图像八分类研究

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计算机工程与应用 2023年第5期59卷 213-221页

作者：赵晓平王荣发孙中波魏旭全南京信息工程大学计算机与软件学院南京210044 南京信息工程大学数字取证教育部工程研究中心南京210044

目前,在医学图像领域存在乳腺癌组织病理图像自动分类难以应用于临床诊断的现象,究其根源是当前没有大型公开的数据集或数据集数据不均衡。针对上述问题,提出一种结合密集卷积神经网络(dense convolutional network,DenseNet)、注意力机... 详细信息

目前,在医学图像领域存在乳腺癌组织病理图像自动分类难以应用于临床诊断的现象,究其根源是当前没有大型公开的数据集或数据集数据不均衡。针对上述问题,提出一种结合密集卷积神经网络(dense convolutional network,DenseNet)、注意力机制(attention mecheanism)和焦点损失函数(Focal loss)的乳腺癌组织病理图像的多分类模型,即DAFLNet。DAFLNet在乳腺癌组织病理图像数据集BreaKHis上进行训练、验证与测试,最终实验结果显示,该模型对良恶性二分类的识别准确率达到99.1%,对乳腺亚型八分类的识别准确率达到95.5%。证明在数据不均衡的条件下,DAFLNet模型能够准确地对乳腺组织病理图像进行八分类。

关键词：乳腺癌病理图像 DenseNet 八分类注意力机制 Focal loss

A Modified Filter-Trust Region Algorithm and Its Global Convergence Properties for Unconstrained Optimization

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A Modified Filter-Trust Region Algorithm and Its Global Conv...

Bionic covert anti-reverberation active sonar detection method based on imitating whale whistles

第24届中国控制与决策会议

作者： zhongbo sun, Chunling Xu Department of Mathematical Education, College of Humanities and Sciences of Northeast Normal University Shuzhen Jiang College of Humanities and Sciencesof Northeast Normal University

In this paper, we propose a new filter-trust region algorithm for unconstrained optimization problems. A new filter technique is introduced to solve the problem when the direction is not accepted. The theoretical analysis shows that the algorithm is not only global convergence but also R-linearly convergence and even super linearly convergence under some suitable conditions. Numerical results show that this method is effective in minimizing unconstrained optimization problems.

关键词： Filter-trust region method R-linearly convergence Super linearly convergence

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Journal of Measurement Science and Instrumentation 2022年第2期13卷 127-137页

作者： JIANG Jiajia MIAO Yu LI Yao sun zhongbo LI Chunyue WANG Xianquan FU Xiao DUAN Fajie State Key Lab of Precision Measuring Technology and Instruments Tianjin University Tianjin 300072 China System Engineering Research Institute China State Shipbuilding Corporation Beijing 100036 China

The disguised covert detection method that imitates whale calls has received great attention in recent years because it can solve the traditional problem of the trade-off between long-range detection and covert ***,under strong reverberation conditions,traditional echo signal processing methods based on matched filtering will be greatly *** on this,a disguised sonar signal waveform design is proposed based on imitating whale calls and computationally efficient anti-reverberation echo signal processing ***,this article proposed a disguised sonar signal waveform design method based on imitating whale *** method uses linear frequency modulation(LFM)signals to replace LFM-like segments in real whale calls,and extracts the envelope of the real whale call’s LFM-like segment to modify the LFM ***,this article proposed an echo signal processing method of fractional Fourier transform(FrFT)based on target echo locating of synchronization *** method uses the synchronization signal to locate the target echo,and determines the step-size interval of the FrFT based on the information carried by the synchronization *** with the traditional FrFT,this method effectively reduces the amount of calculation and also improves the anti-reverberation ***,the excellent performance of the proposed method is verified by simulation results.

关键词： active sonar system anti-reverberation disguised sonar waveform design echo signal processing

Two-dimensional DOA estimation based on thin array towed by a small autonomous platform

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Journal of Measurement Science and Instrumentation 2021年第3期12卷 258-266页

作者： JIANG Jiajia YANG Guoliang LI Chunyue LI Yao WANG Xianquan sun zhongbo DUAN Fajie FU Xiao State Key Lab of Precision Measuring Technology and Instruments Tianjin University Tianjin 300072 China System Engineering Research Institute China State Shipbuilding Corporation Beijing 100036 China

The small autonomous platform with a thin line array is an important tool for underwater acoustic mobile ***,only one-dimensional(1-D)direction-of-arrival(DOA)of the source signal can be estimated using a thin towed line *** this work,the two-dimensional(2-D)DOA estimation is achieved by the thin line array towed by a small autonomous platform due to its flexible *** perpendicular tow paths are formed through the fast turning of this *** L-shaped array is formed by the same towed array on these two tow paths at different *** the array on these two straight paths,two 1-D DOAs of the source signal are obtained respectively,and then the 2-D DOA based on the formed L-shaped array can be *** effectiveness of proposed approach is verified by numerical simulations and its theoretical error is analyzed.

关键词： towed line array autonomous platform direction-of-arrival(DOA) underwater signal passive sonar

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临近地铁车站爆破振动效应对高层建筑的影响

矿业科学学报 2023年第1期8卷 83-92页

作者：孙中博赵毅鑫王海亮任建东中国矿业大学(北京)共伴生能源精准开采北京市重点实验室北京100083 中国矿业大学(北京)能源与矿业学院北京100083 山东科技大学安全与环境工程学院山东青岛266590

明晰建(构)筑物的爆破振动响应规律在工程和经济上具有重要意义。针对某地铁车站A出入口爆破施工,运用HHT方法分析某小区2号楼振动信号的衰减特征。研究结果表明:沿高程增加方向,三矢量振速峰值先急剧衰减,后在中间楼层呈波浪形变化并... 详细信息

明晰建(构)筑物的爆破振动响应规律在工程和经济上具有重要意义。针对某地铁车站A出入口爆破施工,运用HHT方法分析某小区2号楼振动信号的衰减特征。研究结果表明:沿高程增加方向,三矢量振速峰值先急剧衰减,后在中间楼层呈波浪形变化并在顶层放大,振速变化分为衰减区(0~26.15 m]、波动区(26.15~71.75 m]和放大区(71.75~94.55 m]。随高程增加,Hilbert谱的形态由三峰值逐渐转变为单峰值结构,能量幅值降低;优势频带由75~125 Hz衰减为10~40 Hz,主频向低频过渡,振速放大区楼层振动频率较低且易引发共振。根据地面测点拟合顶层能量谱的构成,验证了顶层放大效应的实质,是对爆破地震波中与建筑物固有频率接近的能量进行选择放大。

关键词：高层建筑爆破振动时频能量 HHT 放大效应

合金元素对T/P91钢焊缝组织及性能的影响

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热加工工艺 2008年第23期37卷 25-26,29页

作者：齐向前田旭海孙忠波闫青亮天津诚信达金属检测技术有限公司天津300384

通过T/P91钢焊条的研制,研究了不同合金元素种类及含量对焊缝组织及性能的影响,结果表明,在其它合金元素含量相近的情况下,钼元素能够明显降低焊缝的相变点,熔敷金属中的钼含量应当按照标准要求的上限选取。

关键词：焊条合金元素相变点熔敷金属

A Sufficient Descent Hybrid Conjugate Gradient Method and Its Global Convergence for Unconstrained Optimization

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A Sufficient Descent Hybrid Conjugate Gradient Method and It...

第24届中国控制与决策会议

作者： zhongbo sun,Department of Mathematical Education, College of Humanities and Sciences of Northeast Normal University Tianxiao Zhu,Haiyin Gao the the Department of Mathematics and Applied Mathematics, Changchun University

In this paper, a modified hybrid conjugate gradient method is proposed for solving unconstrained optimization problems and a new sufficient descent direction is *** theoretical analysis shows that the algorithm is global convergence under some suitable conditions. Numerical results show that this algorithm is effective in unconstrained optimization problems.

关键词： Hybrid conjugate gradient method Sufficient descent direction Unconstrained optimization problem

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河南形象对外传播中文化折扣现象的间性思考

中州大学学报 2023年第3期40卷 51-56页

作者：陈文泰孙仲伯河南大学新闻与传播学院河南开封475001

河南形象是一个自我叙事与他者想象的间性建构产物,也是呈现河南社会发展与生活状态的符号集群。在建构主义视域下,河南形象在对外传播过程中发生了一系列文化折扣现象。本文以文化折扣现象为切口,从世界性的审美意识形态差异、国家性... 详细信息

河南形象是一个自我叙事与他者想象的间性建构产物,也是呈现河南社会发展与生活状态的符号集群。在建构主义视域下,河南形象在对外传播过程中发生了一系列文化折扣现象。本文以文化折扣现象为切口,从世界性的审美意识形态差异、国家性的大河情感及民族认同和区域性的中原语词符号表征三个方面说明河南形象对外传播中文化折扣现象的生成路径。借助韦勒克的文学内部研究与外部研究二分法,在构建多层和深层传播空间、注重文本译介的“使外国化”等方面为减少形象建构中产生的文化折扣影响提供策略之思。

关键词：河南形象对外传播文化折扣间性