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二阶各向异性高斯导数滤波器的斑点检测算法

光电子技术 2024年第1期44卷 72-77页

作者：于文雅任劼章为川鲁磊西安工程大学电子信息学院西安710048 西安交通大学信息与通信工程学院西安710049

针对目前斑点检测算法对斑点进行定位和描述斑点形状的能力不足等问题,提出了一种基于多尺度二阶各向异性高斯方向导数滤波器的斑点检测算法。二阶各向异性高斯方向导数(SOAGDD)可以很好的提取不同方向的图像信息,并且可以很好的应对噪... 详细信息

针对目前斑点检测算法对斑点进行定位和描述斑点形状的能力不足等问题,提出了一种基于多尺度二阶各向异性高斯方向导数滤波器的斑点检测算法。二阶各向异性高斯方向导数(SOAGDD)可以很好的提取不同方向的图像信息,并且可以很好的应对噪声干扰,采用多尺度二阶各向异性高斯方向导数滤波器对输入图像进行平滑处理,对处理后图像进行区域极值计算。实验证明提出的方法在兴趣点检测的定位、检测到的兴趣点的形状描述和图像匹配方面具有优越性。

关键词：二阶各向异性高斯方向导数滤波器斑点检测多尺度兴趣点检测

Microstructure and Mechanical Properties of an Extruded Mg-2Dy-0.5Zn Alloy

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Journal of Materials Science & Technology 2012年第6期28卷 543-551页

作者： Cuangli Bi Daqing Fang weichuan zhang Jothi Sudagar Qingxin zhang JiansheLian Zhonghao diang Key Lab of Automobile Materials Ministry of EducationCollege of Materials Science and EngineeringJilin UniversityNanling CampusChangchun 130025China College of Materials Science and Engineering Taiyuan University of Science and TechnologyTaiyuan 030024China

Microstructure and mechanical properties of an extruded Mg-2Dy-0.5Zn （at.%） alloy during isothermal ageing at 180℃ were investigated. Microstructure of the as-extruded alloy is mainly composed of α-Mg phase, 14H long period stacking order （LPSO） phase and small amounts of （Mg, Zn）=Dy particle phases. During ageing, the 14H LPSO phase forms and develops and its volume fraction increases with increasing ageing time. Tensile test showed that the peak-aged alloy exhibits similar yield and ultimate tensile strengths and elongation to failure at room temperature, 100℃ and 200℃, but excellent elevated temperature strengths at 300℃ as compared to the as-extruded and over-aged alloys. The analysis showed that the excellent elevated temperature strengths of the peak-aged alloy are attributed to the LPSO phase strengthening and the grain refinement strengthening, and the role of the LPSO strengthening is related to not only its amount, but also its morphology.

关键词： Magnesium Mg-Dy-Zn alloy Microstructure Mechanical properties Long period stacking ordered phase

Perovskite intermediate phases fundamentally address the urgent stability issue

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Perovskite intermediate phases fundamentally address the urg...

Mixed-Cation Perovskite Ferroelectrics for Highly Polarization Sensitive Photodetection

第九届新型太阳能材料科学与技术学术研讨会

作者： weichuan zhang Huiqiong Zhou CAS Key Laboratory of Nanosystem and Hierachical Fabrication CAS Center for Excellence in Nanoscience National Center for Nanoscience and Technology University of Chinese Academy of Sciences

Although halide hybrid perovskite solar cells have been rapidly developed, their commercial implementation still needs to overcome the inevitable stability issue. Recently in Chem, Nan et al. discovered a key intermediate of 8 H phase which helps elucidate the complete phase evolution and stabilization mechanism of formamidinium-based perovskite. We further preview this recent finding on the phase evolution and stabilization mechanism of FA-based 3 D perovskites. On this basis, we also point out that a highly efficient and stable solar cell has been achieved by rationally controlling the factors such as composition, stoichiometry, additives, and precursor solution.

关键词： perovskite intermediate phases stability

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Mixed-Cation Perovskite Ferroelectrics for Highly Polarizati...

第九届新型太阳能材料科学与技术学术研讨会

作者： weichuan zhang Yuan zhang Huiqiong Zhou CAS Key Laboratory of Nanosystem and Hierarchical Fabrication CAS Center for Excellence in Nanoscience School of Chemistry Beijing Advanced Innovation Center for Biomedical EngineeringBeihang University

Linear dichroic anisotropic photonic materials are highly attractive due to their great potentials in many applications, which in combination with the ferroelectric properties could broaden their research and applications.1-3 Here, we propose a new ferroelectric design strategy: namely, partial organic cation substitution for precisely designing 1 D polarizationsensitive perovskite ferroelectrics. As an example, the 1 D mixed-cation perovskite ferroelectric(npropylammonium)(methylammonium)SbBr5 was synthesized, which exhibits a fascinating ferroelectricity with a notable reversible polarization of 2.9 μC/cm2 and a large ferroelectricity-driven polarization ratio of 6.9. Importantly, the single-crystalline photodetectors also exhibit superior optoelectronic anisotropic performances at the paraelectric phase, having a large photoelectric anisotropy ratio(～35), an excellent polarization-sensitive dichroism ratio(～1.31), highly sensitive detectivity up to ～109 Jones, and a fast response rate(～45/68 μs).

关键词： mixed-cation perovskite ferroelectric polarization sensitive photodetection

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基于自适应特征融合的小样本细粒度图像分类

计算机工程与应用 2023年第3期59卷 184-192页

作者：解耀华章为川任劼景军锋西安工程大学电子信息学院西安710600 陕西省人工智能联合实验室西安工程大学分部西安710600

现有的小样本学习算法未能充分提取细粒度图像的特征,导致细粒度图像分类准确率较低。为了更好地对基于度量的小样本细粒度图像分类算法中提取的特征进行建模,提出了一种基于自适应特征融合的小样本细粒度图像分类算法。在特征提取网络... 详细信息

现有的小样本学习算法未能充分提取细粒度图像的特征,导致细粒度图像分类准确率较低。为了更好地对基于度量的小样本细粒度图像分类算法中提取的特征进行建模,提出了一种基于自适应特征融合的小样本细粒度图像分类算法。在特征提取网络上设计了一种自适应特征融合嵌入网络,可以同时提取深层的强语义特征和浅层的位置结构特征,并使用自适应算法和注意力机制提取关键特征。在训练特征提取网络上采用单图训练和多图训练方法先后训练,在提取样本特征的同时关注样本之间的联系。为了使得同一类的特征向量在特征空间中的距离更加接近,不同类的特征向量的距离更大,对所提取的特征向量做特征分布转换、正交三角分解和归一化处理。提出的算法与其他9种算法进行实验对比,在多个细粒度数据集上评估了5 way 1 shot的准确率和5 way 5 shot的准确率。在Stanford Dogs数据集上的准确率提升了5.27和2.90个百分点,在Stanford Cars数据集上的准确率提升了3.29和4.23个百分点,在CUB-200数据集上的5 way 1 shot的准确率只比DLG略低0.82个百分点,但是5 way5 shot上提升了1.55个百分点。

关键词：小样本学习细粒度图像分类自适应特征融合注意力机制

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基于注意力机制的双度量小样本图像分类算法

国外电子测量技术 2022年第8期41卷 34-38页

作者：朱新源任劼章为川西安工程大学电子信息学院西安710048 格里菲斯大学综合智能系统研究所布里斯班4702

小样本图像分类旨在利用少数几个标记样本训练出一个具有良好泛化性网络,其中基于度量学习的小样本图像分类方法具有模型简单且高效的优点。针对图像到类度量的深度最近邻网络(deep nearest neighbor neural network, DN4),提出了基于... 详细信息

小样本图像分类旨在利用少数几个标记样本训练出一个具有良好泛化性网络,其中基于度量学习的小样本图像分类方法具有模型简单且高效的优点。针对图像到类度量的深度最近邻网络(deep nearest neighbor neural network, DN4),提出了基于注意力机制的双重度量网络(attention based bi-metric network, ABM-Net)。在主干网络中加入注意力机制以获得更有效的特征表示,并提出将图像到图像度量与图像到类度量结合的双度量模块。实验结果表明,相较于DN4,ABM-Net的性能在数据集CUB-200-2011、Stanford-Dogs和Stanford-Cars的1-shot和5-shot分类任务中均有一定的提升。

关键词：图像分类小样本学习度量学习注意力机制卷积神经网络

程序性死亡因子1/程序性死亡因子1配体抑制剂治疗肾细胞癌有效性及安全性的Meta分析

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中国全科医学 2023年第30期26卷 3815-3822,3832页

作者：张懂理沈冲张卫川陈海滨赵建军河北工程大学临床医学院河北省邯郸市056002 河北工程大学附属医院泌尿外二科河北省邯郸市056002

背景肾细胞癌因起病隐匿,缺乏早期典型的临床表现,多数患者确诊时已经发生转移或已到晚期,根治性肾细胞癌切除术疗效较差。近年来,随着靶向治疗在肿瘤治疗中广泛应用,很大程度上降低了术后复发率和死亡率,但由于存在一定的不良反应及并... 详细信息

背景肾细胞癌因起病隐匿,缺乏早期典型的临床表现,多数患者确诊时已经发生转移或已到晚期,根治性肾细胞癌切除术疗效较差。近年来,随着靶向治疗在肿瘤治疗中广泛应用,很大程度上降低了术后复发率和死亡率,但由于存在一定的不良反应及并发症,因而临床治疗的有效性及安全性缺乏循证依据。目的系统评价程序性死亡因子1(PD-1)/程序性死亡因子1配体(PD-L1)抑制剂治疗肾细胞癌的有效性及安全性。方法计算机检索中国知网、万方数据知识服务平台、维普网及PubMed、Web of Science、Embase、Cochrane Library、Clinical Trials英文数据库和手动检索以收集PD-1/PD-L1抑制剂治疗肾细胞癌的随机对照试验,试验组为接受PD-1/PD-L1抑制剂治疗,对照组为接受常规治疗或安慰剂。检索时间为建库至2022-09-30。由2位研究员独立提取和整理资料,依据Cochrane 5.3手册标准对纳入文献的质量进行评价,应用RevMan 5.4软件进行Meta分析。结果最终纳入11篇文献,研究对象7895例,试验组3936例,对照组3959例。Meta分析结果显示,试验组总生存期(OS)、无进展生存期(PFS)优于对照组〔HR=0.87,95%CI(0.84,0.90),P0.05,表明各研究间发表偏倚不显著。结论PD-1/PD-L1抑制剂治疗肾细胞癌可显著改善和提高患者的OS、PFS、ORR、PR、CR和DCR,其安全性较好,未增加患者的不良反应发生率,从而证实PD-1/PD-L1抑制剂治疗肾细胞癌在临床有效性及安全性方面有一定的优越性。

关键词：癌,肾细胞程序性细胞死亡受体1 免疫检查点抑制剂有效性安全性 Meta分析

Road map for, and technical challenges of, carbon-nanotube integrated circuit technology

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National Science Review 2024年第3期11卷 14-16页

作者： Jia Si Panpan zhang Zhiyong zhang Key Laboratory for the Physics and Chemistry of Nanodevices and Center for Carbon-based Electronics School of Electronics Peking University State Key Laboratory of Information Photonics and Optical Communications Beijing University of Posts and Telecommunications

The past decade has witnessed an explosion of research on carbon-nanotube(CNT) electronics due to their outstanding properties, including an ultrathin body, a high carrier mobility and a high saturation velocity.

关键词： TRANSISTORS

New structure transistors for advanced technology node CMOS ICs

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National Science Review 2024年第3期11卷 24-41页

作者： Qingzhu zhang Yongkui zhang Yanna Luo Huaxiang Yin Integrated Circuit Advanced Process R&D Center Institute of Microelectronics of Chinese Academy of Sciences(IMECAS) State key Lab of Fabrication Technologies for Integrated Circuits Institute of Microelectronics of Chinese Academy of Sciences School of Integrated Circuits University of Chinese Academy of Sciences

Over recent decades, advancements in complementary metal-oxide-semiconductor integrated circuits(ICs)have mainly relied on structural innovations in transistors. From planar transistors to the fin field-effect transistor(FinFET) and gate-all-around FET(GAAFET), more gate electrodes have been added to three-dimensional(3D) channels with enhanced control and carrier conductance to provide higher electrostatic integrity and higher operating currents within the same device footprint. Beyond the 1-nm node, Moore's law scaling is no longer expected to be applicable to geometrical shrinkage. Vertical transistor stacking, e.g. in complementary FETs(CFET), 3D stack(3DS) FETs and vertical-channel transistors(VFET), for enhanced density and variable circuit or system design represents a revolutionary scaling approach for sustained IC development. Herein, innovative works on specific structures, key process breakthroughs, shrinking cell sizes and design methodologies for transistor structure research and development are reviewed. Perspectives on future innovations in advanced transistors with new channel materials and operating theories are also discussed.

关键词： transistor CMOS GAAFET CFET 3DS FET