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1.3.μm 4×25-Gb/s hybrid integrated TOSA and ROSA

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Frontiers of information Technology & Electronic engineering 2019年第4期20卷 490-497页

作者： Yu LIU Hao-tian BAO Yi-ming zhang Zhi-ke zhang Yun-shan zhang Xiang-fei CHEN {3. LU Yue-chun SHI Jia-shun zhang Liang-liang WANG {3.-ming AN Ning-hua ZHU State Key Laboratory on Integrated Optoelectronics Institute of Semiconductors Chinese Academy of Sciences school of Electronic Electrical and Communication Engineering University of Chinese Academy of Sciences State Key Laboratory of Advanced Optical Communications System and Networks School of Electronics Engineering and Computer Science Peking University Microwave-Photonics Technology Laboratory College of Engineering and Applied Sciences Nanjing University

The design and fabrication of a compact and low-cost 4×25-Gb/s transmitter optical sub-assembly(TOSA) and receiver optical sub-assembly(ROSA) using a hybrid integrated technique are reported. TOSA and ROSA are developed without thermoelectric cooler for coarse wavelength division multiplexing applications. Physical dimension of the packaged optical subassembly is limited to 11.5 mm×5.4 mm×5.4 mm. The design of TOSA and ROSA is employed using a silica-based arrayed waveguide grating chip to select the specific channel wavelength at O-band. In TOSA, the wavelength of four 1.3.μm discrete directly modulated laser chips is well controlled based on the reconstruction equivalent chirp technique. In the back-to-back transmission test, bit error rates for all lanes of cascade of the TOSA and ROSA are small. A clear opening eye diagram is obtained.

关键词： Reconstruction equivalent chirp Arrayed waveguide grating Transmitter optical subassembly Hybrid integrated

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基于智能进化算法的可见水印对抗攻击

计算机工程与科学 2024年第1期46卷 63-71页

作者：季俊豪张玉书赵若宇温文媖董理南京航空航天大学计算机科学与技术学院江苏南京211106 江西财经大学信息管理学院江西南昌330032 宁波大学信息科学与工程学院浙江宁波315000

随着公民版权意识的提高,越来越多含有水印的图像出现在生活中。然而,现有的研究表明,含有水印的图像会导致神经网络分类错误,这对神经网络的普及和应用构成了巨大的威胁。对抗训练是解决这类问题的防御方法之一,但是需要使用大量的水... 详细信息

随着公民版权意识的提高,越来越多含有水印的图像出现在生活中。然而,现有的研究表明,含有水印的图像会导致神经网络分类错误,这对神经网络的普及和应用构成了巨大的威胁。对抗训练是解决这类问题的防御方法之一,但是需要使用大量的水印对抗样本作为训练数据。为此,提出了一种基于智能进化算法的可见水印对抗攻击方法来生成高强度的水印对抗样本。该方法不仅能快速生成水印对抗样本,而且还能使其最大程度地攻击神经网络。此外,该方法还加入了图像质量评价指标来约束图像的视觉损失,从而使水印对抗样本更加美观。实验结果表明,所提方法相比于基准水印攻击方法时间复杂度更低,相比于基准黑盒攻击对神经网络攻击成功率更高。

关键词：对抗攻击水印图像质量评价指标优化神经网络

面向全息MIMO 6G通信的电磁信道建模理论与方法

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电子与信息学报 2024年第5期46卷 1940-1950页

作者：黄崇文季然魏丽宫铁瑞陈晓明沙威杨军张朝阳 Yuen Chau 浙江大学信息与电子工程学院杭州310027 新加坡科技与设计大学新加坡487372 西安交通大学信息与通信工程学院西安710049 中兴通讯股份有限公司深圳518000 新加坡南洋理工大学新加坡639798

全息多输入多输出(HMIMO)是6G通信中的新兴技术,相应阵列由固定物理孔径下的密布天线单元组成。全息MIMO是电磁约束下Massive MIMO天线技术的拓展。全息MIMO系统在有效提升无线通信性能方面具有极大的潜力。比如,可用最小的功率损耗实... 详细信息

全息多输入多输出(HMIMO)是6G通信中的新兴技术,相应阵列由固定物理孔径下的密布天线单元组成。全息MIMO是电磁约束下Massive MIMO天线技术的拓展。全息MIMO系统在有效提升无线通信性能方面具有极大的潜力。比如,可用最小的功率损耗实现尽可能大的连续孔径,灵活控制目标方向的电磁波传输等。但是,由于全息MIMO系统包含大量的紧密分布的天线单元,且单元之间的距离小于半波长,因而造成严重的电磁耦合作用。这些耦合使传统的独立同分布的信道假设失效。因此,如何设计一个有效且贴近实际的信道建模成为当前全息MIMO研究中最具挑战性的问题之一。针对该挑战,该文研究了基于电磁场理论的4种信道建模方式,它们都能很好描述全息MIMO系统中的电磁波传输特征。第1种是基于平面格林函数的精确信道建模方式,该方式将自由空间中点对点的格林函数扩展到平面之间积分形式的格林函数,通过积分计算来构造两个全息MIMO平面之间的通信信道,但该方法的复杂度较高。第2, 3.方法则分别采用了平面波展开和球面波展开来近似全息MIMO的通信信道,这两种方案的复杂度更低。其中,基于平面波展开的信道建模形式相对简单,更适用于远场,但是会低估单元强耦合时的最大系统容量;基于球面波展开的信道建模能更好捕捉电磁波信道几何特征,但其复杂度较高。最后介绍基于随机格林函数的信道建模方法,主要描述富散射环境或瑞利信道中电磁波的随机特性。

关键词：全息MIMO通信电磁波理论信道建模

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有机薄膜晶体管陷阱态密度检测研究进展

激光与光电子学进展 2024年第13期61卷 45-57页

作者：李尧王奋强王爱玲蓝俊刘良朋吴回州张鹏杰兰州交通大学电子与信息工程学院甘肃兰州730070

近年来,有机薄膜晶体管取得了重大进步,推动了微电子电路、有机发光显示器、有机生物电子和有机光电探测器等技术的发展与应用。多晶或非晶的有机半导体易产生大量缺陷,器件的制备工艺也会带来缺陷,导致带隙中的局域陷阱态捕获电荷载流... 详细信息

近年来,有机薄膜晶体管取得了重大进步,推动了微电子电路、有机发光显示器、有机生物电子和有机光电探测器等技术的发展与应用。多晶或非晶的有机半导体易产生大量缺陷,器件的制备工艺也会带来缺陷,导致带隙中的局域陷阱态捕获电荷载流子。因此,陷阱态将严重影响有机薄膜晶体管中载流子的传输。综述了几种测量和表征有机半导体器件陷阱态密度的方法和技术,不同的方法基于不同的近似和假设,采用不同的测量原理,涵盖不同的能量范围。对比分析了几种检测方法的优势和局限性,对有机薄膜陷阱态的测量提出了具有指导性的意见。

关键词：有机薄膜晶体管陷阱态密度载流子有机半导体检测方法

Exploration of the rare-earth cobalt nickel-based magnetocaloric materials for hydrogen liquefaction

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Journal of Materials Science & Technology 2023年第28期159卷 163-169页

作者： Yikun zhang Jiayu Ying Xinqiang Gao Zhaojun Mo jun Shen Lingwei Li school of electronics and information&Key Laboratory of Novel Materials for Sensor of Zhejiang Province Hangzhou Dianzi UniversityHangzhou 310012China Ganjiang Innovation Academy Chinese Academy of SciencesGanzhou 341119China

Magnetic refrigeration based on the magnetocaloric effect(MCE)of magnetic solids has been considered as an emerging technology for hydrogen ***,the lack of high-performance materials has slowed the development of any practical ***,we present a family of rare-earth cobalt nickel-based magnetocaloric materials,namely Dy_(1-x)Ho_(x)CoNi and Ho_(1-x)Er_(x)CoNi compounds,and system-atically investigated their structural and magnetic properties as well as the MCE and magnetocaloric *** of these compounds crystallize in the C15-type Laves-phase structure and undergo typi-cal second-order magnetic phase transition(MPT).The change in magnetism and the MPT temperature for the Dy_(1-x)Ho_(x)CoNi and Ho_(1-x)Er_(x)CoNi compounds originate from the exchange interactions between nearest-neighbor RE 3.ion *** hysteresis magnetocaloric effect was achieved,and the MPT tem-perature of these compounds could be tuned from the liquefaction temperature of nitrogen(∼77 K)to hydrogen(∼20 K)by adjusting the ratio of rare-earth *** study’s findings indicate that theDy_(1-x)Ho_(x)CoNi and Ho_(1-x)Er_(x)CoNi compounds are of potential for practical magnetic refrigeration applica-tions in the field of hydrogen liquefaction.

关键词： Magnetocaloric effect Hydrogen liquefaction Rare earth Magnetocaloric performance Magnetic refrigeration

Sea fog detection based on unsupervised domain adaptation

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Chinese Journal of aeronautics 2022年第4期35卷 415-425页

作者： Mengqiu XU Ming WU jun GUO Chuang zhang Yubo WANG Zhanyu MA school of Artificial Intelligence Beijing University of Posts and TelecommunicationsBeijing 100876China International school Beijing University of Posts and TelecommunicationsBeijing 100876China

Sea fog detection with remote sensing images is a challenging task. Driven by the different image characteristics between fog and other types of clouds, such as textures and colors, it can be achieved by using image processing methods. Currently, most of the available methods are datadriven and relying on manual annotations. However, because few meteorological observations and buoys over the sea can be realized, obtaining visibility information to help the annotations is difficult. Considering the feasibility of obtaining abundant visible information over the land and the similarity between land fog and sea fog, we propose an unsupervised domain adaptation method to bridge the abundant labeled land fog data and the unlabeled sea fog data to realize the sea fog detection. We used a seeded region growing module to obtain pixel-level masks from roughlabels generated by the unsupervised domain adaptation model. Experimental results demonstrate that our proposed method achieves an accuracy of sea fog recognition up to 99.17%, which is nearly 3. higher than those vanilla methods.

关键词： Deep learning Sea fog detection Seeded region growing Transfer learning Unsupervised domain adaptation

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未知环境下GNSS辅助视觉自主定位方法

郑州航空工业管理学院学报 2024年第2期42卷 65-71页

作者：代君王敬宇闵君陈旭赵黎龙张春凤郑州航空工业管理学院航空宇航学院河南郑州450046 战略支援部队信息工程大学地理空间信息学院河南郑州450046 郑州航空工业管理学院河南省通用航空工程技术研究中心河南郑州450046

自主导航与定位是无人系统智能化的基础,未知环境下持续、稳定、可靠的位置服务对自主导航与定位尤为重要。针对低置信度下GNSS信号微弱、突防能力差、易受干扰而无法持续定位的问题,文章提出了一种GNSS辅助视觉自主动态定位方法,可以... 详细信息

自主导航与定位是无人系统智能化的基础,未知环境下持续、稳定、可靠的位置服务对自主导航与定位尤为重要。针对低置信度下GNSS信号微弱、突防能力差、易受干扰而无法持续定位的问题,文章提出了一种GNSS辅助视觉自主动态定位方法,可以在未知环境下提供全局定位服务。该方法以三帧影像及其对应的GNSS坐标作为约束数据,通过Horn坐标变换得到GNSS坐标系和世界坐标系转换矩阵;通过对极几何、单应变换、2D-3.位姿解算,得到后续影像序列在世界坐标系的相对位姿;最终得到GNSS不可用时无人载体在GNSS坐标系的全局位置数据。数据集验证表明,该算法适用于GNSS信号间歇性存在的情况,可以提供全局位置服务,且短时定位精度较高。进一步对比传统状态估计和BA优化后误差,结果表明,相比于传统状态估计,BA优化后定位精度提高10%—20%,证明了在未知环境下该算法具有良好的可靠性和适用性。

关键词：视觉定位 GNSS辅助定位 BA优化 Horn坐标变换

Progress in bionic information processing techniques for an electronic nose based on olfactory models

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Chinese Science Bulletin 2009年第4期54卷 521-534页

作者： LI Guang FU jun zhang Jia ZHENG junBao State Key Laboratory of Industrial Control Technology Zhejiang University Hangzhou 310027 China Department of Biomedical engineering Zhejiang University Hangzhou 310027 China Sir Run Run Shaw Hospital Affiliated with the School of Medicine Zhejiang University Hangzhou 310016 China Faculty of Informatics and electronics Zhejiang Sci-Tech University Hangzhou 310018 China

As a novel bionic analytical technique, an electronic nose, inspired by the mechanism of the biological olfactory system and integrated with modern sensing technology, electronic technology and pattern recognition technology, has been widely used in many areas. Moreover, recent basic research findings in biological olfaction combined with computational neuroscience promote its development both in methodology and application. In this review, the basic information processing principle of biological olfaction and artificial olfaction are summarized and compared, and four olfactory models and their applications to electronic noses are presented. Finally, a chaotic olfactory neural network is detailed and the utilization of several biologically oriented learning rules and its spatiotemporal dynamic propties for electronic noses are discussed. The integration of various phenomena and their mechanisms for biological olfaction into an electronic nose context for information processing will not only make them more bionic, but also perform better than conventional methods. However, many problems still remain, which should be solved by further cooperation between theorists and engineers.

关键词：电子鼻子嗅觉系统嗅觉模型图像识别仿生学

Double Peak Derived from Piezoelectric Coefficient Nonlinearity and Proposal for Self-Powered Systems

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Transactions of Nanjing University of aeronautics and astronautics 2018年第1期35卷 109-115页

作者： zhang Bin Li Dezhi Li Yingrui ducharne Benjamin Gao jun school of Mechanical Electrical & InformationShandong University school of Mechatronics engineering Harbin Institute of Technology Laboratoire de Génie Electrique et Ferroélectricité(LGEF) INSA de Lyon

With the development of wireless sensor network(WSN)applications in intelligent monitoring,additional support for the low power consumption wireless nodes can be provided by piezoceramics that harvest vibrational ***,we describe the effects of stimulation variations on piezoceramics and the energy harvesting circuit *** types of piezoceramics were stimulated at different frequencies and amplitudes to obtain the power output ***,the energy harvesting circuit was studied and coupled with the piezoceramics.A double peak phenomenon was found in energy harvesting using a hard piezoceramic which gave a direct proof that the nonlinearity of the piezo constant should be considered in ***,energy storage and output were studied and *** components for the WSN were recommended according to the output power and the *** results will give an instruction for piezoceramic energy harvesting under various stress amplitudes on its implementation.

关键词： piezoelectric energy harvesting self-powered system energy harvesting circuit output optimization