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一种抑制SAR图像中动目标干扰的方法

西安电子科技大学学报 2017年第2期44卷 8-13页

作者：肖力李学仕孙光才邢孟道西安电子科技大学雷达信号处理国家重点实验室陕西西安710071 西安电子科技大学信息感知技术协同创新中心陕西西安710071

在高分辨率宽测绘带合成孔径雷达系统中,用传统的静止场景成像方法对存在动目标的回波数据进行成像,动目标在得到的合成孔径雷达图像中是散焦的,并且动目标会聚焦到错误的位置,同时,散焦的动目标会掩盖原本的合成孔径雷达场景.利用传统... 详细信息

在高分辨率宽测绘带合成孔径雷达系统中,用传统的静止场景成像方法对存在动目标的回波数据进行成像,动目标在得到的合成孔径雷达图像中是散焦的,并且动目标会聚焦到错误的位置,同时,散焦的动目标会掩盖原本的合成孔径雷达场景.利用传统的空时自适应处理方法对合成孔径雷达图像中散焦的动目标进行抑制时,所需的空间自由度为场景中动目标的个数与脉冲重复频率欠采样数的乘积,这在实际中很难得到满足.为解决这一问题,提出了一种基于方位Deramp处理的空时自适应处理方法.该方法首先对合成孔径雷达回波数据进行方位Deramp处理,使得动目标在空时平面中是粗聚焦的,此时,抑制合成孔径雷达图像中的一个动目标只需要一个空间自由度.当合成孔径雷达图像中存在多个动目标时,提出了动态导向矢量的概念,它能有效地减少抑制合成孔径雷达图像中散焦动目标所需的空间自由度数目.

关键词：高分辨率宽测绘带(HRWS)SAR Deramp 空时自适应处理方法动态导向矢量

Efficient large-area flexible organic photovoltaic modules on transparent thin silver electrodes

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Science China Chemistry 2025年

作者： Cong Xie Zedong Xiong Xinlu Liu Wen Wang Yang Liu xueshi Jiang Xin Lu Lulu sun Yinhua Zhou Wuhan National Laboratory for Optoelectronics Huazhong University of Science and Technology Kunming Institute of Physics

Large-area flexible organic photovoltaic（OPV） modules are challenging to achieve high power conversion efficiency（PCE）.Electrical shunts or shortages generally occur in large-area OPV modules due to the ultrathin（100–200 nm） and soft active layers. Improving the surface smoothness of bottom transparent electrode will be able to suppress the shunts and shortages. In this work, we report a method to fabricate smooth and flexible transparent electrodes based on thin silver film, and further to fabricate efficient large-area flexible OPV modules. The fabricated thin silver transparent electrodes simultaneously have high conductivity, high optical transmittance, good mechanical flexibility and low surface roughness. Humidity exposure（h.e.）treatment on MoO3effectively facilitates the continuous growth of the thin transparent silver electrode. 6 nm silver film on MoO3（h.e.） on plastic substrate shows a transmittance up to 89%, a sheet resistance of 15 Ω/sq, and a low surface roughness with a rootmean-square value of 0.276 nm. Furthermore, 52-cm2flexible organic solar modules（15 subcells） showed a certified PCE of12.66%. Furthermore, a 1350 cm2flexible component assembled by 25 pieces of 52–55 cm2modules showed certified PCE of12.10% with an open-circuit voltage of 62.85 V.

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电法勘探在煤矿中的应用

物探与化探 1984年第2期 116-120页

作者：孙学诗河北峰峰矿务局

电法勘探，已广泛应用于寻找金属矿、石油、煤田及地下水源的勘探中，并已成为主要的物探方法之一。近几年来，由于煤炭工业生产的迅速发展，电法勘探在煤炭能源开发中也获得了广泛的

关键词：电法勘探采煤活动电剖面曲线类型测深地球物理勘探水深测量电测深曲线隐伏断层

NICU母婴分离患儿未行母乳喂养的原因分析

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护理研究（中旬版） 2017年第10期31卷 3731-3734页

作者：曾靓妮陈涛蓉孙雪诗四川大学华西第二医院护师610000

[目的]探讨NICU母婴分离早产儿未行母乳喂养的原因与对策。[方法]采用母婴分离早产儿未行母乳喂养原因调查表和母乳喂养自信心量表对入住NICU的患儿母亲进行调查。[结果]162例患儿中,母乳喂养组49例,未行母乳喂养组113例;母乳喂养组患... 详细信息

[目的]探讨NICU母婴分离早产儿未行母乳喂养的原因与对策。[方法]采用母婴分离早产儿未行母乳喂养原因调查表和母乳喂养自信心量表对入住NICU的患儿母亲进行调查。[结果]162例患儿中,母乳喂养组49例,未行母乳喂养组113例;母乳喂养组患儿母亲母乳喂养自信心总得分(121.31分±19.02分)高于未行母乳喂养组(112.28分±25.19分),两组比较差异有统计学意义(P<0.05);未行母乳喂养组未提供母乳的原因主要是因母亲自身疾病原因、正在服用特殊药物不能提供母乳(占46.0%);因过度焦虑、担心患儿、乳房胀痛、食欲下降等原因导致乳汁分泌过少(占44.2%);因住家过远无法送母乳(占30.1%);认为送的母乳可能会被污染,导致患儿腹泻(占17.7%)。[结论]医疗机构应注重母婴分离时的母乳喂养宣教,为患儿母亲提供有效泌乳技巧支持,提高母乳喂养自信心,以提高母婴分离患儿的母乳喂养率。

关键词：早产儿母婴分离母乳喂养母乳喂养自信心健康宣教泌乳技巧

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伺服系统传递函数的全数字测量方法

电子测量技术 2010年第9期33卷 8-10页

作者：刘金星李洪文年朋孙学士中国科学院长春光学精密机械与物理研究所长春130033 中国科学院研究生院北京100039 吉林大学通信工程学院长春130025

在设计伺服控制系统时为了得到更好的控制精度,经常需要知道被控系统的传递函数。为了得到更简便的测定方法,本文介绍了基于全数字模式的频域测定法,在基于传统自动控制理论测量传递函数的基础上,省略了频率分析仪、测速机和示波器等设... 详细信息

在设计伺服控制系统时为了得到更好的控制精度,经常需要知道被控系统的传递函数。为了得到更简便的测定方法,本文介绍了基于全数字模式的频域测定法,在基于传统自动控制理论测量传递函数的基础上,省略了频率分析仪、测速机和示波器等设备,并于文中实验部分给出了被控对象的实验记录测量数据及其开环幅频特性曲线bode图。最后,以此实验结果及MATLAB仿真结果对比分析表明,此方法成功的实现了全数字测定被控系统的传递函数,具有一定的推广型。

关键词：传递函数编码器 MATLAB 频域数字测定

Molecular dynamics simulations of microstructure and dislocation evolution of single-crystal Ni-based superalloys under femtosecond laser loading

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Progress in Natural Science:Materials International 2024年第5期34卷 942-954页

作者： Peng Shen Xuesong Mei Tao sun xueshi Zhuo Xiaomao sun Wenjun Wang Jianlei Cui Zhengjie Fan School of Mechanical Engineering Xi'an Jiaotong University State Key Laboratory for Manufacturing System Engineering Xi'an Jiaotong University Shaanxi Key Laboratory of Intelligent Robots Xi'an Jiaotong University

In this paper, molecular dynamics simulations are employed to investigate the temperature, stress distribution, microstructure and evolution of dislocations in singlecrystal Ni-based superalloys during femtosecond laser drilling of micro-holes. The results indicate that the temperature and stress variations in the model system increase with the increment of laser energy density. The pulse width has a relatively low effect on temperature and stress variations. At the same time, an increase in dislocations is primarily related to energy density and stress distribution. The number of dislocations increases with the energy density, with the 1/6 dislocation showing the highest increase ratio. The densest concentration of dislocations occurs at the hole walls. Dislocations and stacking faults gradually penetrate the precipitate phase under the influence of temperature and reach a stable state as the relaxation time increases. The above research findings provide important theoretical guidance for understanding the microstructure evolution and changes in the mechanical properties of single-crystal Ni-based superalloys during femtosecond laser processing of micro-holes.

关键词： Molecular dynamics

Efficient nonfullerene organic solar cells with active layers fabricated by water transfer printing

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Journal of Energy Chemistry 2019年第10期28卷 220-224页

作者： Lulu sun xueshi Jiang Yinhua Zhou Wuhan National Laboratory for Optoelectronics and School of Optical and Electronic Information Huazhong University of Science and Technology

Preparation of high-quality films plays an important role to achieve high-performance nonfullerene (NF) organic solar cells. NF active layer films are typically fabricated by spin coating. Novel fabrication methods to process the NF active layer are desirable to be compatible with large-area production. Herein, we report on the fabrication of NF active layer films via a water transfer printing *** method delivers a uniform film with controllable film thicknesses. NF active layers of PDBD-T:ITIC and PBDB-T-2F:IT-4F were fabricated via the method to validate its effectiveness. Solar cells with the water transfer-printed active layers show comparable performance (up to 11.7%) to the cells with spin-coated active layers. Furthermore, NF solar modules containing 4-sub cells with the active area of 3.2 cm2 are also fabricated via the method. The module shows VOC of up to 3.4 V and a power conversion efficiency of 8.1% with the PBDB-T-2F:IT-4F active layer.

关键词： Nonfullerene organic solar cells Water transfer printing Film fabrication Solar module

Dual-resonance enhanced quantum light-matter interactions in deterministically coupled quantum-dot-micropillars

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Light(Science & Applications) 2021年第9期10卷 1680-1686页

作者： Shunfa Liu Yuming Wei xueshi Li Ying Yu Jin Liu Siyuan Yu Xuehua Wang State Key Laboratory of Optoelectronic Materials and Technologies School of PhysicsSchool of Electronics and Information TechnologySun Yat-sen UniversityGuangzhou510275China Photonics Group Merchant Venturers School of EngineeringUniversity of BristolBristolBS81UBUK

Optical microcavities have widely been employed to enhance either the optical excitation or the photon emission processes for boosting light-matter interactions at the *** both the excitation and emission processes are simultaneously facilitated by the optical resonances provided by the microcavities,as referred to the dual-resonance condition in this article,the performances of many nanophotonic devices approach to the *** this work,we present versatile accessing of dual-resonance conditions in deterministically coupled quantum-dot(QD)-micropillars,which enables emission from neutral exciton(X)—charged exciton(CX)transition with improved single-photon *** addition,the rarely observed up-converted single-photon emission process is achieved under dual-resonance *** further exploit the vectorial nature of the high-order cavity modes to significantly improve the excitation efficiency under the dual-resonance *** dual-resonance enhanced light-matter interactions in the quantum regime provide a viable path for developing integrated quantum photonic devices based on cavity quantum electrodynamics(QED)effect,e.g.,highly efficient quantum light sources and quantum logical gates.

关键词： quantum resonance excitation

Efficient second harmonic generation by harnessing bound states in the continuum in semi-nonlinear etchless lithium niobate waveguides

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Light(Science & Applications) 2022年第11期11卷 2774-2781页

作者： xueshi Li Jiantao Ma Shunfa Liu Peinian Huang Bo Chen Dunzhao Wei Jin Liu State Key Laboratory of Optoelectronic Materials and Technologies School of PhysicsSun Yat-Sen University510275 GuangzhouChina

Integrated photonics provides unprecedented opportunities to pursue advanced nonlinear light sources with lowpower consumptions and small footprints in a scalable manner,such as microcombs,chip-scale optical parametric oscillators and integrated quantum light *** a variety of nonlinear optical processes,high-efficiency second harmonic generation(SHG)on-chip is particularly appealing and yet *** this work,we present efficient SHG in highly engineerable semi-nonlinear waveguides consisting of electron-beam resist waveguides and thin-film silicon nitride(SiN)/lithium niobate(LN).By carefully designing octave-separating bound states in the continuum(BICs)for the nonlinear interacting waves in such a hybrid structure,we have simultaneously optimized the losses for both fundamental frequency(FF)and second harmonic(SH)waves and achieved modal phasing matching and maximized the nonlinear modal overlap between the FF and SH waves,which results in an experimental conversion efficiency up to 4.05%W^(-1)cm^(-2).Our work provides a versatile and fabrication-friendly platform to explore on-chip nonlinear optical processes with high effciency in the context of nanophotonics and quantum optics.

关键词： nonlinear harmonic lithium