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Target decomposition and recognition from wide-angle SAR imaging based on a Gaussian amplitude-phase model

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Science China(Information Sciences) 2017年第6期60卷 212-224页

作者： Yongchen LI ya-qiu jin Key Laboratory for Information Science of Electromagnetic Waves Fudan University

Wide-angle synthetic aperture radar(W-SAR) imaging accounts for multi-azimuthal scattering and is feasible for retrieving more comprehensive features of complex targets. Because a typical target is seen as composed of its components(typically, some simple geometric objects), a Gaussian amplitude-phase(GAP)model has been developed for the analysis of multi-azimuthal scattering from these objects. Based on the timefrequency analysis of wide-angle scattering, the parameters of the GAP model were estimated, including the Gaussian variance, the surface curvature, and the number of objects in all imaged pixels. Numerical simulations and real measurements demonstrate the capability of the GAP model for decomposing and recognizing complex electric-large targets.

关键词： wide-angle SAR Gaussian amplitude-phase time-frequency target decomposition target recognition

Reciprocal translation between SAR and optical remote sensing images with cascaded-residual adversarial networks

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Science China(Information Sciences) 2021年第2期64卷 154-168页

作者： Shilei FU Feng XU ya-qiu jin Key Lab for Information Science of Electromagnetic Waves (MoE) Fudan University

Despite the advantages of all-weather and all-day high-resolution imaging, synthetic aperture radar(SAR) images are much less viewed and used by general people because human vision is not adapted to microwave scattering phenomenon. However, expert interpreters can be trained by comparing side-byside SAR and optical images to learn the mapping rules from SAR to optical. This paper attempts to develop machine intelligence that is trainable with large-volume co-registered SAR and optical images to translate SAR images to optical version for assisted SAR image interpretation. Reciprocal SAR-optical image translation is a challenging task because it is a raw data translation between two physically very different sensing modalities. Inspired by recent progresses in image translation studies in computer vision,this paper tackles the problem of SAR-optical reciprocal translation with an adversarial network scheme where cascaded residual connections and hybrid L1-GAN loss are employed. It is trained and tested on both spaceborne Gaofen-3(GF-3) and airborne Uninhabited Airborne Vehicle Synthetic Aperture Radar(UAVSAR) images. Results are presented for datasets of different resolutions and polarizations and compared with other state-of-the-art methods. The Frechet inception distance(FID) is used to quantitatively evaluate the translation performance. The possibility of unsupervised learning with unpaired/unregistered SAR and optical images is also explored. Results show that the proposed translation network works well under many scenarios and it could potentially be used for assisted SAR interpretation.

关键词： synthetic aperture radar generative adversarial network (GAN) image translation cascaded residual connection Frechet inception distance

Numerical simulation of tomographic-SAR imaging and object reconstruction using compressive sensing with L_(1/2)-norm regularization

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Chinese Science Bulletin 2014年第33期59卷 4600-4607页

作者： Xiao Wang Feng Xu ya-qiu jin Key Laboratory for Information Science of Electromagnetic Waves (MoE) Fudan University

By making use of multiple acquisitions of synthetic aperture radar(SAR) observations over the same area, tomographic-SAR(tomo-SAR) technology can achieve three-dimensional(3-D) imaging of the objects of interest. The compressive sensing(CS) approach has been applied to deal with the sparseness of the elevation *** to its sparsity and convexity, the L1-norm regularization, as an approximated L0-norm with an exact solution,has been employed in CS to reconstruct the reflectivity profile of the objects. In this paper, based on our studies on polarimetric scattering and SAR imaging simulations, we produce numerical multi-pass tomo-SAR observations of the terrain object. Then, we present the CS with novel L1/2-norm regularization to realize 3-D reconstruction. As a non-convex optimization problem, the L1/2-norm regularization is solved by an iterative algorithm. This numerical simulation of tomo-SAR imaging and 3-D reconstruction of the object modeling can be of great help for parameterized analysis of tomo-SAR imagery. As an example, a tomo-SAR image and 3-D reconstruction of the Beijing National Stadium model are presented.

关键词： SAR成像 L1范数数值模拟压缩断层正规化 SAR图像三维重建

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Parameter Inversions of Multi-Layer Media of Mars Polar Region with Validation of SHARAD Data

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International Journal of Astronomy and Astrophysics 2019年第3期9卷 335-353页

作者： Chuan Liu ya-qiu jin Key Laboratory for Information Science of Electromagnetic Waves (MoE) Fudan University Shanghai China

HF (high frequency) radar sounder technology has been developed for several missions of Mars surface/subsurface exploration. This paper presents a model of rough surface and stratified sub-surfaces to describe the multi-layer structure of Mars polar deposits. Based on numerical simulation of radar echoes from rough surface/stratified interfaces, an inversion approach is developed to obtain the parameters of Polar Layered Deposits, i.e. layers thickness and dielectric constants. As a validation example, the SHARAD radar sounder data of the Promethei Lingula of Mars South Polar region is adopted for parameters inversion. The result of stratification is also analyzed and compared with the optical photo of the deep cliff of Chasma Australe canyon. Dielectric inversions show that the deposit media are not uniform, and the dielectric constants of the Promethei Lingula surfaces are large, and become reduced around the depth of 20 m - 30 m, below where most of the deposits are nearly pure ice, except a few thin layers with a lot of dust.

关键词： Radar Sounder Inversion of Multi-Layer Parameters Stratified Media Mars Polar Region SHARAD

Polarized Scattering from Random Clusters of Spatially-oriented,Non-spherical Scatterers

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Polarized Scattering from Random Clusters of Spatially-orien...

AAV2-PDE6B restores retinal structure and function in the retinal degeneration 10 mouse model of retinitis pigmentosa by promoting phototransduction and inhibiting apoptosis

1997 International Symposium on Radio Propagation(ISRP’97)

作者： ya-qiu jin Xingzhong Huang Wave Scattering and Remote Sensing Center and Department of Electronic Engineering Fudan University

＜正＞Employing multiple scattering formulation of T-matrix method, numerical simulations are developed and applied to polarized scattering from random clusters of spatially-oriented,non-spherical *** scattering are numerically calculated for the functional dependence on particle shape,size,spatial distribution,orientation and other physical parameters. Comparisons between collective scattering from clusters and independent scattering from sparsely random particles are numerically derived.

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Neural Regeneration Research 2025年第8期20卷 2408-2419页

作者： Ruiqi qiu Mingzhu yang Xiuxiu jin jingyang Liu Weiping Wang Xiaoli Zhang jinfeng Han Bo Lei Henan Eye Hospital Henan Provincial People’s HospitalPeople’s Hospital of Zhengzhou UniversityZhengzhouHenan ProvinceChina Eye Institute Henan Academy of Innovations in Medical ScienceZhengzhouHenan ProvinceChina Branch of National Clinical Research Center for Ocular Disease Henan Provincial People’s HospitalZhengzhouHenan ProvinceChina Academy of Medical Science Zhengzhou UniversityZhengzhouHenan ProvinceChina

Retinitis pigmentosa is a group of inherited diseases that lead to retinal degeneration and photoreceptor cell ***,there is no effective treatment for retinitis pigmentosa caused by PDE6B ***-associated virus(AAV)-mediated gene therapy is a promising strategy for treating retinitis *** aim of this study was to explore the molecular mechanisms by which AAV2-PDE6B rescues retinal *** do this,we injected retinal degeneration 10(rd10)mice subretinally with AAV2-PDE6B and assessed the therapeutic effects on retinal function and structure using dark-and light-adapted electroretinogram,optical coherence tomography,and ***-independent acquisition-mass spectrometry-based proteomic analysis was conducted to investigate protein expression levels and pathway enrichment,and the results from this analysis were verified by real-time polymerase chain reaction and western ***2-PDE6B injection significantly upregulated PDE6βexpression,preserved electroretinogram responses,and preserved outer nuclear layer thickness in rd10 *** expressed proteins between wild-type and rd10 mice were closely related to visual perception,and treating rd10 mice with AAV2-PDE6B restored differentially expressed protein expression to levels similar to those seen in wild-type *** Encyclopedia of Genes and Genome analysis showed that the differentially expressed proteins whose expression was most significantly altered by AAV2-PDE6B injection were enriched in phototransduction ***,the phototransductionrelated proteins Pde6α,Rom1,Rho,Aldh1a1,and Rbp1 exhibited opposite expression patterns in rd10 mice with or without AAV2-PDE6B ***,Bax/Bcl-2,p-ERK/ERK,and p-c-Fos/c-Fos expression levels decreased in rd10 mice following AAV2-PDE6B *** data suggest that AAV2-PDE6B-mediated gene therapy promotes phototransduction and inhibits apoptosis by inhibiting the ERK signaling pathway and upr

关键词： apoptosis AAV2-PDE6B ERK1/2 gene therapy phototransduction proteomics rd10 retinitis pigmentosa

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Unlocking the stable interface in aqueous zinc-ion battery with multifunctional xylose-based electrolyte additives

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Journal of Energy Chemistry 2025年第1期100卷 770-778页

作者： Xiaoqin Li Jian Xiang Lu qiu Xiaohan Chen Yinkun Zhao Yujue Wang Qu Yue Taotao Gao Wenlong Liu Dan Xiao Zhaoyu jin Panpan Li Institute for Advanced Study Chengdu University School of Mechanical Engineering Chengdu University College of Food and Biological Engineering Chengdu University Institute of Fundamental and Frontier Sciences University of Electronic Science and Technology of China College of Materials Science and Engineering Sichuan University

The growth of dendrites and the side reactions occurring at the Zn anode pose significant challenges to the commercialization of aqueous Zn-ion batteries（AZIBs）. These challenges arise from the inherent conflict between mass transfer and electrochemical kinetics. In this study, we propose the use of a multifunctional electrolyte additive based on the xylose（Xylo） molecule to address these issues by modulating the solvation structure and electrode/electrolyte interface, thereby stabilizing the Zn anode. The introduction of the additive alters the solvation structure, creating steric hindrance that impedes charge transfer and then reduces electrochemical kinetics. Furthermore, in-situ analyses demonstrate that the reconstructed electrode/electrolyte interface facilitates stable and rapid Zn2+ion migration and suppresses corrosion and hydrogen evolution reactions. As a result, symmetric cells incorporating the Xylo additive exhibit significantly enhanced reversibility during the Zn plating/stripping process, with an impressively long lifespan of up to 1986 h, compared to cells using pure ZnSO4electrolyte. When combined with a polyaniline cathode, the full cells demonstrate improved capacity and long-term cyclic stability. This work offers an effective direction for improving the stability of Zn anode via electrolyte design, as well as highperformance AZIBs.

关键词： Solvation

Dendrimer Effects Based on Microenvironment of Metallodendrimers

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Dendrimer Effects Based on Microenvironment of Metallodendri...

中国化学会第四届有机化学学术会议

作者： LIU, Wei-Guo CUI, Xin Huang, qiu-ya ZHU, jin DENG, jin-Gen Key Laboratory of Asymmetric Synthesis & Chirotechnology of Sichuan Province and Union Laboratory of Asymmetric Syntbesis, Chengdu Institute of Organic Chemistry, Chinese Academy of Sciences, Chengdu 610041, China. Chinese Academy of Sciences, Beijing China. Graduate School of the Academy of Sciences, Beijing, China

＜正＞The size of a dendrimer is roughly comparable to that of many enzymes and, just like enzymes, dendrimers are able to create a microenvironment around reactive site. While nature has had a ample opportunity to optimize enzymes through evolutionary processes, one of our best tools for the optimization of dendrimers is mimicry, even if based on grossly simplified models significant advances have been made in the last few years and more sophisticated dendritic

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基于类名引导的弱监督文本分类

计算机工程与设计 2023年第8期44卷 2329-2336页

作者：周悦尧奚雪峰崔志明盛胜利仇亚进苏州科技大学电子与信息工程学院江苏苏州215000 苏州市科技局苏州市虚拟现实智能交互及应用重点实验室江苏苏州215000 苏州科技大学苏州智慧城市研究院江苏苏州215000 德州理工大学计算机学院得克萨斯州拉伯克市79401

针对弱监督文本分类过于依赖专家生成种子词的局限,提出一种基于类名引导生成种子词的弱监督文本分类方法。使用Skip-Gram模型学习单词的向量表示,借助vMF(von Mises Fisher)分布对用户提供的类名与语料库之间的关系进行建模,综合考虑... 详细信息

针对弱监督文本分类过于依赖专家生成种子词的局限,提出一种基于类名引导生成种子词的弱监督文本分类方法。使用Skip-Gram模型学习单词的向量表示,借助vMF(von Mises Fisher)分布对用户提供的类名与语料库之间的关系进行建模,综合考虑语义相关性和语义特异性,由此生成一组高质量的种子词,无需依赖专家经验;迭代使用种子词生成伪标签和文档分类器;扩展种子词,进一步提升模型性能。在NYT和20 Newsgroups两个公开数据集上的实验结果(F1-score)表明了所提弱监督文本分类方法的有效性。

关键词：弱监督文本分类词向量冯米塞尔分布语义相关性语义特异性深度学习

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