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Screening COVID-19 from chest X-ray images by an optical diffractive neural network with the optimized F number

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Photonics Research 2024年第7期12卷 1410-1426页

作者： JIALONG WANG SHOUYU CHAI WENTING GU BOYI LI XUE JIANG YUNXIANG ZHANG HONGEN LIAO XIN LIU DEAN TA academy for engineering and technology Fudan UniversityShanghai 200433China Center for Biomedical engineering Fudan UniversityShanghai 200433China Department of Chemistry Fudan UniversityShanghai 200433China Department of Biomedical engineering School of MedicineTsinghua UniversityBeijing 100084China

The COVID-19 pandemic continues to significantly impact people's lives worldwide, emphasizing the critical need for effective detection methods. Many existing deep learning-based approaches for COVID-19 detection offer high accuracy but demand substantial computing resources, time, and energy. In this study, we introduce an optical diffractive neural network(ODNN-COVID), which is characterized by low power consumption, efficient parallelization, and fast computing speed for COVID-19 detection. In addition, we explore how the physical parameters of ODNN-COVID affect its diagnostic performance. We identify the F number as a key parameter for evaluating the overall detection capabilities. Through an assessment of the connectivity of the diffractive network, we established an optimized range of F number, offering guidance for constructing optical diffractive neural networks. In the numerical simulations, a three-layer system achieves an impressive overall accuracy of 92.64% and 88.89% in binary-and threeclassification diagnostic tasks. For a single-layer system, the simulation accuracy of 84.17% and the experimental accuracy of 80.83% can be obtained with the same configuration for the binary-classification task, and the simulation accuracy is 80.19% and the experimental accuracy is 74.44% for the three-classification task. Both simulations and experiments validate that the proposed optical diffractive neural network serves as a passive optical processor for effective COVID-19 diagnosis, featuring low power consumption, high parallelization, and fast computing capabilities. Furthermore, ODNN-COVID exhibits versatility, making it adaptable to various image analysis and object classification tasks related to medical fields owing to its general architecture.

关键词： neural network offering

A Comprehensive Review on Mechanisms and Applications of Rare-Earth Based Perovskite Nanocrystals

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Chinese Journal of Chemistry 2024年第9期42卷 1032-1056页

作者： Xiaoshan Zhang Yikun Wang Xiang Wu Feilong Wang Qiongrong Ou Shuyu Zhang academy for engineering and technology Institute of Future LightingFudan UniversityShanghai 200433China School of Information Science and technology Institute for Electric Light SourcesFudan UniversityShanghai 200433China

Rare earth(RE)ions,with abundant 4f energy level and unique electronic arrangement,are considered as substitutes for Pb^(2+)in perovskite nanocrystals(PNCs),allowing for partial or complete replacement of lead and minimizing environmental *** review provides a comprehensive overview of the characteristics of RE-doped PNCs,including up-conversion luminescence,down-conversion luminescence,and quantum confinement effects,***,RE doping has been found to effectively suppress defect formation,reduce nonradiative recombination,enhance photoluminescence quantum yield(PLQY),and even allow for controlling over the morphology of the *** review also highlights the recent advancements in lead-free RE-based perovskites,especially in the case of Eu-based perovskites(CsEuBr_(3) and CsEuCl_(3)).Furthermore,it briefly introduces the applications of PNCs in various fields,such as perovskite solar cells(PSCs),luminescent solar concentrators(LSCs),photodetectors(PDs),and light-emitting diodes(LEDs).A systematic discussion on the luminescence mechanisms of RE-doped PNCs and lead-free RE-based perovskites is provided,along with an outlook on future research *** ultimate goal of this review is to provide guidance for the development of RE-based perovskite optoelectronic devices.

关键词： Perovskite nanocrystals Rare earth Lead-free perovskite lon doping Rare earth-based perovskite nanocrystals

Rational design of AgGaS/ZnS/ZnS quantum dots with a near-unity photoluminescence quantum yield via double shelling scheme

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Journal of Materials Science & technology 2024年第2期169卷 235-242页

作者： H.X.Lu H.Liu Z.Z.Fu Y.Y.Chen H.Q.Dai Z.Hu W.L.Zhang R.Q.Guo Institute for Electric Light Sources School of Information Science and TechnologyFudan UniversityShanghai 200433China Institute of Future Lighting Academy for Engineering and TechnologyFudan UniversityShanghai 200433China Yiwu Research Institute of fudan university YiwuZhejiang 322000China Zhongshan-fudan Joint Innovation Center Zhongshan 528437China

In this study,a two-step method was used to synthesize highly luminescent AgGaS/ZnS/ZnS quantum dots(QDs).In the first step,an inner ZnS shell was formed via a one-pot method,which resulted in a smaller lattice mismatch between the AgGaS core and the outer ZnS shell,thereby facilitating the formation of a thick outer *** the two-step shelling process,the synthesized AgGaS/ZnS/ZnS QDs showed an excellent photoluminescence quantum yield(PLQY)of 96.4%with a peak wavelength of 508 nm,repre-senting the highest PLQY reported thus far for AgGaS ***,the effect of halogen ions in Zn precursors on the shelling process was *** was proposed that the capacity of halogen ions to coordinate with the QDs influenced the balance between Zn cation diffusion and ZnS shelling ***,the ZnS shelling reaction was dominant when ZnCl_(2)was employed,while Zn cation diffusion was the dominant process under the I^(−)-rich *** work provides insights into the interfacial restructuring during the ZnS shelling and offers a clear map for the tailored synthesis of core/shell QDs.

关键词： AgGaS Quantum dots Photoluminescence Core/shell Alloyed core/shell interface

Channel estimation-based time-frequency neural network for post-equalization in underwater visible light communication

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Chinese Optics Letters 2024年第6期22卷 116-122页

作者： Haoyu Zhang Li Yao Chaoxu Chen Yuan Wei Chao Shen Jianyang Shi Junwen Zhang Ziwei Li Nan Chi Key Laboratory for Information Science of Electromagnetic Waves(MoE) Department of Communication Science and EngineeringSchool of Information Science and TechnologyFudan UniversityShanghai 200433China shanghai CIC of LEO Satellite Communication technology Fudan UniversityShanghai 200433China shanghai ERC of LEO Satellite Communication and Application Fudan UniversityShanghai 200433China

This Letter proposes a post-equalizer for underwater visible light communication(UVLC) systems that combines channel estimation and joint time-frequency analysis, named channel-estimation-based bandpass variable-order time-frequency network(CBV-TFNet). By utilizing a bandpass variable-order loss function with communication prior knowledge, CBVTFNet enhances communication performance and training stability. It enables lightweight implementation and faster convergence through a channel estimation-based mask. The superior performance of the proposed equalization method over Volterra and deep neural network(DNN)-based methods has been studied experimentally. Using bit-power loading discrete multitone (DMT) modulation, the proposed method achieves a transmission bitrate of 4.956 Gbps through a 1.2 m underwater channel utilizing only 38.15% of real multiplication calculations compared to the DNN equalizer and achieving a bitrate gain of440 Mbps and a significantly larger dynamic range over the LMS-Volterra equalizer. Results highlight CBV-TFNet's potential for future post-equalization in UVLC systems.

关键词： underwater visible light communication channel estimation post-equalizer neural network

Research on Bast Fiber Extracted from the White Bark of Three Species in the Genus Broussonetia

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Chinese Journal of Polymer Science 2024年第6期42卷 729-738页

作者： Shan-Shan Jin Si-Nong Wang Yan-Yan Huang Jing-Yu Zhang Peng Liu Hui Yu Hong-Dong Zhang Yu-Liang Yang Institute for Preservation and Conservation of Chinese Ancient Books Fudan University LibraryFudan UniversityShanghai200433China State key laboratory of Molecular engineering of polymers Department of Macromolecular ScienceFudan UniversityShanghai200433China

Against the backdrop of a global paper resource shortage,there is a growing need to identify fast-growing tree species capable of producing long-lasting *** plant species namely Broussonetia kazinoki,Broussonetia papyrifera and hybrid paper mulberry,belong to the Broussonetia genus,were collected from China to study their white bark suitability for pulp and *** chemical composition revealed that the holocellulose content in Broussonetia kazinoki and Broussonetia papyrifera was more than 80%.The molecular weight distribution of several holocellulose/α-cellulose is observed by GPC,which allows us to better observe the changes of various components on the molecular *** yield,lignin,whiteness,and molecular weight of the pulps obtained by NaOH treatment were *** microscope was used to characterize the fiber length-width ratio and ***,the improvement of the fiber rigidity method based on the Kratky-Porod chain model makes it more theoretical and further reveals the influencing factors of fiber *** study demonstrates the high potentiality of these three species for papermaking applications.

关键词： Broussonetia genus Cellulose Alkaline pulping Kratky-Porod chain model Fiber rigidity

Prompt learning in computer vision: a survey

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Frontiers of Information technology & Electronic engineering 2024年第1期25卷 42-63页

作者： Yiming LEI Jingqi LI Zilong LI Yuan CAO Hongming SHAN shanghai Key Laboratory of Intelligent Information Processing School of Computer ScienceFudan UniversityShanghai 200438China Institute of Science and technology for Brain-Inspired Intelligence Fudan UniversityShanghai 200433China MOE Frontiers Center for Brain Science Fudan UniversityShanghai 200433China shanghai Center for Brain Science and Brain-Inspired technology Shanghai 201210China

Prompt learning has attracted broad attention in computer vision since the large pre-trained visionlanguagemodels (VLMs) exploded. Based on the close relationship between vision and language information builtby VLM, prompt learning becomes a crucial technique in many important applications such as artificial intelligencegenerated content (AIGC). In this survey, we provide a progressive and comprehensive review of visual promptlearning as related to AIGC. We begin by introducing VLM, the foundation of visual prompt learning. Then, wereview the vision prompt learning methods and prompt-guided generative models, and discuss how to improve theefficiency of adapting AIGC models to specific downstream tasks. Finally, we provide some promising researchdirections concerning prompt learning.

关键词： Prompt learning Visual prompt tuning(VPT) Image generation Image classification Artificial intelligence generated content(AIGC)

Antisymmetric planar Hall effect in rutile oxide ﬁlms induced by the Lorentz force

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Science Bulletin 2024年第15期69卷 2362-2369页

作者： Yongwei Cui Zhaoqing Li Haoran Chen Yunzhuo Wu Yue Chen Ke Pei Tong Wu Nian Xie Renchao Che Xuepeng Qiu Yi Liu Zhe Yuan Yizheng Wu Department of Physics State Key Laboratory of Surface PhysicsFudan UniversityShanghai 200433China Institute for Nanoelectronic Devices and Quantum Computing Fudan UniversityShanghai 200433China Interdisciplinary Center for Theoretical Physics and Information Sciences Fudan UniversityShanghai 200433China Center for Advanced Quantum Studies and Department of Physics Beijing Normal UniversityBeijing 100875China Laboratory of Advanced Materials Shanghai Key Lab of Molecular Catalysis and Innovative MaterialsAcademy for Engineering&TechnologyFudan UniversityShanghai 200438China shanghai Key Laboratory of Special Artiﬁcial Microstructure Materials and technology School of Physics Science and EngineeringTongji UniversityShanghai 200092China Zhejiang Laboratory Hangzhou 311100China shanghai Research Center for Quantum Sciences Shanghai 201315China shanghai Key Laboratory of Metasurfaces for Light Manipulation Fudan UniversityShanghai 200433China

The conventional Hall effect is linearly proportional to the field component or magnetization component perpendicular to a film. Despite the increasing theoretical proposals on the Hall effect to the in-plane field or magnetization in various special systems induced by the Berry curvature, such an unconventional Hall effect has only been experimentally reported in Weyl semimetals and in a heterodimensional superlattice. Here, we report an unambiguous experimental observation of the antisymmetric planar Hall effect(APHE) with respect to the in-plane magnetic field in centrosymmetric rutile RuO_(2) and IrO_(2) single-crystal films. The measured Hall resistivity is found to be linearly proportional to the component of the applied in-plane magnetic field along a particular crystal axis and to be independent of the current direction or temperature. Both the experimental observations and theoretical calculations confirm that the APHE in rutile oxide films is induced by the Lorentz force. Our findings can be generalized to ferromagnetic materials for the discovery of anomalous Hall effects and quantum anomalous Hall effects induced by in-plane magnetization. In addition to significantly expanding knowledge of the Hall effect, this work opens the door to explore new members in the Hall effect family.

关键词： Antisymmetric planar Hall effect Lorentz force Rutile oxide films Crystal symmetry

Numerical Study on Comparison of Negative and Positive Surface Discharge in c-C_(4)F_(8)/CF_(3)I/CO_(2) Gas Mixture

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Journal of shanghai Jiaotong university(Science) 2024年第2期29卷 202-215页

作者：范彬海周小丽钱勇臧奕茗 academy for engineering&technology Fudan UniversityShanghai 200433China Department of Light Sources and Iluminating engineering School of Information Science and TechnologyFudan UniversityShanghai 200433China Department of Electronic engineering Shanghai Jiao Tong UniversityShanghai 200240China

The dynamics of negative surface discharges in c-C_(4)F_(8)/CF_(3)I/CO_(2) gas mixture is investigated here with a 2D fuid *** distributions of ion concentration,electric field strength and photon flux during the propagation of the streamer are obtained by solving the drift-diffusion equations of particles and Poisson's equation,and the photon flux variation function during the propagation is also *** is found that the streamer branches occur when the streamer transitions from the upper surface of the insulator to the side surface,and then when the streamer approaches the plane electrode,the photon flux will increase *** this basis,the positive and negative surface discharge models are compared in terms of streamer characteristics,particle characteristics and streamer *** is found that the streamer has a higher electron concentration and electric field in the positive *** streamer develops“floating”in the positive surface discharge,while it is close to the surface of the insulator in the negative *** addition,the negative streamer branch has a wider width and develops further.

关键词： streamer branch surface discharge c-C_(4)F_(8)/CF_(3)I/CO_(2)gas mixture positive and negative models

Recent progress on rapid diagnosis of COVID-19 by point-of-care testing platforms

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Chinese Chemical Letters 2024年第3期35卷 66-75页

作者： Ya-Nan Tang Dingding Jiang Xuejun Wang Yunqi Liu Dacheng Wei State Key Laboratory of Molecular engineering of Polymers Department of Macromolecular ScienceFudan UniversityShanghai 200433China Institute of Molecular Materials and Devices Fudan UniversityShanghai 200433China

The outbreak of COVID-19 has drawn great attention around the ***-CoV-2 is a highly infectious virus with occult transmission by many mutations and a long incubation *** particular,the emergence of asymptomatic infections has made the epidemic even more ***,early diagnosis and timely management of suspected cases are essential measures to control the spread of the *** simple,portable,and accurate diagnostic techniques for SARS-CoV-2 is the key to epidemic *** advantages of point-of-care testing technology make it play an increasingly important role in viral detection and *** review summarizes the point-of-care testing platforms developed by nucleic acid detection,immunological detection,and nanomaterial-based biosensors ***,this paper provides a prospect for designing future highly accurate,cheap,and convenient SARS-CoV-2 diagnostic technology.

关键词： COVID-19 Point-of-care testing platforms Nucleic acid detection Asymptomatic infection Biosensors