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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

Poly(3-hexylthio) thiophene Field-effect Transistor Device Performance: Impact of the Content of Hexylthio Side Chain on Backbone

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Chinese Journal of Polymer science 2024年第1期42卷 14-23,I0005页

作者： Hao-Yu Liu Lian-He Han Ling-Wei Kong Li-Ping Zhu Xiao-Lan Qiao Mei-Fang Zhu State Key Laboratory for Modification of Chemical Fibers and Polymer Materials College of Materials Science and EngineeringDonghua UniversityShanghai 201620China School of Electronic Information and Electrical Engineering Shanghai Jiao Tong UniversityShanghai 200240China

Regioregular poly(3-hexylthio)thiopene(P3HTT) has emerged tremendous potential in organic electronic applications due to the strong noncovalent interactions from the sulfur atom linked to thiophene. However, P3HTT generally exhibits low charge mobility mostly due to poor solution processability attributed to dense arrangement of hexylthio side chain in polymer, which led to strong noncovalent interactions among sulfur atoms. To balance the nonvalent interaction and aggregation for P3HTT, herein, we systematically study the effect of hexylthio side chain content in polymer backbone on the structure and properties. A series of regioregular P3HTT-based homopolymers(P3HTT, P3HTT-50,P3HTT-33 and P3HTT-25) were prepared via Kumada catalyst transfer polycondensation method from a set of mono-, bi-, ter-and quarterthiophenes containing different contents of hexylthio side chain. The DFT calculation shows the planarity of polymers backbone could be improved through reducing the density of hexylthio side chain in polymer mainchain. And significant changes in their crystallinity, aggregation and optical properties were observed with the content of hexylthio side chain reducing. The P3HTT-33 displayed the highest field-effect transistor hole mobility of 2.83×10^(-2) cm^(2)·V^(-1)·s^(-1) resulting from a balance between the crystallinity and planarity. This study demonstrates modulating the content of hexylthio side chain in P3HTT is an effective strategy to optimize the opto-electronic properties of polymer obtaining excellent semiconductor device performance.

关键词： Conjugated polymer Polythiophene Noncovalent interaction Molecular aggregation Organic field-effect transistor

Numerical simulation study on the hygrothermal performance of building exterior walls under dynamic wind-driven rain condition

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Building Simulation 2024年第2期17卷 207-221页

作者： Xing Hu Huibo Zhang Hui Yu School of Design Shanghai Jiao Tong UniversityShanghai200240China

Wind-driven rain(WDR)has a significant influence on the hygrothermal performance,durability,and energy consumption of building *** calculation of WDR loads using semi-empirical models has been incorporated into the boundary conditions of coupled heat and moisture transfer ***,prior research often relied on fixed WDR absorption ratio,which fail to accurately capture the water absorption characteristics of porous building materials under rainfall ***,this study aims to investigate the coupled heat and moisture transfer of exterior walls under dynamic WDR boundary conditions,utilizing an empirically obtained WDR absorption ratio model based on field *** developed coupled heat and moisture transfer model is validated against the HAMSTAD *** findings reveal that the total WDR flux calculated with the dynamic WDR boundary is lower than that obtained with the fixed WDR boundary,with greater disparities observed in orientations experiencing higher WDR *** variations in moisture flow significantly impact the surface temperature and relative humidity of the walls,influencing the calculation of cooling and heating loads by different *** to the transient heat transfer model,the coupled heat and moisture transfer model incorporating dynamic WDR boundary exhibits maximum increases of 17.6%and 16.2%in cooling and heating loads,*** dynamic WDR boundary conditions provide more precise numerical values for surface moisture flux,offering valuable insights for the thermal design of building enclosures and load calculations for HVAC systems.

关键词： wind-driven rain building component hygrothermal model transient simulation cooling and heating loads

Exploring luminescence quenching on lanthanide-doped nanoparticles through changing the spatial distribution of sensitizer and activator

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Nano Research 2024年第5期17卷 4517-4524页

作者： Jiwei Li Yao Xie Renrui Sun Junxun Zhou Lining Sun Department of Chemistry College of SciencesShanghai UniversityShanghai 200444China Department of Physics College of SciencesShanghai UniversityShanghai 200444China School of Medicine Shanghai UniversityShanghai 200444China

Luminescence quench is common in overdoped upconversion *** methods have been proposed to counteract the adverse effects of concentration quenching on luminescence,but in upconversion nanoparticles that are highly doped with both sensitizers and activators,the factors that contribute to the diminishing of the emission cannot be summarized by a single ***,a core-shell design is used to spatially separate the sensitizer(Yb^(3+))and activator(Er^(3+))and to modulate the emission by changes in the distribution position as well as the concentration of the dopant ions in order to probe the factors affecting the *** the sensitizer ions are located in the core,the luminescence intensity of the nanoparticles is significantly weaker than that of the other distribution,which implies that the effect of sensitizer and activator on luminescence in the highly doped state has a different and more complex *** intensity of the emission is more affected by Yb^(3+)than Er^(3+),which includes not only the self-quenching of Yb^(3+),but also the dominance in the Yb^(3+)-Er^(3+)*** this finding may provide new ideas for revealing the reasons for the diminished luminescence of highly doped upconversion nanoparticles and thus for enhancing luminescence.

关键词： upconversion luminescence lanthanide ion core-shell nanoparticles concentration quenching cross-relaxation

In-situ construction of PDOL electrolyte with dual-reinforced stable interface for high-voltage lithium metal batteries

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science China Chemistry 2024年第5期67卷 1664-1671页

作者： Yingkang Wu Yuzhou Bai Wujie Dong Xue Wang Wenqin Ma Fuqiang Huang State Key Lab of Metal Matrix Composites School of Materials Science and EngineeringShanghai Jiao Tong UniversityShanghai 200240China School of Physical science and Technology Shanghai Tech UniversityShanghai 201210China shanghai Institute of Ceramics Chinese Academy of SciencesShanghai 200050China

In-situ polymerized electrolytes significantly enhance the interfacial compatibility of lithium metal batteries(LMBs). Typically,in-situ polymerized 1,3-dioxolane(PDOL) exhibits low interfacial resistance, yet still suffers from low ionic conductivity and a narrow electrochemical stability window(ESW). Here, an ultra-stable PDOL-based polymer electrolyte is developed by incorporating plasticizers of tetramethylene sulfone(TMS) and fluorinated ethylene carbonate(FEC) into the 3D cross-linked network, achieving a significant enhancement in the transport capacity and efficiency of Li-ion. The ionic conductivity reaches3.63×10^(-4)S cm^(-1)even at room temperature, and the transference number(tLi^(+)) is even higher at 0.85. Furthermore, the ESW of this electrolyte can be increased to 4.5 V with the addition of TMS, which forms a thin and robust antioxidant cathode-electrolyte interface(CEI) on the surface of high-voltage LiCoO_(2). FEC generates an inorganic-rich solid-electrolyte interface(SEI) on the Li anode, which effectively inhibits the growth of lithium dendrites. Benefiting from the aforementioned advantages, the highvoltage lithium metal battery demonstrates outstanding long-cycle stability, with 93.2% capacity retention after 200 cycles. This work offers a straightforward and accessible method for the practical implementation of high energy density in-situ polymerized solid-state LMBs.

关键词： solid polymer electrolyte in-situ polymerization PDOL high-voltage LMBs

Demonstration of acousto-optical modulation based on a thin-film AlScN photonic platform

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Photonics Research 2024年第6期12卷 1138-1149页

作者： KEWEI BIAN ZHENYU LI YUSHUAI LIU SUMEI XU XINGYAN ZHAO YANG QIU YUAN DONG QIZE ZHONG TAO WU SHAONAN ZHENG TING HU School of Microelectronics Shanghai UniversityShanghai 201800China School of Information science and Technology ShanghaiTech UniversityShanghai 201210China shanghai Institute of Microsystem and Information Technology Chinese Academy of SciencesShanghai 200050China University of Chinese Academy of sciences Beijing 100049China

Acousto-optic(AO)modulation technology holds significant promise for applications in microwave and optical signal ***-film scandium-doped aluminum nitride(AlScN),with excellent piezoelectric properties and a wide transparency window,is a promising candidate for achieving on-chip AO modulation with a fabri-cation process compatible with complementary metal-oxide-semiconductor(CMOS)*** study presents,to the best of our knowledge,the first demonstration of AO modulators with surface acoustic wave generation and photonic waveguides monolithically integrated on a 400-nm-thick film of AlScN on an *** intramodal AO modulation is realized based on an AlScN straight waveguide,and the modulation efficiency is significantly enhanced by 12.3 dB through the extension of the AO interaction length and the utilization of bidirectional acoustic *** intermodal AO modulation and non-reciprocity are further demonstrated based on a multi-mode spiral waveguide,achieving a high non-reciprocal contrast(>10 dB)across an optical bandwidth of 0.48 *** research marks a significant stride forward,representing an advancement in the realization of microwave photonic filters,magnet-free isolators,and circulators based on the thin-film AlScN photonic platform.

关键词： waveguide film microwave

A Novel Scalable Fault-Tolerant Control Design for DC Microgrids With Nonuniform Faults

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IEEE/CAA Journal of Automatica Sinica 2024年第8期11卷 1886-1888页

作者： Aimin Wang Minrui Fei Dajun Du Yang Song shanghai Key Laboratory of Power Station Automation Technology the School of Mechatronic Engineering and AutomationShanghai UniversityShanghai 200072China

Dear Editor,The existing control schemes for microgrids(MGs)face challenges in effectively addressing plugging in/out operations under uncertain power lines and *** tackle this issue,this letter proposes a novel scalable fault-tolerant control(FTC)strategy for DC *** developing a structured Lyapunov matrix(SLM),a decoupled FTC method is introduced to mitigate the adverse effects of uncertain lines and nonuniform ***,global stability is ensured by deriving local rules expressed as linear matrix inequalities(LMIs)that solely depend on local *** new distributed generation unit(DGU)introduces only one additional condition of this nature,allowing the stability rules to scale with topology ***,the effectiveness of the proposed scheme is illustrated through simulations conducted using the MATLAB/SimPowerSystems toolbox.

关键词： stability letter operations

A novel complex-high-order graph convolutional network paradigm:ChyGCN

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Chinese Physics B 2024年第5期33卷 665-672页

作者：郑和翔苗书宇顾长贵 Business School University of Shanghai for Science and TechnologyShanghai 200093China Ant Group Shanghai 200000China

In recent years,there has been a growing interest in graph convolutional networks(GCN).However,existing GCN and variants are predominantly based on simple graph or hypergraph structures,which restricts their ability to handle complex data correlations in practical *** limitations stem from the difficulty in establishing multiple hierarchies and acquiring adaptive weights for each of *** address this issue,this paper introduces the latest concept of complex hypergraphs and constructs a versatile high-order multi-level data correlation *** model is realized by establishing a three-tier structure of ***,we start by establishing hyperedge clusters on a foundational network,utilizing a second-order hypergraph structure to depict potential *** this second-order structure,truncation methods are used to assess and generate a three-layer composite *** the construction of the composite structure,an adaptive learning strategy is implemented to merge correlations across different *** evaluate this model on several popular datasets and compare it with recent state-of-the-art *** comprehensive assessment results demonstrate that the proposed model surpasses the existing methods,particularly in modeling implicit data correlations(the classification accuracy of nodes on five public datasets Cora,Citeseer,Pubmed,Github Web ML,and Facebook are 86.1±0.33,79.2±0.35,83.1±0.46,83.8±0.23,and 80.1±0.37,respectively).This indicates that our approach possesses advantages in handling datasets with implicit multi-level structures.

关键词： raph convolutional network complex modeling complex hypergraph

Recent progress of self-supported air electrodes for flexible Zn-air batteries

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Journal of Energy Chemistry 2024年第2期89卷 110-136,I0004页

作者： Chen Xu Yanli Niu Vonika Ka-Man Au Shuaiqi Gong Xuan Liu Jianying Wang Deli Wu Zuofeng Chen School of Chemical science and Engineering Tongji UniversityShanghai 200092China College of Environmental science&Engineering Tongji UniversityShanghai 200092China Department of science and Environmental Studies The Education University of Hong KongHong KongChina

Smart wearable devices are regarded to be the next prevailing technology product after smartphones and smart homes,and thus there has recently been rapid development in flexible electronic energy storage *** them,flexible solid-state zinc-air batteries have received widespread attention because of their high energy density,good safety,and *** bifunctional oxygen electrocatalysts are the primary consideration in the development of flexible solid-state zinc-air batteries,and self-supported air cathodes are strong candidates because of their advantages including simplified fabrication process,reduced interfacial resistance,accelerated electron transfer,and good *** review outlines the research progress in the design and construction of nanoarray bifunctional oxygen *** from the configuration and basic principles of zinc-air batteries and the strategies for the design of bifunctional oxygen electrocatalysts,a detailed discussion of self-supported air cathodes on carbon and metal substrates and their uses in flexible zinc-air batteries will ***,the challenges and opportunities in the development of flexible zinc-air batteries will be discussed.

关键词： Bifunctional electrocatalysts Oxygen reduction reaction Oxygen evolution reaction Self-supported air electrodes Flexible zinc-air batteries