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Noninvasive interception of circulating leukocyte in vivo by optical tweezer array 被引量:1
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作者 Sisi Ge Jinhua Zhou Xunbin Wei 《Journal of Innovative Optical Health Sciences》 2026年第1期56-69,共14页
The ability to noninvasively manipulate and isolate specific cell populations in vivo is critical for advancing real-time diagnostics,precision medicine,and immunological research.Here,we present a novel and broadly a... The ability to noninvasively manipulate and isolate specific cell populations in vivo is critical for advancing real-time diagnostics,precision medicine,and immunological research.Here,we present a novel and broadly applicable optical trapping system based on a custom-designed 2×3 optical tweezer array,which enables the real-time interception and manipulation of circulating leukocytes in live animals.By utilizing intrinsic velocity differences between leukocytes and red blood cells,the system achieves stable trapping of individual leukocytes in vessels 15-20μm in diameter and decelerates multiple cells in vessels greater than 20μm.Notably,it also enables the optical blockage of lymphatic vessels exceeding 50μm,a previously unreported capability.This label-free,noninvasive approach operates without repeated blood draws and is compatible with diverse vessel geometries and flow dynamics.The system offers a generalizable solution for in vivo cell extraction and analysis,paving the way for high-precision single-cell technologies in biomedical research and clinical translation. 展开更多
关键词 Leukocytes optical tweezer array in vivo interception
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Deep learning-based number of sources estimation under colored noise and imperfect array
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作者 Linqiang JIANG Tao TANG +2 位作者 Zhidong WU Ding WANG Paihang ZHAO 《Chinese Journal of Aeronautics》 2026年第2期414-428,共15页
The estimation of the Number of Sources(NoS)is a significant challenge in signal processing,particularly due to the impact of colored noise on the performance of NoS estimation.This paper proposes a Multidimensional F... The estimation of the Number of Sources(NoS)is a significant challenge in signal processing,particularly due to the impact of colored noise on the performance of NoS estimation.This paper proposes a Multidimensional Feature Network(MFNet)which is designed for NoS estimation by extracting features of the sampled received signals and Sampled Covariance Matrix(SCM).The MFNet treats the raw signal and the SCM as two different types of data,and is able to achieve NoS estimation under colored noise and imperfect array.MFNet employs the Gated Recurrent Unit(GRU)to capture sequential information from the original signal data and to construct the Pseudo Covariance Matrix(PCM).Subsequently,various dimensional features,including eigenvalues and the Gerschgorin disk radius,are extracted from both the PCM and SCM,which are then jointly input into the subsequent network.An overall accuracy of 82%can be achieved after network training.The ablation experimental results demonstrate the effectiveness of multiple inputs.And simulation results demonstrate that the proposed MFNet achieves higher estimation accuracy compared to existing algorithms and exhibits greater robustness against colored noise. 展开更多
关键词 Number of source estimation Deep learning Colored noise Imperfect array array signal processing
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A new 10K liquid SNP genotyping array for wax gourd and its application in heterosis utilization and cultivars identification
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作者 Dan Liu Lingling Xie +4 位作者 Yuting Lei Bingchuan Tian Daolong Liao Fangfang Wu Baobin Mi 《Journal of Integrative Agriculture》 2026年第2期734-743,共10页
High-throughput single nucleotide polymorphism(SNP) arrays have emerged as essential genotyping tools,significantly accelerating breeding programs and advancing basic research.In this study,a high-throughput 10K SNP g... High-throughput single nucleotide polymorphism(SNP) arrays have emerged as essential genotyping tools,significantly accelerating breeding programs and advancing basic research.In this study,a high-throughput 10K SNP genotyping array for wax gourd was developed using genotyping by target sequencing(GBTS),featuring 10,722 SNPs evenly distributed across all 12 chromosomes,including 278 functional loci associated with key economic traits.To demonstrate its utility,genetic distances among 19 elite inbred lines were calculated from SNP data and correlated with heterosis for single fruit weight.The results revealed that greater genetic distance was associated with higher middle parent heterosis(MPH) for single fruit weight.Furthermore,56 commercial wax gourd cultivars collected from eight regions were selected and genotyped.Population structure analysis,phylogenetic analysis,and principal component analysis(PCA) collectively indicated that these cultivars fall into two major groups.Group I,comprising black or dark green skinned wax gourds,exhibited lower genetic diversity than Group II,which includes green or light green skinned varieties,reflecting shorter genetic distances within Group I.Finally,60 polymorphic SNPs were used to construct DNA fingerprints for distinguishing the 56 cultivars.As the first high-throughput genotyping platform for wax gourd,this SNP array provides an effective and powerful tool for genetic analysis. 展开更多
关键词 wax gourd SNP genotyping array HETEROSIS cultivar identification DNA fingerprint
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Cellular behavior regulation and adhesion force measurement based on flexible micropillar arrays
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作者 Ruoyu Feng Hang Qi +1 位作者 Xuexin Duan Yanyan Wang 《Nanotechnology and Precision Engineering》 2026年第1期34-43,共10页
Systematic understanding of the interaction between cells and their microenvironment is of wide interest.To investigate this interaction,a flexible micropillar array device integrating dual functions of cell behavior ... Systematic understanding of the interaction between cells and their microenvironment is of wide interest.To investigate this interaction,a flexible micropillar array device integrating dual functions of cell behavior regulation and adhesion measurement is developed.Micropillar arrays with high and low densities are designed to explore the role of substrate topography in the behavior of human bone marrow mesenchymal stem cells.In addition,a method is established for quantifying weak cell adhesion forces on the basis of micropillar deflections.The results show that cell cytoplasmic adhesion is greater on a low-density micropillar array than that on a high-density array and is localized mainly in the perinuclear region of the cytoplasm rather than in pseudopods.It is also found that the micropillar array topography facilitates the oriented spreading of cell morphology and pseudopod formation,and a reduction in focal adhesion aggregation and F-actin polarization compared with a flat substrate.Notably,cells cultured on a low-density micropillar array exhibited a higher number of pseudopods,stronger adhesion forces,and greater stiffness compared with those on a high-density array.In summary,this work employs an adhesion force sensor,immunofluorescence staining,and atomic force microscopy to investigate the mechanical properties of cells and elucidate the mechanisms by which micropillar topographical cues regulate the adhesion of mesenchymal stem cells to the substrate.The micropillar array force sensor developed in this study provides an effective tool for simultaneously modulating cell behavior and quantifying adhesion forces,offering valuable insights for biomechanical research. 展开更多
关键词 Micropillar array Mesenchymal stem cell Cell mechanics Adhesion force
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A Reconfigurable Omnidirectional Triboelectric Whisker Sensor Array for Versatile Human–Machine–Environment Interaction
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作者 Weichen Wang Jiaqi Zhu +9 位作者 Hongfa Zhao Fei Yao Yuzhu Zhang Xiankuan Qian Mingrui Shu Zhigang Wu Minyi Xu Hongya Geng Wenbo Ding Juntian Qu 《Nano-Micro Letters》 2026年第3期121-140,共20页
Developing effective,versatile,and high-precision sensing interfaces remains a crucial challenge in human-machine-environment interaction applications.Despite progress in interaction-oriented sensing skins,limitations... Developing effective,versatile,and high-precision sensing interfaces remains a crucial challenge in human-machine-environment interaction applications.Despite progress in interaction-oriented sensing skins,limitations remain in unit-level reconfiguration,multiaxial force and motion sensing,and robust operation across dynamically changing or irregular surfaces.Herein,we develop a reconfigurable omnidirectional triboelectric whisker sensor array(RO-TWSA)comprising multiple sensing units that integrate a triboelectric whisker structure(TWS)with an untethered hydro-sealing vacuum sucker(UHSVS),enabling reversibly portable deployment and omnidirectional perception across diverse surfaces.Using a simple dual-triangular electrode layout paired with MXene/silicone nanocomposite dielectric layer,the sensor unit achieves precise omnidirectional force and motion sensing with a detection threshold as low as 0.024 N and an angular resolution of 5°,while the UHSVS provides reliable and reversible multi-surface anchoring for the sensor units by involving a newly designed hydrogel combining high mechanical robustness and superior water absorption.Extensive experiments demonstrate the effectiveness of RO-TWSA across various interactive scenarios,including teleoperation,tactile diagnostics,and robotic autonomous exploration.Overall,RO-TWSA presents a versatile and high-resolution tactile interface,offering new avenues for intelligent perception and interaction in complex real-world environments. 展开更多
关键词 Reconfigurable sensor array Interaction interface Tactile perception Omnidirectional sensor Reversible anchoring
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Design and investigation of iontronic flexible pressure sensor based on microstructure array
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作者 Zhenzhen Shang Hairong Kou +2 位作者 Libo Yang Xiaoyong Zhang Yuhang Pang 《Nanotechnology and Precision Engineering》 2026年第1期44-51,共8页
Flexible pressure sensors are widely used in fields such as healthcare,owing to their simple preparation method,abundant raw materials,and high sensitivity.To solve the problems of low sensitivity and high noise impac... Flexible pressure sensors are widely used in fields such as healthcare,owing to their simple preparation method,abundant raw materials,and high sensitivity.To solve the problems of low sensitivity and high noise impact that arise with traditional capacitive pressure sensors,this paper proposes an electrical double layer microarray capacitive pressure sensor using silver nanowires(AgNW)and ionic liquids.AgNW/polyimide(PI)flexible electrodes and microarray-structured ionic liquids are utilized to obtain highly sensitive responses to changes in weak physiological signals.The microarray structure is a 20×20 quadrangular prism convex array.Experimental tests show that the sensor has high sensitivity(3.1202 kPa^(−1),0–800 kPa)and fast response/recovery times(100/100 ms).By flexibly attaching the sensor to the skin or a computer mouse,rapid and stable monitoring of micromovements such as facial muscles,vocalization,swallowing,finger joint activity,and mouse clicks can be achieved.The results obtained here are of value for the development of intelligent flexible electronics. 展开更多
关键词 Electronic skin Iontronic mechanism Flexible sensor Ionic dielectric layer Highly sensitive array
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Adaptive implementation of multi-branch convolution with fusion coefficients based on reconfigurable array
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作者 Liu Dongyue Jiang Lin +2 位作者 Wang Mei Li Yuancheng Hao Juan 《High Technology Letters》 2026年第1期39-48,共10页
Reconfigurable array architecture has become an important hardware platform for edge-side deployment of convolutional neural networks due to their high parallelism and flexible programmability.However,traditional mult... Reconfigurable array architecture has become an important hardware platform for edge-side deployment of convolutional neural networks due to their high parallelism and flexible programmability.However,traditional multi-branch convolutional networks suffer from computational redundancy,high memory access overhead,and inefficient branch fusion.Therefore,this paper proposes an adaptive multi-branch convolutional module(AMBC)that integrates software-hardware co-optimization.During training,the learnable fusion coefficients are introduced to enable adaptive fusion of multi-scale features,while in the inference phase,the multiple branches and their normalization parameters are merged with the fusion coefficients into a single 3×3 convolutional kernel through operator fusion.On the SIREA-288 reconfigurable platform,compared with unoptimized multi-branch networks,the proposed AMBC reduces external memory accesses by 47.91%and inference latency by 47.20%,achieving a 1.90×speedup.This approach maximizes the utilization of the reconfigurable logic while minimizing both reconfiguration and data-movement overheads in edge inference. 展开更多
关键词 reconfigurable array processor structural re-parameterization model compression fusion coefficients edge-side inference acceleration hardware-software co-optimization
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Bio-inspired offset array design for enhanced range in underwater active electrosensing with neural network-based localization
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作者 Meijiang Hou Jiegang Peng +2 位作者 Minan Yang Taoyu Jiang Yang Chen 《Defence Technology(防务技术)》 2026年第3期217-245,共29页
Addressing the critical detection range limitation in active electrosensing(AES)for underwater sensing,this study proposes an enhanced AES system via novel array optimization.While AES offers advantages like interfere... Addressing the critical detection range limitation in active electrosensing(AES)for underwater sensing,this study proposes an enhanced AES system via novel array optimization.While AES offers advantages like interference immunity,acoustic stealth detection,and low cost,its short range restricts applicability.A target perturbation model under differential signal acquisition reveals that signal strength increases with local electric field intensity,target size,differential channel spacing,and conductivity contrast,but decreases with target-electrode distance.To extend detection,novel array configurations were explored.Simulations demonstrate that both rectangular and offset arrays significantly outperform the traditional collinear layout.Specifically,an offset array(with 8 m transmitting–receiving spacing)achieved an effective detection range enhancement exceeding 83%under the same distortion threshold while maintaining simplified electrode structure.Experimental validation confirmed a 100%increase in maximum detection distance to 5 m under identical noise thresholds compared to the collinear array.Furthermore,a fully connected neural network-based localization model achieved a mean positioning error of 14.12 cm at 3.15 m in static scenarios.In dynamic scenarios within 1–3 m,mean errors were controlled between 13.19 cm and 27.56 cm.Mechanistic analysis indicates that increasing the array baseline enhances the signal-to-noise ratio by simultaneously suppressing near-field environmental noise and amplifying far-field signal reception.Structural innovations in array design enabled this study to significantly expand the detection range of AES systems without compromising cost efficiency.These advancements directly promote the engineering application of AES technology,offering critical technical support for underwater defense security monitoring,long-range early warning systems,and maritime rights protection. 展开更多
关键词 Active electrical sensing Target perturbation model array optimization Detection range Fuly connected neural network
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3D printed high-temperature ceramic conformal array antenna:Design,analysis,manufacturing,and testing
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作者 Peng Li Ruibo Li +5 位作者 Zijiao Fan Jiujiu Han Guangda Ding Qunbiao Wang Wanye Xu Paolo Rocca 《Defence Technology(防务技术)》 2026年第1期340-353,共14页
In this study,the design,analysis,manufacturing,and testing of a 3D-printed conformal microstrip array antenna for high-temperature environments is presented.3D printing technology is used to fabricate a curved cerami... In this study,the design,analysis,manufacturing,and testing of a 3D-printed conformal microstrip array antenna for high-temperature environments is presented.3D printing technology is used to fabricate a curved ceramic substrate,and laser sintering and microdroplet spraying processes are used to add the conductive metal on the curved substrate.The problems of gain loss,bandwidth reduction,and frequency shift caused by high temperatures are addressed by using a proper antenna design,with parasitic patches,slots,and metal resonant cavities.The antenna prototype is characterized by the curved substrates and the conductive metals for the power dividers,the patch,and the ground plane;its performance is examined up to a temperature of 600℃in a muffle furnace and compared with the results from the numerical analysis.The results show that the antenna can effectively function at 600℃and even higher temperatures. 展开更多
关键词 Ceramic antenna Conformal array High-temperature environment 3D printing High gain and wide band
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Short-period dense linear array ambient noise tomography of shallow crustal structure across the Haichenghe fault zone,China
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作者 Mingruo Jiao Liang Wang +9 位作者 Hongyu Ni Haiyan Wang Lanshu Bai Shuo Liu Zhihong Zhang Zhenpeng Yang Zhengdong Cui Qingshan Sun Rui Qian Mengying Li 《Earthquake Science》 2026年第2期220-234,共15页
The Haicheng region,Liaoning,China,likely hosts a conjugate fault system comprising the NW-trending Haichenghe fault and NE-trending secondary faults.On February 4,1975,at 19:36 CST,an earthquake of M_(S)7.3 and inten... The Haicheng region,Liaoning,China,likely hosts a conjugate fault system comprising the NW-trending Haichenghe fault and NE-trending secondary faults.On February 4,1975,at 19:36 CST,an earthquake of M_(S)7.3 and intensity(MMI)IX hit the city of Haicheng,Liaoning,China.Although deep seismic profiling was previously conducted along the Haichenghe fault,the limited horizontal resolution in the shallow part prevented the recognition of kilometer-scale anomalies.The velocity structure characteristics of the Haichenghe fault and its NE-trending conjugate faults remain unclear.Using the extended range phase shift method,the high-resolution S-wave velocity structures are obtained by deploying a long,dense linear array of 55 short-period seismometers across the fault and NE-trending conjugate faults.The array length was 32 km and inter-station spacing was approximately 600 m,facilitating the collection of approximately 22 days of continuous waveform data.Employing the Extended Range Phase Shift(ERPS)method enabled the extraction of broadband 0.2–5 s Rayleigh wave phase velocity dispersion curves.The broadband dispersion data were used for inversion of the high-resolution S-wave velocity structure to a depth of 8 km from the surface.The velocity structure characteristics and seismicity of the Haichenghe fault and NE-trending conjugate faults were analyzed and compared with nearby fault gas measurements.Results show(1)shallow S-wave velocities show a low-high-low horizontal distribution,corresponding to basin-uplift-basin topography;(2)significant velocity contrasts occur across the Haichenghe fault:its SW segment(0–17 km)exhibits high velocities consistent with Paleoproterozoic crystalline basement(Pt_(1)),while the NE segment(17–32 km)shows low velocities related to Yanshanian intrusions(γ_(5))and Quaternary sediments.NE-trending conjugate faults display sharp velocity gradients marking fracture locations,with all faults being near-vertical to~8 km depth;(3)seismicity at 1–6 km depth mainly clusters in high-velocity zones;at 6–8 km depth,it concentrates beneath the Haichenghe fault in low-velocity areas and along NE-trending faults;(4)the seismic activity characteristics and fault zone width of the Haicheng he fault reflected by velocity imaging results are basically consistent with those obtained by the fault gas measurement method. 展开更多
关键词 dense linear array ambient noise tomography extended range phase shift method S-wave velocity structure Haichenghe fault
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Structural Color Dynamic Graphics Display Based on Microlens Array 被引量:1
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作者 LI Xue-han LIU Ling-zhi +1 位作者 HUANG Min LI Xiu 《印刷与数字媒体技术研究》 北大核心 2025年第2期162-168,共7页
It is of great scientific significance to construct a 3D dynamic structural color with a special color effect based on the microlens array.However,the problems of imperfect mechanisms and poor color quality need to be... It is of great scientific significance to construct a 3D dynamic structural color with a special color effect based on the microlens array.However,the problems of imperfect mechanisms and poor color quality need to be solved.A method of 3D structural color turning on periodic metasurfaces fabricated by the microlens array and self-assembly technology was proposed in this study.In the experiment,Polydimethylsiloxane(PDMS)flexible film was used as a substrate,and SiO2 microspheres were scraped into grooves of the PDMS film to form 3D photonic crystal structures.By adjusting the number of blade-coated times and microsphere concentrations,high-saturation structural color micropatterns were obtained.These films were then matched with microlens arrays to produce dynamic graphics with iridescent effects.The results showed that by blade-coated two times and SiO2 microsphere concentrations of 50%are the best conditions.This method demonstrates the potential for being widely applied in the anticounterfeiting printing and ultra-high-resolution display. 展开更多
关键词 Structural color Microlens array Dynamic graphics display Moirémagnification Optical anti-counterfeiting
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Improving DOA estimation of GNSS interference through sparse non-uniform array reconfiguration 被引量:3
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作者 Rongling LANG Hao XU +3 位作者 Fei GAO Zewen TANG Zhipeng WANG Amir HUSSAIN 《Chinese Journal of Aeronautics》 2025年第8期104-118,共15页
Interference significantly impacts the performance of the Global Navigation Satellite Systems(GNSS),highlighting the need for advanced interference localization technology to bolster anti-interference and defense capa... Interference significantly impacts the performance of the Global Navigation Satellite Systems(GNSS),highlighting the need for advanced interference localization technology to bolster anti-interference and defense capabilities.The Uniform Circular Array(UCA)enables concurrent estimation of the Direction of Arrival(DOA)in both azimuth and elevation.Given the paramount importance of stability and real-time performance in interference localization,this work proposes an innovative approach to reduce the complexity and increase the robustness of the DOA estimation.The proposed method reduces computational complexity by selecting a reduced number of array elements to reconstruct a non-uniform sparse array from a UCA.To ensure DOA estimation accuracy,minimizing the Cramér-Rao Bound(CRB)is the objective,and the Spatial Correlation Coefficient(SCC)is incorporated as a constraint to mitigate side-lobe.The optimization model is a quadratic fractional model,which is solved by Semi-Definite Relaxation(SDR).When the array has perturbations,the mathematical expressions for CRB and SCC are re-derived to enhance the robustness of the reconstructed array.Simulation and hardware experiments validate the effectiveness of the proposed method in estimating interference DOA,showing high robustness and reductions in hardware and computational costs associated with DOA estimation. 展开更多
关键词 GNSS interference location Direction of arrival estimation Adaptive reconfigurable array Cramér-Raobound Quadratic fractional programming
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Confronting pressure and humidity limitations in gold nanoparticle sensors array for enhancing electronic nose technology in real-world applications 被引量:1
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作者 Xue Jiang Dan-Yao Qu +11 位作者 Jun-Nan Zhang Viki Kloper Ke-Fan Zhang Guang-Jian Zhang Lei Wang Ming-Hu Pan Quan-Min Guo Li Chen Wei-Tian Huang Jian-Zhi Gao Hossam Haick Wei-Wei Wu 《Rare Metals》 2025年第11期8789-8801,共13页
The field of disease smelling diagnosis has experienced a major breakthrough with the development of the electronic nose(E-nose)that utilizes thiol-capped gold nanoparticles(GNPs).This study focuses on overcoming the ... The field of disease smelling diagnosis has experienced a major breakthrough with the development of the electronic nose(E-nose)that utilizes thiol-capped gold nanoparticles(GNPs).This study focuses on overcoming the challenges of sensors to detect VOCs stably confounding with interferents of humidity and pressure,and clarifying their essential mechanism.An innovative and straightforward method for synthesizing GNPs and modifying their surface has been developed.This unique approach deviates from the conventional Brust method by completely removing any traces of tetraoctylammonium bromide(TOAB),ensuring reproducibility and simplicity of use.This modification enhances the sensor's responsiveness to both polar and non-polar VOCs,as well as strengthen selectivity and anti-interferant capabilities.The mechanism of generating sensing cross-talk from TOAB residue is proposed through rigorous sensing experiments,X-ray photoelectron spectroscopy(XPS)results,and theoretical analysis.Thus,this study enhances the responsiveness of the sensor to both polar and non-polar VOCs,while also strengthening its selectivity and anti-interferent capabilities.This could potentially revolutionize the practical applications of E-nose in smelling diagnosis. 展开更多
关键词 Gold nanoparticles Volatile organic compounds Gas sensor Humidity insensitive Sensors array
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Integrated Optical True Time Delay Phased Array Antenna Systems 被引量:1
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作者 Qi Zihang Yang Linhui +1 位作者 Zhao Wenyu Li Xiuping 《China Communications》 2025年第5期152-172,共21页
The integrated optical true time delay phased array antenna system has the advantages of high bandwidth,small size,low loss and strong antiinterference capability,etc.The high integration of the optically controlled p... The integrated optical true time delay phased array antenna system has the advantages of high bandwidth,small size,low loss and strong antiinterference capability,etc.The high integration of the optically controlled phased array antenna system is a necessary trend for the future development of the phased array,and it is also a major focus and difficulty in the current research of integrated microwave photonics.This paper firstly introduces the basic principle and development history of optical true time delay phased array antenna system based on microwave photonics,and briefly introduces the main implementation methods and integration platform of optical true time delay.Then,the application and development prospect of optical true time delay technology in beam control of phased array antenna system are mainly presented.Finally,according to the current research progress,the possible research directions of integrated optically controlled phased array antenna systems in the future are proposed. 展开更多
关键词 microwave photonics optical switch optical true time delay phased array antenna siliconbased integration
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Low-profile,low sidelobe array antenna with ultrawide beam coverage for UAV communication 被引量:1
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作者 Mei LI Zhiliang SHANG +2 位作者 Lin PU Ming-Chun TANG Lei ZHU 《Chinese Journal of Aeronautics》 2025年第1期444-454,共11页
This paper presents a design method to implement an antenna array characterized by ultra-wide beam coverage,low profile,and low Sidelobe Level(SLL)for the application of Unmanned Aerial Vehicle(UAV)air-to-ground commu... This paper presents a design method to implement an antenna array characterized by ultra-wide beam coverage,low profile,and low Sidelobe Level(SLL)for the application of Unmanned Aerial Vehicle(UAV)air-to-ground communication.The array consists of ten broadside-radiating,ultrawide-beamwidth elements that are cascaded by a central-symmetry series-fed network with tapered currents following Dolph-Chebyshev distribution to provide low SLL.First,an innovative design of end-fire Huygens source antenna that is compatible with metal ground is presented.A low-profile,half-mode Microstrip Patch Antenna(MPA)is utilized to serve as the magnetic dipole and a monopole is utilized to serves as the electric dipole,constructing the compact,end-fire,grounded Huygens source antenna.Then,two opposite-oriented end-fire Huygens source antennas are seamlessly integrated into a single antenna element in the form of monopole-loaded MPA to accomplish the ultrawide,broadside-radiating beam.Particular consideration has been applied into the design of series-fed network as well as antenna element to compensate the adverse coupling effects between elements on the radiation performance.Experiment indicates an ultrawide Half-Power Beamwidth(HPBW)of 161°and a low SLL of-25 dB with a high gain of 12 d Bi under a single-layer configuration.The concurrent ultrawide beamwidth and low SLL make it particularly attractive for applications of UAV air-to-ground communication. 展开更多
关键词 array antenna Broad beam Fan beam Low sidelobe level Chebyshev synthesis UAV communication
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Arbitrary azimuthal optical field manipulation by dual-spiral arrays
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作者 MA Li WANG Ying +2 位作者 LI Min ZHANG Ying ZHAO Bo 《中国光学(中英文)》 北大核心 2025年第4期921-930,共10页
Optical field manipulation,an emerging frontier in photonics,demonstrates significant potential in biomedical microscopy,quantum state engineering,and micro-nano fabrication.To address the critical limitations of curr... Optical field manipulation,an emerging frontier in photonics,demonstrates significant potential in biomedical microscopy,quantum state engineering,and micro-nano fabrication.To address the critical limitations of current optical modulation technologies in achieving full-parameter precision control,we proposed a novel approach for dynamic azimuthal optical field modulation based on dual-spiral arrays.By designing spatially interleaved spiral structures with different initial radii while maintaining identical periodic parameters,we achieved continuous optical modulation spanning the full 0-2πrange in azimuthal field distribution.Through rigorous numerical simulations,we systematically established a quantitative correlation between the structural parameters and azimuthal optical field patterns,revealing,for the first time,a quasi-linear relationship between the radius difference and the resultant optical distribution.This theoretical framework advances our fundamental understanding of structured optical field manipulation as well as provides a new paradigm for programmable photonic device design,with distinct technical advantages in super-resolution imaging and optical tweezer systems. 展开更多
关键词 optical manipulation topological charge spiral array
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Earthquake monitoring and high-resolution velocity tomography for the central Longmenshan fault zone by a temporary dense seismic array 被引量:1
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作者 ShaoBo Yang HaiJiang Zhang +4 位作者 MaoMao Wang Ji Gao Shuaijun Wang BaoJin Liu XiWei Xu 《Earth and Planetary Physics》 2025年第2期239-252,共14页
The Longmenshan(LMS)fault zone is located at the junction of the eastern Tibetan Plateau and the Sichuan Basin and is of great significance for studying regional tectonics and earthquake hazards.Although regional velo... The Longmenshan(LMS)fault zone is located at the junction of the eastern Tibetan Plateau and the Sichuan Basin and is of great significance for studying regional tectonics and earthquake hazards.Although regional velocity models are available for the LMS fault zone,high-resolution velocity models are lacking.Therefore,a dense array of 240 short-period seismometers was deployed around the central segment of the LMS fault zone for approximately 30 days to monitor earthquakes and characterize fine structures of the fault zone.Considering the large quantity of observed seismic data,the data processing workflow consisted of deep learning-based automatic earthquake detection,phase arrival picking,and association.Compared with the earthquake catalog released by the China Earthquake Administration,many more earthquakes were detected by the dense array.Double-difference seismic tomography was adopted to determine V_(p),V_(s),and V_(p)/V_(s)models as well as earthquake locations.The checkerboard test showed that the velocity models have spatial resolutions of approximately 5 km in the horizontal directions and 2 km at depth.To the west of the Yingxiu–Beichuan Fault(YBF),the Precambrian Pengguan complex,where most of earthquakes occurred,is characterized by high velocity and low V_(p)/V_(s)values.In comparison,to the east of the YBF,the Upper Paleozoic to Jurassic sediments,where few earthquakes occurred,show low velocity and high V_(p)/V_(s)values.Our results suggest that the earthquake activity in the LMS fault zone is controlled by the strength of the rock compositions.When the high-resolution velocity models were combined with the relocated earthquakes,we were also able to delineate the fault geometry for different faults in the LMS fault zone. 展开更多
关键词 Longmenshan fault zone dense seismic array deep learning double-difference seismic tomography seismic velocity model earthquake locations fault geometry
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Ultrafast Self-powered Near-infrared Photodetectors and Imaging Array Based on Tin-lead Mixed Perovskites
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作者 LIU Jingjing YANG Zhichun +7 位作者 BAO Haotian MENG Xinqin QI Minru YANG Changgang ZHANG Guofeng QIN Chengbing XIAO Liantuan JIA Suotang 《发光学报》 北大核心 2025年第6期1037-1047,共11页
Tin-lead(Sn-Pb)mixed perovskites are extensively investigated in near-infrared(NIR)photodetectors(PDs)owing to their excellent photoelectric performance.However,achieving high-performance Sn-Pb mixed PDs remains chall... Tin-lead(Sn-Pb)mixed perovskites are extensively investigated in near-infrared(NIR)photodetectors(PDs)owing to their excellent photoelectric performance.However,achieving high-performance Sn-Pb mixed PDs remains challenging,primarily because of the rapid crystallization and the susceptibility of Sn^(2+) to oxidation.To ad⁃dress these issues,this study introduces the multifunctional molecules 2,3-difluorobenzenamine(DBM)to modulate the crystallization of Sn-Pb mixed perovskites and retard the oxidation of Sn^(2+),thereby significantly enhancing film quality.Compared with the pristine film,Sn-Pb mixed perovskite films modulated by DBM molecules exhibit a high⁃ly homogeneous morphology,reduced roughness and defect density.The self-powered NIR PDs fabricated with the improved films have a spectral response range from 300 nm to 1100 nm,a peak responsivity of 0.51 A·W^(-1),a spe⁃cific detectivity as high as 2.46×10^(11)Jones within the NIR region(780 nm to 1100 nm),a linear dynamic range ex⁃ceeding 152 dB,and ultrafast rise/fall time of 123/464 ns.Thanks to the outstanding performance of PDs,the fabri⁃cated 5×5 PDs array demonstrates superior imaging ability in the NIR region up to 980 nm.This work advances the development of Sn-Pb mixed perovskites for NIR detection and paves the way for their commercialization. 展开更多
关键词 tin-lead mixed perovskites near-infrared photodetectors imaging array oxidation crystallization modulation
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Investigation on the Influence of Mooring System Configuration on the Hydrodynamic Performance of an Oscillating Water Column Array System
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作者 XU Sheng JU Kun +2 位作者 JI Chun-yan DAI Sai-shuai YUAN Zhi-ming 《China Ocean Engineering》 2025年第6期1054-1069,共16页
This paper presents a multi-module oscillating water column(OWC)wave energy converter(WEC)array system,comprising seven interconnected OWC modules.The modules are connected by elastic ropes with clumped weights positi... This paper presents a multi-module oscillating water column(OWC)wave energy converter(WEC)array system,comprising seven interconnected OWC modules.The modules are connected by elastic ropes with clumped weights positioned at the ropes'midpoints.Three distinct mooring systems are designed for this OWC array,and the impact of mooring configurations on the hydrodynamic responses of the OWCs and mooring tensions is thoroughly examined.Three-dimensional potential flow theory is applied to perform time domain analyses.The motion responses of representative modules,the tension of specific mooring lines,and the spacing between adjacent modules in the array system are investigated through a comprehensive coupled dynamic analysis in the time domain.Based on these analyses,recommendations are provided for the optimal mooring system configuration for the array system. 展开更多
关键词 OWC array system mooring system hydrodynamic performance
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Programmable array antenna based on nematic liquid crystals for the Ka-band
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作者 WANG Qiang KE Junchen BAI Lin 《Journal of Southeast University(English Edition)》 2025年第1期78-83,共6页
A programmable low-profile array antenna based on nematic liquid crystals(NLCs)is proposed.Each antenna unit comprises a square patch radiating structure and a tunable NLC-based phase shifter capable of achieving a ph... A programmable low-profile array antenna based on nematic liquid crystals(NLCs)is proposed.Each antenna unit comprises a square patch radiating structure and a tunable NLC-based phase shifter capable of achieving a phase shift exceeding 360°with high linearity.First,the above 64 antenna units are periodically arranged into an 8×8 NLC-based antenna array,and the bias voltage of the NLC-based phase shifter loaded on the antenna unit is adjusted through the control of the field-programmable gate array(FPGA)programming sequences.This configuration enables precise phase changes for all 64 channels.Numerical simulation,sample processing,and experimental measurements of the antenna array are conducted to validate the performance of the antenna.The numerical and experimental results demonstrate that the proposed antenna performs well within the frequency range of 19.5-20.5 GHz,with a 3 dB relative bandwidth of 10%and a maximum main lobe gain of 14.1 dBi.A maximum scanning angle of±34°is achieved through the adjustment of the FPGA programming sequence.This NLC-based programmable array antenna shows promising potential for applications in satellite communication. 展开更多
关键词 array antenna nematic liquid crystals electronically beam scanning field programmable gate array(FPGA)
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