A guidance to intelligent metamaterials and metamaterials intelligence

Nature Communications, Год журнала: 2025, Номер 16(1)

Опубликована: Янв. 29, 2025

Язык: Английский

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Wide-Angle, Polarization-Independent Broadband Metamaterial Absorber by Using Plasmonic Metasurface-Based Split-Circular Structure

Photonics, Год журнала: 2025, Номер 12(4), С. 334 - 334

Опубликована: Апрель 2, 2025

Absorption of electromagnetic waves in a broadband frequency range with polarization insensitivity and wide incidence angles is greatly needed modern technological applications. Many methods using metamaterials have been suggested to address this requirement; they can be complex multilayer structures or use external electronic components. In paper, we present plasmonic metasurface structure that was simply fabricated the standard printed circuit board technique but provided high absorption above 90%, also covering from 12.30 14.80 GHz. This consisted structural unit cells composed multiple split rings connected by copper bar. Analysis, simulation, measurement results showed polarization-insensitive properties maintained an 90% at incident up 45 degrees. The fundamental design used absorber different ranges able adapt well being various scales.

Язык: Английский

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Intelligent Hand‐Gesture Recognition Based on Programmable Topological Metasurfaces

Advanced Functional Materials, Год журнала: 2024, Номер unknown

Опубликована: Авг. 29, 2024

Abstract Intelligent recognition of human positioning, posture, and hand‐gesture based on wireless electromagnetic (EM) induction has recently garnered widespread attention is anticipated to find wide applications in various smart scenarios. Here a novel robust hand gesture method programmable topological metasurfaces presented. By exploiting the programmability surface waves by metasurfaces, multi‐dimensional near‐field coupling pathways are flexibly constructed extract EM feature information corresponding different gestures. An intelligent acquisition system that can rapidly capture metasurface for conditions built. The transmission data thousands gestures train neural network, which achieve accuracy more than 99% 5 single‐hand gestures, 25 two‐hand combinations experimentally collected. It expected proposed scheme will advance research body sensing promote metasurfaces.

Язык: Английский

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Integrated Solution Combining Low-Frequency Forced Oscillation Technique and Continuous Equivital Sensor Monitoring for Assessment of Non-Invasive Ambulatory Respiratory Mechanics

Applied Sciences, Год журнала: 2025, Номер 15(2), С. 751 - 751

Опубликована: Янв. 14, 2025

Early assessment of respiratory mechanics is crucial for early-stage diagnosing and managing lung diseases, leading to greater patient outcomes. Traditional methods like spirometry are limited in continuous monitoring compliance as they require forced maneuvers with significant cooperation, which may not be available fragile individuals. The Forced Oscillation Technique (FOT) a non-invasive measurement method, only based on the tidal breathing at rest from time period. proposed solution integrates low-frequency FOT using Equivital (EQV) sensors enhance information heart rate variability. Data were collected over two-hour period six healthy volunteers, measuring impedance every 7 min continuously recording physiological parameters. best-fitting fractional-order models data identified genetic algorithms. This study also explores correlation between model parameters EQV data, discussing potential AI tools forecasting properties. Our findings indicate that combined techniques analysis provides additional complementary information, subsequently aiding improved evaluation function tissue mechanics. protocol allows ambulatory can easily performed normal conditions.

Язык: Английский

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Multifunctional Topological Metasurfaces with Modular Meta‐Atoms for Multidimensional Wave Control

Advanced Optical Materials, Год журнала: 2025, Номер unknown

Опубликована: Фев. 20, 2025

Abstract Metasurfaces offer precise control over various degrees of freedom electromagnetic (EM) waves. However, their capability to manipulate surface and space EM waves simultaneously remains a formidable challenge. Here, this challenge is addressed by integrating metasurfaces with topological photonics, resulting in that can both full‐space The metasurface composed reusable modular meta‐atoms, exhibiting programmability, reconfigurability, detachability, scalability. low‐cost low‐power platform has big waves, enabling multiple functions such as focusing, holographic imaging, wireless communication, sensing, object classification. efficient manipulations transmitted reflected are experimentally demonstrated encoding the meta‐atoms showcasing programmable constructing topologically protected multi‐channel propagation pathways. redefines paradigm wave manipulation provide unprecedented opportunities for signal enhancement, paving way intelligent multifunctional controls next‐generation sensor communication systems.

Язык: Английский

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Synthesising a Fixed-Length Equispaced Linear Array to Produce Dolph–Chebyshev Patterns with Deep Nulls, a Desired Side Lobe Level and Different Beamwidths

Sensors, Год журнала: 2025, Номер 25(6), С. 1685 - 1685

Опубликована: Март 8, 2025

A method for the synthesis of equally spaced antenna arrays based on extension Orchard–Elliott–Stern technique to radiation patterns with three roots negative real axis Shelkunoff unit circle is presented. One these placed and other two are off coordinates r 1/r. For a desired side lobe level (SLL), allows multiplicity solutions different amplitude ratios, obtained by varying value r, each which presents beamwidths directivity, but fewer lobes than without restrictions in roots. The has been thoroughly applied Dolph–Chebyshev 10, 18 40 elements, λ/2 spacing an SLL that guarantees maximum directivity both cases. This approach ensures study examples all sizes, from small large. findings derived this would be applicable domain wireless communications, where necessity arises exhibit low adaptive beamwidth.

Язык: Английский

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Design, Simulation, and Validation of a Flexible Liquid Metal Reconfigurable Metasurface

Advanced Materials Technologies, Год журнала: 2025, Номер unknown

Опубликована: Март 5, 2025

Abstract In this paper, a continuously reconfigurable metasurface based on liquid metal microfluidics is proposed, which achieves flexible device fabrication, reconfiguration response, and frequency‐tunable performance. The designed unit consists of double‐C‐shape, its frequency can be adjusted in the ranges 3.7–5.72 6.73–7.94 GHz. According to simulation, resonance almost unchanged as NaOH concentration increases, while reflection amplitude first rises then falls, power loss density at resonant increases. Moreover, achieve continuous regulation beneficial attenuation electromagnetic waves lower frequency, compared with solid metasurface. subarray fabricated materials, metal, solution. Subsequently, multi‐directional enable metasurface, state maintained when off. Finally, 30 × cm prototype formed by assembling subarrays. experimental results response are consistent simulation results. This work presents new method for adjustable low consumption, cost, reconfiguration.

Язык: Английский

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Wide-angle optimization method for metamaterial absorber structures

Journal of Applied Physics, Год журнала: 2025, Номер 137(17)

Опубликована: Май 1, 2025

Metamaterial absorbers play an important role in various applications such as radar cross-sectional reduction, electromagnetic interference suppression, and stealth technology. However, the absorption performance of many existing metamaterial decreases significantly with increase incident angle due to distinct variational trends characteristic impedance free space under different polarizations, compared input absorber structures. Here, we propose a method improve oblique incidence by loading additional transmissive layer structure. This structure consists two periodic layers separated air spacer. Simulation results show that proposed has improved stabilized frequency. The absorptivity remains above 87% TE polarization, increases from 0° 85°. is validated experiments, measured agree well numerical simulations. work presents simplified effective methodology reduce complexity designing large angles incidence.

Язык: Английский

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Deep Reinforcement Learning with Local Attention for Single Agile Optical Satellite Scheduling Problem

Sensors, Год журнала: 2024, Номер 24(19), С. 6396 - 6396

Опубликована: Окт. 2, 2024

This paper investigates the single agile optical satellite scheduling problem, which has received increasing attention due to rapid growth in earth observation requirements. Owing complicated constraints and considerable solution space of this conventional exact methods heuristic methods, are sensitive problem scale, demand high computational expenses. Thus, an efficient approach is demanded solve proposes a deep reinforcement learning algorithm with local mechanism. A mathematical model first established describe considers series complex takes profit ratio completed tasks as optimization objective. Then, neural network framework encoder–decoder structure adopted generate high-quality solutions, mechanism designed improve generation solutions. In addition, adaptive rate strategy proposed guide actor–critic training dynamically adjust process enhance effectiveness network. Finally, extensive experiments verify that outperforms comparison algorithms terms quality, generalization performance, computation efficiency.

Язык: Английский

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Self-Organizing and Routing Approach for Condition Monitoring of Railway Tunnels Based on Linear Wireless Sensor Network

Sensors, Год журнала: 2024, Номер 24(20), С. 6502 - 6502

Опубликована: Окт. 10, 2024

Real-time status monitoring is crucial in ensuring the safety of railway tunnel traffic. The primary method currently involves deploying sensors to form a Wireless Sensor Network (WSN). Due linear characteristics tunnels, resulting sensor networks usually have topology known as thick Linear (LWSN). In practice, are deployed randomly within area, and balance energy consumption among nodes extend network's lifespan, this paper proposes self-organizing network routing based on LWSNs. This can discover topology, from nodes, establish adjacency relationships, automatically clusters using timing mechanism. routing, considering cluster heads' load, residual energy, distance sink node, optimal next-hop head selected minimize disparity nodes. Simulation experiments demonstrate that has significant advantages balancing extending lifespan for

Язык: Английский

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