Готові списки джерел за темами / METAMATERIA

Добірка наукової літератури з теми "METAMATERIA"

Автор: Grafiati
Опубліковано: 11 вересня 2023

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Статті в журналах з теми "METAMATERIA"

1

Hamid, Sofian. "Design of Multiband Miniaturized Antenna using Metamaterial Concept for WLAN/WiMAX Application." JURNAL Al-AZHAR INDONESIA SERI SAINS DAN TEKNOLOGI 1, no. 1 (March 4, 2011): 1. http://dx.doi.org/10.36722/sst.v1i1.11.

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Анотація:
Design of low cost multiband antenna is presented. The antenna works in WLAN/WMAX band and has a very compact dimension of 2 cm x 2 cm, making it suitable for handheld devices. This small dimension is achieved since the antenna is loaded with the metamateria element. To miniaturize the antenna dimension further, modification on the left side of ground-plane is introduced, which is inspired by the self complementary antenna concept. Resonance at lower frequency is given by the single cell metamaterial loading on 2.36 – 2.45 frequency; at the middle frequency is given by the thin slot on 3.26 – 3.49 frequency; and at higher frequency is given by the main radiator on 5.3 – 6 GHz frequency. The antenna has omnidirectional pattern and moderate directivity of 2-3 dBi on those frequencies.
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2

Nasiri, Badr, Ahmed Errkik, Jamal Zbitou, Abdelali Tajmouati, Larbi El Abdellaoui, and Mohamed Latrach. "A Compact Planar Low-Pass Filter Based on SRR-Metamateria." International Journal of Electrical and Computer Engineering (IJECE) 8, no. 6 (December 1, 2018): 4972. http://dx.doi.org/10.11591/ijece.v8i6.pp4972-4980.

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Анотація:
In this work, a novel design of a Microstrip Low-pass filter based on metamaterial square split ring resonators (SRRs) is proposed. The SRRs has been added to obtain a reduced size and high performances. The filter is designed on an FR-4 substrate having a thickness of 1.6mm, a dielectric constant of 4.4 and loss tangent of 0.025. The proposed low-pass filter is characterized by a cutoff frequency of 2.4 GHz and an attenuation level below than -20dB in the stopband. The LPF is designed, simulated and optimized by using two electromagnetic solvers CST microwave studio and ADS. The computed results obtained by both solvers are in good agreement. The total surface area of the proposed circuit is 18x18mm2 excluding the feed line, its size is miniaturized by 40% compared to the conventional filter. The experimental results illustrate that the filter achieves very good electrical performances in the passband with a low insertion loss of 0.2 dB. Moreover, a suppression level can reach more than 35 dB in the rejected band.
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3

Tan, Plum, and Singh. "Surface Lattice Resonances in THz Metamaterials." Photonics 6, no. 3 (June 26, 2019): 75. http://dx.doi.org/10.3390/photonics6030075.

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Анотація:
Diffraction of light in periodic structures is observed in a variety of systems including atoms, solid state crystals, plasmonic structures, metamaterials, and photonic crystals. In metamaterials, lattice diffraction appears across microwave to optical frequencies due to collective Rayleigh scattering of periodically arranged structures. Light waves diffracted by these periodic structures can be trapped along the metamaterial surface resulting in the excitation of surface lattice resonances, which are mediated by the structural eigenmodes of the metamaterial cavity. This has brought about fascinating opportunities such as lattice-induced transparency, strong nearfield confinement, and resonant field enhancement and line-narrowing of metamaterial structural resonances through lowering of radiative losses. In this review, we describe the mechanisms and implications of metamaterial-engineered surface lattice resonances and lattice-enhanced field confinement in terahertz metamaterials. These universal properties of surface lattice resonances in metamaterials have significant implications for the design of resonant metamaterials, including ultrasensitive sensors, lasers, and slow-light devices across the electromagnetic spectrum.
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4

Ren, Yi, Minghui Duan, Rui Guo, and Jing Liu. "Printed Transformable Liquid-Metal Metamaterials and Their Application in Biomedical Sensing." Sensors 21, no. 19 (September 22, 2021): 6329. http://dx.doi.org/10.3390/s21196329.

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Анотація:
Metamaterial is becoming increasingly important owing to its unique physical properties and breakthrough applications. So far, most metamaterials that have been developed are made of rigid materials and structures, which may restrict their practical adaptation performances. Recently, with the further development of liquid metal, some efforts have explored metamaterials based on such tunable electronic inks. Liquid metal has high flexibility and good electrical conductivity, which provides more possibilities for transformable metamaterials. Here, we developed a new flexible liquid-metal metamaterial that is highly reconfigurable and could significantly extend the working limit facing current devices. The printed electronics method was adopted to fabricate artificial units and then construct various potential transformable metamaterials. Based on metamaterial theory and printing technology, typical structured flexible liquid-metal electromagnetic metamaterials were designed and fabricated. The electronic and magnetic characteristics of the liquid-metal-based electromagnetic metamaterials were evaluated through simulated analysis and experimental measurement. Particularly, the potential of liquid-metal metamaterials in biomedical sensing was investigated. Further, the future outlook of liquid-metal metamaterials and their application in diverse categories were prospected.
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5

Zhou, Xiaoshu, Qide Xiao, and Han Wang. "Metamaterials Design Method based on Deep learning Database." Journal of Physics: Conference Series 2185, no. 1 (January 1, 2022): 012023. http://dx.doi.org/10.1088/1742-6596/2185/1/012023.

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Анотація:
Abstract In recent years, deep learning has risen to the forefront of many fields, overcoming challenges previously considered difficult to solve by traditional methods. In the field of metamaterials, there are significant challenges in the design and optimization of metamaterials, including the need for a large number of labeled data sets and one-to-many mapping when solving inverse problems. Here, we will use deep learning methods to build a metamaterial database to achieve rapid design and analysis methods of metamaterials. These technologies have significantly improved the feasibility of more complex metamaterial designs and provided new metamaterial design and analysis ideas.
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6

Li, Yafei, Jiangtao Lv, Qiongchan Gu, Sheng Hu, Zhigang Li, Xiaoxiao Jiang, Yu Ying, and Guangyuan Si. "Metadevices with Potential Practical Applications." Molecules 24, no. 14 (July 22, 2019): 2651. http://dx.doi.org/10.3390/molecules24142651.

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Анотація:
Metamaterials are “new materials” with different superior physical properties, which have generated great interest and become popular in scientific research. Various designs and functional devices using metamaterials have formed a new academic world. The application concept of metamaterial is based on designing diverse physical structures that can break through the limitations of traditional optical materials and composites to achieve extraordinary material functions. Therefore, metadevices have been widely studied by the academic community recently. Using the properties of metamaterials, many functional metadevices have been well investigated and further optimized. In this article, different metamaterial structures with varying functions are reviewed, and their working mechanisms and applications are summarized, which are near-field energy transfer devices, metamaterial mirrors, metamaterial biosensors, and quantum-cascade detectors. The development of metamaterials indicates that new materials will become an important breakthrough point and building blocks for new research domains, and therefore they will trigger more practical and wide applications in the future.
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7

Hu, Hua-Liang, Ji-Wei Peng, and Chun-Ying Lee. "Dynamic Simulation of a Metamaterial Beam Consisting of Tunable Shape Memory Material Absorbers." Vibration 1, no. 1 (July 18, 2018): 81–92. http://dx.doi.org/10.3390/vibration1010007.

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Анотація:
Metamaterials are materials with an artificially tailored internal structure and unusual physical and mechanical properties such as a negative refraction coefficient, negative mass inertia, and negative modulus of elasticity, etc. Due to their unique characteristics, metamaterials possess great potential in engineering applications. This study aims to develop new acoustic metamaterials for applications in semi-active vibration isolation. For the proposed state-of-the-art structural configurations in metamaterials, the geometry and mass distribution of the crafted internal structure is employed to induce the local resonance inside the material. Therefore, a stopband in the dispersion curve can be created because of the energy gap. For conventional metamaterials, the stopband is fixed and unable to be adjusted in real-time once the design is completed. Although the metamaterial with distributed resonance characteristics has been proposed in the literature to extend its working stopband, the efficacy is usually compromised. In order to increase its adaptability to time-varying disturbance, several semi-active metamaterials have been proposed. In this study, the incorporation of a tunable shape memory alloy (SMA) into the configuration of metamaterial is proposed. The repeated resonance unit consisting of SMA beams is designed and its theoretical formulation for determining the dynamic characteristics is established. For more general application, the finite element model of this smart metamaterial is also derived and simulated. The stopband of this metamaterial beam with different configurations in the arrangement of the SMA absorbers was investigated. The result shows that the proposed model is able to predict the unique dynamic characteristics of this smart metamaterial beam. Moreover, the tunable stopband of the metamaterial beam with controlling the state of SMA absorbers was also demonstrated.
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8

Gu, Leilei, Hongzhan Liu, Zhongchao Wei, Ruihuan Wu, and Jianping Guo. "Optimized Design of Plasma Metamaterial Absorber Based on Machine Learning." Photonics 10, no. 8 (July 27, 2023): 874. http://dx.doi.org/10.3390/photonics10080874.

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Анотація:
Metamaterial absorbers have become a popular research direction due to their broad application prospects, such as in radar, infrared imaging, and solar cell fields. Usually, nanostructured metamaterials are associated with a large number of geometric parameters, and traditional simulation designs are time consuming. In this paper, we propose a framework for designing plasma metamaterial absorbers in both a forward prediction and inverse design composed of a primary prediction network (PPN) and an auxiliary prediction network (APN). The framework can build the relationship between the geometric parameters of metamaterials and their optical response (reflection spectra, absorption spectra) from a large number of training samples, thus solving the problem of time-consuming and case-by-case numerical simulations in traditional metamaterial design. This framework can not only improve forward prediction more accurately and efficiently but also inverse design metamaterial absorbers from a given required optical response. It was verified that it is also applicable to absorbers of different structures and materials. Our results show that it can be used in metamaterial absorbers, chiral metamaterials, metamaterial filters, and other fields.
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9

Kaschke, Johannes, and Martin Wegener. "Optical and Infrared Helical Metamaterials." Nanophotonics 5, no. 4 (September 1, 2016): 510–23. http://dx.doi.org/10.1515/nanoph-2016-0005.

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Анотація:
AbstractBy tailoring metamaterials with chiral unit cells, giant optical activity and strong circular dichroism have been achieved successfully over the past decade. Metamaterials based on arrays of metal helices have revolutionized the field of chiral metamaterials, because of their capability of exhibiting these pronounced chiro-optical effects over previously unmatched bandwidths. More recently, a large number of new metamaterial designs based on metal helices have been introduced with either optimized optical performance or other chiro-optical properties for novel applications.The fabrication of helical metamaterials is, however, challenging and even more so with growing complexity of the metamaterial designs. As conventional two-dimensional nanofabrication methods, for example, electron-beam lithography, are not well suited for helical metamaterials, the development of novel three-dimensional fabrication approaches has been triggered.Here, we will discuss the theory for helical metamaterials and the principle of operation. We also review advancements in helical metamaterial design and their limitations and influence on optical performance. Furthermore, we will compare novel nano- and microfabrication techniques that have successfully yielded metallic helical metamaterials. Finally, we also discuss recently presented applications of helical metamaterials extending beyond the use of far-field circular polarizers.
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10

Hou, Zheyu, Pengyu Zhang, Mengfan Ge, Jie Li, Tingting Tang, Jian Shen, and Chaoyang Li. "Metamaterial Reverse Multiple Prediction Method Based on Deep Learning." Nanomaterials 11, no. 10 (October 11, 2021): 2672. http://dx.doi.org/10.3390/nano11102672.

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Анотація:
Metamaterials and their related research have had a profound impact on many fields, including optics, but designing metamaterial structures on demand is still a challenging task. In recent years, deep learning has been widely used to guide the design of metamaterials, and has achieved outstanding performance. In this work, a metamaterial structure reverse multiple prediction method based on semisupervised learning was proposed, named the partially Conditional Generative Adversarial Network (pCGAN). It could reversely predict multiple sets of metamaterial structures that can meet the needs by inputting the required target spectrum. This model could reach a mean average error (MAE) of 0.03 and showed good generality. Compared with the previous metamaterial design methods, this method could realize reverse design and multiple design at the same time, which opens up a new method for the design of new metamaterials.
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Більше джерел

Дисертації з теми "METAMATERIA"

1

Ni, Sisi (Sisi Sophie). "Phononic metamaterials based on complex geometries : "a new kind of metamaterial"." Thesis, Massachusetts Institute of Technology, 2014. http://hdl.handle.net/1721.1/89957.

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Анотація:
Thesis: Ph. D., Massachusetts Institute of Technology, Department of Materials Science and Engineering, 2014.
Cataloged from PDF version of thesis.
Includes bibliographical references.
Facing the growing challenges of energy, environment, security and disease treatment, the demand for novel materials are growing. While the material centric approach have resulted in development of new materials for advanced applications, we introduce a geometric approach as a complementary point of view for further innovation in this ever expanding and growing field. Inspired by the ubiquitous fractals-like geometry of in natures, the scale transformation (i.e. dilation or contraction) is included in the framework since fractal geometries shows structures at all scales (usually discrete and finite in physical world). We developed our framework using metamaterials since it enable us to design "atoms" or "molecules" and their relative arrangement with greater freedom (i.e. not limited by the chemical bond or ionic bond in classical materials system). We studied metamaterials using prefractals from both exact-self similar fractal and random fractal samples. For exact-self similar fractals, we choose H tree based prefractals and Hilbert Curve prefractals bounded system given their unique geometric properties and wide applications. Guided by the framework, we investigated several key parameters (e.g. level of iteration, geometric anisotropy, impedance contrast, arrangement of subunit, resolution) that would dictate the dispersion behavior of the system. It was found that for exact-self similar prefractals, multiple spectrum bandgaps (i.e. broadband response) can be achieved with increased level of iterations where translation symmetry is imposed through boundary condition. Furthermore, the transition from scale dependence and independent described by the general framework has been observed for all the samples we studied. Furthermore, for single prefractal resonator, subwavelength (~1/75[lambda]) behavior has been observed and explained using a simple analytical model. For metamaterials based on fractional Brownian motion, the Hurst constant is found to be a good indicator of phononic behavior of the system, besides other parameters studied. Our findings does not only expand the repertoire for novel materials by introducing the ubiquitous yet unconventional geometry to metamaterials; but also have interdisciplinary applications in biology, seismology, arts, hence shine lights on our understanding of nature.
by Sisi (Sophie) Ni.
Ph. D.
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2

Macêdo, Jorge Andrey da Silva. "Formalismo FDTD para a modelagem de meios dispersivos apresentando anisotropia biaxial." Universidade de São Paulo, 2008. http://www.teses.usp.br/teses/disponiveis/18/18155/tde-15102008-135510/.

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Анотація:
Este trabalho apresenta um novo formalismo bi-dimensional em diferenças finitas no domínio do tempo (2D-FDTD) para a simulação de estruturas baseadas em metamateriais. A natureza dispersiva destes meios é levada em consideração de forma precisa pela inclusão dos modelos materiais de Drude para os tensores permissividade elétrica e permeabilidade magnética. Todos os elementos dos tensores são considerados neste formalismo, o que o torna muito atraente para a modelagem de uma classe geral de estruturas eletromagnéticas. Dois efeitos de enorme impacto são analisados em detalhes, sendo eles a cobertura de invisibilidade e o rotacionamento de campo. Ambos os efeitos requerem a utilização de técnicas de transformação de coordenadas a qual deve ser aplicada apenas na região onde os campos eletromagnéticos precisam ser manipulados, tirando vantagem da invariância das equações de Maxwell quanto a estas operações. Esta técnica redefine localmente os parâmetros de permissividade e permeabilidade do meio transformado. O formalismo implementado apresentou grande estabilidade e precisão, uma conseqüência direta da natureza dispersiva dos modelos materiais de Drude, o que o caracteriza como uma boa contribuição para uma completa compreensão da fenomenologia por trás destes efeitos fascinantes. Os resultados numéricos apresentaram boa concordância com os disponíveis na literatura. Foi também observado que ambas estruturas são muito sensíveis a variações de freqüência do campo de excitação.
This work introduces an extended two-dimensional finite difference time domain method (2D-FDTD) for the simulation of metamaterial based structures. The dispersive nature of these media is accurately taken into account through the inclusion of the Drude material models for the permittivity and permeability tensors. All tensor elements are properly accounted for, making the formalism quite attractive for the modeling of a general class of electromagnetic structures. Two striking effects are investigated with the proposed model, namely, the invisibility cloaking and the field rotation effects. Both effects require the utilization of a coordinate transformation technique which must be applied only in the region where the electromagnetic field needs to be manipulated, taking advantage of the invariance of Maxwell\'s equations with respect to these operations. This technique locally redefines the permittivity and permeability parameters of the transformed media. The implemented formalism has proved to be quite stable and accurate, a direct consequence of the dispersive nature of the Drude material model, which characterizes it as a good contribution to fully understand the phenomenology behind these fascinating effects. The numerical results are in good agreement with those available in the literature. It was also verified that both structures are very sensitive to frequency variations of the excitation field.
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3

Martínek, Luděk. "Antény s kryty z metamateriálů." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2013. http://www.nusl.cz/ntk/nusl-219978.

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Анотація:
This thesis deals with microstrip antennas covered by the metamaterials. First, are described planar antennas, their problems and the emergence of surface waves. Surface waves can cause unwanted coupling among particular parts of the structure and can degrade its parameters. The problem can be solved using an electromagnetic band gap structure (EBG). These periodic structures are able to suppress surface waves in different frequency bands. It is shown how the EBG structure in the function superstate improve directivity and antenna gain. Radiation conventional microstrip antenna with metallo-dielectric EBG superstrate and with the purely dielectric double-layer superstrate is described. The both structures are designed and simulated in CST Microwave Studio program. Further is described the antenna radiation with so-called mushroom structure and metallo-dielectric EBG superstate. The structure is again designed and simulated in CST MWS program. Finally, there are two structures with metallo-dielectric superstate implemented and measured.
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4

Sartori, Eduardo Jose. "Metodologia experimental de desenvolvimento de grades metamateriais com permissividade quase-zero e negativa." [s.n.], 2009. http://repositorio.unicamp.br/jspui/handle/REPOSIP/260806.

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Анотація:
Orientador: Hugo E. Hernandez Figueroa
Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Eletrica e de Computação
Made available in DSpace on 2018-08-14T23:26:41Z (GMT). No. of bitstreams: 1 Sartori_EduardoJose_D.pdf: 11903812 bytes, checksum: 6e06f001155d33b841c61ae93464c897 (MD5) Previous issue date: 2009
Resumo: Metamateriais são estruturas ou arranjos geométricos feitos a partir de materiais comuns, dielétricos, condutores, magnéticos ou por combinação destes. Os metamateriais caracterizam-se principalmente por apresentarem propriedades especiais de permissividade ( e) e permeabilidade ( µ) não encontradas nos materiais em estado natural, cujo principal efeito é o índice negativo de refração (n < 0). Essas características permitem seu emprego em diversos tipos de aplicações em eletromagnetismo e óptica, tais como filtros passa-faixa e rejeita-faixa, espelhos dielétricos, super lentes etc. Normalmente, o equacionamento envolvido no cálculo de parâmetros dos metamateriais são complexos e, na maioria das vezes, necessitam de apoio computacional. Por este motivo, o presente trabalho traz um estudo experimental sobre dois tipos de comportamento metamaterial, o de permissividade quase-zero e negativa, analisando seu desempenho sob vários aspectos geométricos e de características dos materiais envolvidos, além de propor uma metodologia de desenvolvimento, a qual possibilita um rápido dimensionamento de diversos tipos de grades metamateriais, baseada em cálculos simples ou consulta direta a tabelas e curvas de projeto.
Abstract: Metamaterials are structures or geometric arrangements made from common materials, dielectrics, conductors, magnetic or a combination of these. Metamaterials are characterized mainly because of their special characteristics of permittivity ( e) and permeability ( µ), not found in the materials at natural state, whose main effect is the negative index of refraction (n <0). These characteristics allow its use in several types of applications in electromagnetism and optics, such as band-pass and band-stop filters, dielectric mirrors, super lenses etc.. Typically, the equations involved in the calculation of parameters of metamaterials are complex and, in most cases, require high capability computational methods. For this reason, this work presents an experimental study on two types of metamaterial behavior, near-zero and negative permittivity, examining its performance in several geometric aspects and characteristics of the materials involved, and propose a development methodology, which allows a fast scaling of various types of metamaterials grids, based on simple calculations or direct consultation tables and curves design.
Doutorado
Telecomunicações e Telemática
Doutor em Engenharia Elétrica
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5

Strikwerda, Andrew. "Metamaterial enhanced coupling." Thesis, Boston University, 2012. https://hdl.handle.net/2144/31611.

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Анотація:
Thesis (Ph.D.)--Boston University
PLEASE NOTE: Boston University Libraries did not receive an Authorization To Manage form for this thesis or dissertation. It is therefore not openly accessible, though it may be available by request. If you are the author or principal advisor of this work and would like to request open access for it, please contact us at open-help@bu.edu. Thank you.
In the past decade interest in metamaterials has risen dramatically. This is due, in large part, to metamaterials' ability to exhibit electromagnetic behavior not normally found in nature. This is because these artificial structures display a strong electromagnetic response as a result of their geometry, as opposed to their chemistry, and that response typically dominates that of the substrate they are placed on. As a result, metamaterials can couple free space radiation in previously unheard of ways, and in this thesis I examine several of these coupling mechanisms. After an appropriate discussion of theoretical and experimental tools required for metamaterial study, the thesis turns to the metamaterial substrate and explores the coupling effects of the metamaterial and the substrate itself. We discuss the theory and experimentally demonstrate that the metamaterial and substrate composite can couple free space radiation for use in enhanced dielectric sensing, perfect absorption, and even mechanical deflection for electromagnetic detection. In addition to coupling with dielectric materials, the near field response of a metamaterial can also couple with another metamaterial. Subsequently, this thesis investigates the coupling between a pair of identical split ring resonators, and develops a general framework for evaluating the mode hybridization that results from their near field interaction. In fact, we find that the near field coupling is extremely sensitive to the relative orientation of the two metamaterials, and results in mode splitting between the two resonators. By manipulating their lateral displacement, the coupling, and the mode splitting, can be altered. In this way, an unprecedented modulation of the metamaterial response is demonstrated. Finally, we turn our attention to the effects that metamaterial behavior has on the far field response. Specifically, we focus on the symmetry, or lack thereof, of the unit cell and show that it manifests itself as a birefringence in the far field. As a result, metamaterials can be used as wave retarders to couple between polarization states. Herein we analyze this behavior and experimentally demonstrate functioning metamaterial based terahertz waveplates that are highly efficient at a previously unachieved sub wavelength size.
2031-01-01
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6

Li, Lianbo. "Metamaterial based superdirectivity." Thesis, University of Oxford, 2017. https://ora.ox.ac.uk/objects/uuid:65f10679-cbf2-4c86-897e-8121225c44eb.

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Анотація:
A model-supporting, simple, compact, robust and high efficiency two- element parasitic superdirective array comprising electrically small reso- nant metamaterial elements, namely singly split resonator rings (SSRRs), is predicted by an analytical model and is verified by CST simulation re- sults. The analytical model is built by combining a method of calculating a two-SSRR array's far fild radiated energy density and a well working equivalent circuit for a two-SSRR parasitic array. This model is capable of easily but accurately predicting the far field radiation behaviours of an electrically small parasitic array of two SSRRs (the two SSRRs are not necessarily standard and identical), based on certain information of the array, namely the SSRRs' dimensions, the SSRRs' electrical components (L, C and R), the SSRRs' rotating orientation angles (α1 and α2), the two SSRRs's separation (d) and the array's operation frequency. The impor- tance of this analytical model in designing parasitic superdirective arrays is discussed. Simulation results show that the model predicted two-SSRR parasitic superdirective structure (the `CC' structure) can achieve an end- fire directivity of 4.36, with an elements' separation d = 4mm working at 1:914GHz, and can maintain an efficiencyciency as high as 98:6%. After a short discussion of the design principle behind the `CC' structure, improved su- perdirective structures of are identified and studied based on simulation results. Among these structures, the 'CCLr' structure can achieve the largest directivity value of 5.06 (very close to 5.25, the theoretical limit value of a two-dipole array) with a moderate efficiency of 81:4%. A com- parison between these two-SSRR parasitic superdirective structures (the `CC' and its improved versions) and two commercial two-element Yagi an- tennas show that these two-SSRR structures achieve better directive per- formances than the commercial two-element Yagi antennas do. Through performing the study of near field energy ow for magnetic dipole based structures (analytical results) and SSRR based structures (simulation re- sults), with the help of the concept of causal surfaces, the physical reason behind the superdirectivity phenomenon is revealed.
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7

Shepard, III Ralph Hamilton. "Metamaterial Lens Design." Diss., The University of Arizona, 2009. http://hdl.handle.net/10150/194734.

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Анотація:
Developments in nanotechnology and material science have produced optical materials with astonishing properties. Theory and experimentation have demonstrated that, among other properties, the law of refraction is reversed at an interface between a naturally occurring material and these so-called metamaterials. As the technology advances metamaterials have the potential to vastly impact the field of optical science.In this study we provide a foundation for future work in the area of geometric optics and lens design with metamaterials. The concept of negative refraction is extended to derive a comprehensive set of first-order imaging principles as well as an exhaustive aberration theory to 4th order. Results demonstrate congruence with the classical theory; however, negative refraction introduces a host of novel properties. In terms of aberration theory, metamaterials present the lens designer with increased flexibility. A singlet can be bent to produce either positive or negative spherical aberration (regardless of its focal length), its contribution to coma can become independent of its conjugate factor, and its field curvature takes on the opposite sign of its focal power. This is shown to be advantageous in some designs such as a finite conjugate relay lens; however, in a wider field of view landscape lens we demonstrate a metamaterial's aberration properties may be detrimental.This study presents the first comprehensive investigation of metamaterial lenses using industry standard lens design software. A formal design study evaluates the performance of doublet and triplet lenses operating at F/5 with a 100 mm focal length, a 20° half field of view, and specific geometric constraints. Computer aided optimization and performance evaluation provide experimental controls to remove designer-induced bias from the results. Positive-index lenses provide benchmarks for comparison to metamaterial systems subjected to identical design constraints. We find that idiosyncrasies in a metamaterial lens' aberration content can be exploited to produce imaging systems that are superior to their conventional counterparts. However, in some circumstances the reduced low-order aberration content in a metamaterial lens reduces the effectiveness of aberration balancing and stop shifting. Through a series of design experiments the relative advantages and challenges of using metamaterials in lens design are revealed.
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Ekmekci, Evren. "Design, Fabrication And Characterization Of Novel Metamaterials In Microwave And Terahertz Regions: Multi-band, Frequency-tunable And Miniaturized Structures." Phd thesis, METU, 2010. http://etd.lib.metu.edu.tr/upload/12612730/index.pdf.

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This dissertation is focused on the design, fabrication, and characterization of novel metamaterials in microwave and terahertz regions with the following outcomes: A planar µ
-negative metamaterial structure, called double-sided SRR (DSRR), is proposed in the first part of this study. DSRR combines the features of a conventional split ring resonator (SRR) and a broadside-coupled SRR (BC-SRR) to obtain much better miniaturization at microwave frequencies for a given physical cell size. In addition to DSRR, double-sided multiple SRR (DMSRR), double-sided spiral resonator (DSR), and double-sided U-spiral resonator (DUSR) have been shown to provide smaller electrical sizes than their single-sided versions under magnetic excitation. In the second part of this dissertation, a novel multi-band tunable metamaterial topology, called micro-split SRR (MSSRR), is proposed. In addition to that, a novel magnetic resonator structure named single loop resonator (SLR) is suggested to provide two separate magnetic resonance frequencies in addition to an electric resonance in microwave region. In the third part, two different frequency tunable metamaterial topologies called BC-SRR and gap-to-gap SRR are designed, fabricated and characterized at terahertz frequencies with electrical excitation for the first time. In those designs, frequency tuning based on variations in near field coupling is obtained by in-plane horizontal or vertical displacements of the two SRR layers. The values of frequency shifts obtained for these tunable metamaterial structures are reported to be the highest values obtained in literature so far. Finally, in the last part of this dissertation, novel double-sided metamaterial based sensor topologies are suggested and their feasibility studies are presented.
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Tan, Szu Hau. "Metamaterial for Radar Frequencies." Thesis, Monterey, California. Naval Postgraduate School, 2012. http://hdl.handle.net/10945/17465.

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Approved for public release; distribution is unlimited
The objective of this thesis is to investigate a new design of periodic metamaterial (MTM) structure for radar cross-section (RCS) reduction application on aircraft and ships. MTMs are man-made materials, not found in nature, that exhibit unusual properties in the radio-, electromagnetic-, and optical-wave bands. The cells of these periodic MTM structures must be much smaller than the wavelength of the frequency of interest. In a MTM, the structure and dimensions of the design at the frequency of interest can produce negative values of permeability and/or permittivity, which define the electrical properties of the MTM. This study looks at various designs of absorbing layers presented in technical papers and verifies the results in simulations. Modifications are done to the existing designs to achieve good absorption level at the radar-frequency band of interest. Modeling and simulation are done in Microwave Studio by Computer Simulation Technology (CST). The S-parameters S11 (reflection coefficient) and S12 (transmission coefficient) are used to investigate the performance of the MTM as a radar-frequency absorber.
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10

Demetriadou, Angela. "Studies of metamaterial structures." Thesis, Imperial College London, 2010. http://hdl.handle.net/10044/1/11396.

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Книги з теми "METAMATERIA"

1

Metamateriaru no gijutsu to ōyō: Technologies and applications of metamaterial. Tōkyō: Shīemushī Shuppan, 2011.

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Choudhury, Pankaj K. Metamaterials. Boca Raton: CRC Press, 2021. http://dx.doi.org/10.1201/9781003050162.

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Engheta, Nader, and Richard W. Ziolkowski, eds. Metamaterials. Hoboken, NJ, USA: John Wiley & Sons, Inc., 2006. http://dx.doi.org/10.1002/0471784192.

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Cui, Tie Jun, David Smith, and Ruopeng Liu, eds. Metamaterials. Boston, MA: Springer US, 2010. http://dx.doi.org/10.1007/978-1-4419-0573-4.

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Craster, Richard V., and Sébastien Guenneau, eds. Acoustic Metamaterials. Dordrecht: Springer Netherlands, 2013. http://dx.doi.org/10.1007/978-94-007-4813-2.

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Sakoda, Kazuaki, ed. Electromagnetic Metamaterials. Singapore: Springer Singapore, 2019. http://dx.doi.org/10.1007/978-981-13-8649-7.

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Cai, Wenshan, and Vladimir Shalaev. Optical Metamaterials. New York, NY: Springer New York, 2010. http://dx.doi.org/10.1007/978-1-4419-1151-3.

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Ahmadivand, Arash, Burak Gerislioglu, and Zeinab Ramezani. Toroidal Metamaterials. Cham: Springer International Publishing, 2021. http://dx.doi.org/10.1007/978-3-030-58288-3.

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Rout, Saroj, and Sameer Sonkusale. Active Metamaterials. Cham: Springer International Publishing, 2017. http://dx.doi.org/10.1007/978-3-319-52219-7.

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Caloz, Christophe. Electromagnetic Metamaterials. New York: John Wiley & Sons, Ltd., 2005.

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Частини книг з теми "METAMATERIA"

1

Chipouline, Arkadi, and Franko Küppers. "Applications of the “Classical” Metamaterial Model—Disordered Metamaterials." In Optical Metamaterials: Qualitative Models, 145–66. Cham: Springer International Publishing, 2018. http://dx.doi.org/10.1007/978-3-319-77520-3_7.

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Xu, Liu-Jun, and Ji-Ping Huang. "Theory for Thermoelectric Effect Control: Transformation Nonlinear Thermoelectricity." In Transformation Thermotics and Extended Theories, 35–51. Singapore: Springer Nature Singapore, 2022. http://dx.doi.org/10.1007/978-981-19-5908-0_4.

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AbstractTemperature-dependent (nonlinear) transformation thermotics provides a powerful tool for designing multifunctional, switchable, or intelligent metamaterials in diffusion systems. However, its extension to multiphysics remains studied, in which the temperature dependence of intrinsic parameters is ubiquitous. Here, we theoretically establish a temperature-dependent transformation method for controlling multiphysics. Taking thermoelectric transport as a typical case, we prove the form invariance of its temperature-dependent governing equations and formulate the corresponding transformation rules. Our finite-element simulations demonstrate robust thermoelectric cloaking, concentrating, and rotating performance in temperature-dependent backgrounds. We further design two practical applications with temperature-dependent transformation: an ambient-responsive cloak-concentrator thermoelectric device that can switch between cloaking and concentrating; an improved thermoelectric cloak with nearly-thermostat performance inside. Our theoretical frameworks and application designs may provide guidance for efficiently controlling temperature-related multiphysics and enlighten subsequent intelligent multiphysical metamaterial research.
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Salvatore, Stefano. "Metamaterial Sensors." In Springer Theses, 71–76. Cham: Springer International Publishing, 2014. http://dx.doi.org/10.1007/978-3-319-05332-5_8.

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4

Vakula, D., and A. Sowjanaya. "Metamaterial Filters." In Metamaterials Science and Technology, 1–22. Singapore: Springer Nature Singapore, 2022. http://dx.doi.org/10.1007/978-981-15-8597-5_30-1.

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Vakula, D., and A. Sowjanaya. "Metamaterial Filters." In Metamaterials Science and Technology, 355–75. Singapore: Springer Nature Singapore, 2022. http://dx.doi.org/10.1007/978-981-16-6441-0_30.

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Fedotov, Vassili. "Metamaterials." In Springer Handbook of Electronic and Photonic Materials, 1. Cham: Springer International Publishing, 2017. http://dx.doi.org/10.1007/978-3-319-48933-9_56.

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Trügler, Andreas. "Metamaterials." In Optical Properties of Metallic Nanoparticles, 171–84. Cham: Springer International Publishing, 2016. http://dx.doi.org/10.1007/978-3-319-25074-8_9.

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Hoke, Tomas. "Metamaterials." In Emanzipation und Konfrontation, 60–63. Vienna: Springer Vienna, 2009. http://dx.doi.org/10.1007/978-3-211-89016-5_15.

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McGurn, Arthur. "Metamaterials." In Springer Series in Optical Sciences, 305–83. Cham: Springer International Publishing, 2018. http://dx.doi.org/10.1007/978-3-319-77072-7_5.

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Kužel, Petr, and Hynek Němec. "Metamaterials." In Terahertz Spectroscopy and Imaging, 569–610. Berlin, Heidelberg: Springer Berlin Heidelberg, 2012. http://dx.doi.org/10.1007/978-3-642-29564-5_22.

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Тези доповідей конференцій з теми "METAMATERIA"

1

Mir, Fariha, and Sourav Banerjee. "Performance of a Multifunctional Spiral Shaped Acoustic Metamaterial With Synchronized Low-Frequency Noise Filtering and Energy Harvesting Capability." In ASME 2020 Conference on Smart Materials, Adaptive Structures and Intelligent Systems. American Society of Mechanical Engineers, 2020. http://dx.doi.org/10.1115/smasis2020-2264.

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Abstract Metamaterials are man-made materials that behave uniquely and possess exclusively desired properties that are not found in natural materials. Usually, it is the combination of two or more materials and can be engineered to perform tasks that are not possible with traditional materials. These were initially discovered while working with electromagnetic radiation. Apart from electromagnetic radiation, metamaterials are also capable of affecting the wave propagation characteristics through any fluid such as air. These metamaterials are called acoustic metamaterials. Many acoustic metamaterials have gone beyond its definition but still, characterize the waveguiding properties. Incorporation of smart materials while constructing acoustic metamaterial, can achieve multifunctionality of the design. A prospective application field for such acoustic metamaterials is energy harvesting from low-frequency vibration. It is conceptualized that acoustic metamaterials can be used as noise barrier materials to filter roadside and industrial noise. This application can get extended to the aerospace application where engine noise mitigation inside the cabin is a challenge. In this article, a spiral-shaped acoustic metamaterial is modeled which has a dual function of noise filtering and energy harvesting. This acoustic metamaterial has a comparatively high reflection coefficient closer to the anti-resonance frequencies, resulting in high sound transmission loss. The filtered noise is trapped inside the cell in the form of strain energy. Hence, we claim that if the trapped energy which is any way wasted in the material could be harvested to power the local electronic devices, the new solution could make transformative for the 21st century’s green energy solution. Calculated placement of smart materials in the cell-matrix can help to extract the strain energy in the form of power. The acoustic metamaterial cell presented in this work has the capability of isolating noise and reducing diffraction by trapping sound in low frequencies and at the same time recover the trapped abundant energy in the form of electrical potential using piezoelectric materials. The spiral design is sensitive to vibration due to trampoline shaped attachments inside the cell. This makes it capable of harvesting energy using vibration also. This is a promising acoustoelastic metamaterial with multifunctionality properties for future applications.
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Song, Yu, Sansriti Saxena, Justin Bishop, and Ryan L. Harne. "Constraint Tuning of Lightweight Elastomeric Metamaterials for Structural Impact Tolerance." In ASME 2017 Conference on Smart Materials, Adaptive Structures and Intelligent Systems. American Society of Mechanical Engineers, 2017. http://dx.doi.org/10.1115/smasis2017-3910.

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To alleviate wave and vibration transmission in automotive, aerospace, and civil engineering fields, researchers have investigated periodic metamaterials with especially architected internal topologies. Yet, these solutions employ heavy materials and narrowband, resonant phenomena that are unsuitable for the many applications where broadband frequency vibration energy is a concern, such as that injected by impact forces, and weight is a performance penalty. To overcome these limitations, a new idea for lightweight, elastomeric metamaterials constrained near critical points is recently being explored, such that improved shock and vibration damping is achieved using reduced mass than conventional periodic metamaterials. On the other hand, the internal architectures of these metamaterials have not been explored beyond classical circular designs whereas numerous engineering structures involve square or rectangular geometries that may challenge the ability to realize critical point constraints due to the lack of rotational symmetry. The objectives of this research are to undertake a first study of square cross-section elastomeric metamaterials and to assess the impact tolerance of structures into which these metamaterials are embedded and constrained. Finite element simulations guide attention to design parameters for the metamaterial architectures, while experimental efforts quantify the advantages of constraints on enhancing impact tolerance metrics for engineering structures. It is seen that although the architected metamaterial leads to slightly greater instantaneous acceleration amplitude immediately after impact, it more rapidly attenuates the injected energy when compared to the solid and heavier elastomer mass from which the metamaterial is derived.
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LeGrande, Joshua, Mohammad Bukhari, and Oumar Barry. "Topological Properties and Localized Vibration Modes in Quasiperiodic Metamaterials With Electromechanical Local Resonators." In ASME 2022 International Design Engineering Technical Conferences and Computers and Information in Engineering Conference. American Society of Mechanical Engineers, 2022. http://dx.doi.org/10.1115/detc2022-90025.

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Abstract Simultaneous energy harvesting and vibration attenuation has been a topic of great interest in many recent investigations in mechanical metamaterials. These studies have shown the ability to harvest electrical power using weak electromechanical coupling in periodic metamaterials with no effect on the material’s bandgap boundaries. However, the effect of the electromechanical resonator on the topological properties (i.e. the bandgap topology) and localized mode shapes of a quasiperiodic metamaterial has not yet been determined. In this paper, we study a quasiperiodic metamaterial coupled to electromechanical resonators to observe its bandgaps and localized vibration modes. We show here the analytical dispersion surfaces of an infinite quasiperiodic metamaterial with electromechanical local resonators. The natural frequencies of a semi-infinite system are also simulated numerically to validate the analytical results and show the band structure for different quasiperiodic patterns, load resistors, and electromechanical coupling coefficients. Furthermore, the mode shapes are presented here for a semi-infinite structure showing localized vibration within the bandgaps. The results demonstrate that quasiperiodic metamaterials with electromechanical local resonators can be used to harvest energy without changing the topology of the bandgaps for the case of weak electromechanical coupling. The observations given here can be used to guide designers in choosing electromechanical resonator parameters and quasiperiodic pattern parameters for an effective energy harvesting metamaterial.
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Vogiatzis, Panagiotis, Shikui Chen, Xianfeng David Gu, Ching-Hung Chuang, Hongyi Xu, and Na Lei. "Multi-Material Topology Optimization of Structures Infilled With Conformal Metamaterials." In ASME 2018 International Design Engineering Technical Conferences and Computers and Information in Engineering Conference. American Society of Mechanical Engineers, 2018. http://dx.doi.org/10.1115/detc2018-85663.

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Topology optimization is being widely employed in designing metamaterial unit cells which can be utilized as core materials for structural components. In this paper, we carried out multi-material topology optimization using orthotropic metamaterials. After topology optimization, the microstructures of the metamaterials are mapped to the resulted irregular domains for each material phase, acting as infill. Different from the existing work, we proposed an alternative way of mapping the metamaterial microstructures to irregular domains by employing the conformal mapping theory. Conformal mapping is an angle-preserving Riemann mapping that preserves the local shape and can efficiently transform a rectangular unit cell to an irregular quadrilateral domain. Each group of metamaterials is bounded by a thin layer of material to guarantee structural connectivity between different microstructures and smooth external boundaries.
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Zhang, Qianyun, Kaveh Barri, Zhong Lin Wang, and Amir H. Alavi. "Digital Information Storage Mechanical Metamaterials." In ASME 2022 Conference on Smart Materials, Adaptive Structures and Intelligent Systems. American Society of Mechanical Engineers, 2022. http://dx.doi.org/10.1115/smasis2022-90268.

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Abstract Information storage is an important functionality to produce a sense-decide-respond loop in active mechanical metamaterial systems. Here, we propose a new class of mechanical metamaterials with self-powered digital information storage capability. In the so-called mechanically-responsive data storage metamaterials, data is incorporated into a set of self-recovering unit cells that form the material lattice. As the metamaterial structure is loaded, the cells in each layer generate electrical signals that are coded as binary bits to represent the stored data. We show how the proposed designs can serve as sequential access memory data storage devices, where the stored data can be accessed in a deformation sequential order under mechanical stimulations. The stiffness of the metamaterial structure can be rationally designed to create either a flexible/soft or hard data storage system. We further discuss the potential of the proposed technology to create low-cost, non-volatile, and long-term storage solutions for data storage applications.
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Wang, Zihan, Ran Zhuang, Weikang Xian, Jiawei Tian, Ying Li, Shikui Chen, and Hongyi Xu. "Phononic Metamaterial Design via Transfer Learning-Based Topology Optimization Framework." In ASME 2022 International Design Engineering Technical Conferences and Computers and Information in Engineering Conference. American Society of Mechanical Engineers, 2022. http://dx.doi.org/10.1115/detc2022-89932.

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Abstract Phononic metamaterials are widely used to attenuate wave propagation. However, designing the structure of phononic metamaterial remains a challenge. In this work, we proposed a transfer learning-based design framework to accelerate the design of phononic metamaterials with wide bandgaps. First, we establish a transfer learning model with convolutional layers. This model leverages the knowledge learned from the structure-elasticity dataset to predict the structure-phononic property relationship. We demonstrate that the transfer learning model achieves good prediction accuracy with limited training data. We also discuss the feasibility of using the structure-elasticity model to benefit the design optimization of phononic metamaterials. Then we propose a transfer learning-based design framework for the topology optimization of cellular metamaterial for optimal phononic properties (bandgap width). Parametric optimization is conducted to find the optimal structure features that lead to the widest bandgap. The structure features are represented by an embedding layer shared by the structure-elasticity and the structure-phononic property models. Next, the corresponding elastic stiffness constants are obtained via the structure-elasticity model. Then topology optimization is employed to generate the metamaterial structural images corresponding to the target elastic stiffness constant values. The effectiveness of the proposed design framework is validated by comparing the performances of design candidates with existing designs.
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Rodrigues, Gustavo Simão, Hans Ingo Weber, and Larissa Driemeier. "Elastic Metamaterial Design to Filter Harmonic Mechanical Wave Propagation." In ASME 2018 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2018. http://dx.doi.org/10.1115/imece2018-87753.

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The metamaterial concept was first oriented to electromagnetic field applications and the main objectives were to develop materials with peculiar properties such as negative dielectric constant, negative magnetic permeability and negative refraction index. Gradually, other areas started using parameters that do not exist in the materials found in nature and, classifying them as metamaterials. So, areas such as acoustics, optics and mechanics opened up space for applications of this innovative “material”. Many efforts for an adequate modeling were made searching also for all kinds of possible applications. One example of application in optics is the use of conformal transformation to design devices with new functionalities from non-homogeneous isotropic dielectric media. The mirages created in the desert are the result of these non-homogeneities. These studies are supposed being helpful to develop invisible cloaks using metamaterials. The present work deals with elastic metamaterial application in mechanical engineering. It is well knowing that metamaterials are able to filter harmonic wave propagation and many works present this capability caused by a bandgap that appears in some range of frequency due to the system’s features. However, it is not very clear how the parameters used for the metamaterials design should be defined. The purpose of this work is to propose a methodology to design an optimized metamaterial component to filter the mechanical wave propagation in a finite chain of masses. It is also in the scope of this work to analyze the borders of the bandgap of the studied chain of masses and how the propagated wave is attenuated along this region.
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Climente, Alfonso, Daniel Torrent, and Jose´ Sa´nchez-Dehesa. "Noise Reduction by Perfect Absorbers Based on Acoustic Metamaterials." In ASME 2011 International Mechanical Engineering Congress and Exposition. ASMEDC, 2011. http://dx.doi.org/10.1115/imece2011-65247.

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We have designed a cylindrical perfect absorber based on acoustic metamaterials. The absorber consists of a metamaterial shell that surrounds a center that dissipates the acoustic energy. The metamaterial shell is designed so that perfectly matches the acoustic impedance of the air background and guides the sound to the center. Numerical simulations are reported about the efficiency of the absorber as a function of the absorbing material employed at the center.
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Yang, Yunfang, and Zhong You. "3D Construction of a Tilted Cuboid Mechanical Metamaterial." In ASME 2018 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2018. http://dx.doi.org/10.1115/imece2018-87050.

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Functional metamaterials are gradually becoming the frontier of scientific research and industrial applications. Among them, reconfigurable mechanical metamaterial with inbuilt motion capability could result in unusual physical properties such as shape tunability and programmable density and stiffness. Inspired by the transformable cuboid structure that was first investigated by Ron Resch, we proposed a tilted cuboid structure that can fold into a 3D configuration. By designing the individual building units, face angles and tessellation pattern, we are able to construct a series of reconfigurable structures with various shape, twist and permeability feature. Based on our approach, a configuration method to build multi-layer metamaterial is proposed, and it can be generalized to other tilted structures with different building units. The volumetric strains of different models are analyzed, and the result shows the metamaterial has a massive deformation ability as the maximum volume can be four times of the packaged volume. The tilted cuboid structure is highly flexible with variable stiffness and permeability, and can be used to develop metamaterials, large deformation devices and kinetic architectures.
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Zhang, Shu, Leilei Yin, and Nicholas Fang. "Design of Acoustic Metamaterials for Super-Resolution Ultrasound Imaging." In ASME 2007 International Mechanical Engineering Congress and Exposition. ASMEDC, 2007. http://dx.doi.org/10.1115/imece2007-44076.

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We report the numerical design and preliminary experiment of 2-D acoustic metamaterials composed of a planar network of subwavelength Helmholtz resonators. The considerably smaller size of the Helmholtz resonator to the corresponding resonant wavelength, allows a compact and light weight design for kilohertz frequency applications. Based on transmission line model to describe the acoustic wave propagation inside such ultrasonic metamaterials, we derived the acoustic parameters such as effective density and compressibility. Extremely large or even negative value of effective density and compressibility can be designed in this acoustic metamaterial. Our simulation demonstrates the focusing and imaging of sound sources through different lenses made of this novel acoustic metamaterial, which may have great potential application in ultrasound imaging. The influences of frequency and source position on the property of the focused image are also investigated.
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Звіти організацій з теми "METAMATERIA"

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Taylor, Antoinette. Novel Terahertz Metamaterials. Office of Scientific and Technical Information (OSTI), November 2013. http://dx.doi.org/10.2172/1107160.

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2

Nemat-Nasser, Siavouche. Tunable Mechanical Metamaterials. Fort Belvoir, VA: Defense Technical Information Center, March 2011. http://dx.doi.org/10.21236/ada547020.

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Stinson, Eric A. Metamaterial Resonant Absorbers for Terahertz Sensing. Fort Belvoir, VA: Defense Technical Information Center, December 2015. http://dx.doi.org/10.21236/ad1009293.

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4

Sriniva, Sridar. Metamaterials for Antenna Technologies. Fort Belvoir, VA: Defense Technical Information Center, September 2006. http://dx.doi.org/10.21236/ada455821.

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Pendry, John B. Metamaterials and Transformation Optics. Fort Belvoir, VA: Defense Technical Information Center, January 2014. http://dx.doi.org/10.21236/ada602461.

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Pendry, John. Metamaterials and Transformation Optics. Fort Belvoir, VA: Defense Technical Information Center, June 2011. http://dx.doi.org/10.21236/ada545171.

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7

Andreev, Andrey D., and Kyle J. Hendricks. Metamaterial Cathodes in Multi-Cavity Magnetrons (Postprint). Fort Belvoir, VA: Defense Technical Information Center, April 2011. http://dx.doi.org/10.21236/ada599592.

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Lee, Youn M. A Test Plan to Measure Metamaterial Performances. Fort Belvoir, VA: Defense Technical Information Center, September 2011. http://dx.doi.org/10.21236/ada551770.

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Krushynska, Anastasiia, Igor Zhilyaev, Nitesh Anerao, Cihat Yilmaz, and Mostafa Ranjbar. 3D-Printed Flexible Wings With Metamaterial Functionalities. Peeref, September 2022. http://dx.doi.org/10.54985/peeref.2209p3789644.

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Dalton, Larry R., and Bruce H. Robinson. Nano-Engineering of Active Metamaterials. Fort Belvoir, VA: Defense Technical Information Center, October 2014. http://dx.doi.org/10.21236/ada610899.

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