New aircraft designs increasingly contain more components made from polymer matrix composites, in both primary and secondary roles. This demands new monitoring techniques that emphasize the role played by polymer matr...
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New aircraft designs increasingly contain more components made from polymer matrix composites, in both primary and secondary roles. This demands new monitoring techniques that emphasize the role played by polymer matrix degradation in the failure of these parts. The polymer matrix does not take significant load in tension but must transfer shear load. The present work investigates changes in surface chemistry due to accelerated thermo-oxidative aging on a bismaleimide (BMI) laminate system reinforced with woven glass fiber. BMI is used for high temperature applications up to 230 °C. Samples are isothermally aged at various temperatures whose selection is guided by degradation steps revealed by thermo-gravimetric analysis. Permittivity of aged samples is measured as a function of frequency from 200 Hz to 2 MHz, using a parallel-plate electrode design. Results are compared with measured interlaminar shear stress to assess the suitability of capacitive sensing as a method for nondestructive monitoring of thermo-oxidative aging in this material system.
An integrated CMOS-compatible multiple-wavelength optical source is exploited for photonic implementation of a quadrature hybrid RF coupler based on multi-tap transversal filtering scheme. Four octave bandwidth with a...
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Electromigration experiments have been carried out on simple Cu dual-damascene interconnect tree structures consisting of straight via-to-via (or contact-to-contact) lines with an extra via in the middle of the line. ...
Electromigration experiments have been carried out on simple Cu dual-damascene interconnect tree structures consisting of straight via-to-via (or contact-to-contact) lines with an extra via in the middle of the line. As with Al-based interconnects, the reliability of a segment in this tree strongly depends on the stress conditions of the connected segment. Beyond this, there are important differences in the results obtained under similar test conditions for Al-based and Cu-based interconnect trees. These differences are thought to be associated with variations in the architectural schemes of the two metallizations. The absence of a conducting electromigrationresistant overlayer in Cu technology, and the possibility of liner rupture at stressed vias lead to significant differences in tree reliabilities in Cu compared to Al.
(Ag, CU) ( mathbf{In}, mathbf{Ga}) mathbf{Se}-{ boldsymbol{2}}-based solar cells have achieved high collection efficiencies, but defects still limit efficiencies well below the theoretical limit. The near-conduction b...
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We address the problem of efficient circuit switching in wide area networks. The solution provided is based on finding optimal routes for lightpaths and semilightpaths. A lightpath is a fully optical transmission path...
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We address the problem of efficient circuit switching in wide area networks. The solution provided is based on finding optimal routes for lightpaths and semilightpaths. A lightpath is a fully optical transmission path, while a semilightpath is a transmission path constructed by chaining several lightpaths together, using wavelength conversion at their junctions. The problem thus is to find an optimal lightpath/semilightpath in the network in terms of the cost of wavelength conversion and the cost of using the wavelengths on links. We first present fast, efficient algorithms both for the general problem and for a natural restricted version. The new algorithms outperform earlier work, providing time improvements amounting to an almost linear time factor in most cases. Also, all our algorithms can be implemented on the network in a distributed way.
We show a self-driven indium selenide (InSe) p-n heterojunction photodetector with a threefold increase in responsivity at 980 nm over a photoconductor detector based on p- or n-doped regions.
ISBN:
(数字)9781957171050
ISBN:
(纸本)9781665466660
We show a self-driven indium selenide (InSe) p-n heterojunction photodetector with a threefold increase in responsivity at 980 nm over a photoconductor detector based on p- or n-doped regions.
Two series of [Ru10/Cox)]12 and [Ru6/Cr3/Cox)]12 x=16-60 easy-plane anisotropy multilayers (all thicknesses in Å), prepared by sputter deposition, are studied by cavity FMR. The acoustic modes are excited by sett...
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A stroke, also known as brain attack, occurs when blood supply to your brain is interrupted. Primary prevention relies on prompt prediction of a stroke. While currently there are several clinical risk scores, machine ...
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We propose and experimentally demonstrate a reconfigurable radiofrequency (RF)-photonic sensor network comprised of three entangled sensor nodes to increase the precision of parameter estimation in networked RF sensin...
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Bravais lattices are the most fundamental building blocks of crystallography. They are classified into groups according to their translational, rotational, and inversion symmetries. In computational analysis of Bravai...
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