24,501 research outputs found
Preparation and Characterization of Waterborne Polyurethaneurea Composed of Dimer Fatty Acid Polyester Polyol
A series of polyurethaneurea (PUU) aqueous dispersions, which were
stable at ambient temperature for more than 1 year, were prepared
with C36-dimer-fatty-acid-based polyester polyol, isophorone
diisocyanate, dimethylol propionic acid, and ethylenediamine. The
particle size of all these PUU (DPU) aqueous dispersions
(<100 nm) was less than that of comparable specimens, that
is, poly-(neopentyl glycol adipate) polyester-polyol-based PUU
(APU) aqueous dispersions, and the polydispersity index was very
narrow (≤1.13). The films prepared with the DPU aqueous dispersions
exhibited excellent waterproof performance, such as low amount of
water absorption (1.3 wt%), and good mechanical properties
(hardness and tensile strength), resulting from the strong
hydrogen bonding in urea carbonyl groups and the perfect ordered
structure of hard segments compared with those prepared with the
APU aqueous dispersions. The surface hydrophobicity of the films
prepared with modified DPU aqueous dispersions, which were
modified with a fluorinated polyacrylate emulsion, was excellent,
as the water contact angle on the surface of such films rose up to
100. The mechanical properties of such modified DPU films were
further enhanced
Battle Against Fluctuating Quantum Noise: Compression-Aided Framework to Enable Robust Quantum Neural Network
Recently, we have been witnessing the scale-up of superconducting quantum
computers; however, the noise of quantum bits (qubits) is still an obstacle for
real-world applications to leveraging the power of quantum computing. Although
there exist error mitigation or error-aware designs for quantum applications,
the inherent fluctuation of noise (a.k.a., instability) can easily collapse the
performance of error-aware designs. What's worse, users can even not be aware
of the performance degradation caused by the change in noise. To address both
issues, in this paper we use Quantum Neural Network (QNN) as a vehicle to
present a novel compression-aided framework, namely QuCAD, which will adapt a
trained QNN to fluctuating quantum noise. In addition, with the historical
calibration (noise) data, our framework will build a model repository offline,
which will significantly reduce the optimization time in the online adaption
process. Emulation results on an earthquake detection dataset show that QuCAD
can achieve 14.91% accuracy gain on average in 146 days over a noise-aware
training approach. For the execution on a 7-qubit IBM quantum processor,
IBM-Jakarta, QuCAD can consistently achieve 12.52% accuracy gain on earthquake
detection
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