Performance of superconducting single-photon detectors based on resistive hotspot formation in nanostripes upon optical photon absorption depends strongly on the critical current density J(C) of the fabricated nanostr...
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ISBN:
(纸本)9781628416251
Performance of superconducting single-photon detectors based on resistive hotspot formation in nanostripes upon optical photon absorption depends strongly on the critical current density J(C) of the fabricated nanostructure. Utilization of an ultrathin, weak-ferromagnet cap layer on the top of a superconducting film enhances of the structure's J(C) due to an extra flux pinning. We have fabricated a number of both NbN/NiCu and NbTiN/NiCu superconductor/ferromagnet (S/F) ultrathin bilayers and microbridges. NbN and NbTiN underlayers with thicknesses varying from 4 to 7 nm were grown using dc-magnetron sputtering on chemically cleaned sapphire single-crystal substrates. After rapid thermal annealing at high temperatures, the S films were coated with Ni0.54Cu0.46 overlayers with thicknesses of about 6 nm, using co-sputtering. Compositions of the deposited films were confirmed by EDX spectroscopy analysis, while TEM studies demonstrated excellent epitaxial quality of our S layers with similar to 2-nm-thick F/S transition layer and atomically-sharp S/substrate interface. Magnetic properties of bilayers were studied using both the SQUID and Vibrating Sample Magnetometer techniques in low and high magnetic fields. Low-temperature tests confirmed that in all cases NiCu films were ferromagnetic with the Curie temperature of above 30 K. Below the bilayer critical temperature of approx. 12-13 K, the structures were fully proximitized with the strong superconducting signal. For superconducting transport properties characterization, we used bilayers patterned into 40-mu m-long microbridges with the width varying from 0.4 mu m to 2 mu m. The same S/F nanostructures were also used to study their superconducting fluctuations. The temperature dependence of magnetoresistance demonstrated highly 2-dimensional character with an unusual negative region that extended almost to room temperature. In the S/F sample, the fluctuations were observed to be substantially below theoretical expecta
Denial-of-service (DoS) and distributed denial-of-service (DDoS) attacks are blatant attempts to prevent legitimate users from reaching a service or from using the service they already are using. DDoS attacks are poss...
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The proceedings contain 20 papers. The topics discussed include: design and implementation of convolutional neural network accelerator with variable layer-by-layer debugging;a wide residual network for sentiment class...
ISBN:
(纸本)9781450364737
The proceedings contain 20 papers. The topics discussed include: design and implementation of convolutional neural network accelerator with variable layer-by-layer debugging;a wide residual network for sentiment classification;click-through rate estimates based on deep learning;a deep learning image recognition framework accelerator based parallel computing;attention-based neural network for short-text question answering;Deep Lang - a language learning app empowered by deep learning;using improved restricted Boltzmann machines for drug-disease prediction;comparative study of outlier detection algorithms for machine learning;improvement of pruning method for convolution neural network compression;and airport passenger flow forecast based on the wavelet neural network model.
Nanometer CeO2 with the mean size of 15 nm is prepared by sol-gel method, and the CO catalytic oxidation activity of Pd-Cu catalysts with three kinds of CeO2 supports was studied. The results show that nanometer CeO2 ...
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Nanometer CeO2 with the mean size of 15 nm is prepared by sol-gel method, and the CO catalytic oxidation activity of Pd-Cu catalysts with three kinds of CeO2 supports was studied. The results show that nanometer CeO2 supported Pd-Cu catalyst gives highest activity for CO oxidation. It can maintain CO complete conversion at about 40°C.
In Intuitionistic fuzzy sets(IFSs), experts assign both membership value and non-membership value to each fuzzy element x with a certain degree of hesitation. The hesitancy in the opinion of the experts appear due to ...
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ISBN:
(纸本)9781467374286
In Intuitionistic fuzzy sets(IFSs), experts assign both membership value and non-membership value to each fuzzy element x with a certain degree of hesitation. The hesitancy in the opinion of the experts appear due to incomplete information available regarding x. Therefore, precise estimation of its both membership value and non-membership value becomes highly difficult. Hence, there is a high chance that both membership value and the non-membership value assigned to x by the expert may not be absolutely correct. So, whenever we try to measure similarity between the IFSs using the various distance measures involving all the components of IFSs like membership value, non-membership value together with hesitation, then we often notice that all of them fails to describe the underlying situation completely. Therefore, the similarity measures derived from these distance measures also fails to produce good results. So, we introduce a new similarity measure by properly defining a similarity degree through the result established in this paper. The similarity measure has a central role in developing a modified lambda-cutting algorithm for clustering. Here we also establish the efficacy of our modified lambda-cutting algorithm while implementing it on a real world data set.
With the development of power systems, the harmonic problem has become more and more prominent. In the application of active power filters, the traditional ip-iq algorithm can only detect total harmonics and cannot ob...
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ISBN:
(数字)9798350391329
ISBN:
(纸本)9798350391336
With the development of power systems, the harmonic problem has become more and more prominent. In the application of active power filters, the traditional ip-iq algorithm can only detect total harmonics and cannot obtain specific harmonics. To address this problem, this paper proposes an improved ip-iq algorithm for active power filters. This algorithm is improved based on the difference in separation objects of harmonic detection algorithms. It can convert specific harmonics into DC components. After low-pass filtering and inverse transformation, the specific harmonic components in the original three-phase current can be obtained. Compared with the traditional algorithm, mainly by modifying the transformation matrix $C_{x}$ and its inverse matrix ${C_{x}}^{-1}$ according to the difference between positive and negative sequence harmonics, it is simple to implement in active power filters and does not require complex calculations, greatly expanding the harmonic detection range and accurately detecting specified harmonics. A simulation model is constructed using Matlab/Simulink software to detect the 5th and 7th harmonics under two conditions of different harmonic contents in grid current. The results show that in the application of active power filters, when the content of specified harmonics is large, the detection result is more accurate. When the content is small, although there may be errors due to interference from other harmonics, it is within an acceptable range. Thus, the feasibility and effectiveness of the improved ip-iq algorithm in detecting specific harmonics in active power filters are verified.
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