Convolutional neural networks (CNNs) have been widely used in image recognition and processing tasks. Memristor-based CNNs accumulate the advantages of emerging memristive devices, such as nanometer ...critical dimensions, low power consumption, and functional similarity to biological synapses. Most studies on memristor-based CNNs use either software models of memristors for simulation analysis or full hardware CNN realization. Here, we propose a hybrid CNN, consisting of a hardware fixed pre-trained and explainable feature extractor and a trainable software classifier. The hardware part was realized on passive crossbar arrays of memristors based on nanocomposite (Co-Fe-B)x(LiNbO3)100−x structures. The constructed 2-kernel CNN was able to classify the binarized Fashion-MNIST dataset with ~ 84% accuracy. The performance of the hybrid CNN is comparable to the other reported memristor-based systems, while the number of trainable parameters for the hybrid CNN is substantially lower. Moreover, the hybrid CNN is robust to the variations in the memristive characteristics: dispersion of 20% leads to only a 3% accuracy decrease. The obtained results pave the way for the efficient and reliable realization of neural networks based on partially unreliable analog elements.
Convolutional neural networks (CNNs) have been widely used in image recognition and processing tasks. Memristor-based CNNs accumulate the advantages of emerging memristive devices, such as nanometer ...critical dimensions, low power consumption, and functional similarity to biological synapses. Most studies on memristor-based CNNs use either software models of memristors for simulation analysis or full hardware CNN realization. Here, we propose a hybrid CNN, consisting of a hardware fixed pre-trained and explainable feature extractor and a trainable software classifier. The hardware part was realized on passive crossbar arrays of memristors based on nanocomposite (Co-Fe-B)sub.x(LiNbOsub.3)sub.100−x structures. The constructed 2-kernel CNN was able to classify the binarized Fashion-MNIST dataset with ~ 84% accuracy. The performance of the hybrid CNN is comparable to the other reported memristor-based systems, while the number of trainable parameters for the hybrid CNN is substantially lower. Moreover, the hybrid CNN is robust to the variations in the memristive characteristics: dispersion of 20% leads to only a 3% accuracy decrease. The obtained results pave the way for the efficient and reliable realization of neural networks based on partially unreliable analog elements.
USE AMINOMETHYLTERPENOPHENOLS IN EPOXY RESINS Vaseneva, Irina N.; Sitnikov, Petr A.; Belykh, Anna G. ...
IZVESTIYA VYSSHIKH UCHEBNYKH ZAVEDENIY KHIMIYA KHIMICHESKAYA TEKHNOLOGIYA,
06/2018, Volume:
61, Issue:
7
Journal Article
Peer reviewed
Open access
Aminomethylterpenophenols differing in the position of the amino group and its alkyl substituents have been studied as catalysts in the preparation of epoxy resins and stabilizers for their thermal ...degradation to produce materials with high physicomechanical and thermo-oxidative characteristics. The heat effects of anionic polymerization of an epoxy oligomer in the presence of 2,4,6-tris (dimethylaminomethyl) phenol (UP-606/2), 2-dibutylaminomethyl-6-isobornyl-4-methylphenol (I), 2-isobornyl-4-dimethylaminomethyl-6-methylphenol (II), 2-dimethylaminomethyl-6-isobornyl-4-methylphenol (III), 2,6-diisobornyl-4-dimethylaminomethylphenol (IV) were studied using DSC method. The DSC curves exhibit exothermic peaks, which relate to the polymerization of the oligomer. It is shown that terpenophenols with a dimethylaminomethyl group in the para position relative to the OH group have the highest activity. Heat effects were studied in the polycondensation of an epoxy oligomer with iso-MTHPA in the presence of aminomethylterpenophenols as catalysts. It has been shown that compounds II and IV reduce the temperature of the onset of the reaction by 62 and 8 °C, respectively, compared with the commercially available UP-606/2, and in addition the exothermic effect (Q) is increased by 10 J/g and the energy activation (Ea) by 21 kJ/mol of polycondensation reaction with compound II. Aminomethylterpenephenols improve the resistance of the epoxy resin to thermal aging, in which a reduction in strength from 9 to 23% is observed, in the case of UP-606/2, the strength is reduced by 30%. It has been established that the activation energies of the thermooxidative degradation of resins obtained by introducing compounds II and IV are higher by 10 and 40%, respectively, than when using UP-606/2. Strength characteristics of a polymer matrix containing para-dimethylaminomethyl terpenophenol are higher by 25% than with the use of an industrial analogue - UP-606/2 (2,4,6-tris (dimethylaminomethyl) phenol). It was found that the resins obtained with the use of the catalysts 2-isobornyl-4-dimethylaminomethyl-6-methylphenol and 2,6-diisobornyl-4-dimethylaminomethylphenol have the greatest resistance to thermal oxidation.For citation:Vaseneva I.N., Sitnikov P.A., Belykh A.G., Chukicheva I.Yu., Buravlev E.V., Kutchin A.V. Use aminomethylterpenophenols in epoxy resins. Izv. Vyssh. Uchebn. Zaved. Khim. Khim. Tekhnol. 2018. V. 61. N 7. P. 113-120
This article describes the peculiarities of the phase composition and the electronic structure of composite Al0.75Si0.25 fi lms on a silicon substrate Si(100) obtained by magnetron and ion-beam ...sputtering. As a result of magnetron sputtering, Si nanocrystals with the sizes of ~25nm and metastable ordered solid solution Al3Si are formed in an Al matrix. Al3Si is characterized by a Рm3m cubic crystal structure with a primitive cell parameter a = 4.085 Å. The fi lms obtained by ion-beam sputtering contain only the ordered solid solution Al3Si. The Al3Si phase formation is accompanied by changes of the Al 3s-states density distribution. There is a linear dependence of the density-of-states distribution from energy instead of a parabolic dependence in the lower and middle part of the valence band (as in the case of pure metal). A similar effect was observed for Si 3s-states. In addition, the interaction between Al and Si atoms leads to the decrease of Al 3s-states density near the Fermi level. This is a result of electrons transitioning from Al atoms to the more electronegative silicon atoms. In case of magnetron fi lms, selective etching of aluminium leads to the formation of nanoporous sponge structure. And the selective etching of ion-beam fi lms does not cause well-developed morphology formation. Subsequent pulsed photon annealing (PPA) of the ion-beam fi lms (at 145–216 J/cm2) leads to the partial disintegration of Al3Si phase with the formation of metallic aluminium and silicon nanocrystals. The size of Si nanoparticles depends on PPA regimen and equals to 50–100 nm. Subsequent etching of the sample subjected to PPA leads to the formation of a nanoporous structure.
Background: Warfarin is still, in some cases, the only medication to prevent thromboembolic complications. Warfarin intake imposes regular INR monitoring, which can be performed domiciliary. ...Currently, in the Russian market, there are two models of automatic portable blood coagulometers: CoaguChek XS (Germany) and qLabs ElectroMeter (China). The main problem of portable coagulometers is their high cost and high cost of operation, which the majority of patients cannot afford. To explore the demand for development of a Russian coagulometer with a more affordable price, a questionnaire survey was carried out among the patients who needed this device. Methods and Results: We surveyed 70 patients taking Warfarin, with 5 years duration paroxysmal, persistent/or stable AF of nonvalvular etiology, having >2 CHADS-VASc score for thrombembolia risk assessment and <3 HAS-BLED score for hemorrhage risk assessment. According to the survey results, 7 (10%) patients had portable coagulometers, including 3 persons with CoaguChek XS and 4 persons with Micropoint qLabs ElectroMeter. Among these patients, there were 4 persons who continued regular INR monitoring domiciliary, while 3 patients had financial difficulties in getting testing strips. At the same time, 14 (20%) patients were not aware of the possibility of domiciliary INR monitoring. As it turned out, those patients who received regular INR monitoring domiciliary with a portable coagulometer, or at their local polyclinics, had neither ischemic strokes nor hemorrhages within a period of five years. Conclusion: It is critical to develop and manufacture a domestic equivalent of a portable coagulometer and testing strips for household use at a more affordable price.
In Russia the developments on composite transmission line supports are actively carried out and pilot line sections are put into operation. However, for mass introduction it is necessary to create a ...single universal platform, which could be successfully used not only in linear fittings of power transmission lines, but also in other structures. The purpose of this paper is practical determination of the possibility of using press-composite materials produced by LLC "TatneftPresscomposite" for 6(10) kV overhead line traverses. In the article the methodology of calculation of constructive solutions for replacement of typical constructions of crossbeams from press-composite materials is given, unique data on mechanical and electrical strength of constructive elements are experimentally obtained. The data obtained in the course of researches testify to the expediency of application of this methodology in the design of such structural solutions, as well as the possibility of application of ready-made elements produced by LLC "Tatneft-Presscomposite" for creation of 6(10) kV overhead power line beams.
The paper deals with the theoretical model of a so-called apokamp discharge. It is known as unique atmospheric pressure plasmajet generated without natural or artificial convection from the bending ...region of a pulsed- periodic gas discharge channel of a specific configuration. Based on the simplified oxygen plasma-chemical model here we give a theoretical explanation of the apokamp phenomenon for the first time. It was shown that the apokamp is a stable plasma jet having physical nature of a positive streamer, it arises when some specific electrodynamic conditions are satisfied.
It is not by chance that the second article presented for the readers' scrutiny is devoted to regional budget-tax problems that are usually explored at the end of a series. The authors are convinced ...that financial mechanisms of regional policy are today a most powerful lever in the actual formulation of that policy. This is a case where the urgency of the problem predetermines the logic of its presentation.
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