bluuebunny/crossref_metadata_2025 huggingface dataset:
Tailoring exchange bias in reentrant spin glass by ferromagnetic cluster size engineering
Authors: Tian Fanghua , Ke Xiaoqin , Cao Kaiyan , Wang Dingchen , Zhao Qizhong , Li Jianing , Dai Zhiyong , Wang Dong , Zhang Yin , Zhou Chao , Wang Yu , Zuo Wenliang , Fang Minxia , Yang Sen
Published: January 2021

Many properties of materials exhibit a heavy dependency on the domain/grain size due to the change in interface density. Here, we show that in bulk Ni2Mn1+xGa1−x alloys (0.4 < x < 0.7), the exchange bias (EB) effect appears in the reentrant spin glass region and the magnitude of exchange bias (HEB) depends on the size of the ferromagnetic (FM) cluster in the antiferromagnetic (AFM) matrix. It was found that HEB first increases and then deceases as the size of the FM cluster decreases, which shows a non-monotonical relationship with the FM cluster size, and the relationship is similar to the grain size dependence of material properties such as the mechanical strength of metals and dielectric permittivity of ferroelectric ceramics. Further phase field simulation results repeat this phenomenon and illustrate that the change in EB can be attributed to the change in density of the FM/AFM interface, which provides a regulatable extra bias field through the Dzyaloshinskii–Moriya interaction. This work provides a method to tune HEB in bulk materials and reveals the mechanism of the dependency of EB on the FM cluster size, which could guide the design of bulk exchange-bias materials.
High efficiency blue InGaN microcavity light-emitting diode with a 205 nm ultra-short cavity
Authors: Back Joonho , Wong Matthew S. , DenBaars Steven P. , Weisbuch Claude , Nakamura Shuji
Published: January 2021

High-efficiency blue InGaN-based semipolar (20-2-1) ultra-short microcavity light-emitting diodes (MC-LEDs) with a cavity length of 205 nm were demonstrated. A peak external quantum efficiency (EQE) of 7.3%, the value of which is almost the same as 10% of conventional c-plane micrometer-sized microlight-emitting diodes with a device thickness of ∼5 μm grown on the sapphire substrate, was achieved. The emission wavelength is 431 nm at the current density of 297 A/cm2. In order to obtain high-efficiency MC-LEDs, a sidewall treatment was performed by using buffered hydrofluoric acid and phosphoric acid (H3PO4) to remove the dry etching residue and the surface damage. The demonstration of MC-LEDs with a high EQE and a single mode emission should pave the way for the application to display and others.
Switching performance comparison between conventional SOT and STT-SOT write schemes with effect of shape deformation
Authors: Byun J. , Kang D. H. , Shin M.
Published: January 2021

We demonstrate the effect of shape deformation in spin–orbit torque magnetoresistive random access memory (SOT-MRAM) based on micromagnetic simulation by generating 1000 randomly deformed samples using the exponentially decaying autocorrelation function. The conventional in-plane magnetic field-assisted SOT write scheme and the recently proposed spin-transfer torque-spin-orbit torque (STT-SOT) hybrid write scheme were simulated and compared with the effect of the Gilbert damping constant (α) considered in the presence and the absence of the Dzyaloshinskii–Moriya interaction (DMI). We found that shape deformation of the MTJ can result in write failure or degradation of the switching time. To compensate the device-to-device performance variation induced by the shape deformation, the condition of high α and the presence of the DMI is desired for the magnetic field-assisted write scheme. The STT-SOT shows slight improvement in the switching performance for larger α and the presence of DMI while it retains 100% switching probability even with small α regardless of the DMI.
Prospects for multimodal visualisation of biological tissues using fluorescence imaging
Authors: Tuchina D.K. , Meerovich I.G. , Sindeeva O.A. , Zherdeva V.V. , Kazachkina N.I. , Solov’ev I.D. , Savitsky A.P. , Bogdanov A.A. , Tuchin V.V.
Published: January 2021

We investigate skin optical clearing in laboratory animals ex vivo and in vivo by means of low-molecular-weight paramagnetic contrast agents used in magnetic resonance imaging (MRI) and a radiopaque agent used in computed tomography (CT) to increase the sounding depth and image contrast in the methods of fluorescence laser imaging and optical coherence tomography (OCT). The diffusion coefficients of the MRI agents Gadovist®, Magnevist®, and Dotarem®, which are widely used in medicine, and the Visipaque® CT agent in ex vivo mouse skin, are determined from the collimated transmission spectra. MRI agents Gadovist® and Magnevist® provide the greatest optical clearing (optical transmission) of the skin, which allowed: 1) an almost 19-fold increase in transmission at 540 nm and a 7 – 8-fold increase in transmission in the NIR region from 750 to 900 nm; 2) a noticeable improvement in OCT images of skin architecture; and 3) a 5-fold increase in the ratio of fluorescence intensity to background using TagRFP-red fluorescent marker protein expressed in a tumour, after application to the skin of animals in vivo for 15 min. The obtained results are important for multimodal imaging of tumours, namely, when combining laser fluorescence and OCT methods with MRI and CT, since the contrast agents under study can simultaneously enhance the contrast of several imaging methods.
Deubiquitinating enzyme amino acid profiling reveals a class of ubiquitin esterases
Authors: De Cesare Virginia , Carbajo Lopez Daniel , Mabbitt Peter D. , Fletcher Adam J. , Soetens Mathieu , Antico Odetta , Wood Nicola T. , Virdee Satpal
Published: January 2021

Significance

Ubiquitination involves the covalent attachment of the protein ubiquitin to substrates. It can be reversed by the action of deubiquitinating enzymes (DUBs), thereby providing an important layer of regulation. Originally believed to be restricted to lysine residues, it is emerging that additional amino acids, including serine, threonine and cysteine, are also modified. It remains unknown which DUBs might target these unusual sites for deubiquitination. Herein, we develop representative model substrates and screen 53 DUBs for non-lysine activity, thereby providing important insights into DUB function. Strikingly, we find that a poorly studied DUB class has potent and highly selective serine/threonine activity. These findings suggest that non-lysine ubiquitination rivals the regulatory sophistication of its conventional counterpart and might serve distinct cellular functions.
Harnessing ultraconfined graphene plasmons to probe the electrodynamics of superconductors
Authors: Costa A. T. , Gonçalves P. A. D. , Basov D. N. , Koppens Frank H. L. , Mortensen N. Asger , Peres N. M. R.
Published: January 2021

Significance

Superconductivity and plasmonics constitute two extremely vibrant research topics, although with often nonoverlapping research communities. Here, we bridge these two active research fields by showing that graphene plasmons’ unprecedented light localization into nanometric scales can be exploited to probe the electrodynamics (including collective excitations) of superconductors. Our findings are important both from a fundamental standpoint, representing a paradigm shift (i.e., probing of Higgs modes by light fields), and also for future explorations interfacing nanophotonics with strongly correlated matter, which holds prospects for fostering additional concepts in emerging quantum technologies.
Diagenetic formation of uranium-silica polymers in lake sediments over 3,300 years
Authors: Lefebvre Pierre , Gourgiotis Alkiviadis , Mangeret Arnaud , Sabatier Pierre , Le Pape Pierre , Diez Olivier , Louvat Pascale , Menguy Nicolas , Merrot Pauline , Baya Camille , Zebracki Mathilde , Blanchart Pascale , Malet Emmanuel , Jézéquel Didier , Reyss Jean-Louis , Bargar John R. , Gaillardet Jérôme , Cazala Charlotte , Morin Guillaume
Published: January 2021

Significance

Understanding the long-term fate of widespread noncrystalline uranium (U) species is critical to improving our knowledge of U biogeochemistry and U-contaminated environments. We use naturally U-enriched lake sediments that have been deposited for thousands of years as an analogue for the progressive evolution of contaminated environments, in order to uncover if noncrystalline species may evolve into more resistant crystalline phases. We combine multidisciplinary tools including U isotope ratio and speciation techniques to describe a mineralogical transformation where organic-bound U evolves into polymeric and nanocrystalline uranium-silica phases that are still easily remobilized even 3,300 y after their deposition. These findings bring an interpretation that illuminates an active debate on uranium mobility in the environment.
Langue de bois, or, discourse in defense of an offshore financial center
Authors: Weeks Samuel
Published: January 2021

This article brings together trends in Critical Discourse Analysis dating from the 1980s – which examine how
language use and ideologies (re)produce social inequality – with current research in the social sciences on neoliberalism and
other emerging politico-economic formations. The article addresses such a problematic with an empirical case: the language
strategies, dubbed langue de bois, that people affiliated with Luxembourg’s offshore financial center employ to
justify their practices. The contribution herein surveys the political rationality of the country’s financial center by analyzing
the langue de bois that its representatives and boosters use. These language strategies, furthermore, enable
Luxembourg’s finance elites to socialize the domestic public’s understanding of their activities.
‘We need to talk about the hegemony of the left’
Authors: Boukala Salomi
Published: January 2021

This article seeks to explore the discursive rediscovery of the left menace and the ideological relevance between the far right and the right wing in Greece in times of political turmoil. Drawing on some historical aspects of modern Greece, first, I intend to explain the resurgence of Greece’s divided past. By emphasising references to Gramsci and the ‘hegemony of the left’, the article investigates the discursive construction of ingroups and outgroups on the basis of haunted memories of modern Greek history. By synthesising the Discourse Historical Approach and the concept of Aristotelian topos, I explicate how Gramsci has been re-utilised in an extreme right context by Greek far-right figures in order to stigmatise their ideological opponents. In a second step, my aim is to study the normalisation of political enmity by highlighting far-right discourses’ resemblance to New Democracy’s members’ rhetoric through references to Greek culture and economic imaginaries.
Use of antimicrobial alternatives in broilers and their impacts on health and productive performance
Authors: Redondo Leandro M. , Fernandez-Miyakawa Mariano E.
Published: January 2021

Antimicrobials are the keystone of therapy for bacterial infectious diseases. The One Health approach recognizes that the health of humans, animals, and the environment are intricately connected, where the use of antimicrobials in animals select for resistant bacteria which carries resistant genetic elements that can be transmitted from animals to humans. Therefore, antimicrobials use should be limited to treat sick animals. The removal of antimicrobials as growth promoters from animal diets is a growing and irreversible process that led to develop, select, and use cost and effective alternatives in poultry production. The most popular alternatives widely used in several regions of the world include metals, enzymes, organic acids, probiotics, prebiotics, synbiotics, phytochemicals and combinations of them. The expected outcomes in health and productive performances of poultry chickens can be achieved if those antimicrobial alternatives are able to control some factors that influence gut health and productivity. The present review focuses on the impact of most widespread alternatives used for growth promotion on microbiota, immune system, and oxidative status.
Combined relationship of physical inactivity and sedentary behaviour with the prevalence of noncommunicable chronic diseases: data from 52,675 Brazilian adults and elderly
Authors: Bertuol Cecília , Tozetto Willen Remon , Streb Anne Ribeiro , Del Duca Giovani Firpo
Published: January 2021

This paper aims to verify the association between the combined relationship of physical inactivity and sedentary behaviour (SB) at leisure‐time and the prevalence of noncommunicable chronic diseases (NCDs) in Brazilian adults and elderly. This is a cross‐sectional study, derived from the VIGITEL system, with individuals ≥18 years old (n = 52,675). The presence of NCDs (diabetes, hypertension, and obesity) and the independent variables were defined by self‐report. Binary logistic regression was used. While adults with the presence of, at least, one risky behaviour had a higher odds to have obesity (OR active + high SB: 1.25; 95%CI: 1.01;1.54; OR inactive + low SB: 1.47; 95%CI: 1.25;1.73; OR inactive + high SB: 1.77; 95%CI: 1.47;2.12), the elderly had an increased risk for this outcome only when classified as inactive (OR inactive + low SB: 1.43; 95%CI: 1.17;1.75; OR inactive + high SB: 1.87; 95%CI: 1.47;2.38). Inactive adults with low SB were more likely to have diabetes (OR inactive + low SB: 1.31; 95%CI: 1.00;1.71) and hypertension (OR inactive + low SB: 1.26; 95%CI: 1.08;1.46), while physical inactivity was again more strongly associated with these outcomes in the elderly, for diabetes (OR inactive + low SB: 1.23; 95%CI: 1.02;1.48; OR inactive + high SB: 1.75; 95%CI: 1.39;2.19), and hypertension (OR inactive + low SB: 1.22; 95%CI: 1.05;1.41; OR inactive + high SB: 1.60; 95%CI: 1.33;1.94) Both leisure‐time behaviours carry a high risk of the prevalence of different NCDs, however, physical inactivity, isolated or combined, showed a greater association with the evaluated outcomes.

Highlights

This cross‐national survey included representative sample of people ≥18 years old.

Adults with at least one evident risky behavior had a higher chance of obesity.

Inactive adults with low sedentary behavior had higher chances for diabetes and hypertension.

Physical inactivity was more strongly associated with all diseases in the elderly.
Enhanced magnetic Lorentz force second harmonic generation originating from a double-resonances plasmonic metasurface
Authors: Yang Guanghui , Li Zixiang , Kang Qianlong , Guo Kai , Zhang Han , Guo Zhongyi
Published: January 2021

Artificial second harmonic generation (SHG) based on magnetic Lorentz force has attracted abundant attention from researchers because of the initial breakthrough in physics. It is still a challenging task to boost this type of SHG emission due to the relative lower efficiency and the specific polarization of artificial SHG. Here, we demonstrate an effective way to enhance the magnetic Lorentz force-based SHG in a double-resonances plasmonic metasurface. The design of our method is twofold: firstly, a dark resonance at fundamental frequency and a bright resonance at second harmonic frequency (SHF); secondly, polarization consistency between the bright resonance and the SHF signal. The results demonstrate that the SHF conversion efficiency of this mode-matching plasmonic metasurface can reach 1.4 × 10−9, which is enhanced by a factor of 5.17 compared to the case without the mode-matching mechanism. This high efficiency and free design of a plasmonic metasurface offer a promising way for the applications of nonlinear optics.
Image-level supervised segmentation for human organs with confidence cues
Authors: Chen Zhang , Tian Zhiqiang , Zheng Yaoyue , Si Xiangyu , Qin Xulei , Shi Zhong , Zheng Shuai
Published: January 2021

Image segmentation for human organs is an important task for the diagnosis and treatment of diseases. Current deep learning-based methods are fully supervised and need pixel-level labels. Since the medical images are highly specialized and complex, the work of delineating pixel-level segmentation masks is very time-consuming. Weakly supervised methods are then chosen to lighten the workload, which only needs physicians to determine whether an image contains the organ regions of interest. These weakly supervised methods have a common drawback, in that they do not incorporate prior knowledge that alleviates the lack of pixel-level information for segmentation. In this work, we propose a weakly supervised method based on prior knowledge for the segmentation of human organs. The proposed method was validated on three data sets of human organ segmentation. Experimental results show that the proposed image-level supervised segmentation method outperforms several state-of-the-art methods.
Modeling complex particles phase space with GAN for Monte Carlo SPECT simulations: a proof of concept
Authors: Sarrut D , Etxebeste A , Krah N , Létang JM
Published: January 2021

A method is proposed to model by a generative adversarial network the distribution of particles exiting a patient during Monte Carlo simulation of emission tomography imaging devices. The resulting compact neural network is then able to generate particles exiting the patient, going towards the detectors, avoiding costly particle tracking within the patient. As a proof of concept, the method is evaluated for single photon emission computed tomography (SPECT) imaging and combined with another neural network modeling the detector response function (ARF-nn). A complete rotating SPECT acquisition can be simulated with reduced computation time compared to conventional Monte Carlo simulation. It also allows the user to perform simulations with several imaging systems or parameters, which is useful for imaging system design.
Advanced electromagnetic modeling of large-scale high-temperature superconductor systems based on H and T-A formulations
Authors: Berrospe-Juarez Edgar , Trillaud Frederic , Zermeño Víctor M R , Grilli Francesco
Published: January 2021

The development of the high-temperature superconductors (HTS) has allowed the emergence of diverse superconductor devices. Some of these devices, like wind power generators and high-field magnets, are classified as large-scale HTS systems, because they are made of several hundreds or thousands of turns of conductors. The electromagnetic analysis of such systems cannot be addressed by means of the available analytical models. The finite-element method has been extensively used to solve the H formulation of the Maxwell’s equations, thus far with great success. Nevertheless, its application to large scale HTS systems is still hindered by excessive computational load. The recently proposed T-A formulation has allowed building more efficient models for systems made of HTS tapes. Both formulations have been successfully applied in conjunction with the homogenization and multi-scaling methods, these advanced methods allow reducing the required computational resources. A new advanced method, called densification, is proposed here. The most important contribution of this article is the comprehensive comparison of the strategies emerged from the combined use of the two formulations and the three advanced methods.
Scanning Raman spectroscopy for inline characterization of 2G-HTS conductors
Authors: Castaneda Nathaly , Majkic Goran , Robles Francisco C
Published: January 2021

We report on a feasibility study of using Raman micro-spectroscopy as a characterization method for quality control of

REB

a

2

C

u

3

O

7
−
δ

(REBCO, rare-earth barium copper oxide) coated conductors (CC). Fragments of long REBCO tape deposited using advanced metal organic chemical vapor deposition with dropouts in critical current (I
c) were analyzed implementing Raman spectroscopy in area scan (map) and linear scan modes, in order to evaluate the level of information obtainable with the technique. The areal maps have been found to provide detailed information on the spatial distribution of the sample quality, providing maps of both intensity and wavelength shift characteristic of Raman-active peaks. The maps readily identify defective regions ranging from completely misoriented a-axis domains (REBCO a-axis || sample normal), as well as regions with well-textured c-axis orientation (REBCO c-axis || sample normal) but with significant variation in cation disorder. The results are complemented with linear scans carried out by two-dimensional x-ray diffraction, which do identify the a-axis grain regions but do not detect any apparent anomaly in the cation-disordered region detected by Raman micro-spectroscopy. The results indicate that scanning Raman spectroscopy has the potential to be utilized as a fast, insightful, and reliable characterization, quality, and process control technique for both CC optimization and increase of manufacturing yield.
Robust and accurate decoding of hand kinematics from entire spiking activity using deep learning
Authors: Ahmadi Nur , Constandinou Timothy G , Bouganis Christos-Savvas
Published: January 2021

Objective. Brain–machine interfaces (BMIs) seek to restore lost motor functions in individuals with neurological disorders by enabling them to control external devices directly with their thoughts. This work aims to improve robustness and decoding accuracy that currently become major challenges in the clinical translation of intracortical BMIs. Approach. We propose entire spiking activity (ESA)—an envelope of spiking activity that can be extracted by a simple, threshold-less, and automated technique—as the input signal. We couple ESA with deep learning-based decoding algorithm that uses quasi-recurrent neural network (QRNN) architecture. We evaluate comprehensively the performance of ESA-driven QRNN decoder for decoding hand kinematics from neural signals chronically recorded from the primary motor cortex area of three non-human primates performing different tasks. Main results. Our proposed method yields consistently higher decoding performance than any other combinations of the input signal and decoding algorithm previously reported across long-term recording sessions. It can sustain high decoding performance even when removing spikes from the raw signals, when using the different number of channels, and when using a smaller amount of training data. Significance. Overall results demonstrate exceptionally high decoding accuracy and chronic robustness, which is highly desirable given it is an unresolved challenge in BMIs.
Dynamics of impulse seals with tubular feeders
Authors: Martsynkovskyy V A , Hudkov S M , Zahorulko A V , Kundera Cz
Published: January 2021

The paper presents a technique for calculating forced axial oscillations and stability of impulse seals with tubular feeders. Unlike the existing methods of calculation, wherein, for the sake of simplicity, the influence of the feeder conductance is neglected, this article describes a conductance effect on the dynamic characteristics of the impulse face seal. The proposed calculation technique makes it possible to determine amplitudes of forced oscillations of the axially movable bushing and stability limit for the geometric parameters chosen in the static calculation. As an example, the authors described a calculation of the impulse face seal of the rotor of the main Reactor Coolant Pump (RCP 20000-100). The amplitude and phase-frequency characteristics for different values of the nominal gap are constructed.
Research of strength characteristics and optimization of parameters of case structures using holographic interferometry
Authors: Dzyuba A P , Selivanov Yu M
Published: January 2021

The article presents a method for studying the strength characteristics and optimizing the parameters of the casings of pumping and compressor equipment, gearboxes, motors, etc. structures by the reduced density of stripes on their holographic interferograms. It was used to study the properties of a cylindrical shell with an optimal reinforcing pad in the zone of action of a radial concentrated force. A rational redistribution of the material of the ribbed plate, bent by a transverse concentrated force, has been carried out. The deformation of the crankcase of the gearbox and clutch of a car in all gears is investigated, recommendations are given for the rational redistribution of its material. The results show that holographic interferometry makes it possible to assess the advantages of the optimal designs obtained, allows to significantly expand the class of hull structures, for which a high level of design solutions can be effectively implemented to ensure their rational parameters.
Nonequidistant antenna arrays synthesis based on genetic algorithm
Authors: Oznobikhin V I , Romodin V B , Shebalkova L V
Published: January 2021

A new approach to the synthesis of nonequidistant antenna arrays with uniform distribution based on the Genetic Algorithm of the global extrema search is introduced and analyzed. The technique is demonstrated for various uniform antenna array structure. The radiation pattern of the nonequidistant antenna array is formed using the Genetic Algorithm to reduce a side lobe level. A mathematical formula is presented to highlight the operation of objective function minimization.
Principles of manufacturing of DC on-board harness for a spacecraft based on 3D technology
Authors: Efremov S , Karpov N , Leonov A
Published: January 2021

This article describes in detail principles of manufacturing of DC on-board harness for spacecraft based on a new 3D design technology. This technology puts together all activities of on-board harness production, starting from electrical design and up to the final product readiness. Based on the analysis performed we proposed: necessary software, methods of wires and connector contacts connection, applicable wires and connectors available in Russian and European markets, shielding and insulating materials, test methods. The article discusses benefits of lightweight supply buses technology implementation (as compared to bundle of wires), which are: mass reduction, electrical performances stability improvement, lesser capacity between supply lines, better interference immunity, better thermal performances.
Recognition of english and russian-language texts based on frequency characteristics
Authors: Kotov Y , Sanina O
Published: January 2021

Distinction of texts in one language from texts in others is necessary to solve the problems of automated text analysis. The paper presents criteria and critical values for recognizing English-language and Russian-language texts. The obtained criteria are estimated by experiments. The paper describes the methods to estimate the size of character codes and to identify a space character in a text. The algorithm for recognizing texts in the English and Russian languages with arbitrary encoding is studied and its accuracy is estimated experimentally.
Optimal voltage regulator of power supply system for submersible processing equipment
Authors: Bukreev V G , Rulevskiy V M , Shandarova E B , Bystrov E A
Published: January 2021

The article considers the synthesis of the optimal voltage regulator for the electric power supply system of the electromechanical complex of the submersible apparatus with the power transmission through the cable line. Based on the reduced linearized model of the multidimensional nonlinear control object the regulator with adjustable parameters is synthesized, providing the DC voltage stabilization at the power supply system load. The variant of building proportional feedback on output state variables is used for the regulator in the system with parametric and external disturbances. Due to the technical impossibility of measuring the voltage on the load, a combined optimal regulator with negative feedback is organized, which makes it possible to stabilize the voltage at the payload within the specified limits when receiving data from the output filter of voltage source inverter.
Knowledge models in computer-aided manufacturing systems
Authors: Zakharova A A , Grebenyuk Y V
Published: January 2021

Despite of vast amounts of information and considerable opportunities to process it with computer-aided manufacturing systems, personal experience and lore of experts become a role-defining category in the issues of creating and making technical decisions. This should be factored into the process of creating instruments for decision making, which are based on computer-aided manufacturing systems. Efficient decision-making models, as well as models of factors (determinants) evaluation, should include expert knowledge data. In this connection, it is of burning importance to find ways to formalize expert knowledge into a code readable by computer-aided manufacturing systems. The research paper presents three determinant (criteria) evaluation models which help make technical decisions. The models include expert knowledge data formalized by means of linguistic variables. The research paper also presents recommendations on how to opt for a proper model, including requirements, and peculiarities of expert information collection matters.
Intelligent analysis of digital economy competencies in agriculture labor
Authors: Aletdinova A A , Bakaev M A , Astapchuk V A
Published: January 2021

As information becomes the main resource and production factor, there is widely declared need for digital competencies and skills in employees. This demand is uneven between industries and regions and is often biased due to companies’ and organizations’ desire to “keep up with the times”. In our paper we focus on employees’ digital economy competencies in agriculture, which is traditionally considered a rather low-tech sector, and compare them to several other industries with varying degrees of informatization. To negate the possible biases, in our analysis we rely on online data – vacancy ads published by companies at job-related portals – instead of traditional statistics. The online data was collected by our dedicated labor market monitoring intelligent system that has been in operation since 2011. The digital economy competencies were divided into 6 types: 1) intellectual and educational, 2) communicational, 3) motivational, 4) managerial, 5) ICT, and 6) ecological. We further use the groups and the wordings of the competences in online job-related ads to fill-in the “competencies specifications” thesaurus. Finally, we calculate frequencies for the digital economy competencies in vacancies for the different industries. We found that in agriculture the most demanded were the intellectual and educational, managerial and ICT-related ones.
Crowd intelligence methods for identifying corruption-prone legislative acts
Authors: Rakhvalova D , Kurcheeva G , Rakhvalova M , Bakaev M
Published: January 2021

The article is dedicated to the problems in automation of anti-corruption expertise of legislative acts, which gets increased attention within today’s Computational Law field. We carried out the analysis of the corruption-related factors frequency and outlined approaches for assessing the risks involved with their presence in a legal document. The frequency was classified per the identified attributes of regulatory legal acts: the year of adoption, the social field of the legal regulation, the level. The analysis of legal documents was carried out using the “crowd-intelligence” approach – performing relatively elementary tasks of annotating data for machine learning by people who are not expert lawyers. The results of our work can contribute to improving the effectiveness of anti-corruption expertise and support decision-making by the experts in the field.
New technology for assessing platelet aggregation activity
Authors: Tyutrin I I , Li L , Gubarev F A , Zhukov E L , Slizevich D S , Liushnevskaya I D , Kalganov I S
Published: January 2021

In this paper, we discuss an application of the method of the Digital Laser Speckle Image Correlation method (DIC) for studying the aggregation function of platelets in whole blood with the maximum standardization of the pre-analytical and analytical stages of the study. Materials and images are provided, methods are explained.
Research on the effect of test parameters on signal contrast and accuracy of determining the size of a defect
Authors: Radchenko V , Palumbo D , Ryngach N , Bobin K , Kurlaev N
Published: January 2021

Currently, is used several non-destructive testing methods for detecting defects in the composite materials. The most potential is methods non-contact scanning for a large surface area with relative insensitivity to environmental disturbances. In this regard, are developed methods for defect detection in composites, all of which have own peculiarity. A fundamental difference concerns the overall length of time is required for non-destructive testing and analysis of thermographic data from the infrared camera, first of all, for large-scale structure. This research work has been conducted a quantitative way of analyzing data to optimizing the testing parameters in terms of testing time and signal-to-noise ratio. In particular, were carried a few tests out on stringers of carbon fiber reinforced panels. These tests included lock-in thermography technique with simulated defects, which has been used for finding parameters to correct detect dimensions of defects.
Analysis of the FACTS devices impact on the transmission line protection operation
Authors: Ruban N Yu , Gusev A S , Bay Yu D , Razzhivin I A
Published: January 2021

The effect of the static synchronous compensator (STATCOM) on distance protection of a high-voltage transmission line is studied in this article. To carry out the research stated in the topic of the paper, an experimental scheme was developed, equipment was selected, the operation settings of the 3 stages of distance protection were calculated and quad characteristics were built on their basis. All listed above, as well as further experiments, were carried out by the real time digital simulator. The STATCOM model was integrated in the scheme and set next. A series of experiments was carried out: two-phase and three-phase short circuits in various nodes of the scheme with and without the compensator and in various connection nodes. After all the experiments were carried out, appropriate conclusions were made about the impact of FACTS devices on the operation of distance protection. Possible ways to solve detected problems were also proposed.
Visual shape and position sensing algorithm for a continuum robot
Authors: Manakov R A , Kolpashchikov D Y , Danilov V V , Laptev N V , Skirnevskiy I P , Gerget O M
Published: January 2021

Continuum robots represent an actively developing and fast-growing technology in robotics. To successfully implement control and path planning of continuum robots it is important to develop an accurate three-dimensional shape and position sensing algorithm. In this paper, we propose an algorithm for the three-dimensional reconstruction of the continuum robot shape. The algorithm is performed during several steps. Initially, images from two cameras are processed by applying pre-processing and segmentation techniques. Then, the gradient descent method is applied to compare two-dimensional skeleton points of both masks. Having compared these points, it finds a skeleton of the robot in a three-dimensional form. Additionally, the proposed algorithm is able to define key points using the distance from the robot base along the center line. The latter allows controlling the position of points of interest defined by a user. As a result, the developed algorithm achieved a relatively high level of accuracy and speed.
Technology of partial discharge detection by means analysis of impulse interaction
Authors: Mytnikov A , Strugov V
Published: January 2021

In this paper the approach based on impulse analysis for partial discharge (PD) control and identification for high voltage insulation are summarized and the experimental research of impulses of different nature for detection some typical PD defects are discussed. Some physical effects at different voltage levels are shown and a method for the representation and characterization of the PD is introduced. Special test cells with different types of defects such as a streamer corona and pore inside oil-paper insulation of condenser type are used for the investigations. The experimental procedure for PD identification by means of impulse form transformation is shown and discussed. Experimental equipment and measurements are described. It is shown that using of impulse of nanosecond duration and commutative impulse allows the characterization and controlling PD in high voltage insulation.
Model of on-line control for the smart object by communication technologies
Authors: Maksimova Y A , Barchukov D , Slobodyan S
Published: January 2021

Based on analysis of opportunities of usage existing models, methods and techniques for on-line monitoring and control of unmanned dynamic objects, a mathematical model of remote estimation of distance to wire-controlled unmanned mobile object is proposed. The presence of model and techniques of remote estimation of distance to wire-controlled unmanned object increases the reliability of control for exclusion of critical situations in the strict radio counteraction conditions and powerful electromagnetic jamming setting during control.
Varying spatial orientation of photoelectric panels as method of managing graph of electric energy generation
Authors: Daus Y , Yudaev I , Desyatnichenko D
Published: January 2021

One of the main issues in the determining layout of photovoltaic installations is choosing optimal parameters for photovoltaic panels and auxiliary equipment and duplicating energy sources, which makes it possible to justify economically the electrical energy generation. Regularity of solar radiation variation for the studied geographical point throughout the year, and the influence of atmospheric phenomena, as well as the dynamics of daily and seasonal electrical energy consumption must be considered, which will help to predict the operation mode of the plant, and match generation and consumption schedules. Variation of tilt angle of the photovoltaic module receiving surface relatively to horizon and cardinal points makes it possible to manage the schedule of power generation at solar plant and to match it with the load curve, due to the maximum possible convergence of them, as change in the spatial orientation of the photovoltaic panel surface makes it possible to shift the maximum of solar radiation flux in time. The results of the experimental research also revealed the dependence of the current produced by the photoelectric panel on its spatial orientation due to the change of the incoming solar radiation flux on it.
Glass composite modified with silicon carbide and gallium arsenide, that absorbs electromagnetic radiation
Authors: Kazmina O V , Semenova V I , Dorozkin K V
Published: January 2021

The possibility of using waste of semiconductor manufacturing containing silicon carbide and gallium arsenide as an effective additive in radio absorbing material preparation was established as a result of research. The resulting material meets the requirements of effective porous electromagnetic radiation absorbers of extremely high frequency range: maximum absorption and minimum reflection of electromagnetic radiation, fire safety, the minimum allowable level of toxic and hazardous substances.
Studies of integrated natural capillary-porous coatings
Authors: Genbach A A , Bondartsev D Y , Beloev H I
Published: January 2021

There were developed devices with porous coatings that can eliminate the appearance of cracks in the chambers and nozzles due to the powerful thermodynamic screen of three heat sources, and to arrange cutting of reinforced concrete structures with detonation high-temperature flares flowing from combustion chambers and nozzles cooled by capillary-porous coatings. In studies, the holography method was used. The expected economic effect from the one burner is approximately 200-300 $. The environment needs to be reduced by the cooling system’s energy consumption. The studied chambers and burners can be implemented in the thermal power plants, especially in the gas turbine equipment. Capillary-porous and flow-through cooling systems demonstrated high reliability, however, the first system can reduce the cooler consumption by tens of times (up to 80 times). The design and manufacturing of hybrid porous surfaces make them integrated and multifunctional, provides the possibility to work with higher critical loads, and enables a mobile process for monitoring the limiting condition of coatings.
A study of thermal devices with porous coatings
Authors: Genbach A A , Bondartsev D Y , Beloev H I
Published: January 2021

Thermal devices (mechanisms) with porous coatings designed for combustion chambers of gas turbine units, as well as for cutting and drilling turbo foundations of power plants, which solve the problem affiliated with the appearance of cracks from the reflected wave, have been developed and studied. The porous coating provides a powerful thermodynamic screen in the similitude of three heat sources. The studies were unleashed on five samples with different porosity and hardness values (5 ÷ 30%). Thermal movements, deformations, and stresses were recorded on a holographic unit in real-time. A thermal device in the form of a rocket-type burner with a detonation jet has proved high efficiency for a capillary-porous and flow-through cooling system. Photographs of combustion chambers and nozzles studied depending on their geometry and thickening of the nozzle wall, an excess oxidizer (0.3 ÷ 0.8), and operating conditions until of the metal limiting condition (1106 W/m2) are presented. The optimal geometry of the chambers and nozzles either the type of porous structure was specified. It has been found that the economic effect is 200-300 $ for 1 burner, and the consumption of coolant is reduced several times.
Effect of tool travel speed on tensile strength of friction stir welded dissimilar joint of aluminium AA6061 T6 alloy and maraging M250 steel
Authors: Karthikeyan M , Jonah
Published: January 2021

Friction stir welding (FSW) is a promising welding method to produce dissimilar joints between steel and aluminium. The formation of the intermetallic compound layer at the dissimilar joint interface affects the joint mechanical properties, which are also influenced by the FSW process parameters. In the present research work, M250 Maraging steel and AA6061 T6 aluminium alloy were joined by FSW. The joints were prepared with five different tool travel speeds ranging from 0.33 mm s−1 to 1 mm s−1 using a tapered tool pin made by tungsten carbide material, keeping tool rotational speed constant. The welded joints were analyzed for their tensile behaviour and microstructural change, including hardness measurement. The failed samples are analyzed using a scanning electron microscopy device for their mode of failure. In the Energy Dispersive X-Ray Spectroscopy (EDS) analysis, the formation of intermetallic compound (IMC) layers of Fe3Al, Fe4Al13, and Fe2Al5 are observed. When the thickness of the IMC layer increases, the joint strength decreases. It is found that the welding speed influences the thickness of the IMC layer formed, causing variation in the strength of the dissimilar joint. Better joint efficiency is obtained at a tool travel speed of 0.67 mm s−1.
Advances in reconfigurable optical design, metrology, characterization, and data analysis
Authors: Kim Dae Wook , Smith Greg A , Dubin Matt , Lowman Andrew , Oh Chang-jin , Quach Henry , Kang Hyukmo , Yoo Hyemin , Trumper Isaac , Graves Logan , Aftab Maham , Davila-Peralta Christian , Hyatt Justin , Choi Heejoo
Published: January 2021

Reconfigurable freeform optical systems greatly enhance imaging performance within non-symmetric, compact, and ergonomic form factors. In this paper, several advances improve design, testing, and monitoring of these systems. Specific enhancements include definition of polynomials for fast and efficient parameterizations of vector distributions in non-circular apertures and merit based function optimization. Deflectometry system improvements enable metrology for almost any conceivable optic shape and guide deterministic optical figuring process during the coarse grinding phase by including modulated infrared sources. As a demonstration of these improvements, parametric optimization is tested with the tomographic ionized-carbon mapping experiment, a reconfigurable optical system. Other case studies and demonstrations include metrology of a fast, f/1.26 convex optic, an Alvarez lens, and real-time monitoring of an array of independently-steerable hexagonal mirror segments as well as an induction formed surface and inflatable Mylar mirror.
Impact monitoring of CFRP composites with acoustic emission and laser Doppler vibrometry
Authors: Grigg S , Almudaihesh F , Roberts M , Pullin R
Published: January 2021

The use of Acoustic Emission (AE) to detect impacts is of interest within industries where vital components are prone to impact damage, in particular where Carbon Fibre Reinforced Polymers (CFRP) are used, as damage can often go un-noticed within them. For AE monitoring of impacts piezoelectric sensors are used to detect the ultrasonic wave produced by an impact. Classification is also possible of these waves enabling a distinction between damaging and non-damaging impacts. These sensors do however have resonance, so do not give an accurate picture of how the waves propagate, better knowledge would enable better selection of sensors. Laser Doppler Vibrometry is a non-contact and non-resonant method of analysing the surface displacement on a structure. In this study, a vibrometer was used to monitor CFRP plates during impact to assess its applicability for distinguishing between damaging and non-damaging impacts, compared with a surface mounted AE sensor. The vibrometer was able to detect both low frequency flexural modes due to the impact process and the higher frequency extensional modes, initiated by damage. When compared to the AE sensor the vibrometer was comparable in its results, and unlike the sensor, not susceptible to resonance or decoupling. For the tested material the vibrometer identified frequencies greater than 20 kHz to be associated with damaging impacts.
Association of Longitudinal Changes in NT-proBNP With Changes in Left Atrial Volume and Function: MESA
Authors: Varadarajan Vinithra , Ambale-Venkatesh Bharath , Hong Seo Young , Habibi Mohammadali , Ashikaga Hiroshi , Wu Colin O , Chen Lin Y , Heckbert Susan R , Bluemke David A , Lima Joao A C
Published: January 2021

BACKGROUND

The mechanism of left atrial (LA) remodeling is poorly understood. The aim of this longitudinal study was to investigate whether changes in NT-proBNP levels relate to alterations of LA structure and function over time in a multiethnic population.

METHODS

From the prospective cohort study, the Multi-Ethnic Study of Atherosclerosis, our analysis included 1,838 participants who underwent cardiac magnetic resonance imaging at the baseline and 10-year examinations, had NT-proBNP levels available at both time points, and did not develop heart failure, myocardial infarction, and/or atrial fibrillation. Multivariable linear regression was used to analyze the association between NT-proBNP level (log-transformed) at the 2 time points and change in LA volumes, LA emptying fractions (total, active, and passive), and LA longitudinal strain. Log NT-proBNP was categorized into Low-Low (N = 681), Low-High (N = 238), High-Low (N = 237), and High-High (N = 682) based on the median value at both time points.

RESULTS

With the Low-Low group as the reference group, the High-High group experienced a greater increase in LA maximum and minimum indexed volumes: 3.1 ml/m2 (95% confidence interval 1.98, 4.20) and 2.7 ml/m2 (1.89, 3.51), respectively. The High-High group also experienced a greater decrease in LA total, passive, active emptying fraction, and longitudinal strain: −3.3% (−4.46, −2.11), −0.9% (−1.80, −0.02), −4.2% (−5.55, −2.76), and −2.3% (−3.80, −0.72), respectively. The Low-High group had similar associations, but the effect sizes were not as high.

CONCLUSIONS

Adverse LA remodeling over 10 years of follow-up strongly correlates with prolonged elevated levels of intracardiac stress, as assessed by NT-proBNP levels.