bluuebunny/crossref_metadata_2025_split huggingface dataset:
Traceable x-ray focal spot reconstruction by circular edge analysis: from sub-microfocus to mesofocus
Authors: Bircher Benjamin A , Meli Felix , Küng Alain , Sofiienko Andrii 
Published: March 2022

Abstract
The size and shape of the focal spot, i.e. the area where x-rays are generated in an x-ray tube, is a key figure of merit of a radiographic imaging system, because it governs the achievable resolution and, if the shape is irregular, can introduce anisotropic blur in the radiographs. Size and shape are mainly determined by the diameter of the accelerated electron-beam and electron interactions with the target material. Since focal spot parameters change over time, due to target wear and drift in the electron optics, traceable methods to monitor the focal spot size and shape are required. Here, we present a method to map the 2D intensity distributions of focal spots, ranging from sub-microfocus (0.1 µm) to mesofocus (>50 μm). The method evaluates radial profiles of a circular aperture and applies filtered back projection to reconstruct the focal spot intensity distribution. Special emphasis is placed on traceability and influence factors, such as image noise and aperture geometry. The method was validated over a focal spot range from 0.3 µm to 200 µm. Experimental results were compared to complementary methods, using line pair gauges (JIMA) for microfocus (1 µm–10 µm), e-beam characterisation for sub-microfocus (0.3 µm–1.0 µm), and pinhole camera imaging for mesofocus spots (50 µm–200 µm). Good agreement between the focal spot reconstruction and the complementary methods was achieved. Limitations due to edge penetration, caused by the finite thickness of the circular aperture gauge, were experimentally verified. From these findings, we derived recommendations for an improved gauge geometry, regarding its thickness and the aperture diameters. The method perfectly complements the well-established pinhole imaging, which is limited to focal spots larger than ∼50 µm.
Three distinct phases of electron heating in an rf-driven atmospheric-pressure plasma jet
Authors: Park Sanghoo , Yoon Sung-Young 
Published: March 2022

Abstract
Cold plasma jets represent one of the most attractive and versatile plasmas, and active studies on plasma properties such as electron density (n
e) and temperature (T
e) have facilitated the development and implementation of plasma jets. Here we demonstrate the temporal evolution of n
e and T
e in a radio-frequency (rf)-driven argon plasma jet operating at atmospheric pressure. The plasma jet is driven by 5 MHz sinusoidal rf power modulated by a 50 kHz square pulse with a 75% duty ratio. A 532 nm Nd:YAG laser is applied to the plasma, and laser Thomson scattering measurements are performed using a triple-grating spectrometer coupled to an intensified CCD camera. From this investigation, we find that n
e and T
e vary during the pulse repetition period of 20 μs in the ranges of (2–12) × 1018 m−3 and 0.3–6.0 eV, respectively. With respect to the 5 MHz period (200 ns), T
e varies with the rf oscillating field while n
e remains constant. Special attention is given to three distinct electron characteristics depending on the pulse phase in the plasma jet—ionizing (on-pulse), stationary and recombining (off-pulse) states. Our measurements will be valuable for related experimental and numerical plasma research and provide further insights into the effect of rf pulsing on the electron kinetics in atmospheric-pressure plasmas.
Epitaxial growth of GaAsBi on thin step-graded InGaAs buffer layers
Authors: Paulauskas T , Devenson J , Stanionytė S , Skapas M , Karpus V , Čechavičius B , Tumėnas S , Strazdienė V , Šebeka B , Pačebutas V 
Published: March 2022

Abstract
Molecular beam epitaxy growth and analysis of GaAsBi on compositional step-graded InGaAs buffer layers are presented in this study. The developed buffer is only 240 nm thick, exhibits very low surface roughness while reaching up to 0.46% lattice-mismatch with a GaAs substrate. Reciprocal-space mappings showed that 500 nm thick GaAsBi layers with 2.7%–5.3% Bi remain pseudomorphic with the InGaAs buffer, in contrast to GaAsBi grown on GaAs that were found to incur up to 50% lattice relaxation. CuPtB-type ordering and associated polarized photoluminescence were also found in the bismide layers grown on the InGaAs buffers. Optical anisotropy of a strain-free 2.7% Bi GaAsBi was further analysed by a suite of optical techniques indicating that the valence band splitting is ∼40 meV. This study advances synthesis techniques of thick GaAsBi layers for optoelectronic device applications.
Critical current and loss character of quasi-isotropic strands with resistance
Authors: Li Shuo 
Published: March 2022

Abstract
A quasi-isotropic strand has a central rotational symmetry structure which shows good isotropic performance on magnetization loss when the strand is subjected to an externally applied alternating magnetic field in various directions. This paper studies the critical current and ac loss character of quasi-isotropic strands by considering the resistance between tapes based on the minimum electromagnetic entropy production method. The quasi-isotropic strands show resistance dependence on critical current, transport loss, and magnetization loss. The resistance between tapes can increase the critical current without significant increases in the total loss. High-frequency excitation conditions do not increase the loss per cycle either. The results indicate that quasi-isotropic strands are highly suitable for power cables and other high-power applications.
Stability of KdV solitons with respect to transverse perturbations: Absolute and convective instabilities
Authors: Ruderman M S , Petrukhin N S , Pelinovsky E 
Published: March 2022

Abstract
We study the stability of one-dimensional solitons propagating in an anisotropic medium. We derived the Kadomtsev-Petviashvili equation for nonlinear waves propagating in an anisotropic medium. By a proper variable substitution this equation reduces either to the KPI or to the KPII equation. In the former case solitons are unstable with respect to the normal modes of transverse perturbations, and in the latter they are stable. We only consider the case when the solitons are unstable. We formulated the linear stability problem. Using the Laplace–Fourier transform, we found the solution describing the evolution of an initial perturbation. Then, using Briggs’ method we studied the absolute and convective instabilities. We found that a soliton is convectively unstable unless it propagates at an angle smaller then critical with respect to a critical direction defined by the condition that the group velocity is parallel to the phase velocity. The critical angle is proportional to the ratio of the dispersion length to the soliton width, which is a small parameter. The coefficient of proportionality is expressed in terms of the phase speed and its second derivative with respect to the angle between the propagation direction and the critical direction. As an example we consider the stability of solitons propagating in Hall plasmas.
Dynamical dark energy models in the light of gravitational-wave transient catalogues
Authors: Escamilla-Rivera Celia , Nájera Antonio 
Published: March 2022

Abstract
The study of current gravitational waves (GW) catalogues provide an interesting model independent way to understand further the nature of dark energy. In this work, we present an update of the constrains related to dynamical dark energy parametrisations using recent Gravitational-Wave Transient catalogues (GWTC-1 and GWTC-2) along with Type Ia supernova (SNeIa) and Cosmic Chronometers (CC) catalogues. According to our Bayesian results using the full SNeIa+CC+GW database, the ΛCDM model shows a strong preference against two dark energy parameterisation known as Barboza-Alcaniz (BA) and the Low Correlation (LC) models. Also, we obtain a very strong preference against the Chevallier-Polarski-Linder (CPL) model. Furthermore, we generated a mock GW catalogue and estimate that we require approximately 1000 standard sirens to have a constrain of H
0 within 1% relative error, quantity that is out of reach of current standard sirens candidates in GWTC-1 and GWTC-2 catalogues.
The protection of megascience projects from deepfake technologies threats: information law aspects
Authors: Galyashina E I , Nikishin V D 
Published: March 2022

Abstract
The paper examines the potential threats of the malicious use of deepfake technology to destabilize and discredit megascience projects in the global information space. The phenomenology of using artificial intelligence (AI) to create video recordings and voice messages, in which people do and say something that did not take place in reality, is considered. Special attention is paid to speech synthesis technologies based on arbitrary text and spoofing, i.e. replacing the speaker’s personality while preserving the content of the original speech message. The authors’ definition of a voice deepfake is as follows: an artificial creation of digital voice clones of a person for the purpose of intellectual or material forgery (fabrication of a pseudo-real information and communication event). A specific classification of deepfake technologies according to the types of their criminogenic use is given in the article. The authors highlight the imperfection of the Russian legislation on the legal protection of the individual voice of a person as an intangible value and on the protection of individuals from the unauthorized use of voice personal data taking into account the policy of social networks (Facebook, Twitter, TikTok) aimed at protecting users from synthesized audio and video disinformation. Based on the results of the research, a number of decisions are proposed to change the criminal and civil legislation in order to ensure the national security of the state, to protect international megascience projects, other scientific activities and individuals from the negative consequences of the potentially destructive and / or criminal use of voice deepfakes, including discrediting and defaming international megascience projects and their representatives in the media environment. The proposed legislative amendments may be used in other contexts by foreign countries and interstate associations.
Ensuring information security in the field of remote work
Authors: Kolomoets E 
Published: March 2022

Abstract
Remote work is a forced measure introduced by employers in order to prevent a viral infection. For employees, there are pluses in remote work - saving time and money on the road and high labour productivity because nothing distracts. There is a separate issue of information security for the employer when organising such a work regime for their employees. Any use of materials is allowed only with a hyperlink. Nowadays, in the realities of distance work, information security is coming first. Employees send all the information online; they use their data and send confidential information. Protection of personal data becomes a crucial point. The article deals with problems of ensuring information security in the field of remote work. The problems of information security during restrictive actions in connection with the coronavirus pandemic and the transfer of personnel to remote work are discussed. The threat of information leaks through remote workers is relatively high since the specialists responsible for the organisation’s information security do not have the opportunity to apply the entire arsenal of technical means and policies, with the help of which security is ensured at workstations in the office. Information leakage will lead to severe problems, so it is essential to consider what means you can use to ensure the company’s information security.
New challenges and approaches in training personnel for research projects of the “MegaScience” class
Authors: Barbashina N S , Astapov I I , Delov M I , Moshkova D M , Vasiliev A N 
Published: March 2022

Abstract
MegaScience projects are unique scientific experiments and facilities of a large scale that were initiated to allow to go beyond modern knowledge in the field of fundamental sciences and open up new opportunities in the technological development. The implementation of such complex projects requires the combined efforts of many scientists and institutions at national and multinational level. The paper presents an analysis of new trends in the training of researchers in the field of elementary particle physics, high energy physics and cosmophysics for research projects and experiments at MegaScience facilities. The authors consider the vast experience of extensive training of MEPhI students for fundamental science and analyzed new approaches to organizing the individual training of researchers at the university. The result of this work was presented and discussed within the proceedings of the Third Conference “Personnel training and legal support for the implementation of scientific projects of the Mega-science class” organized by National Research Nuclear University MEPhI and Kutafin Moscow State Law University on 17 June 2021.
Training of academic lawyers for implementation of high-tech research projects (“Digital Law”, “Megascience” and “Lex genetica” projects case study)
Authors: Zakharova M V 
Published: March 2022

Abstract
The legal profession has both conservative and innovative features. On the one hand, present-day lawyers are the heirs of the centuries-old tradition of global jurisprudence. On the other hand, the technological challenges of the external environment inevitably transform not only the legal map of the world, but also the peculiarities of training for modern legal professionals. The article deals with the main transformational paradigms of legal professionals training, using the example of three high-tech spheres of public life – genetics, digital economy and mega-science installations development. Academic lawyers (legal scholars) are in many ways at the forefront of the present-day jurisprudence, defining both the present and the future of the global legal space. Their training takes longer than the standard education course for lawyers. The data of the Russian legal system and the legal systems of other countries, as well as international legal practice, served as the empirical basis for the research.
Mechanisms for attracting foreign scientists
Authors: Karandaev I Y , Lozovskij D L 
Published: March 2022

Abstract
The brain drain problem is typical not only for the Russian Federation, but also for other developing and developed countries. The article presents the mechanisms of attracting foreign scientists on the example of the European Union, the People’s Republic of China, and the Federal Republic of Germany. On the basis of the analysis and generalization, the features of the mechanisms used to attract foreign scientists and their effectiveness are highlighted.
Frequency Increments Optimization Based on IPSO to Extend Beam Dwell Time for Frequency Diverse Array
Authors: Pan Yuwen , Yang Yuanwang , Jiao Libin 
Published: March 2022

Abstract
Compared with traditional phased array radar, frequency diverse array (FDA) can form a range-dependent beampattern and overcome the shortcoming that the traditional phased array radar cannot effectively control the range direction of the transmit beam. Nonuniform linear frequency increments has been widely applied in FDA to promote the performance of FDA. However, few methods can effectively extend the beam dwell time. In this paper, we propose an improved particle swarm optimization algorithm (IPSO) that can adjust the frequency increment of every array element to extend the dwell time of the beam within a period of time. Numerical simulation results show that our method can outperform other existing methods, which implies that a more stable and flexible FDA communication system can be achieved for the proposed method.
Anti-asphyxiation System for Children in Vehicle Based on Multi-sensor Fusion
Authors: Peng Shaolong , Yang Bokang , Yang Zhihui , Shi Shaoyue 
Published: March 2022

Abstract
With the rapid development of automobile industry, cars have been widely used in thousands of households. But the car brings convenience to people’s life, at the same time, the safety hidden trouble it brings is also more prominent and serious. In recent years, more and more accidents caused by asphyxiation of children in cars have prompted the scientific community to pay attention to and study this phenomenon. Therefore, we design a vehicle anti-asphyxiation system based on multi-sensor fusion.
Bayesian Regression Analysis of Spatio-temporal Location Information of Ship Electromagnetic Signal
Authors: Wang Min , Sun Chong , Wu Rangcheng , Shi Xiangqian 
Published: March 2022

Abstract
For spatio-temporal location information of electromagnetic signals according to maritime ship targets, the regression model based on Bayesian statistics is established based on the Bayesian estimation method, and some examples are analyzed. The results show that the model reduces the error, improves the accuracy of the sample data, significantly improves the data pretreatment effect, and effectively facilitates the further modeling and analysis of the target identification problem, so as to increase the credibility of the ship target identification.
Allocation Structure Optimization of Distributed Power Supply Based on Improved Self-adapting Cuckoo Algorithm
Authors: Li Lei , Gao Guige 
Published: March 2022

Abstract
Aiming at the problems of environmental protection and economy caused by the integration of distributed power (DG) into distribution network, an optimal allocation model of distributed power was established with generation cost, network loss cost and DG environmental cost as the optimization objectives. In order to solve the model, an improved adaptive cuckoo algorithm was introduced, which combined the discovery probability and scaling factor of the adaptive strategy. Through the example analysis of IEEE-33 bus, the simulation results of different algorithms are compared, for which, in distributed power allocation structure, the availability and advantages of this improved algorithm optimization are verified.
Digital Analysis of Movements on Characters Based on OpenPose and Dlib from Video
Authors: Ye Kai , Dong Jianmin , Zhang Lijun 
Published: March 2022

Abstract
In order to avoid the disadvantages of complex operation and expensive equipment for the extraction method of motion capture systems and other equipment , a method which can extract key points of characters movements was proposed based on video of Tibetan drama with OpenPose and Dlib. And, the movement trajectory and movement fluctuation amplitude which were obtained by digital analysis from characters’ movement were used as indicators to provide a quantitative plan for movement essentials of Tibetan drama’s performing arts. The digital analysis was implemented by tracking key points’ two-dimensional coordinate data with the form of line chart and reflecting movement fluctuation amplitude with absolute difference of the same key point’s two-dimensional coordinate data belonged to two frame of video. Experiments showed that this method was suitable for video and was correct and effective in the image coordinate system, which provided a reliable foundation for the digital analysis.
A Text Location Method for Sign Based on Pixel-level Gradient Ray Images and Edge Contour Mapping
Authors: Du Jiani , Bai Jun , Zhou Guanglu 
Published: March 2022

Abstract
Compared with deep learning methods, traditional image processing methods have lower computational costs and have advantages for typical problems such as sign text, this paper proposes a sign text location method based on pixel-level gradient ray map and edge contour mapping. First, based on image pre-processing, the pixel-level gradient ray map is obtained by using the Stroke Width Transform. Then, using the Maximally Stable Extremal Region method to locate the irregular text candidate area in the ray map. At the same time, add a mask layer to filter the irregular candidate area, and then regularize the candidate area and perform Non-Maximum Suppression processing. Finally, the background non-text candidate area is processed by extracting the mapping of the closed edge contour of the image, and the remaining text area positioning candidate frame coordinates are mapped back to the original picture. The experimental results show that the method is simple and clear, the effect is remarkable, and it has good robustness to the sign of different sizes.
A S-transform Based Algorithm for Doppler Frequency Rate-of-Change Estimation from Coherent Pulse Train
Authors: Lan Zhangfu , Peng Huafeng , Zhao Peiyan 
Published: March 2022

Abstract
The traditional Fourier correlation method has the problem of poor accumulation effect, which leads to the low estimation accuracy of Doppler frequency change rate coherent pulse signal under the condition of low signal-to-noise ratio or short pulse duration. To solve this problem, an estimation algorithm based on S-transform is proposed to estimate the Doppler frequency change rate. By means of higher time-frequency aggregation of S transform, the coherent accumulation of the coherent pulse signal is better realized; Then the high accuracy Doppler frequency change rate is obtained by using the minimum variance criterion in the phase domain. Theoretical derivation and simulation results show that the algorithm in this paper can improve the accuracy of about 1 times compared with the traditional algorithm. It lays a solid foundation for the estimation of the high-precision Doppler frequency change rate in the practical application of subsequent projects, and improves the accuracy of target positioning and tracking.
Research and Design of Remote Online Supervision System of Coal Mine Electromechanical Equipment
Authors: Chen Yunqi , Xu Jin 
Published: March 2022

Abstract
Increasing the supervision of coal mine electromechanical equipment is an urgent need to ensure the safe production of coal mines. This paper designs and develops a coal mine electromechanical equipment supervision system, which includes four parts: mine-side monitoring subsystem, mine-side data acquisition and transmission module, local-side data analysis and storage module, and coal mine electromechanical equipment supervision platform. It realizes coal mine ventilator, drainage pump, air compressors, hoists and other major electromechanical equipment online monitoring and equipment failure analysis. The system satisfies the remote online inspection and management of equipment by multi-level departments, reduces the possibility of enterprise accidents, innovates the supervision mode, and improves the efficiency of supervision.
An Anti-noise Fault Detection Algorithm for Distribution Network
Authors: He Ming , Li Yi , Zou Wan , Duan Xiangxi , Gao Jie , He Rui 
Published: March 2022

Abstract
Power fault directly threatens the safety of the power system. Aiming at the recognition ability of power line fault detection disturbed by noise, A fault detection method based on attentional mechanism combined with autoencoder neural network is proposed. The fault signal is decomposed by wavelet and the subband energy is used as the input of the neural network, which is composed of autoencoder and fault recognition network. The input signal is compressed by an encoder, represented by a small number of features, and transmitted to the fault detection network. By extracting features and training fault signals, the network structure can effectively identify fault categories. Simulation experiments based on IEEE34 show that the fault recognition rate of this method is over 98%, and it can detect distribution network faults effectively under the condition of noise, and has high anti-interference performance. It provides a new idea for fault detection of distribution networks and lays a foundation for a high robustness detection method.