bluuebunny/crossref_metadata_2025_split huggingface dataset:
Disbond contour estimation in aluminum/CFRP adhesive joint based on the phase velocity variation of Lamb waves
Authors: Tong Tong , Hua Jiadong , Gao Fei , Zhang Han , Lin Jing 
Published: June 2022

Abstract
Adhesive lap joints between composite and metal plates have been widely used in industrial fields including the automotive industry, marine manufacturing and aerospace engineering. Low quality of operation, harsh environment, adhesive aging and other disadvantages may lead to disbonding. To assess the disbond contour at an adhesive interface, this study proposes a detection method based on the phase velocity variation of Lamb waves. First, the dispersion curves of Lamb waves in both single-layer and bonded multi-layer areas are acquired using the semi-analytical finite element (FE) method. Subsequently, numerical models of Lamb wave propagation in intact and disbonded joints are established. Due to the difference in phase velocity between relevant modes, the phase difference of Lamb wave between disbonded and intact joints is quantitatively linear with the disbond length under specific excitation, which is verified by the simulated signals based on FEs. Then, a probabilistic reconstruction algorithm based on phase delay is employed to localize the disbond center. On this basis, the edge points of the disbond are acquired, and the convex envelope of these points is sketched for disbond contour estimation. As a result, both the location and shape of the disbond can be obtained, thereby providing information for subsequent assessment. The experiment is carried out on an adhesive lap joint specimen composed of an aluminum plate and a quasi-isotropic carbon fiber reinforced plastic laminate, and the results demonstrate the effectiveness of the proposed method.
Neutron yield as a measure of achievement nuclear fusion using a mixture of deuterium and tritium isotopes
Authors: Youssef Ahmed , Anwar Rania , Bashter Ibrahim I , Amin Esmat A , Reda Sonia M. 
Published: June 2022

Abstract
A mixture of deuterium (D) and tritium (T) is the most likely fuel for fusion reactors and hence the D(d, n)3He and T(d, n)4He fusion reactions are the ones that will fire fusion reactors in the future. Both of the fusion reactions produce neutrons which escape form the reactor core and can be measured directly outside the core. As the neutrons have large mean free path and neutral charge, they readily carry information about the burning fusion plasma from inside to outside the reactor core without being affected by electric ormagnetic fields. From the produced neutrons of the D(d, n)3He and T(d, n)4He fusion reactions, the neutron yield of each reaction and the neutron yield ratio of the two reactions are calculated. This ratio is of critical importance for controlling the fusion fuel burning which is a high priority issue for fusion reactor performance. Because it is very difficult to measure this ratio experimentally, accurate theoretical calculations of the neutron yield ratio besides the related deuterium and tritium energy spectra in the fusion plasma are needed. In the present work, neutron yields of the D(d, n)3He and T(d, n)4He fusion reactions have been calculated using the MCUNED, the ENEA-JSI, the DDT codes and the Geant4 toolkit. The related deuterium and tritium energy spectra have been calculated by the MCUNED code. The relation between the ion temperature and the neutron yield in the imploded fusion plasma is discussed. Calculations are compared to the available experimental data. Comparing to the other codes, the spectrum of the fusion neutrons simulated by the MCUNED is the only one that fit the experimental data.
Laboratory and On-sky Testing of an InGaAs Detector for Infrared Imaging
Authors: Batty Kristoffor , Steele Iain , Copperwheat Chris 
Published: June 2022

Abstract
We describe the results of testing a shortwave infrared CMOS camera using an indium gallium arsenide (InGaAs) detector. The new generation of InGaAs detectors offers a cost-effective alternative to mercury cadmium telluride (HgCdTe) for astronomy research, with current, off-the-shelf cameras requiring no modification before use. Testing was conducted in the laboratory and on-sky while mounted to the robotic, 2 m Liverpool Telescope using a H-band filter. The camera exhibits a dark current of 821 e− s−1 pix−1 and a bias level of 864 e− pix−1. The dark current associated shot noise is of similar size to the read noise of 32 e− pix−1 in one-second exposures. Linearity within the count region where readout noise and bit-depth saturation effects are not dominant is within a few tenths of a per cent. After field-compression by fore optics, the plate-scale yields 0.″3 pix−1, near perfect for Nyquist sampling at the La Palma site. The sky background for the H-band filter dominates the other noise sources for the instrument for one-second exposures producing sky-limited photometry. On-sky observations show that milli-magnitude precision is achieved for sources <10.7 mag and a signal-to-noise ratio of 10 is achievable for 16th magnitude with a 3 minutes total exposure time, making it an ideal follow-up instrument for sources detected in current and upcoming IR surveys.
A Speed Adaptive Path Planning Method based on Line Structured Light Information for Robotic Multi-layer/Multi-pass Welding
Authors: Liu Shijie , Lu Hong , Liu Shu , Zhang Yongquan , Wang Shaojun 
Published: June 2022

Abstract
Regarding the geometrical errors existed in the welding grooves for the large steel structures, the traditional path planning method for robotic multi-layer/multi-pass welding cannot guarantee welding quality. In this paper, a speed adaptive path planning method based on line structured light information for robotic multi-layer/multi-pass welding is proposed. Firstly, the initial welding path is planned according to the average section dimensions of grooves, which are obtained by measured data using line structured light based on the proposed section extraction algorithm. Then, considering the geometrical errors represented by the different section dimensions, the welding speed is adaptively planned to make the molten pool fit the actual dimensions of the welding pass. Simultaneously, the welding path is compensated by the relationship between the welding speed and its corresponding dimensions of molten pool. Finally, the speed adaptive multi-layer/multi-pass welding with box-style steel structures have been experimentally investigated. The proposed planning method can be implemented to improve the welding quality of the grooves in the large steel structures.
Influence Degree Analysis of Landing Points of Small-sized Fixed-wing Gliding UAV in Short Range
Authors: Jiang Tieying , Ma Xiangsen , Yang Chengwei , Mao Yukun 
Published: June 2022

Abstract
Enhancing the landing accuracy and reducing landing point dispersion of Unmanned Aerial Vehicles (UAVs) with fixed wings is critical for expanding the applications of UAVs in complex terrains. Faced with the requirement for arresting recovery for UAV landings in short range, a UAV with fixed wings is chosen as the research basis. The landing strategy for UAVs has been modified by the addition of wing flaps, dynamic compensation control, and ultrasonic sensors, among other things. Additionally, the simulation model validated the feasibility of the modified landing-recovery strategy. The Monte Carlo method is used to analyze the influence of interference sources, such as constant wind, gust, positioning error, airspeed measurement, mass, air density, processing and assembly, and control error, on landing point dispersion. Simulation results indicate that the modified landing strategy can significantly improve the short landing performance for small-sized UAVs with fixed wings.
Design and Demonstration of Eigenstructure Configuration Control Law based on Free Flight Model
Authors: Wang Yalong , Zhang Jiaqi , Qi Shenjun 
Published: June 2022

Abstract
According to the needs of advanced flight control law demonstration, a flight control law demonstration platform based on free flight model is constructed, a flight test system for flight control law demonstration is designed, the dynamic model calibration is completed and the control law based on eigenstructure configuration is designed, finally, the flight test is carried out. The test results show that the scaled free flight model can effectively complete the aerodynamic model calibration and control law demonstration. what’s more, it has strong engineering application value; Compared with the PID control law, the flight control law based on eigenstructure configuration has good control effect and strong robustness, which greatly reduces the flight test parameter adjustment and improves the flight test efficiency.
Research on Overlapping Communities in Scientific Cooperation Network
Authors: Wu Fan , Yang Can , Zheng Xue , Li Dongsheng , Chen Kebin 
Published: June 2022

Abstract
Science of science provides quantitative means for scientific research activities and can reveal the basic laws of scientific research. Taking the scientist cooperation network of Condensed matter physics, General relativity quantum cosmology and High energy physics phenomenology as the research object, the overlapping community structure in the network is detected by using the label propagation algorithm based on seed diffusion. Through community analysis, it is found that when the scale of scientists' cooperative network increases, the increase in the number of communities is not obvious, but the scale of each community will increase, and the probability of scientists belonging to overlapping communities will decrease. This shows that the increase in the number of authoritative scientists is not obvious after the unpopular research field becomes a popular research field. In hot research fields, the division of scientists' cooperation circles is clearer, and the cooperation frequency between circles will decrease significantly.
About some aspects of the organization of students individual work at pedagogical universities in the process of teaching classical optimization methods
Authors: Kuzmina N M , Samusenko P F , Kuzmin A V 
Published: June 2022

Abstract
Some aspects of teaching classical optimization methods to students of computer science specialties of pedagogical universities are described in the article. In Ukraine pedagogical universities the theory of optimization problems is most systematically considered in the course “Mathematical programming”. The paper presents the approximate topics of this course, analyzes the relevant interdisciplinary links, presents the main stages of solving applied optimization problems. The peculiarities of organizing the individual work of students who study according to the dual education system by using the elements of “flipped” learning are considered in the article. New approaches in the educational process with the using of the modern information technologies, in particular Maple computer math system, is demonstrated.
Interdisciplinary problems of mathematical content as a means of teaching programming to secondary school pupils
Authors: Bazurin V M , Chashechnikova O S , Karpenko Ye M , Pursky O I , Palchuk P M 
Published: June 2022

Abstract
The article discusses the main provisions of a practice-oriented approach to teaching programming in a school computer science course. The practice-oriented approach is implemented using a system of practice-oriented problems of mathematical content. The article reveals the classification of practice-oriented problems. Particular attention is paid to Interdisciplinary problems of mathematical content. The article describes the methodology, the main stages and the results of the experiment, during which the effectiveness of the system of practice-oriented problems of mathematical content in the process of formation of pupils’ ability to solve programming problems was tested. Using the methods of mathematical statistics, it was proved that the system of practice-oriented problems of mathematical content is more effective than the system of problems given in school textbooks on computer science. During the experiment, the influence of the system of practice-oriented tasks on the formation of pupils’ ability to solve programming problems was also investigated. It was proved that the use of the system of practice-oriented programming problems more effectively affects the formation of the ability to solve programming problems. For pupils of the experimental group, the differences between the initial level of formation of the ability to solve programming problems and the final level were significant, while for pupils of the control group, they were insignificant. The results of the experiment confirm the positive influence of the system of practice-oriented problems of mathematical content on the formation of pupils’ ability to solve programming problems.
Project-oriented approach to the study of robotics according to the concept of STEM education
Authors: Palchyk A O , Lutsyk I B , Burega N V 
Published: June 2022

Abstract
The importance of studying robotics in the conditions of the Fourth Industrial Revolution for solving the problem of training qualified STEM specialists is substantiated. The technique of using a project-oriented approach in the process of studying technologies for creating robotic systems is disclosed. The stages of implementation of the method based on the project of a maneuverable robotic platform are given. The methodology proposes a step-by-step development of a completed functional product, divided into several stages. At each stage, students get acquainted with the corresponding functions of the software and the theoretical aspects of electrical, physical, mechanical phenomena necessary to solve the problem at this stage. An important aspect of this technique is also the acquisition of practical work skills: drawing up diagrams, soldering individual electrical components to the board, laying electrical connections and manufacturing parts using 3D printing. Work on solving problem-oriented complex tasks allows to consider the problem as a collective, which will create the necessary prerequisites for professional activity. These capabilities of the project-oriented approach allow to implement the key concepts of STEM education: the research process, mastering the technology of manufacture and implementation of technical creativity on the basis of basic mathematical knowledge.
Proteolytic processes in organism of different age rats exposed to xenoestrogens
Authors: Lykholat T Y , Lykholat O A , Marenkov O M , Kvitko M O , Panfilova H L , Savosko V N , Belic Y V , Vyshnikina O V , Lykholat Y V 
Published: June 2022

Abstract
Endocrine disrupting chemicals (EDCs) are a group of compounds that affect the endocrine system, frequently found in everyday products and epidemiologically associated with several diseases. The human population is now ubiquitously exposed to EDCs in daily life. The main way of getting xenoestrogens to the body is the contaminated food. The effects of xenoestrogens on the proteolytic processes of different age rats were determination. The experiments were conducted on Wistar rats exposed to exogenous estrogen for 45 days. At the beginning of the experiment 3-month-old pubertal animals and 6-month-old sexually mature rats were involved. The research materials were organ tissue and blood serum of the rats. The objects were indexes of activity of trypsin and its obligatory inhibitors α1 - antitrypsin (α1-AT) and α2-macroglobulin (α2-MG), cysteine cathepsins B and L, the molecules of middle mass (MMM) level. In summary, the eating food contaminated by exoestrogens led to changes in the proteolytic system and the development of endogenous intoxication, which are also organ-specific and dependent on the age of the animals: a higher level of activity of the inhibitory link and the content of MMM was observed in rats in the puberty period, which leads to a decrease in the potential of the protective mechanisms of the organism and can become a trigger dysfunctional systems of natural detoxification and biotransformation. Inhibition of apoptosis is the main consequence found in the body of experimental rats. This phenomenon can lead to processes that inhibit one of the main mechanisms that reject damaged cells from the population. Females who were in puberty were more susceptible to dietary synthetic estrogens. In contrast to adult animals of the same sex, whose indicators indicate the importance of age characteristics of the body for the ability to perceive the effects of xenoestrogens. Rats became less sensitive to the effects of these substances with age. The diference in experimental animals was due to changes in the rate of detoxification pathway reactions, and not in the metabolism of estrogens entering the body, in particular, with food.
Quantum-mechanical approach to simulation of molecular crystals thermal conductivity
Authors: Pursky O I , Gamaliy V F , Demidov P G , Dyvak V V , Kozlov V V , Danylchuk H B 
Published: June 2022

Abstract
This article is devoted to the implementation of scientific achievements into the educational process of physics specialties students in the framework of study course “Solid State Physics”. In this work, based on our previous scientific results, we present a quantum-mechanical approach that can adequately describe the temperature dependences of the dielectric crystals thermal conductivity. The basic provisions of quantum-mechanical approach are studied by students in the framework of university study course “Solid State Physics” and are based on Einstein and Debye classical models. This approach is based on the assumption that in dielectric crystals heat is transferred due to the phonons (Debye model) and thermal diffusion between the thermally activated neighboring quantum mechanical oscillators directly from site to site on a time scale of one-half of the oscillation period (Einstein model). In term of this consideration the thermal conductivity of molecular crystals are simulated in the framework of thermal conductivity model where heat is transferred by low-frequency phonons with taking into account phonon–rotation coupling, and above the phonon mobility edge by “diffusive” modes. For this purpose the theoretical temperature dependences of the isochoric thermal conductivity have been calculated numerically in the interval near or over the Debye temperature and compared with experimental results for solid C6H12, CHCl3
and CH2Cl2. Using simple molecular crystals as an example it is shows the dualism of the nature of heat transfer processes in the temperature region of the order of the Debye temperature and above. The obtained results will be useful for implementation in the educational process in the study course “Solid State Physics” in particular for understanding the features of heat transfer in the high-temperature range of dielectric crystals existence.
Training of practicing teachers for the application of STEM education
Authors: Velychko V E , Kaydan N V , Fedorenko O G , Kaydan V P 
Published: June 2022

Abstract
The modern informational society poses new challenges to the education system, and one of the ways to solve them is STEM education, which has become one of the popular learning trends. The solution of the set tasks encourages not only the growth of the economic indicators, but also the general stable development of society with a careful attitude to resources, both material and immaterial. The practitioners are the leaders in high-tech changes of the education system, that is why they are the ones who can implement the STEM approach in the most effective way. This is important because the scientific component of technology is evolving over time and, accordingly, the skills of employees that are needed are changing, too. And the STEM approach in education, in turn, is the best to meet this requirement. The professional development of practicing teachers means to update knowledge in the field and acquire new teaching methods and technologies. Thus, in addition to professional necessity, professional development of practicing teachers is of innovative importance. The proposed certificate program of advanced training aims to develop students’ skills to implement STEM education in a scientifically sound and critical way; widely use interdisciplinary interaction; to introduce methods and means of STEM education in professional activity. The target audience of the program is future and practicing teachers of general and professional higher education.
Didactic fairy tale designing as a key to proactive training of Physics and Mathematics at primary schools
Authors: Kucheriavyi O H 
Published: June 2022

AbstractRelevance of the selected research topic is due to its development results aiming to resolve contradictions between society’s needs for personality-oriented training of Physics and Mathematics basics at comprehensive secondary school and the inadequate basic (necessary and sufficient) conditions to provide this in primary grades. Teachers also lack for a systematic and scientifically substantiated practice of immersing their students into the didactic fairytale environment. The research primarily aims to reveal the author’s conceptual vision of the essence and principles of didactic fairy tale designing in order to convert it into a basic tool of Physics and Mathematics training to 1st – 4th grade pupils.
Development and validation of the numerical model of Electron Cyclotron Resonance Ion Sources
Authors: Mironov V. , Bogomolov S. , Bondarchenko A. , Efremov A. , Loginov V. , Pugachev D. 
Published: June 2022

Abstract
Processes of the secondary electron emission (SEE) from the
walls are included into the Numerical Advanced Model of Electron
Cyclotron Resonance Ion Sources (NAM-ECRIS). It is found that SEE
strongly influences electron confinement time and ion
production. With the modified model, we observe reactions of the
source to changes in a gas flow into the source and in an injected
microwave power. The source performance with scaling the hexapole
magnetic field is investigated. The calculated tendencies are close
to the experimental observations.
Monte Carlo simulations of the electron — gas interactions in the KATRIN experiment
Authors: Kellerer J. , Spanier F. 
Published: June 2022

Abstract
At the KATRIN experiment, the electron antineutrino mass is
inferred from the shape of the β-decay spectrum of
tritium. Important systematic effects in the Windowless Gaseous
Tritium Source (WGTS) of the experiment include the energy loss by
electron scattering, and the extended starting potential. In the
WGTS, primary high-energy electrons from β-decay produce an
extended secondary spectrum of electrons through various atomic and
molecular processes including ionization, recombination, cluster
formation and scattering. In addition to providing data essential to
the simulation of energy loss processes, the electron spectrum also
provides information important in the simulation of plasma
processes. These simulations will then provide an insight on the
starting potential.

Here, a Monte Carlo approach is used to model the electron spectrum
in the source for a given magnetic and electric field
configuration. The spectrum is evaluated at different positions
within the WGTS, which allows for a direct analysis of the spectrum
close to the rear wall and detector end of the experiment. Alongside
electrons, also ions are tracked by the simulation, resulting in a
full description of the currents in the source.