bluuebunny/crossref_metadata_2025_split huggingface dataset:
Machine learning-based off-line electrical characteristic prediction through in-line pattern integrity inspection
Authors: Liu Ting-Jeng , Wu Meng-Jhu , Lo Cheng-Yao 
Published: November 2020

Abstract
In this study, an image inspection method was introduced to two-arm Archimedean spiral antenna patterns to quantify and qualify their in-line integrity, which was linked to their off-line electrical characteristics in terms of the capacitance values through machine learning. The pattern was intentionally deteriorated in shape to imitate potential fabrication variations existing in the microelectronic production line, and six physical features including the inner line edge roughness (LER), outer LER, integrated LER, inner arm length, outer arm length, and arm area were collected. Two groups of training and testing samples were simulated and fabricated. Based on Gaussian process regression with the covariance function in the form of a squared exponential, a model was developed to predict the capacitance values from the performances of the six features. The accuracy of the developed model was evaluated using the coefficient of determination and root-mean-square error. The results indicate that the developed model is capable of predicting the off-line electrical characteristics of microelectronic components based on their in-line pattern integrities. Advanced studies also reveal that although all LER values and arm lengths contribute to the electrical characteristics, the arm area is decisive.
Propagation of ultrasonic guided waves in plant leaves
Authors: Collazos-Burbano D A , Ealo Cuello J L , Villagrán-Muniz M 
Published: November 2020

Abstract
In this work, dispersive wave propagation in plant leaves is studied using a long distance laser-based ultrasonic method. Guided waves traveling through and along the midrib, as well as in the lamina, are measured and analyzed via wave attenuation, characteristic diagram and dispersion curves. Additionally, an estimation of the leaf elastic properties using the Rayleigh–Lamb model, supported by thickness-resonance frequency constraints, is proposed. This study paves the way for the development of acoustic fingerprints for the identification of leaves and their non-invasive and fairly non-destructive mechanical characterization, which is highly related to the plant hydraulics and photosynthetic activity.
Numerical investigation on the influence of circuit breaker structure parameters on vacuum arc behaviors
Authors: Zhao Lihua , Gou Hangyuan , Yang Mengjie , Hong Guo , Bai Xueyan , Huang Xiaolong , Ren Junwen , Ning Wenjun , Wang Lijun 
Published: November 2020

Abstract
In a switchgear, an external transverse magnetic field (ETMF) is generated by the U type loop consisting of the vacuum interrupter, external busbar and conductive rod connected to the vacuum interrupter. The ETMF will make the vacuum arc deflected and strengthen the contraction of the arc. This can increase the probability of breaking failure. To weaken the adverse effect of the ETMF, the real magnetic field data of the arc area with different structure parameters when the length of conductive rod, external busbar and phase distance is changed are obtained by establishing simulation model in this paper. Taking the real magnetic field data as the boundary condition, this paper obtains the typical parameters of the vacuum arc plasma with different structure parameters by using the established three-dimensional high-current vacuum arc magnetohydrodynamics model. The simulation results show that the ETMF makes the transverse magnetic field (TMF) of the arc area asymmetric, which leads to an arc deflection. Reducing the length of the conductive rod connected to the vacuum interrupter to 50 mm can effectively improve the asymmetry of the TMF caused by the EMTF, weaken the arc deflection phenomenon, make the distribution of the plasma parameters more uniform, and increases the utilization of the anode contact surface. Moreover, it can not only reduce the heat flux density into the anode as a whole, but also reduce the heat flux density in the high heat flux density area, so as to effectively reduce the degree of anode activity and improve the negative effects caused by the anode activity. The changes of other external structural parameters have less influence on the improvement of the vacuum arc deflection phenomenon. Increasing the phase spacing to 275 mm or reducing the length of the external bus bar to 100 mm can only slightly weaken the arc deflection.
A thermal-insensitive ultra-broadband metamaterial absorber
Authors: Bai Ningfeng , Zhong Fuxian , Shen Jingxuan , Fan Hehong , Sun Xiaohan 
Published: November 2020

Abstract
In this paper, a thermal-insensitive ultra-broadband metamaterial absorber (MMA) based on indium tin oxide (ITO) patterns and the SiO2 dielectric substrate is proposed to demonstrate high-temperature stability and excellent absorbability. The surface patterns consist of two different sizes of rectangular split-ring resonators with two gaps in each split-ring. Results from simulation indicate that at the initial temperature of 300 K, the relative absorption bandwidth reaches 83.35%, and the spectrum with absorptivity higher than 90% ranges from 8.00 GHz to 19.43 GHz. Moreover, in the temperature range of 300–700 K, the effective bands remain steady and cover more than 95% of the initial band. The simulation results also verify that the performance of MMA remains stable when exposed to high-intensity incident and high temperature of 500 K. The analysis of the surface current, electromagnetic (EM) field, power-loss density, equivalent circuit, and constitutive EM parameters reveals the mechanisms of thermal-insensitive ultra-broadband. This study expands potential applications of MMAs in conditions with thermal-stable demands.
Excited states in hydrogenated single-layer MoS2
Authors: Din Naseem Ud , Turkowski Volodymyr , Rahman Talat S 
Published: November 2020

Abstract
Our calculations of the excitation spectrum of single-layer MoS2 at several hydrogen coverages, using a density-matrix based time-dependent density-functional theory (TDDFT) show that the fully hydrogenated system is metallic, while at lower coverages the spectrum consists of spin-polarized partially filled localized mid-gap states. The calculated absorption spectrum of the system reveals standard excitonic peaks corresponding to the bound valence-band hole and conduction-band electron, as well as excitonic peaks that involve the mid-gap states. Binding energies of the excitons of the hydrogenated system are found to be relatively large (few tens of meV), making their experimental detection facile and suggesting hydrogenation as a knob for tuning the optical properties of single-layer MoS2. Importantly, we find hydrogenation to suppress visible light photoluminescence, in agreement with experimental observations. In contrast, both Li and Na atoms transform the system into an n-doped non-magnetic semiconductor that does not allow excitonic states.
Non-Hermitian generalizations of extended Su–Schrieffer–Heeger models
Authors: He Yan , Chien Chih-Chun 
Published: November 2020

Abstract
Non-Hermitian generalizations of the Su–Schrieffer–Heeger (SSH) models with higher periods of the hopping coefficients, called the SSH3 and SSH4 models, are analyzed. The conventional construction of the winding number fails for the Hermitian SSH3 model, but the non-Hermitian generalization leads to a topological system due to a point gap on the complex plane. The non-Hermitian SSH3 model thus has a winding number and exhibits the non-Hermitian skin effect. Moreover, the SSH3 model has two types of localized states and a zero-energy state associated with special symmetries. The total Zak phase of the SSH3 model exhibits quantization, and its finite value indicates coexistence of the two types of localized states. Meanwhile, the SSH4 model resembles the SSH model, and its non-Hermitian generalization also exhibits the non-Hermitian skin effect. A careful analysis of the non-Hermitian SSH4 model with different boundary conditions shows the bulk-boundary correspondence is restored with the help of the generalized Brillouin zone or the real-space winding number. The physics of the non-Hermitian SSH3 and SSH4 models may be tested in various simulators.
Numerical approach to optimizing the doping concentration of the absorber layer to enhance the performance of a CdTe solar cell
Authors: Sameera Jannatun Noor , Jhuma Farjana Akter , Rashid Mohammad Junaebur 
Published: November 2020

Abstract
Cadmium telluride (CdTe)-based solar cells have been proving their potential for high efficiency performance for several decades. However, efficient p-type doping of CdTe has remained a critical challenge for decades thus limiting the performance of this type of solar cell. Thus, this work intends to assess the effects of various dopants and their optimization in order to obtain efficient photovoltaic (PV) performances. In the process we used numerical simulation software SCAPS-1D as it expedites and facilitates the modeling of a solar cell through optimizations and variations. The studied CdTe solar cell structure comprises multi-junction semiconductor layers such as n-ITO/n-ZnO/n-CdS/p-CdTe in a superstrate structure. Three different types of absorber layer dopants such as copper (Cu), silver (Ag) and arsenic (As) are used, respectively. The work started with the optimization of carrier concentration followed by the variation of the thickness of the absorber layer. The PV performances in terms of open-circuit voltage, short-circuit current density, fill factor and efficiency are presented and, after comparison, the As dopant is shown to be a promising candidate. Also, the working temperature is varied to obtain a suitable environment under which the solar cell can work efficiently.
A magneto-active soft gripper with adaptive and controllable motion
Authors: Li Xianghao , Zhang Zheng , Sun Min , Wu Helong , Zhou Yisong , Wu Huaping , Jiang Shaofei 
Published: November 2020

Abstract
Bionic soft grippers that can gently conform to the objects of any profiles and softly hold them with uniform pressure have been receiving considerable attention. To realize rapid and non-contact driving, a novel magneto-active soft gripper is developed in this paper. The gripper is embedded with magneto-active elastomer (MAE) actuators that are made from a mixture of a soft material substrate and hard magnetic fillers. Firstly, the MAE actuators doped with different contents of magnetic fillers are manufactured and magnetized by applying an external magnetic field. An experiment is designed to measure the magnetically induced deformation of MAE actuators under different external magnetic fields. On basis of the experimental study of MAE actuators, the magneto-active soft gripper is then designed and successfully fabricated. The gripping function and efficiency of the magneto-active soft gripper is demonstrated through an experimental study. Meanwhile, the maximum gripping force of grippers is measured and the effects of applied magnetic field and mass faction of magnetic fillers are examined. It is found that the gripping force increases as either magnetic field strength or magnetic fillers’ concentration increases but tends to be stable when the magnetic field is greater than 80 mT. When executing a gripping motion, the magneto-active soft gripper has a significantly short response time than the existing ones with other driving methods.
Quantum dynamics of vibrational energy flow in oscillator chains driven by anharmonic interactions
Authors: Borrelli Raffaele , Gelin Maxim F 
Published: November 2020

Abstract
A new model of vibrational energy transfer in molecular systems taking into account anharmonic (third order) interactions of localized vibrations with a chain of harmonic oscillators is developed. The role of the energy spectrum of the chain and of the magnitude of the non-linear coupling is discussed in detail by an exact numerical solution of the quantum dynamical problem based on the tensor-train (matrix product state) representation of the vibrational wave function. Results show that the type of wave packet motion is determined by the eigen-spectrum of the chain and by its excitation time. It is found that when the excitation of the chain takes place on a much shorter timescale than the energy transfer along the chain the vibrational wave packet moves in a ballistic way independently of the length of the chain. On the other hand when the excitation of the chain takes place on the timescale of the energy transfer along the chain the overall motion becomes superballistic. These findings shed new light on recent observations of ballistic energy transfer along polymethylene chains.
Application of Kalman filter for prevention of unrequired operation of power transformer differential protection
Authors: Ivanchenko D I , Belsky A A , Dobush V S 
Published: November 2020

Abstract
As power transformers are core elements of electric power supply systems, transformer protection systems must reach high requirements. In order to reduce possible damage to transformers and prevent cases of false operations, resulting in interruptions of technological processes, protection devises with high sensitivity and high speed are required. This paper represents implementation of Kaman filtering theory with reduced calculation time for identification of faults in transformer from other transients. Parameters for tuning of Kalman filter for protection task and identification criteria were established. Operation of proposed algorithm was experimentally compared to Fourier transform based algorithm.
Research on acid and high-mineralized wastewater neutralization and purification process of the thermal power plant (TPP) ionite water treatment plants on laboratory stand
Authors: Yu Vlasova A , Vlasov S M 
Published: November 2020

Abstract
This paper presents the laboratory setup model for a treatment of acid sulfate-containing wastewater after regeneration of TPP water treatment plant (WTP) H-cation exchange filters. The model is based on the principle of acid wastewater neutralizing by alkaline slurry with further calcium chloride co-precipitation, which is the main component of highly mineralized TTPs wastewater. The wastewater slurry components analysis revealed that it consists of 80% calcium carbonate.
Approximation of hydraulic turbine performance characteristics using optimal splines and neural networks
Authors: Kovartsev Alexander , Nazarova Anastasia , Zakharchenko Vitaliy 
Published: November 2020

Abstract
The performance characteristic of hydrounits is used very often in various control systems on hydro power plant for velocity control, power distribution, for displaying at different levels of automation pyramid: technicians, technologists, management and so on. Different systems do not have single unified description of the hydrounit’s performance characteristic. It leads to growth of unnecessary calculations, errors and collisions. The study of the turbine efficiency can be automated by creating an appropriate mathematical model that approximates the initial performance characteristics of the turbine. This paper describes a method of approximation of the turbine performance characteristics using optimal two-dimensional cubic Hermit splines with free boundary conditions. The proposed method of hydrounit efficiency description allows to create single mathematical model and to use it in any control systems. The calculation load tests show high efficiency of the methods and confirm the possibility of their application in PLCs and servers.
FT-IR in situ thermoelectrochemical cell for electrode kinetics study
Authors: Kiselev N V , Artyukhov D I , Gorshkov N V , Burmistrov I N 
Published: November 2020

Abstract
The main parameter, that determines the use of thermoelectrochemical converters (TECC) for the waste heat harvesting is the efficiency of thermoelectric conversion. An increase of the current density at the electrode is possible due to the use of heterogeneous redox catalysts. In this paper, early results of Ti-based mineral catalysts usage are presented. A new type of thermoelectrochemical cell for in situ FTIR spectroscopy was designed, assembled and tested. With its use, the pattern of the redox reaction in

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Installation of wind turbines on the smoke stacks of power facilities
Authors: Ilyin R A , Shishkin N D 
Published: November 2020

Abstract
Currently, many works are devoted to the development of modern designs of wind power plants and improving the efficiency of existing ones. The work considered the issue of using wind energy by wind power plants, which are proposed to be installed on the chimneys of energy facilities. The original design of such an installation has been developed, which will allow using the phenomenon of free convection for its work even in the absence of an oncoming wind flow. The operation of the plant will partially or completely cover the costs of its own needs of the energy facility during its operation, which includes chimneys.
Interaction of temperature fields in an unlimited array of soil during the selection of low-grade heat by U-shaped probes of a geothermal heat pump units
Authors: Semenov B A , Saponenko D S , Dolotovsky I V , Pashchenko D I 
Published: November 2020

Abstract
The methodology and results of mathematical modeling of the unsteady process of selecting low-grade soil heat with a vertical U-shaped geothermal probe placed in a well of heat pump units (HPU), the free space of which is filled with a heat-conducting filler, are presented. The developed mathematical model is based on the joint use of two classical analytical methods: a source-drain adapted to the unsteady process of heat extraction from an unlimited soil mass, and a superposition method that allows one to quantify the effect of the interaction of the temperature fields of the downpipe and the riser pipe laid at a small distance from each other in one well. As a result, the main calculated dependencies underlying the developed mathematical model on which the computational experiment was performed were obtained analytically. The results of a computational experiment, performed on the example of a well with a vertical U-shaped soil probe, designed to select low-grade heat from an unlimited array of dry sand, are presented in graphs. An analysis of the results made it possible to identify the main factors affecting the intensity of heat extraction, justify the conditions for the effective operation of U-shaped probes in the wells of the soil contour of heat pump units, and quantitatively determine the maximum allowable temperature increment of the heated coolant according to the condition of efficient use of the heat transfer surface.
Development of a method for wireless information transmission in wells equipped with sucker rod pump units
Authors: Galeev A S , Arslanov R I , Suleymanov R N , Filimonov O V 
Published: November 2020

Abstract
Oil lifting via sucker rod pump units is the most widespread way to extract oil reservoir products. Complications adversely affecting the operation of downhole equipment and entailing increased wear and premature failure of sucker rod pump units arise in the process of high-viscosity oil production. The pressure and temperature of the well fluid are the main parameters for assessing changes in the properties of the extracted products and for determining the static level of the liquid column. It is possible to control pressure and temperature using sensors located in the immediate vicinity of the well pump. Today, a wired channel is the main way of transmitting the measured data to the well mouth. The present work proposes a new technical solution for a wireless communication channel along tubing strings and rods. The columns are separated by asphaltenes deposits on the surface of the columns and centralizers mounted on the rods. The rod string isolation from the tubing string at the wellhead is carried out through suspension modernization. Columns are closed inside the pump, specifically, on the cylinder-plunger contact. Information is transmitted from the bottom by means of a submersible module, consisting of an electrical separator and electronic circuit. The latter controls the separator closure and opening. The results of measurements of the resistance between the columns indicate the possibility of implementing a communication channel.
Information security management of enterprise mobile device
Authors: Omelchenko T A , Nikishova A V , Umnitsyn M Yu , Omelchenko I A , Umnitsyn Yu P 
Published: November 2020

Abstract
The development of the modern labour market involves increasing the level of mobility of personnel, so the current trend is the spread of mobile devices in the implementation of professional activities. This practice improves the efficiency of enterprise, but also has a negative impact on the security of information systems of enterprises. The growing requirements of employers have led to the growth of the functionality of mobile devices. However, this also causes an increase in the number of vulnerabilities in them, leading to an increase in the complexity of the security processes. The combination of the above problems determines the need to organize the process of information security management of enterprise mobile devices. The model of information security management of enterprise mobile devices is described in the article. It allows identifying vulnerabilities of operating system objects of enterprise mobile devices by modelling combinations of dangerous permissions more accurately.
An algorithm for selection of the preferable root switch for the spanning-tree protocol in computer networks
Authors: Rahman P A 
Published: November 2020

Abstract
This scientific paper deals with the computer networks based on the Ethernet technology and Spanning Tree Protocol (STP), as well as with the problem of selection of the root switch for the STP. The author offers an algorithm for selection of the preferable root switch for the STP based on the Floyd-Warshall algorithm for calculation of the shortest paths between all pairs of switches in a computer network. The algorithm for calculation of tree of the shortest paths for the given root switch is also overviewed. Finally, an example of the selection of the preferable root switch for the given network and calculation of tree of the shortest paths for the selected root switch is also presented.
Gesture identification in testing mode in the integrated sign language training system
Authors: Grif M G , Lukoyanychev A V 
Published: November 2020

Abstract
The structure of an integral sign language teaching system based on a 3D computer character, which allows demonstrating fingerprints and words of a sign language using an avatar, is considered. The system provides the test mode when the user must demonstrate the word or fingerprint indicated by the system. The user feedback with the system is carried out using a standard webcam. The problems of gesture localization and identification in user testing mode are considered. The features of this mode are determined during the system operation. The algorithm for quick identification of human hand gestures is proposed. The method based on the signs, which are two-dimensional projections, is used for gesture identification. The projection recognition features are considered, the similarity metrics are analyzed, and three stages for match decision are identified. The experimental results show the stable operation of this algorithm in various lighting conditions and at the place where the gesture was shown.