bluuebunny/crossref_metadata_2025_split huggingface dataset:
Multi-scale simulation of the dendrite growth during selective laser melting of rare earth magnesium alloy
Authors: Wang Wenli , Liu Wenqiang , Yang Xin , Xu Rongrong , Dai Qiuyun 
Published: December 2021

Abstract
The solidification microstructure of the alloy fabricated by the selective-laser-melting (SLM) process can significantly impact its mechanical properties. In this study, a multi-scale model which couples the macroscale model for thermal-fluid and microscale cellular automata (CA) was proposed to simulate the complex solidification evolution and the dendrite growth (from planar to cellular to dendritic growth) during the SLM process. The solid–liquid interface of CA was dispersed with the bilinear interpolation method. On that basis, the curvature was accurately determined, and the calculation result was well verified by employing the Kurz–Giovanola–Trivedi analytical solution. The dendrite morphology, solute distribution, and primary dendrite arm spacing during the solidification of the SLM molten pool were quantitatively analyzed with the proposed model, well consistent with the experiment. The distribution of the undercooling field and the concentration field at the tip of dendrites different orientations were analyzed, and the two competing growth mechanisms of converging and diverging growth were revealed. Moreover, the research also indicates that during the growth of dendrites, the result of dendrite competition is determined by the height of the dendrite tip position in the direction of the thermal gradient, while the distribution of the concentration field (symmetrical or asymmetric) at the tip of the dendrite critically impacted the competing growth form of dendrites.
Algorithms for solving high dimensional PDEs: from nonlinear Monte Carlo to machine learning
Authors: E Weinan , Han Jiequn , Jentzen Arnulf 
Published: December 2021

Abstract
In recent years, tremendous progress has been made on numerical algorithms for solving partial differential equations (PDEs) in a very high dimension, using ideas from either nonlinear (multilevel) Monte Carlo or deep learning. They are potentially free of the curse of dimensionality for many different applications and have been proven to be so in the case of some nonlinear Monte Carlo methods for nonlinear parabolic PDEs. In this paper, we review these numerical and theoretical advances. In addition to algorithms based on stochastic reformulations of the original problem, such as the multilevel Picard iteration and the deep backward stochastic differential equations method, we also discuss algorithms based on the more traditional Ritz, Galerkin, and least square formulations. We hope to demonstrate to the reader that studying PDEs as well as control and variational problems in very high dimensions might very well be among the most promising new directions in mathematics and scientific computing in the near future.
Locating Ruelle–Pollicott resonances*
Authors: Butterley Oliver , Kiamari Niloofar , Liverani Carlangelo 
Published: December 2021

Abstract
We study the spectrum of transfer operators associated to various dynamical systems. Our aim is to obtain precise information on the discrete spectrum. To this end we propose a unitary approach. We consider various settings where new information can be obtained following different branches along the proposed path. These settings include affine expanding Markov maps, uniformly expanding Markov maps, non-uniformly expanding or simply monotone maps, hyperbolic diffeomorphisms. We believe this approach could be greatly generalised.
Global attractivity for a nonautonomous Nicholson’s equation with mixed monotonicities
Authors: Faria Teresa , Prates Henrique C 
Published: December 2021

Abstract
We consider a Nicholson’s equation with multiple pairs of time-varying delays and nonlinear terms given by mixed monotone functions. Sufficient conditions for the permanence, local stability and global attractivity of its positive equilibrium K are established. The main novelty here is the construction of a suitable auxiliary difference equation x

n+1 = h(x

n
) with h having negative Schwarzian derivative, and its application to derive the attractivity of K for a model with one or more pairs of time-dependent delays. Our criteria depend on the size of some delays, improve results in recent literature and provide answers to open problems.
Parallel control model for navigation tasks on service robots
Authors: Montiel Holman , Martínez Fernando , Martínez Fredy 
Published: December 2021

Abstract
Autonomous mobility remains an open research problem in robotics. This is a complex problem that has its characteristics according to the type of task and environment intended for the robot’s activity. Service robotics has in this sense problems that have not been solved satisfactorily. These robots must interact with human beings in environments designed for human beings, which implies that one of the basic sensors for structuring motion control and navigation schemes are those that replicate the human optical sense. In their normal activity, robots are expected to interpret visual information in the environment while following a certain motion policy that allows them to move from one point to another in the environment, consistent with their tasks. A good optical sensing system can be structured around digital cameras, with which it can apply visual identification routines of both the trajectory and its environment. This research proposes a parallel control scheme (with two loops) for the definition of movements of a service robot from images. On the one hand, there is a control loop based on a visual memory strategy using a convolutional neural network. This system contemplates a deep learning model that is trained from images of the environment containing characteristic elements of the navigation environment (various types of obstacles and different cases of free trajectories with and without navigation path). To this first loop is connected in parallel a second loop in charge of defining the specific distances to the obstacles using a stereo vision system. The objective of this parallel loop is to quickly identify the obstacle points in front of the robot from the images using a bacterial interaction model. These two loops form an information feedback motion control framework that quickly analyzes the environment and defines motion strategies from digital images, achieving real-time control driven by visual information. Among the advantages of our scheme are the low processing and memory costs in the robot, and the no need to modify the environment to facilitate the navigation of the robot. The performance of the system is validated by simulation and laboratory experiments.
Optimization of an automatic voltage regulator AVR on a synchronous machine using fuzzy control
Authors: Cuesta Diego N Cuesta , Martínez Santa Fernando 
Published: December 2021

Abstract
The constantly developing society demands more and more electronic devices and microchips that perform vital tasks such as medical services, emergency lighting, communication systems, among others, however these are sensitive to variations and failures of the power supply, such as voltage fluctuations, voltage spikes and interference, for this reason and because of its great importance for its proper functioning must have a continuous power supply, Thus, the work shown in this article proposes to optimize the operation of automatic voltage correction devices AVR used in synchronous power generating machines whose main function is to ensure that the voltage has been constant, for this a solution is proposed based on the use of non-traditional control techniques such as fuzzy logic, For this purpose initially recognizes the relevant elements that make up the AVR system which are amplifier, exciter, generator and sensor then illustrates the mathematical block model that represents the operation of the system which is reduced to transfer function or otherwise as the relationship of the input and output signal of the system, Then a possible classical PID proportional integral derivative proportional control is suggested with the help of the PID tools of the software Matlab ®, where the fuzzy logic inference set is programmed in three stages: first stage: input of the set of rules for voltage error correction, second stage: input of the set of rules for the voltage field output in the synchronous machine, and in a third stage: programming of the fuzzy inference sentences. Finally, the response of each control is compared and the methodology in the design of the alternative control in the synchronous machine is exposed, with the use of the software Matlab®, all this as a study of new trends in control for educational purposes, in the context of Technology in Electricity and Electronic Technology.
Equation of lightning return current in tropical zones
Authors: Rubiano-Cruz J , Páez-Moncaleano S , Chacón-Cardona C , Torres-Sánchez H 
Published: December 2021

Abstract
The purpose of this study is to model mathematically the equation of the lightning return current in tropical zones and to validate it with data obtained from direct measurements in Colombia and Brazil. This study is carried out because the lightning return current in tropical zones is greater than in other latitudes of the planet. For this reason, it is very important for different applications in electrical engineering. Nowadays, the Heidler equation is used for the simulation of faults in electrical systems. This equation will serve as a reference to make a comparison between the data of the equation obtained in this article with those from the equation of Heidler.
Black hole optimizer for the optimal power injection in distribution networks using DG
Authors: Montoya Oscar Danilo , Giral-Ramírez Diego Armando , Grisales-Noreña Luis Fernando 
Published: December 2021

Abstract
The optimal sizing of Distributed Generators (DG) in electric power distribution networks is carried out through a metaheuristic optimization strategy. To size DG it is proposed an optimal power flow model is formulated by considering that the location of these sources has been previously defined by the distribution company. The solution of the optimal power flow is reached with the Black Hole Optimizer (BHO). A methodology is used master-slave optimization methodology, where the BHO (i.e., master stage) defines the sizes of the DG and the slave stage evaluates the objective function with a load flow algorithm, this work using the triangular-based power flow method. Numerical results in the 33-node and the 69-node test system demonstrates the effectiveness and robustness of the proposed approach when compared with literature results.
Design of Central Air Conditioning Control Acquisition Device Based on IoT Technology
Authors: Huang Changwei 
Published: December 2021

Abstract
With the rapid development of Internet and electronic technology, the Internet of things (hereinafter referred to as IOT) has become an important way of many intelligent devices, which can improve people’s application of intelligent devices. Through the IOT, we can carry out the research on the centralized monitoring system of central air conditioning [1]. Through the IOT, we can realize the IOT of indoor and outdoor units of central air conditioning, which can realize the important application of practical engineering projects. Through fuzzy algorithm, this paper can improve the overall improvement of the project. Through the cooperation of MCU and GPRS module, we can complete the wireless transmission of data., This can realize computer terminal monitoring and mobile terminal monitoring. Through engineering application, we can realize the automation and information integration of system monitoring, which will greatly improve the monitoring efficiency. Through the development of acquisition device, we can improve the comfort and security of central air conditioning, which will enhance the communication between the physical equipment of the system and the upper server network. Firstly, this paper analyzes the flow of fuzzy PID algorithm. Then, this paper specifies the system diagram of the central air conditioning control acquisition system [2]. Finally, this paper puts forward the important work of system acquisition.
Intelligent Agricultural Automatic Control System Based on Internet of Things
Authors: Wu Yongtang 
Published: December 2021

Abstract
The advanced technology of the Internet and extensive agricultural transformation and upgrading have made the overall agricultural industry chain and modern agriculture better. In view of the high cost and suffering of traditional agricultural planting management, the Internet of Things (I O T) is applied to agriculture to realize real-time detection and intelligent management of crop growth conditions, remote control, and change the traditional agricultural equipment planting mode. The purpose of this article is to design and research the I O T automatic control (A C) system for smart agriculture. This article first introduces the core technology of the I O T through an overview of the basic theories of the I O T. Combined with the current status of agricultural automation in my country, the existing problems and deficiencies are analyzed. On this basis, use the core technology of the I O T to supplement and improve it. This article systematically expounds the overall scheme design, module function design and A C algorithm realization of the I O T brake control system. And use field investigation method, comparative analysis method and other research forms to carry out research on the theme of this article. Experimental research shows that the sampling data of the greenhouse is selected as the sample, the appropriate initial membership function is selected, and the fuzzy control rules obtained through the training of the fuzzy neural network algorithm are relatively correct. The output result of the automatic temperature control system is mostly consistent with the actual data on site. Overall, the temperature A C system designed in this subject can meet the A C requirements of agriculture.
Design of General Test System for Optoelectronic Equipment Based on Computer
Authors: Han Xuefeng 
Published: December 2021

Abstract
In recent years, with the popularization of optoelectronic equipment in various industries, various reconnaissance equipment and test equipment have also appeared. Traditional test technology and system functions can no longer meet the development of optoelectronic equipment, so it is imperative to introduce general test ideas and establish a general test system.
Artificial Intelligence Technology in Optical Fiber Communication Engineering
Authors: Gao Demei 
Published: December 2021

Abstract
Optical fiber communication engineering as a kind of “wired” optical communication mode which uses light wave as carrier and optical fiber as transmission medium to transmit information from one place to another, especially optical fiber has a special position in the communication industry due to its unique advantages of wide transmission frequency band, high anti-interference and small signal attenuation. It has important practical value for the deep research of the area setting and protection of optical fiber and cable in the optical fiber communication engineering. However, at present, there is no complete management system in the aspects of hardware processing, fiber optic cable protection and the guarantee of the introduction of related talents, so it is urgent to innovate and develop the existing path. Based on this, this paper first analyzes the problems of optical fiber guarantee in the intelligent technology system construction of optical fiber technology in the field of communication engineering, and then puts forward the construction strategy of intelligent protection and breakthrough technology in optical fiber communication technology system.
Big Data Technology in Intelligent Management and Control System of Drainage Pipe Network
Authors: Hu Su , Zhang Wanhui 
Published: December 2021

Abstract
With the rapid development of urban construction, smart city has become an important trend in the future, which is inseparable from the intellectualization of drainage pipe network. At the same time, with the increasing frequency of urban flood disasters, the old drainage pipe network system will cause significant economic losses, which requires modern cities to establish intelligent management and control of drainage pipe network. However, the situation of drainage facilities in most cities in China is complex, which requires strengthening modern means such as monitoring, operation management and planning services. Therefore, the research on intelligent management and control system of drainage pipe network based on big data technology is of great significance. Firstly, this paper analyzes the importance of intelligent management and control system. Then, this paper puts forward the main algorithms for big data processing. Finally, this paper constructs the intelligent management and control system of drainage pipe network.
Plane Visual Communication Design of User Experience Effect Based on Computer Simulation
Authors: Zhang Fang , Li Mingjiong 
Published: December 2021

Abstract
With the development and popularization of computer simulation technology, its application in all walks of life has become more and more extensive, and it has also effectively promoted the development of all walks of life. This article analyzes the elements of flat visual communication design, and it decomposes the multi-level structure of user experience effects in flat visual communication design. In addition, the design of plane visual communication requires the aid of a three-dimensional reconstruction system, so this paper also studies the hardware design and software design of the three-dimensional image virtual reconstruction system.
On-line Measurement Method and Technical Scheme of Transmission Line Crossing Point Based on Machine Vision
Authors: Tang Jie , Huang Zhidu , Cui Zhimei 
Published: December 2021

Abstract
With the increasing demand for high voltage and UHV transmission, higher and higher requirements are put forward for transmission line monitoring and fault diagnosis. The traditional line measurement method has many shortcomings, which cannot ensure the measurement accuracy, measurement efficiency and high cost. Based on this, this paper first studies the principle of machine vision on-line measurement, then analyses the on-line measurement process of transmission line crossing point based on machine vision, and finally gives the error source and amelioration measures of transmission line crossing point on-line measurement.
Smart Meter Evaluation System Based on Big Data
Authors: Zhou Yu , Shao Xuesong , Mu Zhuowen , Cai Qixin , Li Yue , Gao fan 
Published: December 2021

Abstract
Aiming at the problem of unstable operation of smart meters, this paper proposes a smart meter evaluation system based on big data. First introduce big data related technologies, such as data storage, analysis, mining, etc.. Secondly, design the big data smart meter evaluation system model. Finally, use big data technology and clustering algorithm to realize the design of the big data smart meter operation evaluation system. The system can convert massive data from multiple systems into operational evaluation reports, which helps to reduce the waste of human and material resources.
Influence of Numerical Control Cutting Parameters on Performance of Numerical Control Tool
Authors: Sha Heng 
Published: December 2021

Abstract
As China has stepped into a new era of development, the popularity of computer applications is becoming more and more profound. Especially in the machinery manufacturing industry, the current market has put forward a higher requirement for the accuracy and toughness of machinery manufacturing, and the traditional artificial manufacturing has not been adapted to the development of the industry. Through numerical control technology, numerical control tool manufacturing process can become very standardized, its accuracy and toughness is also guaranteed. This paper will from the numerical control this point of view, to explore the influence of numerical control cutting parameters on the numerical control tool.
The applying of the short — term cross correlation in optical diagnostics of melt convection in laser metal deposition
Authors: Zavalov Y N , Dubrov A V 
Published: December 2021

Abstract
The time dependences of the surface temperature and the surface area of the melt bath during the formation of the single track in the laser metal deposition technology were obtained using a multi-wave optical diagnostics complex. The short - term cross-correlation method was used to analyse the measured parameters of the bath surface, and relationship of the measured parameters with the processes of thermocapillary convection in the melt was shown.
Electrochemical deposition of ceramic-like coatings on Ti-6Al-4V parts fabricated by electron beam melting
Authors: Peretyagin N Y , Suminov I V , Smirnov A , Krikheli N I , Kramar O V , Peretyagin P Y 
Published: December 2021

Abstract
The problems of micro-arc oxidation of titanium alloy parts Ti-6Al-4V produced by electron beam melting technology were considered. The phase composition, thickness and roughnessof the obtained coating have been evaluated.
Plasma and photon technologies against bio-factors, dangerous to human being
Authors: Volpian O D , Dronsky R V , Obod Yu A , Kuzmichev A I , Andrienko O V , Alybin K V 
Published: December 2021

Abstract
Possible plasma and photonic methods and devices for monitoring and preventing dangerous infections and human diseases are presented. In experiments with different types of atmospheric pressure discharges in different gases, the significant bactericidal effect was found. The prototype of device based on the method of absorption spectroscopy for detecting human diseases by biomarkers in the exhaled air has been proposed and tested. The importance of the plasma technology of deposition of coatings by magnetron sputtering for the creation of anti-covid masks and high-quality optics (mirrors) for photon monitoring devices is emphasized.
Cathodic nitriding and anodic polishing of Ti6Al4V alloy by plasma electrolysis
Authors: Tambovskiy I V , Vdovichenko R A , Belov R D , Dyakonova A D , Nikiforov R V , Silkin S A , Kusmanova I A 
Published: December 2021

Abstract
The paper presents the results of studies on modifying the surface of Ti6Al4V titanium alloy by combined exposure to cathodic nitriding and anodic polishing in electrolysis plasma. The morphology and roughness of the surface, microhardness of the modified layer have been investigated. Wear resistance was studied under dry friction conditions. The effect of combined treatment on corrosion resistance of Ti6Al4V alloy was examined by means of potentiodynamic polarization in Ringer’s solution. It has been established that cathodic nitriding at 750 °C for 10 min leads to the hardening of the surface layer up to 820 HV with an increase in roughness by 2 times and wear resistance almost 3 times. Subsequent anodic plasma electrolytic polishing of the nitriding surface in solution of ammonium sulfate leads to a decrease in roughness and friction coefficient with an increase in corrosion resistance.