bluuebunny/crossref_metadata_2025_split huggingface dataset:
Magneto-optical characterization of ZnO / Ni nano-laminate obtained via Atomic Layer Deposition
Authors: Buchkov K , Galluzzi A , Blagoev B , Paskaleva A , Terziyska P , Stanchev T , Mehandzhiev V , Tzvetkov P , Kovacheva D , Avramova I , Nazarova E , Polichetti M 
Published: February 2021

Abstract
The magneto-optical (MO) properties of ZnO / Ni transition metal oxide (TMO) nano-laminate structures prepared by Atomic Layer Deposition (ALD) have been investigated. The structural (XRD) and chemical composition (XPS) analysis confirm the ZnO formation and corresponding effect of Ni incorporation in the crystal lattice. The XPS identification of Ni I2+ state, reveals also some minor traces of Ni(OH)2 inclusions. By using a MO Kerr effect microscopy, we have studied the local magnetic coercivity and its distribution and mapping of the ZnO/Ni nano-laminate sample on a microscale level. The statistical dispersion of the measured Hc
values ranges between 100 and 400 Oe (peak value of ∼ 200 Oe) with minor inhomogeneity inclusions.
Calculation of the Bandgap of Dilute Nitride GaAsSbN Alloys
Authors: Georgiev S , Donchev V , Milanova M 
Published: February 2021

Abstract
Dilute nitrides are semiconductor alloys, obtained from the conventional III-V compounds by incorporating a small amount of nitrogen. In this work, we focus on GaAsSbN considered as a perspective material for incorporation in multijunction solar cells. Nitrogen creates a localized level inside the conduction band continuum. The interaction of this level with the conduction band is usually described by the single band anti-crossing (BAC) model. The double BAC model of GaAsSbN considers both the N and the Sb localized levels in the conduction and the valence band, respectively. We calculate the bandgap energy of GaAsSbN employing the double BAC model for different concentrations of Sb and N. Parameters of the BAC model taken from different literature sources are used in the calculations and their influence on the final result is explored. Finally, the calculated bandgap energies are compared to experimental data of GaAsSbN layers grown on n-GaAs substrates by low-temperature liquid phase epitaxy. These data include the optical absorption edge of the material determined by surface photovoltage spectroscopy and the energy position of the photoluminescence peak at room temperature.
Development of a novel model for emptying of a self-pressurising nitrous oxide tank
Authors: Kardaś D , Szymborski J 
Published: February 2021

Abstract
Self-pressurised, or vapour pressurised system is a system that maintains operational pressure in ambient conditions, with no need for additional pressurisation. An example of such system is a tank filled with nitrous oxide, which keeps pressure of 50.35bar at 20°C. Self-pressurised tanks are used in hybrid rocket engines, due to low weight and simple construction. At the same time, accurate prediction of the dynamics of these systems during emptying creates a significant challenge, due to occurrence of near equilibrium two phase flow and rapid changes in pressure and temperature. The authors have developed several numerical models with aim of capturing described phenomena. The development started with basic assumption of lumped parameters approach and using mass and energy balance equations. First model featured two elements, one for the investigated fluid and second for the tank walls, with assumption of fluid in equilibrium, having single pressure and enthalpy. Such approach, while capturing major trends, lacked accuracy. To order to improve it, fluid was divided into two separate elements, one with saturated vapour and the second with the two-phase mixture. This proved to be more useful for predicting mass flow, but still did not offer accurate results. Further development included treating both fluid elements as two phase mixtures, first being mostly vapour and the second being mostly liquid and required additional equation describing tank’s internal dynamics. Resultant model allows for significantly higher pressure prediction accuracy than previously and gives better prediction of parameters of fluid flowing out of the investigated tank.
Modes for measuring aerodynamic resistances in the wind tunnel in the laboratory
Authors: Nedelcu O , Salisteanu I C , Magdun O , Dogaru V , Diaconu M 
Published: February 2021

Abstract
The paper is focused on the architecture and design of a wind tunnel for measurement of aerodynamical resistances. The quantities which influence the flow of fluids and the applied laws in this case are described on short. Taking into account the main criteria for wind tunnels classification (architecture, test chamber type, test chamber fluid speed) type of the tunnel will be chosen fallowed by the design and construction. Test chamber measurements are carried on by an anemometer. The physical results are compared with the modelling results obtained for ideal conditions with the aid of SolidWorks software.
Occurrence consequences of mining terrain surface discontinuous linear deformations in a residential building
Authors: Orwat J , Gromysz K 
Published: February 2021

Abstract
In the article a case study of consequences of underground mining exploitation of hard coal deposit on terrain surface and in a residential building has been presented. It was realized an exploitation of two hard coal seams (in three layers) in Poland, in the Upper Silesian Coal Basin, in 2013 – 2019. Operation was conducted at relatively small depth and by use of five longwalls with significant height and large decline. There were observed exploitation influences of fifth longwall on terrain surface and in the building by use of geodetic surveys. Measurements were carried out on the ground and wall points located in two perpendicular directions. Heights differences and distances between next points before and after the end of exploitation of last longwall have been measured. There the inclinations changes of particular sections have been determined. Analysis of surveys results shown that processes of the terrain and buildings deformations take place differently and terrain inclinations and building deviations have other values. Moreover, next to the building four discontinuous linear deformations of terrain surface (one in front of the building, one under the building, two behind the building) have been occurred. The ground steps location was detected by use of profile leveling of road located on the east of the building. A ground step with height of 15 cm under the building caused its crack. Example of the building with a partial basement proved that a consolidation type of building in the ground has a significant influence on values of its deviations.
Determination of the discretion interval of the temporal series of the technological process parameter measurement in ACS TP in the noises conditions
Authors: Tymchuk S O , Abramenko I G , Zahumenna K V , Miroshnyk O O , Shchur T G , Tomporowski A , Kruszelnicka W 
Published: February 2021

Abstract
We have solved the problem of substantiating the choice of the sampling interval of the temporal series of the technological process parameter measurements for automation systems, if there are errors, which takes into account the frequency characteristics of this series. The object of the study is the measuring channel of ACS TP (automated control systems of technological processes). We have developed the mathematical simulation model of the measuring channel and the analog-to-digital converter, which provides the possibility of studying the influence of the sampling interval value of the temporal series of technological process parameter measurements on the reliability of the information. The results of the research of the model show the effectiveness of the model developed.
Scheduling of preventive maintenance of an power equipment of the agricultural enterprises
Authors: Trunova I , Miroshnik O , Savchenko O , Moroz O , Pazyi V , Shchur T , Kasner R , Bałdowska-Witos P 
Published: February 2021

Abstract
Presented paper deals with the topic of preventive maintenance of an power equipment of typical agricultural enterprises. A decision support method was designed, incorporating the analysis of annual schedules of load diagrams of the typical agricultural enterprises and the planning of preventive maintenance of the power equipment with month priority during which maximal consumption of electric energy take place. The correction of typical load diagrams on the basis of the fact sheet about electric loading of the consumer is possible. The designed method optimizes maintenance costs without supplementary investment and running costs. An algorithm of the designed method is offered and a case study of its implementation is described in the paper.
Asymmetry bandwidth of stock market index time series as a warning signal
Authors: Malivuk Gak D , Rajilic Z , Stupar N 
Published: February 2021

Abstract
The time series of the S&P 500 index from 2003 to 2018 and the stochastic time series are considered. The asymmetry is called the change in the complexity Cmp of the time series when time direction is changing, and the values of the asymmetry of the substrings are in the interval of a certain width. The asymmetry bandwidth of the S&P 500 series is minimal for 2005, and stochastic strings can have such a small width. The 2007-2008 crisis seems to have been preceded by a rush of heightened stochasticity (a fall in predictability) that has led to a decline in investor optimism. By calculating asymmetry bandwidth, a warning signal could be obtained for a possible stock market crash.
Analysis of voice control of a collaborative robot
Authors: Janíček M , Ružarovský R , Velíšek K , Holubek R 
Published: February 2021

Abstract
Using the voice control to interact with things around us can always be one of the most interesting things. Voice control is becoming more and more used in everyday life, whether it is a smart home, voice control of a mobile phone or voice control of comfort equipment in a car. Whether, voice control gets into the production industry line is the right question. Reliability is still insufficient. The paper is focused on analysis of voice control of a collaborative robot. Analysis is focused on various voice commands, their repeatability and reliability in robot-human cooperation. The research determines the most problematic voice commands and ideal voice commands for voice control of a collaborative robot.
Development of the fundamental diagram of the formation and transformation of the products properties during their manufacturing
Authors: Kusyi Y M , Stupnytskyy V V , Kuk A M , Topilnytskyy V G 
Published: February 2021

Abstract
In object-oriented technologies of mechanical engineering production the step-by-step execution of interconnected design stages of technological process of product manufacture is used. A systematic approach to research and qualitative modelling of real physical processes, taking into account the operational characteristics of products and machines at all levels of research is ignored. As a rule, the object-oriented technological processes do not track the change of the products properties during their manufacture from the position of technological inheritability for all stages and substages of the Life Cycle Support of Product. Therefore, the development of scientific and applied principles of technological inheritability of quality parameters to provide the operational characteristics of products in the design of function-oriented technologies is a priority item of modern mechanical engineering. The structure of functional-oriented technology is closely related to the stages and substages of Life Cycle Support of Product. From the standpoint of continuous damage mechanics, Life Cycle Support of Product is considered to be a single process of exhaustion of the material plasticity margin under the influence of certain load modes in accordance with the technological inheritance of the product properties. The basic chart of the formation and transformation of the products properties from the point of view of mechanics of technological inheritability is developed. This chart, in contrast to previous research in this area, takes into account the significant impact of the stage of blanks manufacture in the technological process structure on the formation of technological parameters and operational characteristics of products.
Analysis of the Industry 4.0 key elements and technologies implementation in the Festo Didactic educational systems MPS 203 I4.0
Authors: Ružarovský R , Holubek R , Janíček M , Velíšek K , Tirian G O 
Published: February 2021

Abstract
Industry 4.0 is one of the key words and strategies in current industrial production. It is important to define the Industry 4.0 strategy, analyse its objectives, and characterize the key elements and technologies of Industry 4.0. The Industry 4.0 concept uses the Industry 4.0 reference architecture, which assists and guides automated system developers in their design and construction, and of course in the development of a new assembly product. Given that the existing assembly system for education - Festo Didactic MPS 203 I4.0 is used to explore the possibilities of using digitization in design, it will be necessary to analyse this system in terms of reference architecture and key elements of Industry 4.0 implemented. The result is in conclusion of how deeply the key elements of Industry 4.0 are implemented in this educational system. The aim of this result was to create a digital twin of the system and test it in a virtual environment after the verification and validation of the digital twin model.
Dual Stator Winding Induction Generator (DSWIG) used for hybrid micro grid power systems
Authors: Topor M , Deaconu S I , Bu F , Popa G N , Tutelea L N , Muntean N 
Published: February 2021

Abstract
This paper proposes a hybrid micro grid system for critical consumers like military disaster intervention, health or municipality. The solution is based on a multiple level of redundancy DC micro grid. The solution is projected to provide critical functionalities like stability, power quality, coordinated control, grid support capability. The configuration described here takes in consideration the problem integration of renewable energy sources which should have features like redundancy, flexibility and scalability from architecture point of view.
Tuning proportional-derivative controller for a three-phase electric arc furnace
Authors: Ghiormez L , Panoiu M , Panoiu C , Muscalagiu I 
Published: February 2021

Abstract
In this paper is presented a control system that is based on the proportionalderivative controller for modeling and simulation of the electric arc furnace focusing on the controller’s loop. The proposed controller is used to modify the position of the electrodes of the electric arc furnace in order to minimize the effect of the disturbances that can appear in the process during its functioning. With the proposed controller can be obtain the maximum power that can be used during functioning of the electric arc furnace. Also, the proposed control system can be used to obtain a specific active power for the electric arc that appears in the functioning of the electric arc furnace. In this paper are presented the steps used to tune the proportional and derivative gains of the controller. Used mathematical model of the electric arc is based on the voltage-current characteristic of the electric arc that simulates the functioning of the electric arc from the electric arc furnace. The model is integrated in the control system implementation. The simulations are implemented using Simulink toolbox from Matlab software. Taking into consideration obtained results during simulation are selected the best values for the gains of the proportional-derivative controller in order to obtain performance optimization of the electric arc furnace. For the selected gains of the proportional-derivative controller is presented the response of the system that is tested in a closed loop.
Some aspects regarding the implementation of a Web application in different SAP UI technologies
Authors: Berdie A D , Berdie A A , Lemle K L 
Published: February 2021

Abstract
Currently, in the development and implementation of an web application, the software developers are turning to those technologies that satisfy the client’s requirements, that can be easily extended and have optimal results in terms of execution time. This scientific paper addresses issues related to the development and implementation of the same application using three different web technologies, existing on the SAP NetWeaver platform. In this context, aspects related to the SAP NetWeaver technological platform and the SAP AS application server ABAP, the facilities offered by these for developing and implementing web applications, as well as the features specific to Web Dynpro ABAP, Floorplan Manager and WebClient UI technologies are highlighted.
Sea ice impact on naval operations
Authors: Novac V , Rusu E , Onea F , Stăvărache G 
Published: February 2021

AbstractThis paper highlights the icing regime and its impact on the primary naval operations conducted in the Black Sea basin. The article analyzes seawater’s phenomenon freezing through the perspective of merchant shipping operations and underlines the impact on undersea or surface warfare. The article figures out the impact on the ship hull, weapons systems, personnel, as well as the tactics aspects of operations or de-icing strategies when ice accrues on ship hull and equipment. The article points out associated meteorological phenomena and brings in attention the importance of meteorological and oceanographic observations in situ or by satellites as a condition for the success of the operation. In the end, the article concludes regarding shortfalls faced during icing periods and give some directions meant to curb the adversary effects of unfavorable icing environment.
The analysis of the deforming regime in the electric traction railway
Authors: Baciu I , Cunţan C D 
Published: February 2021

Abstract
The paper presents the results of measurements of electric power quality analyzer CA8334 on an electric locomotive equipped with continuous power engines. Determinations were made of the arrangements of current and voltage related to a motor of a locomotive 5 MVA. The data measured by the analyzer were transferred to a computer system using the Qualistar program and further processed in Excel that allows graphical representation of the characteristic quantities of power quality.
Management of the activity of quality assurance of cast iron castings in foundries
Authors: Josan A , Ardelean E , Ardelean M , Puţan V 
Published: February 2021

Abstract
In Romania, at present, the process of casting the parts is used under different methods. Thus, castings have different configurations and are used in various fields of technology, such as for the automotive industry, motorcycles and engines, electrical and electronics, space, computing and office equipment, agricultural machinery, aeronautics, woodworking or household industry. There is also a wide variety of materials used in casting these types of castings. The quality of the castings is found in the final product and, therefore, a special importance is attributed to the management activity to ensure the proper management of all processes in the foundry. For this, methods, techniques and management tools are used and applied so as to continuously optimize processes and activities and to be in accordance with the objectives of the system, respectively the continuous quality assurance and customer satisfaction. The paper presents the possibility of obtaining the quality of vermicular graphite cast iron castings, of the gate valve type.
Impact of contaminants on engine oil: a review
Authors: Raţiu S , Josan A , Alexa V , Cioată V G , Kiss I 
Published: February 2021

Abstract
Contaminants in engine oil alter its structure in different ways, depending on their nature, leading to the degradation of the lubricant and, if it is not replaced in time, even to loss of engine performance and its failure. Consequently, both for environmental reasons and from an economic point of view, it is important to be aware of the danger that these substances may present. This paper offers an investigation of the engine oil contaminants in general, emphasizing the most dangerous ones. It also includes the causes that contribute to their appearance, the types of contaminants, the way they act, the processes that result from contamination and the impact they have on engine components.
The 3D reconstruction of a road accident used the specialized program PC Crash 12.1
Authors: Dascăl A , Popa M 
Published: February 2021

Abstract
A modern tool used in conducting forensic and extrajudicial technical expertise is the program specialized in simulating PC-Crash road traffic accidents, which covers a multitude of different situations, as it benefits from the advantages of the latest achievements in the fields of hardware and software. The paper presents one of the possibilities of the PC Crash program for computerized reconstruction of the dynamics of a road accident, by correlating the physical possibilities of the accident, based on the laws of mechanical engineering.
Processing of ferrous iron and steel waste in the context of the circular economy
Authors: Lupu O , Socalici A , Popa E , Gaianu O 
Published: February 2021

Abstract
The paper presents the possibilities of exploiting the small and powdered ferrous waste with the production of lighters that can be used as a raw material in the loading of the steel processing units. The capitalization of small ferrous and powdered iron and steel wastes is an important problem, because their transformation into by-products, so in economic goods can lead to a rational exploitation of the resources of raw materials and energy, thus ensuring both the needs of the human society and the protection of the environment surrounding.
Turning a waste producer into an energy producer
Authors: Halmaciu A I , Wächter M R , Ionel I 
Published: February 2021

Abstract
The paper focuses on the possibility to turn waste generated by farms into biogas, which can be used for electricity and heat generation, covering own use or even more. Three case studies, all based on experiments, are presented, the first two revealing data concerning the potential energy development from the waste, as energy carrier, the third, run on a very modern lab facility, demonstrating the high potential of the manure as renewable bio-energy source. All are based on anaerobic biogas production.
The importance of indoor air quality (IAC) monitoring
Authors: Corlan R V , Balogh R M , Ionel I , Kilyeny St 
Published: February 2021

Abstract
Air pollution is already a global public health crisis, as it kills seven million people each year, according to the World Health Organization. Presently, a correlation between health and air pollution levels recorded in the past exists. The paper presents series of instruments concerning IAC (Indoor Air Quality) measurements and focuses on indoor air quality measurements taken in different closed spaces, as example. Based on the concentration values detected, the conclusion of the paper indicates that, depending on the technological process or activity in enclosed spaces, it is mandatory to check the IAQ. This action must be taken as prevention, in order to reduce potential health risks upon humans, acting in their homes, or schools and offices or industrial halls, in general in closed spaces, even when artificially ventilated.