bluuebunny/crossref_metadata_2025_split huggingface dataset:
Field test on engineering characteristics of karst breccia
Authors: Yin Xiansong , Xie Liming , Feng Mingquan , Wang Song 
Published: February 2021

Abstract
Karst breccia is a special kind of rock related to karst action with wide distribution. The karst breccia in the dam site area of a hydropower station in the Three Gorges reservoir is very representative. Field tests are carried out on the karst breccia at the dam site of the hydropower station, including in-situ deformation test, direct shear test, triaxial compressive test, large density test and particle analysis test. The test results show that the engineering characteristics of karst breccia in the dam site area is close to that of soil, and moisture content, gravel content and lateral pressure are important factors affecting deformation modulus. Water content has a weakening effect on the mechanical properties of karst breccia, and the higher the water content is, the lower the deformation modulus of the same kind of lithology is. The shear strength parameters of karst breccia determined by triaxial compression test are higher than that of the direct shear test.
Dynamic Effect of Rudder Rotary Response on Ship Manoeuvrability
Authors: Xi Chen , Yongshun Wu , Zhi Pan , Sujun Yang , Fei Wang 
Published: February 2021

Abstract
Simulation mathematical model of maneuverability such as zig-zag and turning circle test under different rudder and speed is built and the rudder rotary response effect on ship maneuverability parameters is analyzed extensively. In the paper, MMG (maneuvering model group) model is adopted to set up the 3 degrees of freedom governing equations of ships, in which the rudder rotary response is approximated by the assumption of uniform rotary speed. A sea-going vessel of 10 thousand deadweight tonnages is selected as the numerical simulation target to investigate the rudder rotary response effect on ship maneuverability parameters, such as the zig-zag and turning circle test. Some meaningful conclusions are concluded through comparative analysis, the conclusions indicate that rudder rotary response has remarkable effect on ship maneuverability, and it is a significant factor which needs to be taken into consideration for actual ships.
The development and application of BIM and virtual reality technology in the field of architectural design in the information age
Authors: Wang Xianhe 
Published: February 2021

Abstract
With the continuous development of modern information systems and computer network technology, digital building technology and virtual reality technology have emerged. In the field of architectural design, BIM technology and virtual reality technology have changed the traditional architectural design methods. They can effectively improve the efficiency of architectural design and the overall effect of architectural design. The article aims to provide a reference for the sustainable development of my country’s architectural design through the elaboration of the status quo of the development of digital building technology and virtual reality technology in the field of architectural design, the analysis of its advantages in the field of architecture, and the discussion of its application in the field of architectural design.
Elaboration of the initial requirements in the design activities
Authors: Slătineanu L , Oroian B , Condrea I , Botezatu C , Hrițuc A , Boca M A , Coteață M , Dodun O 
Published: February 2021

Abstract
In solving the design problems, the initial requirements’ clear statement significantly affects the design process’s final result. Right from when the design problems are identified, the main requirements must be defined so that the final product meets the designed equipment requirements. Designers noted that design requirements do not have equal significance, and different solutions have been proposed to consider their weight in terms of end-use properties. The weighting can be achieved by simpler and operative methods and by more detailed methods of analysis. The paper approaches the problem of using the double input matrix method for weighting the functional requirements when discussing the problem of designing equipment to investigate the behavior of a computer component when the environment temperature is different compared to the normal temperature. The functional requirements assessment could provide an overview of the financial resources that could be invested in components to adequately meet the functional requirements. A first version of the tracked equipment was designed so that the previously established functional requirements are met.
FEM analysis of stress-strain state and material consumption of RHS with longitudinal gap and weld during the tests
Authors: Kukhar V V , Sahirov Y G , Hornostai V M , Markov O E , Nahnibeda M M 
Published: February 2021

Abstract
The paper implements a method for analyzing the stress-strain state of rectangular hollow sections (RHS) by finite-element modeling (FEM) of tests for three-point bending and torsion. Design schemes, 3-D solid-state and deformable models have been developed using the automated analysis and CAD/CAE system software, made it possible to obtain equivalent stress distributions and displacements in models. A simulation of tests for RHS with a cross section of 40 mm × 50 mm, manufactured in two ways, was carried out: (a) by direct-forming of galvanized steel strips on roll-forming mill in a semi-closed section with a longitudinal gap of 0.5 mm between the edges formed on a 40 mm web (DF-RHS); (b) similar direct-forming to the closed section and next welding the edges to a longitudinal weld along the web middle of 50 mm (DFW-RHS). RHS with various wall thicknesses (t = 1.93 mm, 1.84 mm and 0.7 mm) was investigated, given the design features that depend on the manufacturing processes of structural sections. It was found DFW-RHS is stiffer by at least 50% compared to DF-RHS, which allows to savings the metal by reducing the RHS wall thickness by 62% while maintaining the same stiffness and ensuring high strength of structural section.
Analyze of shape memory wires behavior under external solicitation using finite elements analysis (FEA)
Authors: Burlacu L , Dănilă C , Birnoveanu T I , Cimpoeșu N , Bujoreanu LG 
Published: February 2021

Abstract
Nitinol shape memory alloys present many applications in the industrial areas based on exceptional memory effect properties. The behavior of a shape memory alloy (superelastic effect) underwire form (four diameters: 1, 1.5, 2 and 2.5 mm and three lengths: 75, 150 and 375 mm) at drawing was analyzed using finite element analysis (FEA). The wire shape was C letter. The experimental temperature test, in a first step, was 23 °C (room temperature) and we analyze the appliance of four solicitation forces in order to determine the specific deformations and tensions. In second simulation step we apply a higher temperature, respectivelly 80 °C, in order to analyze the behavior of the element through transformation phase from martensite to austenite. The simulation provides information on the total deformation, equivalent stress, and equivalent elastic deformation of the intelligent elements under external solicitations pointing the appearance of maximum and minimum solicitation areas.
Researches on the recovery of useful metals from spent Li-Ion batteries
Authors: Bratosin I , Ghica V G , Petrescu M I , Buzatu M , Iacob G , Necşulescu A D 
Published: February 2021

Abstract
The present and future importance of Li-Ion batteries is immeasurable; this is evidenced by the awarding of the Nobel Prize in chemistry in 2019, to the team of John Goodenough - director, M Stanley Whittingham and Akita Yashino, who developed the technology to make this type of rechargeable battery. Used at the beginning (1990-2000) in applications such as portable electronic equipments (mobile phones, laptops, electric tools, energy storage systems, etc.), these batteries are considered the most suitable battery for powering electric vehicles. Today the number of electric cars in the world has exceeded 4 million units and the future estimates are among the most optimistic. Recycling of Li-Ion batteries is mainly done in China and South Korea, countries that have a large share in their production, but things can change. Intense research for the recovery and reuse of useful metals contained in these batteries is carried out in many research laboratories. The paper presents the current state of the research undertaken for the recovery of the cathodic paste with high content of Cobalt of waste LIBs, by ultrasonography in lactic acid solution. The hydrometallurgical method uses a non-polluting organic (lactic) acid. The working technique, the results obtained and the investigations carried out on the recovered materials are presented (analysis of optical and electron microscopy, EDX, X-ray diffraction). The paper also includes data regarding the optimization of the separation process of the active cathode paste from the aluminium foil using the orthogonal central-compositional programming of the second order.
Optimization Algorithms for Energy Building Applications
Authors: Tsala S , Koronaki I P 
Published: February 2021

Abstract
The creation of the structured environment affects the environment in all three phases of the construction and the demolition of buildings. The appropriate design of buildings requires full identification of the interaction between the environment and the structured environment. Energy efficiency is a mandatory requirement and integral part of green and sustainable buildings. Energy efficient design optimization is both a design philosophy and a practical technique which has been proposed and used by architects and other professionals for several decades, especially in recent years. Bioclimatic construction has been an important tool for improving the construction of buildings in the past few decades. Energy-saving options in buildings include the use of appropriate materials, exposures and the use of alternative power generation systems. In the present work, the methods and tools used for building design optimization are displayed in an effort to explore the reasoning behind their selection, to present their abilities and performance issues, and to identify the key characteristics of their future versions. In this essay, several algorithms are provided for optimizing problems which are proposed for building construction. Depending on whether limitations are given and on the general form of the optimization problem, one could choose the optimization algorithm which suits each case.
Waste energy recovery simplify assessment
Authors: Knapčíková L , Hricová R , Pandová I , Pitel’ J 
Published: February 2021

Abstract
The paper deals with research on the energy recovery of municipal solid waste and the related impact of the recovery on the environment. Through research steps, analyses of the current production of waste, its energy recovery and the impact on the environment were gradually performed in the Prešov self-governing region in Slovakia. A simplified comparison was made between the impacts of the current landfill method and the proposed incineration method. In terms of forecasts for the development of municipal solid waste produced in the coming period, scenarios of solid municipal waste treatment possible alternatives for the future period are outlined by the help of the electronic monitoring platform.
The wastewater using in technologies of bio-oil production from microalgae: CO2 capture and storage
Authors: Chernova N I , Kiseleva S V 
Published: February 2021

Abstract
Bioenergy remains the largest renewable energy industry. At the same time, microalgae (MA) are a promising object of research among other types of biomass and the scale of microalgae using for energy purposes is increasing. Industrial cultivation of microalgae opens up great opportunities for CO2 utilization and wastewater treatment from organic and mineral pollutants, and also significantly reduces the load on fresh water supplies. To reduce the cost of biofuels, optimization of a whole number of technological stages, including the cultivation of MA, is necessary. The paper presents the results of developing methods for cultivating MA to optimize their growth and absorption of nutrients from wastewater. A culture of microalgae/cyanobacteria Arthrospira platensis rsemsu P (Bios) (collection of RSE Laboratory at Lomonosov MSU) which grew well in wastewater was experimentally selected. The results of the wet MA biomass conversion into bio-oil by hydrothermal liquefaction (HTL) technology with the associated production of biochar are presented. Biochar producing can be considered as a method for capturing and storing carbon.
The influence of the hybridization factor on vehicle energetic consumption for different e-gearbox configurations
Authors: Rențea C , Bățăuș M , Maican S , Oprean M , Frățilă G 
Published: February 2021

Abstract
To reduce the CO2 emission level for the new CAFE regulations, it is mandatory that automobile producers should choose the hybridization approach.
Relevant published literature show that for a mild hybrid passenger car, increased values of the hybridization factor (HF) have marginal influence over the fuel economy for high speed values if a fixed ratio e-gearbox is used. This paper analyzes the energetic consumption for a Through the Road Hybrid Vehicle (TTR-HEV) when using a two-gear ratio transmission for the electric axle.
To investigate the energetic performances, a complex model developed in a performant simulation environment is used. The energetic consumption is determined for five different test cycles in terms of speed and duration by analyzing the fuel consumption ratio (FCR) for different values of the HF.
In order to compare the test cycles, the FCR parameter is used, after which the correlation with vehicle speed fluctuation (VSF) is explored.
The simulation results obtained for the current application are compared with a hybrid vehicle equipped with a single gear in the rear axle. The results are also expressed in terms of CO2 emission.
The use of the genetic algorithms for optimizing public transport schedules in congested urban areas
Authors: Șerban A. 
Published: February 2021

AbstractTransit operators face with travel time variability issues related to the design of new transit lines or related to the improvement of the performances of existing lines, especially when transit vehicles without exclusive line. Nowadays, the availability of large data through automated monitoring allows more in-depth this phenomenon of variability in timetables to be pointed out with recorded data. The lack of schedule stability confuses the traveling public and thus the degree of dissatisfaction increases. This leads to a decrease of the public transportation users, especially because of those users having travel alternatives to public transportation. The reliability of the travel time and the vehicle operation according to a stable timetable are the most relevant attributes for the users fidelisation. At the same time, it is well known that the demand for public transportation in congested networks has a large variability over space and time. In this paper, we analyse the deviations from the planned (declared and publicly) schedule for a tram line in Bucharest city in different stations, in diferrent times of the day and in different days of the week, in order to build an optimisation model for needed adjustments to the planned schedule. The data are collected with the Automatic Vehicle Location (AVL) system installed on trams’ board. The number of the adjustments solutions is very large and the genetic algorithm is engaged for the optimisation model solving.
Overview of the III International Conference on Advanced Technologies in Aerospace, Mechanical and Automation Engineering – MIST: Aerospace-III-2020
Authors: Kovalev Igor V , Testoyedov Nikolay A , Voroshilova Anna A 
Published: February 2021

Abstract
The overview describes the main directions and results of the III International Conference on Advanced Technologies in Aerospace, Mechanical and Automation Engineering - MIST: Aerospace-III-2020 held in Krasnoyarsk in November 20-21, 2020. It gives the details about the participants and the proceedings.
Forming a tubular ridge by pulsed-magnetic field pressure
Authors: Kurlaev N V , Matveev K A , Tagoev F M , Ahmed Soliman M E 
Published: February 2021

Abstract
When creating samples of new technology corresponding to the current level of development of mechanical engineering, ever higher requirements are imposed on the accuracy and quality of parts and assemblies, including thin-walled tubular parts of aircraft. To ensure such accuracy, this work proposes a magnetic pulse stamping process. In particular, for the formation of a tubular ridge, the technological process of forming in addition to calibration by a magnetic pulse field is proposed. To study the stress-strain state of the workpiece and the tool, the finite element method was applied using the ANSYS program. The calculation results were summarized in the form of a nomogram to determine the required technological modes, taking into account the material properties and the pressure amplitude of the pulsed magnetic field. The data obtained as a result of numerical simulation create the basis for identifying and subsequent accounting for the technological heredity of the material.
Model of a turbulent flow of a two-phase liquid with an uneven distributed phase concentration in a horizontal pipe
Authors: Ilhamov Kh Sh , Narzullaev D Z , Ilyasov Sh T , Abdurakhmanov B A , Shadmanov K K 
Published: February 2021

Abstract
We study the turbulent stationary motion of a mixture in a horizontal cylindrical pipe, taking into account the formation of a concentration field of the second dispersed phase that is not uniform over the cross section, and estimate the transporting ability of the flow. The article has developed a model for the movement of a two-phase mixture in a horizontal cylindrical pipe, taking into account the uneven distribution of the concentration of the second phase over the flow … Also, in this model of mixture motion, the coefficient of the force of interaction between the phases is determined depending on the concentration distribution. The problem is solved by a numerical method. Investigating the numerical results of the problem, the nature of the formation of the velocity field at various values of the flow saturation with solid particles is revealed and makes it possible to assess the account of the size of these particles, taking into account the turbulence of the flow. The implementation of the developed mathematical models and recommendations will make it possible to predict the transporting ability of a two-phase flow in pressure systems, and helps to find solutions with spatial hydrotransport and irrigation and drainage systems.
Influence of tightening fitting accuracy for resource connection
Authors: Leonov O A , Shkaruba N Zh 
Published: February 2021

AbstractA dependence have obtained for determining the design tolerance of fit, as one of the characteristics of the model of parametric failure of a joint with an interference fit, the calculation is carried out taking into account the wear rate and the parameters of its dispersion at a certain resource and a given probability of failure-free operation. On the example of calculating a connection with an interference fit, it have shown that the choice of a fit without a margin of accuracy cannot ensure the operational reliability of the connection, but only guarantees the absence of failures at the initial stage of work – during the warranty period. It have proven that with the right choice of fit accuracy, it is possible to achieve a significant increase in the resource of failure-free operation.
Method of precision dimensional analysis in modelling of technological processes for shafts manufacturing
Authors: Khalimonenko A D , Pompeev K P , Timofeev D Yu 
Published: February 2021

Abstract
In this paper, we propose a method for conducting a dimensional - precision analysis of technological processes of making shafts using bench centers and consider the features of its application. A method for drawing up rotation error diagrams for processing shafts installed in the centers of lathes has developed, taking into account the principle of constancy of bases and the presence of an error in pre-centering the initial shaft workpiece.
Optimization of filtration process management in hydrometallurgy
Authors: Kustashev P A , Kazakovtsev L A , Rozhnov I P , Kirikov I N , Burmistrov E P 
Published: February 2021

Abstract
In the process of processing deactivated catalysts, there are problems that arise at each of the stages: in the process of filtration, carburizing and obtaining a concentrate of platinum (palladium) for transfer to refining. When considering these problems, we come to the conclusion that the purity of mother liquors affects the quality and time of catalyst processing, as well as the production of a concentrate with no impurities. The authors proposed to improve the quality of catalyst processing control at the filtration stage after the filter press to install a suspension slip control device and control automation for sampling and stopping the filter press. Such a change will improve the quality of the resulting concentrate during processing of the deactivated catalyst.
Investigation of MOSFET power losses in emergency mode of buck converter
Authors: Andriyanov A I , Malakhanov A A , Butarev I Yu 
Published: February 2021

Abstract
Operation modes of the compact SOT-23 package MOSFET in the high-frequency buck converter are considered. Transient analysis of a switching processes in the MOSFET based on a reliable SPICE model is obtained. Analysis were carried out in a wide variation of the supply voltage and load resistance in order to estimate energy losses in desired and emergency modes accompanied by a large amplitude of output voltage fluctuations of the converter. Converter operation in emergency modes with the increased transistor losses, which is related with an increase of the effective current value is shown. The possibility of high-frequency ripples occurrence on the transistor during the operation of the converter in the discontinuous-current mode is demonstrated. A circuit, consisting of the parasitic capacitance of the transistor and the inductance of the output filter which requires taking measures to compensate for these oscillations on practice in the discontinuous-current mode is shown. Investigated transistor demonstrates acceptable behavior in the circuit with the selected parameters, and the increase in energy losses during the transition to emergency modes is obtained. It requires special attention to design process for converters based on small-sized transistors in the SOT-23 package, since the latter have limited heat sink capabilities.
The optical sensor for detecting NO2 and O3 using a white GaN LED
Authors: Novikova Yu A , Ryzhikov M B , Tereshchenko G V 
Published: February 2021

Abstract
This article describes the scheme and principle of operation of an optical sensor for detecting nitrogen dioxide (NO2) and ozone (O3) based on the effect of optical absorption spectroscopy. A distinctive design feature of the proposed technical solution is that it is proposed to use an inexpensive powerful white led based on GaN as an optical radiation source, which has two relatively wide radiation peaks at wavelengths λ from 420 to 440 nm and λ from 525 to 650 nm. To separate the light streams and form separate measurement channels, three multilayer optical coatings were synthesized: a broadband beam-splitting coating and two narrow-band reflective coatings.