bluuebunny/crossref_metadata_2025 huggingface dataset:
Geoinformation technologies for studying the effects of water level fluctuation of Lake Baikal: the case of Angarsky Sor
Authors: Yu Zengina T , Kirillov S N , Slipenchuk M V
Published: December 2020

Lake Baikal is the world’s deepest lake and declared a UNESCO World Heritage Site. The most severe environmental problem facing the lake is the impact of water level regime fluctuation related to natural and human-caused factors. A core region under study is selected a territory of the Angarsky Sor – a shallow bay located in the Northeast of the lake. The research into a changing water content of the territory is based on imaginary provided by the Landsat-8 satellite. The study is focused on photographs taken in the high-water summer 2014 and in the law water level year 2015. The outcome of performed calculations is that an area of marshy and excessively wet regions has decreased more than 1.5 times, whereas there is a slight increase in the area of droughty waterless zones. Principal changes have been detected in the northern and north-eastern part of the Sor territory. Geoinformation technologies and remote sensing methods are considered to be efficient for the monitoring water level fluctuations, changes in the water surface area and vegetation mantle state of land ecosystems in the Sor region, what is essential for the preserving unique wetlands of the Angarsky Sor.
State of Humus in Soils under Rice Cultivation
Authors: Kh Sheudzhen A , Gutorova O A
Published: December 2020

The study investigates an anthropogenous influence on the humus content in meadow and meadow-bog soils under rice cultivation in Adygea (Gleyic Phaeozems and Calcic Chernic Gleysol). A field experiment focused on the use of mineral fertilizers N0P0K0 (control); N90P60K45; N120P80K60; N150P100K75 and N180P120K90 is carried out on rice paddies. Soil samples are taken from the plow layer before seeding and after harvesting of rice; a total humus content and fraction-group composition are studied. An increase in fulvic acids is detected in soils as a consequence of dominant reduction and oxidative degradation of humic acids. Heightened amounts of fertilizers make humus more fulvic. A labile fraction in the total humus content is determined to be 7.97-11.02 % in meadow soil and 5.38-8.33 % in meadow-bog soil. In labile humus of meadow soils fulvic acids prevail over humic acids (HA-1: FA (1a+1) = 0.71-0.89). A share of fulvuc compounds is higher in meadow-bog soils (HA-1: FA (1a+1) = 0.38-0.55). Mineral fertilizers taken in ratios of N150P100K75 and N180P120K90 raise a percentage of newly formed humus substances.
Innovation Clusters in the Arctic Zone of Russian Federation
Authors: Pankratov A A , Musaev R A , Badina S V
Published: December 2020

The article discusses the problems, directions and opportunities for the development of federal level innovation clusters in the Arctic zone of Russian Federation (AZRF), taking into account the Russian state long-term plans for Arctic territories development and implementing major investment projects. The article analyzes the current territorial structure of supported clusters in the AZRF, explores their industry and production specifics, and identifies the main distinctive features and characteristics of them. Based on the analysis of Russian Arctic regions socio-economic development indicators, the regions, municipalities and cities for the prospective cluster formations development are identified; directions, key specializations and cluster development factors are distinguished. The article justifies the relevance of innovative clusters formation in the context of task innovative, territorial, technological, information and communication, socio-economic development by AZRF.
Development of clonal micropropagation technique for Gloxinia hybrida hort. “Strawberry Ice-Cream”
Authors: Zaripova A A , Mukhametvafina A A , Urazbakhtina K A , Shigapova A I , Sh Akhmetova A , Kh Shigapov Z
Published: December 2020

The reported paper presents outcomes of clonal micropropagation of ornamental variety Gloxinia hybrida hort. “Strawberry Ice-Cream”. In the study conditions supporting in vitro implanting leaf blade fragments are developed with an outcome of 97 % viable explants. An optimal composition of the Murashige and Skoog growth medium is suggested; it contains BAP (0.5 mg/l) and IAA (0.2 mg/l) and brings about efficient adventive sprout regeneration. Implantation takes place in a growth medium; no root stimulating hormones are applied. The survival of regenerative plants is reported to be high after transplanting ex vitro.
Producing high-quality seeding material of Russian spring soft wheat varieties in Priobskaya zone of Altay forest steppes
Authors: Zharkova S , Nechaeva A , Kiyan N , Gefke I
Published: December 2020

A sufficient output of food and feed grain is one of priorities in Russian agribusiness. The reported study aims at the agrobiologic assessing spring soft wheat varieties in conditions of Priobskaya zone of Altay forest steppes. The experiments were carried out on production fields in 2018 – 2019. As an object of research 5 mid-ripening spring wheat varieties are taken. A maximum yield (2.1 t/ha) was produced when growing such varieties as Altayskaya zhnitsa and OmGAU 90. The variability of crops is reported to be low (Cv%<10). A high wheat gluten value is detected in the following varieties: Altayskaya zhnitsa (36.2%), Altayskaya stepnaya (36.9%), and OmGAU 90 (37.1%). A maximum of grain unit is given by Altayskaya zhnitsa (785 g/l). It is recommended to cultivate Altayskaya zhnitsa, OmGAU 90, Altayskaya 100 in Priobskaya zone of Altay forest steppes.
Increasing gross grain harvest in the southern forest-steppe zone of the Novosibirsk region
Authors: Dokin B D , Elkin O V , Balushkina E A , Aletdinova A A
Published: December 2020

The article analyzes the features of grain production in the Novosibirsk region of Russia. The authors analyzed the development of innovative technologies in farms. Unfortunately, extensive technology is still the most common. In the Novosibirsk region, 60% of agricultural enterprises use extensive technology and create 49% of the gross grain harvest with an average yield of 14.3 hundredweight/ha, 20% of farms create 26% of the gross grain harvest with a yield of 23.3 hundredweight/ha, 11% of farms create 21% of the gross grain harvest with a yield of 33.4 hundredweight/ha. The authors chose the Novomayskoye farm in the southern forest-steppe zone of the Novosibirsk region as a model. The simulation results were tested in practice, they showed that the transition to intensive technology with direct seeding (No-till) required an increase of 1.5 times the technical support and costs for mineral fertilizers and plant protection products, i.e. from 6 thousand rubles/ha of wheat crops to 9 thousand rubles/ha (in 2020, 1 USD≈65 Rub), but this allowed to reduce fuel consumption by 30 - 35% and the need for machine operators by 1.7 - 2 times.
Intensification of secondary dampening of grain before milling
Authors: Protasov N S , Fedorenko I Y , Buzoverov S Y , Sadov V V
Published: December 2020

This article describes the problems encountered by grain processing industries. In this regard, we are looking for methods of intensive grain dampening, allowing to reduce the technological cycle of flour production by reducing the time of softening. The article also considers the process of secondary dampening of grain before milling by using pulsating vacuuming and subsequent pulsing pressure. An experimental unit for grain dampening before milling is presented and the basics of its operation are described. In addition, the paper provides the results of the experimental study of wheat grain dampening using pulsating vacuum and subsequent pulsating pressure, and provides control results of the experimental study of wheat grain dampening without vacuum and pressure. The results of the experimental study were analysed; according to said analysis it is evident the increase in moisture content of wheat grain in case of dampening with the use of pulsating vacuum and subsequent pulsating pressure is more intense than in case of dampening without the use of vacuum and pressure, which leads to a two-fold reduction of the softening time. The dependence between the dampening increment ΔW and the grain processing time t in the experimental dampening unit was determined. Having analysed this work, were made our conclusions that are presented in the article as well.
Seed drill used on complex configuration fields
Authors: Plyaka V I , Sergeeva N A , Panov A I , Yakovleva N A
Published: December 2020

The seed drill moves along the field in a shuttle manner. Non-productive time spent on the seed drill turn at the end of each run increases as the field area decreases. Consequently, the waste of time reaches the greatest value on small-scale fields and complex configuration areas, naturally encircled by forests, shrubs, ravines and swamps. This leads to a marked decrease in the seed drill performance and increased specific fuel consumption. In addition, the use of seed drills in complex areas has revealed a number of limitations associated with agrotechnical indicators. This problem was solved by developing a seed drill capable of uniform sowing, both in straight-line and curvilinear motion. Curvilinear sowing implies that different amount of grain should get into coulters moving with different radii. A fluted roller seed drill has two groups of sowing units, kinematically connected with the left and right support-driving wheels. The sowing units of different groups can be coupled. Tests of the seed drill with a coupled sowing unit showed that its performance when working on complex configuration fields in case of circular motion is 28… 79% higher and specific fuel consumption is 25… 41% less than that of a conventional shuttling seed drill.
Study of the operation of a combine harvester cleaning system with a sieve screw separator in the conditions of operation on slopes
Authors: Sorochenko S F , Ugarov V A
Published: December 2020

The article presents the results of studies of a cleaning system with a sieve screw separator in operation conditions of a combine harvester on slopes. The grain heap in the proposed cleaning system is moved by screws, which ensures uniform feeding of the grain heap to the upper sieve with longitudinal tilts of the combine. Autonomous operation of the screws reduces the uneven distribution of grain heaps across the width at the beginning of the upper sieve of the cleaning system. Preliminary separation of grain reduces the grain flow to the upper sieve by more than 60%. Laboratory studies have shown a decrease in grain loss with a transverse tilt of the combine of 8 degrees from 1.17% in the compared treatment system to 0.75% in the treatment system with a sieve screw separator. An additional reduction in grain losses was achieved by installing longitudinal partitions with a height of 0.13 m on the upper sieve, preventing the grain heap from shifting sideways on the upper sieve. The theoretical coefficient of variation in the grain heap layer thickness at the end of the upper sieve is 0.18. Grain losses in the proposed cleaning system, calculated by the mathematical model of separation, amounted to 0.14%, which is 8 times lower than the compared cleaning system.
Pneumatic boom applicator for dispersion of mineral fertilizers
Authors: Byshov Nikolay , Makarov Valentin , Zhravleva Olga , Shemyakin Alexander , Starovoitova Oksana , Manokhina Aleksandra
Published: December 2020

Almost 90% of machines are used with throw-type seeding devices. Serious disadvantages of such machines include uneven application of 25% or more, depending on air humidity and wind force and can reach about 50%. The best seed-fertilizer seeders have the best performance of about 10% irregularity of application, but they have a small width of application and productivity, and in practice they are not used to fertilize the soil when preparing for sowing crops. The solution to the problem of increasing productivity and improving the uniformity of fertilizer application can be found by creating pneumatic boom applicators with a greater width than that of grain-seeders.It was found that the test machines in the field had 8% non-uniformity of the introduction of ammonium nitrate that was lower than in a case of machines equipped with throwing working bodies and approved by agricultural requirements for them. The obtained non-uniformity of the fertilizer application allows to evaluate its indicators even at the design stage of the machines, depending on the quality of dosing and the distance between the sowing ejectors.
Stress-strain modelling state and fatigue of the working body of the tillage unit for weed removal
Authors: Shindelov A V , Ivanov N M , Nemtsev A E , Vakhrushev B B , Nikolaev A D
Published: December 2020

It is possible to increase the efficiency of crop cultivation technology through the using of multifunctional equipment for soil cultivation. The analysis of tillage equipment showed that the development of a multi-functional tillage unit capable of performing the main tillage with weed removal and a set of operations for pre-sowing tillage is relevant. To quickly adapt the soil cultivating unit to changing operating conditions, the method has been developed for regulating the angle of attack of the combing machine, the width of the capture unit and the angle of entry of the working body into the substrate [1]. A method for calculating the fatigue life of the working body of a tillage unit is proposed.
The project solution of the refrigeration machine scheme with the heat utilization of condensation
Authors: Neverov E N , Korotkiy I A , Mokrushin M Y , Prib I A , Goleshov D I
Published: December 2020

Refrigeration machines are widely used in various industries to produce artificial cold. In the process of maintaining low temperatures, the refrigeration machine generates a lot of heat to compress a refrigerant, which is not used in the future, and during the condensation it is released into the environment in the form of water vapor. This negatively affects to the environment because of increasing the concentration of greenhouse gases in the atmosphere. And the use of chlorine-containing refrigerants causes the destruction of the ozone layer. To reduce environmental damage, it is necessary to increase the energy efficiency of refrigeration machines and develop schemes that allow the use of low-grade heat, which is released during operation. In the work, a scheme of a refrigeration machine was developed, which allows utilizing the heat of condensation, using it for various consumers of thermal energy, therefore allowing to reduce emissions of harmful substances into the Earth’s atmosphere and increase technological capabilities of cooling.
Using the organic Rankine cycle for heat supply of greenhouses at agricultural enterprises
Authors: Osintsev K V
Published: December 2020

The greenhouses are used at agricultural enterprises producing crop products. It is proposed to utilize the heat of the ground in order to increase the high-quality energy supply of these facilities. Organic Rankine cycle is needed to get heat in the form of hot water, as well as electricity. Hot water can heat air in heaters and maintain the required air temperature in the greenhouses themselves. Electricity production is possible due to its generation by a micro-turbine or an expander. The most promising area is the conversion of the kinetic energy of freon into mechanical work in Tesla’s radial turbines. The article proposes a variant of the heat supply scheme of the greenhouse. The most effective technological solutions of putting into practice the organic Rankine cycle are shown.
Using absorption principles of water-ammonia mixture for energy supply of agricultural enterprises
Authors: Osintsev K V
Published: December 2020

The most promising developments in the field of energy supply for industrial enterprises are research in the field of alternative energy sources. As experience in the construction of the first geothermal power plants operating along the Kalina cycle shows, the efficiency of heat use increases sharply due to the utilization of the heat of low-potential energy sources. As such, energy sources use ground, in particular, geothermal water. In regions where there are enough geothermal sources, power plants based on the Kalina cycle can be used. The generated heat and electricity can be used for agro-industrial complexes. This is possible, as theoretical studies show, for enterprises in the field of crop production, animal husbandry and processing of agricultural products. In addition, the article describes the principles of using absorption refrigeration machines in agriculture.
The Reduction Of Activity Of Antialimentary Compounds Of Vegetable Raw Materials Under Exposure To Electric Discharges
Authors: Kazub V T , Orobinskaya V N , Galdin E V , Yemelyanov S A
Published: December 2020

The article deals with the issues related to the harmful effects on the human body of anti-nutritional components (anti-nutritional factors of natural origin) that can block active enzymes that break down protein compounds. A comparative analysis of anti-nartative components of protein-containing plant origin under the influence of thermal nature and parameters of electric-discharge treatment has been carried out
The Use Of Phyto-Enrichment Agents In The Production Of Functional Bakery Products
Authors: Orobinskaya V N , Kholodova E N , Galdin E V , Yemelyanov S A
Published: December 2020

An anthropogenic pollution, a sedentary lifestyle, a sharp jump in the growth of cardiovascular diseases and oncological diseases led to the need to develop functional products of a new generation that reduce the effects of the harmful factors listed above.
Research of the wear mechanism the rubber lining mining trucks
Authors: Kopchenkov V G , Babich A G
Published: December 2020

The rubber lining used to protect the bodies of mining trucks is characterized by impact at an angle to the surface of the lining.

Described experimental installation, allowing to model the impact of single solid parti-cles at an angle to the surface of the rubber. It is established that the basis of the mecha-nism of the fracture of rubbers under oblique impact is cracking. The development direc-tion of cracks is approximately equal to the angle of attack, i. e. the direction of the force of impact. The destruction is cyclical in nature and follows the scheme: the tear of the surface — rip crack — turn cracks and separation of the fragment. Factors determining the length and depth of the development of the initial crack set.
Increasing the efficiency of agricultural transport and technological machines in the operation
Authors: Kokieva G E , Shaposhnikov Y A
Published: December 2020

Production of commercial agricultural products is impossible without transport and technological machines and their technical-readiness, through repair and maintenance. The relevance of this direction is due to the agricultural producers’ lack of necessary material and technical base, required production structures, taking into account multistructurality, and various forms of ownership. The use of transport and technological complexes and maintenance tool for their setting and adjustment allows to reduce labor costs and improve the quality of mechanized works. With the increase of commercial agricultural production technical capacity, some issues have emerged: increasing the costs of machines, increasing expenses of production per unit, and also the complicated operation system of mechanisms. As a result, the indicators of their use are not improved. Reformation of management methodsin agriculture is aimed to solve the issues of technical and economicprovision of agricultural products producers with the necessary technical resources. To solve this problem, differential standards of resource requirements should become essential, taking into account the production volume. It is necessary to increase the technical-readiness of transport and technological machines and thus the cost-effectiveness of their use.
Modern approaches of vehicle suspension durability evaluation at early stages of development
Authors: Kulagin V A , Bokarev A I
Published: December 2020

Ensuring demanded service life of a vehicle is a relevant engineering problem. Currently, resolving this problem is heavily complicated. Modern tendencies of automotive industry assume shortened development cycle for new vehicles and sustaining wide lineup of cars for manufacturers. Performing long-term durability testing of vehicle subsystems is becoming limited. Meanwhile, methods of laboratory testing, which provide higher acceleration degree of damage accumulation in comparison with testing on proving ground, are progressing. Virtual simulation methods, which allow analyzing and optimizing a new design at early development stages, are becoming widespread as well. Modern durability analysis methods, based on laboratory testing and virtual analysis, and load cycle generation methods, used for testing and simulations, are considered. Some points are noted, such as an extensive use of described methods of durability research among foreign car manufacturers, and the relevance of developing this kind of durability evaluation methodology for the Russian automotive industry.
Vibrations analysis of bogie’s axle from an electric locomotive class 43
Authors: Alexandrov M , Goanţă V , Paleu V , Apostol D , Atanasiu M
Published: December 2020

Reliability and maintenance play an important role in the field of rail vehicle systems. In order to be reliable, this type of transport needs continuous monitoring and regular maintenance. Regarding requested repair and maintenance interventions in relation to the probability of failure for each component, assembly or subassembly, additional information could be taken by data acquisition from sensors fitted to the locomotive bogies. The influence of the rail pattern configuration and the asymmetry of the positioning of both the traction motors and the gearbox on the amplitude and frequency of the introduced vibrations is considered. Fast and robust online signal processing algorithms are essential for designing a smart device. In this way, maintenance models can be created based on the state of the systems and integrated platforms can be produced in order to improve the diagnosis and expertise of a maintenance program. The paper presents the method of determining the vibrations induced by various causes at one of the axles of the electric locomotive class 43, of 3400 kW (4620 hp), focusing on rolling bearings fault frequencies. Further research will aim to detect the other possible sources of vibrations transmitted at the bogie’s axle.
Fractal rigidity of the wheel-rail contact
Authors: Babici L M , Tudor A , Romeu Garbi J , Stoica M
Published: December 2020

One of the essential parameters of the roughness with effects on the vibration of the wheel and the rail is the contact stiffness. This rigidity considers the geometry and material of the wheel and rail, which are considered elastic. Also, the micro-geometry of the roughness and the load on the wheel, with elastic, elastoplastic and plastic deformations, depending on the deterministic or random character of the roughness were considered. The dependence of the stiffness on the deformation state of the roughness may explain the different amplitude of the vertical vibrations at the same force on the wheel and the same height of the roughness, but one roughness with different fractal parameters. For the analysis of the dynamic forces in contact, the continuous and underived analytical function that modelled the roughness measured experimentally on the rail was applied.
Investigating the friction reduction capability of dimpled surface using CNSL as lubricant
Authors: Bhaumik S , Paleu V , Chowdhury D , Pranav MM , Paleu Cîrlan C
Published: December 2020

This work investigates the friction reduction capability of dimple – textured steel surface created using a vertical milling machine. A suitable geometry for creation of dimples was chosen and cashew nut shell liquid (CNSL) was used as lubricant. A L9 orthogonal array was created using Taguchi design of experiment where load, speed of disc and duration of the test were chosen as the parameters. A pin – on – disc tribometer is used to find the coefficient of friction (COF) between an EN 24 steel pin and the dimple – textured steel disc made of low carbon steel. ASTM G99 standard was used for the test and the lubricant was supplied intermittently. Optimization was carried out using Taguchi method, where the optimized condition of the input parameters influenced a substantial change of 32.38% in COF as compared to the non – textured disc surface. The lubricant retention capacity of the dimple was the primary cause for the decrease in COF.
Influence of tightening screws process in high-pressure injection pump
Authors: Bistriceanu D P , Pal S G , Alaci S , Bujoreanu C
Published: December 2020

The high-pressure pump is a component of the automotive common-rail system and has as main assemblies: housing, driveshaft, gaskets and front plate. Literature presents analyses of the threaded fastening assemblies, especially for those with the critical joints with screws, those involving torque and angle. The assembly process that we have studied performs the sealing of the components with the gasket through the screws, thus preventing the fuel from leaking from the pump. Our paper presents an analysis of the influence of the tightening process with screws of the housing, gasket and front plate. The experiment was conducted using the Zeiss measuring system and the screwdriver Janome. The tests analysis demonstrates that screwing process can influence the distortion.
About four balls scuffing test parameters
Authors: Hangan’ C , Românu I C , Muscă I
Published: December 2020

The paper aims to contribute to the understanding of scuffing occurrence. The evolution of surface topography during four balls tests using two types of grease was investigated. For testing, a four balls experimental setup was used. The test rig allows loading the contact between balls while maintaining relative motion between surfaces. Constant velocity is maintained for 10 seconds as per the EN ISO 20623:2003 procedure. The wear scar produced during testing was investigated by means of an optical 3D profilometer and the roughness parameters were analysed. Experimental results reveal that the values of arithmetical mean height Sa and root mean square height Sq, have a significant growth and they are correlated with the occurrence of the scuffing phenomenon.
Influence of the stiffness and the speed on the stick-slip process
Authors: Oprişan C M , Chiriac B , Cârlescu V , Olaru D N
Published: December 2020

In this paper the authors experimentally investigated the influence of the linear speed and the stiffness of a single degree-of-freedom mass-spring system on the evolution of the stick-slip process. Using the UMT-2 Tribometer a steel mass was sliding on glass surface with a linear speed varied between 0.02 mm/s and 1 mm/s and spring stiffness varied between 40 N/m and 442 N/m. The experimental results evidenced that increasing both the linear speed and the spring stiffness can reduce the stick-slip process. Thus, the authors proposed an original friction model to simulate the stick-slip process by considering the dependence of the dynamic coefficient of friction with the sliding speed in the “slip” phase. The theoretical model is based on dynamic equilibrium of all the forces acting on the mass in transient phases. The proposed theoretical model was validated with experiments by simulating the stick-slip process for given linear speed and spring stiffness.
Calculation elements for establishing the design of a rotating machine that transports fluids
Authors: Stoican (Prisecaru) M M , Băran N , Costache A
Published: December 2020

The paper presents the operating principle and the constructive solution of a rotating machine with two profiled rotors.

The calculation relations between the rotor radius and the height of the rotating piston are established, fundamental relations for the design of the rotating machine. The calculation results on the basis of a computation program are presented, results which specify by the coordinates (xi, yi) the contour of the rotor profile.

At the end of the paper, the formula for calculating the flow rate transported by the machine and its driving power is analysed.
Theoretical investigation of optical phenomenon from nanometric antireflex layers
Authors: Pascu A T , Pascu M A , Besnea D
Published: December 2020

Within the paper were studied the physical phenomenon which characterize the passing of light through a dielectric environment, a case which can be applied to eyeglass lenses with a nanometric antireflex layer. Were determined the optical characteristics required or such nanometric layers. Was studied practically the increase of light transmission, respectively the reduction of reflection for this new manufacturing technology for eyeglass lenses and the nanometric antireflex layers. The study was completed with photometric measurements and measurements for the resistance of the antireflex coatings compared for several manufacturing technologies.
Researches regarding the static and dynamic behaviour of composites with natural reinforcements
Authors: Rădoi A I , Miriţoiu C M , Bogdan M , Stănescu M M , Bolcu D
Published: December 2020

In this paper, some composite materials were built in this way: the reinforcement is made with natural fibers (there were used two types of natural fibers in this way: hemp and cotton) and the matrix is made from epoxy resin. The Resoltech 1050 epoxy resin is used, with its Resoltech 1050 hardener. The casting was made at room temperature and the matrix was applied using the brush. The static experimental conditions are characterized by tensile loading of the build specimens and the determination of statically Young modulus. There was used an Instron Universal testing machine and the force-extension curves were obtained. The dynamic parameters were determined from the bars free vibrations. The next experimental montage was used: the bars were clamped at one end and were left free at the other end. At the free end, a Bruel&Kjaer accelerometer with 0.04 pC/ms−2 sensitivity was placed in order to record the beams dynamic response. A force was applied at the free end to bend the beams and after bending, the force was cancelled and the beams were left to freely vibrate. The accelerometer was connected to a signal conditioner Nexus and the signal conditioner was connected to a data acquisition system SPIDER 8 made by Hottinger Baldwin Messtec. The acquisition system was connected to a notebook and the experimental parameters were obtained through CATMAN EASY software. From the free vibrations recording, the next mechanical parameters were determined: the eigenfrequency of the first eigenmode, the damping factors per unit mass and per unit length, the loss factor and the dynamic Young modulus.
Fatigue cracks in aluminum alloys structures detection using electromagnetic sensors array
Authors: Steigmann R , Iftimie N , Dobrescu G S , Danila A , Barsanescu P D , Stanciu M D , Savin A
Published: December 2020

The paper presents the architecture of a new type of electromagnetic sensor in 2D structure designed and made in order to estimate the location of a discontinuity below the surface of a conductive material. The use of 2D emission reception architecture in configuration of 5x5 identical reception sensors excited by a surrounding emission coil is proposed. The analysis follows the way in which one or more linear fatigue cracks that intersect can affect the eddy current answers and the electromotive force induced in the reception coils. The study of the dependence of the field distribution on the number and position of the reception coils against the discontinuity was carried out using FDTD. Spatial resolution has been improved using a known super resolution algorithm. The 2D structure was tested for the detection of subsurface discontinuities induced in Al2024 samples subjected to cyclic loading.
Trends and perspectives in proportional pneumatics
Authors: Avram M , Sgârciu A I , Bucşan C
Published: December 2020

Trends and perspective directions in the field of pneumatic equipment and systems are first identified in the paper. Special attention is given to identifying the equipment and systems that can be adapted to the requirements imposed by a new industrial revolution - Industry 4.0. Pneumatics will continue to be an important domain and the paper presents arguments for that. The current stage of proportional pneumatics is presented and a comparison between analog and digital proportional pneumatics is made. In the final part of the paper an experimental model of a distributor controlled with modulated pulses is presented. The distributor is integrated in a system that controls the pressure in a reference volume.
Constructive and functional particularities of 3D printers with applications in the food industry
Authors: Besnea D , Avram M , Cananau S , Moraru E , Spanu A , Constantin V , Panait I C
Published: December 2020

The paper presents the construction and operation of a 3D printer that uses the principle of food raw material extrusion with possible applications in the food industry. The emergence of these additive technologies has led to the obtaining of complex customized three-dimensional products starting from a 3D CAD model. Among the advantages of this technology with applications in the food industry can be listed: obtaining personalized food products with innovative forms especially in the confectionery and pastry area; obtaining food products that have in the component known raw materials (allergies, intolerance), forms, colour, strictly controlled nutritional value; the possibility of integrating this technology in long-term space missions by creating foods of different shapes and compositions. Also, older people can be helped to deal with the problems of chewing and swallowing. The disadvantages of 3D printing technology with applications in the food industry are related to food safety, because strict hygiene conditions and working temperature control must be ensured. Also, the future development of this technology can lead to the saving of large quantities of food raw materials.
Improving the Electric Response of a Cantilever Piezoelectric Energy Harvester by Constraining Tip Curvature
Authors: Borzea C I , Comeagă C D , Uddin M N , Hriţcu R D , Ringheanu V L
Published: December 2020

The paper studies the influence of tip curvature on the electrical response of a piezoelectric energy harvester, on a direction other than the charge generation one. Finite element analyses were conducted for the given piezoelectric transducer, which show an increase in the voltage output if blocking the tip curvature on yOz plane between two bars, leaving free only the deflection on xOz plane. The comparison was made between cantilever tip constrained with bars and cantilever with an equivalent proof mass respectively. The simulations in COMSOL Multiphysics are furthermore validated by experimental laboratory tests, confirming the increase of the electric output potential with ~8%. This occurs due to inducing higher stress into the structure by blocking its tip curvature. The frequency response, defined between base excitation and the output voltage, was determined using an impedance analyser. The bars also act as a proof mass, thus decreasing the resonant frequency optimally down to the vibration frequencies of an oil-free compressor’s downstream pipe on which the transducer will be mounted in order to harness the inherent vibrations and subsequently power wireless sensors.
Development of an inertial propulsion drive by using motion simulation
Authors: Geröcs A , Korka Z I , Nedelcu D , Gillich G R
Published: December 2020

Beginning with the last century, visionaries and researches from all over the world have invested o lot of energy and time in the development of various drives for generating propulsion force. The present paper is dedicated to the kinematic and dynamic investigation of an inertial propulsion drive using the facilities of the Motion module from SolidWorks (SW) software. Following elements were considered: positional analysis, velocities and acceleration simulation, force generation and power consumption. As the obtained simulation results showed a good closeness to the analytical outcomes, the authors are optimistic regarding the possibilities to develop and improve the system.
Development of cyber physical system based manufacturing system design for process optimization
Authors: Jamwal Anbesh , Agrawal Rajeev , Manupati Vijaya Kumar , Sharma Monica , Varela Leonilde , Machado José
Published: December 2020

Cyber physical systems (CPS) are known as one of the significant advancement in computer science and IT. Cyber physical manufacturing system is the emerging research area in the field of computer science as well as manufacturing science and technology which is promoting the 4th industrial revolution which is known as Industrie 4.0. CPS generally focuses on the integration of physical world with cyberspace. It is the integration of communication, computation, control and physical elements. At present time, CPS is the point of interest for academia, government and industries. However, a systematic literature review of cyber physical system for manufacturing system is not available. This paper aims to present the findings on cyber physical systems on manufacturing systems and development of cyber physical system for intelligent manufacturing. The CPS is explained with the concept of CPS and five level architecture system for manufacturing systems. Further, key enabling technologies for cyber physical manufacturing systems is also discussed. In this paper both WoS and Scopus databases (2000-2020) is taken in consideration for literature review. Top journals, top cited papers, top authors and top research categories have been found out.
Laser-assisted additive technologies for the execution of dental restorative prostheses
Authors: Moraru E , Dontu O , Rizescu C , Spanu A , Ciobanu R , Draghici C
Published: December 2020

In the paper the authors present a technology with a great development perspective applied in restorative dental prosthetics based on the action of the laser. Also, there is presented an additive manufacturing method for obtaining dental prototypes from special materials, which can have multiple applications in the dental field. By this, dentists can replace the traditional outdated methods of prosthesis. A 3D printer for dentistry is a real opportunity to automate the most important stage in the work of dental laboratories, as well as move to a new level of quality. High productivity, waste-free production, possibility of realization of complex geometries - this is only a small part of the advantages of these technologies for metal and polymeric printing. The researches in this article even show that the prostheses made by selective laser melting have some better mechanical properties than the conventional casted prostheses from the same material.
Displacement and velocity estimation of the earthquake response signals measured with accelerometers
Authors: Nedelcu D , Malin T C , Gillich G R , Barbinta C I , Iancu V
Published: December 2020

We propose in this paper a method to calculate the antiderivative of signals that have the integral close to null, as the signals measured on structures during earthquakes are. The method implies performing a series of numerical integration considering the initial value being zero. Afterward, the average value for the primitive function is calculated and considered as initial value: this solves the initial value problem with acceptable precision. Because of the minor errors, the second antiderivative that is the displacement in our case will gain a continuously slight increase. We overcome this problem by finding the trendline and extracting it from the signal representing the second antiderivative. In this way, we obtain accurate instantaneous values for the displacement as well. The algorithm, nominated as PySEMO, is implemented in the Python programming language and used to demonstrate the accuracy of the method. At the end of the paper, we make recommendations for the acquisition strategy to guarantee to find precise velocities and displacements. The algorithm can be used for other signals alternating around zero, e.g. those measured on rotating machines, as well.
Design, simulation and experimentation of an electro-dynamic system for semi-active control of vibrations
Authors: Popescu N , Comeagă C D , Avram M
Published: December 2020

Previous work regarding the vibration transmissibility control, using electrodynamic actuators, based on semi-active solutions, proved the efficiency of this strategy. The studied system is a simple, one degree of freedom system. The system integrates mechanical components for passive isolation and an electrodynamic actuator for active and semi-active control of vibrations. The most efficient solution is to design an accurate model and simulate strategies on it. Two strategies are involved: feed-forward control with an accelerometer placed on the mobile mass for acceleration detection and the second one is based on movement detection using the self-induced current due to the actuator's coil movement in a magnetic field. A detailed simulation model, using a software designed for electronic circuit simulation and experimental testing are performed in both cases. The model should be improved for considering the complex impedance of the actuator (mechanically but also electrically), this being the subject of future works.
The quality of metal products bent on CNC machines
Authors: Puşcaş (Popescu) N , Tempea I
Published: December 2020

The world market must provide products, that adapt to customer needs, which implies large investments and long-term employments. The way of thinking of the buyers is anticipated by the producers. The paper presents studies and researches in the field of bending of metal parts with thickness of 2 mm. The studies and researches have offered answers to the many problems that companies face. The quality of the products is the main attribute. In the first stage of the research, the unfolding of the flat parts was determined. A bending coefficient Kî was introduced in the calculation of the plane parts. The quality and precision of the parts was influenced by different variables: the temperature variation during the processes of punching and bending, vibrations of machines, tool usage, tolerance between the surface of the bending tools, their usage and the roughness of the metal sheet, the type of the material, the chemical composition, the degree of complexity and the number of bends, the movement between the piece and punching or bending tools and other variables. The calculation of the unfolded (flat parts) was a priority, as it must include the deformations caused by the bending operations. Bending coefficients Kî must compensate for deviations from the final dimensions of the metal products, because of the many variables that can adversely affect their execution. The quality and precision of the bent pieces, with a thickness of 2 mm, is the objective of this paper. The bending coefficient was obtained through experimental tests and measurements.
Designing and testing a stand used to simulate the dummy head impact with different surfaces using CAD software
Authors: Radu A I , Trusca D D , Toganel G R , Benea B C
Published: December 2020

The aim of the paper was to design, assemble and test a stand used to analyse various crash scenarios for a crash test dummy head. This stand can be used to test the head impact with different surfaces, with or without a helmet, on soft or hard surfaces at different impact angles. The idea was to design the stand in the CAD software SolidWorks because this particular software has the feature of dynamic simulation of assemblies known as Motion Analysis. The results show that designing the stand was a success and the simulations show a good behaviour of the assembly with direct results generated in term of acceleration and force values obtained from the drop test of the head on a surface. Also, the surface can be adjusted for different impact angles and with different contact surfaces properties to extend the usability of the assembly.
Arduino based mobile robot controlled by voluntary eye-blinks using LabVIEW GUI & NeuroSky Mindwave Mobile Headset
Authors: Ruşanu O A , Cristea L , Luculescu M C
Published: December 2020

This paper proposes an experimental system of a brain-computer interface aimed to use the voluntary eye-blinks detected across the EEG signal acquired from a NeuroSky headset to control the movement directions of a mobile robot. Bluetooth protocol was used to achieve the communication between a LabVIEW application and a program uploaded in an Arduino Mega board which controls the movement direction of a mobile robot. Three parallel algorithms were implemented using LabVIEW, one for the voluntary eye-blinks counting, one for switching across buttons and one for selection of a certain command. Transition across commands (stop, go forward, go backward, turn left, turn right) is executed by one voluntary eye-blink, while two intentional eye-blinks determine the selection of a specific command.
Intelligent speed control system for electric vehicle
Authors: Turcian D , Dolga V
Published: December 2020

An important topic nowadays is to have cars and roads that provide comfort and safety. Mechatronics systems are used to have this approach. The brake system is now base on an electronic stability system, the steering system is partly or fully automated and the speed is control by the cruise control system. The new target for the automotive industry is to create a car able to decide by itself on all actions related to safety and comfort – a fully automated vehicle. One of the most important innovations for autonomous driving is drive by the idea of connected cars: car2car and car2infrastructure. In the present paper, it is analysed a cruise control system based on communication technology. A simple prototype is build up using Arduino and modules for communication. To calibrate and parametrize the system, we use a Simulink model.
The conjugate profile of the circular teeth of a spur gear. Part I: Problem statement
Authors: Ciornei F C , Alaci S , Doroftei I
Published: December 2020

The paper presents the manner of finding the conjugate profile of a circular tooth of a spur gear. A synthesis of the method of enveloping applied to the cam mechanisms is presented in order to relate it the profile of the spur gears. The main argument of employing cam mechanisms is the possibility of obtaining any follower law of motion using a minimum number of parts- the cam and the follower. In the case of the mechanisms with flat face follower, the cam is obtained as an envelope of successive positions of the follower. The gear mechanisms are a particular case of cam mechanisms. The major requirement imposed to this mechanism is to transmit the rotational motion between two shafts with a constant transmission ratio. From here it results that the profile a geared wheel can be completely identified when there are known the distance between the axes, the transmission ratio and the profile of one of the wheels. The most used curve as tooth flank is the involute of a circle, due to the fact that this curve has as conjugate curve an involute, too. Although the involute profiles are common in most of the technical appliances, there are cases when they cannot satisfy the functional constraints of certain devices. As example, in the mechanical watches technology, large transmission ratios are needed and the gears with small number of teeth are used as routine. But this necessity is better fulfilled by cycloidal profiles than the involute ones. The circular profiles for the spur gear are the oldest gears due to the simple profile. The exact conjugate profile of a circular tooth obtained by enveloping by means of dedicated software is presented.