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Statistical regression models have rarely been used for engine exhaust emission parameters. This paper presents a three-step statistical analysis algorithm, which shows increased prediction accuracy when using vibration and sound pressure data as a covariate variable in the exhaust emission prediction model. The first step evaluates the best time domain statistic and the point of collection of engine data. The univariate linear regression model revealed that non-negative time domain statistics are the best predictors. Also, only one statistic evaluated in this study was a statistically significant predictor for all 11 exhaust parameters. The ecological and energy parameters of the engine were analyzed by statistical analysis. The symmetry of the methods was applied in the analysis both in terms of fuel type and in terms of adjustable engine parameters. A three-step statistical analysis algorithm with symmetric statistical regression analysis was used. Fixed engine parameters were evaluated in the second algorithm step. ANOVA revealed that engine power was a strong predictor for fuel mass flow, CO, CO2, NOx, THC, COSick, O2, air mass flow, texhaust, whereas type of fuel was only a predictor of tair and tfuel. Injection timing did not allow predicting any exhaust parameters. In the third step, the best fixed engine parameter and the best time domain statistic was used as a model covariate in ANCOVA model. ANCOVA model showed increased prediction accuracy in all 11 exhausted emission parameters. Moreover, vibration covariate was found to increase model accuracy under higher engine power (12 kW and 20 kW) and using several types of fuels (HVO30, HVO50, SME30, and SME50). Vibration characteristics of diesel engines running on alternative fuels show reliable relationships with engine performance characteristics, including amounts and characteristics of exhaust emissions. Thus, the results received can be used to develop a reliable and inexpensive method to evaluate the impact of various alternative fuel blends on important parameters of diesel engines.
Tadas Žvirblis; Darius Vainorius; Jonas Matijošius; Kristina Kilikevičienė; Alfredas Rimkus; Ákos Bereczky; Kristóf Lukács; Artūras Kilikevičius. Engine Vibration Data Increases Prognosis Accuracy on Emission Loads: A Novel Statistical Regressions Algorithm Approach for Vibration Analysis in Time Domain. Symmetry 2021, 13, 1234 .
AMA StyleTadas Žvirblis, Darius Vainorius, Jonas Matijošius, Kristina Kilikevičienė, Alfredas Rimkus, Ákos Bereczky, Kristóf Lukács, Artūras Kilikevičius. Engine Vibration Data Increases Prognosis Accuracy on Emission Loads: A Novel Statistical Regressions Algorithm Approach for Vibration Analysis in Time Domain. Symmetry. 2021; 13 (7):1234.
Chicago/Turabian StyleTadas Žvirblis; Darius Vainorius; Jonas Matijošius; Kristina Kilikevičienė; Alfredas Rimkus; Ákos Bereczky; Kristóf Lukács; Artūras Kilikevičius. 2021. "Engine Vibration Data Increases Prognosis Accuracy on Emission Loads: A Novel Statistical Regressions Algorithm Approach for Vibration Analysis in Time Domain." Symmetry 13, no. 7: 1234.
The natural processes of interactions between aerosol particles in the ambient air through which they agglomerate is a vast area of chamber research and are inherent to many industries and are often inter-connected with transport engineering. Further improvement of symmetric methods for aerosol particle number and mass concentration reduction made it possible to create various synergic techniques. The study used a 1.9 TDI diesel internal combustion engine, which was supplied with diesel (D100) and second-generation biofuels (NExBTL100) with the EGR exhaust system on and off. Measurements were performed using a Bruel and Kjær “Type 9727” system for measurement of vibrations, a scanning mobility particle sizer (SMPS) and an original agglomeration chamber. The three modes of particle size distributions were observed in the size range from 10 to 470 nm for both D100 and NExBTL100 fuels with and without the use of the EGR system. The application of 21.3 kHz frequency sound with SPL 144.1 dB changed the NExBTL100 generated aerosol particle number concentration but did not sufficiently affect the concentration of D100 emitted particles. The greatest agglomeration effect (21.7 ± 10.0%) was observed in the range of extremely small NExBTL100 derived particles (10–70 nm) when used in combination with an EGR system.
Inga Garbarienė; Vadimas Dudoitis; Vidmantas Ulevičius; Kristina Plauškaitė-Šukienė; Artūras Kilikevičius; Jonas Matijošius; Alfredas Rimkus; Kristina Kilikevičienė; Darius Vainorius; Algirdas Maknickas; Sergejus Borodinas; Steigvilė Byčenkienė. Application of Acoustic Agglomeration Technology to Improve the Removal of Submicron Particles from Vehicle Exhaust. Symmetry 2021, 13, 1200 .
AMA StyleInga Garbarienė, Vadimas Dudoitis, Vidmantas Ulevičius, Kristina Plauškaitė-Šukienė, Artūras Kilikevičius, Jonas Matijošius, Alfredas Rimkus, Kristina Kilikevičienė, Darius Vainorius, Algirdas Maknickas, Sergejus Borodinas, Steigvilė Byčenkienė. Application of Acoustic Agglomeration Technology to Improve the Removal of Submicron Particles from Vehicle Exhaust. Symmetry. 2021; 13 (7):1200.
Chicago/Turabian StyleInga Garbarienė; Vadimas Dudoitis; Vidmantas Ulevičius; Kristina Plauškaitė-Šukienė; Artūras Kilikevičius; Jonas Matijošius; Alfredas Rimkus; Kristina Kilikevičienė; Darius Vainorius; Algirdas Maknickas; Sergejus Borodinas; Steigvilė Byčenkienė. 2021. "Application of Acoustic Agglomeration Technology to Improve the Removal of Submicron Particles from Vehicle Exhaust." Symmetry 13, no. 7: 1200.
This paper focuses on the dynamic effects of flexible propellers on F2 class aircraft models. An oscillating propeller affects an engine’s mechanical performance, and this combination has a huge influence on the model’s flight dynamic performance. In the first and second sections of this paper, two physical tests that were performed according to the test results obtained using a CFX numerical model are discussed. The studies on flexible propellers for class F2 aircraft models performed in this paper show that, when the first resonant frequencies of the propeller are within the operating range of the aircraft, better flight parameters are achieved. This study helps to explain the effect of a glass composite’s Young’s modulus on the mechanical behavior of a physical propeller in operating conditions and the effect of propeller stiffness on flapping propeller dynamics and unsteady aerodynamics.
Vytautas Rimša; Artūras Kilikevičius. Investigation of the Effect of a Flapping Propeller on Its Aerodynamic Performance. Mathematics 2021, 9, 1182 .
AMA StyleVytautas Rimša, Artūras Kilikevičius. Investigation of the Effect of a Flapping Propeller on Its Aerodynamic Performance. Mathematics. 2021; 9 (11):1182.
Chicago/Turabian StyleVytautas Rimša; Artūras Kilikevičius. 2021. "Investigation of the Effect of a Flapping Propeller on Its Aerodynamic Performance." Mathematics 9, no. 11: 1182.
Research institutions and industrial enterprises demand high accuracy and precision positioning systems to fulfil cutting edge requirements of up-to-date technological processes in the field of metrology and optical fabrication. Linear motor system design with high performance mechanical guiding system and optical encoder ensures nanometer scale precision and constant static error, which can be calibrated by optical instruments. Mechanical guiding systems has its benefits in case of control theory and its stability; unfortunately, on the other hand, there exists high influence of structure geometry and tribological effects such as friction and modal response. The aforementioned effect cannot be straightforwardly identified during the assembly process. Degradation of dynamic units can be detected only after certain operating time. Single degree of freedom systems are well investigated and the effect of degradation can be predicted, but there exists a gap in the analysis of nanometer scale multi degree of freedom dynamic systems; therefore, novel diagnostic tools need to be proposed. In this particular paper, dual axes dynamic system analysis will be presented. The main idea is to decouple standard stacked XY stage and analyse X and Y configuration as two different configurations of the same object, while imitators of corresponding axes are absolutely solid and stationary. As storage and analysis of time domain data is not efficient, main attention will be concentrated on frequency domain data, while, of course, statistical and graphical representation of dynamic response will be presented. Transfer function, dynamic response, spectral analysis of dynamic response, and modal analysis will be presented and discussed. Based on the collected data and its analysis, comparison of X and Y responses to different velocity excitation will be presented. Finally, conclusions and recommendations of novel diagnostic way will be presented.
Artur Piščalov; Edgaras Urbonas; Darius Vainorius; Jonas Matijošius; Artūras Kilikevičius. Investigation of X and Y Configuration Modal and Dynamic Response to Velocity Excitation of the Nanometer Resolution Linear Servo Motor Stage with Quasi-Industrial Guiding System in Quasi-Stable State. Mathematics 2021, 9, 951 .
AMA StyleArtur Piščalov, Edgaras Urbonas, Darius Vainorius, Jonas Matijošius, Artūras Kilikevičius. Investigation of X and Y Configuration Modal and Dynamic Response to Velocity Excitation of the Nanometer Resolution Linear Servo Motor Stage with Quasi-Industrial Guiding System in Quasi-Stable State. Mathematics. 2021; 9 (9):951.
Chicago/Turabian StyleArtur Piščalov; Edgaras Urbonas; Darius Vainorius; Jonas Matijošius; Artūras Kilikevičius. 2021. "Investigation of X and Y Configuration Modal and Dynamic Response to Velocity Excitation of the Nanometer Resolution Linear Servo Motor Stage with Quasi-Industrial Guiding System in Quasi-Stable State." Mathematics 9, no. 9: 951.
Damage to the running surfaces of wheels on railways poses a threat to road safety. They can lead to accidents and disasters. Wheels with a flat spot are the biggest threat. The paper reviews problems that arise when wheels with a flat spot come into contact with a rail, and the methods of their detection and diagnosis. However, the known methods for their determination are still very complex and not precise enough. The research presented is based on previous theoretical studies, during which a simplified mathematical model of the normal force arising from the contact of a wheel with a flat spot with a rail, assuming that as a result of this, a change in sound power is caused was developed and theoretical calculations were performed. It theoretically determined wheel damage during rolling caused by wheel-induced changes in associated sound power, i.e., preliminary values of diagnostic parameters and applied methods. Although initial theoretical research already exists, there was a lack of physical experiments to support the validity of the results of the theoretical model. This work presents the original plan and methodology of the physical experiment performed. A physical experiment performed with the ATLAS LG system and sound pressure measuring equipment showed the suitability and applicability of the theoretical model for the determination of wheel damage.
Vladas Kukėnas; Raimondas Jasevičius; Viačeslav Petrenko; Artūras Kilikevičius; Darius Vainorius. Analysis of Sound Power Level Changes Caused by Wheel with Flat Spot Using Numerical and Physical Experiment. Applied Sciences 2021, 11, 2141 .
AMA StyleVladas Kukėnas, Raimondas Jasevičius, Viačeslav Petrenko, Artūras Kilikevičius, Darius Vainorius. Analysis of Sound Power Level Changes Caused by Wheel with Flat Spot Using Numerical and Physical Experiment. Applied Sciences. 2021; 11 (5):2141.
Chicago/Turabian StyleVladas Kukėnas; Raimondas Jasevičius; Viačeslav Petrenko; Artūras Kilikevičius; Darius Vainorius. 2021. "Analysis of Sound Power Level Changes Caused by Wheel with Flat Spot Using Numerical and Physical Experiment." Applied Sciences 11, no. 5: 2141.
Climatic conditions, such as hail, strongly affect the efficiency of photovoltaic (PV) modules. The aim of this paper is to present comprehensive analytical and experimental research results and to evaluate the impact of hail on PV modules. The experimental study was conducted using a new approach in hail simulation testing the impact on PV modules. The impact of hail was compared using mechanical parameters, which were in turn reflected by electric power produced by a PV module. Based on both simulation and experimental results, optimization guidelines were proposed to improve mechanical resistance of PV modules. The scientific novelty of the article is the optimization of the theoretical model of the PV element based on experimental data. Mechanical impact parameters in PV modules, such as force transmission and final stress, decreased from 236 kN/m2 to 109.8 kN/m2 during the optimization process (geometry packages to obtain the lowest stresses).
Vytautas Makarskas; Mindaugas Jurevičius; Janis Zakis; Artūras Kilikevičius; Sergejus Borodinas; Jonas Matijošius; Kristina Kilikevičienė. Investigation of the influence of hail mechanical impact parameters on photovoltaic modules. Engineering Failure Analysis 2021, 124, 105309 .
AMA StyleVytautas Makarskas, Mindaugas Jurevičius, Janis Zakis, Artūras Kilikevičius, Sergejus Borodinas, Jonas Matijošius, Kristina Kilikevičienė. Investigation of the influence of hail mechanical impact parameters on photovoltaic modules. Engineering Failure Analysis. 2021; 124 ():105309.
Chicago/Turabian StyleVytautas Makarskas; Mindaugas Jurevičius; Janis Zakis; Artūras Kilikevičius; Sergejus Borodinas; Jonas Matijošius; Kristina Kilikevičienė. 2021. "Investigation of the influence of hail mechanical impact parameters on photovoltaic modules." Engineering Failure Analysis 124, no. : 105309.
Linear displacement measuring systems, like optical encoders, are widely used in various precise positioning applications to form a full closed-loop control system. Thus, the performance of the machine and the quality of its technological process are highly dependent on the accuracy of the linear encoder used. Thermoelastic deformation caused by a various thermal sources and the changing ambient temperature are important factors that introduce errors in an encoder reading. This work presents an experimental realization of the real-time geometric and thermal error compensation of the optical linear encoder. The implemented compensation model is based on the approximation of the tested encoder error by a simple parametric function and calculation of a linear nature error component according to an ambient temperature variation. The calculation of a two-dimensional compensation function and the real-time correction of the investigated linear encoder position readings are realized by using a field programmable gate array (FPGA) computing platform. The results of the performed experimental research verified that the final positioning error could be reduced up to 98%.
Donatas Gurauskis; Artūras Kilikevičius; Albinas Kasparaitis. Thermal and Geometric Error Compensation Approach for an Optical Linear Encoder. Sensors 2021, 21, 360 .
AMA StyleDonatas Gurauskis, Artūras Kilikevičius, Albinas Kasparaitis. Thermal and Geometric Error Compensation Approach for an Optical Linear Encoder. Sensors. 2021; 21 (2):360.
Chicago/Turabian StyleDonatas Gurauskis; Artūras Kilikevičius; Albinas Kasparaitis. 2021. "Thermal and Geometric Error Compensation Approach for an Optical Linear Encoder." Sensors 21, no. 2: 360.
Modern industrial enterprises require high accuracy and precision feedback systems to fulfil cutting edge requirements of technological processes. As demand for a highly accurate system grows, a thin gap between throughput and quality exists. The conjunction of ultrafast lasers and modern control strategies of mechatronic systems can be taken into account as an effective solution to reach both throughput and tolerances. In the present paper, the dynamic errors of the moving platform of the one degree of freedom stage, based on linear motor and air bearings, have been analyzed. A precision positioning system is investigated as a symmetric system which is based on symmetric linear motor. The goal of the present article is to investigate the controllers of the different architecture and to find the best controller that can ensure a stable and small dynamic error of the displacement of the stage platform at four different constant velocities of the moving platform. The relations between the controller order, velocity and the displacement dynamic error have been investigated. It is determined that higher-order controllers can reduce the dynamic error significantly at low velocities of the moving platforms: 1 and 5 mm/s. On the contrary, the low order controllers of 4th-degree polynomials of the transfer function can also provide small dynamic errors of the displacement of the platform.
Artur Piščalov; Edgaras Urbonas; Nikolaj Višniakov; Darius Zabulionis; Artūras Kilikevičius. Investigation of Position and Velocity Stability of the Nanometer Resolution Linear Motor Stage with Air Bearings by Shaping of Controller Transfer Function. Symmetry 2020, 12, 2062 .
AMA StyleArtur Piščalov, Edgaras Urbonas, Nikolaj Višniakov, Darius Zabulionis, Artūras Kilikevičius. Investigation of Position and Velocity Stability of the Nanometer Resolution Linear Motor Stage with Air Bearings by Shaping of Controller Transfer Function. Symmetry. 2020; 12 (12):2062.
Chicago/Turabian StyleArtur Piščalov; Edgaras Urbonas; Nikolaj Višniakov; Darius Zabulionis; Artūras Kilikevičius. 2020. "Investigation of Position and Velocity Stability of the Nanometer Resolution Linear Motor Stage with Air Bearings by Shaping of Controller Transfer Function." Symmetry 12, no. 12: 2062.
In the paper, a novel technique for highly dispersed pyrochlore Y2Ti2O7 is proposed. The experimental results proved that the application of microwave irradiation at a certain stage of calcination allowed synthesizing of Y2Ti2O7 in much shorter time, which ensured substantial energy savings. An increase up to 98 wt.% in the content of the preferred phase with a pyrochlore-type structure Y2Ti2O7 was obtained after 25 h of yttrium and titanium oxides calcination at a relatively low temperature of 1150 °C, while the microwave-supported process took only 9 h and provided 99 wt.% of pyrochlore. The proposed technology is suitable for industrial applications, enabling the fabrication of large industrial amounts of pyrochlore without solvent chemistry and high-energy mills. It reduced the cost of both equipment and energy and made the process more environmentally friendly. The particle size and morphology did not change significantly; therefore, the microwave-assisted method can fully replace the traditional one.
Vladimir Chishkala; Serhiy Lytovchenko; Bohdan Mazilin; Edwin Gevorkyan; Vladimir Shkuropatenko; Viktor Voyevodin; Mirosław Rucki; Zbigniew Siemiątkowski; Jonas Matijošius; Agnieszka Dudziak; Jacek Caban; Artūras Kilikevičius. Novel Microwave-Assisted Method of Y2Ti2O7 Powder Synthesis. Materials 2020, 13, 5621 .
AMA StyleVladimir Chishkala, Serhiy Lytovchenko, Bohdan Mazilin, Edwin Gevorkyan, Vladimir Shkuropatenko, Viktor Voyevodin, Mirosław Rucki, Zbigniew Siemiątkowski, Jonas Matijošius, Agnieszka Dudziak, Jacek Caban, Artūras Kilikevičius. Novel Microwave-Assisted Method of Y2Ti2O7 Powder Synthesis. Materials. 2020; 13 (24):5621.
Chicago/Turabian StyleVladimir Chishkala; Serhiy Lytovchenko; Bohdan Mazilin; Edwin Gevorkyan; Vladimir Shkuropatenko; Viktor Voyevodin; Mirosław Rucki; Zbigniew Siemiątkowski; Jonas Matijošius; Agnieszka Dudziak; Jacek Caban; Artūras Kilikevičius. 2020. "Novel Microwave-Assisted Method of Y2Ti2O7 Powder Synthesis." Materials 13, no. 24: 5621.
In the paper, the results of experimental investigations of ion implanted cutting tools performance are presented. The tools, made out of Si3N4 with additives typically used for turning of Ti-6Al-4V alloy, underwent implantation with ions of yttrium (Y+) and rhenium (Re+) using the metal vapor vacuum arc method. Distribution of ions on the tool surface was measured. The cutting tools were tested in turning process with measurement of cutting forces and analysis of wear. A rather unexpected result was the increased wear of the tool after Y+ implantation with 1 × 1017 ion/cm2. It was demonstrated, however, that the tool after Y+ 2 × 1017 ion/cm2 ion implantation provided the best machining performance.
Dmitrij Morozow; Zbigniew Siemiątkowski; Edwin Gevorkyan; Mirosław Rucki; Jonas Matijošius; Artūras Kilikevičius; Jacek Caban; Zbigniew Krzysiak. Effect of Yttrium and Rhenium Ion Implantation on the Performance of Nitride Ceramic Cutting Tools. Materials 2020, 13, 4687 .
AMA StyleDmitrij Morozow, Zbigniew Siemiątkowski, Edwin Gevorkyan, Mirosław Rucki, Jonas Matijošius, Artūras Kilikevičius, Jacek Caban, Zbigniew Krzysiak. Effect of Yttrium and Rhenium Ion Implantation on the Performance of Nitride Ceramic Cutting Tools. Materials. 2020; 13 (20):4687.
Chicago/Turabian StyleDmitrij Morozow; Zbigniew Siemiątkowski; Edwin Gevorkyan; Mirosław Rucki; Jonas Matijošius; Artūras Kilikevičius; Jacek Caban; Zbigniew Krzysiak. 2020. "Effect of Yttrium and Rhenium Ion Implantation on the Performance of Nitride Ceramic Cutting Tools." Materials 13, no. 20: 4687.
This paper presents the experimental results of Cu-Nb wire joining upon applying flash welding technology. The present research is aimed at investigating the structure, electrical and mechanical properties of butt welding joints of Cu-Nb conductors, usable for coils of pulsed magnetic systems. The butt joint structure was found to be free of welding defects. The structure of the butt welded joint provides an insignificant increase in electrical resistance and sufficient ultimate strength and plasticity of the joint. The tensile strength of the welded sample reaches 630 MPa.
Nikolaj Višniakov; Jelena Škamat; Olegas Černašėjus; Artūras Kilikevičius. Flash Welding of Microcomposite Wires for Pulsed Power Applications. Metals 2020, 10, 1053 .
AMA StyleNikolaj Višniakov, Jelena Škamat, Olegas Černašėjus, Artūras Kilikevičius. Flash Welding of Microcomposite Wires for Pulsed Power Applications. Metals. 2020; 10 (8):1053.
Chicago/Turabian StyleNikolaj Višniakov; Jelena Škamat; Olegas Černašėjus; Artūras Kilikevičius. 2020. "Flash Welding of Microcomposite Wires for Pulsed Power Applications." Metals 10, no. 8: 1053.
The strength and stiffness of the frame is one of the key indicators of vehicle structures. Insufficient stiffness causes vibration and noise, and is also less comfortable for both the passengers and the driver. Symmetry is required between the strength and comfort of the structural frame, which depends on vibration and noise. This article analyses the frame of the structure of a medium-sized passenger bus and its dynamic properties, when replacing materials of structural elements which do not affect the symmetry of the structure. The conducted theoretical and experimental modal analysis of the bus, allows for evaluating dynamic parameters and validating the theoretical model based on the experimental results. The optimization of the medium-sized passenger bus frame—by replacing the material of the ancillary frame elements with fiberglass—reveals that its dynamic characteristics change by up to 20%, comparing the values of the first three resonant frequencies with those of the steel structure. The obtained results show that replacing the material of ancillary frame elements with fiberglass, while maintaining the symmetrical arrangement of the elements in the structure, does not change the safety characteristics of the structure, reducing the mass of the frame by 11%, and shifting the coordinate of the centre of gravity vertically downwards, which is very important for stability, comfort and fuel consumption.
Tautvydas Pravilonis; Edgar Sokolovskij; Artūras Kilikevičius; Jonas Matijošius; Kristina Kilikevičienė. The Usage of Alternative Materials to Optimize Bus Frame Structure. Symmetry 2020, 12, 1010 .
AMA StyleTautvydas Pravilonis, Edgar Sokolovskij, Artūras Kilikevičius, Jonas Matijošius, Kristina Kilikevičienė. The Usage of Alternative Materials to Optimize Bus Frame Structure. Symmetry. 2020; 12 (6):1010.
Chicago/Turabian StyleTautvydas Pravilonis; Edgar Sokolovskij; Artūras Kilikevičius; Jonas Matijošius; Kristina Kilikevičienė. 2020. "The Usage of Alternative Materials to Optimize Bus Frame Structure." Symmetry 12, no. 6: 1010.
Smoothness of tape movement and stability of the tape area where elements are generated are very important in precision mechatronic devices where precise elements are generated on a steel tape, controlling them in real time. During movement, deformations and vibrations form in the steel tape area where elements are generated as a result of imperfections of movement equipment, contact between the roller surface and the tape, and errors arising in the movement process. This article is based on the need for a detailed theoretical and experimental research of the effects occurring during the movement of the precision steel tape used in measuring systems with precision elements generated on the tape, including an investigation of the roller-tape contact. The article also aims to develop a model of the system for measuring the displacement of the tape in a raster formation device, to investigate and assess possible effects of external and internal factors on steel tape parameters. The article presents experimental research conducted for determining dynamic variables forming during the movement of a steel tape, assessing the factors that may cause raster generation errors in dynamic mode.
Antanas Fursenko; Artūras Kilikevičius; Kristina Kilikevičienė; Sergejus Borodinas; Albinas Kasparaitis; Jonas Matijošius. Investigation of Roller-Tape Contact Pair Used in Precision Mechatronic System. Applied Sciences 2020, 10, 4041 .
AMA StyleAntanas Fursenko, Artūras Kilikevičius, Kristina Kilikevičienė, Sergejus Borodinas, Albinas Kasparaitis, Jonas Matijošius. Investigation of Roller-Tape Contact Pair Used in Precision Mechatronic System. Applied Sciences. 2020; 10 (11):4041.
Chicago/Turabian StyleAntanas Fursenko; Artūras Kilikevičius; Kristina Kilikevičienė; Sergejus Borodinas; Albinas Kasparaitis; Jonas Matijošius. 2020. "Investigation of Roller-Tape Contact Pair Used in Precision Mechatronic System." Applied Sciences 10, no. 11: 4041.
In this paper, authors have investigated wave distribution caused by the mechanical structure of a passenger bus body frame and its parameters based on the theory of covariance functions. Authors have measured the intensity of vibrations at fixed points. Time scale analyses were conducted based on data arrays (matrixes). The estimates of covariance functions clearly showed that changes in the state of the bus mechanical structure invariably impact changes of the intensity of vibration signals at the relevant points. In the analysis, software Matlab 7 was applied.
Artūras Kilikevičius; Kristina Kilikevičienė; Antanas Fursenko; Jonas Matijošius. The Analysis of Vibration Signals of Critical Points of the Bus Body Frame. Periodica Polytechnica Transportation Engineering 2020, 48, 296 -304.
AMA StyleArtūras Kilikevičius, Kristina Kilikevičienė, Antanas Fursenko, Jonas Matijošius. The Analysis of Vibration Signals of Critical Points of the Bus Body Frame. Periodica Polytechnica Transportation Engineering. 2020; 48 (3):296-304.
Chicago/Turabian StyleArtūras Kilikevičius; Kristina Kilikevičienė; Antanas Fursenko; Jonas Matijošius. 2020. "The Analysis of Vibration Signals of Critical Points of the Bus Body Frame." Periodica Polytechnica Transportation Engineering 48, no. 3: 296-304.
Bringing together the experience and knowledge of engineers allowed building modern footbridges as very slender structures. This in turn has led to structural vibration problems, which is a direct consequence of slender structures. In some footbridges, this problem occurs when natural construction frequencies are close to excitation frequencies. This requires a design methodology, which would ensure user safety and convenience of use of the footbridge in operation. Considering the aforementioned dynamic response, the analysis of the finite element model of a footbridge was conducted focusing on critical acceleration and deformation meanings. The model was based on the footbridge prototype located in Vilnius, Lithuania. Two different loading methods were developed to investigate the dynamic effects caused by people crossing a footbridge. The comparison of experimental and finite element model (FEM) results revealed that the footbridge in operation is within the limit values of comfort requirements in terms of its vibrations.
Artūras Kilikevičius; Darius Bačinskas; Jaroslaw Selech; Jonas Matijošius; Kristina Kilikevičienė; Darius Vainorius; Dariusz Ulbrich; Dawid Romek. The Influence of Different Loads on the Footbridge Dynamic Parameters. Symmetry 2020, 12, 657 .
AMA StyleArtūras Kilikevičius, Darius Bačinskas, Jaroslaw Selech, Jonas Matijošius, Kristina Kilikevičienė, Darius Vainorius, Dariusz Ulbrich, Dawid Romek. The Influence of Different Loads on the Footbridge Dynamic Parameters. Symmetry. 2020; 12 (4):657.
Chicago/Turabian StyleArtūras Kilikevičius; Darius Bačinskas; Jaroslaw Selech; Jonas Matijošius; Kristina Kilikevičienė; Darius Vainorius; Dariusz Ulbrich; Dawid Romek. 2020. "The Influence of Different Loads on the Footbridge Dynamic Parameters." Symmetry 12, no. 4: 657.
Optical encoders are widely used in applications requiring precise displacement measurement and fluent motion control. To reach high positioning accuracy and repeatability, and to create a more stable speed-control loop, essential attention must be directed to the subdivisional error (SDE) of the used encoder. This error influences the interpolation process and restricts the ability to achieve a high resolution. The SDE could be caused by various factors, such as the particular design of the reading head and the optical scanning principle, quality of the measuring scale, any kind of relative orientation changes between the optical components caused by mechanical vibrations or deformations, or scanning speed. If the distorted analog signals are not corrected before interpolation, it is very important to know the limitations of the used encoder. The methodology described in this paper could be used to determine the magnitude of an SDE and its trend. This method is based on a constant-speed test and does not require high-accuracy reference. The performed experimental investigation of the standard optical linear encoder SDE under different scanning speeds revealed the linear relationship between the tested encoder’s traversing velocity and the error value. A more detailed investigation of the obtained results was done on the basis of fast Fourier transformation (FFT) to understand the physical nature of the SDE, and to consider how to improve the performance of the encoder.
Donatas Gurauskis; Artūras Kilikevičius; Sergejus Borodinas. Experimental Investigation of Linear Encoder’s Subdivisional Errors under Different Scanning Speeds. Applied Sciences 2020, 10, 1766 .
AMA StyleDonatas Gurauskis, Artūras Kilikevičius, Sergejus Borodinas. Experimental Investigation of Linear Encoder’s Subdivisional Errors under Different Scanning Speeds. Applied Sciences. 2020; 10 (5):1766.
Chicago/Turabian StyleDonatas Gurauskis; Artūras Kilikevičius; Sergejus Borodinas. 2020. "Experimental Investigation of Linear Encoder’s Subdivisional Errors under Different Scanning Speeds." Applied Sciences 10, no. 5: 1766.
Mechanical vibrations are probably inevitable and occur in more or less all machine tools and other technological equipment. In case the linear encoder is used for moveable parts positioning in such machines, vibrations could cause additional errors. This paper investigates the dynamic behavior of the optical linear encoder under mechanical vibrations. Potentially the most harmful frequencies are determined experimentally, and the corresponding mode shapes are simulated by using finite element method (FEM). Obtained results describe tested encoder`s construction dynamic response to external excitation and could be used to improve its design.
Donatas Gurauskis; Artūras Kilikevičius. Dynamic Behaviour Analysis of Optical Linear Encoder under Mechanical Vibrations. Mechanics 2020, 26, 35 -41.
AMA StyleDonatas Gurauskis, Artūras Kilikevičius. Dynamic Behaviour Analysis of Optical Linear Encoder under Mechanical Vibrations. Mechanics. 2020; 26 (1):35-41.
Chicago/Turabian StyleDonatas Gurauskis; Artūras Kilikevičius. 2020. "Dynamic Behaviour Analysis of Optical Linear Encoder under Mechanical Vibrations." Mechanics 26, no. 1: 35-41.
In this paper, a mathematical model for projectiles shooting in any direction based on sensors distributed stereoscopically is put forward. It is based on the characteristics of a shock wave around a supersonic projectile and acoustical localization. Wave equations for an acoustic monopole point source of a directed effect used for physical interpretation of pressure as an acoustic phenomenon. Simulation and measurements of novel versatile mechanical and acoustical damping system (silencer), which has both a muzzle break and silencer properties studied in this paper. The use of the proposed damping system can have great influence on the acoustic pressure field intensity from the shooter. A silencer regarded as an acoustic transducer and multi-holes waveguide with a chamber. Wave equations for an acoustic monopole point source of a directed effect used for the physical interpretation of pressure as an acoustic phenomenon. The numerical simulation results of the silencer with different configurations presented allow trends to be established. A measurement chain was used to compare the simulation results with the experimental ones. The modeling and experimental results showed an increase in silencer chamber volume results in a reduction of recorded pressure within the silencer chamber.
Jaroslaw Selech; Artūras Kilikevičius; Kristina Kilikevičienė; Sergejus Borodinas; Jonas Matijošius; Darius Vainorius; Jacek Marcinkiewicz; Zaneta Staszak. Force and Sound Pressure Sensors Used for Modeling the Impact of the Firearm with a Suppressor. Applied Sciences 2020, 10, 961 .
AMA StyleJaroslaw Selech, Artūras Kilikevičius, Kristina Kilikevičienė, Sergejus Borodinas, Jonas Matijošius, Darius Vainorius, Jacek Marcinkiewicz, Zaneta Staszak. Force and Sound Pressure Sensors Used for Modeling the Impact of the Firearm with a Suppressor. Applied Sciences. 2020; 10 (3):961.
Chicago/Turabian StyleJaroslaw Selech; Artūras Kilikevičius; Kristina Kilikevičienė; Sergejus Borodinas; Jonas Matijošius; Darius Vainorius; Jacek Marcinkiewicz; Zaneta Staszak. 2020. "Force and Sound Pressure Sensors Used for Modeling the Impact of the Firearm with a Suppressor." Applied Sciences 10, no. 3: 961.
The impact of hail ice cubes on composite structures (such as solar cells) causes actual defects. This article presents a series of tests, in which solar cell modules were exposed to hail simulation testbed balls, allowing to assess the following: the impact energy, which causes the major defects in solar cells; the formed micro-cracks in the structure of solar cells, resulting in the loss of power generated by a solar cell; and the solar cell parameters necessary for modelling. In addition, this article presents a digital analysis of hail simulation. Information received from the digital analysis was used to optimize the structure of solar cells in order to improve its resistance properties. The aim of this study was to present a simple method for experimental hail simulation. The proposed hail impact estimation method can be successfully applied to study the influence of the mechanical–dynamic impact of photovoltaic (PV) modules of different structures on the technical characteristics of these modules (structural stability, power generation, etc.). The study showed that PV modules are subjected to an irreversible effect of the excitation force (i.e., micro-cracking) and it can reduce the generated power by 2.33% to 4.83%.
Kristina Kilikevičienė; Jonas Matijošius; Artūras Kilikevičius; Mindaugas Jurevičius; Vytautas Makarskas; Jacek Caban; Andrzej Marczuk. Research of the Energy Losses of Photovoltaic (PV) Modules after Hail Simulation Using a Newly-Created Testbed. Energies 2019, 12, 4537 .
AMA StyleKristina Kilikevičienė, Jonas Matijošius, Artūras Kilikevičius, Mindaugas Jurevičius, Vytautas Makarskas, Jacek Caban, Andrzej Marczuk. Research of the Energy Losses of Photovoltaic (PV) Modules after Hail Simulation Using a Newly-Created Testbed. Energies. 2019; 12 (23):4537.
Chicago/Turabian StyleKristina Kilikevičienė; Jonas Matijošius; Artūras Kilikevičius; Mindaugas Jurevičius; Vytautas Makarskas; Jacek Caban; Andrzej Marczuk. 2019. "Research of the Energy Losses of Photovoltaic (PV) Modules after Hail Simulation Using a Newly-Created Testbed." Energies 12, no. 23: 4537.
This paper discusses about the scatter of the intensity of vibration signals of paper prints and analyses their mechanical parameters applying the theory of covariance functions. It is an important practical problem, before starting printing process of colour prints, expecting the correct position of fixed raster points, to adjust the paper sheet tension between printing machine sections. The results of measuring the intensity of vibration signals at the fixed points were presented on a time scale in the form of arrays (matrices). The estimates of cross-covariance functions between digital arrays result in measuring the intensity of vibrations, and the estimates of auto-covariance functions of single arrays were calculated upon changing the quantization interval on the time scale. Application of normed auto-covariance and cross-covariance functions enables reduction of preprinting experimental measurements, which saves time (what is actual for industry). Tension force depends on the mechanical properties of the paper sheet and print. These characteristics depend on paper type, layers of printing colors and positioning of the coverage. In the calculation, the software Matlab 7 in batch statement environment was applied.
Arturas Kilikevicius; Mindaugas Jurevicius; Robertas Urbanavicius; Vytautas Turla; Kristina Kilikeviciene; Antanas Fursenko. Vibration measurements of paper prints and the data analysis. Nordic Pulp & Paper Research Journal 2019, 35, 115 -123.
AMA StyleArturas Kilikevicius, Mindaugas Jurevicius, Robertas Urbanavicius, Vytautas Turla, Kristina Kilikeviciene, Antanas Fursenko. Vibration measurements of paper prints and the data analysis. Nordic Pulp & Paper Research Journal. 2019; 35 (1):115-123.
Chicago/Turabian StyleArturas Kilikevicius; Mindaugas Jurevicius; Robertas Urbanavicius; Vytautas Turla; Kristina Kilikeviciene; Antanas Fursenko. 2019. "Vibration measurements of paper prints and the data analysis." Nordic Pulp & Paper Research Journal 35, no. 1: 115-123.