E. A. Pane, Ferdy Hidayat, H. Sukma, Ismail Ismail
This research analyzes the impeller design performance that has been modified based on previous impeller designs. The previous impeller design used high engine power consumption due to the total head, so the modification of the impeller design is expected to reduce the engine power consumption. The existing design and the modified impeller design with the addition of the junction disc plate are used by this research. This research used experiment methods and theoretical methods to compare both of impeller design performances. The experiment method measures total head, fluid capacity, engine speed, and engine power consumption. The theoretical method analyzes actual fluid velocity, specific velocity, total suction head, NPSH, and pump efficiency. The results showed that the fluid flow rate was able to increase the efficiency of the centrifugal pump by 2.8%. The conclusion explains that the addition of a junction disc plate produces energy from a steady fluid flow rate to reduce the engine power consumption and escalation of pump efficiency.
{"title":"Investigation of the Performance of a Centrifugal Pump Impeller Design with the Addition of a Junction Disc Plate","authors":"E. A. Pane, Ferdy Hidayat, H. Sukma, Ismail Ismail","doi":"10.3311/ppme.21081","DOIUrl":"https://doi.org/10.3311/ppme.21081","url":null,"abstract":"This research analyzes the impeller design performance that has been modified based on previous impeller designs. The previous impeller design used high engine power consumption due to the total head, so the modification of the impeller design is expected to reduce the engine power consumption. The existing design and the modified impeller design with the addition of the junction disc plate are used by this research. This research used experiment methods and theoretical methods to compare both of impeller design performances. The experiment method measures total head, fluid capacity, engine speed, and engine power consumption. The theoretical method analyzes actual fluid velocity, specific velocity, total suction head, NPSH, and pump efficiency. The results showed that the fluid flow rate was able to increase the efficiency of the centrifugal pump by 2.8%. The conclusion explains that the addition of a junction disc plate produces energy from a steady fluid flow rate to reduce the engine power consumption and escalation of pump efficiency.","PeriodicalId":43630,"journal":{"name":"PERIODICA POLYTECHNICA-MECHANICAL ENGINEERING","volume":"17 1","pages":""},"PeriodicalIF":1.3,"publicationDate":"2023-04-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84768417","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Nowadays, short fiber-reinforced composites are broadly used in modern restorative dentistry. The tensile strength, Young's modulus, density, and polymerization shrinkage of these materials are developed to mimic the original teeth tissue best. The shrinkage, however, will occur during any polymerization process, which can cause residual stress and gap formation between the tooth and the filling. These can lead to the propagation of cracks, reduction in the adhesive bond strength, or even cause separation in the restoration. During this research, a biomimetic dental restoration was created on a surgically removed third molar with EverX short-fiber reinforced dental composite by bulk-filling technique. The restored tooth sample was examined by X-ray computed tomography to obtain a 3D image of the whole restoration. The volume of the used adhesive, the material discontinuities, and internal cavities were determined. A cut-out slice was further investigated by scanning electron microscopy to examine the adhesive layer thickness, the gap formation, and the quality of the filling. Finally, microtensile specimens were machined to evaluate the bond strength between the tooth dentin and the filling material.
{"title":"Structural and Mechanical Investigation of Class I Biomimetic Composite Dental Filling by X-ray Computed Tomography, Scanning Electron Microscopy, and Microtensile Bond Strength Testing","authors":"","doi":"10.3311/ppme.22025","DOIUrl":"https://doi.org/10.3311/ppme.22025","url":null,"abstract":"Nowadays, short fiber-reinforced composites are broadly used in modern restorative dentistry. The tensile strength, Young's modulus, density, and polymerization shrinkage of these materials are developed to mimic the original teeth tissue best. The shrinkage, however, will occur during any polymerization process, which can cause residual stress and gap formation between the tooth and the filling. These can lead to the propagation of cracks, reduction in the adhesive bond strength, or even cause separation in the restoration. During this research, a biomimetic dental restoration was created on a surgically removed third molar with EverX short-fiber reinforced dental composite by bulk-filling technique. The restored tooth sample was examined by X-ray computed tomography to obtain a 3D image of the whole restoration. The volume of the used adhesive, the material discontinuities, and internal cavities were determined. A cut-out slice was further investigated by scanning electron microscopy to examine the adhesive layer thickness, the gap formation, and the quality of the filling. Finally, microtensile specimens were machined to evaluate the bond strength between the tooth dentin and the filling material.","PeriodicalId":43630,"journal":{"name":"PERIODICA POLYTECHNICA-MECHANICAL ENGINEERING","volume":"13 1","pages":""},"PeriodicalIF":1.3,"publicationDate":"2023-04-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"91211363","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
In this paper, we investigate the reverse motion of a car-trailer combination. The single track model of the vehicle is used with quasi-static tire model to design a simple linear feedback controller that can achieve stable reversing motion along a straight path. The linear stability of the closed-loop system is analyzed by constructing stability charts in the plane of the control gains. The effect of the reversing speed of the vehicle on the stability is also shown. In order to validate the theoretical results, laboratory experiments are carried out using a small-scale vehicle and a conveyor belt.
{"title":"Linear Stability of Reversing a Car-trailer Combination","authors":"Levente Mihályi, D. Takács","doi":"10.3311/ppme.18971","DOIUrl":"https://doi.org/10.3311/ppme.18971","url":null,"abstract":"In this paper, we investigate the reverse motion of a car-trailer combination. The single track model of the vehicle is used with quasi-static tire model to design a simple linear feedback controller that can achieve stable reversing motion along a straight path. The linear stability of the closed-loop system is analyzed by constructing stability charts in the plane of the control gains. The effect of the reversing speed of the vehicle on the stability is also shown. In order to validate the theoretical results, laboratory experiments are carried out using a small-scale vehicle and a conveyor belt.","PeriodicalId":43630,"journal":{"name":"PERIODICA POLYTECHNICA-MECHANICAL ENGINEERING","volume":"50 1","pages":""},"PeriodicalIF":1.3,"publicationDate":"2023-04-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74502931","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
M. Lahlou, A. En-naji, N. Mouhib, B. Saadouki, F. Majid
The aim of this paper is to determine the damage mechanisms of P265GH steel, commonly used for pressure equipment. First, an experimental study using tensile and Charpy tests allowed us to determine the mechanical properties (Young modulus E = 200 GPa, elongation ε = 35%, yield se = 320 MPa, ultimate stress su = 470 MPa, and KIC = 96 MP√m). Then, numerical finite element modeling on a CT specimen using the CASTEM calculation code allowed us to determine the damage of the material when the notch depth varies. The analysis of the results shows that the numerical values of the stress concentration coefficient Kt and the stress intensity factor KI are comparable with the analytically calculated values, thus validating our numerical study. The numerical results obtained revealed that the maximum stress σmax is located in the vicinity of the notch bottom and the high probability density corresponds to a high loading level.
{"title":"A Numerical Study of the Damage Mechanisms for CT Tensile Specimens of P265GH Steel Material","authors":"M. Lahlou, A. En-naji, N. Mouhib, B. Saadouki, F. Majid","doi":"10.3311/ppme.20234","DOIUrl":"https://doi.org/10.3311/ppme.20234","url":null,"abstract":"The aim of this paper is to determine the damage mechanisms of P265GH steel, commonly used for pressure equipment. First, an experimental study using tensile and Charpy tests allowed us to determine the mechanical properties (Young modulus E = 200 GPa, elongation ε = 35%, yield se = 320 MPa, ultimate stress su = 470 MPa, and KIC = 96 MP√m). Then, numerical finite element modeling on a CT specimen using the CASTEM calculation code allowed us to determine the damage of the material when the notch depth varies. The analysis of the results shows that the numerical values of the stress concentration coefficient Kt and the stress intensity factor KI are comparable with the analytically calculated values, thus validating our numerical study. The numerical results obtained revealed that the maximum stress σmax is located in the vicinity of the notch bottom and the high probability density corresponds to a high loading level.","PeriodicalId":43630,"journal":{"name":"PERIODICA POLYTECHNICA-MECHANICAL ENGINEERING","volume":"14 1","pages":""},"PeriodicalIF":1.3,"publicationDate":"2023-03-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74843692","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Foul water stacks are a separate chapter in the design of sanitary installations, especially in high-rise buildings. The problematic part is the complicated hydraulic conditions in the stacks, which lead to high values of negative pressure and overpressure. Exceeding the maximum negative pressure values leads to the extraction of water from the traps, which causes the spread of annoying smells in the interior. Another problematic part is the high hydraulic jumps caused by a sudden change in the velocity of water in the stack, especially above the change in the direction of stacks. Such sudden changes in velocity cause excessive vibrations and noise that spread from stacks to the building structures and surrounding areas. The contribution deals with the issue of hydraulic conditions in the flow of foul water in stacks, assessment of the maximum values of negative pressure and overpressure, technical solutions that ensure optimal water flow in the drainage systems of buildings. Based on measurements that were performed in companies abroad, the authors prepared graphs of pressure fluctuations in stacks for selected boundary conditions.
{"title":"Hydraulic Conditions in Foul Water Stacks","authors":"Martin Sokol, J. Peráčková","doi":"10.3311/ppme.19904","DOIUrl":"https://doi.org/10.3311/ppme.19904","url":null,"abstract":"Foul water stacks are a separate chapter in the design of sanitary installations, especially in high-rise buildings. The problematic part is the complicated hydraulic conditions in the stacks, which lead to high values of negative pressure and overpressure. Exceeding the maximum negative pressure values leads to the extraction of water from the traps, which causes the spread of annoying smells in the interior. Another problematic part is the high hydraulic jumps caused by a sudden change in the velocity of water in the stack, especially above the change in the direction of stacks. Such sudden changes in velocity cause excessive vibrations and noise that spread from stacks to the building structures and surrounding areas. The contribution deals with the issue of hydraulic conditions in the flow of foul water in stacks, assessment of the maximum values of negative pressure and overpressure, technical solutions that ensure optimal water flow in the drainage systems of buildings. Based on measurements that were performed in companies abroad, the authors prepared graphs of pressure fluctuations in stacks for selected boundary conditions.","PeriodicalId":43630,"journal":{"name":"PERIODICA POLYTECHNICA-MECHANICAL ENGINEERING","volume":"26 1","pages":""},"PeriodicalIF":1.3,"publicationDate":"2023-03-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77845259","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Structural simulations of electric motors require precise material models. Laminate stacks that are made of several identical steel sheets are particularly challenging to simulate using FEA. The structural stiffness of laminate stacks usually follows transversal isotropic behavior. Measuring a complete laminate stack used in passenger cars is challenging due to its size and the high testing load needed to reach real loads experienced while in operation. A new method capable of performing such measurements is presented in this article, with the help of equipment normally used for testing structures used in civil engineering. Two sets of exemplary results are presented utilizing this measurement procedure, that were performed on a real automotive rotor laminate stack: axial compression stiffness from a cyclic test, and shear stiffness at various axial preload levels. In the axial compression load case, the loading and unloading curves form a hysteresis, that changes in every test cycle. Shear stiffness shows high dependance on the axial compression preload. After loading and unloading the stack with shear loads, significant plastic deformations remain.
{"title":"A Method for Measuring Normal and Shear Stiffness of Laminate Stacks of Electric Motors","authors":"V. Szabó, D. Harrach, D. Feszty, Balázs Pere","doi":"10.3311/ppme.20505","DOIUrl":"https://doi.org/10.3311/ppme.20505","url":null,"abstract":"Structural simulations of electric motors require precise material models. Laminate stacks that are made of several identical steel sheets are particularly challenging to simulate using FEA. The structural stiffness of laminate stacks usually follows transversal isotropic behavior. Measuring a complete laminate stack used in passenger cars is challenging due to its size and the high testing load needed to reach real loads experienced while in operation. A new method capable of performing such measurements is presented in this article, with the help of equipment normally used for testing structures used in civil engineering. Two sets of exemplary results are presented utilizing this measurement procedure, that were performed on a real automotive rotor laminate stack: axial compression stiffness from a cyclic test, and shear stiffness at various axial preload levels. In the axial compression load case, the loading and unloading curves form a hysteresis, that changes in every test cycle. Shear stiffness shows high dependance on the axial compression preload. After loading and unloading the stack with shear loads, significant plastic deformations remain.","PeriodicalId":43630,"journal":{"name":"PERIODICA POLYTECHNICA-MECHANICAL ENGINEERING","volume":"4 2 1","pages":""},"PeriodicalIF":1.3,"publicationDate":"2023-03-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78856583","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Benedek Szovák, Krisztián Korsós, D. Kemény, Péter Szalva
In this study, the effects of different welding filler materials were examined in the case of repair welding of pressure infiltration casting tool made out of Böhler W350 ISOBLOC hot forming tool steel. Three additional welding filler materials were used: Böhler W350 ISOBLOC (same as the raw material), Böhler W300 ISOBLOC and Anviloy® 1150 tungsten alloy. The welds were created with TIG welding method. The used welding filler material has an impact on the mechanical and corrosive properties of the tool. The hardness of the weld was measured to determine its resistance against mechanical stress. The corrosion rate was measured because molten aluminium corrodes workpieces due to its high chemical activity. It was concluded that a single-pass weld corrosion speed is 0.142 ± 0.010 mm/year while a weld containing multiple layers and passes has the corrosion speed of 0.069 ± 0.005 mm/year which is approximately 48% of the corrosion speed of the single-pass weld. Furthermore, the hardness of a weld made with W350 welding filler material significantly drops in the upper layers of the weld, down to 273 HV1 while the hardness of the base material is 495 ± 8 HV1. The results show that the multiple layers and passes welds have better corrosion resistance and less hardness than the single-pass weld.
{"title":"Effect of the Welding Filler Material on the Mechanical and Corrosive Behavior of Böhler W350 ISOBLOC Hot Forming Tool Steel","authors":"Benedek Szovák, Krisztián Korsós, D. Kemény, Péter Szalva","doi":"10.3311/ppme.21435","DOIUrl":"https://doi.org/10.3311/ppme.21435","url":null,"abstract":"In this study, the effects of different welding filler materials were examined in the case of repair welding of pressure infiltration casting tool made out of Böhler W350 ISOBLOC hot forming tool steel. Three additional welding filler materials were used: Böhler W350 ISOBLOC (same as the raw material), Böhler W300 ISOBLOC and Anviloy® 1150 tungsten alloy. The welds were created with TIG welding method. The used welding filler material has an impact on the mechanical and corrosive properties of the tool. The hardness of the weld was measured to determine its resistance against mechanical stress. The corrosion rate was measured because molten aluminium corrodes workpieces due to its high chemical activity. It was concluded that a single-pass weld corrosion speed is 0.142 ± 0.010 mm/year while a weld containing multiple layers and passes has the corrosion speed of 0.069 ± 0.005 mm/year which is approximately 48% of the corrosion speed of the single-pass weld. Furthermore, the hardness of a weld made with W350 welding filler material significantly drops in the upper layers of the weld, down to 273 HV1 while the hardness of the base material is 495 ± 8 HV1. The results show that the multiple layers and passes welds have better corrosion resistance and less hardness than the single-pass weld.","PeriodicalId":43630,"journal":{"name":"PERIODICA POLYTECHNICA-MECHANICAL ENGINEERING","volume":"83 1","pages":""},"PeriodicalIF":1.3,"publicationDate":"2023-02-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75187937","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
3D printing technologies have developed significantly over the last 30 years, with a major impact on all segments of today's industry. With the introduction of additive manufacturing, product development time can be greatly reduced and printing functional parts directly is also a viable option. Another advantage of additive manufacturing is that it allows greater design freedom than traditional manufacturing technologies. This makes it possible to print products with complex geometries and even different material qualities. In this paper, the authors investigated the effects of printing time, the layer thickness and the orientation on the surface roughness and cylindricity of the printed parts. The aim is to find the combination of layer thickness and part orientation which causes the best results in terms of surface roughness and cylindricity as a function of printing time.
{"title":"The Effect of Layer Thickness and Orientation of the Workpiece on the Micro- and Macrogeometric Properties and the Machining Time of the Part during 3D Printing","authors":"G. Kónya, P. Ficzere","doi":"10.3311/ppme.21473","DOIUrl":"https://doi.org/10.3311/ppme.21473","url":null,"abstract":"3D printing technologies have developed significantly over the last 30 years, with a major impact on all segments of today's industry. With the introduction of additive manufacturing, product development time can be greatly reduced and printing functional parts directly is also a viable option. Another advantage of additive manufacturing is that it allows greater design freedom than traditional manufacturing technologies. This makes it possible to print products with complex geometries and even different material qualities. In this paper, the authors investigated the effects of printing time, the layer thickness and the orientation on the surface roughness and cylindricity of the printed parts. The aim is to find the combination of layer thickness and part orientation which causes the best results in terms of surface roughness and cylindricity as a function of printing time.","PeriodicalId":43630,"journal":{"name":"PERIODICA POLYTECHNICA-MECHANICAL ENGINEERING","volume":"8 1","pages":""},"PeriodicalIF":1.3,"publicationDate":"2023-02-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75491712","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The dynamics of the 1.5-degree-of-freedom model of towed wheel is investigated. Dry friction at the king pin is considered, leading to a non-smooth dynamical system. Beyond analytical and numerical linear stability analysis, the nonlinear vibrations are investigated by numerical bifurcation analysis with smoothing and by numerical simulations with event handling. The effect of dry friction at the king pin on the birth of separated periodic branches is presented on bifurcation diagrams. The presence of bistable parameter domains is also shown. The effect of smoothing is investigated by comparing bifurcation diagrams of the smoothed and the original non-smooth systems.
{"title":"Numerical Analysis on Shimmying Wheels with Dry Friction Damper","authors":"Hanna Zsofia Horvath, D. Takács","doi":"10.3311/ppme.21072","DOIUrl":"https://doi.org/10.3311/ppme.21072","url":null,"abstract":"The dynamics of the 1.5-degree-of-freedom model of towed wheel is investigated. Dry friction at the king pin is considered, leading to a non-smooth dynamical system. Beyond analytical and numerical linear stability analysis, the nonlinear vibrations are investigated by numerical bifurcation analysis with smoothing and by numerical simulations with event handling. The effect of dry friction at the king pin on the birth of separated periodic branches is presented on bifurcation diagrams. The presence of bistable parameter domains is also shown. The effect of smoothing is investigated by comparing bifurcation diagrams of the smoothed and the original non-smooth systems.","PeriodicalId":43630,"journal":{"name":"PERIODICA POLYTECHNICA-MECHANICAL ENGINEERING","volume":"PP 1","pages":""},"PeriodicalIF":1.3,"publicationDate":"2023-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84166965","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
A detailed parameter study is made of chemically active spherical bubbles. The calculations apply an up-to-date chemical mechanism for pure oxygen initial content, taking into account pressure dependency, duplication of chemical reactions, and proper third-body efficiency coefficients. The chemical yield is defined as the amount of substance at the maximum bubble radius, and the dissipated power is approached in a relatively new method. The parameter study focuses on finding the parameter combinations where maximum yield and maximum energy efficiency arise for various chemical species (O3, OH radical, H2 and H2O2). Results show that the locations of maximum yield and efficiency points differ significantly, depending on the chemical species. Usually, neither chemical yield nor efficiency values arise at maximum pressure amplitude and minimum driving frequency (as one would presumably expect).
{"title":"Energy Dissipation and Chemical Yield of an Ultrasound Driven Single Bubble","authors":"Csanád Kalmár, F. Hegedűs","doi":"10.3311/ppme.20360","DOIUrl":"https://doi.org/10.3311/ppme.20360","url":null,"abstract":"A detailed parameter study is made of chemically active spherical bubbles. The calculations apply an up-to-date chemical mechanism for pure oxygen initial content, taking into account pressure dependency, duplication of chemical reactions, and proper third-body efficiency coefficients. The chemical yield is defined as the amount of substance at the maximum bubble radius, and the dissipated power is approached in a relatively new method. The parameter study focuses on finding the parameter combinations where maximum yield and maximum energy efficiency arise for various chemical species (O3, OH radical, H2 and H2O2). Results show that the locations of maximum yield and efficiency points differ significantly, depending on the chemical species. Usually, neither chemical yield nor efficiency values arise at maximum pressure amplitude and minimum driving frequency (as one would presumably expect).","PeriodicalId":43630,"journal":{"name":"PERIODICA POLYTECHNICA-MECHANICAL ENGINEERING","volume":"2 4 1","pages":""},"PeriodicalIF":1.3,"publicationDate":"2023-01-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85114658","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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