TY  - CONF
AU  - Hasan, Mohammad Sakib
AU  - Ivanov, Toni
AU  - Vorkapić, Miloš
PY  - 2021
UR  - https://cer.ihtm.bg.ac.rs/handle/123456789/5659
AB  - In this paper, bone-shaped samples (dogbone) made of thermoplastic polymer PLA were tested according to the ASTM D638 standard. All samples were made on a WANHAO duplicator i3 plus 3D printer. PLA is the most widely used polymer mainly due to its thermoplastic workability and good mechanical properties. The mechanical characteristics of the materials were compared after the realization of the samples on the 3D printer and after the remelting process. All samples were built in horizontal orientation. Remelting process involves stacking / packing samples in a mold and pressing them with sodium chloride (NaCl) powder. Since sodium chloride (NaCl) is a poor conductor of temperature, it takes some time for the experiment to be realized in order to equalize the temperatures throughout the volume of the mold. The mold thus formed was kept at 210°C for 30-45 minutes. The purpose of salt powder molding is to get even curing without deformation on the surfaces of the parts. The samples become rougher after this treatment and it is necessary to remove excess salt from the structure as well as additional surface treatment. The remelting process proved to be very cheap, but also quite unreliable due to the slow and uneven rise in temperature in the mold. The SHIMADZU AGS-X 100 kN tensile testing machine was used to test the tensile strength of the samples. During the experiment, it was found that the samples with remelting process have a much higher tensile strength compared to the untreated samples. Remelting procedure of PLA greatly improves the mechanical properties and gives better performance to complex parts printed on a 3D printer by reducing the anisotropic characteristics of the polymer. Further research would be related to the testing of other thermoplastic materials such as ABS, PET-G etc. It would be interesting to use other materials for molding and to perform a comparative analysis of the obtained results of the new molding methods with the described method of applying salt powder.
PB  - Belgrade : Innovation Center of Faculty of Mechanical Engineering
C3  - Program and the Book of Abstracts - International Conference of Experimental and Numerical Investigations and New Technologies, CNN TECH 2021, 29/06-02/07 2021, Zlatibor, Serbia
T1  - Improvement of mechanical characteristics of PLA by applying remelting process
SP  - 66
EP  - 66
UR  - https://hdl.handle.net/21.15107/rcub_cer_5659
ER  - 

@conference{
author = "Hasan, Mohammad Sakib and Ivanov, Toni and Vorkapić, Miloš",
year = "2021",
abstract = "In this paper, bone-shaped samples (dogbone) made of thermoplastic polymer PLA were tested according to the ASTM D638 standard. All samples were made on a WANHAO duplicator i3 plus 3D printer. PLA is the most widely used polymer mainly due to its thermoplastic workability and good mechanical properties. The mechanical characteristics of the materials were compared after the realization of the samples on the 3D printer and after the remelting process. All samples were built in horizontal orientation. Remelting process involves stacking / packing samples in a mold and pressing them with sodium chloride (NaCl) powder. Since sodium chloride (NaCl) is a poor conductor of temperature, it takes some time for the experiment to be realized in order to equalize the temperatures throughout the volume of the mold. The mold thus formed was kept at 210°C for 30-45 minutes. The purpose of salt powder molding is to get even curing without deformation on the surfaces of the parts. The samples become rougher after this treatment and it is necessary to remove excess salt from the structure as well as additional surface treatment. The remelting process proved to be very cheap, but also quite unreliable due to the slow and uneven rise in temperature in the mold. The SHIMADZU AGS-X 100 kN tensile testing machine was used to test the tensile strength of the samples. During the experiment, it was found that the samples with remelting process have a much higher tensile strength compared to the untreated samples. Remelting procedure of PLA greatly improves the mechanical properties and gives better performance to complex parts printed on a 3D printer by reducing the anisotropic characteristics of the polymer. Further research would be related to the testing of other thermoplastic materials such as ABS, PET-G etc. It would be interesting to use other materials for molding and to perform a comparative analysis of the obtained results of the new molding methods with the described method of applying salt powder.",
publisher = "Belgrade : Innovation Center of Faculty of Mechanical Engineering",
journal = "Program and the Book of Abstracts - International Conference of Experimental and Numerical Investigations and New Technologies, CNN TECH 2021, 29/06-02/07 2021, Zlatibor, Serbia",
title = "Improvement of mechanical characteristics of PLA by applying remelting process",
pages = "66-66",
url = "https://hdl.handle.net/21.15107/rcub_cer_5659"
}

Hasan, M. S., Ivanov, T.,& Vorkapić, M.. (2021). Improvement of mechanical characteristics of PLA by applying remelting process. in Program and the Book of Abstracts - International Conference of Experimental and Numerical Investigations and New Technologies, CNN TECH 2021, 29/06-02/07 2021, Zlatibor, Serbia
Belgrade : Innovation Center of Faculty of Mechanical Engineering., 66-66.
https://hdl.handle.net/21.15107/rcub_cer_5659

Hasan MS, Ivanov T, Vorkapić M. Improvement of mechanical characteristics of PLA by applying remelting process. in Program and the Book of Abstracts - International Conference of Experimental and Numerical Investigations and New Technologies, CNN TECH 2021, 29/06-02/07 2021, Zlatibor, Serbia. 2021;:66-66.
https://hdl.handle.net/21.15107/rcub_cer_5659 .

Hasan, Mohammad Sakib, Ivanov, Toni, Vorkapić, Miloš, "Improvement of mechanical characteristics of PLA by applying remelting process" in Program and the Book of Abstracts - International Conference of Experimental and Numerical Investigations and New Technologies, CNN TECH 2021, 29/06-02/07 2021, Zlatibor, Serbia (2021):66-66,
https://hdl.handle.net/21.15107/rcub_cer_5659 .

TY  - CONF
AU  - Hasan, Mohammad Sakib
AU  - Vorkapić, Miloš
AU  - Ivanov, Toni
AU  - Kovačević, Aleksandar
PY  - 2020
UR  - http://cent.mas.bg.ac.rs/jupiter/index.htm
UR  - https://cer.ihtm.bg.ac.rs/handle/123456789/3903
AB  - U ovom radu, izvršena je analiza i predikcija brzina štampe u eksploatacionim uslovima. Postoje
odstupanja zadane brzine na štampaču od proračunate stvarne vrednosti. S tim u vezi, postoji i razlika u
vremenima izrade. Ovde je posmatrana brzina kao ravnomerno pravolinijsko kretanja brizgaljke. Zato, VNM je
poslužila za predikciju Vsr, sa promenom ulaznih parametara. Za rezultate predikcije brzine dobili smo
zadovoljavajuću vrednost regresionog koeficijenta 0.9999 sa ukupnom MAPE greškom koja iznosi 1,84%. Mreža bi
se mogla koristiti za obradu, predviđanje i optimizaciju prosečne brzine mlaznice i ostalih procesnih parametara.
AB  - In this paper, an analysis and printing speed prediction in exploitation conditions performed. There are set speed deviations of the on the printer from the calculated actual value. In this regard, there is also a difference in manufacturing times. Here, speed viewed as a uniform perpendicular nozzle motion. Therefore, the VNM used the Vsr prediction, with the input parameters changing. For the speed prediction results, we received a satisfactory regression coefficient value of 0.9999 with a total MAPE error of 1.84%. The network could be use for processing, prediction and, nozzle average speed optimization and other process parameters.
PB  - Uniiverzitet u Beogradu - Mašinski fakultet
C3  - Zbornik radova - 42. JUPITER konferencija / Proceedings - 42nd JUPITER Conference
T1  - Predikcija brzine na 3D štampaču primenom veštačkih neuronskih mreža
SP  - 2.7
EP  - 2.12
UR  - https://hdl.handle.net/21.15107/rcub_cer_3903
ER  - 

@conference{
author = "Hasan, Mohammad Sakib and Vorkapić, Miloš and Ivanov, Toni and Kovačević, Aleksandar",
year = "2020",
abstract = "U ovom radu, izvršena je analiza i predikcija brzina štampe u eksploatacionim uslovima. Postoje
odstupanja zadane brzine na štampaču od proračunate stvarne vrednosti. S tim u vezi, postoji i razlika u
vremenima izrade. Ovde je posmatrana brzina kao ravnomerno pravolinijsko kretanja brizgaljke. Zato, VNM je
poslužila za predikciju Vsr, sa promenom ulaznih parametara. Za rezultate predikcije brzine dobili smo
zadovoljavajuću vrednost regresionog koeficijenta 0.9999 sa ukupnom MAPE greškom koja iznosi 1,84%. Mreža bi
se mogla koristiti za obradu, predviđanje i optimizaciju prosečne brzine mlaznice i ostalih procesnih parametara., In this paper, an analysis and printing speed prediction in exploitation conditions performed. There are set speed deviations of the on the printer from the calculated actual value. In this regard, there is also a difference in manufacturing times. Here, speed viewed as a uniform perpendicular nozzle motion. Therefore, the VNM used the Vsr prediction, with the input parameters changing. For the speed prediction results, we received a satisfactory regression coefficient value of 0.9999 with a total MAPE error of 1.84%. The network could be use for processing, prediction and, nozzle average speed optimization and other process parameters.",
publisher = "Uniiverzitet u Beogradu - Mašinski fakultet",
journal = "Zbornik radova - 42. JUPITER konferencija / Proceedings - 42nd JUPITER Conference",
title = "Predikcija brzine na 3D štampaču primenom veštačkih neuronskih mreža",
pages = "2.7-2.12",
url = "https://hdl.handle.net/21.15107/rcub_cer_3903"
}

Hasan, M. S., Vorkapić, M., Ivanov, T.,& Kovačević, A.. (2020). Predikcija brzine na 3D štampaču primenom veštačkih neuronskih mreža. in Zbornik radova - 42. JUPITER konferencija / Proceedings - 42nd JUPITER Conference
Uniiverzitet u Beogradu - Mašinski fakultet., 2.7-2.12.
https://hdl.handle.net/21.15107/rcub_cer_3903

Hasan MS, Vorkapić M, Ivanov T, Kovačević A. Predikcija brzine na 3D štampaču primenom veštačkih neuronskih mreža. in Zbornik radova - 42. JUPITER konferencija / Proceedings - 42nd JUPITER Conference. 2020;:2.7-2.12.
https://hdl.handle.net/21.15107/rcub_cer_3903 .

Hasan, Mohammad Sakib, Vorkapić, Miloš, Ivanov, Toni, Kovačević, Aleksandar, "Predikcija brzine na 3D štampaču primenom veštačkih neuronskih mreža" in Zbornik radova - 42. JUPITER konferencija / Proceedings - 42nd JUPITER Conference (2020):2.7-2.12,
https://hdl.handle.net/21.15107/rcub_cer_3903 .

TY  - JOUR
AU  - Hasan, Mohammad Sakib
AU  - Ivanov, Toni
AU  - Vorkapić, Miloš
AU  - Simonović, Aleksandar
AU  - Daou, David
AU  - Kovačević, Aleksandar
AU  - Milovanović, Aleksa
PY  - 2020
UR  - https://cer.ihtm.bg.ac.rs/handle/123456789/3722
AB  - Rapid innovations in 3D printing technology have allowed highly complex parts to be manufactured quickly and easily, particularly for prototyping purposes. Fused Deposition Modeling of thermoplastic materials is one of the most commonly used techniques in three-dimensional (3D) printing. The major aim of Fused Deposition Modeling (FDM) is to design and manufacture usable parts for fields such as engineering and medicine. Therefore, it is essential to investigate the mechanical properties of such FDM processed structures. One of the most commonly used materials currently on the market is Polylactic Acid (PLA). The main purpose of this paper is to investigate the effects of aging and heat treatment on the tensile properties of PLA printed test specimens. The tensile properties of parts manufactured by the 3D printer are influenced by various parameters such as extrusion temperature, infill density, building direction, layer height, etc. A total of 96 specimens were built by altering building orientation and layer height to estimate and compare the tensile properties of the printed parts. To investigate the aging effect, 30 of 96 specimens were printed 6 months before the tensile experiment. Half of both aged and new specimens were cured in an oven at 57.5 [˚C] for 3 hours while the other half endured no heat treatment. After the performed measurement, it can be concluded that heat treatment generally improves structural strength of the printed parts, while aging decreases it. However, these effects are highly dependent on the layer thickness and printing quality. The tensile test is conducted according to the ASTM D638 standard. The fractured samples were further characterized using an electron microscope.
PB  - Romania : Revista Chimie SRL
T2  - Materiale  Plastice
T1  - Impact of Aging Effect and Heat Treatment on the Tensile Properties of PLA (Poly Lactic Acid) Printed Parts
VL  - 57
IS  - 3
SP  - 147
EP  - 159
DO  - 10.37358/MP.20.3.5389
ER  - 

@article{
author = "Hasan, Mohammad Sakib and Ivanov, Toni and Vorkapić, Miloš and Simonović, Aleksandar and Daou, David and Kovačević, Aleksandar and Milovanović, Aleksa",
year = "2020",
abstract = "Rapid innovations in 3D printing technology have allowed highly complex parts to be manufactured quickly and easily, particularly for prototyping purposes. Fused Deposition Modeling of thermoplastic materials is one of the most commonly used techniques in three-dimensional (3D) printing. The major aim of Fused Deposition Modeling (FDM) is to design and manufacture usable parts for fields such as engineering and medicine. Therefore, it is essential to investigate the mechanical properties of such FDM processed structures. One of the most commonly used materials currently on the market is Polylactic Acid (PLA). The main purpose of this paper is to investigate the effects of aging and heat treatment on the tensile properties of PLA printed test specimens. The tensile properties of parts manufactured by the 3D printer are influenced by various parameters such as extrusion temperature, infill density, building direction, layer height, etc. A total of 96 specimens were built by altering building orientation and layer height to estimate and compare the tensile properties of the printed parts. To investigate the aging effect, 30 of 96 specimens were printed 6 months before the tensile experiment. Half of both aged and new specimens were cured in an oven at 57.5 [˚C] for 3 hours while the other half endured no heat treatment. After the performed measurement, it can be concluded that heat treatment generally improves structural strength of the printed parts, while aging decreases it. However, these effects are highly dependent on the layer thickness and printing quality. The tensile test is conducted according to the ASTM D638 standard. The fractured samples were further characterized using an electron microscope.",
publisher = "Romania : Revista Chimie SRL",
journal = "Materiale  Plastice",
title = "Impact of Aging Effect and Heat Treatment on the Tensile Properties of PLA (Poly Lactic Acid) Printed Parts",
volume = "57",
number = "3",
pages = "147-159",
doi = "10.37358/MP.20.3.5389"
}

Hasan, M. S., Ivanov, T., Vorkapić, M., Simonović, A., Daou, D., Kovačević, A.,& Milovanović, A.. (2020). Impact of Aging Effect and Heat Treatment on the Tensile Properties of PLA (Poly Lactic Acid) Printed Parts. in Materiale  Plastice
Romania : Revista Chimie SRL., 57(3), 147-159.
https://doi.org/10.37358/MP.20.3.5389

Hasan MS, Ivanov T, Vorkapić M, Simonović A, Daou D, Kovačević A, Milovanović A. Impact of Aging Effect and Heat Treatment on the Tensile Properties of PLA (Poly Lactic Acid) Printed Parts. in Materiale  Plastice. 2020;57(3):147-159.
doi:10.37358/MP.20.3.5389 .

Hasan, Mohammad Sakib, Ivanov, Toni, Vorkapić, Miloš, Simonović, Aleksandar, Daou, David, Kovačević, Aleksandar, Milovanović, Aleksa, "Impact of Aging Effect and Heat Treatment on the Tensile Properties of PLA (Poly Lactic Acid) Printed Parts" in Materiale  Plastice, 57, no. 3 (2020):147-159,
https://doi.org/10.37358/MP.20.3.5389 . .

TY  - JOUR
AU  - Vorkapić, Miloš
AU  - Bogetić, Srđan
AU  - Tanović, Dragoljub
AU  - Hasan, Mohammad Sakib
AU  - Kovačević, Aleksandar
PY  - 2019
UR  - https://cer.ihtm.bg.ac.rs/handle/123456789/3470
AB  - In this paper, GAP analysis and 5S tool are applied in the case of realization of a compact pressure
transmitter. GAP analysis, combined with the 5S tool, can qualitatively indicate the critical points
in the manufacturing, assembly and quality control of a finished transmitter. Existing errors lead to
the appearance of possible risks in the realization of production processes, from the input of raw
materials to the assembly of the finished product. In order to eliminate the existing errors, the main
steps of the GAP analysis are described in detail. Guidelines are provided on how to improve the
workplace manufacturing process through certain improvements by applying all 5S elements.
According to the implemented action plan, the main causes of risk occurrence in the GAP analysis
were: human factor and processing technologies. The human factor was characterized by poor
control in the workplace (there is no discipline), poor training and incompetence of employees for
the given tasks. Processing technology involves obsolete machines, which can introduce deviations
of dimensions and tolerances from the prescribed values.
AB  - U ovom radu, analizirani su GAP analiza i 5S alat na primeru realizacije malogabaritnog transmitera pritiska. GAP analiza, u kombinaciji sa 5S alatom, može kvalitetno ukazuje na kritične tačke u procesu proizvodnje, sklapanja i kontrole gotovog transmitera. Postojeće greške dovode do pojave mogućih rizika u realizaciji proizvodnih procesa, od ulaza repromaterijala do sklapanja gotovog proizvoda. Analiza rizika, omogućava organizaciji da preuzme određene korake u prihvatanju ili smanjenju njegovog uticaja. 5S alat u GAP analizi pomaže da se rizična mesta srede i dovedu u funkcionalno stanje, sa što manje gubitaka (otpada). Zbog eliminacije postojećih grešaka, u radu su detaljno opisani glavni koraci GAP analize. Date su smernice kako da se unapredi proces proizvodnje na radnom mestu kroz određena poboljšanja primenom svih 5S elemenata. Prema sprovedenom akcionom planu konstatovano je da su glavni uzročnici pojave rizika u GAP analizi sledeći: ljudski faktor i tehnologije obrade. Ljudski faktor je okarakterisan slabom kontrolom na radnom mestu (ne postoji disciplina), slabom obukom i nekompetentnošću zaposlenih za propisano radno mesto. Tehnologija obrade podrazumeva tehnološki zastarele mašine i odstupanja mera i tolerancija od propisanih vrednosti
PB  - Zrenjanin: University of Novi Sad - 'Mihajlo Pupin' Technical Faculty
T2  - Journal of Engineering Management and Competitiveness (JEM)
T1  - 5S Elements as steps to bridge the gap in transmitter manufacturing process
T1  - 5S elementi kao koraci za premošćivanje procepa u procesu prozvodnje transmitera
VL  - 9
IS  - 2
SP  - 148
EP  - 158
DO  - 10.5937/jemc1902148V
ER  - 

@article{
author = "Vorkapić, Miloš and Bogetić, Srđan and Tanović, Dragoljub and Hasan, Mohammad Sakib and Kovačević, Aleksandar",
year = "2019",
abstract = "In this paper, GAP analysis and 5S tool are applied in the case of realization of a compact pressure
transmitter. GAP analysis, combined with the 5S tool, can qualitatively indicate the critical points
in the manufacturing, assembly and quality control of a finished transmitter. Existing errors lead to
the appearance of possible risks in the realization of production processes, from the input of raw
materials to the assembly of the finished product. In order to eliminate the existing errors, the main
steps of the GAP analysis are described in detail. Guidelines are provided on how to improve the
workplace manufacturing process through certain improvements by applying all 5S elements.
According to the implemented action plan, the main causes of risk occurrence in the GAP analysis
were: human factor and processing technologies. The human factor was characterized by poor
control in the workplace (there is no discipline), poor training and incompetence of employees for
the given tasks. Processing technology involves obsolete machines, which can introduce deviations
of dimensions and tolerances from the prescribed values., U ovom radu, analizirani su GAP analiza i 5S alat na primeru realizacije malogabaritnog transmitera pritiska. GAP analiza, u kombinaciji sa 5S alatom, može kvalitetno ukazuje na kritične tačke u procesu proizvodnje, sklapanja i kontrole gotovog transmitera. Postojeće greške dovode do pojave mogućih rizika u realizaciji proizvodnih procesa, od ulaza repromaterijala do sklapanja gotovog proizvoda. Analiza rizika, omogućava organizaciji da preuzme određene korake u prihvatanju ili smanjenju njegovog uticaja. 5S alat u GAP analizi pomaže da se rizična mesta srede i dovedu u funkcionalno stanje, sa što manje gubitaka (otpada). Zbog eliminacije postojećih grešaka, u radu su detaljno opisani glavni koraci GAP analize. Date su smernice kako da se unapredi proces proizvodnje na radnom mestu kroz određena poboljšanja primenom svih 5S elemenata. Prema sprovedenom akcionom planu konstatovano je da su glavni uzročnici pojave rizika u GAP analizi sledeći: ljudski faktor i tehnologije obrade. Ljudski faktor je okarakterisan slabom kontrolom na radnom mestu (ne postoji disciplina), slabom obukom i nekompetentnošću zaposlenih za propisano radno mesto. Tehnologija obrade podrazumeva tehnološki zastarele mašine i odstupanja mera i tolerancija od propisanih vrednosti",
publisher = "Zrenjanin: University of Novi Sad - 'Mihajlo Pupin' Technical Faculty",
journal = "Journal of Engineering Management and Competitiveness (JEM)",
title = "5S Elements as steps to bridge the gap in transmitter manufacturing process, 5S elementi kao koraci za premošćivanje procepa u procesu prozvodnje transmitera",
volume = "9",
number = "2",
pages = "148-158",
doi = "10.5937/jemc1902148V"
}

Vorkapić, M., Bogetić, S., Tanović, D., Hasan, M. S.,& Kovačević, A.. (2019). 5S Elements as steps to bridge the gap in transmitter manufacturing process. in Journal of Engineering Management and Competitiveness (JEM)
Zrenjanin: University of Novi Sad - 'Mihajlo Pupin' Technical Faculty., 9(2), 148-158.
https://doi.org/10.5937/jemc1902148V

Vorkapić M, Bogetić S, Tanović D, Hasan MS, Kovačević A. 5S Elements as steps to bridge the gap in transmitter manufacturing process. in Journal of Engineering Management and Competitiveness (JEM). 2019;9(2):148-158.
doi:10.5937/jemc1902148V .

Vorkapić, Miloš, Bogetić, Srđan, Tanović, Dragoljub, Hasan, Mohammad Sakib, Kovačević, Aleksandar, "5S Elements as steps to bridge the gap in transmitter manufacturing process" in Journal of Engineering Management and Competitiveness (JEM), 9, no. 2 (2019):148-158,
https://doi.org/10.5937/jemc1902148V . .