TY  - JOUR
AU  - Bošnjak, Srđan
AU  - Petković, Zoran D.
AU  - Đorđević, Miloš
PY  - 2011
UR  - https://machinery.mas.bg.ac.rs/handle/123456789/1246
AB  - U radu su prezentirana tri tehnička rešenja nastala tokom realizacije projekta iz programa tehnološkog razvoja. Dva tehnička rešenja predstavljaju unapređenja postojećih mašina - redizajn dvotočkovnih kolica guseničnog kretača i obrtne platforme rotornih bagera. Njihovom primenom omogućen je pouzdan rad sistema površinske eksploatacije. Treće tehničko rešenje predstavlja nov proizvod - sistem mehanizacije bočnog navoza brodogradilišta rečno - morskih brodova, čije performanse gotovo dvostruko prevazilaze performanse koje se u referentnoj literaturi navode kao granične. Izgradnja brodogradilišta 'Bomex 4M' i realizacija originalnih rešenja sistema za vuču kolica, značajno je proširila izvozne mogućnosti naše zemlje kada je reč o brodogradnji. .
AB  - This paper presents three technical solutions that have emerged during the realization of the project from the technological development program. Two of these solutions are in fact improvements to the existing machines - the redesign of the crawler two wheel bogie and the slewing platform of the bucket wheel excavator. The application of these solutions enabled safe operation of the surface mining system. The third technical solution is a new product: high - performance mechanized side slipway for river, sea and oversea ships, the performances of which exceed almost doubly those listed as limit ones in the referenced literature. The construction of the 'Bomex 4M' shipyard and the realization of the transport system's original design, significantly raised our country's export possibilities when it comes to shipbuilding. .
PB  - Savez inženjera i tehničara Srbije, Beograd
T2  - Tehnika
T1  - Tehnička rešenja kao fundamentalni rezultati projekta iz programa tehnološkog razvoja
T1  - Technical solutions as fundamental results of the project from the technological development program
EP  - 74
IS  - 1
SP  - 67
VL  - 66
UR  - https://hdl.handle.net/21.15107/rcub_machinery_1246
ER  - 

@article{
author = "Bošnjak, Srđan and Petković, Zoran D. and Đorđević, Miloš",
year = "2011",
abstract = "U radu su prezentirana tri tehnička rešenja nastala tokom realizacije projekta iz programa tehnološkog razvoja. Dva tehnička rešenja predstavljaju unapređenja postojećih mašina - redizajn dvotočkovnih kolica guseničnog kretača i obrtne platforme rotornih bagera. Njihovom primenom omogućen je pouzdan rad sistema površinske eksploatacije. Treće tehničko rešenje predstavlja nov proizvod - sistem mehanizacije bočnog navoza brodogradilišta rečno - morskih brodova, čije performanse gotovo dvostruko prevazilaze performanse koje se u referentnoj literaturi navode kao granične. Izgradnja brodogradilišta 'Bomex 4M' i realizacija originalnih rešenja sistema za vuču kolica, značajno je proširila izvozne mogućnosti naše zemlje kada je reč o brodogradnji. ., This paper presents three technical solutions that have emerged during the realization of the project from the technological development program. Two of these solutions are in fact improvements to the existing machines - the redesign of the crawler two wheel bogie and the slewing platform of the bucket wheel excavator. The application of these solutions enabled safe operation of the surface mining system. The third technical solution is a new product: high - performance mechanized side slipway for river, sea and oversea ships, the performances of which exceed almost doubly those listed as limit ones in the referenced literature. The construction of the 'Bomex 4M' shipyard and the realization of the transport system's original design, significantly raised our country's export possibilities when it comes to shipbuilding. .",
publisher = "Savez inženjera i tehničara Srbije, Beograd",
journal = "Tehnika",
title = "Tehnička rešenja kao fundamentalni rezultati projekta iz programa tehnološkog razvoja, Technical solutions as fundamental results of the project from the technological development program",
pages = "74-67",
number = "1",
volume = "66",
url = "https://hdl.handle.net/21.15107/rcub_machinery_1246"
}

Bošnjak, S., Petković, Z. D.,& Đorđević, M.. (2011). Tehnička rešenja kao fundamentalni rezultati projekta iz programa tehnološkog razvoja. in Tehnika
Savez inženjera i tehničara Srbije, Beograd., 66(1), 67-74.
https://hdl.handle.net/21.15107/rcub_machinery_1246

Bošnjak S, Petković ZD, Đorđević M. Tehnička rešenja kao fundamentalni rezultati projekta iz programa tehnološkog razvoja. in Tehnika. 2011;66(1):67-74.
https://hdl.handle.net/21.15107/rcub_machinery_1246 .

Bošnjak, Srđan, Petković, Zoran D., Đorđević, Miloš, "Tehnička rešenja kao fundamentalni rezultati projekta iz programa tehnološkog razvoja" in Tehnika, 66, no. 1 (2011):67-74,
https://hdl.handle.net/21.15107/rcub_machinery_1246 .

TY  - JOUR
AU  - Cović, V.
AU  - Vesković, M.
AU  - Obradović, Aleksandar
PY  - 2011
UR  - https://machinery.mas.bg.ac.rs/handle/123456789/1210
AB  - This paper deals with the instability of steady motions of conservative mechanical systems with cyclic coordinates. The following are applied: Kozlov's generalization of the first Lyapunov's method, as well as Rout's method of ignoration of cyclic coordinates. Having obtained through analysis the Maclaurin's series for the coefficients of the metric tensor, a theorem on instability is formulated which, together with the theorem formulated in Furta (J. Appl. Math. Mech. 50(6):938-944, 1986), contributes to solving the problem of inversion of the Lagrange-Dirichlet theorem for steady motions. The cases in which truncated equations involve the gyroscopic forces are solved, too. The algebraic equations resulting from Kozlov's generalizations of the first Lyapunov's method are formulated in a form including one variable less than was the case in existing literature.
PB  - Springer, Dordrecht
T2  - Meccanica
T1  - On the instability of steady motion
EP  - 863
IS  - 4
SP  - 855
VL  - 46
DO  - 10.1007/s11012-010-9348-2
ER  - 

@article{
author = "Cović, V. and Vesković, M. and Obradović, Aleksandar",
year = "2011",
abstract = "This paper deals with the instability of steady motions of conservative mechanical systems with cyclic coordinates. The following are applied: Kozlov's generalization of the first Lyapunov's method, as well as Rout's method of ignoration of cyclic coordinates. Having obtained through analysis the Maclaurin's series for the coefficients of the metric tensor, a theorem on instability is formulated which, together with the theorem formulated in Furta (J. Appl. Math. Mech. 50(6):938-944, 1986), contributes to solving the problem of inversion of the Lagrange-Dirichlet theorem for steady motions. The cases in which truncated equations involve the gyroscopic forces are solved, too. The algebraic equations resulting from Kozlov's generalizations of the first Lyapunov's method are formulated in a form including one variable less than was the case in existing literature.",
publisher = "Springer, Dordrecht",
journal = "Meccanica",
title = "On the instability of steady motion",
pages = "863-855",
number = "4",
volume = "46",
doi = "10.1007/s11012-010-9348-2"
}

Cović, V., Vesković, M.,& Obradović, A.. (2011). On the instability of steady motion. in Meccanica
Springer, Dordrecht., 46(4), 855-863.
https://doi.org/10.1007/s11012-010-9348-2

Cović V, Vesković M, Obradović A. On the instability of steady motion. in Meccanica. 2011;46(4):855-863.
doi:10.1007/s11012-010-9348-2 .

Cović, V., Vesković, M., Obradović, Aleksandar, "On the instability of steady motion" in Meccanica, 46, no. 4 (2011):855-863,
https://doi.org/10.1007/s11012-010-9348-2 . .

TY  - JOUR
AU  - Ognjanović, Milosav
AU  - Simonović, Aleksandar
AU  - Ristivojević, Mileta
AU  - Lazović, Tatjana
PY  - 2010
UR  - https://machinery.mas.bg.ac.rs/handle/123456789/1060
AB  - Traction shafts and axles of railway vehicles are designed to be safe and reliable in normal service conditions Accidental and unpredictable conditions including bad exploitation (rail tracks, maintenance and extreme long service life) make the probability of shaft and axle fracture realistic. This article contains the experience and analysis of the traction shafts and axles fractures and fracture processes. Research also shows service conditions with results presented in the form of service stress spectrums. Besides normal service conditions, the results also include unpredictable phenomenon such as natural torsion vibrations of the shaft and wheels caused by stick-slip processes at the moment of the set in motion of a full-loaded train or at the moment of braking. These vibrations create an extremely high level of torque which is the main cause of cracks initialization. The next part of the article contains the results of the traction shafts and axles endurance research. The results of testing are transformed using the results of calculation by the FE method and by statistical estimation of the failure probability distribution. The main part refers to the interaction (impact) of service stress probability and failure (endurance) probability. which leads to the traction shaft (axle) reliability definition. Using the established model, locomotive traction shaft reliability is calculated and analyzed. The final part of the article contains suggestions for the traction shafts (axles) failure prevention
PB  - Pergamon-Elsevier Science Ltd, Oxford
T2  - Engineering Failure Analysis
T1  - Research of rail traction shafts and axles fractures towards impact of service conditions and fatigue damage accumulation
EP  - 1571
IS  - 7-8
SP  - 1560
VL  - 17
DO  - 10.1016/j.engfailanal.2010.06.007
ER  - 

@article{
author = "Ognjanović, Milosav and Simonović, Aleksandar and Ristivojević, Mileta and Lazović, Tatjana",
year = "2010",
abstract = "Traction shafts and axles of railway vehicles are designed to be safe and reliable in normal service conditions Accidental and unpredictable conditions including bad exploitation (rail tracks, maintenance and extreme long service life) make the probability of shaft and axle fracture realistic. This article contains the experience and analysis of the traction shafts and axles fractures and fracture processes. Research also shows service conditions with results presented in the form of service stress spectrums. Besides normal service conditions, the results also include unpredictable phenomenon such as natural torsion vibrations of the shaft and wheels caused by stick-slip processes at the moment of the set in motion of a full-loaded train or at the moment of braking. These vibrations create an extremely high level of torque which is the main cause of cracks initialization. The next part of the article contains the results of the traction shafts and axles endurance research. The results of testing are transformed using the results of calculation by the FE method and by statistical estimation of the failure probability distribution. The main part refers to the interaction (impact) of service stress probability and failure (endurance) probability. which leads to the traction shaft (axle) reliability definition. Using the established model, locomotive traction shaft reliability is calculated and analyzed. The final part of the article contains suggestions for the traction shafts (axles) failure prevention",
publisher = "Pergamon-Elsevier Science Ltd, Oxford",
journal = "Engineering Failure Analysis",
title = "Research of rail traction shafts and axles fractures towards impact of service conditions and fatigue damage accumulation",
pages = "1571-1560",
number = "7-8",
volume = "17",
doi = "10.1016/j.engfailanal.2010.06.007"
}

Ognjanović, M., Simonović, A., Ristivojević, M.,& Lazović, T.. (2010). Research of rail traction shafts and axles fractures towards impact of service conditions and fatigue damage accumulation. in Engineering Failure Analysis
Pergamon-Elsevier Science Ltd, Oxford., 17(7-8), 1560-1571.
https://doi.org/10.1016/j.engfailanal.2010.06.007

Ognjanović M, Simonović A, Ristivojević M, Lazović T. Research of rail traction shafts and axles fractures towards impact of service conditions and fatigue damage accumulation. in Engineering Failure Analysis. 2010;17(7-8):1560-1571.
doi:10.1016/j.engfailanal.2010.06.007 .

Ognjanović, Milosav, Simonović, Aleksandar, Ristivojević, Mileta, Lazović, Tatjana, "Research of rail traction shafts and axles fractures towards impact of service conditions and fatigue damage accumulation" in Engineering Failure Analysis, 17, no. 7-8 (2010):1560-1571,
https://doi.org/10.1016/j.engfailanal.2010.06.007 . .

TY  - JOUR
AU  - Zrnić, Nenad
AU  - Bošnjak, Srđan
AU  - Hoffmann, K.
PY  - 2010
UR  - https://machinery.mas.bg.ac.rs/handle/123456789/1108
AB  - This paper gives an analysis of dynamic behaviour of the waterside boom, previously identified as the most important structural part of the mega quayside container cranes (QCC) under moving concentrated mass. The non-dimensional mathematical model used in this paper presents a conceptual substitution of the real system of the mega container crane boom and provides understanding and prediction of its dynamic behaviour under the action of a moving trolley. The paper discusses the procedure for setting up the nondimensional mathematical model of the crane boom as a necessary condition for an estimation of structural and trolley drive parameters, such as the effects of stiffness, mass, spatial position of structural segments as well as trolley velocity and acceleration, on the dynamic values of deflection under the moving mass. The results obtained by the simulation of the trolley motion alongside the QCC boom during container transfer from quay-to-ship are implemented in the parameter sensitivity analysis in order to obtain mutual influences of the dynamic parameters.
PB  - Taylor & Francis Inc, Philadelphia
T2  - Mathematical and Computer Modelling of Dynamical Systems
T1  - Parameter sensitivity analysis of non-dimensional models of quayside container cranes
EP  - 160
IS  - 2
SP  - 145
VL  - 16
DO  - 10.1080/13873951003676534
ER  - 

@article{
author = "Zrnić, Nenad and Bošnjak, Srđan and Hoffmann, K.",
year = "2010",
abstract = "This paper gives an analysis of dynamic behaviour of the waterside boom, previously identified as the most important structural part of the mega quayside container cranes (QCC) under moving concentrated mass. The non-dimensional mathematical model used in this paper presents a conceptual substitution of the real system of the mega container crane boom and provides understanding and prediction of its dynamic behaviour under the action of a moving trolley. The paper discusses the procedure for setting up the nondimensional mathematical model of the crane boom as a necessary condition for an estimation of structural and trolley drive parameters, such as the effects of stiffness, mass, spatial position of structural segments as well as trolley velocity and acceleration, on the dynamic values of deflection under the moving mass. The results obtained by the simulation of the trolley motion alongside the QCC boom during container transfer from quay-to-ship are implemented in the parameter sensitivity analysis in order to obtain mutual influences of the dynamic parameters.",
publisher = "Taylor & Francis Inc, Philadelphia",
journal = "Mathematical and Computer Modelling of Dynamical Systems",
title = "Parameter sensitivity analysis of non-dimensional models of quayside container cranes",
pages = "160-145",
number = "2",
volume = "16",
doi = "10.1080/13873951003676534"
}

Zrnić, N., Bošnjak, S.,& Hoffmann, K.. (2010). Parameter sensitivity analysis of non-dimensional models of quayside container cranes. in Mathematical and Computer Modelling of Dynamical Systems
Taylor & Francis Inc, Philadelphia., 16(2), 145-160.
https://doi.org/10.1080/13873951003676534

Zrnić N, Bošnjak S, Hoffmann K. Parameter sensitivity analysis of non-dimensional models of quayside container cranes. in Mathematical and Computer Modelling of Dynamical Systems. 2010;16(2):145-160.
doi:10.1080/13873951003676534 .

Zrnić, Nenad, Bošnjak, Srđan, Hoffmann, K., "Parameter sensitivity analysis of non-dimensional models of quayside container cranes" in Mathematical and Computer Modelling of Dynamical Systems, 16, no. 2 (2010):145-160,
https://doi.org/10.1080/13873951003676534 . .

TY  - JOUR
AU  - Bošnjak, Srđan
PY  - 2010
UR  - https://machinery.mas.bg.ac.rs/handle/123456789/1094
AB  - Neprekidna eksploatacija u vrlo teškim radnim uslovima dovodi do relativno čestih otkaza podsistema rotornih bagera i pretovarnih mostova za ugalj. Visoko mesto među uzročnicima pomenutih otkaza zauzimaju propusti projektanata - greške u analizi opterećenja, modeliranju i analizi odziva. U radu je izložen originalan postupak identifikacije opterećenja izazvanog otporom kopanja, koji obuhvata sve relevantne konstrukcione parametre, kao i parametre režima rada mašine. Njegova validacija izvršena je merenjima u realnim eksploatacionim uslovima. Osim toga, izložen je i postupak formiranja dinamičkog modela nadgradnje rotornih bagera. On omogućava da se sa dovoljnom tačnošću analizira njen odziv i utvrdi nivo značajnosti parametara pojedinih podsistema. Prezentiran je redizajn obrtne platforme bagera i noseće konstrukcije pretovarnog mosta za ugalj. Rezultati merenja i višegodišnja eksploatacija nedvosmisleno su potvrdili uspešnost primenjenog koncepta redizajna.
AB  - Constant exploitation of heavy duty machines, such as the bucket wheel excavator and bridgetype stacker-reclaimer, under the action of highly pronounced dynamic loads, may lead to the failures of their substructures and subassemblies. Unfortunately, high position among the causes of mentioned failures belongs to the designers omissions - mistakes done on the occasion of load analysis, modeling and response analysis. This paper presents an original procedure of calculating external loads caused by force resisting excavation. Model comprises all relevant structural parameters and parameters of duty cycles. Measurements in the real operating conditions have been done in order to establish the credibility of simulation model. Besides that, this paper discusses procedures for dynamic modeling of bucket wheel excavator superstructure. Developed model enables response analysis, with quite satisfactory accuracy, from the engineering point of view. Redesign of the bucket wheel excavator slewing platform, as well as redesign of the bridge-type stacker-reclaimer structure, is presented. The efficiency of these reconstructions is unquestionably confirmed by failure less service of mentioned machines.
PB  - Institut za istraživanja i projektovanja u privredi, Beograd
T2  - Journal of Applied Engineering Science
T1  - Neki problemi dinamike i čvrstoće mašina visokih performansi
T1  - Some of the problems on dynamics and strength of the high performance machines
EP  - 12
IS  - 1
SP  - 1
VL  - 8
UR  - https://hdl.handle.net/21.15107/rcub_machinery_1094
ER  - 

@article{
author = "Bošnjak, Srđan",
year = "2010",
abstract = "Neprekidna eksploatacija u vrlo teškim radnim uslovima dovodi do relativno čestih otkaza podsistema rotornih bagera i pretovarnih mostova za ugalj. Visoko mesto među uzročnicima pomenutih otkaza zauzimaju propusti projektanata - greške u analizi opterećenja, modeliranju i analizi odziva. U radu je izložen originalan postupak identifikacije opterećenja izazvanog otporom kopanja, koji obuhvata sve relevantne konstrukcione parametre, kao i parametre režima rada mašine. Njegova validacija izvršena je merenjima u realnim eksploatacionim uslovima. Osim toga, izložen je i postupak formiranja dinamičkog modela nadgradnje rotornih bagera. On omogućava da se sa dovoljnom tačnošću analizira njen odziv i utvrdi nivo značajnosti parametara pojedinih podsistema. Prezentiran je redizajn obrtne platforme bagera i noseće konstrukcije pretovarnog mosta za ugalj. Rezultati merenja i višegodišnja eksploatacija nedvosmisleno su potvrdili uspešnost primenjenog koncepta redizajna., Constant exploitation of heavy duty machines, such as the bucket wheel excavator and bridgetype stacker-reclaimer, under the action of highly pronounced dynamic loads, may lead to the failures of their substructures and subassemblies. Unfortunately, high position among the causes of mentioned failures belongs to the designers omissions - mistakes done on the occasion of load analysis, modeling and response analysis. This paper presents an original procedure of calculating external loads caused by force resisting excavation. Model comprises all relevant structural parameters and parameters of duty cycles. Measurements in the real operating conditions have been done in order to establish the credibility of simulation model. Besides that, this paper discusses procedures for dynamic modeling of bucket wheel excavator superstructure. Developed model enables response analysis, with quite satisfactory accuracy, from the engineering point of view. Redesign of the bucket wheel excavator slewing platform, as well as redesign of the bridge-type stacker-reclaimer structure, is presented. The efficiency of these reconstructions is unquestionably confirmed by failure less service of mentioned machines.",
publisher = "Institut za istraživanja i projektovanja u privredi, Beograd",
journal = "Journal of Applied Engineering Science",
title = "Neki problemi dinamike i čvrstoće mašina visokih performansi, Some of the problems on dynamics and strength of the high performance machines",
pages = "12-1",
number = "1",
volume = "8",
url = "https://hdl.handle.net/21.15107/rcub_machinery_1094"
}

Bošnjak, S.. (2010). Neki problemi dinamike i čvrstoće mašina visokih performansi. in Journal of Applied Engineering Science
Institut za istraživanja i projektovanja u privredi, Beograd., 8(1), 1-12.
https://hdl.handle.net/21.15107/rcub_machinery_1094

Bošnjak S. Neki problemi dinamike i čvrstoće mašina visokih performansi. in Journal of Applied Engineering Science. 2010;8(1):1-12.
https://hdl.handle.net/21.15107/rcub_machinery_1094 .

Bošnjak, Srđan, "Neki problemi dinamike i čvrstoće mašina visokih performansi" in Journal of Applied Engineering Science, 8, no. 1 (2010):1-12,
https://hdl.handle.net/21.15107/rcub_machinery_1094 .

TY  - JOUR
AU  - Obradović, Aleksandar
AU  - Cović, V.
AU  - Vesković, M.
AU  - Dražić, Milan
PY  - 2010
UR  - https://machinery.mas.bg.ac.rs/handle/123456789/1110
AB  - The brachistochrone problem of the rheonomic mechanical system whose motion is subject to nonholonomic constraints is solved with nonlinear differential equations of motion. Apart from control forces, the system is influenced by the action of other known potential and nonpotential forces as well. The problem of optimal control is solved by applying Pontryagin's Maximum Principle and the singular optimal control theory. This procedure results in the two-point boundary value problem for the system of ordinary nonlinear differential equations of the first order, with a corresponding number of initial and end conditions. This paper determines the control forces that are realized by imposing on the system a corresponding number of independent ideal holonomic constraints, without the action of active control forces. These constraints must be in accordance with the previously determined brachistochronic motion. The method is illustrated with a single complex example that represents the first known concrete demonstration of brachistochronic motion of the nonholonomic rheonomic mechanical system.
PB  - Springer Wien, Wien
T2  - Acta Mechanica
T1  - Brachistochronic motion of a nonholonomic rheonomic mechanical system
EP  - 304
IS  - 3-4
SP  - 291
VL  - 214
DO  - 10.1007/s00707-010-0295-8
ER  - 

@article{
author = "Obradović, Aleksandar and Cović, V. and Vesković, M. and Dražić, Milan",
year = "2010",
abstract = "The brachistochrone problem of the rheonomic mechanical system whose motion is subject to nonholonomic constraints is solved with nonlinear differential equations of motion. Apart from control forces, the system is influenced by the action of other known potential and nonpotential forces as well. The problem of optimal control is solved by applying Pontryagin's Maximum Principle and the singular optimal control theory. This procedure results in the two-point boundary value problem for the system of ordinary nonlinear differential equations of the first order, with a corresponding number of initial and end conditions. This paper determines the control forces that are realized by imposing on the system a corresponding number of independent ideal holonomic constraints, without the action of active control forces. These constraints must be in accordance with the previously determined brachistochronic motion. The method is illustrated with a single complex example that represents the first known concrete demonstration of brachistochronic motion of the nonholonomic rheonomic mechanical system.",
publisher = "Springer Wien, Wien",
journal = "Acta Mechanica",
title = "Brachistochronic motion of a nonholonomic rheonomic mechanical system",
pages = "304-291",
number = "3-4",
volume = "214",
doi = "10.1007/s00707-010-0295-8"
}

Obradović, A., Cović, V., Vesković, M.,& Dražić, M.. (2010). Brachistochronic motion of a nonholonomic rheonomic mechanical system. in Acta Mechanica
Springer Wien, Wien., 214(3-4), 291-304.
https://doi.org/10.1007/s00707-010-0295-8

Obradović A, Cović V, Vesković M, Dražić M. Brachistochronic motion of a nonholonomic rheonomic mechanical system. in Acta Mechanica. 2010;214(3-4):291-304.
doi:10.1007/s00707-010-0295-8 .

Obradović, Aleksandar, Cović, V., Vesković, M., Dražić, Milan, "Brachistochronic motion of a nonholonomic rheonomic mechanical system" in Acta Mechanica, 214, no. 3-4 (2010):291-304,
https://doi.org/10.1007/s00707-010-0295-8 . .

TY  - JOUR
AU  - Bošnjak, Srđan
AU  - Petković, Zoran D.
AU  - Zrnić, Nenad
AU  - Pantelić, Milorad P.
AU  - Obradović, Aleksandar
PY  - 2010
UR  - https://machinery.mas.bg.ac.rs/handle/123456789/1111
AB  - This paper discusses the cause of the failure in the vital part of the crawler travel gear of the bucket wheel excavator (BWE) - two-wheel bogie (TWB). The results of the finite element analysis (FEA) point out that the main reason of the TWB failure is its insufficient strength under lateral forces acting during curve travel. The weak points in the TWB structure are removed by suitable redesign while keeping in mind all restrictions ensuing from installation conditions and functionality of the existing crawler travel gear. In addition to the numerical analysis (FEA), a parallel experimental analysis of the original as well as the redesigned TWB is conducted on a test board especially designed for this purpose. The experimental results have confirmed the considerably improved response on lateral loads of the redesigned TWB. The exploitation of the redesigned TWB with no failures has confirmed the validity of the reconstruction design.
PB  - Pergamon-Elsevier Science Ltd, Oxford
T2  - Engineering Failure Analysis
T1  - Failure analysis and redesign of the bucket wheel excavator two-wheel bogie
EP  - 485
IS  - 2
SP  - 473
VL  - 17
DO  - 10.1016/j.engfailanal.2009.09.007
ER  - 

@article{
author = "Bošnjak, Srđan and Petković, Zoran D. and Zrnić, Nenad and Pantelić, Milorad P. and Obradović, Aleksandar",
year = "2010",
abstract = "This paper discusses the cause of the failure in the vital part of the crawler travel gear of the bucket wheel excavator (BWE) - two-wheel bogie (TWB). The results of the finite element analysis (FEA) point out that the main reason of the TWB failure is its insufficient strength under lateral forces acting during curve travel. The weak points in the TWB structure are removed by suitable redesign while keeping in mind all restrictions ensuing from installation conditions and functionality of the existing crawler travel gear. In addition to the numerical analysis (FEA), a parallel experimental analysis of the original as well as the redesigned TWB is conducted on a test board especially designed for this purpose. The experimental results have confirmed the considerably improved response on lateral loads of the redesigned TWB. The exploitation of the redesigned TWB with no failures has confirmed the validity of the reconstruction design.",
publisher = "Pergamon-Elsevier Science Ltd, Oxford",
journal = "Engineering Failure Analysis",
title = "Failure analysis and redesign of the bucket wheel excavator two-wheel bogie",
pages = "485-473",
number = "2",
volume = "17",
doi = "10.1016/j.engfailanal.2009.09.007"
}

Bošnjak, S., Petković, Z. D., Zrnić, N., Pantelić, M. P.,& Obradović, A.. (2010). Failure analysis and redesign of the bucket wheel excavator two-wheel bogie. in Engineering Failure Analysis
Pergamon-Elsevier Science Ltd, Oxford., 17(2), 473-485.
https://doi.org/10.1016/j.engfailanal.2009.09.007

Bošnjak S, Petković ZD, Zrnić N, Pantelić MP, Obradović A. Failure analysis and redesign of the bucket wheel excavator two-wheel bogie. in Engineering Failure Analysis. 2010;17(2):473-485.
doi:10.1016/j.engfailanal.2009.09.007 .

Bošnjak, Srđan, Petković, Zoran D., Zrnić, Nenad, Pantelić, Milorad P., Obradović, Aleksandar, "Failure analysis and redesign of the bucket wheel excavator two-wheel bogie" in Engineering Failure Analysis, 17, no. 2 (2010):473-485,
https://doi.org/10.1016/j.engfailanal.2009.09.007 . .

TY  - JOUR
AU  - Cović, V.
AU  - Vesković, M.
AU  - Djurić, D.
AU  - Obradović, Aleksandar
PY  - 2010
UR  - https://machinery.mas.bg.ac.rs/handle/123456789/1076
AB  - Lyapunov's first method, extended by V. V. Kozlov to nonlinear mechanical systems, is applied to the study of the instability of the position of equilibrium of a mechanical system moving in the field of conservative and dissipative forces. The motion of the system is limited by ideal nonlinear nonholonomic constraints. Five cases determined by the relationship between the degree of the first nontrivial polynomials in Maclaurin's series for the potential energy and the functions that can be generated from the equations of nonlinear nonholonomic constraints are analyzed. In the three cases, the theorem on the instability of the position of equilibrium of nonholonomic systems with linear homogeneous constraints (V. V. Kozlov (1986)) is generalized to the case of nonlinear nonhomogeneous constraints. In the other two cases, new theorems are set extending the result from V. V. Kozlov (1994) to nonholonomic systems with nonlinear constraints.
PB  - SHANGHAI UNIV, SHANGHAI
T2  - Applied Mathematics and Mechanics-English Edition
T1  - On the stability of equilibria of nonholonomic systems with nonlinear constraints
EP  - 760
IS  - 6
SP  - 751
VL  - 31
DO  - 10.1007/s10483-010-1309-7
ER  - 

@article{
author = "Cović, V. and Vesković, M. and Djurić, D. and Obradović, Aleksandar",
year = "2010",
abstract = "Lyapunov's first method, extended by V. V. Kozlov to nonlinear mechanical systems, is applied to the study of the instability of the position of equilibrium of a mechanical system moving in the field of conservative and dissipative forces. The motion of the system is limited by ideal nonlinear nonholonomic constraints. Five cases determined by the relationship between the degree of the first nontrivial polynomials in Maclaurin's series for the potential energy and the functions that can be generated from the equations of nonlinear nonholonomic constraints are analyzed. In the three cases, the theorem on the instability of the position of equilibrium of nonholonomic systems with linear homogeneous constraints (V. V. Kozlov (1986)) is generalized to the case of nonlinear nonhomogeneous constraints. In the other two cases, new theorems are set extending the result from V. V. Kozlov (1994) to nonholonomic systems with nonlinear constraints.",
publisher = "SHANGHAI UNIV, SHANGHAI",
journal = "Applied Mathematics and Mechanics-English Edition",
title = "On the stability of equilibria of nonholonomic systems with nonlinear constraints",
pages = "760-751",
number = "6",
volume = "31",
doi = "10.1007/s10483-010-1309-7"
}

Cović, V., Vesković, M., Djurić, D.,& Obradović, A.. (2010). On the stability of equilibria of nonholonomic systems with nonlinear constraints. in Applied Mathematics and Mechanics-English Edition
SHANGHAI UNIV, SHANGHAI., 31(6), 751-760.
https://doi.org/10.1007/s10483-010-1309-7

Cović V, Vesković M, Djurić D, Obradović A. On the stability of equilibria of nonholonomic systems with nonlinear constraints. in Applied Mathematics and Mechanics-English Edition. 2010;31(6):751-760.
doi:10.1007/s10483-010-1309-7 .

Cović, V., Vesković, M., Djurić, D., Obradović, Aleksandar, "On the stability of equilibria of nonholonomic systems with nonlinear constraints" in Applied Mathematics and Mechanics-English Edition, 31, no. 6 (2010):751-760,
https://doi.org/10.1007/s10483-010-1309-7 . .

TY  - JOUR
AU  - Cović, V.
AU  - Vesković, M.
AU  - Obradović, Aleksandar
PY  - 2010
UR  - https://machinery.mas.bg.ac.rs/handle/123456789/1071
AB  - The first Lyapunov method, extended by V. Kozlov to nonlinear mechanical systems, is applied to the study of the instability of the equilibrium position of a mechanical system moving in the field of potential and dissipative forces. The motion of the system is subject to the action of the ideal linear nonholonomic nonhomogeneous constraints. Five theorems on the instability of the equilibrium position of the above mentioned system are formulated. The theorem formulated in [V. V. Kozlov, On the asymptotic motions of systems with dissipation, J. Appl. Math. Mech. 58 (5) (1994) 787-792], which refers to the instability of the equilibrium position of the holonomic scleronomic mechanical system in the field of potential and dissipative forces, is generalized to the case of nonholonomic systems with linear nonhomogeneous constraints. In other theorems the algebraic criteria of the Kozlov type are transformed into a group of equations required only to have real solutions. The existence of such solutions enables the fulfillment of all conditions related to the initial algebraic criteria. Lastly, a theorem on instability has also been formulated in the case where the matrix of the dissipative function coefficients is singular in the equilibrium position. The results are illustrated by an example.
PB  - Pergamon-Elsevier Science Ltd, Oxford
T2  - Mathematical and Computer Modelling
T1  - On the instability of equilibrium of nonholonomic systems with nonhomogeneous constraints
EP  - 1106
IS  - 9-10
SP  - 1097
VL  - 51
DO  - 10.1016/j.mcm.2009.12.017
ER  - 

@article{
author = "Cović, V. and Vesković, M. and Obradović, Aleksandar",
year = "2010",
abstract = "The first Lyapunov method, extended by V. Kozlov to nonlinear mechanical systems, is applied to the study of the instability of the equilibrium position of a mechanical system moving in the field of potential and dissipative forces. The motion of the system is subject to the action of the ideal linear nonholonomic nonhomogeneous constraints. Five theorems on the instability of the equilibrium position of the above mentioned system are formulated. The theorem formulated in [V. V. Kozlov, On the asymptotic motions of systems with dissipation, J. Appl. Math. Mech. 58 (5) (1994) 787-792], which refers to the instability of the equilibrium position of the holonomic scleronomic mechanical system in the field of potential and dissipative forces, is generalized to the case of nonholonomic systems with linear nonhomogeneous constraints. In other theorems the algebraic criteria of the Kozlov type are transformed into a group of equations required only to have real solutions. The existence of such solutions enables the fulfillment of all conditions related to the initial algebraic criteria. Lastly, a theorem on instability has also been formulated in the case where the matrix of the dissipative function coefficients is singular in the equilibrium position. The results are illustrated by an example.",
publisher = "Pergamon-Elsevier Science Ltd, Oxford",
journal = "Mathematical and Computer Modelling",
title = "On the instability of equilibrium of nonholonomic systems with nonhomogeneous constraints",
pages = "1106-1097",
number = "9-10",
volume = "51",
doi = "10.1016/j.mcm.2009.12.017"
}

Cović, V., Vesković, M.,& Obradović, A.. (2010). On the instability of equilibrium of nonholonomic systems with nonhomogeneous constraints. in Mathematical and Computer Modelling
Pergamon-Elsevier Science Ltd, Oxford., 51(9-10), 1097-1106.
https://doi.org/10.1016/j.mcm.2009.12.017

Cović V, Vesković M, Obradović A. On the instability of equilibrium of nonholonomic systems with nonhomogeneous constraints. in Mathematical and Computer Modelling. 2010;51(9-10):1097-1106.
doi:10.1016/j.mcm.2009.12.017 .

Cović, V., Vesković, M., Obradović, Aleksandar, "On the instability of equilibrium of nonholonomic systems with nonhomogeneous constraints" in Mathematical and Computer Modelling, 51, no. 9-10 (2010):1097-1106,
https://doi.org/10.1016/j.mcm.2009.12.017 . .

TY  - JOUR
AU  - Međo, Bojan
AU  - Rakin, Marko
AU  - Gubeljak, Nenad
AU  - Sedmak, Aleksandar
PY  - 2009
UR  - https://machinery.mas.bg.ac.rs/handle/123456789/887
AB  - Ductile fracture process includes three stages: void nucleation, their growth and coalescence. The voids nucleate due to the fracture or separation of non-metallic inclusions and secondary-phase particles from the material matrix. Micromechanical models based on the Gurson plastic flow criterion are often used for analysis of ductile fracture. They consider the material as a porous medium in which the effect of voids on the stress-strain state and plastic flow cannot be neglected. Another important property of the Gurson criterion is that the hydrostatic stress component influences the plastic flow of the material.
PB  - Trans Tech Publications Ltd
T2  - Key Engineering Materials
T1  - Application of Complete Gurson Model for prediction of ductile fracture in welded steel joints
EP  - 20
SP  - 13
VL  - 399
UR  - https://hdl.handle.net/21.15107/rcub_technorep_1364
ER  - 

@article{
author = "Međo, Bojan and Rakin, Marko and Gubeljak, Nenad and Sedmak, Aleksandar",
year = "2009",
abstract = "Ductile fracture process includes three stages: void nucleation, their growth and coalescence. The voids nucleate due to the fracture or separation of non-metallic inclusions and secondary-phase particles from the material matrix. Micromechanical models based on the Gurson plastic flow criterion are often used for analysis of ductile fracture. They consider the material as a porous medium in which the effect of voids on the stress-strain state and plastic flow cannot be neglected. Another important property of the Gurson criterion is that the hydrostatic stress component influences the plastic flow of the material.",
publisher = "Trans Tech Publications Ltd",
journal = "Key Engineering Materials",
title = "Application of Complete Gurson Model for prediction of ductile fracture in welded steel joints",
pages = "20-13",
volume = "399",
url = "https://hdl.handle.net/21.15107/rcub_technorep_1364"
}

Međo, B., Rakin, M., Gubeljak, N.,& Sedmak, A.. (2009). Application of Complete Gurson Model for prediction of ductile fracture in welded steel joints. in Key Engineering Materials
Trans Tech Publications Ltd., 399, 13-20.
https://hdl.handle.net/21.15107/rcub_technorep_1364

Međo B, Rakin M, Gubeljak N, Sedmak A. Application of Complete Gurson Model for prediction of ductile fracture in welded steel joints. in Key Engineering Materials. 2009;399:13-20.
https://hdl.handle.net/21.15107/rcub_technorep_1364 .

Međo, Bojan, Rakin, Marko, Gubeljak, Nenad, Sedmak, Aleksandar, "Application of Complete Gurson Model for prediction of ductile fracture in welded steel joints" in Key Engineering Materials, 399 (2009):13-20,
https://hdl.handle.net/21.15107/rcub_technorep_1364 .

TY  - JOUR
AU  - Bošnjak, Srđan
AU  - Zrnić, Nenad
AU  - Dragović, Branislav
PY  - 2009
UR  - https://machinery.mas.bg.ac.rs/handle/123456789/885
AB  - This paper deals with the possibility of aerodynamic instability occurrence in the mobile elevating work platform (MEWP) structure. The vibrations of the structure excited by the von Karman street and the movement induced vibrations (galloping phenomenon) are analyzed Based on the results obtained using a model of the real MEWP structure, it is concluded that aerodynamic instability may occur even within the range of permitted operating velocities. Furthermore, this paper shows the possibility of suppressing undesirable dynamic effects by applying concepts of active (intelligent) structures.
T2  - Strojniski Vestnik/Journal of Mechanical Engineering
T1  - Dynamic Response of Mobile Elevating Work Platform under Wind Excitation
EP  - 113
IS  - 2
SP  - 104
VL  - 55
UR  - https://hdl.handle.net/21.15107/rcub_machinery_885
ER  - 

@article{
author = "Bošnjak, Srđan and Zrnić, Nenad and Dragović, Branislav",
year = "2009",
abstract = "This paper deals with the possibility of aerodynamic instability occurrence in the mobile elevating work platform (MEWP) structure. The vibrations of the structure excited by the von Karman street and the movement induced vibrations (galloping phenomenon) are analyzed Based on the results obtained using a model of the real MEWP structure, it is concluded that aerodynamic instability may occur even within the range of permitted operating velocities. Furthermore, this paper shows the possibility of suppressing undesirable dynamic effects by applying concepts of active (intelligent) structures.",
journal = "Strojniski Vestnik/Journal of Mechanical Engineering",
title = "Dynamic Response of Mobile Elevating Work Platform under Wind Excitation",
pages = "113-104",
number = "2",
volume = "55",
url = "https://hdl.handle.net/21.15107/rcub_machinery_885"
}

Bošnjak, S., Zrnić, N.,& Dragović, B.. (2009). Dynamic Response of Mobile Elevating Work Platform under Wind Excitation. in Strojniski Vestnik/Journal of Mechanical Engineering, 55(2), 104-113.
https://hdl.handle.net/21.15107/rcub_machinery_885

Bošnjak S, Zrnić N, Dragović B. Dynamic Response of Mobile Elevating Work Platform under Wind Excitation. in Strojniski Vestnik/Journal of Mechanical Engineering. 2009;55(2):104-113.
https://hdl.handle.net/21.15107/rcub_machinery_885 .

Bošnjak, Srđan, Zrnić, Nenad, Dragović, Branislav, "Dynamic Response of Mobile Elevating Work Platform under Wind Excitation" in Strojniski Vestnik/Journal of Mechanical Engineering, 55, no. 2 (2009):104-113,
https://hdl.handle.net/21.15107/rcub_machinery_885 .

TY  - JOUR
AU  - Bošnjak, Srđan
AU  - Zrnić, Nenad
AU  - Simonović, Aleksandar
AU  - Momčilović, Dejan B.
PY  - 2009
UR  - https://machinery.mas.bg.ac.rs/handle/123456789/954
AB  - This paper describes the failure analysis results of the bucket wheel excavator (BWE) portal tie-rod support. The results of finite elements analysis (FEA) point out the occurrence of pronounced stress concentration, whereby multiple stresses in the failure zone exceed the yield stress of the basic material. Experimental investigation on fracture surfaces by scanning electron microscope (SEM) and light microscope (LM) revealed the existence of porosities and inclusions in the weld metal. Moreover, various types of fracture (fatigue, transition, brittle) and their uneven fraction observed on fracture surfaces are induced by structural characteristics of the base metal, welding technology and the construction itself. Based on the presented results it is conclusive that the failure of the support was the consequence of superposition of the negative effects caused by inadequate shaping and dimensioning of the support assembly for given load conditions, as well as influences of mentioned defects of the metal weld structure.
PB  - Pergamon-Elsevier Science Ltd, Oxford
T2  - Engineering Failure Analysis
T1  - Failure analysis of the end eye connection of the bucket wheel excavator portal tie-rod support
EP  - 750
IS  - 3
SP  - 740
VL  - 16
DO  - 10.1016/j.engfailanal.2008.06.006
ER  - 

@article{
author = "Bošnjak, Srđan and Zrnić, Nenad and Simonović, Aleksandar and Momčilović, Dejan B.",
year = "2009",
abstract = "This paper describes the failure analysis results of the bucket wheel excavator (BWE) portal tie-rod support. The results of finite elements analysis (FEA) point out the occurrence of pronounced stress concentration, whereby multiple stresses in the failure zone exceed the yield stress of the basic material. Experimental investigation on fracture surfaces by scanning electron microscope (SEM) and light microscope (LM) revealed the existence of porosities and inclusions in the weld metal. Moreover, various types of fracture (fatigue, transition, brittle) and their uneven fraction observed on fracture surfaces are induced by structural characteristics of the base metal, welding technology and the construction itself. Based on the presented results it is conclusive that the failure of the support was the consequence of superposition of the negative effects caused by inadequate shaping and dimensioning of the support assembly for given load conditions, as well as influences of mentioned defects of the metal weld structure.",
publisher = "Pergamon-Elsevier Science Ltd, Oxford",
journal = "Engineering Failure Analysis",
title = "Failure analysis of the end eye connection of the bucket wheel excavator portal tie-rod support",
pages = "750-740",
number = "3",
volume = "16",
doi = "10.1016/j.engfailanal.2008.06.006"
}

Bošnjak, S., Zrnić, N., Simonović, A.,& Momčilović, D. B.. (2009). Failure analysis of the end eye connection of the bucket wheel excavator portal tie-rod support. in Engineering Failure Analysis
Pergamon-Elsevier Science Ltd, Oxford., 16(3), 740-750.
https://doi.org/10.1016/j.engfailanal.2008.06.006

Bošnjak S, Zrnić N, Simonović A, Momčilović DB. Failure analysis of the end eye connection of the bucket wheel excavator portal tie-rod support. in Engineering Failure Analysis. 2009;16(3):740-750.
doi:10.1016/j.engfailanal.2008.06.006 .

Bošnjak, Srđan, Zrnić, Nenad, Simonović, Aleksandar, Momčilović, Dejan B., "Failure analysis of the end eye connection of the bucket wheel excavator portal tie-rod support" in Engineering Failure Analysis, 16, no. 3 (2009):740-750,
https://doi.org/10.1016/j.engfailanal.2008.06.006 . .

TY  - CONF
AU  - Gašić, Vlada
AU  - Zrnić, Nenad
AU  - Obradović, Aleksandar
AU  - Milovančević, Milorad
PY  - 2009
UR  - https://machinery.mas.bg.ac.rs/handle/123456789/4030
PB  - Univerzitet u Beogradu, Mašinski fakultet
C3  - Proceedings of the 19th International Conferece on Material Handling, Constructions and Logistics - MHCL’09, Faculty of Mechanical Engineering Belgrade,  Belgrade, 2009.
T1  - Revisiting the Use of Finite Element Packages for Moving Load Problem at Bridge Cranes
EP  - 74
SP  - 71
UR  - https://hdl.handle.net/21.15107/rcub_machinery_4030
ER  - 

@conference{
author = "Gašić, Vlada and Zrnić, Nenad and Obradović, Aleksandar and Milovančević, Milorad",
year = "2009",
publisher = "Univerzitet u Beogradu, Mašinski fakultet",
journal = "Proceedings of the 19th International Conferece on Material Handling, Constructions and Logistics - MHCL’09, Faculty of Mechanical Engineering Belgrade,  Belgrade, 2009.",
title = "Revisiting the Use of Finite Element Packages for Moving Load Problem at Bridge Cranes",
pages = "74-71",
url = "https://hdl.handle.net/21.15107/rcub_machinery_4030"
}

Gašić, V., Zrnić, N., Obradović, A.,& Milovančević, M.. (2009). Revisiting the Use of Finite Element Packages for Moving Load Problem at Bridge Cranes. in Proceedings of the 19th International Conferece on Material Handling, Constructions and Logistics - MHCL’09, Faculty of Mechanical Engineering Belgrade,  Belgrade, 2009.
Univerzitet u Beogradu, Mašinski fakultet., 71-74.
https://hdl.handle.net/21.15107/rcub_machinery_4030

Gašić V, Zrnić N, Obradović A, Milovančević M. Revisiting the Use of Finite Element Packages for Moving Load Problem at Bridge Cranes. in Proceedings of the 19th International Conferece on Material Handling, Constructions and Logistics - MHCL’09, Faculty of Mechanical Engineering Belgrade,  Belgrade, 2009.. 2009;:71-74.
https://hdl.handle.net/21.15107/rcub_machinery_4030 .

Gašić, Vlada, Zrnić, Nenad, Obradović, Aleksandar, Milovančević, Milorad, "Revisiting the Use of Finite Element Packages for Moving Load Problem at Bridge Cranes" in Proceedings of the 19th International Conferece on Material Handling, Constructions and Logistics - MHCL’09, Faculty of Mechanical Engineering Belgrade,  Belgrade, 2009. (2009):71-74,
https://hdl.handle.net/21.15107/rcub_machinery_4030 .

TY  - CONF
AU  - Arsić, Miodrag
AU  - Veljović, A.
AU  - Rakin, Marko
AU  - Radaković, Zoran
AU  - Mladenović, M.
PY  - 2009
UR  - https://machinery.mas.bg.ac.rs/handle/123456789/5473
AB  - Structural reliability and integrity include analysis of state, diagnostics of structural behaviour and compliance, life assessment and revitalization of structures. Aside to assessment based on flaws detected by non-destructive methods, these disciplines also include stress state analysis. Detailed distributions of displacement, deformation and stress are acquired determining “weak” locations. This approach is important for structures exposed to complex dynamical loads as bucket wheel excavators.
Fatigue research deals with welded joints as critical locations in welded structures. Under variable loads, stress concentration effects are pronounced not only by geometry and shape, but also by flaws. Flaws originate in design and construction, or in the technology, inspection and testing. Multiple parameters become critical compared to base material. Reliability is observed with more complexity as the probability of proper functionality of responsible welded joints in prescribed working conditions and operating life. The relationship between probability of failure and the degree of overlapping and shape of critical and working stress spectra are clarified and enable reliability determination in responsible welded joints.
PB  - University of Belgrade, Faculty of Mechanical Engineering
C3  - Proc. XIX International Conference on Material Handling, Constructions and Logistics, MHCL’09, Faculty of Mechanical Engineering, University of Belgrade
T1  - Reliability of critical welded joints in responsible support structures of bucket wheel excavator
EP  - 138
SP  - 133
UR  - https://hdl.handle.net/21.15107/rcub_machinery_5473
ER  - 

@conference{
author = "Arsić, Miodrag and Veljović, A. and Rakin, Marko and Radaković, Zoran and Mladenović, M.",
year = "2009",
abstract = "Structural reliability and integrity include analysis of state, diagnostics of structural behaviour and compliance, life assessment and revitalization of structures. Aside to assessment based on flaws detected by non-destructive methods, these disciplines also include stress state analysis. Detailed distributions of displacement, deformation and stress are acquired determining “weak” locations. This approach is important for structures exposed to complex dynamical loads as bucket wheel excavators.
Fatigue research deals with welded joints as critical locations in welded structures. Under variable loads, stress concentration effects are pronounced not only by geometry and shape, but also by flaws. Flaws originate in design and construction, or in the technology, inspection and testing. Multiple parameters become critical compared to base material. Reliability is observed with more complexity as the probability of proper functionality of responsible welded joints in prescribed working conditions and operating life. The relationship between probability of failure and the degree of overlapping and shape of critical and working stress spectra are clarified and enable reliability determination in responsible welded joints.",
publisher = "University of Belgrade, Faculty of Mechanical Engineering",
journal = "Proc. XIX International Conference on Material Handling, Constructions and Logistics, MHCL’09, Faculty of Mechanical Engineering, University of Belgrade",
title = "Reliability of critical welded joints in responsible support structures of bucket wheel excavator",
pages = "138-133",
url = "https://hdl.handle.net/21.15107/rcub_machinery_5473"
}

Arsić, M., Veljović, A., Rakin, M., Radaković, Z.,& Mladenović, M.. (2009). Reliability of critical welded joints in responsible support structures of bucket wheel excavator. in Proc. XIX International Conference on Material Handling, Constructions and Logistics, MHCL’09, Faculty of Mechanical Engineering, University of Belgrade
University of Belgrade, Faculty of Mechanical Engineering., 133-138.
https://hdl.handle.net/21.15107/rcub_machinery_5473

Arsić M, Veljović A, Rakin M, Radaković Z, Mladenović M. Reliability of critical welded joints in responsible support structures of bucket wheel excavator. in Proc. XIX International Conference on Material Handling, Constructions and Logistics, MHCL’09, Faculty of Mechanical Engineering, University of Belgrade. 2009;:133-138.
https://hdl.handle.net/21.15107/rcub_machinery_5473 .

Arsić, Miodrag, Veljović, A., Rakin, Marko, Radaković, Zoran, Mladenović, M., "Reliability of critical welded joints in responsible support structures of bucket wheel excavator" in Proc. XIX International Conference on Material Handling, Constructions and Logistics, MHCL’09, Faculty of Mechanical Engineering, University of Belgrade (2009):133-138,
https://hdl.handle.net/21.15107/rcub_machinery_5473 .

TY  - JOUR
AU  - Zrnić, Nenad
AU  - Hoffmann, K.
AU  - Bošnjak, Srđan
PY  - 2009
UR  - https://machinery.mas.bg.ac.rs/handle/123456789/947
AB  - This article deals with the analysis of trolley impact on the dynamic behaviour of the flexible structure of the mega quayside container crane (QCC) boom, identified as the most relevant structural part. It develops a modelling method for the dynamic response of the large flexible structure of the QCC boom under a moving trolley. By using FEM the original structure of the whole crane structure is reduced to an equivalent model of the boom. The boom is in this way modelled as a system with distributed parameters, comprising reduced stiffnesses and lumped masses from other parts of the upper structure. The article looks at the moving mass approach to achieve the desired performance of the QCC. Differential equations of the mathematical model are obtained by using Lagrange's equations and the assumed mode method. The continuum is discretized by a finite number of admissible functions. Deterministic simulation gives the dynamic response of the boom for quay-to-ship container transfer. Results are obtained for the boom deflection and bending moment values, as well as for the dynamic amplification factor of deflection.
PB  - Taylor & Francis Inc, Philadelphia
T2  - Mathematical and Computer Modelling of Dynamical Systems
T1  - Modelling of dynamic interaction between structure and trolley for mega container cranes
EP  - 311
IS  - 3
SP  - 295
VL  - 15
DO  - 10.1080/13873950902927675
ER  - 

@article{
author = "Zrnić, Nenad and Hoffmann, K. and Bošnjak, Srđan",
year = "2009",
abstract = "This article deals with the analysis of trolley impact on the dynamic behaviour of the flexible structure of the mega quayside container crane (QCC) boom, identified as the most relevant structural part. It develops a modelling method for the dynamic response of the large flexible structure of the QCC boom under a moving trolley. By using FEM the original structure of the whole crane structure is reduced to an equivalent model of the boom. The boom is in this way modelled as a system with distributed parameters, comprising reduced stiffnesses and lumped masses from other parts of the upper structure. The article looks at the moving mass approach to achieve the desired performance of the QCC. Differential equations of the mathematical model are obtained by using Lagrange's equations and the assumed mode method. The continuum is discretized by a finite number of admissible functions. Deterministic simulation gives the dynamic response of the boom for quay-to-ship container transfer. Results are obtained for the boom deflection and bending moment values, as well as for the dynamic amplification factor of deflection.",
publisher = "Taylor & Francis Inc, Philadelphia",
journal = "Mathematical and Computer Modelling of Dynamical Systems",
title = "Modelling of dynamic interaction between structure and trolley for mega container cranes",
pages = "311-295",
number = "3",
volume = "15",
doi = "10.1080/13873950902927675"
}

Zrnić, N., Hoffmann, K.,& Bošnjak, S.. (2009). Modelling of dynamic interaction between structure and trolley for mega container cranes. in Mathematical and Computer Modelling of Dynamical Systems
Taylor & Francis Inc, Philadelphia., 15(3), 295-311.
https://doi.org/10.1080/13873950902927675

Zrnić N, Hoffmann K, Bošnjak S. Modelling of dynamic interaction between structure and trolley for mega container cranes. in Mathematical and Computer Modelling of Dynamical Systems. 2009;15(3):295-311.
doi:10.1080/13873950902927675 .

Zrnić, Nenad, Hoffmann, K., Bošnjak, Srđan, "Modelling of dynamic interaction between structure and trolley for mega container cranes" in Mathematical and Computer Modelling of Dynamical Systems, 15, no. 3 (2009):295-311,
https://doi.org/10.1080/13873950902927675 . .

TY  - JOUR
AU  - Bošnjak, Srđan
AU  - Petković, Zoran D.
AU  - Zrnić, Nenad
AU  - Simić, Goran
AU  - Simonović, Aleksandar
PY  - 2009
UR  - https://machinery.mas.bg.ac.rs/handle/123456789/978
AB  - This paper discusses the results of the investigation of occurrence of cracks in the structure of bucket wheel excavator (BWE) slewing platform, the repair procedure and the reconstruction of the slewing platform. The results of the finite elements analysis (FEA) point out the pronounced stress concentration in the zones of crack occurrence. The values of calculated stresses in the said zones exceed the yield stress of the material. The design solution for the slewing platform reconstruction is chosen based on the comparative analysis of stress-strain states of alternative solutions. The adopted solution enabled the repair and reconstruction in field conditions, without previously dismantling components of the BWE superstructure. Moreover, the regular maintenance procedure has not been impeded. Experimental analysis of the stress state of the reconstructed slewing platform in regular working conditions has confirmed the validity of the reconstruction design. After the reconstruction the BWE has dug up more than 2.9 x 10(6) m(3) of overburden. Visual inspection of slewing platform proved that there are no defects in the structure.
PB  - Pergamon-Elsevier Science Ltd, Oxford
T2  - Engineering Failure Analysis
T1  - Cracks, repair and reconstruction of bucket wheel excavator slewing platform
EP  - 1642
IS  - 5
SP  - 1631
VL  - 16
DO  - 10.1016/j.engfailanal.2008.11.009
ER  - 

@article{
author = "Bošnjak, Srđan and Petković, Zoran D. and Zrnić, Nenad and Simić, Goran and Simonović, Aleksandar",
year = "2009",
abstract = "This paper discusses the results of the investigation of occurrence of cracks in the structure of bucket wheel excavator (BWE) slewing platform, the repair procedure and the reconstruction of the slewing platform. The results of the finite elements analysis (FEA) point out the pronounced stress concentration in the zones of crack occurrence. The values of calculated stresses in the said zones exceed the yield stress of the material. The design solution for the slewing platform reconstruction is chosen based on the comparative analysis of stress-strain states of alternative solutions. The adopted solution enabled the repair and reconstruction in field conditions, without previously dismantling components of the BWE superstructure. Moreover, the regular maintenance procedure has not been impeded. Experimental analysis of the stress state of the reconstructed slewing platform in regular working conditions has confirmed the validity of the reconstruction design. After the reconstruction the BWE has dug up more than 2.9 x 10(6) m(3) of overburden. Visual inspection of slewing platform proved that there are no defects in the structure.",
publisher = "Pergamon-Elsevier Science Ltd, Oxford",
journal = "Engineering Failure Analysis",
title = "Cracks, repair and reconstruction of bucket wheel excavator slewing platform",
pages = "1642-1631",
number = "5",
volume = "16",
doi = "10.1016/j.engfailanal.2008.11.009"
}

Bošnjak, S., Petković, Z. D., Zrnić, N., Simić, G.,& Simonović, A.. (2009). Cracks, repair and reconstruction of bucket wheel excavator slewing platform. in Engineering Failure Analysis
Pergamon-Elsevier Science Ltd, Oxford., 16(5), 1631-1642.
https://doi.org/10.1016/j.engfailanal.2008.11.009

Bošnjak S, Petković ZD, Zrnić N, Simić G, Simonović A. Cracks, repair and reconstruction of bucket wheel excavator slewing platform. in Engineering Failure Analysis. 2009;16(5):1631-1642.
doi:10.1016/j.engfailanal.2008.11.009 .

Bošnjak, Srđan, Petković, Zoran D., Zrnić, Nenad, Simić, Goran, Simonović, Aleksandar, "Cracks, repair and reconstruction of bucket wheel excavator slewing platform" in Engineering Failure Analysis, 16, no. 5 (2009):1631-1642,
https://doi.org/10.1016/j.engfailanal.2008.11.009 . .

TY  - JOUR
AU  - Međo, Bojan
AU  - Rakin, Marko
AU  - Zrilić, Milorad
AU  - Putić, Slaviša
AU  - Sedmak, Aleksandar
PY  - 2009
UR  - https://machinery.mas.bg.ac.rs/handle/123456789/980
AB  - We analyze the level of damage to 14MoV63 steel for steam pipelines under the conditions of crack-growth initiation according to the mechanism of ductile fracture. The state of the material after service for about 100,000 h at the power plant is estimated by using a combined experimental and numerical procedure based on the local approach to fracture. The level of damage is determined by analyzing the material taken from the pipeline (aged) and new (virgin) material of the same grade (for the sake of comparison). The critical values of the J-integral are determined on single-edge notched bend (SENB) specimens both experimentally and by using a simplified procedure of local approach without knowing the microstructural parameters. Two micromechanical models are applied: the Rice - Tracey models modified by Beremin (uncoupled) and the complete Gurson model (coupled).
PB  - Springer, New York
T2  - Materials Science
T1  - Micromechanical estimates of the critical values of j-integral for the steel of steam pipelines
EP  - 531
IS  - 4
SP  - 523
VL  - 45
DO  - 10.1007/s11003-010-9210-7
ER  - 

@article{
author = "Međo, Bojan and Rakin, Marko and Zrilić, Milorad and Putić, Slaviša and Sedmak, Aleksandar",
year = "2009",
abstract = "We analyze the level of damage to 14MoV63 steel for steam pipelines under the conditions of crack-growth initiation according to the mechanism of ductile fracture. The state of the material after service for about 100,000 h at the power plant is estimated by using a combined experimental and numerical procedure based on the local approach to fracture. The level of damage is determined by analyzing the material taken from the pipeline (aged) and new (virgin) material of the same grade (for the sake of comparison). The critical values of the J-integral are determined on single-edge notched bend (SENB) specimens both experimentally and by using a simplified procedure of local approach without knowing the microstructural parameters. Two micromechanical models are applied: the Rice - Tracey models modified by Beremin (uncoupled) and the complete Gurson model (coupled).",
publisher = "Springer, New York",
journal = "Materials Science",
title = "Micromechanical estimates of the critical values of j-integral for the steel of steam pipelines",
pages = "531-523",
number = "4",
volume = "45",
doi = "10.1007/s11003-010-9210-7"
}

Međo, B., Rakin, M., Zrilić, M., Putić, S.,& Sedmak, A.. (2009). Micromechanical estimates of the critical values of j-integral for the steel of steam pipelines. in Materials Science
Springer, New York., 45(4), 523-531.
https://doi.org/10.1007/s11003-010-9210-7

Međo B, Rakin M, Zrilić M, Putić S, Sedmak A. Micromechanical estimates of the critical values of j-integral for the steel of steam pipelines. in Materials Science. 2009;45(4):523-531.
doi:10.1007/s11003-010-9210-7 .

Međo, Bojan, Rakin, Marko, Zrilić, Milorad, Putić, Slaviša, Sedmak, Aleksandar, "Micromechanical estimates of the critical values of j-integral for the steel of steam pipelines" in Materials Science, 45, no. 4 (2009):523-531,
https://doi.org/10.1007/s11003-010-9210-7 . .

TY  - JOUR
AU  - Obradović, Aleksandar
AU  - Mladenović, Nikola
AU  - Marković, Saša
PY  - 2008
UR  - https://machinery.mas.bg.ac.rs/handle/123456789/797
AB  - Razmatra se minimizacija vremena kretanja krutog tela uz neizmenjenu vrednost mehaničke energije. Za generalisane koordinate uzete su koordinate centra masa i Ojlerovi uglovi, čije su vrednosti zadate na početku i kraju intervala kretanja. Zadatak je rešen primenom Pontrjaginovog principa maksimuma. Numeričko rešenje dvotačkastog graničnog problema dobijeno je metodom konačnih razlika za sisteme običnih diferencijalnih jednačina. .
AB  - The time interval minimization of rigid body motion with constant mechanical energy has been considered in this paper. Generalized coordinates are Cartesian's coordinates of mass center and the Euler's angles, which are specified at the initial and the final position. The problem has been solved by the application of the Pontryagin's principle. Finite difference method has been applied in order to obtain the solution of the two-point boundary value problem. .
PB  - Univerzitet u Beogradu - Mašinski fakultet, Beograd
T2  - FME Transactions
T1  - Brahistohrono opšte kretanje krutog tela
T1  - Brachistochronic rigid body general motion
EP  - 112
IS  - 3
SP  - 109
VL  - 36
UR  - https://hdl.handle.net/21.15107/rcub_machinery_797
ER  - 

@article{
author = "Obradović, Aleksandar and Mladenović, Nikola and Marković, Saša",
year = "2008",
abstract = "Razmatra se minimizacija vremena kretanja krutog tela uz neizmenjenu vrednost mehaničke energije. Za generalisane koordinate uzete su koordinate centra masa i Ojlerovi uglovi, čije su vrednosti zadate na početku i kraju intervala kretanja. Zadatak je rešen primenom Pontrjaginovog principa maksimuma. Numeričko rešenje dvotačkastog graničnog problema dobijeno je metodom konačnih razlika za sisteme običnih diferencijalnih jednačina. ., The time interval minimization of rigid body motion with constant mechanical energy has been considered in this paper. Generalized coordinates are Cartesian's coordinates of mass center and the Euler's angles, which are specified at the initial and the final position. The problem has been solved by the application of the Pontryagin's principle. Finite difference method has been applied in order to obtain the solution of the two-point boundary value problem. .",
publisher = "Univerzitet u Beogradu - Mašinski fakultet, Beograd",
journal = "FME Transactions",
title = "Brahistohrono opšte kretanje krutog tela, Brachistochronic rigid body general motion",
pages = "112-109",
number = "3",
volume = "36",
url = "https://hdl.handle.net/21.15107/rcub_machinery_797"
}

Obradović, A., Mladenović, N.,& Marković, S.. (2008). Brahistohrono opšte kretanje krutog tela. in FME Transactions
Univerzitet u Beogradu - Mašinski fakultet, Beograd., 36(3), 109-112.
https://hdl.handle.net/21.15107/rcub_machinery_797

Obradović A, Mladenović N, Marković S. Brahistohrono opšte kretanje krutog tela. in FME Transactions. 2008;36(3):109-112.
https://hdl.handle.net/21.15107/rcub_machinery_797 .

Obradović, Aleksandar, Mladenović, Nikola, Marković, Saša, "Brahistohrono opšte kretanje krutog tela" in FME Transactions, 36, no. 3 (2008):109-112,
https://hdl.handle.net/21.15107/rcub_machinery_797 .

TY  - JOUR
AU  - Rusov, Srđan
AU  - Mitrović, Zoran
AU  - Mladenović, Nikola
PY  - 2008
UR  - https://machinery.mas.bg.ac.rs/handle/123456789/807
AB  - U radu se razmatra problem optimizacije funkcije upravljanja kontrolera aktivnog sistema naginjanja kod vozova velikih brzina, zasnovan na analizi različitih mehaničkih modela železničkih vozila velikih brzina sa samonaginjanjem. U skladu sa klasičnim mehaničkim modelom vozila formiran je odgovarajući mehanički model u obliku sistema krutih tela predstavljenog u vidu kinematičkih lanaca. Formiran je odgovarajući blok dijagram i funkcija upravljanja aktivnog sistema samonaginjanja vozila sa elektrohidrauličkim aktuatorima, za čiju osnovu je predložen osavremenjeni mehanički model vozila, koji omogućava optimalnu formu diferencijalnih jednačina kretanja vozila u koje je integrisana odgovarajuća upravljačka funkcija. .
AB  - The present paper deals with the problem of controller function in active system of tilting in high speed railway vehicles, which is based on different mechanical models of railway vehicles. According to the classical mechanical model of the vehicle, an appropriate mechanical multibody system is formed in this paper. In conformity with the basic constructive parameters of the active system of tilting, guidance control function of actuator operating process is formed. Basic mechanical model, in dependence of characteristic constructive parameters, according to the theory of robust robotic control is given in the form of closed kinematics chain with branching. For the concrete model of high speed railway vehicle, differential equations of motion are obtained in the form optimal for control function evaluation and calculation.
PB  - Univerzitet u Beogradu - Mašinski fakultet, Beograd
T2  - FME Transactions
T1  - Funkcija upravljanja aktivnim naginjanjem voza zasnovana na odgovarajućem mehaničkom sistemu krutih tela
T1  - Control function on active tilting train based on an appropriate multibody mechanical system
EP  - 102
IS  - 3
SP  - 99
VL  - 36
UR  - https://hdl.handle.net/21.15107/rcub_machinery_807
ER  - 

@article{
author = "Rusov, Srđan and Mitrović, Zoran and Mladenović, Nikola",
year = "2008",
abstract = "U radu se razmatra problem optimizacije funkcije upravljanja kontrolera aktivnog sistema naginjanja kod vozova velikih brzina, zasnovan na analizi različitih mehaničkih modela železničkih vozila velikih brzina sa samonaginjanjem. U skladu sa klasičnim mehaničkim modelom vozila formiran je odgovarajući mehanički model u obliku sistema krutih tela predstavljenog u vidu kinematičkih lanaca. Formiran je odgovarajući blok dijagram i funkcija upravljanja aktivnog sistema samonaginjanja vozila sa elektrohidrauličkim aktuatorima, za čiju osnovu je predložen osavremenjeni mehanički model vozila, koji omogućava optimalnu formu diferencijalnih jednačina kretanja vozila u koje je integrisana odgovarajuća upravljačka funkcija. ., The present paper deals with the problem of controller function in active system of tilting in high speed railway vehicles, which is based on different mechanical models of railway vehicles. According to the classical mechanical model of the vehicle, an appropriate mechanical multibody system is formed in this paper. In conformity with the basic constructive parameters of the active system of tilting, guidance control function of actuator operating process is formed. Basic mechanical model, in dependence of characteristic constructive parameters, according to the theory of robust robotic control is given in the form of closed kinematics chain with branching. For the concrete model of high speed railway vehicle, differential equations of motion are obtained in the form optimal for control function evaluation and calculation.",
publisher = "Univerzitet u Beogradu - Mašinski fakultet, Beograd",
journal = "FME Transactions",
title = "Funkcija upravljanja aktivnim naginjanjem voza zasnovana na odgovarajućem mehaničkom sistemu krutih tela, Control function on active tilting train based on an appropriate multibody mechanical system",
pages = "102-99",
number = "3",
volume = "36",
url = "https://hdl.handle.net/21.15107/rcub_machinery_807"
}

Rusov, S., Mitrović, Z.,& Mladenović, N.. (2008). Funkcija upravljanja aktivnim naginjanjem voza zasnovana na odgovarajućem mehaničkom sistemu krutih tela. in FME Transactions
Univerzitet u Beogradu - Mašinski fakultet, Beograd., 36(3), 99-102.
https://hdl.handle.net/21.15107/rcub_machinery_807

Rusov S, Mitrović Z, Mladenović N. Funkcija upravljanja aktivnim naginjanjem voza zasnovana na odgovarajućem mehaničkom sistemu krutih tela. in FME Transactions. 2008;36(3):99-102.
https://hdl.handle.net/21.15107/rcub_machinery_807 .

Rusov, Srđan, Mitrović, Zoran, Mladenović, Nikola, "Funkcija upravljanja aktivnim naginjanjem voza zasnovana na odgovarajućem mehaničkom sistemu krutih tela" in FME Transactions, 36, no. 3 (2008):99-102,
https://hdl.handle.net/21.15107/rcub_machinery_807 .