TY  - CONF
AU  - Praštalo, Petar
AU  - Brajović, Ljiljana
AU  - Prodanović, Dušan
PY  - 2023
UR  - https://grafar.grf.bg.ac.rs/handle/123456789/3455
AB  - Vlažnost zemljišta je jedan od važnijih parametara u modeliranju i analizi podzemnih
voda, poljoprivredi, ekologiji i sl. Monitoring vlažnosti omogućava upravljanje vodnovazdušnim režimom zemljišta čime se obezbjeđuju bolji uslovi za razvoj biljaka i
povećanje prinosa. Određivanje vlažnosti zemljišta laboratorijskim metodama zahtijeva
značajna materijalna sredstva kao i određeno vrijeme. Razvojem tehnologije danas su
dostupni relativno jeftini senzori koji omogućavaju na vrlo efikasan način monitoring
vlažnosti na terenu. U ovom radu istražena je mogućnost korišćenja jeftinih senzora za
mjerenje vlažnosti na uzorku humusa u laboratorijskim uslovima. Urađena je kalibracija
senzora za analizirani uzorak zemljišta korišćenog u eksperimentu na kojem je
sprovedeno mjerenje vlažnosti, a rezultati sprovedenog istraživanja provjereni su
pomoću Hydrus 1D modela.
PB  - Department of Civil Engineering and Geodesy, Faculty of Technical Sciences, University of Novi Sad
C3  - Zbornik radova: 16. međunarodna naučna konferencija „Integration, Novelty, Design, Interdisciplinarity, Sustainability" iNDiS 2023, Novi Sad, Srbija, 16-17. novembar 2023
T1  - Monitoring vlažnosti zemljišta korišćenjem jeftinih  senzora
EP  - 29
SP  - 17
UR  - https://hdl.handle.net/21.15107/rcub_grafar_3455
ER  - 

@conference{
author = "Praštalo, Petar and Brajović, Ljiljana and Prodanović, Dušan",
year = "2023",
abstract = "Vlažnost zemljišta je jedan od važnijih parametara u modeliranju i analizi podzemnih
voda, poljoprivredi, ekologiji i sl. Monitoring vlažnosti omogućava upravljanje vodnovazdušnim režimom zemljišta čime se obezbjeđuju bolji uslovi za razvoj biljaka i
povećanje prinosa. Određivanje vlažnosti zemljišta laboratorijskim metodama zahtijeva
značajna materijalna sredstva kao i određeno vrijeme. Razvojem tehnologije danas su
dostupni relativno jeftini senzori koji omogućavaju na vrlo efikasan način monitoring
vlažnosti na terenu. U ovom radu istražena je mogućnost korišćenja jeftinih senzora za
mjerenje vlažnosti na uzorku humusa u laboratorijskim uslovima. Urađena je kalibracija
senzora za analizirani uzorak zemljišta korišćenog u eksperimentu na kojem je
sprovedeno mjerenje vlažnosti, a rezultati sprovedenog istraživanja provjereni su
pomoću Hydrus 1D modela.",
publisher = "Department of Civil Engineering and Geodesy, Faculty of Technical Sciences, University of Novi Sad",
journal = "Zbornik radova: 16. međunarodna naučna konferencija „Integration, Novelty, Design, Interdisciplinarity, Sustainability" iNDiS 2023, Novi Sad, Srbija, 16-17. novembar 2023",
title = "Monitoring vlažnosti zemljišta korišćenjem jeftinih  senzora",
pages = "29-17",
url = "https://hdl.handle.net/21.15107/rcub_grafar_3455"
}

Praštalo, P., Brajović, L.,& Prodanović, D.. (2023). Monitoring vlažnosti zemljišta korišćenjem jeftinih  senzora. in Zbornik radova: 16. međunarodna naučna konferencija „Integration, Novelty, Design, Interdisciplinarity, Sustainability" iNDiS 2023, Novi Sad, Srbija, 16-17. novembar 2023
Department of Civil Engineering and Geodesy, Faculty of Technical Sciences, University of Novi Sad., 17-29.
https://hdl.handle.net/21.15107/rcub_grafar_3455

Praštalo P, Brajović L, Prodanović D. Monitoring vlažnosti zemljišta korišćenjem jeftinih  senzora. in Zbornik radova: 16. međunarodna naučna konferencija „Integration, Novelty, Design, Interdisciplinarity, Sustainability" iNDiS 2023, Novi Sad, Srbija, 16-17. novembar 2023. 2023;:17-29.
https://hdl.handle.net/21.15107/rcub_grafar_3455 .

Praštalo, Petar, Brajović, Ljiljana, Prodanović, Dušan, "Monitoring vlažnosti zemljišta korišćenjem jeftinih  senzora" in Zbornik radova: 16. međunarodna naučna konferencija „Integration, Novelty, Design, Interdisciplinarity, Sustainability" iNDiS 2023, Novi Sad, Srbija, 16-17. novembar 2023 (2023):17-29,
https://hdl.handle.net/21.15107/rcub_grafar_3455 .

TY  - JOUR
AU  - Gojković, Zoran
AU  - Kilibarda, Milan
AU  - Brajović, Ljiljana
AU  - Marjanović, Miloš
AU  - Milutinović, Aleksandar
AU  - Ganić, Aleksandar
PY  - 2023
UR  - https://grafar.grf.bg.ac.rs/handle/123456789/3458
AB  - Open pit coal mining affects surrounding populated areas, resulting in terrain surface deformation. Surface deformation should be monitored as often as possible to control deformations and prevent potential incidents. This paper analyzes time series deformation estimated from the Sentinel-1 satellite images using the Persistent Scatterer Interferometry method to monitor subsidence rates caused by open pit mining activities. It is possible to measure deformations using classical geodetic methods, but those are rarely used in practice because they are time-consuming and expensive for application in large areas. Using the open access radar images from the Sentinel-1 mission, 513 images from the repository were downloaded between October 2016 and the end of December 2020. We present the processing steps in detail in order to establish a workflow for the automated processing of vertical displacement estimation using open source tools; a total of 402 images were processed: 215 images belonged to the ascending satellite orbit, 187 images belonged to the descending orbit, and 111 images were rejected because of adverse weather conditions. The PS InSAR technique has never been used for the mines of the Republic of Serbia or for land surveying practices related to deformation monitoring. The results based on the Sentinel-1 images were compared with results from geodetic leveling and with neotectonic uplift trends. The trend lines of vertical displacement obtained from PS and corresponding leveling are significantly similar (a Pearson correlation of 85% with a p-value of 0.015). The final evaluation reported results of vertical displacements at the leveling benchmark of −3.4 mm/year with the PS InSAR method and −2.7 mm/year with the leveling method. A comparison of the PS vertical displacements with a settlement model fits reasonably, suggesting that the measurements are valid. As four years of PS time series data is insufficient to establish undisputable conclusions on the neotectonics uplift, extending the time series (covering at least a decade) implies that this approach will become attractive in future neotectonic uplift trend estimations. This study illustrates not only the ability of Sentinel-1 data in mapping vertical deformations, but the obtained results could also be used for geohazard monitoring and land monitoring in general for the area of interest.
PB  - MDPI
T2  - Remote Sensing
T1  - Ground Surface Subsidence Monitoring Using Sentinel-1 in the “Kostolac” Open Pit Coal Mine
IS  - 10
SP  - 2519
VL  - 15
DO  - 10.3390/rs15102519
ER  - 

@article{
author = "Gojković, Zoran and Kilibarda, Milan and Brajović, Ljiljana and Marjanović, Miloš and Milutinović, Aleksandar and Ganić, Aleksandar",
year = "2023",
abstract = "Open pit coal mining affects surrounding populated areas, resulting in terrain surface deformation. Surface deformation should be monitored as often as possible to control deformations and prevent potential incidents. This paper analyzes time series deformation estimated from the Sentinel-1 satellite images using the Persistent Scatterer Interferometry method to monitor subsidence rates caused by open pit mining activities. It is possible to measure deformations using classical geodetic methods, but those are rarely used in practice because they are time-consuming and expensive for application in large areas. Using the open access radar images from the Sentinel-1 mission, 513 images from the repository were downloaded between October 2016 and the end of December 2020. We present the processing steps in detail in order to establish a workflow for the automated processing of vertical displacement estimation using open source tools; a total of 402 images were processed: 215 images belonged to the ascending satellite orbit, 187 images belonged to the descending orbit, and 111 images were rejected because of adverse weather conditions. The PS InSAR technique has never been used for the mines of the Republic of Serbia or for land surveying practices related to deformation monitoring. The results based on the Sentinel-1 images were compared with results from geodetic leveling and with neotectonic uplift trends. The trend lines of vertical displacement obtained from PS and corresponding leveling are significantly similar (a Pearson correlation of 85% with a p-value of 0.015). The final evaluation reported results of vertical displacements at the leveling benchmark of −3.4 mm/year with the PS InSAR method and −2.7 mm/year with the leveling method. A comparison of the PS vertical displacements with a settlement model fits reasonably, suggesting that the measurements are valid. As four years of PS time series data is insufficient to establish undisputable conclusions on the neotectonics uplift, extending the time series (covering at least a decade) implies that this approach will become attractive in future neotectonic uplift trend estimations. This study illustrates not only the ability of Sentinel-1 data in mapping vertical deformations, but the obtained results could also be used for geohazard monitoring and land monitoring in general for the area of interest.",
publisher = "MDPI",
journal = "Remote Sensing",
title = "Ground Surface Subsidence Monitoring Using Sentinel-1 in the “Kostolac” Open Pit Coal Mine",
number = "10",
pages = "2519",
volume = "15",
doi = "10.3390/rs15102519"
}

Gojković, Z., Kilibarda, M., Brajović, L., Marjanović, M., Milutinović, A.,& Ganić, A.. (2023). Ground Surface Subsidence Monitoring Using Sentinel-1 in the “Kostolac” Open Pit Coal Mine. in Remote Sensing
MDPI., 15(10), 2519.
https://doi.org/10.3390/rs15102519

Gojković Z, Kilibarda M, Brajović L, Marjanović M, Milutinović A, Ganić A. Ground Surface Subsidence Monitoring Using Sentinel-1 in the “Kostolac” Open Pit Coal Mine. in Remote Sensing. 2023;15(10):2519.
doi:10.3390/rs15102519 .

Gojković, Zoran, Kilibarda, Milan, Brajović, Ljiljana, Marjanović, Miloš, Milutinović, Aleksandar, Ganić, Aleksandar, "Ground Surface Subsidence Monitoring Using Sentinel-1 in the “Kostolac” Open Pit Coal Mine" in Remote Sensing, 15, no. 10 (2023):2519,
https://doi.org/10.3390/rs15102519 . .

TY  - CONF
AU  - Malović, Miodrag
AU  - Vukanić, Vera
AU  - Jevremović, Darko
AU  - Brajović, Ljiljana
PY  - 2023
UR  - https://grafar.grf.bg.ac.rs/handle/123456789/3384
AB  - Pearson’s and Spearman’s methods are most often used in popular software packages to calculate the correlation coefficient between two variables in natural sciences. The (1) difference between them is that the Pearson’s method takes actual numerical values into account whereas the Spearman’s operates with their ranks. Ranking is often efficient in dealing with nonlinearities and outliers in the data. However, not both independent (x) and outcome (y) variable have to be suitable for this. We propose not to rank the independent variable in case it comes sine-shaped. Most notable example of such a variable in nature is the temperature. It is sine-shaped due to day-night and summer-winter transitions. It does not contain many outliers, not only due to the shape, but also because it is often sampled at multiple points and averaged (to be linked with a single outcome variable observation). The proposed method is evaluated in simulations and with experimental data obtained in South Adriatic zooplankton research. Practical advices on how to apply it using popular software tools are given.
PB  - Institute of Electrical and Electronics Engineers Inc
C3  - Proccedings of  10th International Conference on Electrical, Electronic and Computing Engineering (IcETRAN), 05-08 June, East Sarajevo, Bosnia and Herzegovina 2023
T1  - Mixed Spearman’s Correlation Suitability for Sine-Shaped Independent Variables in Natural Sciences
DO  - 10.1109/IcETRAN59631.2023.10192143
ER  - 

@conference{
author = "Malović, Miodrag and Vukanić, Vera and Jevremović, Darko and Brajović, Ljiljana",
year = "2023",
abstract = "Pearson’s and Spearman’s methods are most often used in popular software packages to calculate the correlation coefficient between two variables in natural sciences. The (1) difference between them is that the Pearson’s method takes actual numerical values into account whereas the Spearman’s operates with their ranks. Ranking is often efficient in dealing with nonlinearities and outliers in the data. However, not both independent (x) and outcome (y) variable have to be suitable for this. We propose not to rank the independent variable in case it comes sine-shaped. Most notable example of such a variable in nature is the temperature. It is sine-shaped due to day-night and summer-winter transitions. It does not contain many outliers, not only due to the shape, but also because it is often sampled at multiple points and averaged (to be linked with a single outcome variable observation). The proposed method is evaluated in simulations and with experimental data obtained in South Adriatic zooplankton research. Practical advices on how to apply it using popular software tools are given.",
publisher = "Institute of Electrical and Electronics Engineers Inc",
journal = "Proccedings of  10th International Conference on Electrical, Electronic and Computing Engineering (IcETRAN), 05-08 June, East Sarajevo, Bosnia and Herzegovina 2023",
title = "Mixed Spearman’s Correlation Suitability for Sine-Shaped Independent Variables in Natural Sciences",
doi = "10.1109/IcETRAN59631.2023.10192143"
}

Malović, M., Vukanić, V., Jevremović, D.,& Brajović, L.. (2023). Mixed Spearman’s Correlation Suitability for Sine-Shaped Independent Variables in Natural Sciences. in Proccedings of  10th International Conference on Electrical, Electronic and Computing Engineering (IcETRAN), 05-08 June, East Sarajevo, Bosnia and Herzegovina 2023
Institute of Electrical and Electronics Engineers Inc..
https://doi.org/10.1109/IcETRAN59631.2023.10192143

Malović M, Vukanić V, Jevremović D, Brajović L. Mixed Spearman’s Correlation Suitability for Sine-Shaped Independent Variables in Natural Sciences. in Proccedings of  10th International Conference on Electrical, Electronic and Computing Engineering (IcETRAN), 05-08 June, East Sarajevo, Bosnia and Herzegovina 2023. 2023;.
doi:10.1109/IcETRAN59631.2023.10192143 .

Malović, Miodrag, Vukanić, Vera, Jevremović, Darko, Brajović, Ljiljana, "Mixed Spearman’s Correlation Suitability for Sine-Shaped Independent Variables in Natural Sciences" in Proccedings of  10th International Conference on Electrical, Electronic and Computing Engineering (IcETRAN), 05-08 June, East Sarajevo, Bosnia and Herzegovina 2023 (2023),
https://doi.org/10.1109/IcETRAN59631.2023.10192143 . .

TY  - CONF
AU  - Joksimović, Novak
AU  - Brajović, Ljiljana
PY  - 2023
UR  - https://grafar.grf.bg.ac.rs/handle/123456789/3385
AB  - Structural health monitoring (SHM) has gained significant attention in the field of civil engineering due to effective maintenance of structures, particularly bridges. However, traditional SHM methods have limitations in providing accurate and continuous data, which has led researchers to explore new technologies, one of which is fiber optic sensor (FOS) monitoring. This paper provides a comprehensivereview of the use of FOS in bridge SHM, highlighting the challenges and potential of this technology. FOS are convenient for SHM due to their high accuracy, immunity toelectromagnetic interference, and capability of working in harsh environments. They are particularly suitable for quasi-distributive anddistributive measurement systems on capital civil engineering structures. FOS can be utilized to measurevarious parameters, including deformation, temperature, and strain. In bridge constructions, FOS can beinstalled in multiple locations.
Deformation measurements using FOS can provide accurate information on the displacement and
deflection of the bridge, which can help in detecting abnormalities or damages. Temperature
measurements using FOS can detect effects of thermal load on bridges, which can cause significant damage. Strain measurements using FOS can help describe the stress distribution in 
the bridge, which can be used for maintenance purposes. FOS-based SHM systems can provide real-time and continuous data, which can help in detecting any potential problems at an early stage and preventing catastrophic failures. The use of FOS in SHM of bridges has been extensively researched and demonstrated in various studies. However, challenges such as installation, calibration, and interpretation of the data require further research.
The paper will discuss the potential of FOS-based SHM systems in improving the safety and reliability of bridge constructions. It will also highlight the challenges related to FOS installation, calibration, and data interpretation and provide insights into future research directions for developing more robust and cost-effective FOS-based SHM systems.
PB  - MASE - Macedonian Association of Structural Engineers Faculty of Civil Engineering, Blvd. Partizanski odredi No. 24 P.Box. 560, 1000 Skopje, Republic of North Macedonia
C3  - Proceedings of the 20th International Symposium of MASE, Skopje, North Macedonia, 28–29 September 2023
T1  - Challenges and potential of fiber optic sensors for structural health monitoring of bridges: a review
UR  - https://hdl.handle.net/21.15107/rcub_grafar_3385
ER  - 

@conference{
author = "Joksimović, Novak and Brajović, Ljiljana",
year = "2023",
abstract = "Structural health monitoring (SHM) has gained significant attention in the field of civil engineering due to effective maintenance of structures, particularly bridges. However, traditional SHM methods have limitations in providing accurate and continuous data, which has led researchers to explore new technologies, one of which is fiber optic sensor (FOS) monitoring. This paper provides a comprehensivereview of the use of FOS in bridge SHM, highlighting the challenges and potential of this technology. FOS are convenient for SHM due to their high accuracy, immunity toelectromagnetic interference, and capability of working in harsh environments. They are particularly suitable for quasi-distributive anddistributive measurement systems on capital civil engineering structures. FOS can be utilized to measurevarious parameters, including deformation, temperature, and strain. In bridge constructions, FOS can beinstalled in multiple locations.
Deformation measurements using FOS can provide accurate information on the displacement and
deflection of the bridge, which can help in detecting abnormalities or damages. Temperature
measurements using FOS can detect effects of thermal load on bridges, which can cause significant damage. Strain measurements using FOS can help describe the stress distribution in 
the bridge, which can be used for maintenance purposes. FOS-based SHM systems can provide real-time and continuous data, which can help in detecting any potential problems at an early stage and preventing catastrophic failures. The use of FOS in SHM of bridges has been extensively researched and demonstrated in various studies. However, challenges such as installation, calibration, and interpretation of the data require further research.
The paper will discuss the potential of FOS-based SHM systems in improving the safety and reliability of bridge constructions. It will also highlight the challenges related to FOS installation, calibration, and data interpretation and provide insights into future research directions for developing more robust and cost-effective FOS-based SHM systems.",
publisher = "MASE - Macedonian Association of Structural Engineers Faculty of Civil Engineering, Blvd. Partizanski odredi No. 24 P.Box. 560, 1000 Skopje, Republic of North Macedonia",
journal = "Proceedings of the 20th International Symposium of MASE, Skopje, North Macedonia, 28–29 September 2023",
title = "Challenges and potential of fiber optic sensors for structural health monitoring of bridges: a review",
url = "https://hdl.handle.net/21.15107/rcub_grafar_3385"
}

Joksimović, N.,& Brajović, L.. (2023). Challenges and potential of fiber optic sensors for structural health monitoring of bridges: a review. in Proceedings of the 20th International Symposium of MASE, Skopje, North Macedonia, 28–29 September 2023
MASE - Macedonian Association of Structural Engineers Faculty of Civil Engineering, Blvd. Partizanski odredi No. 24 P.Box. 560, 1000 Skopje, Republic of North Macedonia..
https://hdl.handle.net/21.15107/rcub_grafar_3385

Joksimović N, Brajović L. Challenges and potential of fiber optic sensors for structural health monitoring of bridges: a review. in Proceedings of the 20th International Symposium of MASE, Skopje, North Macedonia, 28–29 September 2023. 2023;.
https://hdl.handle.net/21.15107/rcub_grafar_3385 .

Joksimović, Novak, Brajović, Ljiljana, "Challenges and potential of fiber optic sensors for structural health monitoring of bridges: a review" in Proceedings of the 20th International Symposium of MASE, Skopje, North Macedonia, 28–29 September 2023 (2023),
https://hdl.handle.net/21.15107/rcub_grafar_3385 .

TY  - JOUR
AU  - Petković, Dušan
AU  - Brajović, Ljiljana
AU  - Vasilić, Violeta
AU  - Босиочић, Станислава
PY  - 2023
UR  - https://www.sits.org.rs/textview.php?file=917.html
UR  - https://scindeks.ceon.rs/Article.aspx?artid=0040-21762301021P
UR  - https://grafar.grf.bg.ac.rs/handle/123456789/3043
AB  - Višefrekvencijski GNSS satelitski signali i njihova dostupnost omogućavaju istraživanja u nediferenciranom i nekombinovanom modelu u kome je pojedinačni signal na svakoj frekvenciji odgovarajuće nezavisno opažanje. Ovakve mogućnosti izazivaju veliko interesovanje ne samo u geodetskim istraživanjima već i u mnogim oblastima primene GNSS opažanja. Na geometrijskoj putanji signala između satelita i prijemnika, značajni izvor grešaka GNSS merenja dolazi zbog sredine prostiranja elektromagnetskih talasa. Greške koje se pripisuju prostiranju signala su jonosferski i troposferski uticaji. Navedeni izvori grešaka značajno utiču na kvalitet određenih pseudodužina, pa samim time i na kvalitet određenog položaja prijemnika u vidu trodimenzionalnih koordinata. U radu je prikazana analiza i određivanje jonosferskog kašnjenja GNSS satelitskih signala na osnovu određivanja Total Electron Content – TEC na pet stanica (Beograd, Leskovac, Sombor, Zaječar i Kraljevo) na prostoru Republike Srbije. U cilju određivanja vrednosti TEC-a, korišćen je softver pod nazivom „GPS-TEC analysis“ razvijen  u okviru Institute for Scientific Research, Boston College, USA, koji omogućava određivanje TEC vrednosti na  putanji između satelita i prijemnika. Prikupljanje podataka izvršeno je u okviru 2022. godine tako da merne sesije obuhvate karakteristične datume u okviru godine kada se očekuju najveća kolebanja u kontekstu sezonskih varijacija.
AB  - Multi-frequency GNSS satellite signals and their availability enable research in undifferentiated and uncombined models in which a single signal at each frequency is a corresponding independent observation. Such possibilities are reflected by the significant interest in geodetic research as well as in many areas of application of GNSS observation. On the geometric path of the signal between the satellite and the receiver, a significant source of GNSS measurement errors comes from the medium of propagation of electromagnetic waves. Errors attributed to signal propagation are ionospheric and tropospheric signal delay. The mentioned error sources significantly affect the quality of certain pseudorange and, thus, the quality of the receiver's position in the form of three-dimensional coordinates. This paper presents the analysis and determination of the ionospheric delay of GNSS satellite signals based on the determination of Total Electron Content - TEC at five stations (Beograd, Leskovac, Sombor, Zaječar, and Kraljevo) in the territory of the Republic of Serbia. In order to determine TEC values, the software called "GPS-TEC analysis" developed within the Institute for Scientific Research, Boston College, USA was used, which enables the determination of the TEC value on the path between the satellite and the receiver. The data collection was carried out within the year 2022 so that the measurement sessions include characteristic dates when the most significant fluctuations are expected in the context of seasonal variations.
PB  - Savez inženjera i tehničara Srbije, Beograd
T2  - Tehnika
T1  - Doprinos određivanju jonosferskog kašnjenja GNSS satelitskih signala na teritoriji Republike Srbije
EP  - 28
IS  - 1
SP  - 21
VL  - 78
DO  - 10.5937/tehnika2301021P
ER  - 

@article{
author = "Petković, Dušan and Brajović, Ljiljana and Vasilić, Violeta and Босиочић, Станислава",
year = "2023",
abstract = "Višefrekvencijski GNSS satelitski signali i njihova dostupnost omogućavaju istraživanja u nediferenciranom i nekombinovanom modelu u kome je pojedinačni signal na svakoj frekvenciji odgovarajuće nezavisno opažanje. Ovakve mogućnosti izazivaju veliko interesovanje ne samo u geodetskim istraživanjima već i u mnogim oblastima primene GNSS opažanja. Na geometrijskoj putanji signala između satelita i prijemnika, značajni izvor grešaka GNSS merenja dolazi zbog sredine prostiranja elektromagnetskih talasa. Greške koje se pripisuju prostiranju signala su jonosferski i troposferski uticaji. Navedeni izvori grešaka značajno utiču na kvalitet određenih pseudodužina, pa samim time i na kvalitet određenog položaja prijemnika u vidu trodimenzionalnih koordinata. U radu je prikazana analiza i određivanje jonosferskog kašnjenja GNSS satelitskih signala na osnovu određivanja Total Electron Content – TEC na pet stanica (Beograd, Leskovac, Sombor, Zaječar i Kraljevo) na prostoru Republike Srbije. U cilju određivanja vrednosti TEC-a, korišćen je softver pod nazivom „GPS-TEC analysis“ razvijen  u okviru Institute for Scientific Research, Boston College, USA, koji omogućava određivanje TEC vrednosti na  putanji između satelita i prijemnika. Prikupljanje podataka izvršeno je u okviru 2022. godine tako da merne sesije obuhvate karakteristične datume u okviru godine kada se očekuju najveća kolebanja u kontekstu sezonskih varijacija., Multi-frequency GNSS satellite signals and their availability enable research in undifferentiated and uncombined models in which a single signal at each frequency is a corresponding independent observation. Such possibilities are reflected by the significant interest in geodetic research as well as in many areas of application of GNSS observation. On the geometric path of the signal between the satellite and the receiver, a significant source of GNSS measurement errors comes from the medium of propagation of electromagnetic waves. Errors attributed to signal propagation are ionospheric and tropospheric signal delay. The mentioned error sources significantly affect the quality of certain pseudorange and, thus, the quality of the receiver's position in the form of three-dimensional coordinates. This paper presents the analysis and determination of the ionospheric delay of GNSS satellite signals based on the determination of Total Electron Content - TEC at five stations (Beograd, Leskovac, Sombor, Zaječar, and Kraljevo) in the territory of the Republic of Serbia. In order to determine TEC values, the software called "GPS-TEC analysis" developed within the Institute for Scientific Research, Boston College, USA was used, which enables the determination of the TEC value on the path between the satellite and the receiver. The data collection was carried out within the year 2022 so that the measurement sessions include characteristic dates when the most significant fluctuations are expected in the context of seasonal variations.",
publisher = "Savez inženjera i tehničara Srbije, Beograd",
journal = "Tehnika",
title = "Doprinos određivanju jonosferskog kašnjenja GNSS satelitskih signala na teritoriji Republike Srbije",
pages = "28-21",
number = "1",
volume = "78",
doi = "10.5937/tehnika2301021P"
}

Petković, D., Brajović, L., Vasilić, V.,& Босиочић, С.. (2023). Doprinos određivanju jonosferskog kašnjenja GNSS satelitskih signala na teritoriji Republike Srbije. in Tehnika
Savez inženjera i tehničara Srbije, Beograd., 78(1), 21-28.
https://doi.org/10.5937/tehnika2301021P

Petković D, Brajović L, Vasilić V, Босиочић С. Doprinos određivanju jonosferskog kašnjenja GNSS satelitskih signala na teritoriji Republike Srbije. in Tehnika. 2023;78(1):21-28.
doi:10.5937/tehnika2301021P .

Petković, Dušan, Brajović, Ljiljana, Vasilić, Violeta, Босиочић, Станислава, "Doprinos određivanju jonosferskog kašnjenja GNSS satelitskih signala na teritoriji Republike Srbije" in Tehnika, 78, no. 1 (2023):21-28,
https://doi.org/10.5937/tehnika2301021P . .

TY  - JOUR
AU  - Mićić, Milica
AU  - Brajović, Ljiljana
AU  - Lazarević, Luka
AU  - Popović, Zdenka
PY  - 2023
UR  - https://grafar.grf.bg.ac.rs/handle/123456789/2814
AB  - Rail inspection research is a substantive topic for the railway industry. Management of rolling contact fatigue rail defects is crucial for transport safety worldwide because uncontrolled development of these defects could cause railway accidents, including derailments. This paper presents the review of non-destructive inspection methods for surface and subsurface rolling contact fatigue defects, with particular emphasis on squat and head checking rail defects. Main types of standard and novel non-destructive inspection methods are presented and described from the aspect of basic characteristics, advantages and disadvantages for its practical application for rails in the track, and possible improvements of equipment and software. The presented review is based on the relevant international researches and review papers. In addition, a combination of inspection methods are presented, which can improve the reliability of defect detection.
PB  - Academic Press
T2  - Mechanical Systems and Signal Processing
T1  - Inspection of RCF rail defects – Review of NDT methods
VL  - 182
DO  - 10.1016/j.ymssp.2022.109568
ER  - 

@article{
author = "Mićić, Milica and Brajović, Ljiljana and Lazarević, Luka and Popović, Zdenka",
year = "2023",
abstract = "Rail inspection research is a substantive topic for the railway industry. Management of rolling contact fatigue rail defects is crucial for transport safety worldwide because uncontrolled development of these defects could cause railway accidents, including derailments. This paper presents the review of non-destructive inspection methods for surface and subsurface rolling contact fatigue defects, with particular emphasis on squat and head checking rail defects. Main types of standard and novel non-destructive inspection methods are presented and described from the aspect of basic characteristics, advantages and disadvantages for its practical application for rails in the track, and possible improvements of equipment and software. The presented review is based on the relevant international researches and review papers. In addition, a combination of inspection methods are presented, which can improve the reliability of defect detection.",
publisher = "Academic Press",
journal = "Mechanical Systems and Signal Processing",
title = "Inspection of RCF rail defects – Review of NDT methods",
volume = "182",
doi = "10.1016/j.ymssp.2022.109568"
}

Mićić, M., Brajović, L., Lazarević, L.,& Popović, Z.. (2023). Inspection of RCF rail defects – Review of NDT methods. in Mechanical Systems and Signal Processing
Academic Press., 182.
https://doi.org/10.1016/j.ymssp.2022.109568

Mićić M, Brajović L, Lazarević L, Popović Z. Inspection of RCF rail defects – Review of NDT methods. in Mechanical Systems and Signal Processing. 2023;182.
doi:10.1016/j.ymssp.2022.109568 .

Mićić, Milica, Brajović, Ljiljana, Lazarević, Luka, Popović, Zdenka, "Inspection of RCF rail defects – Review of NDT methods" in Mechanical Systems and Signal Processing, 182 (2023),
https://doi.org/10.1016/j.ymssp.2022.109568 . .

TY  - CONF
AU  - Vasilić, Violeta
AU  - Brajović, Ljiljana
AU  - Petković, Dušan
AU  - Blagojević, Dragan
PY  - 2023
UR  - https://grafar.grf.bg.ac.rs/handle/123456789/3229
AB  - The propagation of the Global Navigation Satellite System (GNSS) signals through the atmosphere is affected by the electron content in the ionosphere and the air density in the electrically neutral troposphere, thus causing a signal delay and leading to errors in the GNSS observations and the estimated positions. 	Our research has been conducted related to the influence of the tropospheric layer of the Earth's atmosphere on signals at geodetic observation stations in the zenith direction. Since tropospheric refraction cannot be directly estimated, the signal delay has been quantified by applying several developed models. As the lowest layer of the atmosphere, the average height of the troposphere is approximately ten kilometers, and it is variable concerning the latitude of the measuring station and seasonal conditions. The tropospheric delay of the GNSS signal - Zenith Total Delay (ZTD), was analyzed on the examples of three International GNSS Service (IGS) stations at different latitudes. Two epochs in July 2022 and January 2023 for each IGS station are considered regarding seasonal differences in the atmospheric parameters. It was found that at each of the IGS stations, there is an oscillation of the ZTD amplitude with a half-day period. Different patterns were distinguished at each station, depending on the station latitude and epoch, i.e., summer or winter atmospheric conditions. For example, a random walk signal was dominant at the ROAG, San Fernando IGS station.
PB  - Faculty of Civil Engineering, University of Belgrade and Institute of Physics Belgrade, University of Belgrade
C3  - Book of Abstracts and Contributed Papers, International Conference on Recent Trends in Geoscience Research and Applications, Belgrade, October 23–27, 2023
T1  - Tropospheric refraction and its influence through Zenith Total Path Delay at different IGS stations
UR  - https://hdl.handle.net/21.15107/rcub_grafar_3229
ER  - 

@conference{
author = "Vasilić, Violeta and Brajović, Ljiljana and Petković, Dušan and Blagojević, Dragan",
year = "2023",
abstract = "The propagation of the Global Navigation Satellite System (GNSS) signals through the atmosphere is affected by the electron content in the ionosphere and the air density in the electrically neutral troposphere, thus causing a signal delay and leading to errors in the GNSS observations and the estimated positions. 	Our research has been conducted related to the influence of the tropospheric layer of the Earth's atmosphere on signals at geodetic observation stations in the zenith direction. Since tropospheric refraction cannot be directly estimated, the signal delay has been quantified by applying several developed models. As the lowest layer of the atmosphere, the average height of the troposphere is approximately ten kilometers, and it is variable concerning the latitude of the measuring station and seasonal conditions. The tropospheric delay of the GNSS signal - Zenith Total Delay (ZTD), was analyzed on the examples of three International GNSS Service (IGS) stations at different latitudes. Two epochs in July 2022 and January 2023 for each IGS station are considered regarding seasonal differences in the atmospheric parameters. It was found that at each of the IGS stations, there is an oscillation of the ZTD amplitude with a half-day period. Different patterns were distinguished at each station, depending on the station latitude and epoch, i.e., summer or winter atmospheric conditions. For example, a random walk signal was dominant at the ROAG, San Fernando IGS station.",
publisher = "Faculty of Civil Engineering, University of Belgrade and Institute of Physics Belgrade, University of Belgrade",
journal = "Book of Abstracts and Contributed Papers, International Conference on Recent Trends in Geoscience Research and Applications, Belgrade, October 23–27, 2023",
title = "Tropospheric refraction and its influence through Zenith Total Path Delay at different IGS stations",
url = "https://hdl.handle.net/21.15107/rcub_grafar_3229"
}

Vasilić, V., Brajović, L., Petković, D.,& Blagojević, D.. (2023). Tropospheric refraction and its influence through Zenith Total Path Delay at different IGS stations. in Book of Abstracts and Contributed Papers, International Conference on Recent Trends in Geoscience Research and Applications, Belgrade, October 23–27, 2023
Faculty of Civil Engineering, University of Belgrade and Institute of Physics Belgrade, University of Belgrade..
https://hdl.handle.net/21.15107/rcub_grafar_3229

Vasilić V, Brajović L, Petković D, Blagojević D. Tropospheric refraction and its influence through Zenith Total Path Delay at different IGS stations. in Book of Abstracts and Contributed Papers, International Conference on Recent Trends in Geoscience Research and Applications, Belgrade, October 23–27, 2023. 2023;.
https://hdl.handle.net/21.15107/rcub_grafar_3229 .

Vasilić, Violeta, Brajović, Ljiljana, Petković, Dušan, Blagojević, Dragan, "Tropospheric refraction and its influence through Zenith Total Path Delay at different IGS stations" in Book of Abstracts and Contributed Papers, International Conference on Recent Trends in Geoscience Research and Applications, Belgrade, October 23–27, 2023 (2023),
https://hdl.handle.net/21.15107/rcub_grafar_3229 .

TY  - GEN
AU  - Brajović, Ljiljana
PY  - 2022
UR  - https://grafar.grf.bg.ac.rs/handle/123456789/3295
AB  - Primene fiberoptičkih senzora (FOS) u oblasti građevinarsta se više od dvadeset godina intenzivno proučavaju za potrebe praćenja stanja mostova, hidrotehničkih brana, tunela, zgrada, kao i putne i železničke infrastructure. Posebno pogodni tipovi FOS za ove namene su senzori sa ugrađenim Bragovim rešetkama i distributivni FOS, a koji su dostupni sada i u obliku različitih komercijalizovanih senzorskih sistema. U ovom radu su objašnjeni principi rada, trenutno dostignut nivo razvoja i merne karakteristika različitih tipova FOS i prikazani su primeri njihove primene u različitim oblastima građevinarstva. Diskutovane su njihove prednosti i ograničenja za primene u građevinarstvu kao i mogućnosti daljih poboljšanja.
T2  - Zbornik radova Kongresa metrologa 2022 objavljen u elektronskoj formi i javno dostupan
T1  - Senzori na bazi optičkih vlakana i njihove primene u građevinarstvu
UR  - https://hdl.handle.net/21.15107/rcub_grafar_3295
ER  - 

@misc{
author = "Brajović, Ljiljana",
year = "2022",
abstract = "Primene fiberoptičkih senzora (FOS) u oblasti građevinarsta se više od dvadeset godina intenzivno proučavaju za potrebe praćenja stanja mostova, hidrotehničkih brana, tunela, zgrada, kao i putne i železničke infrastructure. Posebno pogodni tipovi FOS za ove namene su senzori sa ugrađenim Bragovim rešetkama i distributivni FOS, a koji su dostupni sada i u obliku različitih komercijalizovanih senzorskih sistema. U ovom radu su objašnjeni principi rada, trenutno dostignut nivo razvoja i merne karakteristika različitih tipova FOS i prikazani su primeri njihove primene u različitim oblastima građevinarstva. Diskutovane su njihove prednosti i ograničenja za primene u građevinarstvu kao i mogućnosti daljih poboljšanja.",
journal = "Zbornik radova Kongresa metrologa 2022 objavljen u elektronskoj formi i javno dostupan",
title = "Senzori na bazi optičkih vlakana i njihove primene u građevinarstvu",
url = "https://hdl.handle.net/21.15107/rcub_grafar_3295"
}

Brajović, L.. (2022). Senzori na bazi optičkih vlakana i njihove primene u građevinarstvu. in Zbornik radova Kongresa metrologa 2022 objavljen u elektronskoj formi i javno dostupan.
https://hdl.handle.net/21.15107/rcub_grafar_3295

Brajović L. Senzori na bazi optičkih vlakana i njihove primene u građevinarstvu. in Zbornik radova Kongresa metrologa 2022 objavljen u elektronskoj formi i javno dostupan. 2022;.
https://hdl.handle.net/21.15107/rcub_grafar_3295 .

Brajović, Ljiljana, "Senzori na bazi optičkih vlakana i njihove primene u građevinarstvu" in Zbornik radova Kongresa metrologa 2022 objavljen u elektronskoj formi i javno dostupan (2022),
https://hdl.handle.net/21.15107/rcub_grafar_3295 .

TY  - CONF
AU  - Malović, Miodrag
AU  - Brajović, Ljiljana
AU  - Šekara, Tomislav
PY  - 2022
UR  - https://grafar.grf.bg.ac.rs/handle/123456789/2939
AB  - Oscilatorna kola su neizbežni deo praktično svih
elektronskih uređaja. Najčešće se koriste kola na bazi kvarcnih
kristala. Prikazan je proces proizvodnje i princip rada kvarcnih
oscilatora, kao i podele kristala i oscilatornih kola. Analizirane
su metode kvantitativnog opisivanja greške odnosno
nestabilnosti frekvencije. Efekti koji utiču na promene
frekvencije su klasifikovani po fizičkom poreklu i vremenskom
periodu u kom se dešavaju.
PB  - Друштво за ЕТРАН, Београд и Академска мисао, Београд
C3  - ЗБОРНИК РАДОВА  IX међународне конференције ИцЕТРАН   и LXVI конференције ЕТРАН,   Нови Пазар 6 ‐ 9. јуна 2022. године
T1  - Stabilnost frekvencije kvarcnih oscilatora
SP  - SSFO1.5
UR  - https://hdl.handle.net/21.15107/rcub_grafar_2939
ER  - 

@conference{
author = "Malović, Miodrag and Brajović, Ljiljana and Šekara, Tomislav",
year = "2022",
abstract = "Oscilatorna kola su neizbežni deo praktično svih
elektronskih uređaja. Najčešće se koriste kola na bazi kvarcnih
kristala. Prikazan je proces proizvodnje i princip rada kvarcnih
oscilatora, kao i podele kristala i oscilatornih kola. Analizirane
su metode kvantitativnog opisivanja greške odnosno
nestabilnosti frekvencije. Efekti koji utiču na promene
frekvencije su klasifikovani po fizičkom poreklu i vremenskom
periodu u kom se dešavaju.",
publisher = "Друштво за ЕТРАН, Београд и Академска мисао, Београд",
journal = "ЗБОРНИК РАДОВА  IX међународне конференције ИцЕТРАН   и LXVI конференције ЕТРАН,   Нови Пазар 6 ‐ 9. јуна 2022. године",
title = "Stabilnost frekvencije kvarcnih oscilatora",
pages = "SSFO1.5",
url = "https://hdl.handle.net/21.15107/rcub_grafar_2939"
}

Malović, M., Brajović, L.,& Šekara, T.. (2022). Stabilnost frekvencije kvarcnih oscilatora. in ЗБОРНИК РАДОВА  IX међународне конференције ИцЕТРАН   и LXVI конференције ЕТРАН,   Нови Пазар 6 ‐ 9. јуна 2022. године
Друштво за ЕТРАН, Београд и Академска мисао, Београд., SSFO1.5.
https://hdl.handle.net/21.15107/rcub_grafar_2939

Malović M, Brajović L, Šekara T. Stabilnost frekvencije kvarcnih oscilatora. in ЗБОРНИК РАДОВА  IX међународне конференције ИцЕТРАН   и LXVI конференције ЕТРАН,   Нови Пазар 6 ‐ 9. јуна 2022. године. 2022;:SSFO1.5.
https://hdl.handle.net/21.15107/rcub_grafar_2939 .

Malović, Miodrag, Brajović, Ljiljana, Šekara, Tomislav, "Stabilnost frekvencije kvarcnih oscilatora" in ЗБОРНИК РАДОВА  IX међународне конференције ИцЕТРАН   и LXVI конференције ЕТРАН,   Нови Пазар 6 ‐ 9. јуна 2022. године (2022):SSFO1.5,
https://hdl.handle.net/21.15107/rcub_grafar_2939 .

TY  - JOUR
AU  - Popović, Zdenka
AU  - Lazarević, Luka
AU  - Mićić, Milica
AU  - Brajović, Ljiljana
PY  - 2022
UR  - https://grafar.grf.bg.ac.rs/handle/123456789/2815
AB  - The paper presents a brief review of the rail defect coding systems, which were recommended by the International Union of Railways during the period from 1959 to today. The recommended classification and numbering of RCF rail defects, defined in the document IRS 70712 from 2018, were critically analysed. In addition, harmonisation of European standards and IRS 70712 was found necessary by the authors. The paper points out that appropriate attention was paid neither to the combination of several types of RCF rail defects nor to the occurrence of these defects in the sensitive track zones such as switches, crossings, expansion joints, and insulated rail joints. Authors propose that Infrastructure Managers should supplement the Handbook of rail defects with RCF defects that occur on the railway network under their control. Moreover, the authors present the experience regarding RCF defects on the Serbian railway network.
PB  - Elsevier B.V.
T2  - Transportation Research Procedia
T1  - Critical analysis of RCF rail defects classification
VL  - 63
DO  - 10.1016/j.trpro.2022.06.294
ER  - 

@article{
author = "Popović, Zdenka and Lazarević, Luka and Mićić, Milica and Brajović, Ljiljana",
year = "2022",
abstract = "The paper presents a brief review of the rail defect coding systems, which were recommended by the International Union of Railways during the period from 1959 to today. The recommended classification and numbering of RCF rail defects, defined in the document IRS 70712 from 2018, were critically analysed. In addition, harmonisation of European standards and IRS 70712 was found necessary by the authors. The paper points out that appropriate attention was paid neither to the combination of several types of RCF rail defects nor to the occurrence of these defects in the sensitive track zones such as switches, crossings, expansion joints, and insulated rail joints. Authors propose that Infrastructure Managers should supplement the Handbook of rail defects with RCF defects that occur on the railway network under their control. Moreover, the authors present the experience regarding RCF defects on the Serbian railway network.",
publisher = "Elsevier B.V.",
journal = "Transportation Research Procedia",
title = "Critical analysis of RCF rail defects classification",
volume = "63",
doi = "10.1016/j.trpro.2022.06.294"
}

Popović, Z., Lazarević, L., Mićić, M.,& Brajović, L.. (2022). Critical analysis of RCF rail defects classification. in Transportation Research Procedia
Elsevier B.V.., 63.
https://doi.org/10.1016/j.trpro.2022.06.294

Popović Z, Lazarević L, Mićić M, Brajović L. Critical analysis of RCF rail defects classification. in Transportation Research Procedia. 2022;63.
doi:10.1016/j.trpro.2022.06.294 .

Popović, Zdenka, Lazarević, Luka, Mićić, Milica, Brajović, Ljiljana, "Critical analysis of RCF rail defects classification" in Transportation Research Procedia, 63 (2022),
https://doi.org/10.1016/j.trpro.2022.06.294 . .

TY  - CONF
AU  - Martinenko, Anastasija
AU  - Brajović, Ljiljana
AU  - Malović, Miodrag
PY  - 2022
UR  - https://grafar.grf.bg.ac.rs/handle/123456789/2680
AB  - In this paper, the possibility of applying Kirchhoff 's scalar approximation model for determining the backscattering coefficient from rough surfaces is investigated. Surfaces of dielectric and metallic materials, which have low roughness are considered. Based on the roughness parameters and electrical properties of these materials, the backscattering coefficient is modelled as a function of 
the incident angle of electromagnetic radiation used in laser scanning. It was represented that the type of scattering and the range of backscattering radiation angles, in the case of seemingly smooth surfaces, vary significantly when the roughness parameters change.
PB  - University of Banja Luka, Faculty of Architecture, Civil Engineering and Geodesy
C3  - STEPGRAD2022
T1  - Influence of material surface roughness on backscattering in laser scanning
DO  - 10.7251/STP2215487M
ER  - 

@conference{
author = "Martinenko, Anastasija and Brajović, Ljiljana and Malović, Miodrag",
year = "2022",
abstract = "In this paper, the possibility of applying Kirchhoff 's scalar approximation model for determining the backscattering coefficient from rough surfaces is investigated. Surfaces of dielectric and metallic materials, which have low roughness are considered. Based on the roughness parameters and electrical properties of these materials, the backscattering coefficient is modelled as a function of 
the incident angle of electromagnetic radiation used in laser scanning. It was represented that the type of scattering and the range of backscattering radiation angles, in the case of seemingly smooth surfaces, vary significantly when the roughness parameters change.",
publisher = "University of Banja Luka, Faculty of Architecture, Civil Engineering and Geodesy",
journal = "STEPGRAD2022",
title = "Influence of material surface roughness on backscattering in laser scanning",
doi = "10.7251/STP2215487M"
}

Martinenko, A., Brajović, L.,& Malović, M.. (2022). Influence of material surface roughness on backscattering in laser scanning. in STEPGRAD2022
University of Banja Luka, Faculty of Architecture, Civil Engineering and Geodesy..
https://doi.org/10.7251/STP2215487M

Martinenko A, Brajović L, Malović M. Influence of material surface roughness on backscattering in laser scanning. in STEPGRAD2022. 2022;.
doi:10.7251/STP2215487M .

Martinenko, Anastasija, Brajović, Ljiljana, Malović, Miodrag, "Influence of material surface roughness on backscattering in laser scanning" in STEPGRAD2022 (2022),
https://doi.org/10.7251/STP2215487M . .

TY  - CONF
AU  - Praštalo, Petar
AU  - Brajović, Ljiljana
AU  - Prodanović, Dušan
PY  - 2022
UR  - https://grafar.grf.bg.ac.rs/handle/123456789/2823
AB  - Soil moisture is one of crucial parameters in modeling and analysis of groundwater flow.
Measurement of soil water dynamics improves the understanding of processes and is vital for good
groundwater flow model calibration. Determining soil moisture change during time by laboratory
methods, as an integral part of practical classes, requires significant material and financial resources.
Nowadays, relatively cheap sensors for measuring soil moisture are available. They could be
combined with affordable data loggers to speed up the measurement procedure and to reduce cost
price. In this paper, the possibility of using these sensors for measuring soil moisture and their usage
for the educational experimental exercises in a field of hydraulic engineering was investigated. The
paper first presents the procedure of sensor calibration for four different sensors used in two types
of soil, and then their usage in a simple hydraulic engineering experiment.
PB  - University of Banja LukaFaculty of Architecture, Civil Engineering and Geodesy
C3  - No. 15 (2022): PROCEEDINGS of International conference on Contemporary Theory and Practice in Construction XV
T1  - Using of low cost moisture sensors in laboratory experiments
DO  - 10.7251/STP2215530P
ER  - 

@conference{
author = "Praštalo, Petar and Brajović, Ljiljana and Prodanović, Dušan",
year = "2022",
abstract = "Soil moisture is one of crucial parameters in modeling and analysis of groundwater flow.
Measurement of soil water dynamics improves the understanding of processes and is vital for good
groundwater flow model calibration. Determining soil moisture change during time by laboratory
methods, as an integral part of practical classes, requires significant material and financial resources.
Nowadays, relatively cheap sensors for measuring soil moisture are available. They could be
combined with affordable data loggers to speed up the measurement procedure and to reduce cost
price. In this paper, the possibility of using these sensors for measuring soil moisture and their usage
for the educational experimental exercises in a field of hydraulic engineering was investigated. The
paper first presents the procedure of sensor calibration for four different sensors used in two types
of soil, and then their usage in a simple hydraulic engineering experiment.",
publisher = "University of Banja LukaFaculty of Architecture, Civil Engineering and Geodesy",
journal = "No. 15 (2022): PROCEEDINGS of International conference on Contemporary Theory and Practice in Construction XV",
title = "Using of low cost moisture sensors in laboratory experiments",
doi = "10.7251/STP2215530P"
}

Praštalo, P., Brajović, L.,& Prodanović, D.. (2022). Using of low cost moisture sensors in laboratory experiments. in No. 15 (2022): PROCEEDINGS of International conference on Contemporary Theory and Practice in Construction XV
University of Banja LukaFaculty of Architecture, Civil Engineering and Geodesy..
https://doi.org/10.7251/STP2215530P

Praštalo P, Brajović L, Prodanović D. Using of low cost moisture sensors in laboratory experiments. in No. 15 (2022): PROCEEDINGS of International conference on Contemporary Theory and Practice in Construction XV. 2022;.
doi:10.7251/STP2215530P .

Praštalo, Petar, Brajović, Ljiljana, Prodanović, Dušan, "Using of low cost moisture sensors in laboratory experiments" in No. 15 (2022): PROCEEDINGS of International conference on Contemporary Theory and Practice in Construction XV (2022),
https://doi.org/10.7251/STP2215530P . .

TY  - CONF
AU  - Vasilić, Violeta
AU  - Brajović, Ljiljana
PY  - 2022
UR  - https://grafar.grf.bg.ac.rs/handle/123456789/2844
AB  - The electro-optical distance measurement (EDM) instruments are widely used not only in geodesy but also in almost all engineering disciplines and related projects. High accuracy length measurements are required especially for different engineering works in urban areas. The paper will present the sources of errors which originate from the atmospheric conditions present in the process of measuring lengths with electro-optical light wave EDM.  First, the working principle based on phase difference measurements and the basic components of EDM are described. 
Atmospheric influence parameters, temperature, atmospheric pressure and air humidity, their impact on the EDM measurements and the formulae recommended by IAG Resolution 3 adopted at the XXIIth General Assembly for the calculating the atmospheric influences are presented. 
The atmospheric influence parameters were treated as well-understood effect from a metrological point of view in according with the GUM - Part 6: Developing and using measurement models. Sensors with an appropriate resolution for measure temperature, atmospheric pressure and air humidity are used in this research.
The first velocity correction estimate is based in part on the a priori known wavelength of the oscillator of the electro-optical EDM instrument and in part on the measured atmospheric parameters. Depending on the frequency bandwidth, as well as, the values of the measured lengths, the group refractive index of air and the first velocity correction is calculated for two EDM instruments Wild DI 20 and Leica TS30.
The values of errors in distance measurements both for the shorter distances up to 500 m and longer distances up to 2 km in the case that temperature, pressure and air humidity influence are not accurately represented in real conditions are given and discussed.
It is shown that first velocity corrections increase with temperature for all measured distances for both types of EDM instruments. Based on the comparison of correction errors for Wild DI 20 and Leica TS 30 instruments, it was concluded that the correction errors in both cases of measurement at lower and higher temperatures than nominal are less for the Wild DI 20 instrument.
PB  - International Federation of Surveyors, FIG
T1  - The impact of the Atmospheric Parameters at Electrooptical Distance Measurements
UR  - https://hdl.handle.net/21.15107/rcub_grafar_2844
ER  - 

@conference{
author = "Vasilić, Violeta and Brajović, Ljiljana",
year = "2022",
abstract = "The electro-optical distance measurement (EDM) instruments are widely used not only in geodesy but also in almost all engineering disciplines and related projects. High accuracy length measurements are required especially for different engineering works in urban areas. The paper will present the sources of errors which originate from the atmospheric conditions present in the process of measuring lengths with electro-optical light wave EDM.  First, the working principle based on phase difference measurements and the basic components of EDM are described. 
Atmospheric influence parameters, temperature, atmospheric pressure and air humidity, their impact on the EDM measurements and the formulae recommended by IAG Resolution 3 adopted at the XXIIth General Assembly for the calculating the atmospheric influences are presented. 
The atmospheric influence parameters were treated as well-understood effect from a metrological point of view in according with the GUM - Part 6: Developing and using measurement models. Sensors with an appropriate resolution for measure temperature, atmospheric pressure and air humidity are used in this research.
The first velocity correction estimate is based in part on the a priori known wavelength of the oscillator of the electro-optical EDM instrument and in part on the measured atmospheric parameters. Depending on the frequency bandwidth, as well as, the values of the measured lengths, the group refractive index of air and the first velocity correction is calculated for two EDM instruments Wild DI 20 and Leica TS30.
The values of errors in distance measurements both for the shorter distances up to 500 m and longer distances up to 2 km in the case that temperature, pressure and air humidity influence are not accurately represented in real conditions are given and discussed.
It is shown that first velocity corrections increase with temperature for all measured distances for both types of EDM instruments. Based on the comparison of correction errors for Wild DI 20 and Leica TS 30 instruments, it was concluded that the correction errors in both cases of measurement at lower and higher temperatures than nominal are less for the Wild DI 20 instrument.",
publisher = "International Federation of Surveyors, FIG",
title = "The impact of the Atmospheric Parameters at Electrooptical Distance Measurements",
url = "https://hdl.handle.net/21.15107/rcub_grafar_2844"
}

Vasilić, V.,& Brajović, L.. (2022). The impact of the Atmospheric Parameters at Electrooptical Distance Measurements. 
International Federation of Surveyors, FIG..
https://hdl.handle.net/21.15107/rcub_grafar_2844

Vasilić V, Brajović L. The impact of the Atmospheric Parameters at Electrooptical Distance Measurements. 2022;.
https://hdl.handle.net/21.15107/rcub_grafar_2844 .

Vasilić, Violeta, Brajović, Ljiljana, "The impact of the Atmospheric Parameters at Electrooptical Distance Measurements" (2022),
https://hdl.handle.net/21.15107/rcub_grafar_2844 .

TY  - CONF
AU  - Brajović, Ljiljana
AU  - Malović, Miodrag
PY  - 2022
UR  - https://grafar.grf.bg.ac.rs/handle/123456789/2822
AB  - Gravity satellite missions measurement data are primarily intended for use in
the estimation of an accurate model of Earth’s gravity field. The satellites’ almost
circular orbits with polar or near-polar inclination of the orbital planes, and low
altitude (between 250 and 500 km), enable almost full coverage of the globe. Orbit
tracking by precise high orbiting navigation satellite system provides the data about
three-dimensional satellite position and its deviations. Precision accelerometers on
the satellites extend the ability to monitor non-gravitational forces acting on them
continuously. One of these forces, atmospheric drag along orbits, can be derived
from the orbit track positions and their derivatives, and also from the precise
accelerometer measurements, so it can be used for atmospheric mass density
determination. On the other hand, the density of the atmosphere and its main
constituents can be derived from the spectroscopic measurements. One of the
examples is thermospheric mass density determination using neutral mass
spectrometers on earlier satellite missions. Measurement of the Earth’s far
ultraviolet (FUV) dayglow is used to infer number density profiles of N2, O, and
O2. Combination of accelerometers measurements and spectroscopic data is the
foundation of two widely used empirical models of thermospheric mass density.
This contribution describes the basic measurements on gravity satellite missions
and atmospheric drag estimation, gives the comparison and combination of
obtained data with spectrometric measurements of atmospheric density, and lists
potential improvements using the data from the recently launched satellite gravity
missions.
PB  - Institute of Physics Belgrade, Pregrevica 118, 11080 Belgrade Serbia
C3  - BOOK OF ABSTRACTS of IV Meeting on Astrophysical Spectroscopy - A&M DATA - Atmosphere May 30 to June 2, 2022, Fruška Gora, Serbia
T1  - Gravity satellite missions measurement data for atmospheric density estimation
UR  - https://hdl.handle.net/21.15107/rcub_grafar_2822
ER  - 

@conference{
author = "Brajović, Ljiljana and Malović, Miodrag",
year = "2022",
abstract = "Gravity satellite missions measurement data are primarily intended for use in
the estimation of an accurate model of Earth’s gravity field. The satellites’ almost
circular orbits with polar or near-polar inclination of the orbital planes, and low
altitude (between 250 and 500 km), enable almost full coverage of the globe. Orbit
tracking by precise high orbiting navigation satellite system provides the data about
three-dimensional satellite position and its deviations. Precision accelerometers on
the satellites extend the ability to monitor non-gravitational forces acting on them
continuously. One of these forces, atmospheric drag along orbits, can be derived
from the orbit track positions and their derivatives, and also from the precise
accelerometer measurements, so it can be used for atmospheric mass density
determination. On the other hand, the density of the atmosphere and its main
constituents can be derived from the spectroscopic measurements. One of the
examples is thermospheric mass density determination using neutral mass
spectrometers on earlier satellite missions. Measurement of the Earth’s far
ultraviolet (FUV) dayglow is used to infer number density profiles of N2, O, and
O2. Combination of accelerometers measurements and spectroscopic data is the
foundation of two widely used empirical models of thermospheric mass density.
This contribution describes the basic measurements on gravity satellite missions
and atmospheric drag estimation, gives the comparison and combination of
obtained data with spectrometric measurements of atmospheric density, and lists
potential improvements using the data from the recently launched satellite gravity
missions.",
publisher = "Institute of Physics Belgrade, Pregrevica 118, 11080 Belgrade Serbia",
journal = "BOOK OF ABSTRACTS of IV Meeting on Astrophysical Spectroscopy - A&M DATA - Atmosphere May 30 to June 2, 2022, Fruška Gora, Serbia",
title = "Gravity satellite missions measurement data for atmospheric density estimation",
url = "https://hdl.handle.net/21.15107/rcub_grafar_2822"
}

Brajović, L.,& Malović, M.. (2022). Gravity satellite missions measurement data for atmospheric density estimation. in BOOK OF ABSTRACTS of IV Meeting on Astrophysical Spectroscopy - A&M DATA - Atmosphere May 30 to June 2, 2022, Fruška Gora, Serbia
Institute of Physics Belgrade, Pregrevica 118, 11080 Belgrade Serbia..
https://hdl.handle.net/21.15107/rcub_grafar_2822

Brajović L, Malović M. Gravity satellite missions measurement data for atmospheric density estimation. in BOOK OF ABSTRACTS of IV Meeting on Astrophysical Spectroscopy - A&M DATA - Atmosphere May 30 to June 2, 2022, Fruška Gora, Serbia. 2022;.
https://hdl.handle.net/21.15107/rcub_grafar_2822 .

Brajović, Ljiljana, Malović, Miodrag, "Gravity satellite missions measurement data for atmospheric density estimation" in BOOK OF ABSTRACTS of IV Meeting on Astrophysical Spectroscopy - A&M DATA - Atmosphere May 30 to June 2, 2022, Fruška Gora, Serbia (2022),
https://hdl.handle.net/21.15107/rcub_grafar_2822 .

TY  - JOUR
AU  - Mirković, Nikola
AU  - Brajović, Ljiljana
AU  - Popović, Zdenka
AU  - Todorović, Goran
AU  - Lazarević, Luka
AU  - Petrović, Miloš
PY  - 2021
UR  - https://grafar.grf.bg.ac.rs/handle/123456789/2312
AB  - The main aim of conducted research is determination of temperature stresses due to the uneven temperature
distribution in CWR. This paper presents a methodology for determination of temperature stresses
in CWR based on (1) measurement system developed by the authors for measurement of rail surface temperatures,
and (2) coupled transient thermal-stress analysis for simulation of rail temperature field and
corresponding stresses. The main advantages of the proposed methodology are high sensitivity to the
small temperature variations, taking into account the effect of thermal inertia, as well as measurement
of single input parameter - rail surface temperature. The obtained experimental results showed lower rail
temperatures in sleeper zones and rail foot along CWR, which emphasize the effect of heat transfer
between rail and sleeper, as well as rail foot and ballast. These effects of heat transfer directly influence
the decrease of temperature stresses in the mentioned zones of CWR. The maximum values of simulated
temperature stresses are up to 16% less in the centre of gravity of railhead, up to 9.8% less in the centre of
gravity of rail foot, and up to 0.2% less in the centre of gravity of rail web, compared to the common engineering
calculation. In addition, the maximum value of simulated temperature force, based on temperature
stresses in the rail cross-section, was up to 5.3% less than the value obtained in the common
engineering calculation.
PB  - Elsevier
T2  - Construction and Building Materials
T1  - Determination of temperature stresses in CWR based on measured rail surface temperatures
IS  - 122713
VL  - 284
DO  - 10.1016/j.conbuildmat.2021.122713
ER  - 

@article{
author = "Mirković, Nikola and Brajović, Ljiljana and Popović, Zdenka and Todorović, Goran and Lazarević, Luka and Petrović, Miloš",
year = "2021",
abstract = "The main aim of conducted research is determination of temperature stresses due to the uneven temperature
distribution in CWR. This paper presents a methodology for determination of temperature stresses
in CWR based on (1) measurement system developed by the authors for measurement of rail surface temperatures,
and (2) coupled transient thermal-stress analysis for simulation of rail temperature field and
corresponding stresses. The main advantages of the proposed methodology are high sensitivity to the
small temperature variations, taking into account the effect of thermal inertia, as well as measurement
of single input parameter - rail surface temperature. The obtained experimental results showed lower rail
temperatures in sleeper zones and rail foot along CWR, which emphasize the effect of heat transfer
between rail and sleeper, as well as rail foot and ballast. These effects of heat transfer directly influence
the decrease of temperature stresses in the mentioned zones of CWR. The maximum values of simulated
temperature stresses are up to 16% less in the centre of gravity of railhead, up to 9.8% less in the centre of
gravity of rail foot, and up to 0.2% less in the centre of gravity of rail web, compared to the common engineering
calculation. In addition, the maximum value of simulated temperature force, based on temperature
stresses in the rail cross-section, was up to 5.3% less than the value obtained in the common
engineering calculation.",
publisher = "Elsevier",
journal = "Construction and Building Materials",
title = "Determination of temperature stresses in CWR based on measured rail surface temperatures",
number = "122713",
volume = "284",
doi = "10.1016/j.conbuildmat.2021.122713"
}

Mirković, N., Brajović, L., Popović, Z., Todorović, G., Lazarević, L.,& Petrović, M.. (2021). Determination of temperature stresses in CWR based on measured rail surface temperatures. in Construction and Building Materials
Elsevier., 284(122713).
https://doi.org/10.1016/j.conbuildmat.2021.122713

Mirković N, Brajović L, Popović Z, Todorović G, Lazarević L, Petrović M. Determination of temperature stresses in CWR based on measured rail surface temperatures. in Construction and Building Materials. 2021;284(122713).
doi:10.1016/j.conbuildmat.2021.122713 .

Mirković, Nikola, Brajović, Ljiljana, Popović, Zdenka, Todorović, Goran, Lazarević, Luka, Petrović, Miloš, "Determination of temperature stresses in CWR based on measured rail surface temperatures" in Construction and Building Materials, 284, no. 122713 (2021),
https://doi.org/10.1016/j.conbuildmat.2021.122713 . .

TY  - JOUR
AU  - Popović, Zdenka
AU  - Lazarević, Luka
AU  - Mićić, Milica
AU  - Brajović, Ljiljana
PY  - 2021
UR  - https://grafar.grf.bg.ac.rs/handle/123456789/2469
AB  - Šinski defekti usled zamora čelika pri kotrljanju točkova dobili su značajno mesto u Priručniku za
šinske defekte (Handbook of Rail Defects) u okviru UIC Code 712 iz 2002. godine. U radu je prikazan sistem za kodiranje i klasifikaciju šinskih defekata prema UIC preporuci IRS 70712 iz 2018. godine. Prikazana klasifikacija još uvek ne obuhvata sve poznate defekte usled zamora šinskog čelika pri kotrljanju (npr. stud i belgrospi defekti). Preporučuje se da Upravljač infrastrukture dopuni Priručnik za šinske defekte tipovima defekata koje uočava na mreži kojom upravlja. Autori daju preporuku koje podatke treba da sadrži baza šinskih defekata, kako bi se pratio razvoj defekata, preduzete mere i njihova efikasnost i kako bi se omogućila razmena statističkih podataka o defektima na međunarodnom nivou.
PB  - Savez inženjera i tehničara Srbije
T2  - Tehnika
T1  - Kodiranje šinskih defekata prema IRS 70712
EP  - 564
IS  - 5
SP  - 557
VL  - 75
DO  - 10.5937/tehnika2105557P
ER  - 

@article{
author = "Popović, Zdenka and Lazarević, Luka and Mićić, Milica and Brajović, Ljiljana",
year = "2021",
abstract = "Šinski defekti usled zamora čelika pri kotrljanju točkova dobili su značajno mesto u Priručniku za
šinske defekte (Handbook of Rail Defects) u okviru UIC Code 712 iz 2002. godine. U radu je prikazan sistem za kodiranje i klasifikaciju šinskih defekata prema UIC preporuci IRS 70712 iz 2018. godine. Prikazana klasifikacija još uvek ne obuhvata sve poznate defekte usled zamora šinskog čelika pri kotrljanju (npr. stud i belgrospi defekti). Preporučuje se da Upravljač infrastrukture dopuni Priručnik za šinske defekte tipovima defekata koje uočava na mreži kojom upravlja. Autori daju preporuku koje podatke treba da sadrži baza šinskih defekata, kako bi se pratio razvoj defekata, preduzete mere i njihova efikasnost i kako bi se omogućila razmena statističkih podataka o defektima na međunarodnom nivou.",
publisher = "Savez inženjera i tehničara Srbije",
journal = "Tehnika",
title = "Kodiranje šinskih defekata prema IRS 70712",
pages = "564-557",
number = "5",
volume = "75",
doi = "10.5937/tehnika2105557P"
}

Popović, Z., Lazarević, L., Mićić, M.,& Brajović, L.. (2021). Kodiranje šinskih defekata prema IRS 70712. in Tehnika
Savez inženjera i tehničara Srbije., 75(5), 557-564.
https://doi.org/10.5937/tehnika2105557P

Popović Z, Lazarević L, Mićić M, Brajović L. Kodiranje šinskih defekata prema IRS 70712. in Tehnika. 2021;75(5):557-564.
doi:10.5937/tehnika2105557P .

Popović, Zdenka, Lazarević, Luka, Mićić, Milica, Brajović, Ljiljana, "Kodiranje šinskih defekata prema IRS 70712" in Tehnika, 75, no. 5 (2021):557-564,
https://doi.org/10.5937/tehnika2105557P . .

TY  - JOUR
AU  - Naod, Sofija
AU  - Odalović, Oleg
AU  - Brajović, Ljiljana
AU  - Savanović, Rajko
PY  - 2021
UR  - https://grafar.grf.bg.ac.rs/handle/123456789/2286
AB  - Imperial hegemony established by the Habsburg Monarchy relied upon proper mapping during its conquests. The need for the development of geodesy and establishing reference frames was important. Until the end of the First World War, Vojvodina belonged to the Austrian-Hungarian Empire, so all of its surveys were carried out as part of many organized land surveys in the Monarchy. Today, more than 100 years after Vojvodina became the Autonomous Province of Serbia, the network developed by the Monarchy and cadastral plans from that period are still in use. In this paper, in addition to a historical overview of military and cadastral surveys in Vojvodina, we will show data that have historical significance and are available on the Internet and in historical archives. We will also emphasize how the maps available in historical archives of the neighbouring countries could have been used to set up Serbian national spatial data infrastructure.
T2  - Survey Review
T1  - History of geodetic works in Vojvodina (Northern Serbia) and use of old maps in Serbian national spatial data infrastructure
DO  - 10.1080/00396265.2021.1886546
ER  - 

@article{
author = "Naod, Sofija and Odalović, Oleg and Brajović, Ljiljana and Savanović, Rajko",
year = "2021",
abstract = "Imperial hegemony established by the Habsburg Monarchy relied upon proper mapping during its conquests. The need for the development of geodesy and establishing reference frames was important. Until the end of the First World War, Vojvodina belonged to the Austrian-Hungarian Empire, so all of its surveys were carried out as part of many organized land surveys in the Monarchy. Today, more than 100 years after Vojvodina became the Autonomous Province of Serbia, the network developed by the Monarchy and cadastral plans from that period are still in use. In this paper, in addition to a historical overview of military and cadastral surveys in Vojvodina, we will show data that have historical significance and are available on the Internet and in historical archives. We will also emphasize how the maps available in historical archives of the neighbouring countries could have been used to set up Serbian national spatial data infrastructure.",
journal = "Survey Review",
title = "History of geodetic works in Vojvodina (Northern Serbia) and use of old maps in Serbian national spatial data infrastructure",
doi = "10.1080/00396265.2021.1886546"
}

Naod, S., Odalović, O., Brajović, L.,& Savanović, R.. (2021). History of geodetic works in Vojvodina (Northern Serbia) and use of old maps in Serbian national spatial data infrastructure. in Survey Review.
https://doi.org/10.1080/00396265.2021.1886546

Naod S, Odalović O, Brajović L, Savanović R. History of geodetic works in Vojvodina (Northern Serbia) and use of old maps in Serbian national spatial data infrastructure. in Survey Review. 2021;.
doi:10.1080/00396265.2021.1886546 .

Naod, Sofija, Odalović, Oleg, Brajović, Ljiljana, Savanović, Rajko, "History of geodetic works in Vojvodina (Northern Serbia) and use of old maps in Serbian national spatial data infrastructure" in Survey Review (2021),
https://doi.org/10.1080/00396265.2021.1886546 . .

TY  - JOUR
AU  - Popović, Zdenka
AU  - Mirković, Nikola
AU  - Brajović, Ljiljana
AU  - Rakić, Dragan
AU  - Lazarević, Luka
AU  - Petričević, Slobodan
PY  - 2020
UR  - https://grafar.grf.bg.ac.rs/handle/123456789/2571
AB  - The railway track with continuously welded rails is an essential part of
the modern railway superstructure around the world. Calculation of the temperature
stresses in continuously welded rails has great significance for the planning
of maintenance activities in order to maintain traffic safety (risk of derailment due
to either rail break, or track buckling). This paper presents the finite element model
for calculation of rail stresses and displacements due to the temperature changes,
which was developed by the authors. The monitoring of the track sections, which
are significant regarding traffic safety, was suggested in this paper.
PB  - Springer, Cham
T2  - Advances in Intelligent Systems and Computing
T1  - Temperature Stresses in CWR – Experience of Serbian Railways
VL  - 1115
DO  - 10.1007/978-3-030-37916-2_81
ER  - 

@article{
author = "Popović, Zdenka and Mirković, Nikola and Brajović, Ljiljana and Rakić, Dragan and Lazarević, Luka and Petričević, Slobodan",
year = "2020",
abstract = "The railway track with continuously welded rails is an essential part of
the modern railway superstructure around the world. Calculation of the temperature
stresses in continuously welded rails has great significance for the planning
of maintenance activities in order to maintain traffic safety (risk of derailment due
to either rail break, or track buckling). This paper presents the finite element model
for calculation of rail stresses and displacements due to the temperature changes,
which was developed by the authors. The monitoring of the track sections, which
are significant regarding traffic safety, was suggested in this paper.",
publisher = "Springer, Cham",
journal = "Advances in Intelligent Systems and Computing",
title = "Temperature Stresses in CWR – Experience of Serbian Railways",
volume = "1115",
doi = "10.1007/978-3-030-37916-2_81"
}

Popović, Z., Mirković, N., Brajović, L., Rakić, D., Lazarević, L.,& Petričević, S.. (2020). Temperature Stresses in CWR – Experience of Serbian Railways. in Advances in Intelligent Systems and Computing
Springer, Cham., 1115.
https://doi.org/10.1007/978-3-030-37916-2_81

Popović Z, Mirković N, Brajović L, Rakić D, Lazarević L, Petričević S. Temperature Stresses in CWR – Experience of Serbian Railways. in Advances in Intelligent Systems and Computing. 2020;1115.
doi:10.1007/978-3-030-37916-2_81 .

Popović, Zdenka, Mirković, Nikola, Brajović, Ljiljana, Rakić, Dragan, Lazarević, Luka, Petričević, Slobodan, "Temperature Stresses in CWR – Experience of Serbian Railways" in Advances in Intelligent Systems and Computing, 1115 (2020),
https://doi.org/10.1007/978-3-030-37916-2_81 . .

TY  - GEN
AU  - Gospavić, Radovan
AU  - Todorović, Goran
AU  - Mirković-Marjanović, Milica
AU  - Brajović, Ljiljana
PY  - 2020
UR  - https://grafar.grf.bg.ac.rs/handle/123456789/3058
PB  - Univerzitet u Beogradu, Građevinski Fakultet
T1  - Софтверско-хардверско решење за  одређивање термалних одзивних фактора  за вишеслојни равански зид коришћењем Грин-ових (Green) функција
UR  - https://hdl.handle.net/21.15107/rcub_grafar_3058
ER  - 

@misc{
author = "Gospavić, Radovan and Todorović, Goran and Mirković-Marjanović, Milica and Brajović, Ljiljana",
year = "2020",
publisher = "Univerzitet u Beogradu, Građevinski Fakultet",
title = "Софтверско-хардверско решење за  одређивање термалних одзивних фактора  за вишеслојни равански зид коришћењем Грин-ових (Green) функција",
url = "https://hdl.handle.net/21.15107/rcub_grafar_3058"
}

Gospavić, R., Todorović, G., Mirković-Marjanović, M.,& Brajović, L.. (2020). Софтверско-хардверско решење за  одређивање термалних одзивних фактора  за вишеслојни равански зид коришћењем Грин-ових (Green) функција. 
Univerzitet u Beogradu, Građevinski Fakultet..
https://hdl.handle.net/21.15107/rcub_grafar_3058

Gospavić R, Todorović G, Mirković-Marjanović M, Brajović L. Софтверско-хардверско решење за  одређивање термалних одзивних фактора  за вишеслојни равански зид коришћењем Грин-ових (Green) функција. 2020;.
https://hdl.handle.net/21.15107/rcub_grafar_3058 .

Gospavić, Radovan, Todorović, Goran, Mirković-Marjanović, Milica, Brajović, Ljiljana, "Софтверско-хардверско решење за  одређивање термалних одзивних фактора  за вишеслојни равански зид коришћењем Грин-ових (Green) функција" (2020),
https://hdl.handle.net/21.15107/rcub_grafar_3058 .

TY  - CONF
AU  - Popović, Zdenka
AU  - Lazarević, Luka
AU  - Brajović, Ljiljana
AU  - Mićić, Milica
AU  - Mirković, Nikola
PY  - 2020
UR  - https://grafar.grf.bg.ac.rs/handle/123456789/2149
AB  - Based on the railway network performance, Infrastructure Manager is obligated to define the Maintenance plan for railway infrastructure, which contains corresponding values for intervention limits and alert limits. This paper considers vehicle response to track excitation due to the rail defect (code 2202 according to defect classification). It is indicated that theoretical models and acceleration measurements could be used to assess the quality of track geometry and ride comfort. The importance of early detection of irregularities of superstructure and substructure was emphasized. Moreover, the importance of inspection and preventive maintenance on the modern railway infrastructure was considered. According to the previous, the authors recommend nondestructive methods for inspection and early detection of irregularities of railway infrastructure.
PB  - EDP Sciences
T1  - Improvement recommendations for railway infrastructure maintenance
SP  - 01001
VL  - 157
DO  - 10.1051/e3sconf/202015701001
ER  - 

@conference{
author = "Popović, Zdenka and Lazarević, Luka and Brajović, Ljiljana and Mićić, Milica and Mirković, Nikola",
year = "2020",
abstract = "Based on the railway network performance, Infrastructure Manager is obligated to define the Maintenance plan for railway infrastructure, which contains corresponding values for intervention limits and alert limits. This paper considers vehicle response to track excitation due to the rail defect (code 2202 according to defect classification). It is indicated that theoretical models and acceleration measurements could be used to assess the quality of track geometry and ride comfort. The importance of early detection of irregularities of superstructure and substructure was emphasized. Moreover, the importance of inspection and preventive maintenance on the modern railway infrastructure was considered. According to the previous, the authors recommend nondestructive methods for inspection and early detection of irregularities of railway infrastructure.",
publisher = "EDP Sciences",
title = "Improvement recommendations for railway infrastructure maintenance",
pages = "01001",
volume = "157",
doi = "10.1051/e3sconf/202015701001"
}

Popović, Z., Lazarević, L., Brajović, L., Mićić, M.,& Mirković, N.. (2020). Improvement recommendations for railway infrastructure maintenance. 
EDP Sciences., 157, 01001.
https://doi.org/10.1051/e3sconf/202015701001

Popović Z, Lazarević L, Brajović L, Mićić M, Mirković N. Improvement recommendations for railway infrastructure maintenance. 2020;157:01001.
doi:10.1051/e3sconf/202015701001 .

Popović, Zdenka, Lazarević, Luka, Brajović, Ljiljana, Mićić, Milica, Mirković, Nikola, "Improvement recommendations for railway infrastructure maintenance", 157 (2020):01001,
https://doi.org/10.1051/e3sconf/202015701001 . .

TY  - JOUR
AU  - Stojanovic, Dusica
AU  - Brajović, Ljiljana
AU  - Obradovic, Vera
AU  - Mijailovic, Daniel
AU  - Dramlic, Dragan
AU  - Kojovic, Aleksandar
AU  - Uskokovic, Petar
PY  - 2020
UR  - https://grafar.grf.bg.ac.rs/handle/123456789/1946
AB  - The composite nanofibers were used as reinforcement in acrylic polymer for the overall enhancement of thermomechanical
properties, adhesion between fibers and matrix, and fracture toughness of the final nanocomposite
since acrylic materials lack of this feature. So, a good balance between hardness/toughness and transparency is
obtained with the addition of poly (vinyl butyral) (PVB) and titania (TiO2) nanofibers simultaneously and
controlling their contents. Specifically, when compared to that of pure acrylic polymer, the fracture toughness of
the PMMA nanocomposite apparently increased 55 % with the addition of 3 wt.% titania nanoparticles, while
the produced nanocomposite maintained high transmittance above 75–80% in the visible domain. The transmission
spectrum modelling of the reinforced fiber materials and hybrid acrylic composites using Mie scattering
theory for different particle sizes and particle content is presented. The calculated transmission coefficients
versus wavelength are compared with the experimental ones.
PB  - Elsevier
T2  - Progress in Organic Coatings
T1  - Hybrid acrylic nanocomposites with excellent transparency and hardness/toughness balance
SP  - 105437
VL  - 139
VL  - 139
DO  - 10.1016/j.porgcoat.2019.105437
ER  - 

@article{
author = "Stojanovic, Dusica and Brajović, Ljiljana and Obradovic, Vera and Mijailovic, Daniel and Dramlic, Dragan and Kojovic, Aleksandar and Uskokovic, Petar",
year = "2020",
abstract = "The composite nanofibers were used as reinforcement in acrylic polymer for the overall enhancement of thermomechanical
properties, adhesion between fibers and matrix, and fracture toughness of the final nanocomposite
since acrylic materials lack of this feature. So, a good balance between hardness/toughness and transparency is
obtained with the addition of poly (vinyl butyral) (PVB) and titania (TiO2) nanofibers simultaneously and
controlling their contents. Specifically, when compared to that of pure acrylic polymer, the fracture toughness of
the PMMA nanocomposite apparently increased 55 % with the addition of 3 wt.% titania nanoparticles, while
the produced nanocomposite maintained high transmittance above 75–80% in the visible domain. The transmission
spectrum modelling of the reinforced fiber materials and hybrid acrylic composites using Mie scattering
theory for different particle sizes and particle content is presented. The calculated transmission coefficients
versus wavelength are compared with the experimental ones.",
publisher = "Elsevier",
journal = "Progress in Organic Coatings",
title = "Hybrid acrylic nanocomposites with excellent transparency and hardness/toughness balance",
pages = "105437",
volume = "139, 139",
doi = "10.1016/j.porgcoat.2019.105437"
}

Stojanovic, D., Brajović, L., Obradovic, V., Mijailovic, D., Dramlic, D., Kojovic, A.,& Uskokovic, P.. (2020). Hybrid acrylic nanocomposites with excellent transparency and hardness/toughness balance. in Progress in Organic Coatings
Elsevier., 139, 105437.
https://doi.org/10.1016/j.porgcoat.2019.105437

Stojanovic D, Brajović L, Obradovic V, Mijailovic D, Dramlic D, Kojovic A, Uskokovic P. Hybrid acrylic nanocomposites with excellent transparency and hardness/toughness balance. in Progress in Organic Coatings. 2020;139:105437.
doi:10.1016/j.porgcoat.2019.105437 .

Stojanovic, Dusica, Brajović, Ljiljana, Obradovic, Vera, Mijailovic, Daniel, Dramlic, Dragan, Kojovic, Aleksandar, Uskokovic, Petar, "Hybrid acrylic nanocomposites with excellent transparency and hardness/toughness balance" in Progress in Organic Coatings, 139 (2020):105437,
https://doi.org/10.1016/j.porgcoat.2019.105437 . .

TY  - JOUR
AU  - Mirković, Nikola
AU  - Brajović, Ljiljana
AU  - Malović, Miodrag
AU  - Vnenk, Petr
PY  - 2019
UR  - https://grafar.grf.bg.ac.rs/handle/123456789/2794
AB  - Continuously welded rails are a part of the track structure since the
1950s. Total stresses in continuously welded rails include residual stresses gen-
erated during the manufacturing process as well as the service life of rails. The
control of rail stresses is very important for traffic safety. Measurement meth-
ods for residual stress in rails are presented in this paper. Since destructive
measurement methods are unsuitable for use in the railway track, the modern
non-destructive methods were particularly presented and discussed. The ad-
vantages and disadvantages of X-ray diffraction, ultrasonic, magnetic and elec-
tromagnetic methods are particularly explained and considered.
T2  - Advances in Intelligent Systems and Computing
T1  - Measurement Methods for Residual Stresses in CWR
VL  - 982
DO  - 10.1007/978-3-030-19756-8_32
ER  - 

@article{
author = "Mirković, Nikola and Brajović, Ljiljana and Malović, Miodrag and Vnenk, Petr",
year = "2019",
abstract = "Continuously welded rails are a part of the track structure since the
1950s. Total stresses in continuously welded rails include residual stresses gen-
erated during the manufacturing process as well as the service life of rails. The
control of rail stresses is very important for traffic safety. Measurement meth-
ods for residual stress in rails are presented in this paper. Since destructive
measurement methods are unsuitable for use in the railway track, the modern
non-destructive methods were particularly presented and discussed. The ad-
vantages and disadvantages of X-ray diffraction, ultrasonic, magnetic and elec-
tromagnetic methods are particularly explained and considered.",
journal = "Advances in Intelligent Systems and Computing",
title = "Measurement Methods for Residual Stresses in CWR",
volume = "982",
doi = "10.1007/978-3-030-19756-8_32"
}

Mirković, N., Brajović, L., Malović, M.,& Vnenk, P.. (2019). Measurement Methods for Residual Stresses in CWR. in Advances in Intelligent Systems and Computing, 982.
https://doi.org/10.1007/978-3-030-19756-8_32

Mirković N, Brajović L, Malović M, Vnenk P. Measurement Methods for Residual Stresses in CWR. in Advances in Intelligent Systems and Computing. 2019;982.
doi:10.1007/978-3-030-19756-8_32 .

Mirković, Nikola, Brajović, Ljiljana, Malović, Miodrag, Vnenk, Petr, "Measurement Methods for Residual Stresses in CWR" in Advances in Intelligent Systems and Computing, 982 (2019),
https://doi.org/10.1007/978-3-030-19756-8_32 . .

TY  - CONF
AU  - Mićić, Milica
AU  - Brajović, Ljiljana
AU  - Pustovgar, Andrey
PY  - 2018
UR  - https://grafar.grf.bg.ac.rs/handle/123456789/1610
AB  - This paper proposes a methodology for statistical analysis of data obtained by visual inspection of squat defects on the rail head. Rail inspection by visual observation, including measurement of the squat defect position and depth was performed in Pančevo Varoš railway station in 2017. The obtained data about the squat rail defect (defect type 227 according to the UIC 712) on the main tracks was analysed in this paper. The rail defect position was determined regarding the position of the nearest sleeper in the track. Statistical analysis of the occurrence of squat rail defect was conducted according to the performed visual inspection in the field. Statistical data processing was performed for tracks zones according to the vertical stiffness of rail support. Furthermore, the impact of traffic load, the type and the arrangement of sleepers on the appearance of the squat rail defect was considered.
PB  - Faculty of Mechanical Engineering, Niš
C3  - Proceedings / XVIII Scientific-expert conference on railways - RAILCON 18, october 11-12, 2018, Niš
T1  - Methodology for statistical analysis of squat rail defects
EP  - 160
SP  - 157
UR  - https://hdl.handle.net/21.15107/rcub_grafar_1610
ER  - 

@conference{
author = "Mićić, Milica and Brajović, Ljiljana and Pustovgar, Andrey",
year = "2018",
abstract = "This paper proposes a methodology for statistical analysis of data obtained by visual inspection of squat defects on the rail head. Rail inspection by visual observation, including measurement of the squat defect position and depth was performed in Pančevo Varoš railway station in 2017. The obtained data about the squat rail defect (defect type 227 according to the UIC 712) on the main tracks was analysed in this paper. The rail defect position was determined regarding the position of the nearest sleeper in the track. Statistical analysis of the occurrence of squat rail defect was conducted according to the performed visual inspection in the field. Statistical data processing was performed for tracks zones according to the vertical stiffness of rail support. Furthermore, the impact of traffic load, the type and the arrangement of sleepers on the appearance of the squat rail defect was considered.",
publisher = "Faculty of Mechanical Engineering, Niš",
journal = "Proceedings / XVIII Scientific-expert conference on railways - RAILCON 18, october 11-12, 2018, Niš",
title = "Methodology for statistical analysis of squat rail defects",
pages = "160-157",
url = "https://hdl.handle.net/21.15107/rcub_grafar_1610"
}

Mićić, M., Brajović, L.,& Pustovgar, A.. (2018). Methodology for statistical analysis of squat rail defects. in Proceedings / XVIII Scientific-expert conference on railways - RAILCON 18, october 11-12, 2018, Niš
Faculty of Mechanical Engineering, Niš., 157-160.
https://hdl.handle.net/21.15107/rcub_grafar_1610

Mićić M, Brajović L, Pustovgar A. Methodology for statistical analysis of squat rail defects. in Proceedings / XVIII Scientific-expert conference on railways - RAILCON 18, october 11-12, 2018, Niš. 2018;:157-160.
https://hdl.handle.net/21.15107/rcub_grafar_1610 .

Mićić, Milica, Brajović, Ljiljana, Pustovgar, Andrey, "Methodology for statistical analysis of squat rail defects" in Proceedings / XVIII Scientific-expert conference on railways - RAILCON 18, october 11-12, 2018, Niš (2018):157-160,
https://hdl.handle.net/21.15107/rcub_grafar_1610 .

TY  - CONF
AU  - Mirković, Nikola
AU  - Brajović, Ljiljana
AU  - Malović, Miodrag
PY  - 2018
UR  - https://grafar.grf.bg.ac.rs/handle/123456789/1600
AB  - The residual stresses in rails are generated during the manufacturing process and have uneven distribution in rail cross section. The residual stress is a part of basic tensile stress in rail foot. For used rail, the residual stress value of 80 MPa is commonly used in the engineering calculations. On the other hand, the standard EN 13674 prescribes residual stress values up to 250 MPa and destructive method using electrical strain gauge for measurement of rail residual stress. Since destructive measurement methods are unsuitable for use in the track, the possible non-destructive in situ methods for measuring of residual stresses in the rails are discussed in this paper. The fundamentals of X-ray diffraction, ultrasonic, magnetic and electromagnetic methods are explained, as well as, their advantages and disadvantages.
PB  - Faculty of Mechanical Engineering, Niš
C3  - Proceedings / XVIII Scientific-expert conference on railways - RAILCON 18, october 11-12, 2018, Niš
T1  - Methods for determination of residual stress in rail
EP  - 116
SP  - 113
UR  - https://hdl.handle.net/21.15107/rcub_grafar_1600
ER  - 

@conference{
author = "Mirković, Nikola and Brajović, Ljiljana and Malović, Miodrag",
year = "2018",
abstract = "The residual stresses in rails are generated during the manufacturing process and have uneven distribution in rail cross section. The residual stress is a part of basic tensile stress in rail foot. For used rail, the residual stress value of 80 MPa is commonly used in the engineering calculations. On the other hand, the standard EN 13674 prescribes residual stress values up to 250 MPa and destructive method using electrical strain gauge for measurement of rail residual stress. Since destructive measurement methods are unsuitable for use in the track, the possible non-destructive in situ methods for measuring of residual stresses in the rails are discussed in this paper. The fundamentals of X-ray diffraction, ultrasonic, magnetic and electromagnetic methods are explained, as well as, their advantages and disadvantages.",
publisher = "Faculty of Mechanical Engineering, Niš",
journal = "Proceedings / XVIII Scientific-expert conference on railways - RAILCON 18, october 11-12, 2018, Niš",
title = "Methods for determination of residual stress in rail",
pages = "116-113",
url = "https://hdl.handle.net/21.15107/rcub_grafar_1600"
}

Mirković, N., Brajović, L.,& Malović, M.. (2018). Methods for determination of residual stress in rail. in Proceedings / XVIII Scientific-expert conference on railways - RAILCON 18, october 11-12, 2018, Niš
Faculty of Mechanical Engineering, Niš., 113-116.
https://hdl.handle.net/21.15107/rcub_grafar_1600

Mirković N, Brajović L, Malović M. Methods for determination of residual stress in rail. in Proceedings / XVIII Scientific-expert conference on railways - RAILCON 18, october 11-12, 2018, Niš. 2018;:113-116.
https://hdl.handle.net/21.15107/rcub_grafar_1600 .

Mirković, Nikola, Brajović, Ljiljana, Malović, Miodrag, "Methods for determination of residual stress in rail" in Proceedings / XVIII Scientific-expert conference on railways - RAILCON 18, october 11-12, 2018, Niš (2018):113-116,
https://hdl.handle.net/21.15107/rcub_grafar_1600 .

TY  - CONF
AU  - Mićić, Milica
AU  - Brajović, Ljiljana
AU  - Lazarević, Luka
AU  - Mirković, Nikola
PY  - 2017
UR  - https://grafar.grf.bg.ac.rs/handle/123456789/2792
AB  - Track stiffness is a parameter which significantly influences to the track geometry 
deterioration, rail fatigue and deterioration of other superstructure and substructure components 
during the track service life. Track stiffness measurement has great theoretical and practical 
importance for the design of new railway lines, as well as for upgrade and maintenance of existing 
railway lines. This paper analyses standstill and continuous measurement methods for static and 
dynamic track stiffness, which are used worldwide. In addition, it presents measurement 
principles and performances used for inspection vehicles and devices, and guidelines for selection 
of the optimal method for stiffness measurement depending on the user requirements.
PB  - University of East Sarajevo,  Faculty of Transport and Traffic  Engineering Doboj
C3  - VI International Symposium New Horizons of Transport and Communications
T1  - Methods for track stiffness measurement - State of the art
EP  - 387
SP  - 378
UR  - https://hdl.handle.net/21.15107/rcub_grafar_2792
ER  - 

@conference{
author = "Mićić, Milica and Brajović, Ljiljana and Lazarević, Luka and Mirković, Nikola",
year = "2017",
abstract = "Track stiffness is a parameter which significantly influences to the track geometry 
deterioration, rail fatigue and deterioration of other superstructure and substructure components 
during the track service life. Track stiffness measurement has great theoretical and practical 
importance for the design of new railway lines, as well as for upgrade and maintenance of existing 
railway lines. This paper analyses standstill and continuous measurement methods for static and 
dynamic track stiffness, which are used worldwide. In addition, it presents measurement 
principles and performances used for inspection vehicles and devices, and guidelines for selection 
of the optimal method for stiffness measurement depending on the user requirements.",
publisher = "University of East Sarajevo,  Faculty of Transport and Traffic  Engineering Doboj",
journal = "VI International Symposium New Horizons of Transport and Communications",
title = "Methods for track stiffness measurement - State of the art",
pages = "387-378",
url = "https://hdl.handle.net/21.15107/rcub_grafar_2792"
}

Mićić, M., Brajović, L., Lazarević, L.,& Mirković, N.. (2017). Methods for track stiffness measurement - State of the art. in VI International Symposium New Horizons of Transport and Communications
University of East Sarajevo,  Faculty of Transport and Traffic  Engineering Doboj., 378-387.
https://hdl.handle.net/21.15107/rcub_grafar_2792

Mićić M, Brajović L, Lazarević L, Mirković N. Methods for track stiffness measurement - State of the art. in VI International Symposium New Horizons of Transport and Communications. 2017;:378-387.
https://hdl.handle.net/21.15107/rcub_grafar_2792 .

Mićić, Milica, Brajović, Ljiljana, Lazarević, Luka, Mirković, Nikola, "Methods for track stiffness measurement - State of the art" in VI International Symposium New Horizons of Transport and Communications (2017):378-387,
https://hdl.handle.net/21.15107/rcub_grafar_2792 .