TY  - JOUR
AU  - Nina, Aleksandra
AU  - Nico, Giovanni
AU  - Odalović, Oleg
AU  - Čadež, Vladimir M.
AU  - Todorović-Drakul, Miljana
AU  - Radovanović, Milan
AU  - Popović, Luka Č.
PY  - 2019
UR  - https://grafar.grf.bg.ac.rs/handle/123456789/1760
AB  - We investigate the influence of the perturbed (by a solar X-ray flare) ionospheric D-region on the GNSS and SAR signals. We calculate a signal delay in the D-region based on the low ionospheric monitoring by very low frequency (VLF) radio waves. Results show that the ionospheric delay in the perturbed D-region can be important and, therefore, should be taken into account in modeling the ionospheric influence on the GNSS and SAR signal propagation and in calculations relevant for space geodesy. This conclusion is significant because numerous existing models ignore the
impact of this ionospheric part on the GNSS and SAR signals due to its small electron density which is true only in quiet conditions and can result in significant errors in space geodesy during intensive ionospheric disturbances.
PB  - IEEE (Institute of Electrical and Electronics Engineers)
T2  - IEEE Geoscience and Remote Sensing Letters
T1  - GNSS and SAR Signal Delay in Perturbed Ionospheric D-Region During Solar X-Ray Flares
DO  - 10.1109/LGRS.2019.2941643
ER  - 

@article{
author = "Nina, Aleksandra and Nico, Giovanni and Odalović, Oleg and Čadež, Vladimir M. and Todorović-Drakul, Miljana and Radovanović, Milan and Popović, Luka Č.",
year = "2019",
abstract = "We investigate the influence of the perturbed (by a solar X-ray flare) ionospheric D-region on the GNSS and SAR signals. We calculate a signal delay in the D-region based on the low ionospheric monitoring by very low frequency (VLF) radio waves. Results show that the ionospheric delay in the perturbed D-region can be important and, therefore, should be taken into account in modeling the ionospheric influence on the GNSS and SAR signal propagation and in calculations relevant for space geodesy. This conclusion is significant because numerous existing models ignore the
impact of this ionospheric part on the GNSS and SAR signals due to its small electron density which is true only in quiet conditions and can result in significant errors in space geodesy during intensive ionospheric disturbances.",
publisher = "IEEE (Institute of Electrical and Electronics Engineers)",
journal = "IEEE Geoscience and Remote Sensing Letters",
title = "GNSS and SAR Signal Delay in Perturbed Ionospheric D-Region During Solar X-Ray Flares",
doi = "10.1109/LGRS.2019.2941643"
}

Nina, A., Nico, G., Odalović, O., Čadež, V. M., Todorović-Drakul, M., Radovanović, M.,& Popović, L. Č.. (2019). GNSS and SAR Signal Delay in Perturbed Ionospheric D-Region During Solar X-Ray Flares. in IEEE Geoscience and Remote Sensing Letters
IEEE (Institute of Electrical and Electronics Engineers)..
https://doi.org/10.1109/LGRS.2019.2941643

Nina A, Nico G, Odalović O, Čadež VM, Todorović-Drakul M, Radovanović M, Popović LČ. GNSS and SAR Signal Delay in Perturbed Ionospheric D-Region During Solar X-Ray Flares. in IEEE Geoscience and Remote Sensing Letters. 2019;.
doi:10.1109/LGRS.2019.2941643 .

Nina, Aleksandra, Nico, Giovanni, Odalović, Oleg, Čadež, Vladimir M., Todorović-Drakul, Miljana, Radovanović, Milan, Popović, Luka Č., "GNSS and SAR Signal Delay in Perturbed Ionospheric D-Region During Solar X-Ray Flares" in IEEE Geoscience and Remote Sensing Letters (2019),
https://doi.org/10.1109/LGRS.2019.2941643 . .

TY  - JOUR
AU  - Stojanović, Goran
AU  - Radovanović, Milan
AU  - Krstić, Dejan
AU  - Ignjatović, Ivan
AU  - Dragaš, Jelena
AU  - Carević, Vedran
PY  - 2019
UR  - https://grafar.grf.bg.ac.rs/handle/123456789/1725
AB  - Concrete is a material that is widely used by mankind. Although different deterioration mechanisms can lead to degradation of the concrete itself, reinforcement corrosion is the biggest durability issue for reinforced concrete structures. One of the key parameters influencing the corrosion rate is pH value. Accordingly, this work presents two capacitive sensor platforms—one based on parallel plate electrodes and the other based on a planar interdigitated electrode structure. The first platform is used to determine whether the pH value is lower or higher than a predetermined limit (around 11) and this device was successfully tested using concrete suspensions. The second platform can determine the pH value by establishing a relationship between pH and measured capacitance from a powdered concrete specimen. Both multi-layered platforms were manufactured by means of a cost-effective xurography technique, which provides technically and mechanically robust structures very quickly.
PB  - Basel : MDPI
T2  - Applied Sciences
T1  - Determination of pH in Powdered Concrete Samples or in Suspension
IS  - 16
SP  - 3257
VL  - 9
DO  - 10.3390/app9163257
ER  - 

@article{
author = "Stojanović, Goran and Radovanović, Milan and Krstić, Dejan and Ignjatović, Ivan and Dragaš, Jelena and Carević, Vedran",
year = "2019",
abstract = "Concrete is a material that is widely used by mankind. Although different deterioration mechanisms can lead to degradation of the concrete itself, reinforcement corrosion is the biggest durability issue for reinforced concrete structures. One of the key parameters influencing the corrosion rate is pH value. Accordingly, this work presents two capacitive sensor platforms—one based on parallel plate electrodes and the other based on a planar interdigitated electrode structure. The first platform is used to determine whether the pH value is lower or higher than a predetermined limit (around 11) and this device was successfully tested using concrete suspensions. The second platform can determine the pH value by establishing a relationship between pH and measured capacitance from a powdered concrete specimen. Both multi-layered platforms were manufactured by means of a cost-effective xurography technique, which provides technically and mechanically robust structures very quickly.",
publisher = "Basel : MDPI",
journal = "Applied Sciences",
title = "Determination of pH in Powdered Concrete Samples or in Suspension",
number = "16",
pages = "3257",
volume = "9",
doi = "10.3390/app9163257"
}

Stojanović, G., Radovanović, M., Krstić, D., Ignjatović, I., Dragaš, J.,& Carević, V.. (2019). Determination of pH in Powdered Concrete Samples or in Suspension. in Applied Sciences
Basel : MDPI., 9(16), 3257.
https://doi.org/10.3390/app9163257

Stojanović G, Radovanović M, Krstić D, Ignjatović I, Dragaš J, Carević V. Determination of pH in Powdered Concrete Samples or in Suspension. in Applied Sciences. 2019;9(16):3257.
doi:10.3390/app9163257 .

Stojanović, Goran, Radovanović, Milan, Krstić, Dejan, Ignjatović, Ivan, Dragaš, Jelena, Carević, Vedran, "Determination of pH in Powdered Concrete Samples or in Suspension" in Applied Sciences, 9, no. 16 (2019):3257,
https://doi.org/10.3390/app9163257 . .