A. Vidmar - Academia.edu (original) (raw)
Papers by A. Vidmar
Sensors
Temperature measurements are widely used in structural health monitoring. Optical fiber distribut... more Temperature measurements are widely used in structural health monitoring. Optical fiber distributed temperature sensors (DTS) are developed, based on Raman spectroscopy, to measure temperature with relatively high accuracy and short temporal and spatial resolutions. DTS systems provide an extensive number of temperature measurements along the entire length of an optical fiber that can be extended to tens of kilometers. The efficiency of the temperature measurement strongly depends on the calibration of the DTS data. Although DTS systems internally calibrate the data, manual calibration techniques were developed to achieve more accurate results. Manual calibration employs reference sections or points with known temperatures and the DTS scattering data to estimate the calibration parameters and calculate temperature along the optical fiber. In some applications, manual calibration is subjected to some shortages, based on the proposed fiber installation configuration and continuity of ...
Hydrological Processes of the Danube River Basin, 2010
Doktorska disertacija obravnava področje hidrologije in hidroloških modelov. Hidrološki pojavi se... more Doktorska disertacija obravnava področje hidrologije in hidroloških modelov. Hidrološki pojavi se oblikujejo v hidrološkem sistemu, ki ga določa narava in so v osnovi stohastični. Pojavi so enkratni, neponovljivi in spreminjajoči se v prostoru in času. Simuliramo jih s pomočjo različnih hidroloških modelov, s katerimi poskušamo integrirati kompleksne procese, ki jih ponazarjajo zvezne funkcije. V preteklosti so bili razviti različni modeli, ki simulirajo različne hidrološke procese. Vendar so neskladja med simuliranimi in merjenimi vrednostmi še vedno velika in predstavljajo izziv mnogim raziskovalcem. Modeli vsebujejo veliko parametrov, ki jih je nemogoče neposredno izmeriti. Vrednosti večine teh parametrov so določene v postopku umerjanja, ki pogojuje učinkovitost takšnih modelov. Postopek umerjanja modela je obremenjen s pomanjkanjem podatkov in poenostavitvami, s katerimi rešujemo matematični model. Omenjene obremenitve povzročajo šume oziroma odstopanja med rezultati izračuna, ...
Kamniska Bistrica is torrent river that drainage water from alpine mountains and flow through all... more Kamniska Bistrica is torrent river that drainage water from alpine mountains and flow through alluvial plain. On the plain area water from river derivates in 11 millstream and recharge groundwater also. During low flows parts of the stream suffer without water. Network of water station was developed and discharge measurement derived by Doppler velocity meter. Recharge of groundwater was calculated
Cooling water for the Nuclear Power Plant Kr ko (NPPK) is provided from the Sava River. In the ne... more Cooling water for the Nuclear Power Plant Kr ko (NPPK) is provided from the Sava River. In the next years, a dam with a HEPP will be constructed 7 km downstream and the water level will be raised for 3 m. Numerical simulations of the flow, sedimentation and thermal pollution had to be made for the future conditions. Detailed 3D measurements of the flow in the present situation were made by a floating ADCP instrument and compared with the results of some versions of the 3D model. In greatest part of the river section a good agreement is obtained. However, near the intake to the inflow channel an underwater wall is directing the flow which is complex, the vertical velocity components locally attaining over 20 % of the horizontal components. Here the difference between the simulated and measured velocity vectors is hardly acceptable. The same model has also been supplemented for the simulation of thermal pollution, where agreement with the measurements is very good. Some cases of simul...
Natural Hazards and Earth System Sciences Discussions, 2015
In May 2014, extreme floods occurred in the lower Sava River basin, causing major damage, with ca... more In May 2014, extreme floods occurred in the lower Sava River basin, causing major damage, with catastrophic consequences. Based on the data gathered, the weather situation in Bosnia and Herzegovina's (BiH) Bosna River basin was analysed and the hydrological conditions were provided, including the results of the probability analysis of the size of the recorded precipitation and flow rates. A hydrological model of the Bosna River basin was developed using HBV-light for the purposes of reconstructing and forecasting such events more effectively. All analyses confirmed that the May 2014 event was an extreme event whose returning period greatly exceeds 100 years.
Accurate discharge estimation is important for an efficient river basin management and especially... more Accurate discharge estimation is important for an efficient river basin management and especially for flood forecasting. The traditional way of estimating the discharge in hydrological practice is to measure the water stage and to convert the recorded water stage values into discharge by using the single-valued rating curve .Relationship between the stage and discharge values of the rating curve for
Snow is a type of precipitation in the form of crystalline water ice, consisting of a multitude o... more Snow is a type of precipitation in the form of crystalline water ice, consisting of a multitude of snowflakes that fall from clouds. Snow remains on the ground until it melts or sublimates. Spring snow melt is a major source of water supply to areas in temperate zones near mountains that catch and hold winter snow, especially those with a
The Dragonja experimental river basin was established in late 1999. The area belongs to the sub- ... more The Dragonja experimental river basin was established in late 1999. The area belongs to the sub- Mediterranean climate region and it is geologically composed on Eocene flysch. The region is interesting because in the last few decades it has been subjected to intensive natural reforestation as a consequence of discontinued agricultural land use. This has caused a decrease in minimal
Understanding of interactions between hydrological and biogeochemical responses of catchments on ... more Understanding of interactions between hydrological and biogeochemical responses of catchments on rainfall events which is usually unclear from periodic measurements and requires tracing of the temporal dynamics of the processes. Smaller streams reflect strong connections between hydrological processes of the rainfall runoff formation and biogeochemical processes in the watershed, consequently, the responsiveness of the streamwater chemistry to changed hydrological states is very high. The study was carried out in 2006, within the 42 km 2 forested Padež watershed in the southwestern part of Slovenia, which is characterized by distinctive flushing, an almost torrential hydrological regime influenced by impermeable flysch geological settings. More than 15 recorded hydrographs which, in the hydrological and biogeochemical sense, differed substantially, disclosed a highly variable but at the same time a strong linkage between hydrological and biogeochemical controls of nitrate exports from the spatial perspective of a watershed.
The Reka river is the widest known sinking stream of the Classical Karst area in Slovenia, and it... more The Reka river is the widest known sinking stream of the Classical Karst area in Slovenia, and it has been studied since the Antiquity. The river sinks into the Škocjan Cave system, which was proclaimed by UNESCO as a World Heritage Site in 1986. The Reka river basin is situated in the southern part of Slovenia and has an area of 442 km2 and a mean discharge of 8.2 m3/s. The basin has a unique geological structure; it is situated on the Brkini syncline Eocene flysch rocks surrounded by a large karstic region. The stream network density is about 1.696 km/km2. The water from the northern karstic formation belongs to the Danube River Basin, while the water from the southern part drains into the Adriatic Sea. There is an underground bifurcation from which the surface water flows to the Danube River and the underground water drains in the Bistrica Spring, a tributary of the Reka River.
Proceedings of the International Association of Hydrological Sciences, 2014
IOP Conference Series: Earth and Environmental Science, 2008
Experimental watersheds are critical to the advancement of hydrological science. By setting up th... more Experimental watersheds are critical to the advancement of hydrological science. By setting up three experimental watersheds, Slovenia also obtained its grounds for further development of the science and discipline. In the Dragonja experimental watershed the studies are focused on the afforestation of the watershed in a mediterranean climate, on the Reka river the water balance in a partly karstic area is examined, and on the case of the Glinščica stream the implications of the urban environment are studied. We have obtained valuable experience and tested new measuring equipment in all three experimental watersheds.
Natural Hazards and Earth System Sciences, 2005
A medium-ranged high performance handheld reflectorless laser measurement system, was used for a ... more A medium-ranged high performance handheld reflectorless laser measurement system, was used for a morphological survey on the Strug rock fall in W Slovenia in the period from August 2003 to August 2004. The purpose was to evaluate its potential for monitoring ground surface changes in rock fall source areas and to help evaluating morphological changes by measuring distance from fixed points. In the area, 21 fixed geodetic points have been established. Altogether, seven measurement sets with more than 5500 points have been gathered in the rock fall area. Choosing a point cloud with a density of less than 1 point per 10 m 2 on a very rough rock fall surface failed to be a good solution. The changes on larger areas were shown by displacements of selected significantly large-sized rock blocks with a volume of several m 3. Because only smaller changes were observed between the single field series, the rock fall surface generally remained unchanged. Local surface changes of the order of 1 m or more, were clearly shown by measurements in the selected referenced cross sections. The usage of these cross sections gave a possibility to evaluate volumetric changes on the surface. The laser measurement system provided a good replacement for the classical terrestrial geodetic survey equipment, especially when performing remote monitoring of morphological changes in rock fall hazard zones, however, the case is different when fixed points are to be measured precisely.
The integral digital information on the waters of Slovenia is developed. This is a system of aggr... more The integral digital information on the waters of Slovenia is developed. This is a system of aggregated, verified and logically integrated information on the state of waters in Slovenia, the pressures on the water environments and its protection. Data sources are national information evidence and monitoring systems managed by public service organisations and other expert institutions. The information system is a source for planning in water management, environmental state reporting, and performance indicators evaluation. It is based on country based catchment register. The system incorporates 31 information thematic layers that are organised in the DPSIR (driving forces, pressure, state, impact, and response) system. Data for the information themes are organised with the AutoCad MAP 4.5 GIS tool and prepared for browsing with Internet.
IOP Conference Series: Earth and Environmental Science, 2008
Nowadays remote sensing data are great value for many ways of use as for snow hydrology. Snow cov... more Nowadays remote sensing data are great value for many ways of use as for snow hydrology. Snow cover mapping on basis of satellite images is widely spread because it is easier than in-situ measuring and interpolating. To verify the use of satellite imagery (MODIS product) we used all available data of snow cover and satellite images and compared detected snow
Sensors
Temperature measurements are widely used in structural health monitoring. Optical fiber distribut... more Temperature measurements are widely used in structural health monitoring. Optical fiber distributed temperature sensors (DTS) are developed, based on Raman spectroscopy, to measure temperature with relatively high accuracy and short temporal and spatial resolutions. DTS systems provide an extensive number of temperature measurements along the entire length of an optical fiber that can be extended to tens of kilometers. The efficiency of the temperature measurement strongly depends on the calibration of the DTS data. Although DTS systems internally calibrate the data, manual calibration techniques were developed to achieve more accurate results. Manual calibration employs reference sections or points with known temperatures and the DTS scattering data to estimate the calibration parameters and calculate temperature along the optical fiber. In some applications, manual calibration is subjected to some shortages, based on the proposed fiber installation configuration and continuity of ...
Hydrological Processes of the Danube River Basin, 2010
Doktorska disertacija obravnava področje hidrologije in hidroloških modelov. Hidrološki pojavi se... more Doktorska disertacija obravnava področje hidrologije in hidroloških modelov. Hidrološki pojavi se oblikujejo v hidrološkem sistemu, ki ga določa narava in so v osnovi stohastični. Pojavi so enkratni, neponovljivi in spreminjajoči se v prostoru in času. Simuliramo jih s pomočjo različnih hidroloških modelov, s katerimi poskušamo integrirati kompleksne procese, ki jih ponazarjajo zvezne funkcije. V preteklosti so bili razviti različni modeli, ki simulirajo različne hidrološke procese. Vendar so neskladja med simuliranimi in merjenimi vrednostmi še vedno velika in predstavljajo izziv mnogim raziskovalcem. Modeli vsebujejo veliko parametrov, ki jih je nemogoče neposredno izmeriti. Vrednosti večine teh parametrov so določene v postopku umerjanja, ki pogojuje učinkovitost takšnih modelov. Postopek umerjanja modela je obremenjen s pomanjkanjem podatkov in poenostavitvami, s katerimi rešujemo matematični model. Omenjene obremenitve povzročajo šume oziroma odstopanja med rezultati izračuna, ...
Kamniska Bistrica is torrent river that drainage water from alpine mountains and flow through all... more Kamniska Bistrica is torrent river that drainage water from alpine mountains and flow through alluvial plain. On the plain area water from river derivates in 11 millstream and recharge groundwater also. During low flows parts of the stream suffer without water. Network of water station was developed and discharge measurement derived by Doppler velocity meter. Recharge of groundwater was calculated
Cooling water for the Nuclear Power Plant Kr ko (NPPK) is provided from the Sava River. In the ne... more Cooling water for the Nuclear Power Plant Kr ko (NPPK) is provided from the Sava River. In the next years, a dam with a HEPP will be constructed 7 km downstream and the water level will be raised for 3 m. Numerical simulations of the flow, sedimentation and thermal pollution had to be made for the future conditions. Detailed 3D measurements of the flow in the present situation were made by a floating ADCP instrument and compared with the results of some versions of the 3D model. In greatest part of the river section a good agreement is obtained. However, near the intake to the inflow channel an underwater wall is directing the flow which is complex, the vertical velocity components locally attaining over 20 % of the horizontal components. Here the difference between the simulated and measured velocity vectors is hardly acceptable. The same model has also been supplemented for the simulation of thermal pollution, where agreement with the measurements is very good. Some cases of simul...
Natural Hazards and Earth System Sciences Discussions, 2015
In May 2014, extreme floods occurred in the lower Sava River basin, causing major damage, with ca... more In May 2014, extreme floods occurred in the lower Sava River basin, causing major damage, with catastrophic consequences. Based on the data gathered, the weather situation in Bosnia and Herzegovina's (BiH) Bosna River basin was analysed and the hydrological conditions were provided, including the results of the probability analysis of the size of the recorded precipitation and flow rates. A hydrological model of the Bosna River basin was developed using HBV-light for the purposes of reconstructing and forecasting such events more effectively. All analyses confirmed that the May 2014 event was an extreme event whose returning period greatly exceeds 100 years.
Accurate discharge estimation is important for an efficient river basin management and especially... more Accurate discharge estimation is important for an efficient river basin management and especially for flood forecasting. The traditional way of estimating the discharge in hydrological practice is to measure the water stage and to convert the recorded water stage values into discharge by using the single-valued rating curve .Relationship between the stage and discharge values of the rating curve for
Snow is a type of precipitation in the form of crystalline water ice, consisting of a multitude o... more Snow is a type of precipitation in the form of crystalline water ice, consisting of a multitude of snowflakes that fall from clouds. Snow remains on the ground until it melts or sublimates. Spring snow melt is a major source of water supply to areas in temperate zones near mountains that catch and hold winter snow, especially those with a
The Dragonja experimental river basin was established in late 1999. The area belongs to the sub- ... more The Dragonja experimental river basin was established in late 1999. The area belongs to the sub- Mediterranean climate region and it is geologically composed on Eocene flysch. The region is interesting because in the last few decades it has been subjected to intensive natural reforestation as a consequence of discontinued agricultural land use. This has caused a decrease in minimal
Understanding of interactions between hydrological and biogeochemical responses of catchments on ... more Understanding of interactions between hydrological and biogeochemical responses of catchments on rainfall events which is usually unclear from periodic measurements and requires tracing of the temporal dynamics of the processes. Smaller streams reflect strong connections between hydrological processes of the rainfall runoff formation and biogeochemical processes in the watershed, consequently, the responsiveness of the streamwater chemistry to changed hydrological states is very high. The study was carried out in 2006, within the 42 km 2 forested Padež watershed in the southwestern part of Slovenia, which is characterized by distinctive flushing, an almost torrential hydrological regime influenced by impermeable flysch geological settings. More than 15 recorded hydrographs which, in the hydrological and biogeochemical sense, differed substantially, disclosed a highly variable but at the same time a strong linkage between hydrological and biogeochemical controls of nitrate exports from the spatial perspective of a watershed.
The Reka river is the widest known sinking stream of the Classical Karst area in Slovenia, and it... more The Reka river is the widest known sinking stream of the Classical Karst area in Slovenia, and it has been studied since the Antiquity. The river sinks into the Škocjan Cave system, which was proclaimed by UNESCO as a World Heritage Site in 1986. The Reka river basin is situated in the southern part of Slovenia and has an area of 442 km2 and a mean discharge of 8.2 m3/s. The basin has a unique geological structure; it is situated on the Brkini syncline Eocene flysch rocks surrounded by a large karstic region. The stream network density is about 1.696 km/km2. The water from the northern karstic formation belongs to the Danube River Basin, while the water from the southern part drains into the Adriatic Sea. There is an underground bifurcation from which the surface water flows to the Danube River and the underground water drains in the Bistrica Spring, a tributary of the Reka River.
Proceedings of the International Association of Hydrological Sciences, 2014
IOP Conference Series: Earth and Environmental Science, 2008
Experimental watersheds are critical to the advancement of hydrological science. By setting up th... more Experimental watersheds are critical to the advancement of hydrological science. By setting up three experimental watersheds, Slovenia also obtained its grounds for further development of the science and discipline. In the Dragonja experimental watershed the studies are focused on the afforestation of the watershed in a mediterranean climate, on the Reka river the water balance in a partly karstic area is examined, and on the case of the Glinščica stream the implications of the urban environment are studied. We have obtained valuable experience and tested new measuring equipment in all three experimental watersheds.
Natural Hazards and Earth System Sciences, 2005
A medium-ranged high performance handheld reflectorless laser measurement system, was used for a ... more A medium-ranged high performance handheld reflectorless laser measurement system, was used for a morphological survey on the Strug rock fall in W Slovenia in the period from August 2003 to August 2004. The purpose was to evaluate its potential for monitoring ground surface changes in rock fall source areas and to help evaluating morphological changes by measuring distance from fixed points. In the area, 21 fixed geodetic points have been established. Altogether, seven measurement sets with more than 5500 points have been gathered in the rock fall area. Choosing a point cloud with a density of less than 1 point per 10 m 2 on a very rough rock fall surface failed to be a good solution. The changes on larger areas were shown by displacements of selected significantly large-sized rock blocks with a volume of several m 3. Because only smaller changes were observed between the single field series, the rock fall surface generally remained unchanged. Local surface changes of the order of 1 m or more, were clearly shown by measurements in the selected referenced cross sections. The usage of these cross sections gave a possibility to evaluate volumetric changes on the surface. The laser measurement system provided a good replacement for the classical terrestrial geodetic survey equipment, especially when performing remote monitoring of morphological changes in rock fall hazard zones, however, the case is different when fixed points are to be measured precisely.
The integral digital information on the waters of Slovenia is developed. This is a system of aggr... more The integral digital information on the waters of Slovenia is developed. This is a system of aggregated, verified and logically integrated information on the state of waters in Slovenia, the pressures on the water environments and its protection. Data sources are national information evidence and monitoring systems managed by public service organisations and other expert institutions. The information system is a source for planning in water management, environmental state reporting, and performance indicators evaluation. It is based on country based catchment register. The system incorporates 31 information thematic layers that are organised in the DPSIR (driving forces, pressure, state, impact, and response) system. Data for the information themes are organised with the AutoCad MAP 4.5 GIS tool and prepared for browsing with Internet.
IOP Conference Series: Earth and Environmental Science, 2008
Nowadays remote sensing data are great value for many ways of use as for snow hydrology. Snow cov... more Nowadays remote sensing data are great value for many ways of use as for snow hydrology. Snow cover mapping on basis of satellite images is widely spread because it is easier than in-situ measuring and interpolating. To verify the use of satellite imagery (MODIS product) we used all available data of snow cover and satellite images and compared detected snow