János Vágó - Academia.edu (original) (raw)

Papers by János Vágó

Research paper thumbnail of DEM based examination of pediment levels: a case study in Bükkalja, Hungary

Bükkalja is the southern pediment of Bükk Mountains. According to the geographic literature this ... more Bükkalja is the southern pediment of Bükk Mountains. According to the geographic literature this area is divided into two pediment (geomorphic) levels. Using the methods of quantitative geomorphology, the Bükkalja pilot area was examined in this paper. The main objectives of the investigation were the validation of examinations based on the digital elevation model by the accepted scientifi c achievements (referring to the dual pediment), and the analysis of the role of Miocene welded ignimbrite cuestas in the evolution of the pediment. Applying diff erent GIS based methods, the height and location of these levels were determined and their area calculated as well. Relationship was established between the location of the upper pediment level and the occurrence of welded ignimbrites on the surface. The leading role of welded ignimbrite cuestas was also confi rmed by the morphometric analysis of tuff formations.

Research paper thumbnail of DEM based morphotectonical analysis of the Kisgyőr Basin (Bükk Mts – Hungary)

Acta Montanistica Slovaca, 2021

The south-eastern part of the Bükk Mountains and the eastern side of its foothill, the Bükkalja a... more The south-eastern part of the Bükk Mountains and the eastern side of its foothill, the Bükkalja are among the less explored regions of Hungary. Based on our examinations on the field, we found that the asymmetrical valley sections, the tipped escarpments and the formation of the Kisgyőr Basin cannot be explained by the differences in the rock quality. The asymmetrical shape of these landforms and the stream captures identified in the research area indicate significant structural geological changes. In our work, we proved the asymmetry in the topography by performing swath profile analysis, and we also examined the elevation data of the areas covered by the welded ignimbrites of the Tar Dacite Tuff Formation. The results confirmed our field observations. We found that, contrary to the results of previous research, the geological structural processes played a fundamental role in the formation of the Kisgyőr Basin and its surroundings.

Research paper thumbnail of Stream Gradient Investigation in the Bükkalja Using Interpolated Surfaces

The geological, tectonic settings of an area can be examined with the analysis of drainage networ... more The geological, tectonic settings of an area can be examined with the analysis of drainage network. In the Bukkalja, the Miocene pyroclasts – mainly the welded ignimbrites – had taken decisive part in the evolution of drainage network. For the confirmation of their role, the breakpoints of stream profiles were analysed. However this method provides information only about the direct surroundings of the creeks. In the aim of getting informations about the areas between the streams, surfaces were interpolated from stream gradient data and analysed as stream gradient maps. The stream gradient data were calculated with Hack J.T.’s formula, but due to the false results it was necessary to modify this formula and to recalculate the values. According to the map interpolated from the modified stream gradient values, there is a clearly identifiable relationship between the location of the welded ignimbrites on the surface, and the gradient values. Areas with high values are on the eastern par...

Research paper thumbnail of Directional analysis of drainage network and morphotectonic features in the south-eastern part of Bükk Region

Hungarian Geographical Bulletin, 2021

The fracture deformations often result in linear morphological elements (lineaments, valleys) on ... more The fracture deformations often result in linear morphological elements (lineaments, valleys) on the surface. In many cases, the direction of the lineaments and valleys can be well followed by the strike of the geological structural elements. Therefore, conclusions can be drawn from these directions for regional tectonic processes. Our work aimed to analyse the relationship between the valley and lineament network and the structural elements in the south-eastern part of Bükk Region. We prepared the theoretical drainage network map and lineament map of the area. The direction of the linear elements was examined separately on the eastern part of South-Eastern Bükk that is built up mainly by Mesozoic limestone and the eastern side of Bükkalja area covered by Neogene and Quaternary sediments. Structural geological surveys were also performed on seven sites to measure the strike of joint sets. These results were compared with the valleys’ direction in the 2 km wide area of the measuremen...

Research paper thumbnail of Landslide susceptibility mapping using GIS-based multi-criteria decision analysis, support vector machines, and logistic regression

Landslides, 2013

This research presents the results of the GIS-based statistical models for generation of landslid... more This research presents the results of the GIS-based statistical models for generation of landslide susceptibility mapping using geographic information system (GIS) and remote-sensing data for Cameron Highlands area in Malaysia. Ten factors including slope, aspect, soil, lithology, NDVI, land cover, distance to drainage, precipitation, distance to fault, and distance to road were extracted from SAR data, SPOT 5 and WorldView-1 images. The relationships between the detected landslide locations and these ten related factors were identified by using GIS-based statistical models including analytical hierarchy process (AHP), weighted linear combination (WLC) and spatial multi-criteria evaluation (SMCE) models. The landslide inventory map which has a total of 92 landslide locations was created based on numerous resources such as digital aerial photographs, AIRSAR data, WorldView-1 images, and field surveys. Then, 80% of the landslide inventory was used for training the statistical models and the remaining 20% was used for validation purpose. The validation results using the Relative landslide density index (R-index) and Receiver operating characteristic (ROC) demonstrated that the SMCE model (accuracy is 96%) is better in prediction than AHP (accuracy is 91%) and WLC (accuracy is 89%) models. These landslide susceptibility maps would be useful for hazard mitigation purpose and regional planning. D estructive outcomes of landslides in relation to human life and the overall economic system of many nations around the globe are very severe 1. Landslide hazard assessment and risk reduction can be accomplished by providing risk managers with easily accessible, continuous, and accurate information about landslide occurrence 2. Thus, an accurate susceptibility mapping can be key information for a large variety of users from both private and public sectors, from governmental departments and the scientific community on both local and international levels 3. Recently, landslide susceptibility mapping has been made possible due to the accessibility and variety of remote sensing data and thematic layers as causative factors data using GIS 4-6. Most of these landslides are referred to as significant geomorphic processes which usually form an important landscaping aspect in humid tropical mountain surroundings 7. Records have shown that in Southeast Asia, steep hill slopes, seasonally dry periods, excessive rainfall intensities, and unstable soils are the main causes of frequent landslides 8. In Cameron highlands, landslide mapping is difficult since the landslides are generally covered by dense vegetation. In addition the cloudy and rainy weather conditions are often undesirable for optical remote sensing data 9. Consequently, it is necessary that new techniques and accurate data are used in landslide susceptibility mapping in the tropical environment. In recent years, radar has added a new dimension to disaster management research by providing real-time and precise information. Synthetic aperture radar (SAR) is an active remote sensing system which has the capability of data collection day and night under all weather conditions 10. In recent years, SAR data are increasingly applied to natural hazards' researches, either by themselves or in combination with data from other remote sensing sensors 11. SAR data such as amplitude and SAR polarimetric (POLSAR) images, interferometric DEM and other products of the interferometric DEM have proven useful. The combination of both optical and SAR data can also be utilized in geo-hazards identification and mapping to complement analysis. The SAR technique is highly popular in landslide studies 12. Thus, remote sensing can play a role in the production of a landslide inventory map and in the generation of thematic maps related to landslide occurrences. Several previous works have showed the potential of remotesensing data both in the extraction of causal factors which are linked to landslide occurrences and finding of

Research paper thumbnail of Flood- and Logistical Modeling in the Hernád Watershed

The article presents the aims and preliminary results of the SKHU/1601/4.1/187 "Floodresc" Hungar... more The article presents the aims and preliminary results of the SKHU/1601/4.1/187 "Floodresc" Hungarian-Slovakian joint project. This project includes flood modeling to predict the size and location of the flooded area, the analysis of effects of floods on the natural and human environment, the optimization and planning of logistic tasks carried out by the disaster management authorities, and the handling of public health and epidemic effects of floods. The target area is the Hernád/Hornád watershed. The expected results of the project will ensure prompt data and information to support the decision making of disaster management authorities, and provide a potentially secure environment for the inhabitants and local enterprises. The flood modeling tool-on the basis of a GIS database-will be capable to predict the extent of flooded area occurred by a potential dam failure. On the basis of the database and outputs of flood modeling tool, a logistical modeling tool will be developed to optimize and plan the logistics tasks and activities (e.g. transportation, evacuation). An environmental impact assessment study and a disaster-medicine protocol will be elaborated as well to manage better the public health and epidemic effects of floods.

Research paper thumbnail of The characteristics of tourism in the Telekes valley area

This paper presents a small and less-known sight of geotourism in the famous Aggteleki Karst regi... more This paper presents a small and less-known sight of geotourism in the famous Aggteleki Karst region: the valley of Telekes creek and the settlements in its neighbourhood from touristic point of view. The gorge like valley of Telekes creek is located in the Rudabánya Hills, NE Hungary, which is one of the most spectacular sights in the region. The surroundings of the valley also have numerous interesting attractions for visitors, where small settlements and other geotouristic destinations can be found. The diverse touristic characteristics of the villages around the valley were also analysed, especially the number of tourism accommodations and the duration of stay in the region.

Research paper thumbnail of Floodresc - árvízi katasztrófahelyzetek kezelése a Hernád vízgyűjtőben

International Journal of Engineering and Management Sciences, 2019

A Floodresc projekt célja egy olyan térinformatikai döntéstámogató rendszer kifejlesztése, amely ... more A Floodresc projekt célja egy olyan térinformatikai döntéstámogató rendszer kifejlesztése, amely a Hernád folyó esetleges árvizei során segítheti a megyei katasztrófavédelmi igazgatóság védekezési, mentési feladatait. A döntéstámogató rendszer főbb elemei a teljes vízgyűjtőt lefedő térinformatikai adatbázis, az elöntött területek kiterjedését időben előre jelző, modellező alkalmazás, amelyekre a védekezéshez kapcsolódó szállítási feladatokat támogató logisztikai tervező eszköz épül.

Research paper thumbnail of DEM based examination of pediment levels: a case study in Bükkalja, Hungary

Bükkalja is the southern pediment of Bükk Mountains. According to the geographic literature this ... more Bükkalja is the southern pediment of Bükk Mountains. According to the geographic literature this area is divided into two pediment (geomorphic) levels. Using the methods of quantitative geomorphology, the Bükkalja pilot area was examined in this paper. The main objectives of the investigation were the validation of examinations based on the digital elevation model by the accepted scientifi c achievements (referring to the dual pediment), and the analysis of the role of Miocene welded ignimbrite cuestas in the evolution of the pediment. Applying diff erent GIS based methods, the height and location of these levels were determined and their area calculated as well. Relationship was established between the location of the upper pediment level and the occurrence of welded ignimbrites on the surface. The leading role of welded ignimbrite cuestas was also confi rmed by the morphometric analysis of tuff formations.

Research paper thumbnail of DEM based morphotectonical analysis of the Kisgyőr Basin (Bükk Mts – Hungary)

Acta Montanistica Slovaca, 2021

The south-eastern part of the Bükk Mountains and the eastern side of its foothill, the Bükkalja a... more The south-eastern part of the Bükk Mountains and the eastern side of its foothill, the Bükkalja are among the less explored regions of Hungary. Based on our examinations on the field, we found that the asymmetrical valley sections, the tipped escarpments and the formation of the Kisgyőr Basin cannot be explained by the differences in the rock quality. The asymmetrical shape of these landforms and the stream captures identified in the research area indicate significant structural geological changes. In our work, we proved the asymmetry in the topography by performing swath profile analysis, and we also examined the elevation data of the areas covered by the welded ignimbrites of the Tar Dacite Tuff Formation. The results confirmed our field observations. We found that, contrary to the results of previous research, the geological structural processes played a fundamental role in the formation of the Kisgyőr Basin and its surroundings.

Research paper thumbnail of Stream Gradient Investigation in the Bükkalja Using Interpolated Surfaces

The geological, tectonic settings of an area can be examined with the analysis of drainage networ... more The geological, tectonic settings of an area can be examined with the analysis of drainage network. In the Bukkalja, the Miocene pyroclasts – mainly the welded ignimbrites – had taken decisive part in the evolution of drainage network. For the confirmation of their role, the breakpoints of stream profiles were analysed. However this method provides information only about the direct surroundings of the creeks. In the aim of getting informations about the areas between the streams, surfaces were interpolated from stream gradient data and analysed as stream gradient maps. The stream gradient data were calculated with Hack J.T.’s formula, but due to the false results it was necessary to modify this formula and to recalculate the values. According to the map interpolated from the modified stream gradient values, there is a clearly identifiable relationship between the location of the welded ignimbrites on the surface, and the gradient values. Areas with high values are on the eastern par...

Research paper thumbnail of Directional analysis of drainage network and morphotectonic features in the south-eastern part of Bükk Region

Hungarian Geographical Bulletin, 2021

The fracture deformations often result in linear morphological elements (lineaments, valleys) on ... more The fracture deformations often result in linear morphological elements (lineaments, valleys) on the surface. In many cases, the direction of the lineaments and valleys can be well followed by the strike of the geological structural elements. Therefore, conclusions can be drawn from these directions for regional tectonic processes. Our work aimed to analyse the relationship between the valley and lineament network and the structural elements in the south-eastern part of Bükk Region. We prepared the theoretical drainage network map and lineament map of the area. The direction of the linear elements was examined separately on the eastern part of South-Eastern Bükk that is built up mainly by Mesozoic limestone and the eastern side of Bükkalja area covered by Neogene and Quaternary sediments. Structural geological surveys were also performed on seven sites to measure the strike of joint sets. These results were compared with the valleys’ direction in the 2 km wide area of the measuremen...

Research paper thumbnail of Landslide susceptibility mapping using GIS-based multi-criteria decision analysis, support vector machines, and logistic regression

Landslides, 2013

This research presents the results of the GIS-based statistical models for generation of landslid... more This research presents the results of the GIS-based statistical models for generation of landslide susceptibility mapping using geographic information system (GIS) and remote-sensing data for Cameron Highlands area in Malaysia. Ten factors including slope, aspect, soil, lithology, NDVI, land cover, distance to drainage, precipitation, distance to fault, and distance to road were extracted from SAR data, SPOT 5 and WorldView-1 images. The relationships between the detected landslide locations and these ten related factors were identified by using GIS-based statistical models including analytical hierarchy process (AHP), weighted linear combination (WLC) and spatial multi-criteria evaluation (SMCE) models. The landslide inventory map which has a total of 92 landslide locations was created based on numerous resources such as digital aerial photographs, AIRSAR data, WorldView-1 images, and field surveys. Then, 80% of the landslide inventory was used for training the statistical models and the remaining 20% was used for validation purpose. The validation results using the Relative landslide density index (R-index) and Receiver operating characteristic (ROC) demonstrated that the SMCE model (accuracy is 96%) is better in prediction than AHP (accuracy is 91%) and WLC (accuracy is 89%) models. These landslide susceptibility maps would be useful for hazard mitigation purpose and regional planning. D estructive outcomes of landslides in relation to human life and the overall economic system of many nations around the globe are very severe 1. Landslide hazard assessment and risk reduction can be accomplished by providing risk managers with easily accessible, continuous, and accurate information about landslide occurrence 2. Thus, an accurate susceptibility mapping can be key information for a large variety of users from both private and public sectors, from governmental departments and the scientific community on both local and international levels 3. Recently, landslide susceptibility mapping has been made possible due to the accessibility and variety of remote sensing data and thematic layers as causative factors data using GIS 4-6. Most of these landslides are referred to as significant geomorphic processes which usually form an important landscaping aspect in humid tropical mountain surroundings 7. Records have shown that in Southeast Asia, steep hill slopes, seasonally dry periods, excessive rainfall intensities, and unstable soils are the main causes of frequent landslides 8. In Cameron highlands, landslide mapping is difficult since the landslides are generally covered by dense vegetation. In addition the cloudy and rainy weather conditions are often undesirable for optical remote sensing data 9. Consequently, it is necessary that new techniques and accurate data are used in landslide susceptibility mapping in the tropical environment. In recent years, radar has added a new dimension to disaster management research by providing real-time and precise information. Synthetic aperture radar (SAR) is an active remote sensing system which has the capability of data collection day and night under all weather conditions 10. In recent years, SAR data are increasingly applied to natural hazards' researches, either by themselves or in combination with data from other remote sensing sensors 11. SAR data such as amplitude and SAR polarimetric (POLSAR) images, interferometric DEM and other products of the interferometric DEM have proven useful. The combination of both optical and SAR data can also be utilized in geo-hazards identification and mapping to complement analysis. The SAR technique is highly popular in landslide studies 12. Thus, remote sensing can play a role in the production of a landslide inventory map and in the generation of thematic maps related to landslide occurrences. Several previous works have showed the potential of remotesensing data both in the extraction of causal factors which are linked to landslide occurrences and finding of

Research paper thumbnail of Flood- and Logistical Modeling in the Hernád Watershed

The article presents the aims and preliminary results of the SKHU/1601/4.1/187 "Floodresc" Hungar... more The article presents the aims and preliminary results of the SKHU/1601/4.1/187 "Floodresc" Hungarian-Slovakian joint project. This project includes flood modeling to predict the size and location of the flooded area, the analysis of effects of floods on the natural and human environment, the optimization and planning of logistic tasks carried out by the disaster management authorities, and the handling of public health and epidemic effects of floods. The target area is the Hernád/Hornád watershed. The expected results of the project will ensure prompt data and information to support the decision making of disaster management authorities, and provide a potentially secure environment for the inhabitants and local enterprises. The flood modeling tool-on the basis of a GIS database-will be capable to predict the extent of flooded area occurred by a potential dam failure. On the basis of the database and outputs of flood modeling tool, a logistical modeling tool will be developed to optimize and plan the logistics tasks and activities (e.g. transportation, evacuation). An environmental impact assessment study and a disaster-medicine protocol will be elaborated as well to manage better the public health and epidemic effects of floods.

Research paper thumbnail of The characteristics of tourism in the Telekes valley area

This paper presents a small and less-known sight of geotourism in the famous Aggteleki Karst regi... more This paper presents a small and less-known sight of geotourism in the famous Aggteleki Karst region: the valley of Telekes creek and the settlements in its neighbourhood from touristic point of view. The gorge like valley of Telekes creek is located in the Rudabánya Hills, NE Hungary, which is one of the most spectacular sights in the region. The surroundings of the valley also have numerous interesting attractions for visitors, where small settlements and other geotouristic destinations can be found. The diverse touristic characteristics of the villages around the valley were also analysed, especially the number of tourism accommodations and the duration of stay in the region.

Research paper thumbnail of Floodresc - árvízi katasztrófahelyzetek kezelése a Hernád vízgyűjtőben

International Journal of Engineering and Management Sciences, 2019

A Floodresc projekt célja egy olyan térinformatikai döntéstámogató rendszer kifejlesztése, amely ... more A Floodresc projekt célja egy olyan térinformatikai döntéstámogató rendszer kifejlesztése, amely a Hernád folyó esetleges árvizei során segítheti a megyei katasztrófavédelmi igazgatóság védekezési, mentési feladatait. A döntéstámogató rendszer főbb elemei a teljes vízgyűjtőt lefedő térinformatikai adatbázis, az elöntött területek kiterjedését időben előre jelző, modellező alkalmazás, amelyekre a védekezéshez kapcsolódó szállítási feladatokat támogató logisztikai tervező eszköz épül.