2022. augusztus 20-án olyan összetett folyamatok irányították térségünk időjárását, aminek 2022. ... more 2022. augusztus 20-án olyan összetett folyamatok irányították térségünk időjárását, aminek 2022. augusztus 20-án olyan összetett folyamatok irányították térségünk időjárását, aminek köszönhetően még a 6-18 órás időtávra szóló előrejelzést is nagy bizonytalanság jellemezte, köszönhetően még a 6-18 órás időtávra szóló előrejelzést is nagy bizonytalanság jellemezte, s az aznap estére szóló előrejelzések csak az időpont közeledtével lettek pontosabbak. Az egyes s az aznap estére szóló előrejelzések csak az időpont közeledtével lettek pontosabbak. Az egyes időjárási események és az arra vonatkozó előrejelzések értékelése nagyon fontos az adott prognózis időjárási események és az arra vonatkozó előrejelzések értékelése nagyon fontos az adott prognózis hátterének megértéséhez, valamint a modellek fejlesztéséhez. Erre került sor 2022. november 24-én hátterének megértéséhez, valamint a modellek fejlesztéséhez. Erre került sor 2022. november 24-én a Magyar Meteorológiai Társaság Légkördinamikai Szakosztályának előadó ülésén. a Magyar Meteorológiai Társaság Légkördinamikai Szakosztályának előadó ülésén. Meteorological background of the forecasts on
This article is an open access article distributed under the terms and conditions of the Creative... more This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY
The aim of this research was to develop a simulation model of the works carried out by helicopter... more The aim of this research was to develop a simulation model of the works carried out by helicopters, which are used in the construction of buildings under harsh natural conditions. This work identified that even technologies that we do not normally encounter, such as aerial work using helicopters, can have a major impact on ensuring the requirement of sustainability within the overall environmental and economic context. In the environment of protected landscape areas and national parks, in particular, where all sites are sensitive to human intervention, the use of helicopters in construction functions is an irreplaceable aid. Preparations for aerial work are very demanding and require the use of more sophisticated tools to achieve optimal results consistent within the paradigm of long-term sustainability. Simulation modeling is one such option, thanks to the considerable advancements made in information technology. A simulation model of aerial work was compiled within the presented w...
The paper presented is dedicated to the evaluation of the influence of various improvements to th... more The paper presented is dedicated to the evaluation of the influence of various improvements to the numerical weather prediction (NWP) systems exploited at the Slovak Hydrometeorological Institute (SHMÚ). The impact was illustrated in a case study with multicell thunderstorms and the results were confronted with the reference analyses from the INCA nowcasting system, regional radar reflectivity data, and METEOSAT satellite imagery. The convective cells evolution was diagnosed in non-hydrostatic dynamics experiments to study weak mesoscale vortices and updrafts. The growth of simulated clouds and evolution of the temperature at their top were compared with the brightness temperature analyzed from satellite imagery. The results obtained indicated the potential for modeling and diagnostics of small-scale structures within the convective cloudiness, which could be related to severe weather. Furthermore, the non-hydrostatic dynamics experiments related to the stability and performance imp...
The construction process is characterized by a diverse technological composition and the use of a... more The construction process is characterized by a diverse technological composition and the use of a wide range of construction machinery and mechanization. The amount of machinery increases with the complexity of the construction, which increases the demands concerning the preparation and overall organisation of the construction. The preparation of construction processes carried out by helicopters (aerial work) must respect the effect of randomly changing construction conditions as well as the specific working conditions of helicopters. The complexity of such a system can be modelled using simulation models. In the work presented, we designed and practically tested a simulation model of aerial work in the MATLAB software environment. An essential part of the simulation model is an algorithm designed on the basis of commercial numerical weather prediction models. We consider the outputs of the simulation to be reliable, because they are very close to the actual results achieved in the ...
ABSTRACT This study investigates two cases of thunderstorms with rotating characteristics, which ... more ABSTRACT This study investigates two cases of thunderstorms with rotating characteristics, which occurred in Hungary and formed in an environment of relatively low or moderate wind shear (well below 20 m/s) in the lowest 6 km layer of the troposphere. For the selected cases, the properties of the thunderstorms and their environment were examined both from observational and modeling perspectives. The observed storms showed both multicellular and supercellular features (e.g. multiple, fast developing maxima of radar reflectivity but also presence of Bounded Weak Echo Reflectivity or couplets of Doppler radar velocity extremes). Cloud-base rotation was observed by the Hungarian storm-chasers. Cloud-resolving and real-data numerical simulations with the WRF model produced generation of meso-γ-scale vortices in both mid- and low-tropospheric levels connected to convective storms. The simulated low-level vortices exhibited quasi-permanent behavior and their intensity seemed to be comparable to supercell mesocyclones. Vorticity equation terms were analyzed on the model fields in order to explain the origin of the rotation and its relation to the environmental wind shear and wind profile. The results indicated that the more transient midlevel vortices were generated via the tilting mechanism, whereas the evolution of the quasi-persistent low-level vortices was initiated by a relatively small tilting along a gust front, then they subsequently rapidly intensified by the stretching of the vertical vorticity. The storms analyzed in the model field exhibited a hybrid behavior, since the structure and evolution of the vorticity field resembled supercellular mesocyclones and mesovortices as well.
IOP Conference Series: Materials Science and Engineering, 2019
When constructing buildings on challenging terrain or in densely built urban areas, the potential... more When constructing buildings on challenging terrain or in densely built urban areas, the potential of conventional “ground” construction technology is insufficient. In this case, a building can be constructed with the assistance of helicopters. The preparation of construction processes carried out by helicopters must respect the effects of randomly changing construction conditions, mainly weather, as well as specific helicopter working conditions. Weather conditions significantly affect helicopter parameters, especially its most important value in the construction technology – the maximum load capacity. The helicopter load is therefore not constant but it “changes in time”. The complexity of this system can be modelled by using simulation models. The built-in model should allow us to investigate the behaviour of construction processes under realistic conditions and to evaluate the proposed structure of the process based on the required criteria. This presented article deals with the ...
2022. augusztus 20-án olyan összetett folyamatok irányították térségünk időjárását, aminek 2022. ... more 2022. augusztus 20-án olyan összetett folyamatok irányították térségünk időjárását, aminek 2022. augusztus 20-án olyan összetett folyamatok irányították térségünk időjárását, aminek köszönhetően még a 6-18 órás időtávra szóló előrejelzést is nagy bizonytalanság jellemezte, köszönhetően még a 6-18 órás időtávra szóló előrejelzést is nagy bizonytalanság jellemezte, s az aznap estére szóló előrejelzések csak az időpont közeledtével lettek pontosabbak. Az egyes s az aznap estére szóló előrejelzések csak az időpont közeledtével lettek pontosabbak. Az egyes időjárási események és az arra vonatkozó előrejelzések értékelése nagyon fontos az adott prognózis időjárási események és az arra vonatkozó előrejelzések értékelése nagyon fontos az adott prognózis hátterének megértéséhez, valamint a modellek fejlesztéséhez. Erre került sor 2022. november 24-én hátterének megértéséhez, valamint a modellek fejlesztéséhez. Erre került sor 2022. november 24-én a Magyar Meteorológiai Társaság Légkördinamikai Szakosztályának előadó ülésén. a Magyar Meteorológiai Társaság Légkördinamikai Szakosztályának előadó ülésén. Meteorological background of the forecasts on
This article is an open access article distributed under the terms and conditions of the Creative... more This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY
The aim of this research was to develop a simulation model of the works carried out by helicopter... more The aim of this research was to develop a simulation model of the works carried out by helicopters, which are used in the construction of buildings under harsh natural conditions. This work identified that even technologies that we do not normally encounter, such as aerial work using helicopters, can have a major impact on ensuring the requirement of sustainability within the overall environmental and economic context. In the environment of protected landscape areas and national parks, in particular, where all sites are sensitive to human intervention, the use of helicopters in construction functions is an irreplaceable aid. Preparations for aerial work are very demanding and require the use of more sophisticated tools to achieve optimal results consistent within the paradigm of long-term sustainability. Simulation modeling is one such option, thanks to the considerable advancements made in information technology. A simulation model of aerial work was compiled within the presented w...
The paper presented is dedicated to the evaluation of the influence of various improvements to th... more The paper presented is dedicated to the evaluation of the influence of various improvements to the numerical weather prediction (NWP) systems exploited at the Slovak Hydrometeorological Institute (SHMÚ). The impact was illustrated in a case study with multicell thunderstorms and the results were confronted with the reference analyses from the INCA nowcasting system, regional radar reflectivity data, and METEOSAT satellite imagery. The convective cells evolution was diagnosed in non-hydrostatic dynamics experiments to study weak mesoscale vortices and updrafts. The growth of simulated clouds and evolution of the temperature at their top were compared with the brightness temperature analyzed from satellite imagery. The results obtained indicated the potential for modeling and diagnostics of small-scale structures within the convective cloudiness, which could be related to severe weather. Furthermore, the non-hydrostatic dynamics experiments related to the stability and performance imp...
The construction process is characterized by a diverse technological composition and the use of a... more The construction process is characterized by a diverse technological composition and the use of a wide range of construction machinery and mechanization. The amount of machinery increases with the complexity of the construction, which increases the demands concerning the preparation and overall organisation of the construction. The preparation of construction processes carried out by helicopters (aerial work) must respect the effect of randomly changing construction conditions as well as the specific working conditions of helicopters. The complexity of such a system can be modelled using simulation models. In the work presented, we designed and practically tested a simulation model of aerial work in the MATLAB software environment. An essential part of the simulation model is an algorithm designed on the basis of commercial numerical weather prediction models. We consider the outputs of the simulation to be reliable, because they are very close to the actual results achieved in the ...
ABSTRACT This study investigates two cases of thunderstorms with rotating characteristics, which ... more ABSTRACT This study investigates two cases of thunderstorms with rotating characteristics, which occurred in Hungary and formed in an environment of relatively low or moderate wind shear (well below 20 m/s) in the lowest 6 km layer of the troposphere. For the selected cases, the properties of the thunderstorms and their environment were examined both from observational and modeling perspectives. The observed storms showed both multicellular and supercellular features (e.g. multiple, fast developing maxima of radar reflectivity but also presence of Bounded Weak Echo Reflectivity or couplets of Doppler radar velocity extremes). Cloud-base rotation was observed by the Hungarian storm-chasers. Cloud-resolving and real-data numerical simulations with the WRF model produced generation of meso-γ-scale vortices in both mid- and low-tropospheric levels connected to convective storms. The simulated low-level vortices exhibited quasi-permanent behavior and their intensity seemed to be comparable to supercell mesocyclones. Vorticity equation terms were analyzed on the model fields in order to explain the origin of the rotation and its relation to the environmental wind shear and wind profile. The results indicated that the more transient midlevel vortices were generated via the tilting mechanism, whereas the evolution of the quasi-persistent low-level vortices was initiated by a relatively small tilting along a gust front, then they subsequently rapidly intensified by the stretching of the vertical vorticity. The storms analyzed in the model field exhibited a hybrid behavior, since the structure and evolution of the vorticity field resembled supercellular mesocyclones and mesovortices as well.
IOP Conference Series: Materials Science and Engineering, 2019
When constructing buildings on challenging terrain or in densely built urban areas, the potential... more When constructing buildings on challenging terrain or in densely built urban areas, the potential of conventional “ground” construction technology is insufficient. In this case, a building can be constructed with the assistance of helicopters. The preparation of construction processes carried out by helicopters must respect the effects of randomly changing construction conditions, mainly weather, as well as specific helicopter working conditions. Weather conditions significantly affect helicopter parameters, especially its most important value in the construction technology – the maximum load capacity. The helicopter load is therefore not constant but it “changes in time”. The complexity of this system can be modelled by using simulation models. The built-in model should allow us to investigate the behaviour of construction processes under realistic conditions and to evaluate the proposed structure of the process based on the required criteria. This presented article deals with the ...
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