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First results of experimental investigation in frequency band 58 GHz
Kvičera, V.; Grábner, M.; Fišer, Ondřej
2002 - Czech
TESTCOM and Institute of Atmospheric Physics, ASCR launched a common experimental research in the frequency band 58 GHz on the experimental hop Geophysical Institute, ASCR - TESTCOM in the frequency band 58 GHz since December 2000. Our research has been focused on obtaining knowledge concerning attenuation due to hydrometeors in our specific climatic conditions. The path length is 846 m, used frequency is 57 650 MHz with V polarization. Records of received signal were statistical processed and cumulative distributions of attenuation due to hydrometeors for individual month as well as the first year period of observation from December 2000 to November 2001 were obtained. The records of attenuation were compared with the concurrent meteorological situation and attenuation due to rain, snow, fog, rain with snow and rain with hail were separatd. Rain intensities have been measured at both sites of path. Obtained CDs of rain intensities are presented. TESTCOM ve spolupráci s Ústavem fyziky atmosféry AV ČR zahájil v prosinci 2000 experimentální průzkum šíření elektromagnetických vln v kmitočtovém pásmu 58 GHz na experimentálním skoku Geofyzikální ústav AV ČR Praha - TESTCOM. Průzkum je zaměřen na získání znalostí o únicích způsobených hydrometeory v tomto kmitočtovém pásmu v našich klimatickýchpodmínkách. Skok je dlouhý 846 m, kmitočet je 57 650 MHz a polarizace je vertikální.
Keywords:
rain measurement; rain attenuation; radiowave propagation
Available at various institutes of the ASCR
First results of experimental investigation in frequency band 58 GHz
TESTCOM and Institute of Atmospheric Physics, ASCR launched a common experimental research in the frequency band 58 GHz on the experimental hop Geophysical Institute, ASCR - TESTCOM in the frequency ...
Drop size distribution applied to microwaves
Fišer, Ondřej
2001 - Czech
This study shows the global influence of the atmosphere (rain, cloud, water vapour) on the attenuation of radio waves. Selected models predicting the atmospheric attenuation are shown. Studie podává přehled účinků atmosféry (dešť, oblaka, vodní pára) na útlum radiových vln. Ukazány jsou vybrané modely predikující útlum atmosferou..
Keywords:
radio wave propagation; atmospheric attenuation; drop size distribution
Available at various institutes of the ASCR
Drop size distribution applied to microwaves
This study shows the global influence of the atmosphere (rain, cloud, water vapour) on the attenuation of radio waves. Selected models predicting the atmospheric attenuation are shown.
Ionospheric effects of Solar eclipse 11.8. 1999
Boška, Josef; Šauli, Petra; Burešová, Dalia
2001 - Czech
Ionospheric response to Solar eclipse of 11.8.1999 was observed by ionospheric vertical sounding at Pruhonice observatory. One minute ionograms have been taken to evaluate changes of the main ionospheric characteristics and wave effects during this unique phenomenon. Ionosférické účinky slunečního zatmění 11.8.1999 byly pozorovány na observatoři Průhonice metodou ionosférických vertikálních sondáží. Ionogramy, získané každou minutu v průběhu zatmění, umožňují sledovat rychlé změny hlavních ionosférických charakteristik a vlnové efekty v průběhu tohoto mimořádného jevu.
Keywords:
solar eclipse; solar terminator; gravity wave
Available at various institutes of the ASCR
Ionospheric effects of Solar eclipse 11.8. 1999
Ionospheric response to Solar eclipse of 11.8.1999 was observed by ionospheric vertical sounding at Pruhonice observatory. One minute ionograms have been taken to evaluate changes of the main ...
Wave effects in the electron concentration in the ionospheric F-layer during geomagnetic quiet conditions
Šauli, Petra; Boška, Josef
2001 - Czech
The Earth's atmosphere supports wide range of wave like movements so called atmospheric waves. The observed acoustic gravity waves during geomagnetically quiet conditions are dominantly of tropospheric or stratospheric origin. Zemská atmosféra je prostředím vhodným pro šíření různých typů vlnových pohybů, souhrnně nazývaných atmosférické vlny. Aktivita akusticko gravitačních vln v období nízké geomagnetické aktivity, zjištěné na výsledcích ionosférické vertikální sondáže, je dána především průchodem GW troposférického či stratosférického původu.
Keywords:
ionosphere; acoustic gravity wave
Available at various institutes of the ASCR
Wave effects in the electron concentration in the ionospheric F-layer during geomagnetic quiet conditions
The Earth's atmosphere supports wide range of wave like movements so called atmospheric waves. The observed acoustic gravity waves during geomagnetically quiet conditions are dominantly of ...
Research on possible climate change impacts
Huth, Radan; Dubrovský, Martin; Žalud, Z.; Šťastná, M.; Trnka, M.; Hejzlar, Josef; Buchtele, Josef; Růžička, Martin; Kalvová, J.; Nemešová, Ivana
2001 - Czech
Brief information about the projects on climate change impact research running at the Academy of Sciences. Their common part is the construction of climate change scenarios for experimental sites. Cilem tohoto příspěvku je stručná informace o projektech výzkumu dopadů změny klimatu, které v současné době probíhají v AV ČR a spolupracujících institucích a které koordinuje Ústav fyziky atmosféry AV ČR (ÚFA). Jedná se o dva multidisciplinární projekty, řešené v období 1999-2001. Jejich společnou částí je konstrukce scénářů klimatické změny pro experimentální lokality, řešená na ÚFA AV ČR a Katedře meteorologie a ochrany prostředí MFF UK.
Keywords:
climate; climate change; climate change impacts
Available at various institutes of the ASCR
Research on possible climate change impacts
Brief information about the projects on climate change impact research running at the Academy of Sciences. Their common part is the construction of climate change scenarios for experimental sites.
Long term trends in ionosphere
Laštovička, Jan
2001 - Czech
The greenhouse effect causes long-term changes and trends in the troposphere and also at higher levels including the ionosphere. Here an overview of such effects is given. Skleníkový efekt vyvolává dlouhodobé trendy změn nejen v troposféře, ale i v ionosféře. Zde je podán jejich přehled.
Keywords:
long-term trends; ionosphere; greenhouse effect
Available at various institutes of the ASCR
Long term trends in ionosphere
The greenhouse effect causes long-term changes and trends in the troposphere and also at higher levels including the ionosphere. Here an overview of such effects is given.
Deterministic and statistical estimates of probable precipitation amounts for the territory of the Czech Republic
Řezáčová, Daniela; Sokol, Zbyněk; Pešice, Petr
2001 - Czech
Two methods were developed to estimate PPM (Probable maximum precipitation). For the interval 1-12 hours the dynamical-statistical model was applied. For longer intervals the statistical model was used. Byly vyvinuty dvě metody pro odhad PPM (pravděpodobná maximální srážka) s různou delkou trvaní srážky. První dynamicko-statistická metoda byla vyvinuta pro srážkové úhrny do 12 hodin. Pro úhrny nad 12 hodin byla vyvinuta statistická metoda.
Keywords:
Probable maximum precipitation; flood; extreme precipitation
Available at various institutes of the ASCR
Deterministic and statistical estimates of probable precipitation amounts for the territory of the Czech Republic
Two methods were developed to estimate PPM (Probable maximum precipitation). For the interval 1-12 hours the dynamical-statistical model was applied. For longer intervals the statistical model was ...
Height profil of geomagnetic storm effects in the ionosphere and atmosphere
Laštovička, Jan
2000 - Czech
The construction of the height profile of the geomagnetic storm effects in the ionosphere and atmosphere is described. In the F2 region the ionospheric effect is strong and is a response to thermospheric storm. In the lower ionosphere, the strong effect is a direct consequence of a substantial increase of flux of precipitating high energy particles. In the lower atmosphere the origin of strom effects is different. Popisuje se konstrukce výškového profilu efektu geomagnetických bouří v ionosféře a atmosféře. V F2 vrstvě je ionosférický efekt silný a je odezvou na termosférickou bouři, v dolní ionosféře je silný efekt přímým následkem vzrůstu intenzity vysypávajících se energetických částic, v dolní atmosféře pak má příčinu odlišnou.
Available at various institutes of the ASCR
Height profil of geomagnetic storm effects in the ionosphere and atmosphere
The construction of the height profile of the geomagnetic storm effects in the ionosphere and atmosphere is described. In the F2 region the ionospheric effect is strong and is a response to ...
Gödel's incompleteness theorema and its meaning for a modern science
Horák, Jiří; Krlín, Ladislav
2000 - Czech
Gödel's results of the logical systems incompleteness was discussed. Pomocí Gödelových výsledků problému o neúplnosti logických systémů byla posuzována úloha o prokázání stochastičnosti dynamických systémů.
Available at various institutes of the ASCR
Gödel's incompleteness theorema and its meaning for a modern science
Gödel's results of the logical systems incompleteness was discussed.
Application of modern managerial methods in managing a scientific institute
Laštovička, Jan
2000 - Czech
The application of methods based on brainstorming and methods of time management in managing scientific institute and in the work of individual scientists is described. Popisují se aplikace metod založených na braistorming a metod hospodaření s časem v řízení vědeckého ústavu a v práci jednotlivých vědeckých pracovníků.
Available at various institutes of the ASCR
Application of modern managerial methods in managing a scientific institute
The application of methods based on brainstorming and methods of time management in managing scientific institute and in the work of individual scientists is described.
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