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Dynamics of business model in telecommunications
Filipová Fuchsová, Regina ; Malý, Josef (advisor) ; Machková, Hana (referee) ; Přikrylová, Jana (referee) ; Peterka, Jiří (referee)
This doctoral thesis is focused on the most progressive part of telecommunications nowadays, on Internet governance and Internet domain name system. This field is not only highly interesting, but only very little researched area from the point of view of economics sciences compared to the traditional fields. Recently, the question of Internet governance was highlighted, but it has been neither resolved nor sufficiently discussed so far. The theory does not answer many questions raised by the praxis sufficiently. The aim of the thesis was to describe the branch in detail and to develop an original model, which would characterise the dependency of the number of registrations on other indicators. This doctoral thesis of Regina Filipova Fuchsova brings a detailed analysis of factors influencing the domain name system. This is the first analysis of this art ever, which targets top level domains .cz and .eu. Typology of TLD registries and connection of domain name selection with the company strategy are further new findings. Based on own analysis and case studies, the author concludes, that there is a relatively strong dependency of the number of registered domains under the respective TLD on national economy characteristics and that the model of the relationship of a ccTLD registry and respective government significantly varies in particular countries. This is due to the historical development and national specifics. The author further came to the conclusion, that national and generic TLDs are partially substitutes and partially complements on national markets. It depends on concrete market and the degree of ccTLD liberalisation, because generic TLDs act as substitutes to the country code TLD on not liberalised markets and/or where the ccTLD is rather expensive. As for the liberalised markets, the growth of a ccTLD goes hand in hand with the growth of gTLD and they compete less. National TLDs of the EU countries and the European TLD .eu show the nature of complements according to the statistical analysis. There are significant theoretical and practical contributions of this work because of its wide content and original analysis in this field. The findings can be practically used for registry benchmarking and ideas related to the delegation of new top level domains.
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Monitorování rybích obsádek údolních nádrží v České republice – výsledky prvního roku sledování
Peterka, Jiří ; Čech, Martin ; Frouzová, Jaroslava ; Draštík, Vladislav ; Vašek, Mojmír ; Prchalová, Marie ; Matěna, Josef ; Kubečka, Jan ; Jůza, Tomáš ; Kratochvíl, Michal
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How shall we study the fish stock of our large water reservoirs?
Kubečka, Jan ; Matěna, Josef ; Čech, Martin ; Draštík, Vladislav ; Frouzová, Jaroslava ; Hohausová, Eva ; Jarolím, Oldřich ; Jůza, Tomáš ; Kratochvíl, Michal ; Muška, Milan ; Peterka, Jiří ; Prchalová, Marie ; Říha, Milan ; Tušer, Michal ; Vašek, Mojmír
Quantitative fish stock assessment recently advanced significantly in the Czech Republic. Sampling of open water was facilitated by application of scientific echosounders, trawls, Nordic multimesh gillnets, purse seines and booming electoshockers. Simplified combination of the above methods was recommended for the monitoring of larger stagnant water the Water Framework Directive of EU. Combination of all above approaches with more classic ones (beach seining, benthic gillnets) is being used for „complex fish stock assessment“ providing the assessment of abundance, biomass, species and age composition of all important species in all important habitats of the reservoirs. Further improvements of results is likely to be achieved by the application of multibeam acoustic cameras and by mitigation of the problems connected with quantitative trawling of large fish
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Sampling of the offshore fry fish communities of reservoirs by trawls
Jůza, Tomáš ; Kubečka, Jan ; Čech, Martin ; Draštík, Vladislav ; Jarolím, Oldřich ; Peterka, Jiří ; Vašek, Mojmír
The offshore area of six Czech reservoirs was sampled by pelagic fry trawl in late summer in 2003-2005. In Římov, Želivka, Vrané and Slapy reservoirs cyprinids dominated in offshore area. The main species here were roach, bream and bleak. In Lipno and Nýrsko reservoirs percids dominated in offshore area (Lipno-pikeperch, Nýrsko-perch). Trawling in offshore areas revealed that almost all 0+ fish were caught in the surface stratum (0-3m depth). In reservoirs where percids and cyprinids occured together, cyprinids dominated in 0-3m depth while percids usually prevailed in catches of 0+ fish from 3-6m depth. In ordinary canyon-shaped reservoir like Římov and Želivka the 0+ fish abundance decreased from the upstream end toward the dam, so the biggest abundance was in tributary area. In cascade reservoirs like Slapy and Vrané, the offshore area in tributary is almost without fish. The peak of abundance is more downstream and from this place, the trend is similiar to non-cascade reservoirs.
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Complex assessment of the fish assemblage of the Želivka reservoir, the biggest water supply reservoir in the ČR, in years 2004 and 2005
Prchalová, Marie ; Kubečka, Jan ; Jůza, Tomáš ; Říha, Milan ; Jarolím, Oldřich ; Tušer, Michal ; Peterka, Jiří ; Vašek, Mojmír
In the summer 2004 and 2005, the complex assessment of the fish assemblage of the Želivka reservoir (1432 ha) was carried out by gillnetting, adult and fry seining, adult and fry pelagic trawls and hydroacoustic sampling. Detailed picture of the fish assemblage was composed from every fishing gear from every depth strata of the open water as well as from the littoral zone. During two-years survey, 40.168 fish of 19 species and one hybrid were captured. The fish assemblage was dominated by cyprinid species in both years – bleak prevailed in the open water together with roach and bream; perch was abundant in the littoral zone. The assemblage of the Želivka reservoir was found to be in the stable cyprinid phase. The average abundance was 1.700 ind/ha and average biomass was 110 kg/ha. In the fish spatial distribution, the general gradients could be found – higher abundance and number of species in the tributary area and in the epilimnion and littoral.
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Drinking water reservoir Nýrsko - influence of macrophytes on water quality
Hejzlar, Josef ; Hohausová, Eva ; Komárková, Jaroslava ; Kopáček, Jiří ; Peterka, Jiří ; Duras, J.
The importance of macrophytes in P cycling was studied in Nýrsko Reservoir, an oligotrophic water body in western Bohemia. A comparison of the external P loading with the P content in macrophytes of Nýrsko Reservoir in 2004 demonstrated that macrophytes can play a significant role in P-cycling also in deep, pelagial-dominated water bodies on condition that the external P loading is low and macrophytes have appropriate conditions for their growth (mainly small extent of water level fluctuation). Nýrsko Reservoir is an apparent example of situations from limnological textbooks when macrophytes function as a stabilizer of the aquatic ecosystem with an efficient zooplankton grazing on phytoplankton allowing suitable water quality for drinking water production.
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Giant traps for fishing in the inflow-zone of the Římov reservoir
Hladík, Milan ; Kubečka, Jan ; Pokorný, P. ; Čech, Martin ; Draštík, Vladislav ; Kratochvíl, Michal ; Peterka, Jiří ; Prchalová, Marie ; Vašek, Mojmír
The fish stock of the inflow-zone of the Římov Reservoir was studied by using two special constructed big traps. One trap was sampling the fish migrating from the reservoir to the Malse River, the other was sampling downstream migrants. The most intensive fish movement was recorded during spring spawning season. Proportionally to the fish stock of the reservoir, the tributary zone was used mainly by the bleak, .i.Alburnus alburnus./i., Asp, .i.Aspius aspius./i. and roach .i.Rutilus rutilus./i.. Smaller affinity to tributary spawning was found for the bream .i.Abramis brama./i. and perch, .i.Perca fluviatilis./i. (5 to 10 % of reservoir fish spawning in the tributary). Over 6000 kg of migrating fish were captured in the tributary area during spring periods of three years. Consequences of the application of tributary traps for fish exploitation and management are being discussed.
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The diet of larval and juvenile pikeperch (.i.Stizostedion lucioperca./i.)(L.)), comparative study of fishponds and a reservoir
Peterka, Jiří ; Matěna, Josef ; Lipka, J.
Diet of larval and juvenile pikeperch (.i.S. lucioperca./i.) reared in ponds was investigated and compared with the diet of pikeperch from a reservoir. Numbers of rotifers were found low in the diet of pikeperch larvae in fishponds and they were soonreplaced by nauplii of cyclopoid copepods. .i.Daphnia./i. spp. were consumed from the onset of exogenous feeding. Another smaller cladoceran .i.Bosmina./i. longirostris did not contribute to the diet significantly. In the reservoir, rotifers were not found in the diet of pikeperch larvae. Dominant food items were nauplii and 1st copepodite instar of .i.Eudiaptomus gracilis./i. and .i.Cyclops./i. spp. .i.Daphnia galeata./i. and to a lesser extent .i.Diaphanosoma brachyurum./i. appeared in the pikeperch diet at a length of about 10 mm. A shift towards larger prey, especially .i.Leptodora kindtii./i., could be recognised in pikeperch at a length of 20 mm. Growth of pikeperch was found faster in nursing ponds than in the reservoir.
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