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542. Český lid | 2010 Volume:97 | Number:4
- Type:
- model:periodicalitem and TEXT
- Language:
- Czech, Slovak, and English
- Description:
- 4
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
543. Cesta k pokusu o spoločenskú reformu roku 1968 /
- Creator:
- Zudová-Lešková, Zlatica,
- Type:
- text and zprávy z vědeckého života
- Subject:
- Dějiny Česka a Slovenska, konference vědecké, and zahraniční konference, kongresy
- Language:
- Slovak
- Description:
- Krpáčov, 9. - 10. 6. 1998
- Rights:
- unknown
544. Cesta ke Květnu :
- Type:
- text and dokumenty
- Subject:
- Dějiny Česka a Slovenska, válka druhá světová (1939-1945), Československo 1938-1945, and politické dějiny, politici
- Language:
- Czech and Slovak
- Rights:
- unknown
545. Cesta ke Květnu :
- Type:
- text and dokumenty
- Subject:
- Dějiny Česka a Slovenska, osvobození Československa, povstání české květnové (1945), Československo 1938-1945, and politické dějiny, politici
- Language:
- Czech and Slovak
- Rights:
- unknown
546. Čeština ako literárny jazyk na Slovensku v období národného obrodenia /
- Creator:
- Vojtech, Miloslav,
- Type:
- text and studie
- Subject:
- Čeština, národní obrození, jazyk český, literatura českojazyčná, Slovensko 1780-1847, and literatura, spisovatelé
- Language:
- Slovak
- Rights:
- unknown
547. CFD simulation of flow behind overflooded obstacle
- Creator:
- Velísková, Yvetta, Chára, Zdeněk, Schügerl, Radoslav, and Dulovičová, Renáta
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- velocity profile, computational fluid dynamics (CFD), free surface flow, bridge, ADV, laboratory flume, numerical simulation, and RANS models
- Language:
- Slovak
- Description:
- This paper deals with studying of two topics – measuring of velocity profile deformation behind a over-flooded construction and modelling of this velocity profile deformation by computational fluid dynamics (CFD). Numerical simulations with an unsteady RANS models - Standard k-ε, Realizable k-ε, Standard k-ω and Reynolds stress models (ANSYS Fluent v.18) and experimental measurements in a laboratory flume (using ADV) were performed. Results of both approaches showed and affirmed presence of velocity profile deformation behind the obstacle, but some discrepancies between the measured and simulated values were also observed. With increasing distance from the obstacle, the differences between the simulation and the measured data increase and the results of the numerical models are no longer usable.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
548. Change of Žitný Ostrov channel network aggradation state
- Creator:
- Dulovičová, Renáta and Velísková, Yvetta
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- Rye Island, bed silts, channel network, field measurement, Žitný Ostrov, dnové nánosy, kanálová sieť, and terénne merania
- Language:
- Slovak
- Description:
- The channel network at this region was built up for drainage and also to provide irrigation water. The water level in the whole channel network system affect groundwater level and viceverse. From the view of mutual interaction between channel network and groundwater it has been necessary to assess impact of channel network silting on this interaction. The measurements of thickness of silts along three main channels were carried out in 1993. Then in 2004 there were done measurements in selected profiles along three channels: Aszód, Gabčíkovo-Topoľníky and Komárňanský channel. The paper shows changes in measured thickness and volume of silt in particular channels. It was shown the channel silting up has not been changed significantly during the monitored period. This fact is documented by graphical presentation of silt thicknesses of channels. The differences between silt top and channel bottom levels are presented. and Obsahom príspevku je hodnotenie zmien stavu kanálovej siete Žitného Ostrova z hľadiska zanesenia kanálov dnovými nánosmi v období rokov 1993 až 2004. Kanálová sieť bola vybudovaná v tomto regióne v priebehu 19. storočia jednak na čiastočné odvodnenie územia a zároveň na zabezpečenie závlah. Hladina vody v kanáloch ovplyvňuje výšku hladiny podzemnej vody v ich okolí a naopak. Z hľadiska procesu vzájomnej interakcie kanálovej siete s okolitou podzemnou vodou je nevyhnutné venovať pozornosť vplyvu zanášania kanálov dnovými nánosmi, keďže tieto môžu v značnej miere tento proces ovplyvňovať. V roku 1993 boli merané zanesenia kanálovej siete ŽO na vopred stanovených priečnych profiloch niektorých hlavných kanálov. V priebehu rokov 2004 boli vykonané kontrolné merania zanesenia vo vybraných profiloch kanálov Aszód, Gabčíkovo-Topoľníky a Komárňanského kanála. Tieto kontrolné merania sa robili vždy v úseku na začiatku, v strede a na konci jednotlivých kanálov, pretože sa uvažovalo s predpokladom lineárnych zmien hrúbok nánosov pozdĺž kanálov. Grafickými prílohami príspevok dokumentuje skutočnosť, že v priebehu sledovaného obdobia nedošlo k podstatným zmenám zanesenia kanálovej siete. Keďže pre účely príspevku sú dôležité hrúbky nánosov (teda rozdiely medzi dnom kanála a vrchom nánosovej vrstvy), bolo postačujúce, aby kontrolné merania boli robené od hladiny a neboli vztiahnuté na nadmorské výšky.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
549. Changes in direct CO2 and N2O emissions from a loam Haplic Luvisol under conventional moldboard and reduced tillage during growing season and post-harvest period of red clover
- Creator:
- Horák, Ján, Igaz, Dušan, Aydin, Elena, Šimanský, Vladimír, Buchkina, Natalya, and Balashov, Eugene
- Format:
- počítač and online zdroj
- Type:
- model:article and TEXT
- Subject:
- tillage systems, soil organic matter, temperature, moisture content, water-filled pore space, and CO2 and N2O emissions
- Language:
- Slovak
- Description:
- The objectives of the study were to: (1) assess the strength of associations of direct CO2 and N2O emissions with the seasonal variations in the relevant soil properties under both tillage systems; 2) evaluate how CT and RT affect magnitudes of seasonal CO2 and N2O fluxes from soil. Field studies were carried out on plots for conventional tillage (up to 0.22–0.25 m) and reduced tillage (up to 0.10–0.12 m) during the growing season and post-harvest period of red clover. The results showed that daily CO2 emissions significantly correlated only with soil temperature during the growing season under conventional and reduced tillage. Soil temperature demonstrated its highest influence on daily N2O emissions only at the beginning of the growing season in both tillage systems. There were no significant inter-system differences in daily CO2 and N2O emissions from soil during the entire period of observations. Over the duration of post-harvest period, water-filled pore space was a better predictor of daily CO2 emissions from soils under CT and RT. The conventional and reduced tillage did not cause significant differences in cumulative N2O and CO2 fluxes from soil.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
550. Changes in runoff in two neighbouring catchments in the Bohemian Forest related to climate and land cover changes
- Creator:
- Bernsteinová, Jana, Bässler, Claus, Zimmermann, Lothar, Langhammer, Jakub, and Beudert, Burkhard
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- runoff, climate change, and forest disturbance
- Language:
- Slovak
- Description:
- There is public concern that large-scale disturbances to forest cover caused by insects and storm winds in the Bohemian Forest could intensify high water flows and enhance the expected flooding risks predicted in current regional climate change scenarios. We analysed stream discharge in Upper Vydra and Große Ohe, neighbouring catchments in the Bohemian Forest, the largest contiguous forested area in Central Europe. Upper Vydra, in the Šumava National Park, and Große Ohe (including the Upper Große Ohe headwater catchment in the Bavarian Forest National Park) are similar in size, but differ in land use cover and the extent of disturbed Norway spruce stands. Publicly available runoff and meteorological data (1978-2011) were examined using non-parametric trend and breakpoint analysis. Together with mapped vegetation cover changes, the results were used to address the following questions: 1) are there significant changes in the hydrological cycle and, if so, do these changes relate to 2) the extent and expansion of disturbance in forests stands and/or 3) altered precipitation dynamics and thermal conditions? We found no marked overall change in annual runoff or in annual or seasonal precipitation, but a significant increase in high flows in March. This overall trend related to the marked warming in late winter and early spring (+~4 K in April, p < 0.01), irrespective of altitude and slope position. It significantly shifted the end of the snow cover period by more than three weeks to the beginning/middle of April depending on altitude, and intensified snow melt. In the Upper Große Ohe catchment, a significant decrease in catchment balance, the difference between the long term precipitation and runoff (-72 mm, 11%) was found when the loss of tree cover reached 30% of catchment area. Diminished evapotranspiration losses from severely disturbed stands increased groundwater recharge during summer and caused a significant rise in low flows in autumn. However, observed increases in late winter high flows were due to warming only. They could be further intensified by the increasing winter precipitation predicted under present climate change scenarios, and would therefore increase the risk of flooding at lower elevations.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public