National Repository of Grey Literature 9 records found  Search took 0.00 seconds. 
Jurečka, František ; Hlavinka, Petr ; Lukas, Vojtěch ; Trnka, Miroslav ; Anderson, M. ; Hain, C. ; Balek, Jan ; Bláhová, Monika ; Žalud, Zdeněk
Actual evapotranspiration (ETa) determined by the Atmosphere-land Exchange Inverse (ALEXI) model and water balance model SoilClim was compared for selected districts of the Czech Republic. The ALEXI model uses the land surface temperature (LST) from remote sensing and provides information on ETa and subsequently the surface moisture status. The SoilClim is a dynamic model of watcr content in soil and represents a model based on water balance approach. The current version of the model is able to estimate the value of ETa, as well as soil moisture content in two layers of the soil profile. Investigated period of ETa comparison were years 2014 and 2015. Especially the year 2015 had a special relevance due to the significant summer drought that occurred in CR. Model performance was compared for the period when changes in vegetation are most significant from April to August. Week sums of ETa from both models were compared at the district level for Vysodina, JihomorayskY and Olomouck, regions. The ETa values were generally higher from ALEXI as compared to SoilClim. ALEXI values were in some cases even two or three time higher. Moreover, the seasonal dynamics showed sometimes opposite trends. As this is a pilot testing of ALEXI based ETa in the conditions of Central Europe and show large differences as compared to well established methods, more detailed testing is required prior drawing any general conclusions.
Spatial heterogeneity of selected soil properties assessed from airborne imaging spectroscopy and satellite imagery data
Zemek, František ; Pikl, Miroslav ; Lukas, Vojtěch ; Ždímal, V. ; Kraus, M. ; Širůček, P.
The methodology aims at presenting new and economically efficient approaches to assessment of spatial heterogeneity of selected properties of bare soils. There are three key features the authors paid attention: 1/the simplicity in usage with keeping sufficient accuracy, 2/data availability, 3/economic aspects allowing application to many users. The methodology covers two complementary parts. The first one gives an overview of laboratory and field soil spectroscopy. It is followed by a detail description of practical application of airborne hyperspectral and satellite multispectral data in assessment of spatial heterogeneity of bare soils. All applied methods have been developed and tested on scale of medium size farm.
Regional yield forecasting for improved decision making in the plant production
Trnka, Miroslav ; Hlavinka, Petr ; Kudláčková, Lucie ; Balek, Jan ; Meitner, Jan ; Možný, Martin ; Štěpánek, Petr ; Bartošová, Lenka ; Semerádová, Daniela ; Bláhová, Monika ; Lukas, Vojtěch ; Žalud, Zdeněk
The methodology describes how to predict yields of key crops, and at the same time addresses reliability of the predictions and how these can be used. The ability to predict yield levels more than 2 months prior the harvest on the level of regions (NUTS3¨) and districts (LAU1) brings also new opportunities to mitigate impacts of adverse conditions. The methodology shows that the yield forecasts and yield anomalies in particular are consistent and usable in practices. In this methodology, the results of 2018 yield forecasts are presented as an example. The yield forecasting system for the Czech Republic is fully functional and is and will be available through
Application of multispectral remote sensing indices for sensing indices for estimating crop yields at field level
Jurečka, František ; Lukas, Vojtěch ; Hlavinka, Petr ; Semerádová, Daniela ; Fischer, Milan ; Žalud, Zdeněk ; Trnka, Miroslav
Remote sensing can be used for yield estimation prior to harvest and can replace or complement classical\nways of estimating crop yields. This study was undertaken in Polkovice, located in the Czech Republic’s\nHaná region. For 2015 and 2016, two data sets of satellite imagery were used: the Moderate Resolution\nImaging Spectroradiometer and the Landsat 8. Vegetation indices from satellites were compared with crop\nyields at the level of land blocks. Winter wheat and spring barley yield data, representing crops planted\nover the analysed period, were used for the comparison. The results of the index–yield comparison showed\nthat vegetation indices from remote sensing data provide reliable information for yield estimation prior to\nharvest. Indices are also able to evaluate the spatial variability of a crop within the field. The results showed\nthat remote sensing data need to have detailed spatial resolution in order to provide reasonable information\nabout yield at such a detailed level.
The concept of fatherhood in the women's lifestyle magazines for different target groups defined by the level of women's income
Lukáš, Vojtěch ; Vochocová, Lenka (advisor) ; Bednařík, Petr (referee)
The thesis is focused on the role of fathers represented in different lifestyle magazines for women. There were selected two kinds of magazine brands for women from different social-economic groups. The representative magazines from higher social-economic groups were chosen Elle, Harper's Bazaar, Cosmopolitan and Marianne. The representative magazines for women from lower social-economic groups were chosen Vlasta, Chvilka pro tebe, Žena a život and Překvapení. There were found only articles which show man as father, including description, in all selected magazines. The terms were generated according to the method of open coding from each article. Then they were merged into superior categories. The final categories served as a tool for describing representation of father, as he had been described in the individual magazines. From individual magazines we moved to the whole groups of magazines, which were designed for the same social-economic groups of women. Differences and similarities in the representations of fathers were found not only between the groups but also inside of the groups themselves. Nevertheless, our work has successfully shown that there were significant differences in the descriptions of the father in the magazines for different social-economic groups of women.
Analysis of marketing campaigns of the product of the Czech Railways SC Pendolino from its launch to the market in 2005
Lukáš, Vojtěch ; Halada, Jan (referee) ; Köppl, Daniel (advisor)
Bachelor work "Analysis of marketing campaigns of the product of the Czech Railways SC Pendolino from its launch to the market in 2005" provides information about introducing the Pendolino train in the Czech Republic. What campaigns were used for this purpose and how it was presented until 2009. This work represents the communication channels and evaluates creative outputs of campaigns. To evaluate these outputs is used the semiotic analysis. Bachelor work presents concrete steps that have been used for introduction of this product to public.
Crop yield estimation in the field level using vegetation indicies
Jurečka, František ; Hlavinka, Petr ; Lukas, Vojtěch ; Trnka, Miroslav ; Žalud, Zdeněk
Remote sensing can be very useful tool for agriculture management. In this study, remote sensing methods were applied for yield estimation in the field level. There were compared remote sensing data together with yield data obtained from the field. The study area is located in Polkovice in Olomoucký region and a crop planted there in the year 2016 was spring barley as one of most important crops grown in the region. The study area in Polkovice is located at lower elevations with intensive crop production and is climatologically warmer and drier than other areas of the Czech Republic. Year 2016 was the first year when the harvest device has been used for yield analysis in this study area. The output of this method is the yield map displaying the amount of crop harvested in the particular place in the field. The yield data from the field were then compared with remote sensing data in the form of vegetation indices. Two of them were used for comparison – Normalized Difference Vegetation Index (NDVI) and a two-band Enhanced Vegetation Index (EVI2). These indices have been often used for yield estimation in different studies but mostly in larger scales. This study investigates use of NDVI and EVI2 at more detailed scale while using various remote sensing methods. Comparisons show that remote sensing data can provide accurate estimation and can be used for yield forecasting or supplement traditional ways of yield estimation. Results of the study show that yield-index correlations are stronger for satellite data than for the drone data. NDVI showed slightly stronger correlations than EVI2. Strongest correlations between vegetation indices and yields were found for NDVI from Sentinel 2.

See also: similar author names
2 Lukas, V.
4 Lukáš, Vojtěch
1 Lukáš, Vykydal
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