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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Vliv orientace svahu na sezónní růst stromů v ekotonu horní hranice lesa / Effect of slope aspect on intra-annual growth of trees in the treeline

Zákravská, Šárka January 2013 (has links)
This diploma thesis is focused on microclimatic differences at treelines on north-facing and south-facing slopes and their effect on tree growth. Thesis contains an overview of factors affecting development and timing of xylogenesis. The effects of slope orientation on treeline in relation to exposure effect are mentioned as well. The aim of the practical part of diploma thesis was to determine development, timing and the impact of temperature characteristics on xylogenesis of Norway spurce (Picea abies) on two localities with opposite slope aspect. Locations were situated in the Důl Bílého Labe valley, Krkonoše Mountains. Xylogenesis was studied using sections of micro-cores. Microcores were sampled every 10 days during the growing season. They were subsequently analyzed in dendrochronological laboratory. My results show that influence of air temperature recorded at the start of cambial cell division and the development of enlarging cells in the first part of the growing season. Climatic characteristics of both sites was similar, larger differences in temperatures were recorded at the beginning and at the end of the reference period.
2

Automatizace pěstebního procesu z hlediska programového řízení teploty a vlhkosti vzduchu / Automation of the cultivation process in term of program control of temperature and moisture

Beneš, Vojtěch January 2016 (has links)
Theoretical part of this thesis describes different kinds of sensors used for measuring temperature and humidity of air. These sensors are categorized according to the principle on which they operate. It also describes their characteristics like range, accuracy and other aspects important for determining suitability for a glasshouse automation system. Practical part of this work covers design of this system which can be used for auto-mated controll over temperature and humidity. It reasons about suitability of different kinds of sensors and materials. It also describes a software system capable of maintaining and changing humidity and temperature based on user input. Results of different mea-surements done during the system's operation in a variable environment are evaluated to draw conclusions about the system's ability to maintain constant temperature and humidi-ty levels inside the glasshouse.
3

Sledování fenologických fází u bylinného a keřového patra ve smíšeném porostu po výchovném zásahu.

Pazderová, Jindra January 2010 (has links)
No description available.
4

Verifikace fenologického modelu pro lýkožrouta smrkového (Ips typographus) v České republice / Verification of fenological model of Ips typographus in the Czech Republic

Haramul, Michael January 2016 (has links)
During the months of April and June 2014 the spruce bark beetle (Ips typographus L.) capturing was conducted into the pheromone traps followed by the verification of phenological model PHENIPS altogether at two study locations in the Czech Republic: Horní Planá in the southern Bohemia and Lipník nad Bečvou in the Olomouc region. The trapping was performed weekly with the help of pheromone tabular traps Theysohn which were equipped by pheromone-type evaporators Pheroprax from Chemipan. The aim of the study was to verify the validity of phenological model PHENIPS for the spruce bark beetle in the Czech Republic and verify whether the model is applicable for the Czech Republic. At the end of the 2014 season with the help of phenological models PHENIPS and the number of trapped bark beetle specimen the term of swarming and the term of colonization of host trees were determined. The sister generation activity was probably recorded in the several traps.
5

Specifika sušení řeziva při nízkých teplotách

Jarkovský, Petr January 2016 (has links)
This thesis is addressing problems associated with the drying of oak timber in a condensing dryer. The fundamental of the work is verification of suitability of modi-fied drying durations and evaluation of the quality of the crustiness of the dried oak timber. The state of the crustiness is rated via two different methodologies, by the fork test according to ON 49 0651 and by the central cut test as prescribed in ČSN PEN V 14464. The results of both methods are compared. A part of research is also an eva-luation of the possibility of timber damage during the drying process. The work is sup-ported by experiments and practical measurements on test samples whose results are finally graded.
6

Sestavení recentní dubové standardní letokruhové chronologie pro severní Moravu

Bužek, Stanislav January 2017 (has links)
Theme and purpose of this diploma thesis was to compile a recent oak standard chronology for the region of Northern Moravia and to perform a dendroclimatological analysis. At three locations within the region of Northern Moravia, 195 samples from recent oaks have been collected using the Pressler increment borer. Tree-ring widths have been measured and processed in PAST 32 programme. From well-correlated tree-ring curves, a standard chronology has been successfully established with the range from 1895 to 2015. Removal of age-related trend from tree-ring curves and creation of residual standard index oak chronology has been performed in ARSTAN programme. Resulted residual chronology was used for modelling an impact of climatic variables on the radial increment in DendroClim programme, whilst also an analysis of significant negative years has been performed. Radial increment showed statistical and significant positive correlation with rainfalls occurred in last September and in March of this year. Thickness increment indicates statistically negative correlation with Palmer Drought Severity Index (PDSI) from April to August last year. The most significant negative years for radial increment, when more than 60% of all trees responded, were the following years: 1941, 1942, 1943, 1956, and 1998. These most significant negative years were caused by a lower rate of monthly rainfall accumulations and low temperatures during the growing season.
7

Vliv nadmořské výšky na sezónní růst stromů v ekotonu horní hranice lesa / Effect of altitude on intra-annual growth of trees in the treeline ecotone

Kašpar, Jakub January 2013 (has links)
RESUMÉ Tato práce se zabývá vlivem teplotních poměrů na intra-anuální růst smrku ztepitélo (Picea Abies (L.) Karsten) na alpínské hranici lesa v Krkonoších ve vegetačních sezónách 2011 a 2012. Monitoring probíhal na dvou lokalitách na jižním svahu Luční hory. První lokalita se nacházela v nadmořské výšce 1310 m n. m., přibližně na horní hranici zapojeného lesa, druhá pak v nadmořské výšce 1450 m n. m., ve stromových skupinkách nad horní hranicí lesa. Mezi lokalitami byl pozorován poměrně vysoký vertikální teplotní gradient jak u teplot vzduchu (1,2 - 1,7 řC), tak u teplot půdy v hloubce 10 cm (0,8 - 1,2 řC). Teplotní rozdíl mezi lokalitami se pak projevil v nižším pozorovaném přírůstu na výše položené lokalitě. Pozorované počátky kambiální aktivity se pohybovaly od 26. 4. do 21. 5. Začátek kambiální aktivity je ovlivněn množstvím sněhové pokrývky akumulované na lokalitách v průběhu zimy a s tím souvisejícím datem jejího odtátí, teplotami půdy a teplotami v přízemní vrstvě atmosféry. Délka kambiální aktivity se pohybovala mezi 55 - 77 dny, přičemž její délka byla nižší na výše položené lokalitě. Diferenciace buněk nastala bezprostředně po počátku kambiální aktivity a trvala od 111 do 132 dní. V porovnání sledovaných růstových sezón vyšla lépe růstová sezóna 2012, ve které byl průměrný přírůst stromů vyšší na...
8

Mikroprocesorem řízený regulátor teploty / Microcontroller based temperature controller

Perůtka, Martin January 2008 (has links)
The aim of the work was to design and carry out a microprocessor driven temperature controller which will be operated by PC or immediately by its own control panel. The controller should serve, for example, as a regulation of temperatures in rooms, in ovens where electrical energy is used for heat production. This controller is able to measure temperature through connected temperature sensors, which means a thermistor PT1000 and a thermocouple type K, and to regulate temperature by the help of a heating body connected to the power output part of the controller.In this piece of work there is an issue of temperature measuring by the help of thermocouples and thermistors analysed, there are also mentioned the means of controlling and switching of alternating electrical tension for power operating and analysis of an issue of device connection and communication by the help of RS232 interface and USB with PC. The work also deals with a design of PSD controller with its subsequent realisation. The controller is tested on a micro-condensational siccative oven developed for the UTB research in Zlín.
9

Inteligentní převodník Ni odporových senzorů s rozhraním Ethernet / Ni sensors to Ethernet convertor

Kubíček, Ondřej January 2010 (has links)
This work deals with hardware and software solution for the temperature converter of the standard rezistance temperature Ni sensors with the output through the Ethernet, driven by the Rabbit microcontroller. First part of this thesis deals with the theory of the temperature measurement. There are introduced basic principles of the temperature sensors. In the next part of the work are introduced communication standard and application protocol Modbus. The rest of the work deals with the hardware concept of the converter, the control program of the converter and the program developed for the PC.
10

Řízení vytápění rodinného domu / Control of house heating

Hnyk, Marek January 2016 (has links)
The aim of the final thesis is a proposal and implementation of a system which would enable a heating control on the basis of data gathered by monitoring of particular rooms inside a building. In particular, it is focused on water measurement within the heating system, TUV (non-potable hot water) and the temperature within the space of residential rooms. The system headquarters must enable an automated saving of the measured data. Selected temperature figures will be made accessible by a web interface and continuously saved on the web server.

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