National Repository of Grey Literature 825 records found  1 - 10nextend  jump to record: Search took 0.00 seconds. 
Effect of global climate change on areal and phenology shifts of dragoflies species
Perthen, Ervín ; Černý, Martin (advisor) ; Bílková, Eva (referee)
Climate change in recent decades affects the distribution and phenology of dragonflies. The main factor causing these changes is the increase in the average global temperature, but other factors, such as loss of habitats or changes in precipitation regime, also play a role. As a result of climate change, phenological processes are accelerating. We can therefore observe a faster egg development rates, an earlier emergence of adults, a longer flight period and also a shift in voltinism towards a greater number of generations per year. Good dispersal abilities allow dragonflies to respond to changing environmental conditions also by shifting their distribution. The ranges of most species are currently expanding towards the poles. Generalists and species capable of using temporary waters expand their ranges the most, while specialized species with a narrow niche are the most threatened by climate change. Shifts are also visible in the altitudinal distribution, increasing temperatures allow warm- adapted species to expand their ranges to higher altitudes. Keywords: climate change, dragonflies, distribution, phenology, temperature, altitudinal shift
Arctic amplification: causes, manifestations, impacts
Houser, Mikoláš ; Huth, Radan (advisor) ; Krauskopf, Tomáš (referee)
The Arctic amplification is a byproduct of the climate change, manifested by faster warming in the Arctic region compared to other parts of the planet. This paper summarises the basic understanding of the mechanisms underlying this phenomenon (mainly snow-ice albedo and temperature feedback) and the potential impacts of Arctic amplification for atmospheric circulation at mid-latitudes. The research is completed by a correlation analysis describing the relationship between Arctic amplification and the North Atlantic Oscillation. Based on the literature it is suggested that Arctic amplification may influence various factors of the mid-latitude atmospheric circulation (e.g., phases of the North Atlantic Oscillation, jet stream, circumpolar vortex), but natural variability of the climate makes it difficult to unravel this relationship. Recent climate model outputs seems more likely to show a smaller influence of Arctic amplification compared to the internal variability of the climate system. This is demonstrated by the results of the correlation analysis, which show very little statistical connection of the observed variables and large statistical uncertainty in the results.
Simplified design of heat exchangers using MS Excel
Konečný, Ondřej ; Jegla, Zdeněk (referee) ; Kilkovský, Bohuslav (advisor)
This bachelor thesis deals in the first part with the research, where the types of heat exchangers are briefly described. The next part contains the basic equations for the calculation of heat exchangers as well as different approaches to the calculation of these devices. The practical part of this thesis focused on the development of the calculation tool, the corresponding manual and the functionality checking with examples.
Design and developement of autonomous system for monitoring critical paramaters in food industry
Chovan, Hynek ; Formánek, Martin (referee) ; Krejčí, Petr (advisor)
his work focuses on automating the monitoring of temperature and other operational parameters in gastronomic establishments. The designed device allows real-time monitoring of temperature, humidity, and other parameters with remote access capability. It utilizes the ESP32 microcontroller, SHT40 and HX711 sensors, and TP4056 charging circuit with DW01A protection circuit. Data is transmitted to a Gateway device, which displays it through a web interface. Testing demonstrated sufficient communication range and long battery life. The device meets requirements for compactness, reliability, and efficiency. This project represents progress in IoT applications for ensuring food safety and efficiency in handling food in gastronomic establishments.
Possibilities of limiting unwanted phenomena during chip finishing machining
Handl, Jiří ; Osička, Karel (referee) ; Kalivoda, Milan (advisor)
The diploma thesis focuses on the possibilities of limiting undesirable phenomena during finishing chip machining. In the theoretical part, selected negative phenomena arising during turning are described and the possibilities of their limitation are investigated. In the experimental part, an analysis of the influence of cutting conditions from the recommended range of the cutting tool using the turning method is carried out. Specifically, the dependence of the cutting speed and feed rate on the size of the cutting force, temperature and resulting surface quality for two different materials is monitored. The obtained results serve to understand the issue and optimize the production process.
Optimising the working environment through Internet of Things technologies
Šebo, Martin ; Matej,, Havlas (referee) ; Sedlák, Petr (advisor)
This master’s thesis is focused on the analysis of the working environment of Stellnaris s.r.o. through the Internet of Things devices in terms of temperature, humidity, air quality and noise. The aim of the thesis is to analyze and propose the optimization of the monitored premises so that the network elements (especially the active ones) run as efficiently as possible, their long lifetime is achieved and also so that the comfort of the persons present in the premises is achieved in case of work performance. The subject of this work is not the monitoring of the entire company premises, but only selected areas, which are specified in more detail in the chapter Analysis of the current state.
Short time overload of cables in UPS applications
Toman, Dominik ; Pravda, Luděk (referee) ; Šimek, David (advisor)
This bachelor’s thesis is about dimensioning power cables in electrical instalation which is described in the third chapter. If is used cable with small cross-section, relatively high direct current which is flowing through these cables could cause too high warming. Function of this electrical instalation and comparison of batteries which should be possibly used, are described in the first chapter. Second chapter shows risk of using cable with small cross-section, which could be overheated due to current overloading. Cables are designing in accordance with IEC 60364-5-52, IEC 60364-5-54 and duty cycle. Cross section values calculated according to all methods are very different. Cross section calculated in accordance to IEC 60364-5-54 and duty cycle are smaller then cross-section values calculated in accordance to IEC 60364-5-52. Cable with smaller cross section is cheaper, but it is possible that smaller cross section could cause bigger warming. This thesis also contains thermal model and warming measurement, both methods are for verification that cable with smaller cross-section could be used. Third chapter also contains calculations of voltage drops on all calculated cross-sections. Values from thermal model and warming measurement are different but they are both confirming that the cable with smaller cross section could be used.
Buckling analysis of the load-bearing system
Majer, Tomáš ; Löffelmann, František (referee) ; Šplíchal, Jan (advisor)
The research part of the work summarizes the knowledge in the field of calculation of buckling stability and methods of heat transfer. The next part deals with the calculation of the buckling stability of two types of samples using an analytical approach, finite element method, and verified using experimental measurements. Finally, the work deals with CFD calculation for determining the temperature field on the examined samples, which is used to calculate the buckling stability with temperature influence.
Zlín FCK Technology
Honzák, Jiří ; Kudla, David (referee) ; Štěpán, Marek (advisor)
Temperature is an integral part of every space, yet in today's world of technological solutions, few people realize how important role it plays in various aspects of architecture and the social ties of the people within it. This master thesis deals with the design of a universal parametric system of community porch houses with an emphasis on the use of the spatial character of temperature in the interior, and subsequently applies this system to a specific building design in Malenovice near Zlín.
Monitoring the living environment in the house
Dlugoš, Daniel ; Ježek, Michal (referee) ; Staněk, Kamil (advisor)
This work, tries to create a small, rechargeable and portable device that senses temperature, humidity, barometric pressure, dust particles, carbon dioxide and VOC concentration. The air quality monitor can reliably measure the physical quantities encountered in every indoor environment, evaluate them and display them to the user. The sensors, data storage module and OLED display are housed on a custom-made PCB board.

National Repository of Grey Literature : 825 records found   1 - 10nextend  jump to record:
Interested in being notified about new results for this query?
Subscribe to the RSS feed.