• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 45
  • 3
  • Tagged with
  • 48
  • 24
  • 20
  • 17
  • 17
  • 14
  • 11
  • 9
  • 9
  • 7
  • 6
  • 6
  • 5
  • 5
  • 5
  • 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

Zjišťování koeficientů difúze vlhkosti u dřeva a materiálů na bázi dřeva pro potřebu optimalizace rozměrů stavebních prvků

Čermák, Petr January 2011 (has links)
No description available.
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

Tok vlhkosti a atmosférické srážky v Evropě / Moisture fluxes and precipitation in Europe

Lemarie, Petr January 2012 (has links)
The present thesis deals with the influnence of moisture flux and variables, it is derived from, on rainfall in Europe. Sources of this thesis are the NCAR/NCEP and the ERA-40 reanalysis and the GPCC and the ECA&D rainfall databases. A western moisture flux prevails on studied 850 hPa isobaric level, it reaches the highest intensities over the Atlantic around 55th parallel of latitude. There is the highest correlation between moisture flux magnitude and monthly rainfall in winter on the western coast of Europe and it decreases in summer and eastwards. The correlation is very weak or none in some parts of Europe, especially in the eastern Mediterranean. Extremely wet months are related with different intensive moisture flux directions in different parts of Europe, for example there is the highest correlation of monthly rainfall with the northern moisture flux in the Czech Republic. Several selected heavy precipitation episodes in Europe are presented in this thesis - during them the moisture flux anomaly is observed, but it differs in orientation and intensity. A high wind speed causes this anomaly more frequently than a humidity. This does not apply to every event, furher research is needed to draw general patterns of moisture flux during high precipitation events.
4

Datalogger pro stavební konstrukce / Datalogger or building constructions

Štábl, Martin January 2017 (has links)
This work deal with developing dedicated autonomous device for data collection. The work describes the approaches how to design that. Solve choosing of the sensor taking into his properties for this device. And regard on the comparison with similar devices on market according behavior and function. General concept of the suggested datalogger. The thesis contains hardware and software equipment of this device.
5

Hygrotermálna odozva stavebných konštrukcií / Hygrothermal response of building components

Slávik, Richard January 2019 (has links)
This dissertation thesis is focused on the study of simultaneous transport of heat and moisture in building components. First, the introduction briefly summarises current international state of the art in assessment and evaluation of building components focused on moisture. Besides description of methodological approaches and analysis of differences between them, the approaches are modelled using examples which help to identify their properties and explain the application framework of the methods. These examples do not only illustrate the procedures; they also indicate their limits and identify the pitfalls of models’ application in comparison with each other. Next, the thesis includes basic introduction to material parameters necessary in numerical modelling. Moreover, solutions to questions from the assignment are discussed from the point of view of the theory of heat and moisture transport. To fulfil the thesis’ objectives, theoretical analysis and calculations were implemented. Calculations were carried out not only by well-known methods, but also using an own-developed complex algorithm which implements simultaneous heat and moisture transport modelling based on finite element methods and which allows to implement nonlinear behaviour of material properties. Furthermore, the thesis contains description of and results from two experiments. A brief description of an electronic device developed and used for the experiments is included. Experimental results are confronted with both simplified and advanced theoretical models. At last the thesis concludes with discussion of acquired findings, brief summary of potential contribution of this work to the field of building science and engineering practice, and indication of the directions for further development.
6

Analýza metod měření vlhkosti ve stavebních materiálech / Analysis of methods used for measurement of moisture in building materials

Hrabálková, Eliška January 2021 (has links)
The diploma thesis is focused on the issue of measuring the moisture content in building materials using indirect methods that allow its long-term measurement. The theoretical part of the thesis provides an overview of the forms of moisture in porous building materials and provide an overview of the principles of measuring moisture content. In the experimental part of the thesis, the aim is to verify the available methods for long-term monitoring of moisture in building materials built into building structures. Proven methods of measuring humidity include resistance, capacitive and microwave methods and their comparison with the results of gravimetric measurements. At the end of the work is an evaluation of knowledge and recommendations for further research in this area.
7

Hodnocení metod pro stanovení vlhkosti ve stavebních konstrukcích / Evaluation of methods for determining an air humidity in building constructions

Nogová, Tereza January 2015 (has links)
This thesis compares the methods for the determination of air and moisture condensation in the construction. There are descriptions of the various methods and formulas for measuring humidity and methods for the calculation of condensation in building structures. The practical part describes the development of a method for verifying the condensation of moisture in construction. Parts of this work are the materials and methods for the development of the humidity sensor. There were used two methods – capacitive and resistive for measuring moisture condensation. In the conclusion is the evaluation of the humidity sensor and compares the results of individual measurements.
8

Sdružené transportní procesy / Coupled transport processes

Jeřábek, Jakub January 2015 (has links)
The objective of this thesis was to implement a new module to the DRUtES model code, which allows to calculate coupled transport of moisture, temperature and miscible substance in a variably saturated porous media. The main part of the practical phase of the thesis was to implement appropriate constitutive relationships describing a coupled transport to the Galerkin finite elements scheme previously implemented in the DRUtES model. Besides this, a corresponding configuration files were made to assign parameters of the model into program data structures as well as a little bit of other programming work elsewhere in the code. Numerical solution of each transport equation was compared with its analytical solution. 1D moisture transport with the Philips semi-analytic solution of diffusive form of Richards equation. 2D temperature and miscible substance transport with an analytical solution of advection-dispersion equation. This comparisons suggested that the implementation was correct. The coupling of these processes was compared with a reference numerical solution. In this case was the fitness of results assessed in more qualitative manner with a literature. Before use of this coupled model to solve a real world problem, I would recommend to make a similar assessment with the real data.
9

Marketingová strategie značky Ceresit / The marketing strategy of the brand Ceresit

Wachalová, Veronika January 2014 (has links)
The aim of the dissertation is to evaluate marketing strategy of the brand Ceresit and its product line STOP Humidity (STOP Vlhkosti). The theoretical part defines fundamental concepts such as marketing and strategy, furthermore, it describes the steps of strategic marketing process. Also, the dissertation introduces Henkel, the brand Ceresit STOP Humidity and its product portfolio. The practical part involves internal and external analysis, however, it primarily focuses on the elements of marketing mix of the brand Ceresit STOP Humidity. As for methodology, particularly field research and content analysis are used throughout the study. Finally, SWOT analysis is employed to summarize key outcomes followed by author's recommendations resulting from the research.
10

Výměna tepla v trubkových výměnících / Heat transfer in the tubular exchangers

Horvát, Petr January 2019 (has links)
Shell and tube heat exchangers and their use in cooling processes are the major topic of this thesis. The theoretical part of the thesis starts with the mechanisms of heat transfer and then deals with shell and tube heat exchangers. Their position, design specifications and equations for calculations are given. In the experimental part, the heat transfer on semi-operating shell and tube heat exchangers with baffles and glass or silicon carbide heat exchange surface is examined by cooling the humid air by 50% propylene glycol in tubes. For four or five coolant flows and three airflows, input and output flow temperatures including relative air humidity were measured. Differences in exchanged heat between the exchangers were negligible due to the low local air heat transfer coefficient, although silicon carbide has two orders of magnitude better thermal conductivity than glass. Much higher efficiency was performed by the carbide heat exchanger because the difference between air outlet temperature and liquid inlet temperature was one and half times higher for the glass heat exchanger. That was reflected in a decrease in mean temperature difference, which resulted in a 16 % higher experimental heat transfer coefficient compared with the glass surface. The theoretical model using the j factor, the correction factors for the baffles, and the correction for air humidity condensation have proven to be appropriate. For the glass surface, for the highest air flow rates the model gives an appropriate heat-transfer coefficient; at lower flow rates it gives slightly higher values. For the silicon carbide surface, it gives a lower heat-transfer coefficient because the model failed to consider a lower mean temperature difference. The results also evaluate the heat loss through the shell and the heat exchanged in addition by air humidity condensation.

Page generated in 0.0271 seconds