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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.
11

Dynamika tripletních stavů pigmentů ve fotosyntetických světlosběrných komplexech / Dynamika tripletních stavů pigmentů ve fotosyntetických světlosběrných komplexech

Kvíčalová, Zuzana January 2011 (has links)
Chlorophyll molecules in their triplet excited state can react with the ground state oxygen, producing oxygen in a singlet excited state, which is very reactive and thus very harmful to the light-harvesting complex. Photosynthetic organisms employ carotenoids to prevent the damage by quenching both excited (singlet) states of oxygen and excited triplet states of chlorophyll. In this work, we use ns transient absorption spectroscopy and global analysis to study the dynamics of carotenoid and chlorophyll triplet states in two light-harvesting complexes of Amphidinium carterae, the Peridinin-Chlorophyll a-Protein complex (PCP) and the main light-harvesting complex (LHCP). It appears that at room temperature all triplets are transferred from chlorophylls to carotenoids within ~ 5 ns, providing a very efficient protection against formation of singlet oxygen. One carotenoid triplet with a lifetime of ~ 10.2 µs participating in the chlorophyll triplet quenching was observed in the PCP sample, while results from LHCP suggest that two carotenoid triplets with a similar lifetime of ~ 2.5 µs contribute to quenching of chlorophyll triplet states. The two carotenoid triplets are attributed to peridinin placed in a polar environment and peridinin placed in a non-polar environment in the LHCP complex.
12

Analýza spolehlivosti v oblasti IT / IT systems reliability analysis

NOVÁK, Rudolf January 2009 (has links)
The main goal of this diploma thesis "IT systems reliability analysis" is to analyse and suggest the best PC component seller according to criterion of minimum costs for guarantee services. Theoretical part deals with general importance of technical systems reliability and brings methodological basis for reliability analysis and describes methods and ways how to increase reliability in practise. Following part is focused on identification computer most critical component through Failure Tree Analysis method and modelling its failure-free time by using Weibull analysis. On the base of maintenance costs analysis was chosen the most appropriate distributor.
13

Systémová dynamika: případ výkonnosti projektových týmů / System dynamics: case of project team performance

Madry, Martin January 2014 (has links)
This thesis deals with modelling of project teams and their behavior using the principles of system dynamics. Main goal of this thesis is to create a model using system dynamics, which will allow to simulate how projects are finished. Results from the model are going to be used to define the best possible strategy to finish a project in required time. Theoretical part of this work is composed of presentation of project management and further the thesis extensively describes system dynamics, principles of system dynamics, used diagrams and possible ways of application of system dynamics in the real world. Furthermore are described the principles and advantages of using models and specifically system dynamics models. In the practical part of this thesis is presented the created model, which allows for simulating of project team behavior based on the input from the user of the model. Model serves the purpose of finding the best possible strategy to finish the product successfully.
14

Hodnocení možnosti vzniku vnější sufoze/ztekucení a řešení metodou dílčích součinitelů. / EVALUATION OF THE POSSIBILITY OF THE ORIGIN OF THE EXTERNAL SUFFOSION / HEAVE AND SOLUTION USING THE LIMIT STATE METOD

Hala, Mario Unknown Date (has links)
In the case of soil structures and/or subsoil of the water structures, filtration deformation can occur due to the effects of water seepage. One of the possible phenomena that can occur in water structures due to filtration deformation is external suffusion / heave, which ocure on the air side of the structure in the case of ascending external seepage, where soil particles are gradually subject to ascending seepage forces. The possibility of heave can be assessed using the method of partial factors, for which individual partial factors are needed, which are not specified in more detail in the literature. The aim of this work is to determine the partial reliability factor for failure due to heave based on the evaluation of laboratory experiments on uniform grain materials with non-uniformity number CU
15

Zeemanův jev v polovodičových kvantových strukturách / Zeemanův jev v polovodičových kvantových strukturách

Stráský, Josef January 2011 (has links)
This theoretical thesis presents detailed study of negatively charged excitons - trions - confined in single quantum well in presence of perpendicular magnetic field. Complex valence band of GaAs/GaAlAs compound is described within Luttinger Hamiltonian framework. Singlet and triplet states of negative trion are introduced. Advanced theoretical analysis of Zeeman effect for different states of trion is performed. Landau gauge of magnetic field and unusual wavefunctions basis is chosen and its accuracy is tested. Evolution of ground state energy and photoluminescence spectra with magnetic field is evaluated for different values of Landé g-factors. Probability of occurrence of electrons with respect to the hole position and their spatial correlation function are investigated.
16

Modely pro podporu rozhodování managementu destinace cestovního ruchu / Models Supporting Decision Making of a Tourism Destination Management

STUDENÝ, Zdeněk January 2019 (has links)
This diploma thesis focuses on the application of system thinking and its methods to the issues of decision making within destination management and its organizations. The main aim of the thesis was to create a model to support decision making of destination management organization and to plan sustainable and responsible tourism development in the destination. A partial aim was to create a simplified model in which a simulation of the given system was performed. This aim has been applied to the destination of Cesky Krumlov. The contribution of the work is to find optimal decisions, policies and individual processes in order to assess the subsequent impacts and manage the development of tourism destination towards sustainability.
17

Semiklasická energie eliptické Nambuovy-Gotovy struny / Semi-classical energy of elliptic Nambu-Goto string

Kozoň, Marek January 2018 (has links)
Po zhrnutí potrebných teoretických základov a predošlého výskumu v ob- lasti, prezentujeme semi-klasickú kvantovaciu schému pre uzavretú Nambuovu- Gotovu strunu. Týmto zovšeobecňujeme predošlú prácu, ktorá bola vykonaná pre otvorenú strunu a uzavretú strunu kruhového tvaru. Pomocou metód kvan- tovej teórie po©a v zakrivených priestoročasoch počítame strednú hodnotu vo©- ného Hamiltoniánu struny rotujúcej v dvoch na seba kolmých priestorových rovinách v priestoročase všeobecnej dimenzie. Táto hodnota je priamo úmerná kvantovej korekcii k celkovej energii struny, ktorá má formu tzv. Reggeovho interceptu. Výslednú hodnotu Reggeovho interceptu porovnávame s predošlým výskumom. Taktiež uvádzame porovnanie získaného spektra fyzikálnych stavov struny kvantovanej našou metódou so spektrom odvodeným pomocou kovariant- ného kvantovania. 1
18

Studium interakcí iontů s molekulárním vodíkem v závislosti na jaderném spinu při teplotách relevantních pro astrochemii / Study of state selected interactions of ions with molecular hydrogen at temperatures relevant to astrochemistry

Zymak, Illia January 2013 (has links)
In this work are presented results of the experimental study of state selected reactions of H+ and N+(3PJa) ions with molecular hydrogen H2(J = 0, 1) at temperatures in the range 10 - 100 K using 22-pole rf ion trap apparatus. These reactions are important for the formation of interstellar trihydrogen cations and ammonia. To determine the temperature of ions, calibration measurements of the Doppler broadening of spectral lines using N2+ + Ar  Ar+ + N2 laser induced reaction and rate of the ternary association He+ + 2He  He2+ + He were performed. Both ternary and radiative channels of the H+ + H2(J) association reaction were observed at hydrogen number densities in the range 1012 - 1014 cm-3 and 1011 - 1012 cm-3 respectively. Obtained temperature dependences at 11 - 33 K demonstrate substantial role of the H2 rotational energy, results cannot be explained with the existed theories of the stabilization of collisional complexes. Measurements of the rate coefficient of N+(3PJa) + H2(J) reaction at different ortho fractions of H2 show dependence on internal energy of both reactants. State specific rate coefficients of the reaction of nitrogen and hydrogen ions were derived. The adiabatic model and collisional relaxations of N+(3PJa) fine structure levels were considered. Powered by TCPDF (www.tcpdf.org)
19

Simulační modelování elektrických pohonů pro vybrané kritické aplikace / Simulation modeling of electric actuators for selected critical application

Toman, Jiří Unknown Date (has links)
The dissertation thesis with the topic „Simulation Modelling of Electrical Drives for Selected Critical Applications“ focuses on the area of given applications in civil aviation. The selected application that the thesis deals with is an electrically driven and electronically controlled fuel pump supplying fuel to an aviation motor of the APU type. The thesis gives a comprehensive description of the design cycle of the unit and demonstrates implementing all the required critical functions. In the course of the design of the unit modern techniques in mathematical modelling, simulation, verification, monitoring and prediction of the operation status of airborne equipment were uses to the utmost extent. The purpose of these was to show the suitability of their application with regard to decreasing design time and cost, increasing lifetime and servicing intervals, as well as increasing user comfort and decreasing price. At the same time the required reliability was to be kept. The thesis also aims to prove and verify the suitability of using electronically commutated dc motors in critical applications in civil aviation. To reach this goal, it is necessary to design a robust drive control which would meet the given reliability requirements.
20

Aplikace systémové dynamiky v managementu zdravotnického zařízení / Application of system dynamics in the management of medical facilities

Kastner, Pavel January 2012 (has links)
At the present time, characterised by increasing complexity of not just socio-economics systems, decision-making in positions of executive management is becoming increasingly difficult. Although more and more attention is dedicated to use of information and communication technologies in corporate sector and organizations collect unprecedented amount of very detailed data from all areas, their real nature is often not considered. Data, information and knowledge, through which we can achieve real understanding of causes of the observed systems behaviour, are necessary basis for ability for prediction of tomorrow's effects of today's decisions. This thesis aims to highlight the essence of data, information and knowledge in organization and the necessity of systemic perception for creating efficient and effective decisions. The second part of this thesis presents design of system-dynamic model (including user interface), which explains the mechanisms of health care volume accounting in medical facilities with more departments. The model should facilitate understanding of functioning of hospitals by the public, and respect of general nature of medical facilities functioning to create a base for robust model-oriented decision support system for the management.

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