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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

Využití NIR spektroskopie pro analýzy luštěnin

Dubanovská, Petra January 2010 (has links)
No description available.
2

Aplikace optimalizačních metod v hydrologickém modelování / Application of optimization methods in hydrological modeling

Jakubcová, Michala January 2015 (has links)
Finding the optimal state of reality is the main purpose of the optimization process. The best variant from many possibilities is selected, and the effectiveness of the given system increases. Optimization has been applied in many real life engineering problems as in hydrological modelling. Within the hydrological case studies, the optimization process serves to estimate the best set of model parameters, or to train model weights in artificial neural networks. Particle swarm optimization (PSO) is relatively recent optimization technique, which has only a few parameters to adjust, and is easy to implement to the selected problem. The original algorithm was modified by many authors. They focused on changing the initialization of particles in the swarm, updating the population topology, adding new parameters into the equation, or incorporating shuffling mechanism into the algorithm. The modifications of PSO algorithm improve the performance of the optimization, prevent the premature convergence, and decrease computation time. Therefore, the main aims of the presented doctoral thesis consist of proposal of a new PSO modification with its implementation in C++ programming language. More PSO variants were compared and analysed, and the best methods based on benchmark problems were applied in two hydrological case studies. The first case study focused on utilization of PSO algorithms in inverse problem related to estimation of parameters of rainfall-runoff model Bilan. In the second case study, combination of artificial neural networks with PSO methods was introduced for forecasting the Standardized precipitation evapotranspiration drought index. It was found out, that particle swarm optimization is a suitable tool for solving problems in hydrological modelling. The most effective PSO modifications are the one with adaptive version of parameter of inertia weight, which updates the velocity of particles during searching through the multidimensional space via feedback information. The shuffling mechanism and redistribution of particles into complexes, at which the PSO runs separately, also significantly improve the performance. The contribution of this doctoral thesis lies in creation of new PSO modification, which was tested on benchmark problems, and was successfully applied in two hydrological case studies. The results of this thesis also extended the utilization of PSO methods in real life engineering optimization problems. All analysed PSO algorithms are available for later use within other research projects.
3

Mobilní mapování pomocí GPS, zpracování dat a jejich vizualizace v aplikaci OziExplorer / Mobile mapping via GPS, the data processing and visual processing in the OziExplorer programme.

LORENCOVÁ, Petra January 2009 (has links)
The target of this thesis is data collection via pocket PC and GPS receiver, together with data processing and visualization in the OziExplorer programme. To the partial goals belongs the description of the specific parts of mobile mapping from the data collection to their visual processing in this programme. The mapping was done in the area of the national protected zone of the Boubín forest, located in the Bohemian Forest. Before the mapping, it was necessary to study the theory of the GPS system, pocket computer, OziExplorer programme and their practical usage including the operation of all the basic functions of the OziExplorer programme. The subsequent step was configuration of the measuring devices and preparation of the data for mapping. A very important part of the data preparation was a diligent calibration of scanned maps which was essential for reaching correct consecutive measurements. The data collection was done by a pocket computer ASUS A639 with an integrated GPS antenna, operation system Windows Mobile 5.0 CZ, and a PDA version of the programme OziExplorerCE. The data collected from the field work in the area of the national protected zone of the Boubín forest, where the measured route was the educational path called the Boubín forest, were processed in the PC programme OziExplorer. Some corrections were made and the final route was transformed to the 3D model via the programme OziExplorer3D. The result of the thesis is the description of the constituent stages of the mobile mapping from the preparation and the data collecting to the visual processing in the OziExplorer programme and 3D model of the relief of the Boubín forest.
4

Studium vlastností neutrin pomocí NOvA detektoru / Studium vlastností neutrin pomocí NOvA detektoru

Jelínková, Zuzana January 2017 (has links)
The NOνA experiment is a long-baseline neutrino oscillation experiment designed to measure electron neutrinos (νe) appearing in the NuMI beam, a muon neutrino (νµ) source at Fermilab. Its two detectors, Near and Far, are functionally identical active tracking calorimeters. This thesis is focused on the relative calibration of the Near Detector. The individual steps of the process, threshold, shadowing and attenuation calibration, are described. For the calibration, NOνA standardly uses cosmic muons. Alternative source, so called rock muons which are muons that originated from interactions of beam νµs with a rock surrounding the Near Detector, is introduced. The thesis guides through the development of selection criteria used to distinguish rock muon tracks from the data. Selected sample of rock muon tracks is used for the relative calibration and at each step the results are compared to the cosmic muons based calibration. The whole analysis is performed using simulated Monte Carlo data. 1
5

Analýza generátorů ekonomických scénářů (zejména úrokových měr) / Economic Scenario Generator Analysis (short rates)

Šára, Michal January 2012 (has links)
The thesis is concerned with a detailed examination of the most familiar short-rate models.Furthermore,it contains some author's own derivations of formulas for prices of interest rate derivatives and some relationships between certain discretizations of these short-rate models. These formulas are then used for calibration of ceratain chosen models to the actual market data.All the calculations are performed in R using author's own functions,which are along with the other more involved derivations placed in the appendix.
6

Kalibrace geometrie vln vytvořených na matrici(lisovnici) z plechu / Sizing of the waves geometrical parameters fabricated on the sheet metal die

Stupárek, Daniel January 2010 (has links)
This thesis approaches the problem of the return of the original geometric shape of the wave which is created on die panels. Die is used as a structural feature of the fiber-cement roofing material in its shipment in the production line. Based on the study of the theory of cold formed sheet metal determine the actual status in the plant. The method of calibration was designed from the collected informations about the original manufacturer of sheet metal panels. Under this proposal and calculation of the required forming power for the recalibration wave in the factory device for the die calibration was designed and constructed. Equipment calibration was performed on two types of corrugated panels and the result fulfilled the theoretical assumptions. In conclusion is processed technological-economic evaluation and the accompanying drawings.
7

Studium plazmatu v zařízeních typu tokamak spektroskopickými metodami / Study of plasma in tokamak-type devices with spectroscopic methods

Naydenkova, Diana January 2017 (has links)
In Tokamak department of Institute of Plasma Physics, radiation of high-temperature plasma is investigated using spectroscopic methods in visible, ultraviolet and infrared regions. The radiation gives information regarding tokamak plasma parameters and their changes, which is necessary for future realization of fusion reactor. In the frame of this doctoral thesis the development of spectroscopic diagnostics for observing of plasma radiation and its temporal evolution in COMPASS tokamak was performed. The absolute calibration of developed systems in order to recalculate measured signal to units of radiation was done. The sources of imprecisions of absolute measurements in tokamak conditions are properly discussed in the first part of the dissertation. Plasma radiation in the range 257-1083 nm was measured and interpreted using NIST database and FLYCHK code. Ion density for the most significant impurities was estimated. IDL code for effective ion charge estimation as a ratio of real and hydrogen plasma Bremsstrahlung radiation near 523 nm was developed. Profiles of electron density and temperature measured by Thomson scattering system were used for hydrogen plasma Bremsstrahlung radiation calculations. The example of applying of spectroscopic data for studying of COMPASS plasma heating using neutral beam...
8

Využití NIR spektroskopie ke kontrole kvality potravinářských výrobků

Dvořák, Lukáš January 2016 (has links)
The aim of this thesis was to verify and evaluate the possibility of using NIR spectroscopy usage in food products quality control. The quantitative calibrations were developed to determinate of chemical parameters of sheep, goat and cow milk, honey, coffee and another food and raw materials. Food samples were evaluated by the FT-NIR Antaris spectroscope in a spectral resolution of 10 000 to 4 000 cm-1 with the possibilities of samples measurement in reflectance, transmitance or interactance mode. Calibration models were created by using a Partial Least Square algorithm (PLS) and also the cross-validation was used for the verification of the quality prediction of calibrations. Very good calibration were developed in most cases, and though some were less accurate calibrations are applicable to at least approximate determination of values. The ability of FT-NIR spectroscopy to classify sensed spectrum into predefined classes and thereby determine the differences between groups of samples was verified with a qualitative evaluation of products using with discriminant analysis. A suggestibility verification of the device was realized with cow's milk, which was measured at various temperatures. It was confirmed that the NIR spectroscopy is useful for the chemical composition and food quality evaluation.
9

Hodnocení změn při dozrávání a skladování ovoce s využitím metod NIR spektroskopie

Šnurkovič, Petr January 2016 (has links)
The dissertation thesis is focused on investigation of possibilities of usage NIR spectroscopy for nutritional composition of fruit and vegetables evaluation. The basic nutritional components of fruit and vegetables, methods of apples, peaches and tomatoes storage are characterized in the literary section. The history of infrared spectroscopy, present, principles and types of NIR spectroscopy analyses are described in detail. The possibilities of usage of NIR spectroscopy in food industry aimed on fruit and vegetables quality evaluation are also described in the literary section. Changes of fruit and vegetables nutritional composition during ripening are evaluated in the experimental part. Evaluated fruit and vegetables were apples (variety Rubinola), tomatoes (variety Dagmar) and peaches (variety Redhaven). Changes in the total polyphenols content, titratable acids, soluble dry matter, malic acid, ascorbic acid, citric acid, peel firmness and apple flesh firmness were evaluated. Calibration models were prepared from the gained data using the NIR spectroscopy method. The changes of stored fruits nutritional composition were evaluated using the created calibration models. Soluble dry matter, titratable acids, ascorbic acid and flesh firmness of different apple, peach and tomato varieties can be determined fast and exactly according to the data. The accuracy of models for total polyphenols and peel firmness is significantly influenced by the number of calibration standards. The accuracy of models for malic and citric acids is influenced by the concentration of these components in fruits.
10

Měření a kubírování dříví harvestory v porovnání s manuálními postupy

Bauer, Jan January 2018 (has links)
The diploma thesis is focused on comparison between timber measurement and log volume determination by harvesters and manual methods. The issues of measurement by harvesters is calibration of measuring system and principle of measurement, searching of source of mistakes and influeancing. In field conditions on property of Lesní správa Bruntál, LČR s.p. was performed an analysis of measurement with a difference between harvester and manual measuring from 1,14 % to 3,20 %. The measurement was realized in a random bark beetle extraction. Harvesting was performed by harvestor Timberjack 1270 D equipped with TimbermaticTM 300 system.

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