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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.
111

Diferenciální elektromagnetická analýza / Differential electromagnetic analysis

Novotný, Bohumil January 2013 (has links)
This diploma thesis studies the theory side channels, simple and differential analysis, and types of attacks on the side channel, which may be run against the cryptographic system. The thesis explains the principles of side channel attack on a possible defense against them. The second part of the thesis describes experimental work created, its individual components and their functions. The findings builds custom solutions attack the electromagnetic side channel using electromagnetic probes and the workplace equipment developed for this task. The final part of the thesis is devoted to the description of the implemented algorithm, a description of measurement, measurement results and possible modifications of algorithms implemented in the microcontroller for full automation of the attack on the device, against which the attack was conducted.
112

Měření permitivity materiálů koaxiální sondou / Permittivity measurement of materials by coax probe

Ryba, Ivan January 2015 (has links)
This thesis describes possibilities of measuring permittivity of various materials, especially with coaxial probe method. It describes character of measuring method, hardware requirements and how to calculate values from the measured. Objective of this thesis is to design measuring station for measuring permittivity of materials with coaxial probe including calibration set. Code in Matlab is also programmed and whole station is tested with known samples to discuss measurement accuracy.
113

Aplikace měřicích sond v procesu obrábění / Application of a measuring probes in milling proces

Kulhánek, Jaroslav January 2009 (has links)
The object of this work is to apply the measuring probe in the process of the machining and explore the use of the measuring probes. For the practical of the measurement was use measuring probes, the program supplied with the measuring probes, machining centers and the resulting data were evaluated on a PC. Finally, work is to evaluate the measurements and describe the appropriateness of the application.
114

Měření na turbínové mříži / Measurements on Turbine Cascade

Vondra, Marek January 2015 (has links)
The Aim of this Diploma thesis is the measurement on turbine cascade. The first part is focused on measurement of the flow characteristics of the turbine cascade using a three–hole pressure probe. The second part includes the blade profile pressure measurement. Both measurements are performed both experimentally and by computer simulation in Ansys and the results are compared. Part of the work is also file containining the computer simulation, which was carried out in CFX program.
115

Měření fyzikálních veličin na rotujících částech / Physical Quantities Measurement of the Rotating Parts

Štorek, Pavel January 2009 (has links)
This work is dedicated to small distance contact-less measurement. Especially the surface detection of the commutator or collector of the electrical machines was described. The probes utilising the induction principle of the distance measurement have been developed. The part of the work described the history of the induction distances sensing in FEEC BUT and the using of the induction principle in the industry small distances sensing nowadays. The paper concretely determines the possibilities of the small distances measurement using mentioned probes. The sensitivity for different materials was investigated and the error of the measurement for different measuring object was investigated, too. The effects, that could affected the measurement error, were described in the work. The contribution of the each effect for the total measuring error was specified. Next part is including the description of the measuring workstation and of the hardware and software. At the end the verification of the measuring principle and measuring workstation is presented. The verification has been made on three different commutator types. The verification results are in the conclusion.
116

Flexibilní měření toků na síti / Flexible Network Flow Measurement

Varga, Ladislav January 2010 (has links)
This thesis deals with designing the probe used for measuring network flows. It contains theoretical analysis of network measurment topic, description of algorithms and principles used for network flow measurement. Emphasis on the probe architecture lies on efficient indexing algorithm and flow record flexibility, such that user is able to define format of flow record.
117

Diagnostika plazmatu využívající neutrální lithiový svazek na tokamaku COMPASS / Plasma diagnostics using neutral lithium beam on the COMPASS tokamak

Háček, Pavel January 2018 (has links)
The doctoral thesis presents the diagnostic neutral lithium beam on the COMPASS tokamak in Prague. The technical part describes the system for injection of accelerated lithium beam into the COMPASS tokamak and the respective detection systems for beam emission spectroscopy. The physical part describes the analysis of measured spectroscopic data, with particular emphasis on density fluctuations in the edge plasma. Detailed analysis of turbulent structures outside of the confined plasma region is presented, as well as investigations of the ELM instabilities during high confinement mode plasma operation. The thesis also presents the development and proof-of-concept measurements of a new and unique diagnostic method - atomic beam probe. The method uses detection of the ionized part of the beam for current density profile measurements in the plasma edge.
118

Za devatero horami - představy o neznámém / Once upon a time - Images of the unknown

Samková, Barbora January 2019 (has links)
Master's thesis applies theme unknown landscape. The theoretical part is devoted to concept landscape, which is viewed from different perspectives in the work; from defining the landscape as a generic term through subjective perception to the possibility of its use as an imaginative space. The research part describes field research, which deals with issues of different interpretations of landscape perception by children of younger school age. Within the framework of the didactic part are presented the tasks in which the theme of an unknown country is reflected in various forms and are designed for art lessons in elementary schools. Finally practic part of my work comes out from theme unknown countryside and I try to express my own artistic expression. KEYWORDS Imagination, spatial concepts, space, unknown landscape, field research, children of younger school age, creative activity
119

Architektura programového vybavení monitorovací sondy na bázi toků / Software Architecture for Flow Based Monitoring Probe

Špringl, Petr January 2009 (has links)
This thesis deals with design and implementation of software architecture for Flexible FlowMon probe, accessories for monitoring high speed computer networks based on IP flows. The probe has been developed in project named Liberouter. There is described flow based monitoring and export formats NetFlow version 5, NetFlow version 9 and IPIFX, which are very widely used. The thesis contains description of hardware part of Flexible FlowMon probe including its requirements for software, which are the base of the whole software architecture. There is detailed description of that part of software architecture which was implemented during the work on this thesis.
120

[pt] ANÁLISE DE INCERTEZAS E REDUÇÃO DE CENÁRIOS EM ALOCAÇÃO DE RECURSOS DE TAREFAS DE SONDAS MARÍTIMAS: UMA ABORDAGEM DE MACHINE LEARNING / [en] UNCERTAINTY AND SCENARIO REDUCTION IN MATERIAL RESOURCES ALLOCATION OF OFFSHORE RIGS: A MACHINE LEARNING APPROACH

RACHEL MARTINS VENTRIGLIA 18 April 2024 (has links)
[pt] O planejamento de recursos materiais é uma parte importante do gerenciamento da cadeia de suprimentos. As tarefas na cadeia de suprimentos precisam de materiais e recursos para serem executadas e, portanto, alocar os recursos corretamente é uma parte importante do planejamento de tarefas. Especificamente, as tarefas de construção de poços submarinos requerem a utilização de recursos, como sondas, e o planejamento do cronograma dessas operações envolve o dimensionamento de diversos materiais e serviços necessários para sua execução. Este estudo é motivado pelo planejamento de programação real de uma grande empresa de Óleo e Gás que estima estocasticamente a demanda por materiais e serviços devido às incertezas associadas às tarefas em suas datas de início e durações. O cálculo da demanda varia de acordo com o cronograma atual que a empresa possui e a um conjunto de regras que indicam condições de alocação, parâmetros logísticos, condições de desembarque e dependências para alocar as ferramentas e serviços necessários para cada tarefa e estimar sua quantidade e quantos dias em que serão usados. Este conjunto de ferramentas e regras pode mudar dependendo do usuário e de seu conhecimento operacional. Além disso, a empresa utiliza um grande número de cenários, o que resulta em tempos computacionais extremamente altos e impacta a tomada de decisões operacionais. Nesse contexto, a redução de cenários poderia auxiliar a empresa no seu processo de tomada de decisão. A metodologia proposta neste trabalho avalia e identifica cenários representativos de incerteza nos cronogramas de planejamento estratégico de sondas offshore, a fim de reduzir o número de cenários utilizados no cálculo da demanda por ferramentas e serviços. Com a utilização de técnicas não supervisionadas, como k-means e agrupamento hierárquico, foi identificado um subconjunto com os cenários mais representativos para a redução de cenários. A Distância de Wasserstein e a visualizações gráficas foram utilizadas para calcular a representatividade dos cenários selecionados e encontrar o melhor subconjunto. Além disso, o subconjunto de cenários proveniente da redução também foi utilizado para analisar o impacto da redução no cálculo da demanda. O Clustering Aglomerativo com Ward Linkage obteve os melhores resultados de clusterização e representatividade, resultando em um subconjunto de redução de 782 cenários. Para encontrar um conjunto mínimo representativo de cenários, foi utilizado o melhor método de agrupamento, junto com a Distância de Wasserstein, e por fim obtido um número de 343 cenários. Isto apresenta uma redução de 84 por cento no tempo de execução do cálculo da demanda, com o erro maior de 11 por cento no cálculo da demanda. / [en] Material resource planning is an integral part of supply chain management. The tasks in the supply chain need materials and resources to be executed, thus, allocating resources correctly is an important part of task scheduling. Specifically, construction tasks for subsea wells require the use of resources, such as rigs, and planning the schedule of these operations involves the sizing of various materials and services necessary for their execution. This study is motivated by real-life scheduling planning from a large Oil and Gas company that estimates the demand for materials and services stochastically due to the uncertainties associated with the tasks in their start dates and durations. The calculation of the demand is subject to the current schedule that the company has and a set of rules that indicate allocation conditions, logistics parameters, disembarking conditions, and dependencies to allocate the tools and services needed for each task and estimate their quantity and how many days they will be used. These sets of tools and rules can change depending on the user and their operation knowledge. Additionally, the company uses a large number of scenarios, which results in extremely high computational times and impacts operational decision-making. In this context, scenario reduction could assist the company in its decision-making process. The methodology proposed in this work evaluates and identifies representative scenarios of uncertainty in strategic planning schedules of offshore rigs in order to reduce the number of scenarios used in the calculation of the demand for tools and services. With the use of unsupervised techniques, such as k-means and hierarchical clustering, we identified a subset with the most representative scenarios for the scenario reduction. The Wasserstein Distance and graphical visualization were used to measure the representativeness of the selected scenarios and find the best subset. Moreover, the scenario reduction subset was also used to analyze the impact of the reduction in the demand calculation. The Agglomerative Clustering with Ward Linkage (hierarchical clustering) obtained the best clustering evaluation and representativeness metrics, resulting in a selected subset of 782 scenarios. To find a minimal representative set of scenarios, the best clustering method and the Wasserstein Distance were used, resulting in a number of 343 scenarios. This presents a reduction of 84 percent in the execution time of the demand calculation, with the highest error of 11 percent in the demand calculation.

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