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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

"Influência da mochila em parâmetros dinâmicos, cinemáticos e fisiológicos da locomoção de carteiros pedestres" / DYNAMICS, KINEMATICS AND PHYSIOLOGICALS EFFECTS OF USING DIFFERENTS TYPES OS MAILBAGS

Germano Mongeli Peneireiro 11 April 2006 (has links)
O objetivo deste estudo foi determinar a influência das características de três tipos de mochila através de parâmetros biomecânicos e fisiológicos selecionados. Foram voluntários 49 carteiros (30±7 anos, 1,74±0,62 m e 72,6±11,8 kg), que utilizaram 3 tipos de mochilas: mochila lateral simples (MLS), mochila lateral com cinto pélvico (MLCP) e mochila dupla com cinto pélvico (MDCP). Os sujeitos andaram durante 10 minutos sobre esteira rolante Trotter instrumentada com duas plataformas de força de reação do solo Kistler, utilizando um analisador de gases que analisou os gases expirados. As variáveis cinéticas da locomoção apresentaram diferenças significativas entre as mochilas. As variáveis cinemáticas não mostraram diferenças significativas. A ventilação apresentou diferenças entre MLCP (23,2±5,4 L · min-1) e MLS (22,5±5,0 L · min-1) e MDCP (22,3±4,8 L · min-1) e o consumo de oxigênio apresentou diferenças entre MDCP (14,6±4,1 mL · kg-1 · min-1) e MLS (15,1±3,6 mL · kg-1 · min-1) e MLCP (15,2±4,3 mL · kg-1 · min-1). Os dados dinâmicos apontaram para benefícios do uso da MLS, e os dados fisiológicos apontaram para benefícios do uso da MDCP. Embora os dados tenham apresentado diferenças estatísticas, estas não foram de magnitudes representativas, assim, a MDCP parece induzir maior demanda metabólica e a MLS menor estresse físico. / The aim of this study was to determine the influence of the satchel construction characteristics in selected biomechanical and physiological parameters during the accomplishment of the locomotion of mailmen pedestrians. 49 mailmen had been voluntary (30±7 years, 1.74±0.62 m and 72.6±11.8 kg), which had used 3 types of satchels, simple lateral satchel (MLS), lateral satchel with pelvic belt (MLCP) and double satchel with pelvic belt (MDCP). The subjects had walked 10 minutes on Trotter treadmill instrumented with two Kistler force platforms, using a gas analyzer that made analyzes of the exhaled gases. Fy1 presented differences between MLS (1.35±0.10) and MLCP (1.37±0.11) and MDCP (1.37±0.10), like others FRS parameters. The step and strike lengths had not been sensible to the different satchels. The VE presented differences between MLCP (23.2±5.4 L · min-1) and MLS (22.5± 5.0 L · min-1) and MDCP (22.7±4.8 L · min-1) and the VO2, presented differences between MDCP (14.6± .1 mL · kg-1 · min-1) and MLS (15.1±3. 6 mL · kg-1 · min-1) and MLCP (15.2±4.3 mL · kg-1 · min-1). The dynamic data had pointed to benefits using MLS, but the physiological data had indicated to benefits using MDCP. Although the data have presented statistical differences, but these had not been representative magnitudes, thus, the MDCP seems to induce bigger metabolic demand and MLS the lesser physical stress.
112

Proposta de equipamento para medição dos fenômenos relativos à qualidade da energia elétrica utilizando conceitos de instrumentos virtuais / Power quality measuring equipment proposal based on virtual instruments conception

Gleison Melhado Matana 15 April 2008 (has links)
Este trabalho apresenta um estudo da literatura pertinente sobre qualidade da energia elétrica. O estudo apresentado está baseado na evolução do tema em nível nacional e internacional, buscando explicar o conceito dos principais fenômenos e selecionar as recentes resoluções e normas que regem os princípios de medição e os limites dos distúrbios eletromagnéticos que os caracterizam. As normas da IEC foram selecionadas para a aplicação na construção de um protótipo de um medidor de qualidade da energia elétrica, onde o princípio construtivo é o de instrumento virtual por sua flexibilidade de arquitetura. A implementação do protótipo dá-se em um microcomputador padrão de mercado pelo software LabVIEW, através de vários módulos independentes para cada distúrbio a ser medido. Os resultados numéricos das simulações executadas frente a cada distúrbio, gerando comparações entre valores aplicados e valores medidos são apresentados em forma de tabelas com seus respectivos erros percentuais para cada grandeza de cada módulo. / This dissertation presents a study of existing literature about power quality. The study presented is based on a theme evolution in national and international environment, trying to explain the main phenomenon conceptions and select the most recent standards that rule the measurement conceptions and the electromagnetic disturbances limits that characterize it. The IEC standard were selected to build a prototype of a power quality measure device where the construction conception is a virtual instrument because it has a flexible architecture. The prototype implementation was made from a common computer by the LabVIEW software through some independent modules for each disturbance to be measured. The numerical results of executed simulations of each disturbance generating comparisons between applied values and measured values are presented as tables within their percentage error for each phenomenon of each module.
113

Nekonvenční metody měření ve fotometrii / Unconventional Methods of Measurement in Photometry

Škoda, Jan January 2011 (has links)
This thesis deals with an unconventional possibility of measuring photometric values and the work is based on analysis of luminance made by commercially available digital photo camera. In the first part is represent an overview of current methods for measuring the photometry. You also can see the basic photometric values and required instrumentation needed to measure them. The focus of the work is concentrated on the description of the problems associated with setting the correct luminance of digital photography. It describes the dependency and correction procedures for calculating fixed luminance ratios of the individual images. The last part of this thesis is devoted to the possible use in practice, especially in the analysis of luminance of objects, luminaires and light sources. It also deals with an alternative description of luminaire and light sources to replace the luminous intensity curve etc.
114

Dynamic viscoelastic properties of advanced magnetic tapes

Berry, Robert D. 01 January 2012 (has links)
The purpose of this thesis is to analyze the viscoelastic properties of current large digital storage magnetic tape materials, using a custom ultra-low frequency dynamic mechanical analyzer (DMA). Through the correlated effects of frequency and temperature, the long term mechanical properties of the magnetic tape can be simulated and used for predictive analysis of long term storage quality and stability of each individual tape given applicable storage conditions. Two magnetic tapes of primary interest reviewed in this paper are both current leading high capacity tapes, one having a poly(ethylene naphthalate) or PEN substrate and the other an aromatic polyamide or ARAMID substrate. The phase angle between the two signals and the peak strain based elastic modulus (E) were then used to determine the storage modulus (E'), loss modulus (E"), and the loss tangent (tan 8). These viscoelastic characteristics of the material were determined for each individual experimental sample. The combined data was then used to create comparative plots of each sample type allowing for a more conclusive look at the magnetic tape properties under the given conditions. It is found that viscoelastic deformation, or energy loss in the material, increasingly occurs at low frequencies. These experiments also verify that viscoelastic loss also occurs due to molecular orientation and can have a large impact on results. A final comparison is also made between the two leading tape materials commonly used in industry currently by taking a direct look at relative loss in conjunction with the materials overall complex elastic modulus. This allows a more definitive strength comparison of the defined materials · under given conditions.
115

Analýza LAN sítě s následnou simulací v prostředí Opnet Modeler / Analysis of LAN Network followed by Simulation in Opnet Modeler Environment

Skopal, Jakub January 2009 (has links)
This thesis deals with the exploration of possibilities of LAN analysis with the use of the hardware analyzer Finisar TGHs from the Finisar Corporation Company. As a monitored network was choosed the local computer network in the laboratory PA-249 at the Department of Telecommunications, which is located at the Faculty of Electrical Engineering and Communication, Brno University of Technology. All results acquired from the complex long-term monitoring of the choosed LAN network are described in this thesis. Further, the thesis is focused on the simulation and analysis of the model of this network that was created in the simulation environment Opnet Modeler. The data obtained from the real LAN monitoring were used as a basis of an operating simulation of the transmission abilities and features of the real LAN network. The last part of the thesis describes the verification of the transmission capabilities and characteristics of the real LAN. Verification was performed in Opnet Modeler, where the network has been analyzed in detail.
116

Řídící a diagnostický systém sběrnice I2C / Control and Diagnostic System for I2C Bus

Juhás, Miloš January 2011 (has links)
The objective of this diploma thesis is design and realization of I2C bus analyzer. I2C bus protocol is briefly described, together with means of connecting devices to the bus. Next the basic requirements for I2C bus analyzer are defined. Then the design of hardware I2C-to-USB converter including block description is proposed. The chapter dedicated to converter firmware describes method of communication with PC, decoding of intercepted commands and principles of master, slave and passive mode of bus monitoring. The last part is focused on operation software and its structure. Described are individual interfaces, most notable classes and default plugin modules.
117

Spektrální analyzátor N1996A-503 a nejistoty měření / Spectrum Analyser N1996A-503 and Measurement Uncertainty

Trojan, Martin January 2011 (has links)
The main target of this master’s thesis is to introduce the reader with the spectrum analyzer, Agilent N1996A CSA. This work explains all the functions of this measuring instrument, control elements and presents some technical parameters. The next part of this thesis deals with the measurement of coaxial cables, so that is why a whole chapter is devoted to coaxial cables and conductors in general. The rest of this thesis deals with issues of measurement uncertainties. This part contains the general procedure for the evaluation of uncertainty, followed by a practical part. The practical part contains measurement of distance to fault and return loss. Measurements were made on 4 samples of coaxial cable. At the end of the practical parts the measured values including the uncertainties and results are summarized in the final paragraph.
118

Univerzální logický analyzátor / Generic logic analyzer

Tajč, Martin January 2013 (has links)
The aim of the project is to design a generic logic analyzer based on an FPGA. The analyzer should be able to analyze protocols such as I2C, SPI, RS232, RS485 and GPIO. The captured data can be observed using an embedded graphical display or using a PC. The PC can be used to control the analyzer and to save the captured data. The thesis is divided into several parts. First, the basic structure of the analyzer is described including detailed description of its particular components. Later on, the most common protocols that can be decoded using the analyzer are described. Finally, the FPGA subsystem and microcontroller application are presented together with corresponding source codes.
119

Analyzátor sběrnice s hradlovým polem Spartan 3 / Bus analyzer with Spartan 3

Galia, Jan January 2013 (has links)
This thesis deals with designing and realisation of a bus analyzer. The analyzer is programmed into Spartan-3AN XC3S50AN programmable logic device. The design includes a SRAM parallel memory and a graphical LCD display. Data output is realized through USB, microSD memory card and VGA. The thesis also describes the use of a software microprocessor PicoBlaze for the control of the LCD display and user interface. The last part deals with a test application using an 8-bit microcontroller connected to an alphanumeric display and a discussion over the results.
120

Univerzální modul s připojením na ethernet / Universal ethernet module

Řeháček, Tomáš January 2015 (has links)
This master’s thesis deals with creating a universal module with Ethernet interface and its using for digital values measurement. The main module components are gate array FPGA, microprocessor, PHY chip and RJ45 connector. Printed circuit board is in this thesis designed in Eagle. The chase for board is drawn in SketchUp and printed on a 3D printer. There is a code implemented in created universal module that is performing the function of logic analyzer. Data measured by the analyzer are sent to the Ethernet using UDP/IPv4 protocol. The last part is creating an application in C# to display the measured waveforms on a PC.

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