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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.
71

Paving the Randomized Gauss-Seidel

Wu, Wei 01 January 2017 (has links)
The Randomized Gauss-Seidel Method (RGS) is an iterative algorithm that solves overdetermined systems of linear equations Ax = b. This paper studies an update on the RGS method, the Randomized Block Gauss-Seidel Method. At each step, the algorithm greedily minimizes the objective function L(x) = kAx bk2 with respect to a subset of coordinates. This paper describes a Randomized Block Gauss-Seidel Method (RBGS) which uses a randomized control method to choose a subset at each step. This algorithm is the first block RGS method with an expected linear convergence rate which can be described by the properties of the matrix A and its column submatrices. The analysis demonstrates that RBGS improves RGS more when given appropriate column-paving of the matrix, a partition of the columns into well-conditioned blocks. The main result yields a RBGS method that is more e cient than the simple RGS method.
72

Uma interface eletrônica e computacional para medições a três coordenadas / A electronic and computational interface for coordinate measurement

Marques, Alessandro 08 December 2003 (has links)
As Máquinas de Medir a Três Coordenadas (MM3Cs) desde sua criação evoluíram sensivelmente, entretanto poucas foram as modificações estruturais observadas. Hoje, para fabricantes de máquinas destacarem-se no mercado, são necessários grandes investimentos na busca de novos materiais estruturais e no desenvolvimento de programas computacionais cada vez mais versáteis. O sistema eletrônico e os programas computacionais utilizados durante as medições são inacessíveis e rígidos. Estes aplicativos normalmente não podem ser analisados nem modificados pelo usuário. São exemplos clássicos desta rigidez as características préestabelecidas pelo programa, ou métodos de ajustes utilizados na definição das grandezas. Este trabalho tem por objetivo exibir a interface eletrônica e computacional que quebra essa rigidez e permite a aquisição dos sinais das escalas da MM3C, possibilitando o desenvolvimento de novos aplicativos computacionais. O sistema foi aplicado em uma MM3C do tipo Ponte Móvel. Foi desenvolvido um programa computacional, MaqMed 2000, que utiliza os valores dos pontos coordenadas capturados no volume de trabalho da MM3C, e faz a compensação das coordenadas dos pontos utilizados, através das equações do Modelo Reduzido de Sintetização de Erros (MRSE). A avaliação da compatibilidade do dispositivo construído foi feita através do MaqMed 2000 em situações práticas. Foram tomados pontos no perfil de artefatos-padrão e os pontos ajustados através de duas rotinas, uma com e outra sem compensação dos erros. Os artefatos foram medidos em várias posições no volume da MM3C e averiguada a proximidade entre os resultados compensados e os não compensados, ao valor calibrado do artefato. O sistema desenvolvido permitiu compensar os erros em até 98% para compensação bidimensional e 87% para tridimensional. / Since the advent Coordinate Measuring Machines (CMMs) have improved substantially. However, only a small number of structural modifications were observed. Nowadays, considerable capital expenditure is needed to keep CMM builders competitive. Most important research fields concern structural material and production of more flexible and versatile software. The electronic system and the software used during measurement with CMM are rigid and inaccessible and no user modification is permitted. Typical examples are the predetermined software features and curve fitting methods used on the magnitudes definition process. This research aims to exhibit an interface that copes with the system stiffness and enables signal acquisition from the scales of the CMM, allowing the development of new types softwares. The proposed system was implemented on a moving bridge type CMM. A program that uses the values of the coordinate points obtained from the CMM work volume was created. The software MaqMed 2000 performs the compensation of the coordinates of the used points by means of synthesized errors equations. Evaluation of the performance of the built device was carried out using MaqMed 2000 in practical situations. Data sets were collected along the profile of artefacts and fitted by means of two routines, one with error compensation and the other not compensated. Artefacts were measured in several locations in the whole volume of the CMM. The proximity between the compensated and noncompensated results with respect to the calibrated artefact value was examined. The developed system allowed for error compensation of 98% for bi-dimensional compensation and 87% for tri-dimensional compensation.
73

Validity of Linear Position Transducers Versus the Optotrak Certus 3D Motion Capture System

Unknown Date (has links)
The purpose of this study was to investigate the validity of linear position transducers (LPTs), The Open Barbell System (OBS) and Tendo Weightlifting Analyzer System (TWAS), in comparison to criterion measure Optotrak Certus (OC3D). Further, we aimed to compare LPTs against each other. Twenty-five resistance-trained males were recruited, and reported to the laboratory for one day of data collection. Subjects performed one-repetition maximum (1 RM) testing of the squat, then had a standardized rest before completing one set to failure with 70% 1 RM. There was no significant difference in average velocity (AV) between either LPT vs. OC3D. T-tests revealed significant differences between LPTs and OC3D peak velocity (PV) (OBS: p=0.02080; TWAS: p<0.01). A significant difference was detected between OBS and TWAS PV (p<0.01). OBS and TWAS demonstrated concurrent validity compared to OC3D for AV (OBS: p=0.2014; TWAS: p=0.5466). Neither LPT was a valid measure ofPV (OBS: p=0.0208; TWAS: p<0.01). / Includes bibliography. / Thesis (M.S.)--Florida Atlantic University, 2016. / FAU Electronic Theses and Dissertations Collection
74

Estudo dos erros cíclicos nas máquinas de medir a três coordenadas / not availalbe

Nakazato, Márcia Kimie 06 November 2003 (has links)
Os erros cíclicos nas escalas das máquinas de medir a três coordenadas (MM3Cs) exercem influência significativa nos resultados das medições efetuadas em comprimentos pequenos. Um dos fatores que contribuem para a ocorrência dos erros cíclicos é a acuracidade limitada dos métodos utilizados na fabricação de escalas. As MM3Cs utilizam escalas desenhadas e fabricadas por métodos fotográficos ou riscadas em máquinas tipo \"step and repeat\". Ambos os métodos produzem um erro sistemático entre traços sucessivos. Desta forma, a medida que o número de traços aumenta as parcelas do erro sistemático somam-se e quando atingem um determinado valor este erro é compensado. Esta correção é feita a cada distância cujo valor corresponde ao de um período cíclico de baixa freqüência e o processo repete-se até que toda a escala seja riscada. Outro fator que contribui para a existência dos erros cíclicos origina-se da resolução exigida pela MM3C, que é sempre bastante alta e ultrapassa as capacidades existentes atualmente para fabricação de escalas. O que se faz para lidar com o problema da resolução é subdividir eletronicamente o espaço entre traços consecutivos da escala. Esta divisão eletrônica está associada a um sinal seno gerado pelas franjas de Moiré. A digitalização e subdivisão deste sinal geram erros periódicos, também conhecidos como erros cíclicos de alta freqüência. Embora diversos erros das MM3Cs tenham sido largamente estudados, ainda hoje, não foi realizada uma observação sistemática para que se tenha a exata medida da influência dos erros cíclicos, na medição a três coordenadas. Para suprir essa necessidade e contribuir na busca de novos métodos de avaliação, este trabalho apresenta os procedimentos de medição dos erros cíclicos de baixa e de alta freqüência, bem como a aplicação de Análise de Fourier aos conjuntos de dados obtidos. A medição da distância entre as linhas consecutivas da régua móvel da MM3C também foi realizada e os resultados comprovaram a existência dos erros de fabricação, a ocorrência de compensação periódica e também sugeriram os erros de subdivisão eletrônica. Além disso, no levantamento dos erros cíclicos de baixa freqüência foi confirmada a existência de um período cíclico de quatro milímetros. / Cyclic errors in scales of Coordinate Measuring Machines (CMMs) have a significant influence in measuring results on a very small displacement hindering most of the measuring tasks. One of the factors that contribute to the appearance of the cyclic errors is the limited accuracy of the used manufacturing methods of the scales. CMMs use scales drawn and manufactured by photographic methods or marked in step and repeat machines. In both methods the distances between succeeding lines are prone to systematic errors and therefore, with the increasing of the number of lines systematic errors are added up. Error compensation is provided when the amount of errors reaches a predetermined value. The error correction made at predetermined lengths defines a period what one can call the low frequency cyclic error. This process must be repeated all along the scale. Another factor that contributes to the existence of cyclic errors originates from high resolution required by CMM that goes beyond the existent manufacturing capacities of scales. This problem is somewhat solved by means of an electronic signals splitting up. The electronic sign obtained as two consecutive lines on the scale is probed can be associated to a sine signal what is generated by Moiré type fringes. Digital conversion and electronic division of these signals also generate periodic errors and can be called high frequency cyclic error. Although several types of errors in CMMs have been largely studied,there is a lack regarding the cyclic errors. A huge need for a systematic study and observation of these errors is needed to permit an exact measure of its influence on coordinate measurements. To cope with the urgent need and to contribute in the search for new evaluation methods of the cyclic errors, this work presents a measuring procedure of low and high frequency cyclic errors and the application of Fourier Analysis to the testing data. Measurements of distances between consecutive lines of the scale were also obtained and the results have shown the existent manufacturing errors and suggested frequencies and period of errors of electronic division. A cyclic period of four millimeters was confirmed in the low frequency tests.
75

Método para o georreferenciamento de mapas urbanos baseado na atribuição de pesos aos pontos de controle / Method for the georreferencing of urban maps based on the attribution of weights to the control points

Santos, Adriana Goulart dos 03 September 2009 (has links)
Para o georreferenciamento das informações extraídas dos mapas digitais são usados modelos matemáticos de transformação geométrica de coordenadas. O desempenho da transformação de coordenadas está diretamente relacionado à exatidão das coordenadas dos pontos de controle identificados no mapa, uma vez que devido ao uso da tecnologia GNSS, não existe mais a dificuldade de se medir com exatidão coordenadas de pontos no terreno. Por esta razão, é possível obter um georreferenciamento admissível se as coordenadas dos pontos de controle forem posicionadas com exatidão sobre o mapa. Entretanto, como na maioria dos municípios do Brasil, os mapas são antigos, ou seja, desatualizados, existe uma dificuldade de se localizar pontos de controle bem determinados dentre os elementos geográficos representados no mapa. Dependendo da qualidade do mapa e pelo modo como foram identificadas no mesmo, estas coordenadas podem apresentar diferentes graus de confiabilidade, em função de suas exatidões. Tal fato, se não for levado em conta, pode prejudicar o desempenho da transformação de coordenadas, e dependendo da escala do mapa, inviabilizar um projeto ou estudo que dependa de uma boa exatidão de coordenadas de pontos oriundas de um produto cartográfico georreferenciado. Para evitar que o desempenho da transformação de coordenadas comprometa a fidelidade do georreferenciamento gerado, é importante que cada coordenada receba um peso apropriado de acordo com a sua exatidão. Neste contexto, o principal objetivo desta pesquisa foi desenvolver um método, validado através de um estudo de caso, que proporcionasse em função da exatidão das coordenadas dos pontos de controle identificadas no mapa digital, um resultado de georreferenciamento admissível a partir do modelo matemático empregado para transformação de coordenadas. Para isso, foi estudado como atribuir o peso ao ponto de controle em função da sua exatidão. A partir disso, o desempenho da transformação de coordenadas usando pesos foi avaliado tanto num mapa de calibração, de boa qualidade, quanto num mapa cuja qualidade posicional era desconhecida. Em ambos os mapas foram realizadas as mais variadas avaliações. Em todas as avaliações efetuadas o desempenho da transformação de coordenadas foi melhor quando foram atribuídos pesos aos pontos de controle em função da sua exatidão. Esta pesquisa levantou uma questão até então desconsiderada, que é a importância de se atribuir pesos às coordenadas dos pontos de controle em função da sua exatidão no mapa digital. O resultado do georreferenciamento se torna admissível quando esta consideração é levada em conta. / The mathematical model for the geometric transformation of coordinates is used to georreference information extrated from digital maps. The performance of coordinate transformation models is directly related to accuracy of control points identified in the map, since by means of the utilization of GNSS technology, it is not difficult to measure the coordinates of a point in the ground with accuracy. For this reason, it is possible to obtain a reliable georreferencing if the coordinates of the control points are accurately positioned on a map. However, as most of brazilian municipal districts maps are old and out-of-date, it is difficult to locate a point accurately out of the geographic elements represented in the map. Depending on both the quality of the digital map and the technique used to locate the points, such coordinates may show distinct levels of reliability as a function of their accuracy. If the different accuracy of the control points is not taking into account, the performance of the coordinate transformation model can be reduced. Depending on map scale, this difference can make impracticable a study that depends on a good accuracy of the coordinates of points obtained from a georreferecend cartographic product. In order to avoid that the performance of the coordinate transformation model reduce the reliability of the georreferencing, it is important that each coordinate receives an appropriate weight according to its accuracy. In this context, the objective of this research was to develop a method, validated through a case study, that could impart reliability to georreferencing, as a function of the accuracy of the coordinates of the control points identified on a map, using a mathematical model to coordinate transformation. The key-point is to attribute a weight to each control point related to its accuracy level. The performance of this procedure was evaluated both for a high quality, standard map, and for a map with unknown quality. Different evaluations were performed and the best results were obtained using the procedure of attributing weights to the control points related its accuracy. As a contribution for the academic and technical areas, this research brought light to a question not considered until now, that is the importance of attributing weights to the coordinates of the control points as a function its accuracy in the digital map. Georreferencing becomes more reliable when this question is taken into account.
76

Uma metodologia para o cálculo da incerteza das medições a três coordenadas / A description of a methodology to calculate the uncertainty measurements to three coordinate

Camargo, Rosana 25 August 2000 (has links)
O valor de uma grandeza é determinado por um conjunto de operações que caracterizam a medição. O resultado obtido por estas operações é o valor da grandeza, que nunca é o verdadeiro, porque toda medição possui erros de natureza sistemática ou aleatória, que acrescenta uma incerteza ao resultado. Assim, todo resultado de uma medição deve incluir informações sobre a sua incerteza, isto é, sobre o intervalo dentro do qual se estima que esteja o valor verdadeiro. Um consenso internacional sobre o assunto levou à elaboração da ISO-GUM (Guia para a Expressão da Incerteza de Medição), que fornece regras para a obtenção da expressão da incerteza da medição de grandezas físicas. No entanto, quando se trata da incerteza de medição por coordenadas, isto é, a incerteza na localização de um ponto no espaço, determinado através da indicação de uma máquina de medir a três coordenadas (MM3C), o problema é bem mais complexo. Assim, o objetivo deste trabalho é descrever uma metodologia para calcular a incerteza da medição por coordena das. Este cálculo envolve a calibração direta da máquina para a avaliação dos 21 possíveis erros geométricos, a análise destes erros para a determinação das equações que permitem calcular as incertezas de cada erro individualmente, e a análise geométrica da estrutura da máquina para determinar as equações de sintetização Ex, Ey e Ez, nas direções de seus eixos. Para definição da metodologia as equações que descrevem a variância combinada dos erros avaliados na calibração, foram substituídas nas equações que definem a variância do erro volumétrico das componentes Ex, Ey e Ez, dando origem às equações gerais que permitem determinar a incerteza do resultado da medição em uma MM3C. / The value of a magnitude is determined through a group of operations that characterize it. The result obtained by these operations is the value of the magnitude, and this value is never the true one because all measurements undergo errors of systematic or random nature, which increase an uncertainty to its result. Thus, all measurement result should include information about its uncertainty, that is, about the interval of values inside of which is considered that the true value is. An international accord, on that subject, allowed the elaboration of the ISO-GUM (Guide for the Expression of the Uncertainty of Measurement), that supplies rules for obtaining the expression of the measurement uncertainty for calibrations, linear dimensional measurements, among others. However, when the task is to estirnate the uncertainty of coordinate measurements, that is, the uncertainty of a point in the space, determined through the indication of a coordinate measuring machine (CMM), the problem is much more complex. Thus, the objective of this work is the description of a methodology to calculate the uncertainty measurements indication of a three coordinate measuring machine. This involves the direct calibration of the machine for the evaluation of the 21 possible geometric errors, the error analysis for defining the equations that allow to estimate the uncertainties of each error individually and the geometric analysis of the machine structure for determining the error synthetization equations Ex, Ey and Ez. The equations that describe the uncertainty of the geometric error measurements were substituted in the uncertainty equations of Ex, Ey and Ez, creating the general equations that allow to determine the uncertainty of the result of a measurement with a CMM.
77

Phase co-ordinate bond graph analysis of multiport energy Systems

Salleh, M. Ridzuan January 1974 (has links)
The analysis of unbalanced power system problems using the method of phase co-ordinates by which the phase quantities are preserved has obvious practical advantages over the transformation methods requiring the phase quantities to be substituted by, for example, symmetrical component and d-q quantities. Since the physical identity of the system is maintained in the phase frame of reference, the matematical models of the system can be subjected to actual operating constraints enabling a unified approach to be adopted in the study of both symmetrical and unsymmetrical conditions. In this thesis the bond graph techniques are used to model power system components in terms of their phase co-ordinates. The bond graph structure, which is based on energy continuity and power balance, classifies system and sub-systems, with respect to the number of energy ports through which energy or power is exchanged with the environment as well as in terms of the particular internal energy transformations involved. The use of bond graphs for the analysis of non-linear electromagnetic systems has resulted in the evolution of a uniform diagramatic structure which, represents in a single diagram the basic field properties such as the magneto-motive force and the flux linkages together with the conjugate circuit power variables, voltage and current. As an extension of this ideal the general n-port electromagnetic and electrostatic field systems are derived in bond graph notations. A very desirable feature of this method of presentation is that there exists a one-to-one-correspondence between the bond graph and a computation structure which may be used for the purpose of simulation by either analogue or digital computers. The general n-port electromagnetic and electrostatic field systems form the basis for the effective modelling of power system components such as rotating machines, transformers and transmission lines. In the investigations of earth faults, these models are simplified in accordance with the need of the particular study but are sufficiently accurate representations to allow predictions on the overall system behaviours. The bond graph approach is ideally suited to expedite the modelling of dynamic interacting energy systems and when used in conjunction with the computation structure can provide the simulation technique required to model accurately the non-linear behaviours of multiport electromechanical energy converters. The effects of magnetic saturation in synchronous generators are presented in detail.
78

Synthesis and reactivity of low coordinate nickel(I) complexes bearing ring expanded N-heterocyclic carbene ligands

Poulten, Rebecca January 2015 (has links)
This thesis describes the development of nickel(I) complexes incorporating ring expanded N-heterocyclic carbene (RE NHC) ligands and examines their electronic characterisation, activation of O2, reactivity and catalytic applications. A series of three coordinate, paramagnetic Ni(I) complexes of the form Ni(RE NHC)(PPh3)Br (1 – 10) were prepared by comproportionation of Ni(COD)2 and Ni(PPh3)2Br2 in the presence of RE NHCs. The RE NHCs employed varied in the degree of ring expansion (6-, 7- and 8-membered), extent of N-substituent steric bulk (Mes, oTol, oAnis) and the donor/acceptor properties of the carbene (diamino vs. diamido). EPR and DFT electronic characterisation of 1 – 10 confirmed that the unpaired electron was located on the nickel ion in a mixed orbital of predominantly 3dz2 character. Yellow solutions of 1 or 6 (RE NHC = 6Mes and 7Mes respectively) immediately became purple in the presence of O2 due to O2 activation and incorporation of the oxygen atoms as bridging ligands resulting from C-H activation/oxygenation of an RE NHC N-substituent. This generated the dimeric Ni(II) complexes Ni(6/7Mes)Br(µ-OH)(µ-O-6/7Mes)’NiBr (6Mes = 13; 7Mes = 14). Mass spectrometry demonstrated that the doubly activated complexes [NiBr(µ-O-6/7Mes)’]2 (15 and 16 respectively) were also formed in the reactions. UV-vis spectroscopy revealed the reactions took place rapidly, even at 190 K. Contrasting reactivity was observed when 2 or 7, bearing the less sterically encumbered N-oTol substituents 6oTol and 7oTol respectively, were exposed to O2, which led to the ligand redistribution products NiII(6/7oTol)(PPh3)Br2 (17 and 18 respectively). The less electron rich diamido analogue containing 6MesDAC (5), underwent dissociation and oxidation of the RE NHC and PPh3 ligands. Attempts to abstract the bromide from 1 generated novel two and three coordinate Ni(I) products. Reaction with additional 6Mes produced the two coordinate cation [Ni(6Mes)2]+ (19), which could be reduced with KC8 to Ni(6Mes)2 (20). SQUID analysis of 19 revealed it to be the first example of a nickel containing mononuclear single molecular magnet (SMM). Addition of [Et3Si]+ to 1 followed by work up in toluene led to the isolation of the Ni(I)-(η2-toluene) complex [Ni(6Mes)(η2-C6H5CH3)]+ (21). Mesitylene generated the analogous [Ni(6Mes)(η2-C6H3(CH3)3)]+ (23), but neither 1,4-xylene nor naphthalene gave isolable products. In all cases, cocrystallisation of [6MesH]+…arene was observed in variable amounts, which compromised reaction studies of the Ni-arene complexes. Removal of bromide from 1 with TlPF6 in THF generated the solvent coordinated cationic species [Ni(6Mes)(PPh3)(THF)]+ (24). Attempts to remove the ligated THF molecule were unsuccessful, however, it could be directly substituted by CO to form [Ni(6Mes)(PPh3)(CO)]+ (26). Similarly to 1, complex 24 activated O2, generating a dimer analogous to the singly activated complex 13 (Ni(6Mes)(PPh3)(µ-OH)(µ-O-6Mes)’NiBr (25)). Reactivity of 1 with NaBH4 produced [Ni(6Mes)(κ2-BH4)]2 (28), a Ni(I) dimer bridged by two BH4 ligands. The catalytic efficiency of neutral 1 in Kumada cross-coupling of aryl halides and PhMgCl or MesMgBr was probed. Of note was the high activity towards both aryl chlorides and aryl fluorides. Comparisons with cationic 24, larger 7- (7) and 8-membered ring (8 and 9) variants and the Ni(II) complexes Ni(6Mes/6oTol/7oTol)(PPh3)Br2 (29, 17 and 18 respectively) revealed that 1 exhibited the highest reactivity of all the precursors.
79

Distributed Statistical Learning under Communication Constraints

El Gamal, Mostafa 21 June 2017 (has links)
"In this thesis, we study distributed statistical learning, in which multiple terminals, connected by links with limited capacity, cooperate to perform a learning task. As the links connecting the terminals have limited capacity, the messages exchanged between the terminals have to be compressed. The goal of this thesis is to investigate how to compress the data observations at multiple terminals and how to use the compressed data for inference. We first focus on the distributed parameter estimation problem, in which terminals send messages related to their local observations using limited rates to a fusion center that will obtain an estimate of a parameter related to the observations of all terminals. It is well known that if the transmission rates are in the Slepian-Wolf region, the fusion center can fully recover all observations and hence can construct an estimator having the same performance as that of the centralized case. One natural question is whether Slepian-Wolf rates are necessary to achieve the same estimation performance as that of the centralized case. In this thesis, we show that the answer to this question is negative. We then examine the optimality of data dimensionality reduction via sufficient statistics compression in distributed parameter estimation problems. The data dimensionality reduction step is often needed especially if the data has a very high dimension and the communication rate is not as high as the one characterized above. We show that reducing the dimensionality by extracting sufficient statistics of the parameter to be estimated does not degrade the overall estimation performance in the presence of communication constraints. We further analyze the optimal estimation performance in the presence of communication constraints and we verify the derived bound using simulations. Finally, we study distributed optimization problems, for which we examine the randomized distributed coordinate descent algorithm with quantized updates. In the literature, the iteration complexity of the randomized distributed coordinate descent algorithm has been characterized under the assumption that machines can exchange updates with an infinite precision. We consider a practical scenario in which the messages exchange occurs over channels with finite capacity, and hence the updates have to be quantized. We derive sufficient conditions on the quantization error such that the algorithm with quantized update still converge."
80

Ergonomia aplicada em posto de trabalho do operador de tratores : sistema para aquisição de coordenadas tridimensionais /

Silva, André Luis da, 1973- January 2009 (has links)
Resumo: A crescente demanda na aquisição de tratores agrícolas vem aumentando a concorrência entre os fabricantes e expondo a carência das empresas em produzir tratores agrícolas que possam atender as nececidades ergonômicas de pequenas e grandes propriedades rurais ampliando a opção do comprador com novos modelos que atendam às suas necessidades de uso. O lançamento de novos modelos de tratores agrícolas traz ao mercado nacional as mais recentes tecnologias ao posto de trabalho do operador de trator. A inserção de novas tecnologias na agricultura vem avançando constantemente em várias áreas, mas, especificamente no posto de trabalho do operador de trator agrícola, estas inovações não caminham na mesma velocidade, quando se utiliza de técnicas não tão atuais para avaliar com precisão o invólucro do operador de trator, dificultando, ainda, ao pesquisador a aquisição de equipamentos atualizados para a coleta de dados ergonômicos, principalmente para as coordenadas tridimensionais. Esta pesquisa teve como objetivo o desenvolvimento de um equipamento que possa coletar as coordenadas tridimensionais dos controles do posto de trabalho do operador de trator, automatizando a inserção dos dados diretamente ao computador e tendo maior precisão das medidas obtidas, eliminando os erros humanos de leitura e digitação. O equipamento proposto é composto de um sistema de angulação horizontal, vertical e um feixe de laser para medições diretas, sendo que os dados coletados por um módulo conversor da angulação, e um sistema de coleta sem fio para o feixe de laser. Com o propósito de coletar os dados, foi desenvolvido um programa computacional chamado de "Ergocoord", na linguagem de programação Delphi. Para os dados coletados foram utilizados tratores novos com potência média de 74 kW, visando não alterar as variáveis da pesquisa... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The growing demand in the purchase of tractors is increasing competition between manufacturers and exposing the lack of companies to produce farm tractors that can meet the ergonomic nececidades large and small farms extending the option buyer with new models that meet their needs use. The launch of new models of tractors brings to the domestic market the latest technologies to the job of the operator of tractor. The introduction of new technologies in agriculture has been advancing steadily in many areas but specifically in the workplace of the operator of an agricultural tractor, these innovations do not go the same speed when using such techniques do not present to evaluate accurately the RTB tractor operator, making it also the researcher to acquire updated equipment for the collection of ergonomic data, especially for three-dimensional coordinates. This study aimed to develop a device that can collect three-dimensional coordinates of the controls of the job of the tractor operator by automating the data is entered directly into the computer and with higher accuracy of measurements obtained by eliminating human error in reading and typing. The proposed equipment consists of a system of horizontal angle, vertical, and a laser beam to direct measurements, and the data collected by a converter module of the angle, and a collection system for wireless laser beam. In order to collect the data, we developed a computer program called "Ergocoord" in the Delphi programming language. For the data collected were used tractors with new average power of 74 kW in order not to change the variables of the research. In the valuation of the proposed equipment used two methodological processes, the traditional method of measurement proposed by the NBR / NM / ISO 5353 - Road rollers, tractors and agricultural and forestry machinery - Point of reference of the seat, and adapted it standard... (Complete abstract click electronic access below) / Orientador: João Eduardo Guarnetti dos Santos / Coorientador: Saulo Philipe Sebastião Guerra / Banca: Marcos Roberto Bormio / Banca: Cristiane Affonso de Almeida Zerbetto / Banca: Otavio Jorge Grigoli Abi Saab / Banca: Marco Antonio Rossi / Doutor

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