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Balotta, Graciano Augusto Peviani [UNESP]. "Análise de três métodos de estimativa da evapotranspiração de referência para a região de Pradópolis - SP." Universidade Estadual Paulista (UNESP), 2011. http://hdl.handle.net/11449/88228.
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balotta_gap_me_jabo.pdf: 233319 bytes, checksum: 23b0129b8a38f43d1dd6a512cb94ef29 (MD5)O objetivo desse trabalho foi avaliar três métodos de estimativa da evapotranspiração de referência (Hargreaves, Radiação Solar e Makkink), comparando-os com o método de Penman-Monteith, recomendado pela Organização das Nações Unidas para a Alimentação e Agricultura (FAO) como método padrão para estimativa da ETo, para o município de Pradópolis - SP. Para esse fim foi instalada no posto agrometeorológico da cidade de Pradópolis - SP uma estação meteorológica automatizada. Por intermédio desta estação foram obtidas medidas da radiação solar global, temperatura do ar, umidade relativa do ar e velocidade do vento. A análise dos resultados foi feita por uma técnica que considera os erros da ET0. O resultado da avaliação dos métodos indica um melhor ajuste para estimativa da ETo para o método de Hargreaves. Os métodos de Makkink e Radiação Solar não obtiveram um ajuste satisfatório com o do Penman-Monteith. Para avaliar métodos de estimativa da evapotranspiração deve-se considerar os erros da estimativa da ETo, evitando possíveis erros de avaliação
The aim of this investigation was to evaluate two reference methods to Monteith method, recommended by the Food and Agricultural Organization of the United Nations (FAO) as the standard method for estimating ETo in Pradópolis - SP. To this data collection, an automated weather station was installed in the meteorological station at Pradópolis - SP. Through estimate evapotranspiration (Hargreaves, Radiation and Makkink), compared to Penman-this station, we obtained measures of global solar radiation, air temperature, relative humidity and wind speed. The analysis was done by a technique that considers the mistakes of ETo, which depends on the combination of the errors of the variables that make up the estimating equations, derived from the measurement instruments used to obtain these variables. The aftermath showed a better adjustment to Hargreaves. Makkink, and Radiation methods are different from Penman-Monteith, therefore, they cannot be compared. To evaluate methods to estimate evapotranspiration and avoid possible evaluation errors, ETo estimate errors must be considered
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Moneyhun, Sara E. "Optical pyrometry for noncontact temperature measurement." Thesis, This resource online, 1990. http://scholar.lib.vt.edu/theses/available/etd-01262010-020330/.
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Wang, Gaoxuan. "Development of photonic instruments for measurement of aerosol optical properties." Thesis, Littoral, 2018. http://www.theses.fr/2018DUNK0470.
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À cause de leur diffusion et de leur absorption des radiations solaires, les aérosols atmosphériques jouent un rôle important dans l'évolution du climat terrestre. Les techniques de mesure actuelles apportent certes, des connaissances, sur le forçage radiatif mais les résultats possèdent généralement de larges incertitudes, souvent du même ordre de grandeur que la valeur elle-même. Ces incertitudes sont causées par le manque de précision sur les données liées aux propriétés optiques estimées de ces aérosols (comme l'absorption, la diffusion ou l'extinction). Elles découlent principalement des techniques de mesures actuelles : à l'effet de chargement des filtres (lors de mesures classiques par filtres), aux mesures limitées par l'étendue spectrale des instruments, aux conditions d'échantillonnage différents lors de mesures séparées, etc. Dans ce travail de thèse, j'ai développé puis testé des instruments optiques et électroniques dans le but d'augmenter la précision des mesures des coefficients d'extinction et d'absorption des aérosols. (1) Deux spectrophones PhotAccoustique (PA) sont développés afin d'améliorer les mesures d'absorption des aérosols grâce à des mesures directes et sans filtres. Une première génération utilisant un rayonnement à 444 nm permet de réduire les incertitudes de mesure de 20-30% (obtenue par la technique d'échantillonnage par filtres) à 7,4% et 4,6% pour la détermination des coefficients d'absorption massique du carbone suie et de cendres volcaniques, respectivement. Transformé en spectrophone PA à multi-longueurs d'onde opérant conjointement à 444,532 et 660 nm, il permet alors de caractériser la dépendance spectrale du Coefficient d'Absorption d'Ångström (CAA). Les valeurs du CAA du carbone suie sont en accord avec les résultats publiés. Celles obtenues lors de l'analyse de deux échantillons de cendres volcaniques résultant de l'éruption du Eyjafjallajökull sont similaires au CAA du carbone brun,prouvent la présence d'importantes quantités d'éléments organiques. (2) Un extinctiomètre, basé sur le principe de la spectroscopie d'absorption en cavité à source large bande et incohérente (IBBCEAS), est ensuite développé afin de suivre l'évolution des propriétés optiques d'Aérosols Organiques Secondaires (AOS) produits par la photolyse du 2-nitrophénol dans une chambre de simulation atmosphérique de l'University College de Cork (Irlande). Leurs coefficients d'extinction et d'absorption sont suivis par cet extinctiomètre et un spectrophone PA durant tout le processus de production. Les évolutions des propriétés optiques des AOS confirment l'effet du vieillissement atmosphérique. (3) Une nouvelle architecture de détection synchrone est développé afin de rendre notre prototype plus léger, plus compact, mieux adapté aux applications in situ et plus particulièrement aux drones, techniques émergentes qui permettent de caractériser le profil vertical des aérosols dans l'atmosphère. Cette détection synchrone innovante, évaluée lors de la mesure de la concentration de NO₂ ambiant (niveau de concentration de quelques ppbv) possède une précision et une reproductibilité de mesures comparable à la détection synchrone SR830, commercialisée par la société Stanford Research Inc. L'évaluation précise de l'impact climatique des aérosols nécessite une quantification exacte et non biaisée de leurs propriétés optiques. À ce jour, elle reste un défi majeur dans la recherche sur les sciences de l'atmosphère et du changement climatique. Ainsi, des informations sur la taille des particules (liée à l'absorption sélective en longueur d'onde) nécessitent des mesures étendues sur de larges régions spectrales du rayonnement solaire principale. Le développement d'un albédomète large bande à haute précision, dédié à la mesure simultanée des coefficients d'extinction et d'absorption des aérosols est en coursAtmospheric aerosols are known to play an important role in earth climate by scattering and absorbing solar radiation. However, the aerosol radiative forcing effect is still known with large uncertainties (almost equal to the magnitude of the aerosol radiative forcing). The uncertainties are mainly caused by inaccurate estimates of aerosol optical properties (such as its absorption, scattering and extinction coefficients) using the currently available measurement techniques, with result in filter loading effect in classic filter technique, the uncertainty due to different sampling conditions for separate measurements of aerosol optical properties in combination of different techniques or due to the measurements at limited spectral wavelength ranges. My PhD work was carried out on the developments and applications of optical and electronic instruments for accurate measurements of aerosol extinction and absorption coefficient : (1) Photoacoustic spectrophones were developed for filter-free direct measurements of aerosol absorption with high accuracy. Measurements uncertainties down to about 7.4% and 4.6% (compared to about 20-30% in filter-based measurements) were achieved for the determination of mass absorption coefficients of black carbon and volcanic ash samples, respectively, using a single-wavelength PA spectrophone operating at 444 nm. A 3-wavelength PA spectrophone operating at 444,532 and 660 nm was developed and deployed for characterizing wavelength-dependent optical properties of aerosol absorption Ångström coefficient (AAC). The determined AAC of black carbon was well consistent with the previously reported value. Our AAC values of two volcanic ash samples from 2010 eruptions of Eyjafjallajökull, similar to the AAC of brown carbon, indicated abundant organic compounds in the volcanic ash samples. The developed multi-wavelength PA spectrophone was tested and validated in an intensive field campaign measurements of environmental particles in Grenoble (France). Side-by-side inter-comparison measurements using an aethalometer showed a lineat correlation of the measured aerosol absorption coefficients from both instruments. (2) An extinctiometer based on IBBCEAS was developed for study of optical properties of secondary organic aerosol (SOA) produced from photolysis of 2-nitrophenol in an atmospheric simulation chamber at University College Cork (Ireland). Simultaneous monitoring of the SOA extinction and absorption (in conjuction with a PA spectrophone) coefficients was performed during its whole production process, the measured evolutions of the SOA optical properties highlighted the atmospheric aging effect. (3) In order to render optical sensor lightweight and suitable for field applications, in particular for the newly emerging unmanned aerial vehicle (UAV) applications, a novel architecture of lock-in amplifier (LIA) was proposed and developed in the framework of this Phd Research. The novel LIA, evaluated with an inter-comparison measurement of ambient NO₂ at the ppbv concentration level, shows an identical performance (in terms of measurements accuracy and precision) as the widely used commercial LIA (SR830, Stanford Research Inc.), while using a simplified and lightweight hardware architecture. Evaluation of the aerosol impact on climate requires accurate and unbiased quantification of the its wavelength-dependent optical properties over a wide spectral region of the major solar radiation, which can provide information on particle size (due to the wavelength dependence of scattering by fine particles) as well as insights on aerosol chemical composition (because of its wavelength selective absorption). To date, it is still a key challenge in atmospheric science and climate change research. Development of a broadband aerosol albedometer is ongoing, which is dedicated to simultaneous measurements of aerosol extinction and absorption coefficients with high-accuracy and high-precision
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Wetherell, Emily Michelle. "The use of crowdsourcing in the development of measurement instruments." Thesis, University of Iowa, 2019. https://ir.uiowa.edu/etd/6879.
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Crowdsourcing has gained favor among many social scientists as a method for collecting data because this method is both time- and resource-efficient. The present study uses a within-subject test-retest design to evaluate the psychometric characteristics of crowdsource samples for developing and field testing measurement instruments. As evidenced by similar patterns of psychometric characteristics across time, strong test-retest reliability, and low failure rates of attention check items, the results of this study provide evidence that Amazon Mechanical Turk might represent a fruitful platform for field testing to support the development of a variety of measures. These findings, in turn, have significant implications for resource efficiency in the fields of educational and organizational measurement.
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Sharp, David Brian. "Acoustic pulse reflectometry for the measurement of musical wind instruments." Thesis, University of Edinburgh, 1996. http://hdl.handle.net/1842/14396.
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The bore profile and input impedance of a musical wind instrument provide valuable information about its acoustical properties. The time domain technique of acoustic pulse reflectometry can be used to measure the input impulse response of a tubular object, such as a wind instrument, from which both its bore profile and input impedance can be calculated. In this thesis, after a discussion of the theory of acoustic pulse reflectometry, the operation of a practical reflectometer is described and measurements of input impulse response, bore profile and input impedance are investigated. In general, the experimentally measured input impulse response of a tubular object contains a DC offset which must be removed for accurate bore reconstruction. A new, faster method of determining the DC offset is introduced which doesn’t require prior knowledge of the object’s dimensions. The bore profile of a test object, calculated by applying a lossy reconstruction algorithm to its input impulse response (after removal of the DC offset), is found to agree with directly measured radii to within 0.05mm. Various brass instrument reconstructions of similar accuracy are presented. An input impedance curve, calculated from the input impulse response of the test object, is found to have peak frequencies which agree with those of a theoretical curve to within 0.7% (a considerably better agreement than when a standard frequency domain measurement technique is used). Impedance curves of various brass instruments are presented. Bore reconstructions are used to confirm the presence, and in certain cases, the positions of leaks in instruments. For the special case of a leaking cylinder, the impedance curve is successfully used to calculate the size of the leak. Finally, a method is investigated which allows the practical reflectometer to measure longer objects than previously possible.
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Mayes, Alex. "LDA and CFD calibrations of airflow-measurement instruments in industry." Thesis, London South Bank University, 2014. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.634038.
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This study involved the use of Laser Doppler Anemometry (LDA) to measure air flows at high temporal and spatial resolution for the calibration of high-precision instrumentation, together with the use of Computational Fluid Dynamics (CFD) modelling tools. The work was performed in conjunction with BSRIA Instrument Solutions (BIS) with the main aim of improving the speed and accuracy of the calibration facilities within the BIS laboratory through the novel application of these technologies. Throughout the exploration of each facility, experimental LDA measurements, theory and virtual CFD models were compared to explore the airflow behaviour. In Part 1 of the investigation, this primarily focussed on a Balometer Calibration Facility (BCF – volume flow device) and an Open Jet Wind Tunnel (OJWT – air velocity device); both controlled using orifice plate pressure drops. The BCF was explored using attached sections of square ducting with optical access for LDA measurements. A traversing method was devised to measure volumetric flow rates, which were compared to the measured orifice plate pressure drops in order to achieve calibration of the facility. Comparing traversing methods showed that a Log-Tchebycheff method provided the most accurate prediction. The BCF calibration method was devised such that is could be applied to other volume flow facilities. These experimental measurements were compared with CFD simulations of ducted airflow in square and circular cross-section geometries for further analysis including the theoretical 1/7th power law velocity profile along with profile method comparisons. A further volume flow device, the Blower Door Calibraion Facility (BDCF) was investigated using a similar process to show the generality of the devised method. The OJWT, a facility typically used to calibrate velocity devices such as anemometers, was calibrated using a simple but novel calibration process involving LDA. To investigate further the OJWT behaviour, CFD models were created to represent OJWT with and without an anemometer and contrasted with equivalent experimental situations. A comparison of these experimental and computational data sets was performed showing representation of experimentally observed phenomena within the CFD model. This included so-called „blockage factors‟, mentioned below. iii In operation, to achieve the calibration of anemometers, the OJWT must make use of Blockage Factors (BFs) in order to correct the calibrated reference velocity to determine the actual velocity experienced by the unit under test. This was explored in Part 2 of the project. Experimental and computational (CFD) investigations were performed to explore the nature of the BFs towards a method of prediction. This would be of great use to industry as an anemometer calibration is not valid on an OJWT if an incorrect BF was applied. Outputs include: Novel methods of calibration were devised for test facilities which successfully achieved UK Accreditation Service (UKAS) certification. LDA was used to show that, in square ducts, the Log-Tchebycheff profiling method performs better than Equal Areas at providing an estimate for average cross sectional velocity when both low- and high- flow rates are considered. To verify CFD models of ducted airflow and of near-field measurements around an anemometer within an OJWT, LDA was shown to be a powerful tool. The basis for a method of BF prediction was proposed. This is based upon the empirical relationship between a statistical analysis of numerous calibrations along with an experimental LDA measurement of the deflection of air around an anemometer (Radius Expansion – RE). This is a first use within the industry and is an original contribution to knowledge. CFD models were also employed in the investigation of BFs, and the empirical relationship was applied to the data extracted from these simulations. Results closely matching the expected values were produced. The empirical relationship (between RE and BF) was demonstrated through estimation of the BF of an unknown Kimo 70 mm anemometer.
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Gow, Joel A. "Testing the HG1700 inertial measurement unit for implementation into the AIRES unmanned underwater vehicle." Thesis, Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 2005. http://library.nps.navy.mil/uhtbin/hyperion/05Jun%5FGow.pdf.
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Thesis (M.S. in Applied Science (Physical Oceanography))--Naval Postgraduate School, June 2005.Thesis Advisor(s): Anthony J. Healey, Edward B. Thornton. Includes bibliographical references (p. 49). Also available online.
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Bertan, Hilton Henrique 1979. "Analise de aplicação e desempenho de uma esfera integradora em radiometros para calibração de medidores de potencia optica." [s.n.], 2007. http://repositorio.unicamp.br/jspui/handle/REPOSIP/260064.
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Orientador: Yuzo IanoDissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Eletrica e Computação
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Resumo: Uma esfera integradora e suas propriedades foram estudadas a fim de se obter um padrão de referência em medição de potência óptica. Este trabalho apresenta pesquisas realizadas em laboratórios nacionais e internacionais. As medições com uma esfera foram comparadas com as de um medidor de potência óptica padrão de um laboratório de calibração brasileiro e com equipamentos de um laboratório de medições ópticas europeu. Os resultados indicaram que a esfera integradora em questão apresenta uma incerteza de medição menor e, portanto, pode ser usada como padrão de referência. Este trabalho também tem como finalidade mostrar que é possível elaborar um procedimento de escolha de um novo equipamento padrão utilizando-se recursos e equipamentos limitados disponíveis no laboratório
Abstract: We have studied an integrating sphere and its properties for application as a reference standard in optical power measurement. This work shows the researches made in national and international laboratories. We have compared the measurements of a sphere with the standard optical power meter of a Brazilian calibration laboratory and with equipments of a European optical measurement laboratory. The results indicate that the integrating sphere can be used as a reference standard, because its measurement uncertainty is small. This work also has the purpose to show that a procedure for the choice of new standard equipment is reliable using resources and equipment commonly available in a laboratory
Mestrado
Telecomunicações e Telemática
Mestre em Engenharia Elétrica
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Balotta, Graciano Augusto Peviani. "Análise de três métodos de estimativa da evapotranspiração de referência para a região de Pradópolis - SP /." Jaboticabal : [s.n.], 2011. http://hdl.handle.net/11449/88228.
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Orientador: José Eduardo Pitelli TurcoBanca: Adhemar Pitelli Milani
Banca: Renato Farias do Valle Júnior
Resumo: O objetivo desse trabalho foi avaliar três métodos de estimativa da evapotranspiração de referência (Hargreaves, Radiação Solar e Makkink), comparando-os com o método de Penman-Monteith, recomendado pela Organização das Nações Unidas para a Alimentação e Agricultura (FAO) como método padrão para estimativa da ETo, para o município de Pradópolis - SP. Para esse fim foi instalada no posto agrometeorológico da cidade de Pradópolis - SP uma estação meteorológica automatizada. Por intermédio desta estação foram obtidas medidas da radiação solar global, temperatura do ar, umidade relativa do ar e velocidade do vento. A análise dos resultados foi feita por uma técnica que considera os erros da ET0. O resultado da avaliação dos métodos indica um melhor ajuste para estimativa da ETo para o método de Hargreaves. Os métodos de Makkink e Radiação Solar não obtiveram um ajuste satisfatório com o do Penman-Monteith. Para avaliar métodos de estimativa da evapotranspiração deve-se considerar os erros da estimativa da ETo, evitando possíveis erros de avaliação
Abstract: The aim of this investigation was to evaluate two reference methods to Monteith method, recommended by the Food and Agricultural Organization of the United Nations (FAO) as the standard method for estimating ETo in Pradópolis - SP. To this data collection, an automated weather station was installed in the meteorological station at Pradópolis - SP. Through estimate evapotranspiration (Hargreaves, Radiation and Makkink), compared to Penman-this station, we obtained measures of global solar radiation, air temperature, relative humidity and wind speed. The analysis was done by a technique that considers the mistakes of ETo, which depends on the combination of the errors of the variables that make up the estimating equations, derived from the measurement instruments used to obtain these variables. The aftermath showed a better adjustment to Hargreaves. Makkink, and Radiation methods are different from Penman-Monteith, therefore, they cannot be compared. To evaluate methods to estimate evapotranspiration and avoid possible evaluation errors, ETo estimate errors must be considered
Mestre
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Callahan, Gary L. "The measurement of finger dexterity in woodwind and brass instrumentalists : a developmental study /." The Ohio State University, 1986. http://rave.ohiolink.edu/etdc/view?acc_num=osu1340907240.
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Chan, Y. Boris. "Air turbine handpieces : applied force measurement in dental procedures /." View the Table of Contents & Abstract, 2005. http://sunzi.lib.hku.hk/hkuto/record/B31490347.
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Chan, Y. Boris, and 陳宇. "Air turbine handpieces: applied force measurement in dental procedures." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2005. http://hub.hku.hk/bib/B45007718.
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Fletcher, Douglas Dwayne. "Adaptive filtering for extracting asymmetric rotating body information from measurement sensors." Thesis, Georgia Institute of Technology, 1994. http://hdl.handle.net/1853/15661.
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Garner, Harry Douglas Jr. "Development of a grating interferometer for non-contact relative displacement measurement." Thesis, Georgia Institute of Technology, 1998. http://hdl.handle.net/1853/17086.
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Rahimzadeh, Bizhan. "Design of a cross-correlator for process measurements." Thesis, Manchester Metropolitan University, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.254857.
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Bergstrom, Torbjorn S. "Investigation of measurement artifacts introduced by horizontal scanning surface profiling instruments." Link to electronic thesis, 2002. http://www.wpi.edu/Pubs/ETD/Available/etd-0108102-131441.
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Toledo, Bittner Felipe Ignacio. "Development of Low-Cost instruments for the measurement of atmospheric parameters." Tesis, Universidad de Chile, 2017. http://repositorio.uchile.cl/handle/2250/150618.
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Magíster en Ciencias de la Ingeniería, Mención Eléctrica. Ingeniero Civil EléctricoLas nubes y los aerosoles atmosféricos, tanto de origen natural como antropogénico, poseen una rol importante en el clima debido a su influencia sobre el forzamiento radiativo de la Tierra. Estos elementos poseen complejas interacciones entre sí, lo que ha llevado a paneles internacionales de ciencias atmosféricas a destacarlos como poseedores de incertidumbres clave para la comprensión de los cambios climáticos futuros. Una de los obstáculos que impide el tener mejor certeza en los datos es la baja disponibilidad de instrumentos meteorológicos sobre la superficie de la Tierra que permitan respaldar y complementar las mediciones satelitales. Este trabajo consiste en el desarrollo de los prototipos de un fotómetro solar y de un radar de nubes. Los prototipos están diseñados con el objetivo de mantener bajos los costos de fabricación, con el objetivo de mejorar la disponibilidad de datos para el estudio de la interacción entre aerosoles y nubes. Con el fotómetro solar desarrollado se logró obtener una incertidumbre de 10\% respecto a un instrumento patrón, alcanzando un costo accesible que permitiría el establecimiento de redes de medición a escalas pequeñas. Esto fue posible debido a la utilización de LEDs como sensores monocromáticos de luz visible no ideales (100 [nm] de ancho), y por la inclusión de nuevas consideraciones en la calibración y procesamiento de datos del instrumento. Además, se logra construir una prueba de concepto de radar de nubes de 35 [GHz]. Dicho radar mantuvo su bajo costo en base a la reutilización de componentes de radio telescopio y el uso de radios definidas por software en vez de circuitos de modulación integrados. Con este prototipo se obtuvo una constante de calibración tentativa de $\pm 1$ [dBZ] de incertidumbre , y se realizó un experimento en el que se verifica que existe interacción entre su señal y la presencia de gotas de agua líquida en suspensión. Finalmente, la conclusión incluye sugerencias sobre la forma de abordar proyectos de instrumentación atmosférica de bajo costo, basadas en la experiencia del autor.
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He, Zaiqian. "Investigation of a multi-purpose optical measurement system /." View abstract or full-text, 2005. http://library.ust.hk/cgi/db/thesis.pl?IEEM%202005%20HE.
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Bhuiya, Md Omar Faruqe. "Design and optimization of a stripline resonator sensor for measurement of rubber thickness." Akron, OH : University of Akron, 2006. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=akron1164650416.
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Thesis (M.S.)--University of Akron, Dept. of Electrical Engineering, 2006."December, 2006." Title from electronic thesis title page (viewed 10/17/2007) Advisor, Nathan Ida; Committee members, James Grover, George C. Giakos; Department Chair, J. Alexis De Abreu Garcia; Dean of the College, George K. Haritos; Dean of the Graduate School, George R. Newkome. Includes bibliographical references.
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Sundström, Anna. "Developing and validating self-report instruments : assessing perceived driver competence." Doctoral thesis, Umeå universitet, Beteendevetenskapliga mätningar, 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-26764.
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The overall aim of this thesis was to develop and validate a self-report instrument for perceived driver competence. The thesis includes six papers and a summary. All papers focus on perceived driver competence from a measurement perspective; that is, how to develop an instrument for perceived driver competence and how to use and interpret the scores from the instrument in a reliable and valid manner. Study I reviews how perceived driver competence has been measured in other studies and discusses these methods from a measurement perspective. Most studies have examined perceived driver competence by asking drivers to compare their own skill to that of the average driver. That method is problematic, since it is not possible to determine if drivers are overconfident or not, when empirical information of their own skills is missing. In order to examine if drivers overestimate their skills or not, perceived driver competence should be compared with actual driving performance. Study II reports on the development and psychometric evaluation of a self-report instrument for perceived driver competence - the Self-Efficacy Scale for Driver Competence (SSDC). The findings provides support for construct validity, as the SSDC demonstrated sound psychometric properties and as the internal structure of the SSDC corresponded to the theoretical model used as a basis for instrument development. In study III, the psychometric properties of the SSDC were further examined using an item response theory (IRT) model. The findings confirmed the results indicated by the classical analyses in Study II. Additional information was provided by the IRT analyses, as it was indicated that the scale would benefit from fewer scale points or by putting labels on each scale point. In study IV, Swedish and Finnish candidates’ self-assessment accuracy was examined by comparing candidates’ scores on the SSDC and a similar instrument for self-assessment of driving skill used in Finland, with driving test performance. Unlike previous studies, in which drivers compared their perceived skills to that of the average driver, a relatively large proportion made a realistic assessment of their own skills. In addition, in contrast to previous studies, no gender differences were found. These results were also confirmed in study V, where the results from the Finnish instrument for self-assessment of driving skill were compared with the results from a similar instrument used in the Netherlands. Study VI further examined the construct validity of a revised version of the SSDC, combining qualitative and quantitative sources of evidence. There was a strong relationship between the SSDC and an instrument for self-assessment of driving skills, providing support for convergent validity. No relationship was found between the SSDC and driving test performance. Explanations of the lack of relationship were provided from semi-structured interviews, as they indicated that confidence in performing different tasks in the test are different from being confident of passing the test, and that the candidates are familiar neither with assessing their own skills nor with the requirements for passing the test. In conclusion, the results from this thesis indicated that the choice of methods for assessing perceived driver competence as well as the quality of these methods affect the validity. The results provided support for different aspects of construct validity of the SSDC. Moreover, the findings illustrated the benefits of combining different methods in test validation, as each method contributed information about the validity of the SSDC. The studies in this thesis mainly examined internal and external aspects of construct validity. Future studies should examine procedural validity of the SSDC.
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Meade, Roy Edward. "Quantitative measurement of surface wear via a non-vibrating kelvin probe." Thesis, Georgia Institute of Technology, 1996. http://hdl.handle.net/1853/15999.
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Allan, James Donald Campbell. "An application of optical interference to dynamic position measurement in three dimensions." Thesis, University of Edinburgh, 1988. http://hdl.handle.net/1842/6627.
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This thesis is concerned with the measurement of the positions of points and bodies moving in trajectories in three dimensions, and the use of a new technique of optical interference which allows such measurements to be made dynamically. A variety of existing techniques for both static and dynamic three-dimensional position measurement are discussed, and the design of the new interferometer is introduced. The geometry of points, curves and surfaces in three dimensions is examined, with emphasis on the intersection of the point loci represented by the coordinate output of measuring instruments. The coordinates output by the interferometer represent surface loci which are quadric surfaces. A method of calculating the position and orientation of a body using three quadric surface intersection curves is presented. Diffraction of monochromatic light at an aperture is considered and it is shown that an interferometer working by division of wavefront can be used to obtain continuous information about the movement of the source of radiation, with that source free to move in up to three dimensions. A lens may be used to produce a compact instrument based on these principles. The diffraction integral equations are modified to incorporate the effect of a lens in the diffraction field. It is shown that even complex lenses can be represented by a few parameters in the diffraction equations. From the evaluation of these diffraction integrals, it is shown how the movement of interference fringes provides a coordinate output and how this is related to the locus of the radiation source. A method of obtaining very high resolution measurements of interference fringe pattern movement is presented. The interferometer was built and tested and the above theory verified in practice in a series of optical bench tests. The implementation of a system which uses this interferometer to measure the dynamic performance of industrial robots is considered. The optimum positions for the instruments are derived, and the method of designing the interferometer to give the required resolution is presented.
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Hosch, India A. "Parental perception of effectiveness of Q-sort methodology in measuring attachment in children with atypical behaviors." Diss., This resource online, 1995. http://scholar.lib.vt.edu/theses/available/etd-06062008-160422/.
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Houser, Scott A. "Medial surface transformations for rapid approximation of casting solidification." Thesis, Virginia Tech, 1996. http://hdl.handle.net/10919/45089.
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This thesis demonstrates the feasibility of using a medial surface transformation as a tool
to rapidly approximate the solidification patterns of convex faceted solid models of
castings. The medial surface transformation is used to automate the greatest included
sphere approach to solidification pattern approximation. The experimental software of
this thesis extracts the medial surface transformation from a convex faceted model by
computing the model's Voronoi diagram and uses it to identify casting hot spots and
cooling patterns. Comparison with a finite difference method (FDM) solution showed that
the locations and shapes of hot spots predicted by FDM converge to the shapes and
locations predicted by the experimental software.
Master of Science
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Strachan, Heather. "Person-centred caring : its conceptualisation and measurement through three instruments (personalisation, participation and responsiveness)." Thesis, Glasgow Caledonian University, 2016. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.726770.
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Weyers, Anna M. "Comparison of body composition using the Bod Pod and dual-energy x-ray absorptiometry before and after weight loss." Virtual Press, 2000. http://liblink.bsu.edu/uhtbin/catkey/1164840.
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No research has been performed comparing percent body fat measurements using dual energy x-ray absorptiometry (DEXA) and air plethysmography after weight loss. The purpose of this investigation was to compare body composition assessments using the Bod Pod® Body Composition System (BP) and the DEXA ProdigyTM before and after an 8-week weight loss diet and exercise program. Based on prior comparison studies, it was hypothesized that percent fat values would be significantly lower using the BP compared to the DEXA before and after weight loss. Also since both methods have been shown to be reliable, it was hypothesized that the BP and DEXA would detect similar changes in percent fat in response to a weight-loss intervention. Twelve women (42 ± 8 yrs) and ten men (40 + 11 yrs) had their percent body fat estimated using the BP and whole body DEXA ProdigyTM scanner. A similar significant (P < 0.05) decrease in percent body fat was observed using the BP and DEXA ProdigyTM (-2.2% and -1.8%, respectively) after weight loss. Percent body fat using the BP was significantly lower than the DEXA ProdigyTM before (36 ± 10.7% and 38.1 ± 9.4%, respectively) and after (33.8 ± 10.8% and 36.3 + 10.6%, respectively) the weight loss program. Significant Pearson correlation coefficients between the DEXA ProdigyTM and the BP were noted pre (r = 0.975) and post (r = 0.968) weight loss. These data indicate the BP provides significantly lower absolute %fat values within a range of body fat levels (20-56%) when compared to the DEXA. However, the BP and DEXA detect similar changes in %fat, fatfree mass, and fat mass from weight loss in men and women. Also, the BP consistently overestimated fat-free mass and underestimated %fat and fat mass compared to values obtained from DEXA.School of Physical Education
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Wolfaardt, H. Jurgens. "Theory of the microfluidic channel angular accelerometer for inertial measurement applications." Pretoria : [s.n.], 2005. http://upetd.up.ac.za/thesis/available/etd-05152007-120803.
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Bručas, Domantas. "Development and research of the test bench for the angle calibration of geodetic instruments." Doctoral thesis, Lithuanian Academic Libraries Network (LABT), 2008. http://vddb.library.lt/obj/LT-eLABa-0001:E.02~2008~D_20080620_092300-91259.
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The main idea of current PhD thesis is an accuracy analysis of testing and calibration of geodetic instruments. The object of investigation is an analysis of means and methods for testing and calibration of geodetic instruments for plane angle measurement, development of such calibration equipment, its accuracy investigation and the research of its accuracy increasing possibilities. These objects are important for successful testing or calibration of geodetic instruments for angle measuring which is essential in ensuring the precision of measurements taken in surveying, construction, mechanical engineering, etc.
There are several main goals of the presented work. First one is an analysis of the angle measuring methods and devices suitable for the testing and calibration of geodetic instruments, according to the results of the mentioned analysis the second task can be formulated – creation of a multi-reference plane angle testing and calibration equipment at Institute of Geodesy, Vilnius Gediminas Technical University and investigate the parameters of its accuracy. The third task is to investigate the accuracy increasing possibilities of the equipment, and implementation some of them into the practice.
The thesis consists of four chapters, introduction, conclusions, list of references and appendixes.
Introduction is dedicated for an introduction to the problem and its topicality. There are also formulated purposes and tasks of the work; the used methods and novelty of... [to full text]Disertacijoje nagrinėjamos geodezinių kampus matuojančių prietaisų patikros bei kalibravimo metodai bei priemonės. Pagrindinis tyrimo objektas yra geodezinių prietaisų tikslumo parametrų matavimo būdų ir priemonių analizė, kalibravimo įrenginio kūrimas, jo tikslumo charakteristikų tyrimas bei įrenginio tobulinimas. Šie objektai yra svarbūs vykdant geodezinių prietaisų kalibravimą, kas savo ruožtu yra labai svarbu užtikrinant reikiamą šių prietaisų matavimų tikslumą geodezijoje, statybose, mašinų gamyboje ir t. t. Pagrindinis disertacijos tikslas – geodezinių kampų matavimo prietaisų kalibravimo galimybių analizė ir sukurto kalibravimo įrenginio tikslumo para¬metrų tyrimas. Darbe sprendžiami keli pagrindiniai uždaviniai: plokščiųjų kampų mata¬vimo metodų bei įrenginių, tinkamų geodeziniams prietaisams kalibruoti, analizė; daugiaetalonio kampų kalibravimo stendo kūrimas Vilniaus Gedimino technikos universiteto Geodezijos institute bei jo tikslumo charakteristikų tyri¬mas; stendo tikslumo didinimo galimybių bei priemonių tyrimas, ir apskri¬timinių skalių kalibravimo būdų tobulinimas. Disertaciją sudaro šeši skyriai, įvadas, išvados, literatūros sąrašas bei priedai. Įvade nagrinėjamas problemos aktualumas, formuluojamas darbo tikslas bei uždaviniai, aprašomas mokslinis darbo naujumas, pristatomi autoriaus pranešimai ir publikacijos, disertacijos struktūra. Pirmasis skyrius skirtas labiausiai paplitusių plokščiųjų kampų matavimo būdų bei priemonių tinkamų geodeziniams prietaisams... [toliau žr. visą tekstą]
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Kelly, Harold Lorain Jr 1958. "Remote measurement of turf water stress and turf biomass." Thesis, The University of Arizona, 1989. http://hdl.handle.net/10150/276995.
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Increasing irrigation efficiency on turfgrass could help reduce water consumption on large turf facilities. Two experiments were conducted using perennial ryegrass (Lolium perenne (L.) Derby) to evaluate the potential of using remote sensing to estimate turf water status, predict daily evapotranspiration (ET), and estimate turf biomass. In the first experiment a crop water stress index, utilizing remotely sensed canopy temperature, were used to schedule irrigations on 6 of 10 drainage lysimeters. Three of the remaining lysimeters were irrigated used on meteorological estimates of ET calculated using a modified Penman equation. The results of this experiment were inconclusive due to inconsistent lysimeter drainage characteristics. The second experiment was conducted on a turf green with multiple heights to evaluate the potential for using canopy radiance to estimate turf biomass. These results showed that turf biomass could be estimated from a vegetative index (Red Ratio = Near Infrared/Red radiance) obtained through measurements of canopy radiance (r2 = 0.91).
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Chen, Chang. "A voice controlled measurement procedure for the high energy physics laboratory." Virtual Press, 1990. http://liblink.bsu.edu/uhtbin/catkey/770952.
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A Zenith-386 workstation was outfitted with a DICRES-54.8 paralell port board to facilitate I/C between a large Summagrid x-y coordinate digital measurement pad that has a resolution of 10 microns. Film views of high energy particle collisions can be projected onto this pad for measurement. Voice prompts via a Votrax speech synthesis system are sent at critical points during the algorithm from the Z-386 through other ports of the DICRES board. Progress in measurement is fed into the Z-386's serial port from an Interstate voice recognition system at other points of the measurement algorithm. The whole measurement process is managed by an assembler language based modular computer program.Department of Physics and Astronomy
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Hardy, Christopher R. "An examination of the dimensionalities and common constructs of selected adult cognitive learning style instruments." Diss., This resource online, 1995. http://scholar.lib.vt.edu/theses/available/etd-09192008-063044/.
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Zushi, Takahiro. "Study on Miniaturization of Plasma Wave Measurement Systems." Kyoto University, 2019. http://hdl.handle.net/2433/242507.
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Osorno, Daniel. "Rolling element skew measurement in a spherical roller bearing utilizing a CPD probe." Thesis, Available online, Georgia Institute of Technology, 2005, 2005. http://etd.gatech.edu/theses/available/etd-08242005-140539/.
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Thesis (M. S.)--Mechanical Engineering, Georgia Institute of Technology, 2006.Steven Danyluk, Committee Chair ; David Sanborn, Committee Member ; Shreyes Melkote, Committee Member. Includes bibliographical references.
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Þórisdóttir, Jóhanna G. "Follow-up interventions and measurement instruments for patients suffering from psychotic disorder : A literature review." Thesis, Nordic School of Public Health NHV, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:norden:org:diva-3442.
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Background: Continuity of care and post-discharge follow-up visits can improve the quality of care and reduce the likelihood of relapse and re-hospitalization in patients with psychotic disorders. Purpose: This study aimed to analyze post-discharge follow-up interventions in patients with psychotic disorders, and to identify measurement instruments for intervention outcomes. Method: The literature review described here used a specific framework, where the follow-up interventions and the measurement instruments were analyzed systematically, to investigate fifteen studies identified through electronic databases such as Pubmed, Psychinfo, ProQuest, Cinahl, Medline, and Scopus. Results: The studies used interventions including psychoeducation, cognitive-behavioral therapy, cognitive behaviorally oriented service, optimal clinical management, relapse prevention plan, software suggested intervention, ambulatory outpatient care, community re-entry module, integrated treatment, and hospital-based community psychiatric service. Additionally these studies used thirty-eight measurement instruments to assess change in psychiatric patients or their relatives, based on psychological, social, and occupational factors as well as specific symptoms and symptom severity. The instruments also measured quality of life, insight, self-esteem, and cognitive function. Further, the studies examined therapeutic alliances and the experience of family members. The most commonly used instruments were the Global Assessment of Functioning and the Positive and Negative Syndrome Scale. Conclusion: The interventions reviewed here emphasize an individualized approach that targets education, illness management, coping strategies, social skills training and relapse prevention, and seeks to alter any harmful understanding of the illness. Although researchers can choose among numerous interventions, psychoeducation was the most appealing follow-up intervention for patients suffering from psychotic disorders. Importantly, evaluation instruments must be relevant to psychological symptoms, treatment, time and resources available, and what questions were being sought to answer. Approximately eleven of the thirty-eight instruments reviewed here showed weak or unclear reliability and validity. The most practical instrument for evaluating the outcome of an intervention for patients suffering from psychotic disorders wasthe Positive and Negative Syndrome Scale.ISBN 978-91-86739-70-6
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Bodon, K. Joshua. "Development, Evaluation, and Validation of a High-Resolution Directivity Measurement System for Played Musical Instruments." BYU ScholarsArchive, 2016. https://scholarsarchive.byu.edu/etd/5653.
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A high-resolution directivity measurement system at Brigham Young University has been renovated and upgraded. Acoustical treatments have been installed on the microphone array, professional-grade audio hardware and cabling have been utilized, and user-friendly MATLAB processing and plotting codes have been developed. The directivities of 16 played musical instruments and several loudspeakers have been measured by the system, processed, and plotted. Using loudspeakers as simulated musicians, a comprehensive analysis was completed to validate the system and understand its error bounds. A comparison and evaluation of repeated-capture to single-capture spherical systems was made to demonstrate the high level of detail provided by the 5 degree resolution system. Analysis is undertaken to determine how nonanechoic effects in anechoic chambers influence results. An overview of directivity measurement systems from the literature is provided as well as a dedicated discussion of the directivity measurement system at Brigham Young University.
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Ma, Bin-Bing. "Passive acoustic detection and measurement of rainfall at sea and an empirical ocean ambient sound model /." Thesis, Connect to this title online; UW restricted, 2004. http://hdl.handle.net/1773/11045.
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De, Vries Marten J. "Simultaneous measurement of strain and temperature using liquid core optical fiber sensors." Thesis, This resource online, 1993. http://scholar.lib.vt.edu/theses/available/etd-03042009-040438/.
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Hebbard, Geoffrey Stuart. "Proximal gastric motor and sensory function in health and disease /." Title page, contents and summary only, 1997. http://web4.library.adelaide.edu.au/theses/09PH/09phh443.pdf.
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McCarty, Matthew Aerospace Civil & Mechanical Engineering Australian Defence Force Academy UNSW. "The measurement of the pressure distribution over the wing of an aircraft in flight." Awarded by:University of New South Wales - Australian Defence Force Academy, 2008. http://handle.unsw.edu.au/1959.4/39002.
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A measurement system has been developed for use on a light aircraft to measure the pressure distribution over the wing surfaces. The measurement system was developed as a low-cost alternative to existing advanced measurement systems. The system consisted of low profile, low cost pressure sensors that interfaced digitally with microcontrollers for data acquisition. The pressure sensors and microcontrollers were developed into self-contained sensor modules with all electronic components mounted on flexible circuit board that formed the base of the modules. Two types of module were developed; a module with a single pressure sensor and a module with a row of seven pressure sensors at fifteen millimetre spacing. The total cost of the sensor modules was approximately ninety dollars for a single sensor module and one hundred and forty dollars for the seven sensor module. Studies were carried out using numerical methods to predict the pressure distribution over a NACA2412 airfoil. The numerical studies were used to evaluate the effect of adding the sensor modules to the wing, and the effect of the sensor distribution on measured force coefficients. Numerical predictions were made using the XFOIL software package. This software was validated using the Hess-Smith inviscid panel method. Flight testing was carried out with the pressure distribution measurement system to confirm the operation of the system and to make preliminary measurements. The flight testing focused on the measurement of steady state pressure distributions for comparison with the numerical predictions. Good agreement was found between the measured pressure distributions and the XFOIL predictions. Integration of the pressure distributions enabled comparison of normal force, lift force and quarter chord moment coefficients. The measured force coefficients showed the expected trends with angle of attack although it was found that the limited number of sensor modules used caused large error in the quarter chord moment coefficient compared to the numerical predictions.
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Khanyile, Bhekumuzi Sfundo. "An investigation of the atmospheric wave dynamics in the polar region using ground based instruments." Thesis, University of Fort Hare, 2011. http://hdl.handle.net/10353/447.
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Abstract This study presents the characteristics of small-scale gravity waves in the mesosphere region as derived from the imaging riometer data at high altitude (~90 km) over SANAE (72˚S, 3˚W). Wavelet analysis and FFT (Fast Fourier transform) have been applied to extract short period gravity wave parameters for the year 2000. The horizontal wavelength, phase speed and observed period of gravity waves are typically 10-100 km, 5-60 m.s-1 and 3-60 minutes, respectively. The horizontal propagation direction is north-eastward throughout the year. This could probably be due to selective filtering by the zonal wind. Zonal and meridional winds in the region of the MLT (mesosphere and lower thermosphere) have been measured using HF radars at high latitudes in the southern hemisphere. Data from January 2000 to December 2003 have been used with the aim of investigating the characteristics of planetary wave activity at ~90 km. For SANAE and Halley stations, 2-, 5-, 10-, 16- and 20-day planetary waves are dominant in summer and winter. The results show the seasonal variations of the mean winds, which are caused by the internal variability of the quasi stationary planetary waves. Planetary wave coupling processes between UKMO assimilated and mesospheric data have also been investigated. The cross wavelet results show a strong coupling during winter months. The results suggest that planetary waves are generated at lower atmospheric heights and propagate upwards into mesospheric heights. However, not all observed disturbances in mesospheric heights can be explained by the propagation of planetary waves from lower atmospheric heights.
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Borg, Daniel, and Ulf Mantling. "Syntetiska Instrument." Thesis, University of Gävle, Ämnesavdelningen för elektronik, 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:hig:diva-5481.
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This thesis aims to investigate SAAB AB´s possibilities to use synthetic instruments in their test systems. The reason for this is reducing costs and the risk of obsolescence which is common when test systems operate for several decades.
The market around synthetic instruments has been explored in the search for suitable hardware and software. Software has been developed in LabVIEW and synthetic instruments have been created with the help of IVI-drivers. The hardware consisted of PXI-instruments (Waveform generator and Digitizer), connected to a computer using a fiber optic link and PXI-chassi. The created instruments was then compared to common instruments used today, and the comparison turned out well. Advantages, disadvantages and the theory surrounding synthetic instruments is also covered. This thesis is only an introduction and further work will be necessary to implement synthetic instruments at SAAB.
The thesis also purposes suitable hardware and further development based on the test systems used today, and how it is possible to solve the layer structure.
Detta examensarbete har som mål att undersöka möjligheterna för SAAB AB att börja använda sig av syntetiska mätinstrument i sina testsystem. Anledningen till detta är att SAAB AB vill minska kostnaderna och riskerna för obsolescens som finns när testsystem är i drift i flera decennier. Detta har inneburit att marknaden har sonderats efter lämplig hårdvara och mjukvara för tillämpningen. Förutom detta har mjukvara tagits fram i LabVIEW och syntetiska instrument skapats med hjälp av IVI-drivrutiner. Som hårdvara användes PXI-instrument (vågformsgenerator och digitizer) med tillhörande chassi och fiberoptisk länk från National Instruments. De framtagna instrumenten har jämförts med vanliga reella instrument och visat sig fungera väl, men även fördelar och nackdelar belyses samt teori kring hur syntetiska instrument fungerar. Examensarbetet är endast en introduktion i ämnet och kräver ytterligare arbete innan det är praktiskt genomförbart. Förutom detta ges även förslag på lämplig hårdvara och vidareutveckling baserat på hur testsystemen ser ut i dag, och förslag på hur lageruppbyggnaden skulle kunna lösas.
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Souza, Matheus Oliveira. "Sensor de nível tipo deslocador com autocompensação da densidade do líquido." Pós-Graduação em Engenharia Elétrica, 2018. http://ri.ufs.br/jspui/handle/riufs/9568.
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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPESLevel measurement plays a crucial role in a wide range of scientific and industrial applications, such as agriculture, hydrology, soil science, oil, pharmaceutical and food industries, among others. Due to the need of measuring level in different environments and for different liquids, granulated solids or powder, several sensors have been proposed to this end, for example, capacitive, infrared, hydrostatic, ultrasonic, radar, laser, optical, displacer, among others, each having its pros and cons. In particular, displacer-type level sensors are highly linear, precise and exact for a given working condition, in addition to having low cost and being easily installed. However, these sensors estimate liquid level indirectly by measuring the buoyancy forces on a displacer connected to a strain gauge, which makes it highly sensitive to variations in liquid density. As a consequence, it is also sensitive to variations in the liquid temperature, since the density is sensitive to temperature. This makes displacer level sensors unfeasible in industrial applications that do not keep such quantities in a range tight enough to ensure low measurement errors (e.g., oil, food and pharmaceutical industries). As a way to allow for the use of displacer-type level sensors in industrial applications, it is proposed in this work and it was also built a new displacer-type liquid level sensor self-compensating for liquid density. The proposed method uses the ratio between the buoyancy forces measured by two displacers and two load cells to make it density independent and, as a consequence, temperature invariant. Such characteristic is observed in the simulations results. The prototype experimental results show that the system has high linearity, it is able to mitigate the sensitivity to the density of the measurand, and it has potential to make precise measurements.
A medição de nível desempenha um papel crucial em várias aplicações industriais e científicas, tais como produção e refino do petróleo, agricultura, hidrologia, ciências do solo, indústrias alimentícias, indústrias farmacêuticas, dentre outras. Devido à necessidade de mensurar nível em ambientes distintos e para diferentes líquidos, sólidos granulados ou pó, vários sensores de nível têm sido desenvolvidos, por exemplo, o sensor capacitivo, infravermelho, hidrostático, ultrassônico, radar, laser, óptico, deslocador, dentre outros. Cada um com suas vantagens e desvantagens. Em particular, o sensor de nível tipo deslocador tem alta linearidade, precisão e exatidão, além de ser uma tecnologia de baixo custo e instalação simples. Entretanto, esse tipo de sensor estima o nível indiretamente medindo a força empuxo em um deslocador conectado a uma célula de carga, o que o torna muito sensível a variações na densidade do líquido. Como consequência, o mesmo também é sensível a variações na temperatura do líquido, pois a densidade é sensível à temperatura. Isso inviabiliza a aplicação dessa tecnologia em atividades que a densidade ou a temperatura do líquido não é mantida em uma faixa pequena de variação, como nas indústrias farmacêuticas, alimentícias e petrolíferas. Para viabilizar a aplicação do sensor de nível tipo deslocador em tais atividades, neste trabalho é proposto e construído um sensor de nível tipo deslocador com autocompensação da densidade do líquido. O método proposto usa a relação entre as forças de empuxo medidas por dois deslocadores e duas células de carga para tornar o sensor idealmente insensível às variações na densidade do líquido e, como consequência, insensível a variações na temperatura do líquido. Tal característica é observada nos resultados por simulação. Os resultados dos experimentos realizados com o protótipo mostram que o sistema tem alta linearidade, é capaz de mitigar a sensibilidade à densidade do líquido e tem potencial para fazer medições precisas.
São Cristóvão, SE
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Ellis, Kim S. "Comparative analysis of four measurement instruments for clarinet mouthpieces and an investigation of dimensional consistency of intermediate mouthpieces /." The Ohio State University, 1991. http://rave.ohiolink.edu/etdc/view?acc_num=osu1487687959965705.
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Wang, Xuzhu. "Beam-folding ultraviolet-visible Fourier transform spectrometry and underwater cytometry for in situ measurement of marine phytoplankton." HKBU Institutional Repository, 2007. http://repository.hkbu.edu.hk/etd_ra/814.
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Boussaid-Rezkallah, Kahina. "Les instruments de mesure (poids, capacité, temps) dans l'Algérie romaine." Thesis, Paris 1, 2017. http://www.theses.fr/2017PA01H094.
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Cette étude est un travail de recherche, d'inventaire, d'analyse (archéologique, épigraphique, métrologique, technique et artistique) et d'une nouvelle approche méthodologique sur des différents témoignages archéologiques et épigraphiques relatifs à la mesure du poids, capacité et temps en Algérie romaine. Cette étude est un nouveau thème qui mérite beaucoup d'attention et qui représente beaucoup d'intérêt pour l'archéologie algérienne en particulier et de l'Afrique romaine en générale et qui contribuera à l'enrichissement de la bibliographie spécialisée dans ce domaine. Notre objectif principale, c'est de réaliser un inventaire systématique des instruments de mesures (poids, balances, pesons, crochets et plateaux de balance, ponderarium, mensa ponderaria, cadrans solaires) en notant les spécificités de chaque élément ainsi que l'état de conservation et le lieu de son emplacement actuel. L'étude de l'ensemble de ces objets, malgré leur état de dégradation pour certains et la disparition d'autres, les résultats obtenus sont tout de même importants et prometteurs : ils contribuent à éclaircir l'histoire des cités romaines en Algérie dans les domaines de l'économie, du commerce, de la technique et de l'organisation de la vie publique; ils témoignent néanmoins l'intégration de ces instruments dans la société et attester d'une connaissance de la multiplicité typologique, et les différentes caractéristiques d'utilisation. La plupart sont inédits et non répertories, certain sont rares (les deux cadrans solaires du type plan vertical dièdre de Djemila et le ponderarium du marché de cosinius) et d'autre hors normes (les deux cadrans plan horizontaux monumentaux de Timgad et de Lambèse). Ils sont considérés comme une valeur ajoutée ajoutant du crédit à nos propos et éclairant d'une façon exhaustive notre étude et qui ouvrer des nouvelles perspectivesThis study is a research, inventory, analysis (archaeological, epigraphic, metrological, technical and artistic) and a new methodological approach on various archaeological and epigraphic testimonies relating to the measurement of weight, capacity and time In Roman Algeria. Tis study is a new topic which deserves much attention and which represents a lot of interest for Algerian archeology in particular and of Roman Africa in general and which will contribute to the enrichment of the specialized bibliography in this field. Our main objective is to carry out a systematic inventory of weighing instruments (weights, scales, weighers, hooks and balance trays, ponderarium, mensa ponderaria, sundials), noting the specificities of each element and the state of Conservation and location of its current location. The study of all these objects, despite their state of degradation for some and the disappearance of others, the results obtained are still important and promising: they contribute to clarify the history of the Roman cities in Algeria in the Economy, trade, technology and the organization of public life; They nevertheless testify to the integration of these instruments into society and attest to a knowledge of the typological multiplicity, and the different characteristics of use. Most of them are unpublished and not repertory, some are rare (the two sundials of the type vertical plane dihedron of Djemila and the ponderarium of the cosinius market) and other out of norms (the two monumental horizontal planes of Timgad and Lambèse). They are seen as an added value adding credit to our remarks and enlightening our study in a comprehensive way and opening up new perspectives
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Theissen, Nikolas Alexander. "Physics-based modelling and measurement of advanced manufacturing machinery’s positioning accuracy : Machine tools, industrial manipulators and their positioning accuracy." Licentiate thesis, KTH, Skolan för industriell teknik och management (ITM), 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-263700.
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Advanced manufacturing machinery is a corner stone of essential industries of technologicallydeveloped societies. Their accuracy permits the production of complexproducts according to tight geometric dimensions and tolerances for high efficiency,interchangeability and sustainability. The accuracy of advanced manufacturingmachinery can be quantified by the performance measure of positioning accuracy.Positioning accuracy measures the closeness between a commanded and an attainedposition on a machine tool or industrial manipulator, and it is ruled by lawsof physics in classical mechanics and thermodynamics. These laws can be applied tomodel how much the machinery deflects due to gravity, expands due to a change intemperature and how much and how long it vibrates due to process forces; hence,one can quantify how much the accuracy decreases. Thus, to produce machinerywith ever higher accuracy and precision one can design machines which deflect,expand and vibrate less or one can understand and model the actual behaviour ofthe machinery to compensate for it.This licentiate thesis uses physics-based modelling to quantify the positioningaccuracy of machine tools and industrial robots. The work investigates the potentialincrease in positioning accuracy because of the simultaneous modelling of the kinematics,static deflections, vibrations and thermo-elasticity as a lumped-parametermodel of the machinery. Consequently the models can be used to quantify thechange of the accuracy throughout the workspace.The lumped parameter models presented in this work require empirical modelcalibration and validation. The success of both, calibration and validation, dependson the availability of the right measurement instruments, as these need to be ableto capture the actual positioning accuracy of machinery. This thesis focuses on theimportance of measurement instruments in industry and metrology and creates acatalogue of requirements and trends to identify the features of the measurementinstruments required for the factories of the future. These novel measurement instrumentsshall be able to improve model calibration and validation for an improvedoverall equipment effectiveness, improved product quality, reduced costs, improvedsafety and sustainability as a result of physics-based modelling and measurementof advanced manufacturing machinery.
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Ávila, Paulo Urbano. "Desenvolvimento de equipamento de simulação e calibração para aplicações automotivas embarcadas." [s.n.], 2012. http://repositorio.unicamp.br/jspui/handle/REPOSIP/260238.
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Orientador: José Antonio Siqueira DiasDissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Elétrica e de Computação.
Made available in DSpace on 2018-08-20T01:07:20Z (GMT). No. of bitstreams: 1 Avila_PauloUrbano_M.pdf: 12384470 bytes, checksum: df7ef08ecb3c0ab8dd1f62cc247aeb0a (MD5) Previous issue date: 2012
Resumo: Apresenta-se a aplicação do projeto metodológico no desenvolvimento de uma maleta para calibração e simulação de sensores em campo (SimuCal®). Este produto passou por todas as etapas do projeto de um produto novo: desenvolvimento, planejamento e aplicação, projeto conceitual e, finalmente, projeto do produto. A metodologia de projeto axiomático foi utilizada para guiar os projetistas pelas distintas fases mencionadas. O sistema foi desenvolvido visando aplicação na área de motores da indústria automotiva. Baseado nas observações coletadas por usuários que testaram o sistema, conclui-se que ele apresenta boa aceitação pelo público-alvo, além de ter custos inferiores aos produtos similares. Para automatizar o processo de medidas, utiliza-se uma placa de condicionamento (PADSi®) para termopar (tipo K) e um transdutor de pressão relativa (Motorola®). Um canal direto do micro controlador recebe e trata o sinal de frequência. O micro-controlador utilizado foi um MSP430 G2231 programado em linguagem C. Os valores recebidos pelo micro-controlador são convertidos, utilizando o módulo de Conversão Analógica Digital (ADC) do microcontrolador, tratados e enviados para o PC através da comunicação serial UART. A conversão AD do sinal é realizada pelo módulo de Conversão AD do microcontrolador da TEXAS MSP 430, com processador RISC de 16 bits. Para o computador, foi desenvolvido um programa usando LabVIEW® ® para: Aquisição dos Dados (via USB), Interface com Usuário (GUI) e Armazenamento de Dados (Datalogger). LabVIEW® é uma linguagem de programação gráfica da empresa National Instruments, com recursos que permitem a criação de interfaces gráficas para usuário (GUI), bem como entrada, saída e armazenamento de dados. O MSP430 G2231 é um micro-controlador com arquitetura Reduced Instructions Set Computing (RISC) com uma arquitetura de barramento clássica Von Neumann (Memória de programa igual à memória de dados). Seus barramentos de Endereço e Dados são de 16 bits
Abstract: An application of a methodological project in the development of a briefcase for calibration and simulation of Field sensors (SimuCal®) is presented. This product underwent of phases of a new product design: development, planning and application, conceptual design and, finally, product design. The axiomatic project design has been used to guide the involved professionals in the various mentioned phases. The system has been developed to be used in the engine area of automotive industry. Based in the collected observations of users who have tested the system, one can conclude that it is well accepted by the target market, having also lower costs than similar products. To automate the measurement process, a conditioning (PADSi®) thermocouple plate (K type) and a relative pressure transduction (Motorola®) are used. A micro-controller direct channel acquires and treats the frequency signal. The micro-controller used was a MSP430 G2231 written in C language. The values received by the micro-controller are converted, using the micro-controller Analog to Digital Conversion module, being then treated and sent to the PC by means of a serial port UART. The AD signal conversion is performed by the TEXAS MSP 430 micro-controller module, with a 16 bits RISC processor. To use in the computer, a software using LabVIEW® was developed for: Data Acquisition (via USB), Graphical User Interface and Data Storage (Datalogger). LabVIEW® is a language for graphical programming developed by National Instruments, with resources for creating Graphical User Interfaces, as well as input, output and storage of data. MSP430 G2231 is a micro-controller using RISC (Reduced Instructions Set Computing) architecture and the classical Von Neumann (program memory equal to data memory) bus architecture. Its addresses and data buses are 16 bits ones
Mestrado
Eletrônica, Microeletrônica e Optoeletrônica
Mestre em Engenharia Elétrica
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Straub, Larry G. "Promethean Framework and Measurement Instrument: Career Development, Maintenance and Transitions in Convulsive Economic Cycles." Case Western Reserve University Doctor of Management / OhioLINK, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=casedm1568628001000544.
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Liu, Jie. "Characterization of New Rotary Endodontic Instruments Fabricated from Special Thermomechanically Processed NiTi Wire." The Ohio State University, 2009. http://rave.ohiolink.edu/etdc/view?acc_num=osu1244643081.
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Westlund, Johan. "Design and construction of a contactless excitation and response measurement system." Thesis, KTH, Industriell produktion, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-246324.
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Manufacturing industry works on Overall Equipment Effectiveness (OEE) to increase the yield and speed of machining. A good knowledge of the machine properties is important to increase the speed while still maintaining stable cutting with low tool usage.To make models of the machine is therefore important and in machining a common way to extract the dynamic properties is frequency response measurement. One way is to use an impact hammer to excite the machine tool and measure the response. The problem is that a hammer can only be used on a non running machine. At Manufacturing and Metrology Systems division at KTH (MMS) a test method for contactless excitation has been developed that uses electromagnets to excite the machine tool. By using contactless testing it can be used on rotating machine tools without real cutting in materials. In this thesis a new test system for the contact less testing method has been designed and constructed to test if it is possible to do test on a bigger variety of rotating cutting machine tools. The results for the prototype is presented and evaluated.Dagens tillverkningsindustri arbetar för att utrsutningens totala effiktivitet ska höjas genomatt öka hastigheten och minska material- och verktygsanvändningen vid bearbetningen utan att minska kvalitén på slutprodukten. För att öka hastigheten krävs en god kännedom om maskinens egenskaper för att maskinen ska arbeta under stabila förhållanden där också verktygets slitage minskas. Att ta fram modeller över maskinen är därför viktigt och inom skärande bearbetning är frekvensresponsmätning ett sätt att få ut de dynamiska egenskaperna av det skärandeverktyget. En vanlig testmetod är att med en hammare exitera verktyget och mäta responsen. Problemet är dock att hammaren bara kan mäta vid stillastående maskin. Vid MMS har en testmetod för kontaktlös exitering tagits fram där elektromagneter användsför exiteringen. På så sätt kan testet utföras på roterande verktyg utan att man behöver förbruka material. I detta arbete har ett nytt testsystem för denna testmetod designats och konstruerats för att testa om det är möjligt med testning på flera storlekar på maskiner för skärandebearbetning. Resultaten för prototypen presenteras och utvärderas.