Global ETD Search

1	The effect of digital implant analog design on the trueness of implant analog position in additively manufactured digital implant models. Mata Mata, Severino Jose January 2020 (has links) No description available. Dentistry
2	Měření parametrů GNSS přijímačů / Measurement of GNSS receiver parameters Beneš, Jiří January 2020 (has links) Goal of this thesis is to propose and realize a viable method to determine static a dynamic parameters of GNSS receivers. Thesis begins with research of GNSS, foremostly determining position and associated uncertainties of measurement. Following chapter contains research of GNSS receivers, data flow and methods of evaluating parameters of such measurements. Summary of obtained information is then used to schedule measurements, assemble experiment and create evaluating metrics. Main selected evaluating metric is weighted histogram of deviations with extended information. Aplication of proposed metrics onto measurements of GNSS receivers augments available information of GNSS receiver accuracy for whole range of values. This metrics also supplies additional statistical information about course of measurement.
3	Modul kombinované globální satelitní navigace / Combined Global Navigation Satellite System Module Jurajda, David January 2013 (has links) The thesis objective is design of methodology focused on accuracy measurement in field of GPS/GLONASS receivers. Text is devided into five main parts. The first one is focused on GNSS technology. Second one deals with used coordinate systems and map projections (ETRS89, WGS84, UTM, Gauss-Krüger). Next part discusses statistical methods. Part four is focused on hardware. Then the final part describes experiment realization and obtained data analysis.
4	A standardized method for evaluating trueness and precision of intraoral scanners – in vitro accuracy Gashi, Tomor, Larsson, Eddie January 2014 (has links) Bakgrund. En gyllene standard för att bestämma noggrannheten för intraorala scannrarexisterar inte. Intraorala scannrars prestanda som ges av olika leverantörer är inte fulltjämförbara. Det finns ett behov att standardisera och ta fram oberoende försöksupplägg för att kunna jämföra intraorala scannrar.Mål. Målet med studien var att beskriva och utvärdera en ny metod för att bestämmanoggrannheten av intraorala scannrar genom ett standardiserat in vitro testförsök och attanvända metoden för att beräkna noggrannheten på en kommersiell intraoral scanner.Material och metod. SP Sveriges tekniska forskningsinstitut definierade dimensionerna avett sfäriskt testobjekt. Sfären besprutades med titanoxid och skannades 12 gånger med enkommersiell intraoral scanner. Scanningarna utvärderades med två metoder. Manuell metod: sfärens diameter uppmättes 12 gånger i ett första mjukvaruprogram för varje scanning genom att justera ett tvärsnittsplan. Automatisk metod: 12 nominella diametrar beräknades från ett andra mjukvaruprogram. Noggrannheten beräknades för varje testmetod och jämfördes.Resultat. Referensmätning: den definierade diameter var 4,9991±0,0001mm. Manuell metod: riktigheten var 25μm och precisionen var 10μm. Medelprecisionen inom scanningar var 4μm. Automatisk metod: Riktigheten var 26μm och precisionen var 11μm. Alla testvärden uppvisade stark statistisk deviation från referensvärdet, men väl inom ett kliniskt acceptabelt intervall.Slutsatser. Inom den här in vitro-studiens begränsningar, kan den beskrivna,standardiserade metoden användas manuellt eller med den automatiska funktionen Fittingsphere för att beräkna noggrannheten för intraorala scannrar. Fler studier på mer komplexa objekt behöver utföras. Dessutom uppvisade den intraorala scannern (TRIOS) hög riktighet och precision, jämförbar eller bättre än traditionella avtrycksmetoder inom tandvården. / AbstractBackground. There is no gold standard for determining the accuracy of intraoral scanners. The performances of intraoral scanners given by different manufacturers are not fully comparable. There is a need for standardized and independent test setups to enable the comparison of intraoral scanners.Objectives. The study’s aims were to describe and evaluate a new method for determining the accuracy of any intraoral scanner by means of a standardized geometrical in vitro test and to use this method for determining the accuracy of a commercial intraoral scanner.Material and methods. The Technical Research Institute of Sweden defined the dimensions of a spherical test object. The sphere was spray-coated with TiO2 and scanned 12 times with a commercial intraoral scanner. The scans where evaluated using two methods. Manual method: The diameter of the sphere was measured 12 times for each scan in a software application by adjusting a cross-sectional plane. Automatic method: 12 nominal diameters were obtained with a software application. The accuracy was calculated for each test method and compared. Results. Reference measurement: The defined diameter was 4.9991±0.0001mm. Manual method: Trueness was 25 µm and precision was 10 µm. Mean precision within scans was 4 µm. Automatic method: Trueness was 26 µm and precision was 11 µm. All test values showed sharp significant deviations from the reference value but were well within range of clinical acceptance.Conclusions. Within the limitations of this in vitro study, the standardized in vitro test described can be used manually or with the automatic function Fitting Sphere for determining the accuracy of intraoral scanners. Further studies need to be performed on more complex objects. The commercial intraoral scanner (TRIOS) demonstrates a high level of trueness and precision which is comparable with or better than that shown with traditional impression methods. dimensional measurement accuracy digital impression trueness precision intraoral scanner Medical and Health Sciences Medicin och hälsovetenskap
5	Estimating measurement uncertainty in the medical laboratory Placido, Rui January 2016 (has links) Medical Laboratories Accreditation is covered by ISO 15189:2012 - Medical Laboratories — Requirements for Quality and Competence. In Portugal, accreditation processes are held under the auspices of the Portuguese Accreditation Institute (IPAC), which applies the Portuguese edition (NP EN ISO 15189:2014). Accordingly, Medical Laboratories accreditation processes now require the estimate of measurement uncertainty (MU) associated to the results. The Guide to the Expression of Uncertainty in Measurement (GUM) describes the calculation of MU, not contemplating the specific aspects of medical laboratory testing. Several models have been advocated, yet without a final consensus. Given the lack of studies on MU in Portugal, especially on its application in the medical laboratory, it is the objective of this thesis to reach to a model that fulfils the IPAC’s accreditation regulations, in regards to this specific requirement. The study was based on the implementation of two formulae (MU-A and MU-B), using the Quality Management System (QMS) data of an ISO 15189 Accredited Laboratory. Including the laboratory’s two Cobas® 6000–c501 (Roche®) analysers (C1 and C2) the work focused three analytes: creatinine, glucose and total cholesterol. The MU-B model formula, combining the standard uncertainties of the method’s imprecision, of the calibrator’s assigned value and from the pre-analytical variation, was considered the one best fitting to the laboratory's objectives and to the study's purposes, representing well the dispersion of values reasonably attributable to the measurand final result. Expanded Uncertainties were: Creatinine - C1 = 9,60%; C2 = 5,80%; Glucose - C1 = 8,32%; C2 = 8,34%; Cholesterol - C1 = 4,00%; C2 = 3,54 %. ...[cont.]. 610.28
6	Une évaluation des performances analytiques de la spectroscopie sur plasma induit par laser (LIBS) / An evaluation of analytical performances of Laser-Induced Breakdown Spectroscopy (LIBS) Ismaël, Amina 21 November 2011 (has links) La spectroscopie sur plasma induit par laser (LIBS) est une technique d'analyse élémentaire couplant l'ablation laser dans le cas des échantillons solides, à la spectroscopie d'émission atomique. Malgré de nombreux avantages qui en font une technique de plus en plus attractive, la spectroscopie LIBS n'est pas encore reconnue comme méthode d'analyse quantitative. En effet, les problèmes d'hétérogénéité des échantillons, d'effets matrice, d'auto-absorption des raies d'émission et surtout de manque de répétabilité participent à la dégradation des performances analytiques de la spectroscopie LIBS. Dans le but de faire évoluer la technique, ces travaux de thèse consistent à réaliser un cas particulier de démonstration de l'évaluation des performances analytiques d'un système LIBS de laboratoire en intégrant des notions de qualité. L'exemple porte ici sur l'analyse d'échantillons d'aciers certifiés. Une première étude concerne le déroulement de l'optimisation du système pour l'analyse quantitative. L'effet des différents paramètres expérimentaux sur le signal LIBS étant complexe, un protocole méthodique est indispensable. Une étude paramétrique est donc ici proposée en vue de déterminer les conditions expérimentales les plus propices à l'analyse quantitative. Une fois optimisée, la méthode LIBS est ensuite caractérisée grâce aux principes classiques de la validation de méthode. La justesse ainsi que la fidélité de la méthode sont évaluées dans des conditions de répétabilité et de précision intermédiaire. Cette dernière étude montre des résultats prometteurs pour la technique. L'application d'une carte de contrôle montre néanmoins un manque de stabilité du système de laboratoire et permet d'enclencher des actions correctives en vue d'améliorer ses performances analytiques. / Laser-Induced Breakdown Spectroscopy (LIBS) is an elemental analytical technique which combines laser ablation with atomic emission spectroscopy. LIBS spectroscopy has many advantages but is not recognized as a fully quantitative method. Indeed, the problem of samples' heterogeneity, matrix effects, self-absorption of emission lines and the lack of repeatability deteriorate the analytical performances of LIBS. In order to improve this technique, the work presented in this thesis includes an example of analytical performances evaluation with the use of quality notions of a laboratory LIBS system. The method is here specially applied to the analysis of certified steel samples. A first study deals with the optimization of the LIBS system for the quantitative analysis. As the effect of the different experimental parameters on LIBS signal is complex, a methodical protocol is necessary. Here, a parametric study is proposed to determine the experimental conditions suitable for quantitative analysis. Once optimized, the LIBS method is then characterized with basics of method validation. The trueness and the precision of the method are evaluated in conditions of repeatability and intermediate precision. This study shows promising results for LIBS technique. The application of a control chart reveals however an instability of the laboratory system and enables to introduce corrective actions to improve its analytical performances. Ablation laser Analyse élémentaire Performances analytiques Optimisation de méthode Justesse Fidélité Carte de contrôle Laser ablation Elemental analysis Analytical performances Method optimization Trueness Precision Control chart
7	Influence of Annual Bluegrass on Putting Green Trueness and Control of Weedy Poa Species in Kentucky Bluegrass and Creeping Bentgrass Turf Rana, Sandeep Singh 08 December 2016 (has links) Annual bluegrass (Poa annua L.) and roughstalk bluegrass (Poa trivialis L.) are among the most troublesome grass weeds on golf courses throughout the United States. Herbicides for selective control of these weeds in cool-season fairways are limited and ineffective. Methiozolin is a new isoxazoline herbicide that controls annual bluegrass on putting greens and shows promise for possible weed control in fairways. Kentucky bluegrass (Poa pratensis L.) is among the most common turfgrass species used for golf fairways in the Northern United States and its response to methiozolin has scarcely been tested. A 2.5-yr field study was conducted at four Virginia locations to evaluate methiozolin efficacy for selective annual bluegrass and roughstalk bluegrass control in creeping bentgrass (Agrostis stolonifera L.) or Kentucky bluegrass fairways. Another study evaluated the response of 110 Kentucky bluegrass varieties to three rates of methiozolin. Annual bluegrass has long been presumed to impact putting green trueness, or the ability of the greens canopy to provide a smooth and directionally-consistent ball roll. Although much research has evaluated the impact of greens management on ball roll distance, no peer-reviewed research has evaluated how canopy surface factors, such as weedy annual bluegrass, will influence ball roll direction. Laboratory and field research was conducted to elucidate and overcome experimental errors that may be limiting assessment of ball directional imprecision caused by greens canopy anomalies. Techniques to minimize experimental error were employed in field studies at two Virginia golf courses to determine the influence of annual bluegrass on ball directional imprecision, bounce, and acceleration. Study results suggest that annual bluegrass patches in a creeping bentgrass putting surface can cause subtle increases in ball directional imprecision and bounce but several sources of error must be controlled before these effects can be measured. By using a mechanical putter to avoid directional errors associated with simulated-putt devices, selecting golf balls with balanced centers of gravity, eliminating legacy or "tracking" effects of repeated ball rolls via canopy brushing, and scoring ball direction 30 cm prior to terminal acceleration, we were able to detect an increase in ball directional imprecision of 8 mm m⁻¹ when balls rolled over a single patch of annual bluegrass compared to adjacent rolls on visually-pure creeping bentgrass. In herbicide efficacy studies, methiozolin-only treatments did not significantly injure creeping bentgrass or Kentucky bluegrass, reduce quality, or reduce normalized difference vegetative index regardless of application timings and rates. In general, fall applications of methiozolin reduced roughstalk bluegrass and annual bluegrass cover more than the spring-only treatments. At 1 year after the last treatment, methiozolin at 1500 g ha⁻¹ applied four times in fall at 2-wk intervals for two consecutive years controlled roughstalk bluegrass and annual bluegrass ≥85% and more consistently than other herbicides or treatment regimes. Spanning 110 Kentucky bluegrass varieties, a commercially-acceptable threshold of 30% Kentucky bluegrass injury required between 3.4 to more than 10 times the methiozolin rate needed for annual bluegrass control. Results indicate that annual bluegrass increases directional imprecision and bounce of golf balls rolling across a greens canopy. Methiozolin could be a viable herbicide for managing annual and roughstalk bluegrass in Kentucky bluegrass and creeping bentgrass fairways but weed control efficacy may be dependent on application timing. By measuring small differences in ball directional imprecision as influenced by greens canopy factors, future research efforts will aim to help turf managers choose appropriate greens management techniques. / Ph. D. Annual bluegrass Poa annua L. ball roll creeping bentgrass Agrostis stolonifera L. Kentucky bluegrass Poa pratensis L. methiozolin putting green trueness putting green uniformity and smoothness roughstalk bluegrass Poa trivialis L.
8	Analysis of Accuracy for Engine and Gearbox Sensors Dogantimur, Erkan, Johnsson, Daniel January 2019 (has links) This thesis provides a standardized method to measure accuracy for engine and gearbox sensors. Accuracy is defined by ISO 5725, which states that trueness and precision need to be known to provide a metric for accuracy. However, obtaining and processing the data required for this is not straight forward. In this thesis, a method is presented that consists of two main parts: data acquisition and data analysis. The data acquisition part shows how to connect all of the equipment used and how to sample and store all the raw data from the sensors. The data analysis part shows how to process that raw data into statistical data, such as trueness, repeatability and reproducibility for the sensors. Once repeatability and reproducibility are known, the total precision can be determined. Accuracy can then be obtained by using information from trueness and precision. Besides, this thesis shows that measurement error can be separated into error caused by the sensors and error caused by the measurand. This is useful information, because it can be used to assess which type of error is the greatest, whether or not it can be compensated for, and if it is economically viable to compensate for such error. The results are then shown, where it is possible to gain information about the sensors’ performance from various graphs. Between Hall and inductive sensors, there were no superior winner, since they both have their strengths and weaknesses. The thesis ends by making recommendations on how to compensate for some of the errors, and how to improve upon the method to make it more automatic in the future. statistical analysis engine gearbox sensor sensors rotation rotational speed differential pressure performance characteristics trueness precision accuracy Hall inductive induction gauge pressure reference hysteresis bias noise linearity non-linearity DEWESoft DAQ wheel tooth teeth absolute rotary encoder matlab XOR Gray binary LabView sampling measurement measuring statistisk analys motor växellåda sensor sensorer rotation rotationell hastighet fart differentiell tryck prestanda karaktäristik trueness precision accuracy noggrannhet onoggrannhet Hall induktiv induktion tryckskillnad referens hysteres bias avstånd brus linjäritet linearitet olinear olinjär olinearitet olinjäritet DEWESoft DAQ sampling mätning hjul tand tänder absolut rotationsgivare givare matlab XOR Gray binär LabView Elektroteknik och elektronik
9	Vad är god praxis för kalibrering och funktionskontroller av vågar inom läkemedelsindustrin / What is the best practice for calibration and routine testing of balances in the pharmaceutical industry Gourie, Roberto January 2022 (has links) I denna studie så ville AstraZenecas dispenseringsfunktion, som arbetar med att finfördelamaterial från sin bulkförpackning undersöka hur och med vilka frekvenser kalibreringar ochfunktionskontroller för deras vågar bör göras. Detta i hopp om att harmonisera en uppdateradoch förbättrad standard mellan siterna Gärtuna och Snäckviken. Standarder inom mätningslära är inget som läkemedelsföretag själva investerar resurser i, utanföljer det som farmakopéerna världen över publicerar i sina böcker. Däri återfinns allt som kantänkas behövas för tillverkning och utformning av läkemedel. Syftet med att kalibrera ochgenomföra funktionskontroller så ofta som AstraZeneca gör i dagsläget är för att vara förenligamed regelverk för att bli godkända vid inspektioner. Däremot finns risken attfunktionskontroller och kalibreringar genomförs med högre eller lägre frekvens än vad de bordegöras samt att irrelevanta tester vid dessa kontroller får alltför hög prioritering för att påvisa envågs förmåga att fungera som den ska. För att undersöka detta genomfördes det en kartläggning av hur AstraZeneca arbetar idag medvågkalibreringar och funktionskontroller. Denna behandlade både hur arbetet sker internt viaegna funktioner, men också externt via vågtillverkaren och valideringsfirmor. Dennainformation tillsammans med vad farmakopéerna och vågtillverkaren själva påstår är korrektarbetssätt blev ett tydligt och effektivt sätt att sålla bort överflödiga och i vissa fall irrelevantametoder som används på AstraZeneca idag. Utöver dessa finns det fenomen såsommätosäkerhet och störningselement som kan påverka varje vägning till den grad där resultatenär fullständigt missvisande, och i läkemedelsindustrins fall är dessa oacceptabla. Vid studiens slut kunde flera systematiska brister identifieras och rekommendationer för attmotverka eller lösa dessa gavs i enlighet med syftet om att nå god praxis för våganvändningen isamband med dispenseringsprocessen. Framtida förbättringsarbeten hade förenklats ocheffektiviserats till stor del om en fullständig digitalisering och övervakning avstörningselementen möjliggörs. / In this study that was commissioned by AstraZeneca's dispensing function that worksmainly by sub-dividing materials from its bulk packaging. They wanted to investigatehow and with what frequencies calibrations and routine testing for their balances shouldbe performed. This, with the purpose of harmonizing an updated and improvedstandard between the sites Gärtuna and Snäckviken. Measurement theory standards are not something that pharmaceutical companiesthemselves invest resources in but rather follow what pharmacopoeias around the worldpublish in their books. The books contain everything that may be needed for themanufacturing and design of medicines. The purpose of calibrating and performingroutine testing as often as AstraZeneca does today is to comply with regulations to beapproved during inspections. However, there is a risk that routine testing andcalibrations are performed at a higher or lower frequency than they should be, and thatirrelevant tests at these routine tests are given too high a priority to demonstrate abalances ability to function properly. To investigate this, a survey was conducted of how AstraZeneca works today withbalance calibrations and routine testing. The survey considered both how the work isdone internally via AstraZeneca’s own employees, but also externally via the balancemanufacturer and validation companies. This information, in combination with whatthe pharmacopoeias and the balance manufacturer themselves claim is the correct wayof operating, became a clear and effective way of sifting away superfluous and in somecases irrelevant methods used in AstraZeneca today. In addition to these, there arephenomena such as measurement uncertainty and external disturbance elements thatcan affect any weighing to the extent that the results are completely misleading, and inthe case of the pharmaceutical industry, such results would be unacceptable. At the end of the study, several systematic flaws or shortcomings could be identified andrecommendations to counteract or solve these were given in accordance with the aim ofachieving best practice for the use of balances in connection with the dispensingprocess. Future improvement work would have been greatly simplified and streamlinedif complete digitization and monitoring of the disturbance elements were made possible. Best practice scales balances calibration routine testing standard SOP dispensation measurement uncertainty measurement errors external disturbance elements non-linearity repeatability sensitivity eccentricity accuracy trueness pharmacopoeia FDA regulation regulatory documents God praxis våg kalibrering funktionskontroll standard SOP dispensering mätosäkerhet mätfel störningselement icke-linjäritet repeterbarhet känslighet excentricitet riktighet noggrannhet farmakopé läkemedelsverket styrdokument Engineering and Technology Teknik och teknologier

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