Tesi sul tema "Usinage – Qualité – Contrôle"
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1
Bajic, Eddy. "Intégration du contrôle qualité en production automatisée : application à un îlot automatisé de fabrication de pièces mécaniques". Nancy 1, 1988. http://www.theses.fr/1988NAN10015.
2
Chouhad, Hassan. "Towards online metrology for proactive quality control in smart manufacturing". Thesis, Paris, HESAM, 2022. http://www.theses.fr/2022HESAE021.
Abstract (sommario):
Dans l’industrie de fabrication traditionnelle, la métrologie est un élément essentiel de sanction de la qualité en bout de la chaîne de production. L’innovant dans le concept de la fabrication intelligente conduit à un repositionnement de la métrologie qui devient proactive au cœur même de la production pour fabriquer dès le départ une première pièce conforme. L’objet de cette thèse est donc de proposer une approche méthodologique pour le développement d'un système proactif, augmenté par des modèles d’intelligence artificielle IA, de contrôle en usinage de la conformité d’un produit à un cahier des charges et de caractériser ses défauts. Pour cela, une première étude sur l’aspect de surface a été réalisée en recueillant des images à haute résolution de fils de cuivre revêtus et découpés pouvant présenter des défauts. Les images, prises par un système de vision par ordinateur basé sur l'imagerie confocale chromatique, ont été utilisées pour générer différents modèles d'intelligence artificielle. Ce traitement consiste à faire de la segmentation et de la classification des défauts observés. En comparant la précision et le temps de traitement des modèles d'IA, l'apprentissage par transfert utilisant le modèle de mobile-net a montré de meilleures performances. Afin d'élargir l'étude de l'évaluation de la qualité de surface, des mesures de profil de surface sur machine-outil ont été effectuées à l'aide de capteurs confocaux chromatiques sans contact. Deux approches ont été réalisées : i) le fraisage de l'aluminium sans signature d’usure d’outil de coupe et ii) le fraisage du titane en tenant compte de la signature de l'usure de l'outil de coupe. Dans les deux configurations de coupe, les paramètres d’usinage, les profils de rugosité de surface et les efforts d’enlèvement de matière ont été enregistrés pour construire une base de données pour l'entraînement des modèles de prédiction par apprentissage automatique. Les résultats ont montré que le modèle XGboost a présenté la meilleure performance de prédiction et ce pour les deux scénarios. En considérant le temps de coupe dans le fraisage du titane, le modèle de prévision de séries temporelles ARIMA a été appliqué pour suivre l'évolution de la rugosité en fonction de l'usure de l'outil. L’analyse moyenne mobile autorégressive intégrée a permis de suivre l’évolution de la rugosité en fonction de la signature d’usureIn the traditional manufacturing industry, metrology is an essential element in sanctioning quality at the end of the production line. The innovation brought by concept of smart manufacturing leads to a repositioning of metrology to be proactive at the heart of production by performing the so-called first-time-right manufacturing of parts. The goal of this thesis is therefore to propose a methodological approach for the development of a proactive system, enhanced by AI models, to control the conformity of a product to a specification during machining and to characterize its defects. For this purpose, a first study on the surface aspect was carried out by collecting high-resolution images of coated and cut copper wires that may present defects. The images, taken by a computer vision system based on chromatic confocal imaging, were used to generate different artificial intelligence models. These models can perform segmentation and classification of observed defects. When comparing the accuracy and processing time of the AI models, transfer learning using the mobile-net model showed better performance. To extend the study of surface quality assessment, surface profile measurements on machine tools were performed using non-contact chromatic confocal sensors. Two approaches were performed: i) milling aluminum without tool wear signature, and ii) milling titanium with tool wear signature. In both cutting configurations, machining parameters, surface roughness profiles, and cutting forces were measured to build a dataset for training the prediction models by machine learning. The results showed that the XGboost model presented the best prediction performance and for both scenarios i) and ii). By considering the cutting time in titanium milling, the autoregressive integrated moving average time series prediction model was applied to track the evolution of roughness with tool wear
3
Mawissi, Kwamivi. "Modèles de représentation et de définition d'outillages de forme complexe : application à le génération automatique de processus d'usinage". Cachan, Ecole normale supérieure, 1995. http://www.theses.fr/1995DENS0001.
Abstract (sommario):
Ce mémoire porte sur l'automatisation de la fonction de préparation a la fabrication permettant de passer de la conception des pièces brutes forgées à la définition et la fabrication des outillages. Notre apport se traduit principalement par la construction d'un modèle de représentation d'outillages qui établit le lien entre les différentes fonctions de production, et l'élaboration d'une méthode originale de génération du processus d'usinage des outillages. Nous proposons un modèle de representation d'outillages, permettant la conceptualisation des données de définition d'ordre géométrique et technologique suivant les aspects sémantiques, structurels et topologiques. Du point de vue des deux premiers aspects, la conceptualisation des données nous a permis de définir quatre éléments génériques (entité complexe, macro-entité, primitive et méta-primitive) qui servent de base a la représentation d'outillages. De plus, nous proposons une description formelle des interférences géométriques entre les éléments permettant de représenter à la fois les topologies locales et globales. Notre méthode de génération du processus d'usinage des outillages est basée sur la notion d'état d'usinage qui s'appuie à la fois sur les informations définies dans le modèle de représentation d'outillages et sur des connaissances d'usinage traduisant le savoir-faire des outilleurs. A cet effet, nous présentons une formalisation pertinente des connaissances d'usinage a partir de laquelle sont construits les états. Pour cette construction, nous avons adopte une démarche semi-ascendante de génération d'états d'usinage. La spécification de ces états, ainsi que la définition et l'ordonnancement des séquences d'usinage correspondantes conduisent à l'élaboration d'une gamme d'usinage des outillages. Enfin, nous validons notre approche sur un exemple industriel. La maquette informatique développée permet d'implémenter les taches de génération de gamme et d'unifier l'ensemble des données de représentation d'outillages dans un modèle objet homogène pour une exploitation pertinente et cohérente des liens existant entre ces données
4
Motta, Mariane Prado. "Contribution à l’étude de systèmes de surveillance de l'usinage basés sur des méthodes d‘apprentissage machine et des mesures de vibrations, efforts et température de coupe". Electronic Thesis or Diss., Université de Lorraine, 2022. http://www.theses.fr/2022LORR0296.
Abstract (sommario):
L'usinage est un processus de fabrication d'une grande importance économique qui se base sur l'utilisation d'un outil de coupe affuté pour couper et enlever mécaniquement de la matière d'une pièce afin d'obtenir une géométrie souhaitée. Compte tenu des exigences toujours croissantes en termes de qualité, de variabilité des produits et de réduction des coûts, les systèmes de surveillance de l'état des outils ainsi que de la qualité de la pièce usinée, basés sur des techniques du domaine de l'intelligence artificielle (IA), constituent une solution potentielle pour en avoir des processus de fabrication plus fiables et économiques. Les récents développements dans le domaine de l'IA, ont montré un grand potentiel pour transformer le domaine de la fabrication avec des outils avancés dédiés à l'analyse et à la modélisation des données. En particulier, les algorithmes d'apprentissage machine supervisé (ML), constituent un outil puissant pour modéliser les relations complexes entre les variables d'entrée et de sortie sur la base d'un ensemble de données contenant des exemples, c'est-à-dire, de paires d'entrées-sorties. Néanmoins, l'un des principaux inconvénients de ces techniques de modélisation est qu'une grande quantité de données, généralement obtenues par la réalisation d'expériences (souvent longues et coûteuses à réaliser), est nécessaire pour former des modèles précis et fiables. Ce qui limite l'applicabilité de ces types de modèle dans un contexte industriel. Compte tenu de ce contexte, l'étude menée vise à contribuer à l'identification de méthodologies pour le développement de modèles ML dédiés à la surveillance d'usinage en conditions industrielles, dans lesquelles le temps et les ressources pour la réalisation d'expériences sont souvent limités. A cet effet, il est considéré dans cette étude que, bien que les expériences puissent parfois être coûteuses, dans l'industrie, il est courant qu'avant de lancer des productions d'usinage avec un nouvel outil ou un nouveau matériau, des expériences de réglage soient effectuées afin de déterminer les paramètres de coupe les plus appropriés pour réaliser cette production. Compte tenu de cette nécessité (ou recommandation), il sera investigué dans cette thèse, les performances prédictives qui peuvent être atteintes si des données, issues de ces expériences de réglage, sont utilisées pour générer des modèles prédictifs pour la surveillance de l'usinage. Plus précisément, des expériences de réglage issues de la méthodologie normalisée Couple-Outil-Matière (NF E 66-520) sont considérées. Soucieux d'obtenir de bonnes performances prédictives avec une quantité limitée de données expérimentales, des capteurs pour la mesure des efforts, de la température et des vibrations de coupe sont choisis comme instrumentation du système de surveillance à développer, en raison de ses relations étroites avec la cinématique du procédé d'usinage. A ce propos, une attention particulière est accordée à l'étape d'ingénierie des caractéristiques. Autrement dit, le processus qui consiste à transformer les données brutes disponibles, par exemple, les signaux enregistrés par les capteurs, en caractéristiques, c'est-à-dire, des informations, représentant plus précisément le problème sous-jacent au modèle prédictif. Finalement, étant donné que, dans l'industrie, le changement de référence de l'outil de coupe peut se produire assez souvent, il sera aussi étudié si les modèles développés pour un type d'outil de coupe cible peuvent être appliqués à d'autres types d'outils légèrement différents (variations sur le rayon de bec, substrat et revêtement) et si, pour l'entrainement de modèles ML, l'utilisation de bases de données plus volumineuses, mais contenant des observations relatives pas seulement l'outil cible, mais aussi à d'autres outils légèrement différents de celle-ci, sera plus avantageuse, par rapport à l'utilisation d'une base de données moins volumineuse, mais spécifique à l'outil cibleMachining is an economically important manufacturing process that relies on the use of a sharpened cutting tool to mechanically cut and remove material from a part to achieve a desired geometry. Given the ever-increasing demands for quality, product variability and cost reduction, tool condition and workpiece quality monitoring systems based on artificial intelligence (AI) techniques are a potential solution are a potential solution for a more reliable and economical manufacturing processes. Recent developments in the field of AI, have shown great potential to transform the manufacturing domain with advanced tools dedicated to data analysis and modeling. In particular, supervised machine learning (ML) algorithms are a powerful tool for modeling complex relationships between input and output variables based on a dataset containing examples, i.e., input-output pairs. Nevertheless, one of the main drawbacks of these modeling techniques is that a large amount of data, usually obtained through experiments (often long and expensive to perform), is required to train accurate and reliable models. This fact limits the applicability of these types of models in an industrial context. Considering this context, this study aims to contribute to the identification of methodologies for the development of ML models dedicated to machining monitoring within industrial conditions, in which time and resources for the realization of experiments are often limited. For this purpose, it is considered in this study that, although experiments can be onerous, in the industry it is common that, before starting large scale machining productions with a new tool or material, setup experiments are performed to determine the most appropriate cutting parameters to perform that production. Given this need (or recommendation), it will be investigated in this thesis, the predictive performances that can be achieved if data, obtained from these tuning experiments, are used to generate predictive models for machining monitoring. More precisely, setting experiments from the standardized methodology Couple Tool-Material protocol (NF E 66-520) are considered. In an effort to obtain good predictive performance with a limited amount of experimental data, sensors for measuring cutting forces, temperature and vibrations are chosen as instrumentation for the monitoring system to be developed, given its close relationship with the kinematics of the machining process. In this matter, special attention is given to the feature engineering step. That is, the process of transforming the available raw data, for example, the signals recorded by the sensors, into features, i.e., information, that more accurately represent the problem underlying the predictive model. Finally, since in the industry the changes in cutting tool reference can occur quite often, it will also be investigated whether the models developed for a given target tool can be applied to other slightly different tools (variations on nose radius, substrate and coating) and whether, for the training of ML models, the use of larger databases, but containing observations related not only to the target tool but also to other tools slightly different from it, will be more advantageous, compared to the use of a smaller database specific to the target tool
5
Dutilh, Vincent. "Maîtrise de l'intégrité de surface par la surveillance d'usinage sur les pièces critiques en superalliage de turbomoteurs aéronautiques". Phd thesis, Toulouse, INPT, 2011. http://oatao.univ-toulouse.fr/15642/1/Dutilh.pdf.
Abstract (sommario):
Les travaux présentés dans cette thèse s'inscrivent dans le cadre du projet européen ACCENT sur la maîtrise de l'intégrité de surface par la surveillance lors de l'usinage des pièces critiques aéronautiques. Des études antérieures ont montrées que des anomalies générées lors de l'usinage peuvent induire un abattement sur la tenue en fatigue des pièces. Dans ce contexte, l'objectif de ces travaux est de modéliser la relation entre l'intégrité de surface et les signaux enregistrés lors du perçage de l'Udimet®720. A partir d'une démarche expérimentale basée sur le Couple-Outil-Matière et les plans d'expériences, une caractérisation de l'usure de l'outil, de l'intégrité de surface et des signaux enregistrés a été effectuées en fonction des conditions d‘usinage et du contexte de l'opération (lubrifiant, dureté matière). Cette caractérisation à permis d'établir des corrélations entre les caractéristiques de l'intégrité de surface et celles des signaux. Ces corrélations ont été modélisées par des méthodes directes et statistiques, afin de mettre en avant la pertinence des capteurs de puissance, d'efforts et d'accélération par rapport aux anomalies d'usinage. Ainsi les capteurs permettent la prédiction de la couche de matière affectée par l'opération quelque soit le contexte d'usinage.
6
Remenaric, Hajak Mateja. "Study of ribonucleoprotein particle biogenesis and quality control by a novel technique using bacterial Rho factor as a tool". Thesis, Orléans, 2016. http://www.theses.fr/2016ORLE2013/document.
Abstract (sommario):
Chez les eucaryotes, l’information génétique est transcrite en ARN messager qui subit plusieurs étapes de maturation et évènements d’assemblage avant d’être exporté hors du noyau. Ces modifications du transcrit sont effectuées par de nombreux facteurs protéiques recrutés au transcrit naissant, formant ainsi une particule ribonucléoprotéique (mRNP). La biogenèse du mRNP est étroitement liée avec la transcription et le contrôle qualité afin d’assurer l’efficacité et l’exactitude de la production de mRNPs matures. Des études récentes suggèrent que les membres du complexe THO-Sub2 pourraient être des facteurs cruciaux dans le couplage de la transcription, de la biogénèse du mRNP et de l’export. Dans notre groupe, nous avons mis en oeuvre un essai novateur pour étudier la biogénèse du mRNP et le contrôle qualité, basé sur l’expression du facteur Rho bactérien dans Saccharomyces cerevisiae. Rho interfère avec l’assemblage adéquat du mRNP et génère des transcrits aberrants qui sont dégradés par la machinerie de dégradation nucléaire. Dans cette étude, nous avons utilisé le système expérimental Rho pour mieux comprendre Rrp6 et l’implication de l’exosome dans la dégradation des transcrits liée au contrôle qualité, ainsi que pour mieux caractériser le rôle et la fonction du complexe THO-Sub2 dans le processus de biogénèse du mRNP. Les résultats obtenus révèlent une différence intéressante dans le comportement des membres du complexe THO sous l’action de Rho et dévoilent leur dépendance à la liaison à l’ARN, ce qui n’aurait pas pu être observé avec d’autres techniques expérimentales. Cela confirme le potentiel attendu du système expérimental basé sur Rho dans l’étude des facteurs protéiques impliqués dans la biogénèse et le contrôle qualité du mRNPIn eukaryotes, the genetic information is transcribed into messenger RNA which undergoes various processing and assembly events prior to its export from the nucleus. These transcript modifications are performed by numerous protein factors recruited to the nascent transcript, thus making a messenger ribonucleoprotein particle (mRNP). mRNP biogenesis is tightly interconnected with both transcription and quality control to ensure efficiency and accuracy in production of mature mRNPs. Recent findings suggest that members of THO-Sub2 complex might be crucial factors in coupling transcription, mRNP biogenesis and export. In our group, we have implemented an innovative assay to study mRNP biogenesis and quality control, based on the expression of the bacterial factor Rho in Saccharomyces cerevisiae. Rho interferes with proper mRNP assembly and generates aberrant transcripts degraded by the nuclear degradation machinery. In this study, we use Rho experimental system to expand our findings on Rrp6 and exosome involvement in quality control degradation of transcripts, as well as to better characterize the role and function of THO-Sub2 complex in the process of mRNP biogenesis. Obtained results reveal an interesting difference in behavior of THO complex members upon Rho action and disclose their dependence on binding to the RNA, which could not be observed by other experimental techniques. This substantiates the expected potential of Rho-based experimental system in the study of protein factors involved in mRNP biogenesis and quality control
7
Cassady, Charles Richard. "Statistical quality control techniques using multilevel discrete product quality measures". Diss., This resource online, 1996. http://scholar.lib.vt.edu/theses/available/etd-06062008-151120/.
8
Gosselin, Ryan. "ON-LINE QUALITY CONTROL IN POLYMER PROCESSING USING HYPERSPECTRAL IMAGING". Thesis, Université Laval, 2010. http://www.theses.ulaval.ca/2010/26629/26629.pdf.
Abstract (sommario):
L’industrie du plastique se tourne de plus en plus vers les matériaux composites afin d’économiser de la matière et/ou d’utiliser des matières premières à moindres coûts, tout en conservant de bonnes propriétés. L’impressionnante adaptabilité des matériaux composites provient du fait que le manufacturier peut modifier le choix des matériaux utilisés, la proportion selon laquelle ils sont mélangés, ainsi que la méthode de mise en œuvre utilisée.
La principale difficulté associée au développement de ces matériaux est l’hétérogénéité de composition ou de structure, qui entraîne généralement des défaillances mécaniques. La qualité des prototypes est normalement mesurée en laboratoire, à partir de tests destructifs et de méthodes nécessitant la préparation des échantillons. La mesure en-ligne de la qualité permettrait une rétroaction quasi-immédiate sur les conditions d’opération des équipements, en plus d’être directement utilisable pour le contrôle de la qualité dans une situation de production industrielle.
L’objectif de la recherche proposée consiste à développer un outil de contrôle de qualité pour la qualité des matériaux plastiques de tout genre. Quelques sondes de type proche infrarouge ou ultrasons existent présentement pour la mesure de la composition en-ligne, mais celles-ci ne fournissent qu’une valeur ponctuelle à chaque acquisition. Ce type de méthode est donc mal adapté pour identifier la distribution des caractéristiques de surface de la pièce (i.e. homogénéité, orientation, dispersion).
Afin d’atteindre cet objectif, un système d’imagerie hyperspectrale est proposé. À l’aide de cet appareil, il est possible de balayer la surface de la pièce et d’obtenir une image hyperspectrale, c’est-à-dire une image formée de l’intensité lumineuse à des centaines de longueurs d’onde et ce, pour chaque pixel de l’image. L’application de méthodes chimiométriques permettent ensuite d’extraire les caractéristiques spatiales et spectrales de l’échantillon présentes dans ces images. Finalement, les méthodes de régression multivariée permettent d’établir un modèle liant les caractéristiques identifiées aux propriétés de la pièce. La construction d’un modèle mathématique forme donc l’outil d’analyse en-ligne de la qualité des pièces qui peut également prédire et optimiser les conditions de fabrication.The use of plastic composite materials has been increasing in recent years in order to reduce the amount of material used and/or use more economic materials, all of which without compromising the properties. The impressive adaptability of these composite materials comes from the fact that the manufacturer can choose the raw materials, the proportion in which they are blended as well as the processing conditions. However, these materials tend to suffer from heterogeneous compositions and structures, which lead to mechanical weaknesses. Product quality is generally measured in the laboratory, using destructive tests often requiring extensive sample preparation. On-line quality control would allow near-immediate feedback on the operating conditions and may be transferrable to an industrial production context. The proposed research consists of developing an on-line quality control tool adaptable to plastic materials of all types. A number of infrared and ultrasound probes presently exist for on-line composition estimation, but only provide single-point values at each acquisition. These methods are therefore less adapted for identifying the spatial distribution of a sample’s surface characteristics (e.g. homogeneity, orientation, dispersion). In order to achieve this objective, a hyperspectral imaging system is proposed. Using this tool, it is possible to scan the surface of a sample and obtain a hyperspectral image, that is to say an image in which each pixel captures the light intensity at hundreds of wavelengths. Chemometrics methods can then be applied to this image in order to extract the relevant spatial and spectral features. Finally, multivariate regression methods are used to build a model between these features and the properties of the sample. This mathematical model forms the backbone of an on-line quality assessment tool used to predict and optimize the operating conditions under which the samples are processed.
9
Binny, Diana. "Radiotherapy quality assurance using statistical process control". Thesis, Queensland University of Technology, 2019. https://eprints.qut.edu.au/130738/1/Diana_Binny_Thesis.pdf.
Abstract (sommario):
The work presented in this thesis was a step forward in applying statistics to the important problem of monitoring machine performance and quantifying optimal treatment quality assurance in radiotherapy. This research investigated the use of an analytical decision making tool known as Statistical Process Control (SPC) that employs statistical means to measure, monitor and identify random and systematic errors in a process based on observed behaviour. In this research, several treatment machine and planning system parameters were investigated and a method of calculating SPC based tolerances to achieve optimal treatment goals was highlighted in this study.
10
Faust, Justin E. "Increase efficiency using the six sigma methodologies". Online version, 2009. http://www.uwstout.edu/lib/thesis/2009/2009faustj.pdf.
11
Murphy, Terrence Edward. "Multivariate Quality Control Using Loss-Scaled Principal Components". Diss., Available online, Georgia Institute of Technology, 2004:, 2004. http://etd.gatech.edu/theses/available/etd-11222004-122326/unrestricted/murphy%5Fterrence%5Fe%5F200412%5Fphd.pdf.
Abstract (sommario):
Thesis (Ph. D.)--Industrial and Systems Engineering, Georgia Institute of Technology, 2005.Victoria Chen, Committee Co-Chair ; Kwok Tsui, Committee Chair ; Janet Allen, Committee Member ; David Goldsman, Committee Member ; Roshan Vengazhiyil, Committee Member. Vita. Includes bibliographical references.
12
Al, Mohammad Badera. "Quantitative MRI quality control using the ACR phantom". Thesis, Boston University, 2010. https://hdl.handle.net/2144/31496.
Abstract (sommario):
Thesis (M.A.)--Boston UniversityPLEASE NOTE: Boston University Libraries did not receive an Authorization To Manage form for this thesis or dissertation. It is therefore not openly accessible, though it may be available by request. If you are the author or principal advisor of this work and would like to request open access for it, please contact us at open-help@bu.edu. Thank you.
Recently, many studies have used T1 and T2 quantitative MRI in examining the brain and other body structures, to evaluate and follow up diseases, or simply for better understanding of the human body. Quality control on MRI scanners has been performed since the early eighties and nowadays the ACR MRI phantom is being used for the accreditation of the scanners, and quality control of their qualitative performance. In this study the same phantom is being used to obtain quantitative values of three regions in the phantom that might be used as reference for quantitative quality control. The results of the scans provided quantitative values that can be used as reference for the quality control of qMRI, and there was no difference after scanning the same regions twice. Further study is recommended to provide quantitative values for different MRI scanners strength to assure the use of ACR phantom as a tool for quality control of qMRI scanners.
2031-01-01
13
Al, Mohammad Badera. "Quantitative MRI quality control using the ACR phantom". Thesis, Boston University, 2012. https://hdl.handle.net/2144/32037.
Abstract (sommario):
Thesis (M.A.)--Boston UniversityPLEASE NOTE: Boston University Libraries did not receive an Authorization To Manage form for this thesis or dissertation. It is therefore not openly accessible, though it may be available by request. If you are the author or principal advisor of this work and would like to request open access for it, please contact us at open-help@bu.edu. Thank you.
Recently, many studies have used T1 and T2 quantitative MRI in examining the brain and other body structures, to evaluate and follow up diseases, or simply for better understanding of the human body. Quality control on MRI scanners has been performed since the early eighties and nowadays the ACR MRI phantom is being used for the accreditation of the scanners, and quality control of their qualitative performance. In this study the same phantom is being used to obtain quantitative values of three regions in the phantom that might be used as reference for quantitative quality control. The results of the scans provided quantitative values that can be used as reference for the quality control of qMRI, and there was no difference after scanning the same regions twice. Further study is recommended to provide quantitative values for different MRI scanners strength to assure the use of ACR phantom as a tool for quality control of qMRI scanners.
2031-01-02
14
Kuong-Lau, Kok-kin. "Quality assurance resource allocation using expert opinion and optimization". Diss., Georgia Institute of Technology, 1985. http://hdl.handle.net/1853/24331.
15
Flores-Cerrillo, Jesus MacGregor John F. "Quality control for batch processes using multivariate latent variable methods /". *McMaster only, 2003.
16
Lönnroth, Viktor. "Improving quality control in automation projects using simulation systems". Thesis, KTH, Skolan för elektroteknik och datavetenskap (EECS), 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-293928.
Abstract (sommario):
Automation systems are becoming more and more integrated in today’s society. The complexities of these systems are increasing and with this, the demand for high quality during the developmental phases. This poses a challenge for companies developing systems. One solution emerging form this issue is the use of simulations and virtual commissioning. In the thesis, the process of quality control and the effective use of simulations in automation system development projects are studied. The focus lies on the software part of the systems. The study was conducted as an interview study of personnel at an automation systems development company. After conducting the interviews, the information was analyzed. This was combined with general theory regarding quality control and testing methods in software development. The test methods of the quality control process were then combined with what was required by a simulator in order to preform them. The results of the thesis is a detailed picture of the quality control process. Systems are tested twice with the same testing hierarchy, first during development and then during commissioning. The difference is that during development, the final physical hardware and process system are not conceded to the software. This impacts the software system functionality and limiting its testability. Using simulations during development can reduce the disparity between the systems before and after deployment, improving quality. Considerations regarding the extent of simulation need to be made in order for the value of the simulators’ error removing potential to be higher than the cost of developing the simulator.Automationssystem blir mer och mer integrerade i dagens samhälle. Systemens komplexitet ökar och med det karven på hög kvalitet under utvecklingen. Detta blir en utmaning för de företag som utvecklar systemen. En lösning som är på uppgång för detta är användningen av simulering och virtuell driftsättning. I denna rapport studeras processen för kvalitetskontroll och effektiv användning av simulering i utvecklingsprojekt av automationssystem. Fokus ligger på mjukvarudelen av systemen. Studien är gjord som en intervjustudie av personal från ett automationsutvecklings företag. Efter intervjuerna analyserades materialet och kombinerades med generella teorier om kvalitetskontroll och testning i mjukvaruutveckling. Processens tester kombinerades sedan med vad som krävs av en simulator för att utföra dessa. Resultatet av detta arbete är för det första en detaljerad bild av kvalitetskontrolls processen. Detta visar att systemen tests två gånger med samma testhierarki, först under utvecklingen och sedan under driftsättningen. Skillnaden är att under utvecklingen saknas den riktiga hårdvaran och process systemet vilket påverkar mjukvarans funktionalitet och begränsar testbarheten. Genom att använda simulering under utvecklingen kan skillnaden mellan systemen före och efter distribution vilket ökar kvaliteten. Överväganden gällande vilken nivå av simulering som behövs för att värdet av simulerings potentiella förmåga att ta bort fel skall bli göre en kostande för att utveckla simuleringen.
17
Gandharva, Kumar. "Study of Effect of Coverage and Purity on Quality of Learned Rules". University of Cincinnati / OhioLINK, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1428048034.
18
Ko, Naonori. "Establishment of quality assurance and quality control measures for Boron Neutron Capture Therapy using microdosimetry". Kyoto University, 2020. http://hdl.handle.net/2433/253277.
19
Vera, Carrasco Luciano. "Sensory quality control of alcoholic beverages using fast chemical sensors". Doctoral thesis, Universitat Rovira i Virgili, 2010. http://hdl.handle.net/10803/9061.
Abstract (sommario):
Control de calidad sensorial de bebidas alcohólicas utilizando rápidos sensores químicosEn la presente tesis Doctoral, han sido aplicados dos sensores artificiales para el análisis de
bebidas alcohólicas: la nariz electrónica basada en la espectrometría de masas (MS) y la lengua
electrónica basada en la espectroscopía infrarroja con transformada de Fourier (FTIR). El
propósito fue desarrollar nuevas estrategias para analizar la autenticidad de estos productos,
desde un punto de vista sensorial, por medio de técnicas las espectrales antes mencionadas.
Adicionalmente, ha sido utilizado un espectrofotómetro UV-visible como ojo electrónico. El
trabajo presentado pretende ser un avance significativo hacia el desarrollo de un catador
electrónico mediante la fusión de los tres sensores químicos: nariz electrónica, lengua
electrónica y ojo electrónico.
Sensory quality control of alcoholic beverages using fast chemical sensors
In the present Doctoral Thesis, two chemical artificial sensors are applied to the analysis of
alcoholic beverages: the Mass Spectrometry (MS)-based electronic-noses and Fourier
transform infrared (FTIR)-based electronic-tongue. The aim was developing new strategies to
test the authenticity of these products, from a sensory point of view, by means of the spectral
techniques above mentioned. Additionally, has been used an UV-visible spectrophotometer as
electronic eye. The work presented wants to be a significant advance towards the development
of an electronic taster through the fusion of three chemical sensors: electronic nose, electronic
tongue and electronic eye.
20
Zhuohua, Qu. "Analytical quality control in shipping operation using six sigma principles". Thesis, Liverpool John Moores University, 2015. http://researchonline.ljmu.ac.uk/4520/.
Abstract (sommario):
A large number of benefits achieved through the successful implementation of Six Sigma programmes in different industries have been documented. However, very little research has been conducted on their applications in the shipping sector, especially in the Onshore Service Functions (OSFs) of shipping companies. Literature shows that heavy human involvement in the service industries such as shipping leads to a high volume of uncertainties which are difficult to be correctly and effectively measured or managed by simply using the traditional data analysis and statistical methods in Six Sigma. The aim of this study is to develop new quantitative analytical methodologies to enable the application and implementation of Six Sigma to improve the service quality of OSFs in shipping companies. Intensive investigations on the feasibility and effectiveness of the developed new methods and models through case studies in world leading container ship lines and shipping management companies have been carried out to ensure the achievement of the aim. This study firstly reviews the evolvement of quality control and some typical methods in the area, the development of Six Sigma, its tools and current applications, especially in the service industries. It is followed by a new framework of the Six Sigma implementation in the OSFs of shipping companies which is supported by a few real process excellence projects carried out in a world-leading ship line. In the process of the framework development, various issues and challenges appear largely due to the existence of uncertainties in data such as ambiguity and incompleteness caused by extensive subjective judgements. Advanced methods and models are developed to tackle the above challenges as well as complement the traditional Six Sigma tools so that the new Six Sigma methodologies can be confidently applied in situations where uncertainties in data exist at different levels. A new fuzzy Technique for Order Preference by Similarity to an Ideal Solution ii(TOPSIS) method is developed by combining the traditional TOPSIS, fuzzy numbers and interval approximation sets to facilitate the effective selection of Six Sigma projects and achieve the optimal use of resources towards the company objectives. A revised Failure Mode and Effects Analysis (FMEA) model is proposed in the “Analyse” step in Six Sigma to improve the capability of classical FMEA in failure identification in service industries. The new FMEA model uses the Analytical Hierarchy Process (AHP) and Fuzzy Bayesian Reasoning (FBR) approaches to increase the accuracy of failure identification while not compromising the easiness and visibility of the Risk Priority Number (RPN) method. Decision Making Trial and Evaluation Laboratory (DEMATEL) and Analytical Network Process (ANP) methods are incorporated with Fuzzy logic and Evidential Reasoning (ER), for the very first time to generate a Key Performance Indicators (KPIs) management method where the weights of indicators are rationally assigned by considering the interdependency among the indicators. Incomplete and fuzzy evaluations of the KPIs are synthesised in a rational way to achieve a compatible and comparable result. It is concluded that the newly developed Six Sigma framework together with its supporting quantitative analytical models has made significant contribution to facilitate the quality control and process improvement in shipping companies. It has been strongly evidenced by the success of the applications of the new models in real cases. The financial gains and continuous benefits produced in the investigated shipping companies have attracted a wider range of interests from different service industries. It is therefore believed that this work will have a high potential to be tailored for a wide range of applications across sectors and industries when the uncertainties in data exceed the ability that the classical Six Sigma tools and methods possess.
21
Dou, Yuchu. "Quantification and Quality Control of Extracellular Vesicles Using Capillary Electrophoresis". Thesis, Université d'Ottawa / University of Ottawa, 2020. http://hdl.handle.net/10393/41015.
Abstract (sommario):
Extracellular vesicles (EVs) gained significant interest within the last decade as a new source of biomarkers for the early detection of diseases and as a promising tool for therapeutic applications. As a result, a need for new methods for EV analysis and quantification has elevated. In this work, I apply Extracellular Vesicles Quantitative Capillary Electrophoresis (EVqCE) to determine (i) the apparent molecular weight of RNA in EVs, (ii) the number of intact EVs in a sample, and (iii) the degree of EV degradation after sonication, vortexing, freeze-thaw cycles and long storage. This separation method is demonstrated on EVs isolated from conditioned media of three different cancer cell lines and human urine samples. Here, I utilize capillary zone electrophoresis with laser-induced fluorescent detection to separate intact EVs from DNA and RNA impurities present in the sample. YOYO-1 dye is used to stain all DNA and RNA in the sample. After lysis of EVs with a detergent, encapsulated DNA and RNA are released. After additional RNase treatment of the EVs sample, RNA is enzymatically cleaved, leaving residual DNA only, in order to calculate the RNA concentration from EVs. Therefore, the initial concentration of intact EV is calculated based on the gain of a nucleic acid peak in capillary electrophoresis and an RNA calibration curve. EVqCE works in a dynamic range of EV concentrations from 10⁸ to 10¹⁰ particles/mL. The quantification process can be completed in less than one hour and requires minimum optimization for CE separation.
22
Wang, Duan Qiang. "Strain measurement using neutron diffraction". Thesis, Open University, 1996. http://oro.open.ac.uk/57651/.
Abstract (sommario):
This thesis contains a study of improvement and application of strain measurement technique using neutron diffraction. A dedicated neutron strain scanner - ENGIN, funded by Ee. has been developed at ISIS. It has two radial collimators, allowing for the first time, measurements taken simultaneously at two orthogonal directions; uses Pawley refinement permitting both whole pattern and individual peak profile analysis and its positioner allow's specimens weighing 250 kg to be placed with an accuracy of 100 um. Strain measurement using neutron diffraction has been investigated under two extreme circumstances: very shallow (within 1 mm near surface) and very deep in materials (hundred of mm). Near-surface measurement requires both the accurate determination of the effective measurement position associated with precise location of specimen, calculation of centroid and correction for an anomalous near-surface effect. The strain measurements on a shot-peened surface in titanium alloy were carried out using the methodology mentioned above. The result is comparable to that obtained from X-ray diffraction. The latter was exploited by studying the effect of wavelength-dependent attenuation in materials. Experiments and theoretical analysis on aluminium and iron show that the effect is small for a strain scanner using radial collimator and time-of-flight technique. However, the reduction of the diffraction peak intensity, as a function of the amount of material in the beam path, reveals that great care should be taken when measuring texture as a function of depth in materials. The neutron diffraction technique was applied to several sets of engineering strain measurements. Firstly, 3-D residual stresses surrounding a cold expanded hole in a high strength aluminium alloy plate were measured. The result agrees well with that from modified Sachs' method after taking the effect of gauge volume averaging into account. Second, measurements of strain distributions in a Q-joint under zero and 30 kN load have been carried out, which provides a confirmation of the excellence of the joint design as the fastener system has completely shielded the fastener hole from deleterious tensile strains under operational loading. Finally, calibration strain measurement for an energy dispersive neutron transmission spectrometer was performed for the first time and it is found that the transmission spectrometer is feasible for strain and phase transformation measurement.
23
Saxena, Abhinav. "Online web monitoring of card-spinning using image analysis". Thesis, Georgia Institute of Technology, 2003. http://hdl.handle.net/1853/8261.
24
Joyappa, Pallavi. "Pre production planning and leadtime reduction using Six Sigma". Online version, 2004. http://www.uwstout.edu/lib/thesis/2004/2004joyappap.pdf.
25
Mascolo, Rafael. "Concreto usinado : análise da variação da resistência à compressão e de propriedades físicas ao longo da descarga do caminhão betoneira". reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2012. http://hdl.handle.net/10183/75771.
Abstract (sommario):
A crescente utilização do concreto, que é o produto mais fabricado no mundo em termos de volume, somada à pressão do mercado por redução de custos com manutenção das exigências mínimas para segurança do projeto, tem impacto direto na importância e necessidade do controle de qualidade do material. Para concretos usinados, predominantes em grandes centros urbanos, as normas do país preconizam a não utilização dos 15% iniciais e finais do volume total de concreto do caminhão betoneira para fins de ensaio. No entanto, devido a maior facilidade e agilidade, é constatada como prática comum nos canteiros de obra da região a coleta de amostras logo da primeira porção de concreto descarregado. Considerando tal procedimento, fora do padrão preconizado por norma, somado à ausência de normatização para aferição da qualidade do misturador e uniformidade da mistura do concreto e a importância dos ensaios de controle de qualidade dos concretos perante a segurança das estruturas, a presente pesquisa tem como objetivo analisar as variações de resistência à compressão e de propriedades físicas do concreto ao longo da descarga da mistura em caminhão betoneira. A fim de atingir a meta proposta, realizaram-se coletas de amostras em cinco pontos distintos, ao longo da descarga do concreto do caminhão betoneira, para cada um dos 65 lotes (amassadas) avaliados, considerando três diferentes traços de concreto. Para cada ponto de coleta foram avaliados a resistência à compressão, o abatimento de tronco de cone e o teor de agregado graúdo. Estatisticamente, foi constatado que há amassadas em que a variação do ponto de coleta influencia na resistência à compressão, no entanto não se pode afirmar o mesmo considerando critérios da ABECE, adotados como parâmetro de análise na falta de normatização específica para o tema. Não houve a formação de um perfil representativo das variações de resistência conforme o ponto de coleta, diferentemente do teor de agregado graúdo, em que se pode visualizar claramente um perfil em que há concentração de brita nos pontos extremos, início e final da coleta. Em relação à consistência, de modo geral, houve uma redução do ponto inicial ao final, dentro dos limites de indicados por norma.The crescent utilization of concrete which in terms of volume, is the most produced product in the world, added to the pressure of the market to reduce the costs and maintenance of the safety minimum requirements of a project, make a direct impact on the material quality control’s importance and necessity. For ready-mixed concrete, mostly seen in large urban centers, the initial and final 15% usage of its total volume is not recommended by the country standards for test purposes. However, due to the ease, it is a common practice in construction sites of the region to collect samples once the first portion of the concrete is unloaded. Taking into account such procedure, which does not meet the standards recommended, added to the lack of standardization to assess the quality of the concrete mixer, the uniformity of the concrete mixture and the importance of the quality control tests of concrete under the safety of structures, the purpose of this research is to analyze the variations of the concrete strength when compressed and its physical properties along the discharge of the mixture made in a mixer truck. In order to achieve the proposed goal, there were sampling carried out at five different points along the discharge from the concrete mixer truck, for each of the 65 lots (batches) analyzed, considering three different types of concrete. Each sampling collected was analyzed by going through a slump test, compression strength and granulometry analysis. Statistically, it was proven that the sample point collection variation of some of the batches influences the compression strength, on the other hand the same cannot be found considering the ABECE criteria, used as analysis parameter in the absence of specific regulations for the subject. No representative profile of resistance variations based on the sample collection point was formed, in contrast to the coarse aggregate content, in which profile can be clearly seen a concentration of gravels at the extreme points, at the commencement and the end of the sample collection. Regarding its consistency, on the whole, there was a reduction from the initial and to the end point, respecting the regulations standards.
26
Guerra, Marcelo Del. "Desenvolvimento de apalpador de contato elétrico (\"touch trigger probe\") para atuação no processo de torneamento". Universidade de São Paulo, 2004. http://www.teses.usp.br/teses/disponiveis/18/18135/tde-12022016-174015/.
Abstract (sommario):
A utilização dos apalpadores acoplados a máquinas CNC se tornou uma realidade muito comum no mundo atual, principalmente devido à diminuição do tempo de preparação e possibilidades de realização de medições na própria máquina-ferramenta. Porém, ainda existem algumas barreiras a se transpor, como por exemplo, a dificuldade de programação, custo relativamente elevado e pouca literatura que trata exclusivamente a respeito da utilização dos apalpadores para medição nas máquinas-ferramentas. Nesse trabalho é realizada uma revisão bibliográfica sobre o uso dos apalpadores em ambiente industrial, discutindo-se as tecnologias utilizadas na geração do sinal de \"trigger\" e é proposto um novo modelo de apalpador de contato elétrico, de baixo custo, desenvolvido especialmente para atender as necessidades de medições em tornos CNC. Os testes em laboratório revelaram que a repetibilidade do protótipo construído foi de 0,003 mm dentro de uma confiabilidade de mais ou menos 3 \'sigma\' ou 99,73%. Concluiu-se que tais características são altamente compatíveis com os requisitos necessários para a maioria dos processos de torneamento.The use of touch trigger probes attached to CNC machines has become a world standard, especially due the reduction of setup time and the ability to promote work piece measurements on machine. However, some barriers like measurement routines programming difficulties, high costs of these equipments and the low number of technical literature about this subject, still need to be transposed. This work presents a review on the applications of touch trigger probes on companies shop floor, discussing the nowadays technologies used to generate the trigger signal. A new touch trigger probe model based on a simple electrical contact is specially developed to provide the measuring characteristics required for Lathes, with the needed characteristics and low cost. The tests of the probe developed in the laboratory shown a repeatability of 0,003 mm (more and less 3 \'sigma\' or 99,73%). Those characteristics are high compatible with the most needs of the industry.
27
Heidari, Fariba. "Quality of service routing using decentralized learning". Thesis, McGill University, 2009. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=115672.
Abstract (sommario):
This thesis presents several decentralized, learning-based algorithms for on-line routing of bandwidth guaranteed paths. The presented routing algorithms do not need any a-priori knowledge of traffic demand; they use only their locally observed events and update their routing policy using learning schemes. The employed learning algorithms are either learning automata or the multi-armed bandit algorithms. We investigate the asymptotic behavior of the proposed routing algorithms and prove the convergence of one of them to the user equilibrium. Discrete event simulation results show the merit of these algorithms in terms of improving the resource utilization and increasing the network admissibility compared with shortest path routing.We investigate the performance degradation due to decentralized routing as opposed to centralized optimal routing policies in practical scenarios. The system optimal and the Nash bargaining solutions are two centralized benchmarks used in this study. We provide nonlinear programming formulations of these problems along with a distributed recursive approach to compute the solutions. An on-line partially-decentralized control architecture is also proposed to achieve the system optimal and the Nash bargaining solution performances. Numerical results in some practical scenarios with well engineered networks, where the network resources and traffic demand are well matched, indicate that decentralized learning techniques provide efficient, stable and scalable approaches for routing the bandwidth guaranteed paths.
In the context of on-line learning, we propose a new algorithm to track the best action-selection policy when it abruptly changes over time. The proposed algorithm employs change detection mechanisms to detect the sudden changes and restarts the learning process on the detection of an abrupt change. The performance analysis of this study reveals that when all the changes are detectable by the change detection mechanism, the proposed tracking the best action-selection policy algorithm is rate optimal. On-line routing of bandwidth guaranteed paths with the potential occurrence of network shocks such as significant changes in the traffic demand is one of the applications of the devised algorithm. Simulation results show the merit of the proposed algorithm in tracking the optimal routing policy when it abruptly changes.
28
Conde, Erick F. "Environmental Sensor Anomaly Detection Using Learning Machines". DigitalCommons@USU, 2011. https://digitalcommons.usu.edu/etd/1050.
Abstract (sommario):
The problem of quality assurance/quality control (QA/QC) for real-time measurements of environmental and water quality variables has been a field explored by many in recent years. The use of in situ sensors has become a common practice for acquiring real-time measurements that provide the basis for important natural resources management decisions. However, these sensors are susceptible to failure due to such things as human factors, lack of necessary maintenance, flaws on the transmission line or any part of the sensor, and unexpected changes in the sensors' surrounding conditions. Two types of machine learning techniques were used in this study to assess the detection of anomalous data points on turbidity readings from the Paradise site on the Little Bear River, in northern Utah: Artificial Neural Networks (ANNs) and Relevance Vector Machines (RVMs). ANN and RVM techniques were used to develop regression models capable of predicting upcoming Paradise site turbidity measurements and estimating confidence intervals associated with those predictions, to be later used to determine if a real measurement is an anomaly. Three cases were identified as important to evaluate as possible inputs for the regression models created: (1) only the reported values from the sensor from previous time steps, (2) reported values from the sensor from previous time steps and values of other water types of sensors from the same site as the target sensor, and (3) adding as inputs the previous readings from sensors from upstream sites. The decision of which of the models performed the best was made based on each model's ability to detect anomalous data points that were identified in a QA/QC analysis that was manually performed by a human technician. False positive and false negative rates for a range of confidence intervals were used as the measure of performance of the models. The RVM models were able to detect more anomalous points within narrower confidence intervals than the ANN models. At the same time, it was shown that incorporating as inputs measurements from other sensors at the same site as well as measurements from upstream sites can improve the performance of the models.
29
Chang, Xiaolin. "On improving Internet quality of service using a control theoretic approach /". View abstract or full-text, 2005. http://library.ust.hk/cgi/db/thesis.pl?COMP%202005%20CHANG.
30
Rohani, Mehdiabadi Behrooz. "Power control for mobile radio systems using perceptual speech quality metrics". University of Western Australia. School of Electrical, Electronic and Computer Engineering, 2007. http://theses.library.uwa.edu.au/adt-WU2007.0174.
Abstract (sommario):
As the characteristics of mobile radio channels vary over time, transmit power must be controlled accordingly to ensure that the received signal level is within the receiver's sensitivity. As a consequence, modern mobile radio systems employ power control to regulate the received signal level such that it is neither less nor excessively larger than receiver sensitivity in order to maintain adequate service quality. In this context, speech quality measurement is an important aspect in the delivery of speech services as it will impact satisfaction of customers as well as the usage of precious system resources. A variety of techniques for speech quality measurement has been produced over the last few years as result of tireless research in the area of perceptual speech quality estimation. These are mainly based on psychoacoustic models of the human auditory systems. However, these techniques cannot be directly applied for real-time communication purposes as they typically require a copy of the transmitted and received speech signals for their operation. This thesis presents a novel technique of incorporating perceptual speech quality metrics with power control for mobile radio systems. The technique allows for standardized perceptual speech quality measurement algorithms to be used for in-service measurement of speech quality. The accuracy of the proposed Real-Time Perceptual Speech Quality Measurement (RTPSQM) technique with respect to measuring speech quality is first validated by extensive simulations. On this basis, RTPSQM is applied to power control in the Global System for Mobile (GSM) communication and the Universal Mobile Telecommunication System (UMTS). It is shown by simulations that the use of perceptual-based power control in GSM and UMTS outperforms conventional power control in terms of reducing the transmitter signal power required for providing adequate speech quality. This in turn facilitates the observed increase in system capacity and thus offers better utilization of available system resources. To enable an analytical performance assessment of perceptual speech quality metrics in power control, the mathematical frameworks for conventional and perceptual-based power control are derived. The derivations are performed for Code Division Multiple Access (CDMA) systems and kept as generic as possible. Numerical results are presented which could be used in a system design to readily find the Erlang capacity per cell for either of the considered power control algorithms.
31
Al-Saedi, Waleed Abood Baddai. "Optimal Control of Power Quality in Microgrids Using Particle Swarm Optimisation". Thesis, Edith Cowan University, Research Online, Perth, Western Australia, 2013. https://ro.ecu.edu.au/theses/611.
Abstract (sommario):
Driven by environmental protection, economic factors, conservation of energy resources, and technical challenges, the microgrid has emerged as an innovative small-scale power generation network. Microgrids consist of a cluster of Distributed Generation units that encompass a portion of an electric power distribution system and may rely on different energy sources. Functionally, the microgrid is required to provide adequate levels and quality of power to meet load demands. The issue of power quality is significant as it directly affects the characteristics of the microgrid’s operation. This problem can be defined as an occurrence of short to long periods of inadequate or unstable power outputs by the microgrid. In a stand-alone operation mode, the system voltage and frequency must be established by the microgrid, otherwise the system will collapse due to the variety in the microgrid component characteristics. The harmonic distortion of the output power waveforms is also a serious problem that often occurs because of the high speed operation of the converter switches. The long transient period is a critical issue that is usually caused by changing the operation mode or the load demand. Power sharing among the Distributed Generation units is also an important matter for sharing the load appropriately, particularly given that some renewable energy resources are not available continuously. In a utility connected microgrid, the reliable power quality mainly depends on the regulation of both active and reactive power, because the microgrid’s behaviour is mostly dominated by the bulk power system. Therefore, an optimal power control strategy is proposed in this thesis to improve the quality of the power supply in a microgrid scenario. This controller comprises an inner current control loop and an outer power control loop based on a synchronous reference frame and conventional PI regulators. The power control loop can operate in two modes: voltage-frequency power control mode and active-reactive power control mode. Particle Swarm Optimisation is an intelligent searching algorithm that is applied here for real-time self-tuning of the power control parameters. The voltage-frequency power controller is proposed for an inverter-based Distributed Generation unit in an autonomous operation mode. The results show satisfactory system voltage and frequency, high dynamic response, and an acceptable harmonic distortion level. The active-reactive power controller is adopted for an inverter-based Distributed Generation unit in a utility operation mode. This controller provides excellent regulation of the active and reactive power, in particular when load power has to be shared equally between the microgrid and utility. The voltage-frequency and active-reactive power control modes are used for a microgrid configured from two DG units in an autonomous operation mode. The proposed control strategy maintains the system voltage and frequency within acceptable limits, and injects sustained output power from one DG unit during a load change. The reliability of the system’s operation is investigated through developing a small-signal dynamic model for the microgrid. The results prove that the system was stable for the given operating point and under the proposed power controller. Consequently, this research reveals that the microgrid can successfully operate as a controllable power generation unit to support the utility, thus reducing the dependency on the bulk power system and increasing the market penetration of the micro-sources.
32
Shah, Parthiv Akshay. "Forecasting using the T-method". Diss., Rolla, Mo. : Missouri University of Science and Technology, 2008. http://scholarsmine.mst.edu/thesis/pdf/Shah_Parthiv_09007dcc80681cd6.pdf.
Abstract (sommario):
Thesis (M.S.)--Missouri University of Science and Technology, 2008.Vita. The entire thesis text is included in file. Title from title screen of thesis/dissertation PDF file (viewed June 18, 2009) Includes bibliographical references (p. 36-37).
33
Wilburn, Cathy A. "Using the Design Metrics Analyzer to improve software quality". Virtual Press, 1994. http://liblink.bsu.edu/uhtbin/catkey/902489.
Abstract (sommario):
Effective software engineering techniques are needed to increase the reliability of software systems, to increase the productivity of development teams, and to reduce the costs of software development. Companies search for an effective software engineering process as they strive to reach higher process maturity levels and produce better software. To aid in this quest for better methods of software engineering. the Design Metrics Research Team at Ball State University has analyzed university and industry software to be able to detect error-prone modules. The research team has developed, tested and validated their design metrics and found them to be highly successful. These metrics were typically collected and calculated by hand. So that these metrics can be collected more consistently, more accurately and faster, the Design Metrics Analyzer for Ada (DMA) was created. The DMA collects metrics from the files submitted based on a subprogram level. The metrics results are then analyzed to yield a list of stress points, which are modules that are considered to be error-prone or difficult for developers. This thesis describes the Design Metrics Analyzer, explains its output and how it functions. Also, ways that the DMA can be used in the software development life cycle are discussed.Department of Computer Science
34
Ben, Boubaker Moez, e Boubaker Moez Ben. "Non-destructive quality control of carbon anodes using modal analysis, acousto-ultrasonic and latent variable methods". Doctoral thesis, Université Laval, 2017. http://hdl.handle.net/20.500.11794/27843.
Abstract (sommario):
La performance des cuves d’électrolyse utilisées dans la production d’aluminium primaire par le procédé Hall-Héroult est fortement influencée par la qualité des anodes de carbone. Celles-ci sont de plus en plus variables en raison de la qualité décroissante des matières premières (coke et braie) et des changements de fournisseurs qui deviennent de plus en plus fréquents afin de réduire le coût d’achat et de rencontrer les spécifications des usines. En effet, les défauts des anodes, tels les fissures, les pores et les hétérogénéités, causés par cette variabilité, doivent être détectés le plus tôt possible afin d’éviter d’utiliser des anodes défectueuses dans les cuves et/ou d’apporter des ajustements au niveau du procédé de fabrication des anodes. Cependant, les fabricants d’anodes ne sont pas préparés pour réagir à cette situation afin de maintenir une qualité d'anode stable. Par conséquent, il devient prioritaire de développer des techniques permettant d’inspecter le volume complet de chaque anode individuelle afin d’améliorer le contrôle de la qualité des anodes et de compenser la variabilité provenant des matières premières. Un système d’inspection basé sur les techniques d’analyse modale et d’acousto-ultrasonique est proposé pour contrôler la qualité des anodes de manière rapide et non destructive. Les données massives (modes de vibration et signaux acoustiques) ont été analysées à l'aide de méthodes statistiques à variables latentes, telles que l'Analyse en Composantes Principales (ACP) et la Projection sur les Structures Latentes (PSL), afin de regrouper les anodes testées en fonction de leurs signatures vibratoires et acousto-ultrasoniques. Le système d'inspection a été premièrement investigué sur des tranches d'anodes industrielles et ensuite testé sur plusieurs anodes pleine grandeur produites sous différentes conditions à l’usine de Alcoa Deschambault au Québec (ADQ). La méthode proposée a permis de distinguer les anodes saines de celles contenant des défauts ainsi que d’identifier le type et la sévérité des défauts, et de les localiser. La méthode acousto-ultrasonique a été validée qualitativement par la tomographie à rayon-X, pour les analyses des tranches d’anodes. Pour les tests réalisés sur les blocs d’anode, la validation a été réalisée au moyen de photos recueillies après avoir coupé certaines anodes parmi celles testées.La performance des cuves d’électrolyse utilisées dans la production d’aluminium primaire par le procédé Hall-Héroult est fortement influencée par la qualité des anodes de carbone. Celles-ci sont de plus en plus variables en raison de la qualité décroissante des matières premières (coke et braie) et des changements de fournisseurs qui deviennent de plus en plus fréquents afin de réduire le coût d’achat et de rencontrer les spécifications des usines. En effet, les défauts des anodes, tels les fissures, les pores et les hétérogénéités, causés par cette variabilité, doivent être détectés le plus tôt possible afin d’éviter d’utiliser des anodes défectueuses dans les cuves et/ou d’apporter des ajustements au niveau du procédé de fabrication des anodes. Cependant, les fabricants d’anodes ne sont pas préparés pour réagir à cette situation afin de maintenir une qualité d'anode stable. Par conséquent, il devient prioritaire de développer des techniques permettant d’inspecter le volume complet de chaque anode individuelle afin d’améliorer le contrôle de la qualité des anodes et de compenser la variabilité provenant des matières premières. Un système d’inspection basé sur les techniques d’analyse modale et d’acousto-ultrasonique est proposé pour contrôler la qualité des anodes de manière rapide et non destructive. Les données massives (modes de vibration et signaux acoustiques) ont été analysées à l'aide de méthodes statistiques à variables latentes, telles que l'Analyse en Composantes Principales (ACP) et la Projection sur les Structures Latentes (PSL), afin de regrouper les anodes testées en fonction de leurs signatures vibratoires et acousto-ultrasoniques. Le système d'inspection a été premièrement investigué sur des tranches d'anodes industrielles et ensuite testé sur plusieurs anodes pleine grandeur produites sous différentes conditions à l’usine de Alcoa Deschambault au Québec (ADQ). La méthode proposée a permis de distinguer les anodes saines de celles contenant des défauts ainsi que d’identifier le type et la sévérité des défauts, et de les localiser. La méthode acousto-ultrasonique a été validée qualitativement par la tomographie à rayon-X, pour les analyses des tranches d’anodes. Pour les tests réalisés sur les blocs d’anode, la validation a été réalisée au moyen de photos recueillies après avoir coupé certaines anodes parmi celles testées.
The performance of the Hall-Héroult electrolysis reduction process used for the industrial aluminium smelting is strongly influenced by the quality of carbon anodes, particularly by the presence of defects in their internal structure, such as cracks, pores and heterogeneities. This is partly due to the decreasing quality and increasing variability of the raw materials available on the market as well as the frequent suppliers changes made in order to meet the smelter’s specifications and to reduce purchasing costs. However, the anode producers are not prepared to cope with these variations and in order to maintain consistent anode quality. Consequently, it becomes a priority to develop alternative methods for inspecting each anode block to improve quality control and maintain consistent anode quality in spite of the variability of incoming raw materials.A rapid and non-destructive inspection system for anode quality control is proposed based on modal analysis and acousto-ultrasonic techniques. The large set of vibration and acousto-ultrasonic data collected from baked anode materials was analyzed using multivariate latent variable methods, such as Principal Component Analysis (PCA) and Partial Least Squares (PLS), in order to cluster the tested anodes based on vibration and their acousto-ultrasonic signatures. The inspection system was investigated first using slices collected from industrial anodes and then on several full size anodes produced under different conditions at the Alcoa Deschambault in Québec (ADQ). It is shown that the proposed method allows discriminating defect-free anodes from those containing various types of defects. In addition, the acousto-ultrasonic features obtained in different frequency ranges were found to be sensitive to the defects severities and were able to locate them in anode blocks. The acousto-ultrasonic method was validated qualitatively using X-ray computed tomography, when studying the anode slices. The results obtained on the full size anode blocks were validated by means of images collected after cutting some tested anodes.
The performance of the Hall-Héroult electrolysis reduction process used for the industrial aluminium smelting is strongly influenced by the quality of carbon anodes, particularly by the presence of defects in their internal structure, such as cracks, pores and heterogeneities. This is partly due to the decreasing quality and increasing variability of the raw materials available on the market as well as the frequent suppliers changes made in order to meet the smelter’s specifications and to reduce purchasing costs. However, the anode producers are not prepared to cope with these variations and in order to maintain consistent anode quality. Consequently, it becomes a priority to develop alternative methods for inspecting each anode block to improve quality control and maintain consistent anode quality in spite of the variability of incoming raw materials.A rapid and non-destructive inspection system for anode quality control is proposed based on modal analysis and acousto-ultrasonic techniques. The large set of vibration and acousto-ultrasonic data collected from baked anode materials was analyzed using multivariate latent variable methods, such as Principal Component Analysis (PCA) and Partial Least Squares (PLS), in order to cluster the tested anodes based on vibration and their acousto-ultrasonic signatures. The inspection system was investigated first using slices collected from industrial anodes and then on several full size anodes produced under different conditions at the Alcoa Deschambault in Québec (ADQ). It is shown that the proposed method allows discriminating defect-free anodes from those containing various types of defects. In addition, the acousto-ultrasonic features obtained in different frequency ranges were found to be sensitive to the defects severities and were able to locate them in anode blocks. The acousto-ultrasonic method was validated qualitatively using X-ray computed tomography, when studying the anode slices. The results obtained on the full size anode blocks were validated by means of images collected after cutting some tested anodes.
35
Brooks, Christopher Richard. "Quantifying Appearance for Opaque Surfaces Using Spectral Bidirectional Reflectivity". BYU ScholarsArchive, 2019. https://scholarsarchive.byu.edu/etd/7498.
Abstract (sommario):
Quantifying the appearance of a surface is an important aspect in quality control. Becauseobjects at room temperature emit negligible amounts of radiation into the visible spectrum, aspectsof their appearance may be quantified using reflected light. Therefore, the appearance of opaquesurfaces may be quantified using measurements of the spectral, bidirectional reflectivity. However,measuring the spectral, bidirectional reflectivity of even one point at every set of incident andreflected directions is a time intensive process that is infeasible for quality control.The objective of this work was to determine whether a limited number of spectral, bidirectionalreflectance measurements may be used to characterize the appearance of an opaque surfaceat room temperatures. The results presented in this thesis demonstrate that measurements of thespectral bidirectional reflectivity in the visible spectrum at four sets of specular reflections - 20°,45°, 60°, and 85° - with a resolution of 5 nm may be used to quantify the appearance of an opaquesurface at room temperature. These measurements are converted into parameters called the bidirectionalreflectance appearance parameters (BRAPs). These BRAPs include L*, a*, b* (whichdefine the color of the surface), G20, G60, G85 (which define the gloss of the surface), and H(which describes the haze of the surface). It is shown that surfaces which appear similar havesimilar BRAPs and surfaces which appear different have different BRAPs.
36
Rainys, Algirdas. "Gaminio kokybės kontrolė taikant ultragarsą". Master's thesis, Lithuanian Academic Libraries Network (LABT), 2006. http://vddb.library.lt/obj/LT-eLABa-0001:E.02~2006~D_20060613_122907-33316.
Abstract (sommario):
In this paper are overviewed basic principles of ultrasonic inspection paying more attention to defect localization and size determination opportunities. Also there is done analysis of sound frequency influence on defect detection and sound wave attenuation.
37
Walia, Gursimran Singh. "Using error modeling to improve and control software quality an empirical investigation /". Diss., Mississippi State : Mississippi State University, 2009. http://library.msstate.edu/etd/show.asp?etd=etd-04032009-070637.
38
Bravaglieri, Lisa. "ClinQC: quality control of an X-ray imaging system using clinical images". Master's thesis, Alma Mater Studiorum - Università di Bologna, 2016. http://amslaurea.unibo.it/12172/.
Abstract (sommario):
The work presented in this thesis is part of a research project of Leiden University Medical Center (LUMC) in The Netherlands. It belongs to the field of Diagnostic Radiology analysed from a Medical Physics point of view. After a short overview of the weekly quality controls of an X-ray imaging device, performed using simple phantoms, the thesis focuses on a novel approach called ClinQC (Clinical images-based Quality Control): it has the purpose to monitor the stability of imaging devices, aiming at the early detection of changes in image quality or radiation dose, by deriving quality parameters from chest images of routine patient examinations. The ClinQC algorithm extracts the noise from clinical images and derives the main dose quantities. The noise study presented in this thesis comprehends a validation of the algorithm, performed in several ways: image deteriorations, simulations, phantom studies and real clinical examples. For dose and homogeneity studies only some preliminary results are presented. The thesis collects also some ideas of improvement that can be considered for the future versions of the algorithm and to extend the ClinQC project to other X-ray anatomies and imaging modalities.
The obtained similar results for the two compared methods prove that ClinQC is able to give immediate feedbacks of the quality of the imaging devices using patient images. It provides reliable, on-the-fly and sensitive parameters of the quality of the X-ray imaging system, that have the same physical meaning and similar relative variation as the quality indicators of the gold standard QClight method. It can be concluded that the ClinQC algorithm could be already applied in clinical practice, with the initial support of the QClight weekly quality control. In this way, a comparison between the two methods in a real test period will be a guide to find the necessary adjustments of the algorithm until the final version is being installed and stably used in clinical practice.
39
Eira, da Costa Ana Carina. "Analysis of mitochondrial quality control using a Drosophila model of Parkinson's disease". Thesis, University of Leicester, 2013. http://hdl.handle.net/2381/28019.
Abstract (sommario):
Parkinson’s disease (PD) is the most common neurodegenerative movement disorder. Despite recent advances, the cause for most PD cases remains unclear. The discovery of mutations in PINK1 (PTEN-induced putative kinase 1) reinforced the importance of mitochondrial impairment in PD. Mitochondria are essential organelles for energy generation in eukaryotic cells, whose compromise can eventually cause cell death. Multicellular organisms have evolved quality control mechanisms to ensure the viability of mitochondria and ultimately the cell. Molecular quality control through the mitochondrial chaperones and proteases acts to promote the proper folding of polypeptides and the degradation of misfolded or damaged proteins. When molecular quality control is overwhelmed, organellar quality control ensures mitochondrial recycling through a selective form of autophagy called mitophagy. PINK1 has been proposed to act in both molecular and organellar quality control, by modulating the activity of chaperones, namely HtrA2 and TRAP1, and acting on mitophagy through Parkin recruitment to damaged mitochondria. The work in this thesis provides evidence of a genetic interaction between Trap1, Pink1 and parkin in Drosophila melanogaster. Trap1 is essential to maintain mitochondrial and dopaminergic neuronal functions and is associated with resistance to stress. Importantly, neuronal expression of Trap1 is sufficient to rescue the Pink1 mutants. Moreover, the expression of Trap1 ameliorates parkin-mutant phenotypes and parkin expression suppresses Trap1-mutant phenotypes, suggesting that molecular and organellar quality control pathways act in parallel downstream from Pink1. p62 is an autophagy adaptor that acts in the PINK1/Parkin pathway, facilitating the aggregation and elimination of depolarised mitochondria through mitophagy. In this work it is shown that loss-of-function mutations in the Drosophila orthologue of p62, ref(2)P, result in a reduction in lifespan and age-dependent neurodegeneration. ref(2)P expression rescues the Pink1-mutant phenotypes and its presence is essential for the parkin-mediated rescue of Pink1 mutant flies.
40
Ghasemzadeh-Barvarz, Massoud. "Quality control of complex polymer materials using hyperspectral imaging associated with multivariate statistical analysis". Doctoral thesis, Université Laval, 2015. http://hdl.handle.net/20.500.11794/26025.
Abstract (sommario):
Dans la première étape de ce travail, des composites formulés à partir d'anhydride maléique greffé polyéthylène (MAPE) et de différentes charges de fibres de chanvre (entre 0 et 60%) ont été produits et analysés par imagerie NIR. Trois méthodes chimiométriques ont été utilisées puis comparées pour la prédiction des propriétés mécaniques, cartographier la distribution des constituants et détecter les défauts physiques des matériaux: la calibration multivariée traditionnelle basée sur la régression PLS, la résolution multivariée de courbes (MCR) et l’analyse d’images et la régression sur les images multivariées (MIA/MIR). Dans la deuxième partie de ce projet, une série de films multicouches complexes (échantillons industriels) ont été étudiés par imagerie NIR combinée à l’analyse d’images multivariée. Le potentiel et l'efficacité de la méthode proposée pour détecter les défauts causés par la (les) couche(s) manquant(es) ont été étudiés pour des films non imprimés et imprimés. Dans la dernière partie, les composites hybrides polypropylène (PP) / fibre de verre / fibre de lin ont été étudiés. L'effet de la teneur en fibres (0 à 40% en volume) et de la composition sur les propriétés mécaniques ont été investigués, ainsi que l’effet de l’exposition à l’eau et la dégradation thermique et aux rayons UV (vieillissement accéléré des matériaux). Les images de microscopie électronique à balayage (MEB) des composites non vieillis ont été analysées en combinant des méthodes d’analyse de texture et des méthodes multivariées. Enfin, l'imagerie NIR a été mise en œuvre sur des composites non vieillis et vieillis afin de prédire leurs propriétés finales ainsi que pour modéliser les variations de composition chimique et celles dues au vieillissement accéléré. En résumé, les résultats montrent que la combinaison de l'imagerie hyperspectrale et des méthodes statistiques multivariées est un outil puissant pour le contrôle de la qualité des composites polymères complexes. De plus, la méthode proposée est rapide et non destructive, elle peut être mise en œuvre en ligne, pour le contrôle de la qualité des matériaux composites. D'autre part, il a été démontré que l'analyse de la texture des images peut être appliquée à la quantification de la dispersion et du degré d’homogénéité de la distribution des charges dans des matériaux composites.In the first step of this work, maleic anhydride grafted polyethylene (MAPE)/hemp fiber composites with different filler concentration between 0 to 60% were analyzed by NIR imaging. Three chemometrics methods including Partial Least Squares (PLS), Multivariate Curve Resolution (MCR) and Multivariate Image Analysis/Multivariate Image Regression (MIA/MIR) were implemented and compared for predicting mechanical properties as well as mapping chemical compositions and material physical variations. In the second part of this project, a series of complex multilayer films (industrial samples) were investigated using NIR hyperspectral imaging and Multivariate Image Analysis (MIA). The potential and effectiveness of the proposed method for detecting defects caused by missing layer(s) were studied for unprinted and printed films. In the final part, polypropylene (PP)/glass/flax hybrid composites were studied. The effect of composition (fiber content between 0 and 40 vol%), as well as water, thermal and UV aging on mechanical properties was investigated. Then, Scanning Electron Microscopy (SEM) images of unaged hybrid composites were analyzed using texture analysis and multivariate methods. Finally, NIR imaging was implemented on unaged and aged composites to predict their final properties as well as to capture chemical composition and aging variations. In summary, the results show that combining hyperspectral imaging and multivariate statistical methods is a powerful tool for quality control of complex polymer composites. Since the proposed method is rapid and nondestructive, one can implement it for on-line quality control of finished plastic products. On the other hand, texture analysis and multivariate methods can be applied for quantifying the mixing aspects of composites.
41
Potgieter, Nardus. "Analysis of beer aroma using purge-and-trap sampling and gas chromatography". Pretoria : [s.n.], 2006. http://upetd.up.ac.za/thesis/available/etd-09282007-140010.
42
Mari, Joseph. "Using design for six sigma to design an equipment depot at a hospital". Diss., Online access via UMI:, 2007.
43
Chin, Bruce Lorenz. "An investigation in using artificial neural networks for quality control in the poultry industry". Thesis, Georgia Institute of Technology, 1993. http://hdl.handle.net/1853/17989.
44
Shobe, Kristin N. "Variable sampling intervals for control charts using count data". Thesis, Virginia Polytechnic Institute and State University, 1988. http://hdl.handle.net/10919/52076.
Abstract (sommario):
This thesis examines the use of variable sampling intervals as they apply to control charts that use count data. Papers by Reynolds, Arnold, and R. Amin developed properties for charts with an underlying normal distribution. These properties are extended in this thesis to accommodate an underlying Poisson distribution.Master of Science
45
Damineli, Bruno Luís. "Estudo de métodos para caracterização de propriedades físicas de agregados graúdos de resíduos de construção e demolição reciclados". Universidade de São Paulo, 2007. http://www.teses.usp.br/teses/disponiveis/3/3146/tde-09012008-120538/.
Abstract (sommario):
O baixo consumo de agregados de Resíduos de Construção e Demolição (RCD) deve-se, atualmente, à sua variabilidade natural e à falta de controle de sua qualidade, que limitam sua utilização em aplicações de maiores demandas, tais como concretos. Uma maneira usual de controle de agregados para concretos se dá por meio da determinação de sua porosidade, expressa pelas propriedades físicas de massa específica e absorção. O método utilizado para medir estas propriedades é a NM 53, norma derivada da ASTM C127. Porém, foi originalmente concebida para caracterizar agregados naturais, não sendo adequada sobre agregados de RCD reciclados. Nesse sentido, o objetivo deste trabalho é estabelecer um método rápido e preciso para controle de qualidade e triagem de agregados reciclados em usinas de reciclagem, o que poderia ampliar as possibilidades de campos para sua utilização. Para isso, foram estudados comparativamente três métodos distintos - NM 53, massa submersa no tempo e secagem - para determinação das propriedades físicas absorção e massa específica aparente (MEA) dos agregados reciclados. Os planejamentos experimentais basearamse em modelos estatísticos do tipo fatorial completo, que permitem melhorias do processo selecionado, de acordo com necessidades estabelecidas, através de análises de variáveis de possível significância às respostas. A adequação da NM 53 para utilização sobre agregados reciclados depende de: 1) aumento da saturação dos poros das amostras; 2) diminuição da perda de massa durante os ensaios; e 3) aumento da rapidez das determinações. Após a execução dos planejamentos experimentais, pôde-se propor um novo método para determinação da absorção e MEA de agregados graúdos de RCD reciclados. Tal método aumentou estatisticamente os valores de absorção medidos (aumento da saturação de poros), diminuiu a perda de massa das amostras durante a execução dos ensaios e ainda reduziu o tempo de caracterização de 48 horas (mínimo dispensado pela NM 53) para aproximadamente 4 horas. O método utiliza equipamentos simples e de baixo custo, possuindo potencial real para ser implantado para controle de qualidade de agregados de RCD reciclados em usinas de reciclagem.The low consumption of Construction and Demolition Waste (CDW) recycled aggregates happens, nowadays, because its natural variability and quality control absence that limit its use in applications with larger demands, such as concretes. One way of concrete aggregates control is done by determining its porosity, express by physical properties absorption and relative density. The method that measures its properties is the NM 53, standard derived from ASTM C127. But this standard was conceived to characterize natural aggregates, and is not appropriate on CDW recycled aggregates. In this way, the purpose of this work is to establish a quick and accurate method for quality control and selection of recycled aggregates in recycling plants, which could increase the possibilities of fields for its use. Thus, this work comparatively studied three distinct methods - NM 53, submerged mass in time and drying - for determining physical properties absorption and relative density of recycled aggregates. The experimental plannings were based on statistical models type Design of Experiments (DOE) that allow improvement on a selected process, in accordance with established needs, through analysis of possible significant variables for results. The adaption of NM 53 to recycled aggregates characterization depends on: 1) increase of sample pores saturation; 2) decrease of mass loss during the tests; and 3) increase of determination speed. After execution of experimental plannings, a new method for determining CDW coarse recycled aggregates physical properties could be proposed. This method statistically increased the measured absorption values (pores saturation increase), decreased mass loss during tests executions and reduced the characterization time from 48 hours (minimum used by NM 53) to approximately 4 hours. The method uses simple and low costs equipment, having real potential to be implemented for quality control of CDW recycled aggregates on recycling plants.
46
Jansson, Henrik. "Identification for control : using sensitivity information to improve quality of restricted complexity models". Licentiate thesis, KTH, Signals, Sensors and Systems, 2002. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-1424.
47
Sierra, Cadavid Andrea. "Multicomponent Quality Control Analysis for the Tomato Industry Using PortableMid-Infrared (MIR) Spectroscopy". The Ohio State University, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=osu1397132123.
48
Bhandari, Sumnima. "Quality improvement of product in plastics industry using six sigma approach". Online version, 2009. http://www.uwstout.edu/lib/thesis/2009/2009bhandaris.pdf.
49
Ariga, Eiji, Shigeki Ito, Shizuhiko Deji, Takuya Saze e Kunihide Nishizawa. "Development of dosimetry using detectors of diagnostic digital radiography systems". American Association of Physicists in Medicine, 2007. http://hdl.handle.net/2237/8818.
50
Armstrong, Bruce. "Using digital image analysis for assessing the quality of wheat and barley". Thesis, University of Ballarat, 2004. http://researchonline.federation.edu.au/vital/access/HandleResolver/1959.17/60071.
Abstract (sommario):
This thesis explores the issues involved in developing a relatively low-cost digital imaging analysis (DIA) system fot the quality assessment of wheat and barley using commonly available equipment. It also explores the capability of such a system to provide rapid and accurate assessments.Master of Applied Science by research