Dissertations / Theses on the topic 'Inspection qualité'
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1
Guermonprez, Philippe. "Inspection automatique des matériaux plans texturés." Valenciennes, 1994. https://ged.uphf.fr/nuxeo/site/esupversions/e4329f80-b368-4f43-a639-0f80c3bb838d.
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Qualité et flexibilité sont les deux atouts de l'industrie textile des pays industrialisés pour faire face à la concurrence. Pour jouer son rôle de référence, le contrôle qualité doit être automatisé. Insuffisantes, les machines actuelles doivent être améliorées tant au niveau des méthodes que des matériels: c'est ce qui a été fait dans le cadre d'un programme BRITE. Les travaux ont porté sur les méthodes et particulièrement sur l'extraction des défauts de leur contexte texture. La méthode proposée s'appuie sur un principe connu, la transformée de Fourier et débouche sur un filtrage nouveau permettant une détection de parties de défaut, qu'il faut donc compléter par une procédure spécifique de chainage intra et intercamera. Étendue aux tissus tissés teints, la méthode offre de nouvelles possibilités en matière de segmentation d'image colorée. La réalisation d'un prototype correspondant de machine d'inspection a permis de constater (pour des tissus monochromes) la qualité des résultats, à un type de défaut près et de garantir la faisabilité industrielle de cette machine. Pour les tisses teints, les tests sont probants mais demandent une validation industrielle.
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Barlet, Christophe. "Place et rôle de l’inspection-contrôle dans le champ des établissements et services sanitaires, sociaux et médico-sociaux." Thesis, Rennes 1, 2020. http://www.theses.fr/2020REN1G007.
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L’inspection-contrôle a connu plusieurs évolutions qui interrogent sa place et son rôle, en particulier dans le champ de cette étude. La multiplicité des acteurs et des procédures d’inspection-contrôle rend son appréhension complexe et interroge la nature juridique et le régime juridique applicables aux différents types de contrôles. Par ailleurs, l’inspection-contrôle apparaît aujourd’hui remise en question par la normalisation des pratiques professionnelles et des nouvelles démarches d’accompagnement et d’amélioration continue de la qualité dans les établissements et services du champ étudié. Ces démarches, dévolues à des autorités publiques ou des organismes privés, prennent la forme de la certification des établissements de santé, de l’accréditation des professionnels de santé, de l’évaluation des établissements et services sociaux et médico-sociaux ou encore de l’audit. Elles s’appuient largement sur le droit des autorisations et la contractualisation. Il convient ainsi de rechercher si une bonne activité de l’État, c’est seulement de la règle ou aussi de la régulation, si le contrôle a changé de nature, s’il s’est diversifié ou s’il a régressé au bénéfice d’autres activités plus souples sous l’influence du droit de la concurrence, du droit communautaire et de la situation budgétaire de l’État. La question de la juridicité de l’inspection en tant que contrôle particulier et son articulation avec les démarches qualité guident cette rechercheInspection-control has undergone several changes that question its place and role, particularly in the scope of this study. The multiplicity of actors and inspection-control procedures makes it complex to understand and questions the legal nature and legal regime applicable to the different types of controls. Furthermore, inspection and control now appears to be called into question by the standardization of professional practices and new approaches to support and continuously improve quality in the establishments and services in the field under study. These approaches, devolved to public authorities or private organizations, take the form of certification of health care institutions, accreditation of professionals in health care, evaluation of social and medico-social institutions and services, or auditing. They are largely based on licensing and contractualization law. It is thus necessary to investigate whether a good activity of the State is only rule-making or also regulation, whether control has changed in nature, whether it has diversified or whether it has regressed to the benefit of other, more flexible activities under the influence of competition law, Community law and the State's budgetary situation. The question of the legality of inspection as a particular control and its articulation with quality approaches guide this research
3
Tout, Karim. "Automatic Vision System for Surface Inspection and Monitoring : Application to Wheel Inspection." Thesis, Troyes, 2018. http://www.theses.fr/2018TROY0008.
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L'inspection visuelle des produits industriels a toujours été l'une des applications les plus reconnues du contrôle de qualité. Cette inspection reste en grande partie un processus manuel mené par des opérateurs et ceci rend l’opération peu fiable. Par conséquent, il est nécessaire d'automatiser cette inspection pour une meilleure efficacité. L'objectif principal de cette thèse est de concevoir un système d'inspection visuelle automatique pour l'inspection et la surveillance de la surface du produit. L'application spécifique de l'inspection de roues est considérée pour étudier la conception et l'installation du système d'imagerie. Ensuite, deux méthodes d'inspection sont développées : une méthode de détection des défauts à la surface du produit et une méthode de détection d’un changement brusque dans les paramètres du processus d’inspection non stationnaire. Parce que dans un contexte industriel, il est nécessaire de contrôler le taux de fausses alarmes, les deux méthodes proposées s’inscrivent dans le cadre de la théorie de la décision statistique. Un modèle paramétrique des observations est développé. Les paramètres du modèle sont estimés afin de concevoir un test statistique dont les performances sont analytiquement connues. Enfin, l'impact de la dégradation de l'éclairage sur la performance de détection des défauts est étudié afin de prédire les besoins de maintenance du système d'imagerie. Des résultats numériques sur un grand nombre d'images réelles mettent en évidence la pertinence de l'approche proposéeVisual inspection of finished products has always been one of the basic and most recognized applications of quality control in any industry. This inspection remains largely a manual process conducted by operators, and thus faces considerable limitations that make it unreliable. Therefore, it is necessary to automatize this inspection for better efficiency. The main goal of this thesis is to design an automatic visual inspection system for surface inspection and monitoring. The specific application of wheel inspection is considered to study the design and installation setup of the imaging system. Then, two inspection methods are developed: a defect detection method on the product’s surface and a change-point detection method in the parameters of the non-stationary inspection process. Because in an industrial context it is necessary to control the false alarm rate, the two proposed methods are cast into the framework of hypothesis testing theory. A parametric approach is proposed to model the non-anomalous part of the observations. The model parameters are estimated to design a statistical test whose performances are analytically known. Finally, the impact of illumination degradation on the defect detection performance is studied in order to predict the maintenance needs of the imaging system. Numerical results on a large set of real images highlight the relevance of the proposed approach
4
Macaire, Ludovic. "Inspection d'états de surfaces métalliques par vision linéaire : Application au contrôle qualité continu en sidérurgie." Lille 1, 1993. http://www.theses.fr/1993LIL10005.
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L'objectif de ce travail est la conception d'un système d'inspection automatique intégré dans l'atelier de l'aspect de bandes galvanisées, minimisées et laquées en defilement continu. L'inspection est effectuée par analyse des images lignes successives acquises par une caméra linéaire. Ces images représentent l'aspect de la bande qui, éclairée de manière particulière, défile en continu devant le dispositif de prise de vues. La stratégie choisie consiste à diviser l'inspection automatique en plusieurs procédures qui détectent et reconnaissent chacune un type de défaut spécifique. Cette stratégie permet l'implantation en parallèle des procédures de détection de défauts afin de respecter les contraintes du traitement en temps réel. Le développement des procédures de détection de défauts nous a conduits à proposer de nouvelles approches pour les problèmes essentiels suivants : la séparation et le dénombrement des modes d'un histogramme multimodal afin d'effectuer un seuillage adaptatif des images lignes acquises ; -la reconstruction des objets à partir d'images lignes binarisées de telle sorte qu'elle puisse s'effectuer en respectant les contraintes du traitement en temps réel ; la caractérisation de la texture des images lignes successives. Ce travail a abouti à l'intégration d'un système d'inspection automatique en atelier qui a permis de valider la faisabilité d'un tel système et de prouver sa réelle efficacité.
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Gama, Alves Isabel Teresa. "Le rôle de l'action publique pour la qualité dans l'agro-alimentaire en France : étude de cas de la filière lait." Toulouse 1, 1996. http://www.theses.fr/1996TOU10027.
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Le champ de l'action publique pour la qualité est devenu dans les années 1980 un champ d'action pensé à part entière, et dont l'établissement a eu lieu dans les années 1990 avec la définition d'un cadre juridique et institutionnel. Sachant que la qualité imprimée à un produit est liée non seulement à l'espace de sa production mais aussi à celui de sa circulation, nous pouvons appréhender la politique de qualité comme une mise en cohérence des "règles" propres à l'environnement dans lequel elle s'inscrit. Au regard de l'action publique et de la qualité, le secteur agro-alimentaire présente une ambigüité qui est le fruit d'une part de sa double insertion dans les mondes agricole et industriel et d'autre part d'une politique alimentaire. Dans ce cadre, l'intervention publique doit prendre en compte l'insertion de la qualité des modèles de production hétérogènes, dans des "mondes de production" différents, le postulat de base étant celui selon lequel la qualité est une construction sociale et le fruit de compromis. L'émergence de nouveaux acteurs et de nouvelles valeurs dans les années 1980 et 1990 peut ainsi clairement être notée au travers de nouveaux centres émetteurs de l'action publique et médiateurs. De plus, l'analyse de la façon dont l'action publique pour la qualité a évolué nécessite de prendre en compte les diverses négociations qui existent au sujet de la qualité et qui portent sur deux points : celui des réglementations, en particulier pour les signes officiels, et d'autres mesures qui les visent. Des changements se sont produits au niveau de l'articulation des mesures et des médiateurs. Ainsi, l'hétérogénéité à gérer lors du compromis se reflète dans les appareilsQuality has drawn more and more attention from governments in the 80's and public policies devoted to this point have been established in the 90's through specific laws and institutions. As quality of a product is related not only to its production but also to its marketing, we can define quality policies as a framework of "rules" related to this environment. From the points of views of public policies and quality, the foodstuff industry is in a special position as it is related both to agriculture and industry as well as to human health. Public policies cannot be defined independently of this framework including different kinds of production models. Therefore our central hypothesis was that quality is a social construction and results from compromises. The apparition of new actors as well as new values in the 80's and 90's has for consequences that public intervention used new channels and new mediations. Moreover, in order to analyze the evolution of public policies, one must take into account negotiations related to quality that concern different rules (and especially trademarks and other labels). Links between rules and mediators have also changed so that heterogeneity that has to be taken into account to get workable compromises has its counterpart in the public institutions specialized or not local and national level as well as the EU level. In conclusion, this dynamics and the new conception of the administration that delegate and negotiate more often than previously leads to place the analysis of quality policies as a multi-stage action
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Guitton, Philippe. "Une méthode de contrôle statistique de la qualité en fabrication continue : Icare (fondements théoriques et mise en oeuvre)." Rouen, 1987. http://www.theses.fr/1987ROUES040.
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Le système Icare, qui prend effet sur une fabrication en cours, dans laquelle sauf cas de dysfonctionnement, les probabilités d'apparition de défauts sont faibles, est de type évolutif; c'est-à-dire que la vérité du contrôle dépend, du nombre de défectueux récemment observés (dans la version Icare avec défectueux) ou du démérite récemment observé qui est fonction des défauts et familles de défauts rencontrés (dans la version Icare avec défauts). Le rythme des tirages des échantillons est caractérisé par les convoluées de lois uniformes sur un même support. Les principaux résultats théoriques concernent les calculs de la fraction inspectée moyenne, de la qualité moyenne après contrôle et des risques fournisseur et client associés. On présente aussi les mises en oeuvre de la méthode, ainsi que les résultats des différentes expérimentations en milieu industriel
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Nurit, Marvin. "numérisation et caractérisation de la réflectancelocale des surfaces complexes pour l'inspection visuelle." Electronic Thesis or Diss., Bourgogne Franche-Comté, 2022. http://www.theses.fr/2022UBFCK112.
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La maitrise de la perception visuelle des surfaces des produits manufacturés est un enjeu central pour l'industrie. Or, en entreprise, la qualité des surfaces est souvent évaluée par des contrôleur humain. Seul quelques cas spécifiques utilisent une approche instrumentale ou photométrique. Parmi les approches photométriques, l'une d'elle connaît un essor important: le Reflectance Transformation Imaging (RTI). Le RTI permet d'obtenir une estimation réduite et simplifié de la Bidirectional Reflectance Distribution Function (BRDF) et une estimation de la géométrie de la surface. Cependant cette technique présente des limites au niveau de l'acquisition et du traitement des données. L'objectif est donc de corriger certaines de ces limites afin d'améliorer le RTI et, par conséquent, le contrôle qualité visuel des états de surfaces dans l'industrie.L'une de ces limites est la grande quantité de données, complexe à analyser, obtenue avec une acquisition RTI. Nous proposons une méthodologie afin de caractériser l'apparence des surfaces à partir mesures RTI. La caractérisation des états de surface est basée sur l'utilisation de descripteurs d'apparence, statistiques et géométriques. A partir des descripteurs extraits des acquisitions RTI nous proposons une méthode afin d'estimer la saillance visuelle multi-échelle et multi-niveau en chaque pixel et permettre ainsi de discriminer les anomalies de surfaces. Une méthodologie, pour segmenter les données RTI en utilisant la saillance, est ensuite appliqué sur un cas d'application. La méthode permet de déterminer les descripteurs les plus pertinents pour la segmentation. Le calcul de distance est étendue aux acquisitions RTI afin de comparer les états de surface. Ces méthodes se basent sur la distance de Mahalanobis en utilisant les descripteurs.Une autre des limites du RTI correspond aux biais de mesure. Certains descripteurs sont invariant à ces biais de mesures sauf celui du temps d'exposition pour lequel aucun descripteurs est insensible. Nous proposons alors d'utiliser le High Dynamic Range (HDR) couplé au RTI (HD-RTI). Le couplage est fait de façon à prendre en compte les spécificité de chacune des techniques afin d'optimiser le temps d'acquisition du RTI tout en permettant la pleine mesure de la Dynamique de la scène en chaque position angulaire de la source de lumière. Avec les donnée stéréo-photométrique HD-RTI, nous pouvons reconstruire virtuellement la scène en simulant un temps d'exposition arbitraire, mais aussi, mieux caractériser et donc discriminer les anomalies de surfacesMastering the visual perception of the surfaces of manufactured products is a central issue for industry. However, in industry, the quality of surfaces is often assessed by human inspectors. Only a few specific cases use an instrumental or photometric approach. Among the photometric approaches, one of them is experiencing significant growth: Reflectance Transformation Imaging (RTI). The RTI makes it possible to obtain a reduced and simplified estimate of the Bidirectional Reflectance Distribution Function (BRDF) and an estimate of the geometry of the surface. However, this technique has limitations in terms of data acquisition and processing. The objective is therefore to correct some of these limits in order to improve the RTI and, consequently, the visual quality control of surface conditions in industry.One of these limitations is the large amount of data, complex to analyze, obtained with an RTI acquisition. We propose a methodology to characterize the appearance of surfaces from RTI measurements. The characterization of surface states is based on the use of appearance, statistical and geometric descriptors. From the descriptors extracted from the RTI acquisitions, we propose a method to estimate the multi-scale and multi-level visual salience in each pixel and thus make it possible to discriminate surface anomalies. A methodology, to segment RTI data using salience, is then applied to an application case. The method makes it possible to determine the most relevant descriptors for segmentation. Distance calculation is extended to RTI acquisitions in order to compare surface states. These methods are based on the Mahalanobis distance using the descriptors.Another limitation of RTI is measurement bias. Some descriptors are invariant to these measurement biases except that of the exposure time for which no descriptor is insensitive. We then propose to use High Dynamic Range (HDR) coupled with RTI (HD-RTI). The coupling is done in such a way as to take into account the specificities of each of the techniques in order to optimize the RTI acquisition time while allowing the full measurement of the Dynamics of the scene in each angular position of the light source. With HD-RTI stereo-photometric data, we can virtually reconstruct the scene by simulating an arbitrary exposure time, but also better characterize and therefore discriminate surface anomalies
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Megherbi, Mehdi. "Extraction et analyse de traces d'oligo- et polysaccharides - : application au contrôle qualité des miels." Lyon 1, 2006. http://www.theses.fr/2006LYO10285.
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La lutte contre la fraude dans le domaine agroalimentaire est un souci permanent pour garantir aux consommateurs des produits de qualité. La production limitée et le prix élevé du miel amènent parfois des pratiques de falsification difficiles à déceler tant au niveau de son origine (appellation) que de sa composition (par l’ajout délibéré de sirop de sucre bon marché). L’analyse des sucres, constituants majoritaires du miel, est l’une des méthodes les plus utilisées pour mettre en évidence ces techniques de fraude. Afin de rendre plus efficace les méthodes actuellement utilisées pour l’authentification et le contrôle de la qualité des miels, la recherche de nouveaux marqueurs a été entreprise par extraction sur phase solide et chromatographie des oligo- et polysaccharides. Malgré la variabilité des compositions rencontrées dans ces produits naturels, des profils chromatographiques ont permis de caractériser certaines variétés de miel et de détecter des adultérations dès l’ajout de 1 % de sirop de sucre. Cette approche amène de nouvelles solutions et perspectives pour certifier l’appellation d’un miel et contrer les techniques de falsification qui existent sur le marchéThe fight against the fraud in the agro-alimentary field is a permanent problem to warrant quality products to the consumers. The limited production and the high price of honey provoke falsification practices which are difficult to detect on its origin (appellation) and its composition (by the deliberated addition of cheap sugar syrup). The analysis of sugars, major : In order to improve the current methods for the authentification and the quality control of honeys, the search of new probes was undertaken by solid phase extraction and chromatography of oligo- and polysaccharides. In spite of the great variability of the compositions in these natural products, chromatographic fingerprints allowed to discriminate some varieties of honey and to detect adulterations from an addition of 1 % of sugar syrup. This approach leads new solutions and perspectives to certify a variety of honey and to fight against the falsification techniques which exist on the market
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Courvalin, Corinne. "Le rôle du contrôleur dans un réseau hybride à mandat public et la gestion du risque." Paris 10, 2005. http://www.theses.fr/2005PA100018.
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Cette recherche, de nature exploratoire, vise à comprendre le rôle du contrôleur et l'impact de ses décisions, au niveau de la gestion du risque, dans un réseau hybride à mandat public. Ce rôle a été appréhendé à partir de l'analyse de crises sanitaires. En final, il a été proposé un modèle exploratoire d'épidémioprévention. La méthode d'études de cas (six) a été utilisée La bibliographie a porté sur le contrôle, la règle, le risque. Les résultats ont mis en évidence des défaillances et des déviances de contrôles internes de l'entreprise non mis en évidence par les contrôles officiels. Des défaillances ont été observées au niveau du contrôle externe exercé par le contrôleur sur l'entreprise. La réglementation a été observée inéquitable, contradictoire, dérogatoire et hypertrophique. Les contrôleurs issus d'un même Corps se caractérisent par une monoculture, un corporatisme, et une situation de quasi-monopole sur le contrôle sanitaire des alimentsThis research, of exploratory nature, aims at understanding the role of the controller and the impact of his decisions, on the level of the risk management, in a hybrid network with public mandate. This role was apprehended starting from the analysis of food crises. Into final, it was proposed an exploratory model of epidemioprevention. The case-study method (six) was used. The bibliography related to control, the rule, and the risk. The results highlighted failures and internal deviances of internal control of the company, not highlighted by official controls. Failures were observed on the level of the external control exerted by the controller on the company. The regulation was observed inequitable, contradictory, derogatory and hypertrophic. The controllers resulting from the same Corps are characterized by a monoculture, a corporatism, and a situation of quasi-monopoly on the food control
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Canivet, Michel. "Inspection de défauts verriers par vision artificielle : procédés de détection et d'identification des glaçures à la bague de bouteilles en verre transparent par analyse d'images." Saint-Etienne, 1995. http://www.theses.fr/1995STET4001.
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Au cours de la production, les bouteilles en verre transparent subissent de nombreux contrôles qualité. Le but principal de ces contrôles est d'éliminer les défauts pouvant avoir de dangereuses conséquences pour le client. Les principaux défauts sont les bouillons, les trapèzes, les glaçures, les défauts dimensionnels, les glaçures à la bague sont considérées comme des défauts critiques par les verriers. Les bouteilles avec de tels défauts sont inutilisables car elles peuvent être cassées pendant ou après le conditionnement, causant des arrêts de ligne, des pertes de produit et de temps. Pour les bouteilles cylindriques, le contrôle des glaçures est en général fait par un système a camera, la bouteille étant mise en rotation. La bague est éclairée par un faisceau lumineux concentré, et lorsque le défaut passe sous la lumière, il génère une réflexion lumineuse dans l'espace, représentée par une importante variation d'intensité dans l'image. La principale difficulté d'un tel système est d'identifier le défaut sur une image dont le fond n'est pas uniforme. Le but est alors d'identifier le défaut comme un objet mobile, grâce à un algorithme basé sur l'analyse de séquences d'images. Ce genre de système présente cependant quelques inconvénients : on ne peut contrôler que les articles cylindriques. Il est difficile d'identifier le défaut sur des images bruitées. Une méthode d'inspection par translation (pas de contact sur la bouteille lors du contrôle) peut résoudre ces problèmes. Il est nécessaire pour cela de développer un système optique spécial. Cette approche nous ouvre de nouvelles voies pour le contrôle des glaçures
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Bettayeb, Belgacem. "Conception et évaluation des plans de surveillance basés sur le risque. Limitation des incertitudes qualité avec des ressources limitées de maîtrise." Phd thesis, Université de Grenoble, 2012. http://tel.archives-ouvertes.fr/tel-00859830.
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La compétitivité d'une entreprise est conditionnée par l'aptitude de son organisation de trouver des solutions pour améliorer l'efficacité de son processus de fabrication en maîtrisant sa variabilité tout en garantissant des coûts bas, des délais réduits et, parfois, une certaine capacité de produire à des grands volumes. La maîtrise du processus de fabrication est un ensemble d'activités réalisées par un processus opérationnel de contrôle en suivant un plan de surveillance préétabli avec des objectifs précis en termes de maîtrise des risques. La mise en application du plan de surveillance est souvent mise à mal par : les aléas liées aux flux physiques et informationnels, l'interaction du processus de contrôle avec d'autres processus opérationnels de l'entreprise et les limitations en ressources de maîtrise. L'objectif de cette thèse était de répondre à cette problématique en proposant des approches nouvelles pour la conception des plans de surveillance. Pour cela, nous proposons une approche assurantielle permettant de définir un plan de surveillance qui limite l'exposition aux risques et optimise l'utilisation des ressources de maîtrise. Une formalisation simplifiée a permit d'expliquer cette approche à travers des exemples. Les résultats des expérimentations sur un cas industriel, montrent l'intérêt de l'approche pour la maîtrise des risques opérationnels dans un processus de fabrication. Par la suite, une formalisation généralisée de l'approche a été proposé concevoir le plan de surveillance généralisé d'un processus disposant d'un ensemble des moyens de contrôle interposé sur plusieurs couches le long du processus qui est assujetti à multiples risques. Mots clés : Plan de surveillance, Maîtrise des risques, Allocation des inspections, Capabilité, Capacité, Performances.
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Malek, Abdel Salam. "Online fabric inspection by image processing technology." Phd thesis, Université de Haute Alsace - Mulhouse, 2012. http://tel.archives-ouvertes.fr/tel-00720041.
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The purpose of this thesis is to automate the online detection of weaving defects by a computerized system based on image processing software. Obviously, fabric inspection has an importance to prevent risk of delivering inferior quality product. Until recently, the visual defect detection is still under taken offline and manually by humans with many drawbacks such as tiredness, boredom, and, inattentiveness. Fortunately, the continuous development in computer technology introduces the online automated fabric inspection as an effective alternative. Because the defect-free fabric has a periodic regular structure, the occurrence of a defect in the fabric breaks the regular structure. Therefore, the fabric defects can be detected by monitoring fabric structure. In our work, Fast Fourier Transform and Cross-correlation techniques, i.e. linear operations, are first implemented to examine the structure regularity features of the fabric image in the frequency domain. To improve the efficiency of the technique and overcome the problem of detection errors, further thresholding operation is implemented using a level selection filter. Through this filter, the technique is able to detect only the actual or real defects and highlight their exact dimensions. A software package such as Matlab or Scilab is used for this procedure. It is implemented firstly on a simulated plain fabric to determine the most important parameters during the process of defect detection and then to optimize each of them even considering noise. To verify the success of the technique, it is implemented on real plain fabric samples with different colours containing various defects. Finally, a vision-based fabric inspection prototype that could be accomplished on-loom to inspect the fabric under construction with 100% coverage is proposed.
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Baudet, Nathalie. "Maîtrise de la qualité visuelle des produits - Formalisation du processus d'expertise et proposition d'une approche robuste de contrôle visuel humain." Phd thesis, Université de Grenoble, 2012. http://tel.archives-ouvertes.fr/tel-00807304.
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L'apparence d'un produit joue un rôle important dans la perception de sa qualité par le client. Au-delà des fonctionnalités qu'il doit remplir, un produit doit désormais avoir un aspect irréprochable. Il n'y a cependant pas de surface parfaite car, à un niveau de grossissement donné, un écart par rapport à une surface idéale peut toujours être identifié. Pour détecter cet écart et évaluer son impact sur la qualité perçue du produit, les entreprises mettent généralement en place un contrôle visuel d'aspect de surface de leurs produits. Une première thèse a été réalisée au Laboratoire SYMME afin de proposer une méthodologie permettant de réduire la variabilité généralement observée sur les résultats de ce type de contrôle. Nos travaux se situent dans la continuité de ces travaux avec l'objectif de proposer des méthodes et des outils pour la maîtrise des trois étapes d'un contrôle visuel d'aspect : exploration, évaluation et décision. Le projet de thèse réalisé dans le cadre d'un programme européen de recherche INTERREG IV réunissait différentes Universités et Entreprises. Les pratiques des entreprises partenaires ont procurés un terrain d'expérimentation des recherches proposées. Partant de cette observation, nous avons proposé une conceptualisation du contrôle visuel humain débouchant sur des propositions de méthodes et outils adaptés aux trois étapes. Ces propositions ont été testées dans les entreprises partenaires pour vérifier leur robustesse à la variété des situations industriels. Nous avons par exemple proposé un nouveau test R2&E2 Conformité qui mesure la variabilité d'un contrôle visuel et contribue à l'identification des sources possibles de cette variabilité. Outre cette conceptualisation pour la création d'outils, nous listons un ensemble de recommandations à suivre par les entreprises pour une meilleure exploration des anomalies. Nous proposons également un ensemble d'attributs sensoriels permettant de caractériser, en vue de l'évaluer, toute anomalie d'aspect. Enfin, nous montrons comment, en formalisant le processus d'expertise, un contrôleur peut évaluer une anomalie d'aspect et juger de son impact sur la qualité perçue du produit.
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Féral, François. "L'État et les fraudes commerciales." Montpellier 1, 1991. http://www.theses.fr/1991MON10034.
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Les fraudes commerciales paraissent attachées à toutes les sociétés marchandes mais leur régime social et juridique est aussi variable que complexe. Après avoir supprimé les corporations, l'administration d'État s'est engagée directement dans la répression des fraudes au début du vingtième siècle. Ces institutions pénales constituent encore aujourd'hui l'essentiel des bases de son intervention. Progressivement pourtant, on observe une modernisation et un perfectionnement de ce contrôle par une multiplication des procédures administratives. Les instances européennes ne font que renforcer ce phénomène en prolongeant et en intensifiant la maîtrise des pouvoirs publics sur le marcheCommercial fraud to be linked to merchant societies but their social and judicial system is as varied as complex. Having put an end to corporative bodies, the state administration is directly engaged in the repression of fraud at the beginning of the twentieth century. These penal institutions still constitute today the essential legal basis of its intervention. Progressively, one can notice a modernisation and an improvement of this control through a multiplication of administrative procedures. European authorities reinforce this phenomenon by extending and intensifying the control of authorities on the market
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Rezaeimalek, Mohammad. "Planification des activités d’inspection sous incertitude basée sur les conditions de maintenance préventive d’un système de production série." Thesis, Paris, ENSAM, 2019. http://www.theses.fr/2019ENAM0007.
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La planification de l'inspection de la qualité des pièces (PQIP) est un problème important dans les systèmes de production. En raison du fort impact des activités de maintenance préventive (PM) sur le taux de non-conformité des produits (un des principaux paramètres du problème PQIP), il est nécessaire de développer une planification intégrée des activités l'inspection et les activités de maintenance afin d’obtenir une optimisation globale du système. Cette thèse présente des modèles mathématiques de programmation linéaire à nombres entiers mixtes pour le problème de planification intégrée du contrôle de la qualité et des activités de gestion de maintenance dans un système de production en série à plusieurs étapes. Les modèles déterminent simultanément le moment et l’endroit optimals pour effectuer les activités susmentionnées en prenant en compte la détérioration des étapes de production. Ces deux décisions sont effectuées via la minimisation du coût total (y compris la production, la maintenance, l'inspection, la mise au rebut, la réparation et la pénalité des articles défectueux expédiés au client) et ainsi elles optimisent la productivité du système. Dans ce cas, la productivité du système est formulée comme une mesure non linéaire, puis linéarisée par la technique d'approximation linéaire par morceaux. En plus, l’incertitude relative à l’estimation des composantes de coût et de la quantité demandée est gérée par une approche possibiliste robuste. Un exemple numérique et une étude de cas réelle sont étudiés pour valider et vérifier les modèles proposés. Le résultat le plus important de cette recherche est que la détermination des lieux d’inspection le long d’un processus de fabrication à différentes périodes avec la prise en compte d’impact des activités de maintenance préventive sur le taux de production défectueuses se traduit par une amélioration significative de la performance du système de productionPart Quality Inspection Planning (PQIP) is a significant problem in multi-stage manufacturing systems. Because of an existing strong impact of Preventive Maintenance (PM) activities on the defective production rate (which is the main input of the PQIP), developing an integrated planning for the part quality inspection and PM protects system from a local optimum. This thesis presents mixed-integer linear programming models for the integrated planning problem of the part quality inspection and PM activities in a serial multi-stage manufacturing system. The models concurrently determine the right time and place for performing the above-mentioned activities while the stages are deteriorating. These two decisions are made while the models are to minimize the total cost (including the production, PM, inspection, scrap, repair, and the penalty of shipped defective items) and maximize system productivity. Notably, the system productivity is formulized as a non-linear measure, and then it is linearized by the piecewise linear approximation technique. In addition, the uncertainty about the estimation of cost components and demand is handled by a robust possibilistic approach. A numerical example and a real case study are investigated to validate and verify the proposed models. The most important result of this research is that the determination of inspection locations along a manufacturing line in different periods of time regarding the impact of preventive maintenance activities on defective production probability results in a more efficient system
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Chamla, Marie-Laure. "Les établissements pharmaceutiques de la compétence de l'Agence du médicament." Paris 5, 1994. http://www.theses.fr/1994PA05P260.
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Klankamsorn, Sirang. "Quality economics of inspection system with inspection error : simulation approach." Thesis, University of Nottingham, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.434088.
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Mehenni, B. "Fast visual inspection for quality control." Thesis, University of Nottingham, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.328421.
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Gadyuchko, Andrey, and Sören Rosenbaum. "Nondestructive quality inspection of solenoid valves." Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2016. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-200756.
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The presented innovative magnetic testing method utilises the fact, that each commercially available electromagnet can not only be used as an actuator, but also comprises internal sensor functions. This allows a huge application variety in the fields of non-destructive testing and condition monitoring of electromagnetic systems during production and within the application in the field.
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Song, Hakjoon. "PCAOB INTERNATIONAL INSPECTION AND AUDIT QUALITY." Diss., Temple University Libraries, 2012. http://cdm16002.contentdm.oclc.org/cdm/ref/collection/p245801coll10/id/175332.
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Business Administration/AccountingPh.D.
The Public Company Accounting Oversight Board (PCAOB) has recently begun inspecting foreign audit firms. An important policy concern is that several foreign jurisdictions have refused to allow the PCAOB to conduct inspections of their audit firms. In this dissertation, I investigate (1) whether audit quality is higher for client firms (henceforth "complying" clients) whose foreign auditors have been inspected by the PCAOB, compared to client firms (henceforth "blacklisted" clients) of foreign auditors whose governments have refused inspections by the PCAOB, and (2) whether audit quality improves in the post inspection period for clients of inspected foreign auditors. I use abnormal accruals, total accruals, value relevance, and the likelihood of receiving a going concern opinion as proxies for audit quality. I conduct empirical tests on two samples, a cross-sectional sample consisting of blacklisted and complying clients, and a longitudinal sample of clients of inspected foreign auditors before and after PCAOB inspections. For the going-concern models, the samples are confined to financially distressed firms, which are either clients with negative net income or negative operating cash flows or clients in the top quartile in the bankruptcy probability distribution. The cross-sectional models indicate that blacklisted clients have significantly higher abnormal and total accruals, lower value relevance and a lower likelihood of receiving a going concern opinion, than complying clients, suggesting that clients of PCAOB-inspected auditors seem to have higher audit quality. Moreover, longitudinal analyses of clients of inspected foreign auditors show that abnormal accruals and total accruals are lower after PCAOB inspections than before inspections, and value relevance is greater after inspections than before. The likelihood of receiving a going concern opinion is higher after PCAOB inspections than before inspections for one of the two distressed-firm samples. Overall, the results are generally consistent with the PCAOB's claim that the clients of foreign audit firms that have undergone PCAOB inspections have benefited from the inspections. Further analyses indicate that the benefits are concentrated in jurisdictions where the PCAOB has conducted joint inspections with local authorities, in countries where legal traditions follow common law, and for clients of Big 4 auditors.
Temple University--Theses
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Millman, Michael Peter. "Computer vision for yarn quality inspection." Thesis, Loughborough University, 2000. https://dspace.lboro.ac.uk/2134/34196.
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Structural parameters that determine yarn quality include evenness, hairiness and twist. This thesis applies machine vision techniques to yarn inspection, to determine these parameters in a non-contact manner. Due to the increased costs of such a solution over conventional sensors, the thesis takes a wide look at, and where necessary develops, the potential uses of machine vision for several key aspects of yarn inspection at both low and high speed configurations. Initially, the optimum optical / imaging conditions for yarn imaging are determined by investigating the various factors which degrade a yarn image. The depth of field requirement for imaging yarns is analysed, and various solutions are discussed critically including apodisation, wave front encoding and mechanical guidance. A solution using glass plate guides is proposed, and tested in prototype. The plates enable the correct hair lengths to be seen in the image for long hairs, and also prevent damaging effects on the hairiness definition due to yarn vibration and yarn rotation. The optical system parameters and resolution limits of the yarn image when using guide plates are derived and optimised. The thesis then looks at methods of enhancing the yarn image, using various illumination methods, and incoherent and coherent dark-field imaging.
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Condat-Ouillon, Claire. "Etude du comportement des constituants laitiers en milieu fortement sodique et de leurs interactions en filtration sur membrane : application à la régénération par filtration tangentielle des solutions alcalines de NEP de l'industrie laitière." Toulouse, INPT, 1995. http://www.theses.fr/1995INPT014G.
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Les travaux presentes concernent la faisabilite de la regeneration par technique membranaire des solutions alcalines de n. E. P. Issues de l'industrie laitiere. Nous avons aborde cette etude suivant deux axes de recherches conjoints, se rapportant a l'analyse des dispersions a filtrer et du comportement des membranes. L'analyse chimique et physico-chimique des solutions alcalines de n. E. P. Est effectuee a partir de l'etude du comportement et de l'evolution des constituants laitiers en milieu fortement sodique (2%) combine a un traitement thermique (80c). Cette etude nous a permis de mettre en evidence des modifications profondes des composes du lait et constitue un apport significatif pour une meilleure connaissance de leur comportement. Par ailleurs, les analyses realisees sur les effluents de nep montrent que les matieres a eliminer des fluides a recycler sont essentiellement presentes sous forme particulaire. Ce constat est un element favorable a l'utilisation de techniques membranaires. L'analyse du comportement des membranes et de leur colmatage est realisee a l'aide de la permporometrie gaz-liquide. Des essais preliminaires sont effectues pour determiner la dimension de pores afin d'obtenir une clarification satisfaisante. L'analyse et l'identification par porometrie des mecanismes de colmatage rencontres lors de la filtration des solutions alcalines de n. E. P. Permettent de proposer des moyens adaptes pour ameliorer les performances de la filtration et la mise en uvre industrielle de ce procede. Les essais sur installation pilote et sur site industriel valident les resultats obtenus a l'echelle du laboratoire. Ces essais mettent egalement en evidence l'interet de l'approche adoptee dans cette etude puisque nous avons pu ainsi determiner les parametres a prendre en compte pour rendre envisageable la regeneration par technique membranaire des solutions alcalines de nep dans les industries laitieres
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Taseli, Aysun. "The Effects Of Inspection Error And Rework On Quality Loss For A Nominal-the-best Type Quality Characteristic." Master's thesis, METU, 2004. http://etd.lib.metu.edu.tr/upload/12605399/index.pdf.
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Taguchi defines quality loss as the loss imposed to the consumer for each unit of deviation from the target consumer requirements. In this thesis, the effects of inspection error and rework on quality loss are studied for a nominal-the-best type quality characteristic. The distribution of the quality characteristic in a production environment where there are inspection error and a separate rework facility is investigated. 100 % inspection policy is considered. After deriving the mean and variance of the resulting distribution of the quality characteristic, the true and simulated quality loss values for a number of scenarios are calculated. Furthermore, effects of deviation of the process mean from the target and variance of the rework are studied besides inspection error and process capability through a full factor factorial experimental design. Results are discussed for possible uses as quality improvement project selection criteria.
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Kwok, Tak Lung. "Quality improvement and inspection in supply chains /." View abstract or full-text, 2004. http://library.ust.hk/cgi/db/thesis.pl?IEEM%202004%20KWOK.
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Lefley, M. "The automated inspection of knitted fabric." Thesis, De Montfort University, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.380643.
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Alexander, Adam Ross Washer Glenn A. "Guideline for implementing quality control and quality assurance for bridge inspection." Diss., Columbia, Mo. : University of Missouri--Columbia, 2009. http://hdl.handle.net/10355/6560.
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The entire thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file; a non-technical public abstract appears in the public.pdf file. Title from PDF of title page (University of Missouri--Columbia, viewed on October 13, 2009). Thesis advisor: Dr. Glenn Washer. Includes bibliographical references.
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Lindgren, Eric, and Thomas Stenberg. "Quality Inspection and Fatigue Assessment of Welded Structures." Thesis, KTH, Lättkonstruktioner, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-31700.
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Recently, Volvo Construction Equipment AB has developed a weld class system forimperfections in welded joints, which contains demands for the toe radii, cold laps, undercutsetc. and where root defects are treated as requirements on the drawing. In this master thesis, thetoe radius has been studied more carefully along with the selection of reliable measurementsystems which are able to measure the toe radius along the weld. A computerized vision systemhas been evaluated by performing a measurement system analysis. FE-simulations anddestructive fatigue testing has also been carried out to determine which radial geometry beingcritical to the fatigue life.The results show that the currently used methods and gauges do not provide the requiredaccuracy when measuring the toe radius. The gauges are handled differently by differentoperators – even when using the vision system – which makes the methods subjective andtherefore unreliable. There are measuring systems that can gather surface data along the weldwith high accuracy, but there is no reliable method to assess the data. Therefore, the authors havedeveloped an algorithm – named STELIN – that assess the gathered surface data andautomatically identifies and calculates the toe radius and the toe angle along the weld. Using thatinformation an opportunity to improve the process control when welding is possible.The performed FE-calculations show that the surface roughness in the weld toe probably has aninfluence at the fatigue life of the joint. A more precise separate study should be made todetermine the impact of the surface roughness on the fatigue life. Those results should serve as abase when reviewing the theory used when predicting the fatigue life. Currently, stress averagingapproach is used in the notches of the root and the weld toe. In the future though, there might beanother stress condition to be taken into account, if the goal of reducing weight of the finishedproduct shall be achieved. Regarding measuring the surface roughness in the weld toe, theevaluated vision system has enough accuracy to deliver reliable data.More work remains with the STELIN-algorithm. The method used when assessing the calculatedtoe radii should be based on the conclusions from the performed FE-calculations. Integrating theSTELIN-algorithm in a fast feedback measurement system – for instance, on a laser – willprobably provide good opportunities for a better process control in order to achieve higherfatigue life of the welded joint.
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Carpinetti, Luiz C. R. "Methods for computer aided inspection of geometric tolerances." Thesis, University of Warwick, 1993. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.387402.
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Hooks, Kevin. "Enhancing quality inspection through the integration of quality control and computer aided design a framework." Ohio : Ohio University, 1994. http://www.ohiolink.edu/etd/view.cgi?ohiou1177100770.
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Alcock, Robert J. "Techniques for automated visual inspection of birch wood boards." Thesis, Cardiff University, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.323153.
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Boyer, Jacob, Janos C. Keresztes, Wouter Saeys, and John Koshel. "An automated imaging BRDF polarimeter for fruit quality inspection." SPIE-INT SOC OPTICAL ENGINEERING, 2016. http://hdl.handle.net/10150/622517.
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The purpose of this project was to test and implement recent research of polarization and scatter properties that suggest using a cross polarization imaging system to reduce glare artifacts. In particular, the use of this research is to improve the machine vision of apple quality detection in the food industry. The automated measurement system was implemented by acquiring pictures at different angles and different polarization states of apples. The opto-mechanics, system integration, synchronization and data collection are controlled with LabVIEW.
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Liu, Xiaojie. "Quality Inspection of Screw Heads Using Memristor Neural Networks." OpenSIUC, 2019. https://opensiuc.lib.siu.edu/theses/2621.
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Quality inspection is an indispensable part of the production process of screws for hardware manufactories. In general, hardware manufactories do the quality test of screws by using an electric screwdriver to twist screws. However, there are some limitations and shortcomings in the manual inspection. Firstly, the efficiency of manual inspection is low. Second, manual inspection is difficult to achieve continuous working for 24 hours, which will make a high wage cost. In this thesis, in order to enhance the inspection efficiency and save test costs, we propose to use the image recognition technology of memristor neural networks to check the quality of screws. Here, we discuss different training models of neural networks, namely: convolutional neural networks, one-layer memristor neural network with fixed learning rates. By using the dataset of 8,202 screw head images, experimental results show that the classification accuracy of CNNs and memristor neural networks can achieve 96% and 90%, respectively, which prove the effectiveness of the proposed method.
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Piepmeier, Jenelle Armstrong. "Textural analysis for defect detection in automated inspection systems." Thesis, Georgia Institute of Technology, 1995. http://hdl.handle.net/1853/19108.
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Pesante-Santana, José A. "The Effects of Multitasking on Quality Inspection in Advanced Manufacturing Systems." Diss., Virginia Tech, 1997. http://hdl.handle.net/10919/29296.
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Technological and strategic developments have changed the role of human operators in the manufacturing environment. The highly specialized work force of the low-tech manufacturing system has evolved into the multi-functional work force of the high-tech manufacturing system. Among the multiple tasks that an operator is expected to conduct in advanced manufacturing systems (AMS) are job scheduling, inventory planning, machine set-up, problem solving, and quality inspection.
The quality inspection task in AMS consists of a search component, frequently conducted by a machine, and a decision making component conducted by the operator. This quality inspection system is often referred to as a hybrid inspection system (HIS). It has been demonstrated that in general the performance of HIS is better than that of pure human or pure automated inspection systems. This research investigated the effects of different types of defects (presented at the same time in the inspected parts), multitasking (concurrently conducting independent tasks), and their interaction on the operator's performance in the quality inspection task (with a memorized quality criteria) in an AMS.
The results indicate that the performance of the operator in the quality inspection task while multitasking in an AMS will be determined not only by the variety of defects that can be present in the inspected parts, but also by the mental processing resources required to meet the demand imposed by the multiple independent tasks and the memorized quality criteria. The best performance will be obtained when the additional tasks' load minimizes the monotony of the quality inspection task without interfering with the processing resources needed for the memorized quality criteria.Ph. D.
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Curram, J. B. "Computer-aided design in sampling inspection by attributes." Thesis, University of Kent, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.384480.
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Segal, Jo Ann. "The Effect of Decreasing Defect Probabilities on Quality Control Inspection." Thesis, University of North Texas, 1998. https://digital.library.unt.edu/ark:/67531/metadc278158/.
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This study was a follow up to P. C. Dams' (1996) unpublished University of North Texas masters thesis, The effect of defect probability during training on inspection accuracy in a quality control simulation. Graphics of computer circuit boards were presented in dyads with an error free sample on the left and a
comparison on the right. Comparisons had either a rotation or transposition defect, or were error free. Subjects had 10-s to accept or reject the comparison as identical to the sample. They were trained using two different stimulus fading procedures (using descending defect probabilities) and immediate feedback. Defect probabilities for the Tens were 0.60, 0.50, 0.40, and 0.30 and for the Twenties were 1.00, 0.80, 0.60, and 0.40. The last 4 pretraining and posttraining sessions were compared and the posttraining performance of the Twenties, as compared to the Tens, demonstrated greater improvement over pretraining performance. No firm conclusions could be drawn as to the effectiveness of either training procedure. The significance of the current investigation and suggestions for future research are discussed.
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Puntel, Luis. "Sampling Plan for Incoming Material Inspection at Sanden." Thesis, University of North Texas, 1995. https://digital.library.unt.edu/ark:/67531/metadc278774/.
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Sanden international, an automobile air conditioning compressor manufacturer, was facing a problem in its incoming material inspection procedures. Although the company had designed and was using its own sampling plan, some managers and supervisors where not confident of its reliability. Sanden recently established a goal for its total number of defects per supplier as one part per million. Achievement of this target required reviews of the existing sampling plan. The purpose of this project was to help Sandra identify the best alternatives for its incoming material inspection procedures. To do that considerations were made about the usefulness of sampling inspections, theoretical aspects of inspection sampling plans were examined, current sampling plans were analyzed and recommendations were made.
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Boukouvalas, Constantinos R. "Colour shade grading and its applications to visual inspection." Thesis, University of Surrey, 1996. http://epubs.surrey.ac.uk/843494/.
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This thesis is concerned with the problem of colour shade grading for Industrial Inspection and attempts to find accurate and robust solutions to this problem. The application we are interested in, is the automation of the ceramic tiles manufacturing process so as to replace the human inspectors responsible for the quality control of the product. Therefore our aim is to perform the colour grading in a way which is consistent with what the human experts and subsequently the clients would perceive. First an overview of colour vision, colour measurement and colour constancy is given. Then a method that tackles the problem of colour grading of uniform and patterned surfaces is proposed. This method is the first step towards colour grading since it involves various corrections of the data, so as to provide the necessary precision for any further attempt. The problem of colour grading of random textures is then addressed. A method based on the comparison between colour histograms is proposed, and various statistical aspects involved in the comparison of distributions such as the colour histograms are discussed. Since the real-time implementation of any industrial inspection method should be taken into account, we use a space-effective method of storing colour histograms. Having solved the problem of colour grading for the majority of uniform and textured surfaces, we then try to optimise the performance of the proposed techniques, for cases where it fails. We attribute that to the fact that every electronic sensor captures colour and patterns in a way which only approximates what the human vision system would perceive. First we propose a method of perceptual colour grading of uniform surfaces, which transforms the camera data to data as they would have been recorded by the human eye. This method makes use of metameric data, to determine the relation between the human and the electronic sensors. We use various methods of generating metamers, and we show how the need of a spectrophotometer can be overcome. In a similar way, we propose a method of perceptual colour grading of random textures, which involves the restoration of the electronically acquired data and then their transformation to a colour space which expresses the way we perceive colour texture. We test both methods with real data, and we compare them with the non-perceptual ones. All the methods proposed in this thesis have been tested with real data, from the ceramic tiles manufacturing industry, previously colour graded by human inspectors. The consistency of the methods has been tested by using various sets of all sorts of tiles, and by repeating the acquisition and grading processes many times for every set of tiles. Further, these experiments have been carried out using different apparatuses, thus allowing us to draw conclusions about their quality and to make our methods as hardware independent as possible.
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Freear, Nicholas David. "Automated visual inspection for the quality control of pad printing." Thesis, University of Birmingham, 2002. http://etheses.bham.ac.uk//id/eprint/890/.
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Pad printing is used to decorate consumer goods largely because of its unique ability to apply graphics to doubly curved surfaces. The Intelpadrint project was conceived to develop a better understanding of the process and new printing pads, inks and printers. The thesis deals primarily with the research of a printer control system including machine vision. At present printing is manually controlled. Operator knowledge was gathered for use by an expert system to control the process. A novel local corner- matching algorithm was conceived to effect image segmentation, and neuro-fuzzy techniques were used to recognise patterns in printing errors. Non-linear Finite Element Analysis of the rubber printing-pad led to a method for pre-distorting artwork so that it would print undistorted on a curved product. A flexible, more automated printer was developed that achieves a higher printing rate. Ultraviolet-cured inks with improved printability were developed. The image normalisation/ error-signalling stage in inspection was proven in isolation, as was the pattern recognition system.
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Knutson, Matthew D. "Qualification of inspection techniques for detecting leaks in pouched medical devices at Company XYZ." Online version, 2008. http://www.uwstout.edu/lib/thesis/2008/2008knutsonm.pdf.
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Lankshear, Jane F. "Quality and diversity in Anglican primary schools : a study of denominational inspection." Thesis, University of Wales Trinity Saint David, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.683378.
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Harjumaa, L. (Lasse). "Improving the software inspection process with patterns." Doctoral thesis, University of Oulu, 2005. http://urn.fi/urn:isbn:9514278941.
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Abstract
The quality of a software product depends largely on the quality of the process that is used to develop it. In small software companies, the development process may be informal or even ad hoc, which causes uncertainty and variation in the product quality. However, quality issues are as important in small companies as in their larger counterparts. To sustain their dynamics and competitiveness, small organizations need to concentrate on the most effective quality assurance methods.
Software inspection is a proven method for improving product quality and it provides a very cost-effective way for small companies to improve their development processes. This study introduces a framework for adjusting the inspection process for the organization's specific needs and evaluating its capabilities. The main focus of this work, however, is on refining and improving the inspection process. The improvement is guided by concrete instructions that are documented as process patterns. The pattern approach has already been used successfully in several other areas of software engineering. Patterns aim at capturing the best practices of software development and transferring this knowledge between people or organizations.
The framework for inspection process capability originates from the literature relating to different types of peer review methods and experiments with flexible and tool-supported inspections in small companies. Furthermore, generic process improvement models are studied to find a feasible structure for the framework. As a result of the analysis, the i3 capability model is introduced. The feasibility of the model has been investigated in real-life software organizations carrying out inspections.
After the capability evaluation, the inspection process can be upgraded with the aid of improvement patterns, which provide structured and easy-to-follow guidelines for implementing improvements. An initial list of patterns, describing solutions to the most common problems confronted in the establishment of inspections, is extracted from related inspection research and an industrial experiment.
The contributions of this study are, first, the new view of the inspection process, based on the fundamental activities that are performed during an inspection instead of a series of stages, as it is usually presented. An activity-based process description enables tailoring of the process for organization-specific needs and its targeted improvement. Second, the study introduces a practical, lightweight method for implementing the improvement. Patterns are especially suitable in companies where resources are limited and full-scale improvement programmes cannot be initiated. Furthermore, the generic process improvement models do not provide detailed information on how improvements should be carried out, and the pattern approach represents a promising method for that. Third, the inspection process currently does not have a very significant role in generic software process improvement models; this study helps in outlining the importance of inspections. A similar approach could be applied to other software subprocesses to enable their evaluation and improvement.
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Seawright, Larry L. "Reducing learning object inspection/evaluation costs in instructional design /." Diss., CLICK HERE for online access, 2003. http://contentdm.lib.byu.edu/ETD/image/etd232.pdf.
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Cockram, Trevor John. "The use of Bayesian networks to determine software inspection process efficiency." Thesis, Open University, 2001. http://oro.open.ac.uk/58170/.
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Adherence to a defined process or standards is necessary to achieve satisfactory software quality. However, in order to judge whether practices are effective at achieving the required integrity of a software product, a measurement-based approach to the correctness of the software development is required. A defined and measurable process is a requirement for producing safe software productively. In this study the contribution of quality assurance to the software development process, and in particular the contribution that software inspections make to produce satisfactory software products, is addressed. I have defined a new model of software inspection effectiveness, which uses a Bayesian Belief Network to combine both subjective and objective data to evaluate the probability of an effective software inspection. Its performance shows an improvement over the existing published models of inspection effectiveness. These previous models made questionable assumptions over the distribution of errors and were essentially static. They could not make use of experience both in terms of process improvement and the increased experience of the inspectors. A sensitivity analysis of my model showed that it is consistent with the attributes which were thought important by Michael Fagan in his research into the software inspection method. The performance of my model show that it is an improvement over published models and over a multiple logistic regression model, which was formed using the same calibration data. By applying my model of software inspection effectiveness before the inspection takes place, project managers will be able to make better use of inspection resource available. Applying the model using data collected during the inspection will help in estimation of residual errors in a product. Decisions can then be made if further investigations are required to identify errors. The modelling process has been used successfully in an industrial application.
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Snelling, Glynn. "Ofsted inspections : do they promote improvement in teaching quality?" Thesis, University of Leicester, 2002. http://hdl.handle.net/2381/31009.
Full textAbstract:
The inspection of state schools by the Office for Standards in Education (OfSTED) has been a major and very expensive national undertaking since 1992 and has had a substantial impact on the professional lives of all teachers. Although principally an exercise in accountability, this thesis investigates the other claim of OfSTED, that of improvement through inspection. The focus seeks to examine the effect of inspection on the improvement of teaching quality. The relationship between OfSTED, local education authorities, schools and individual teachers is examined, applying the Becher and Kogan model for examining structural levels within normative and operational modes. OfSTED employs a methodology increasingly under criticism from the research establishment and highlights a major difference between England and Wales and other countries. This is especially so in those states in Australia where teachers, local authorities and academic researchers work in true partnership with the central authority in the promotion of quality and school improvement. The value of inspection in improving teaching quality is demonstrated to be limited, with most teachers believing that the process has little positive impact on them professionally and many, supported by increasing research findings, believing that the process undermines teachers' professionalism and can actually lower pupils' standards of attainment. The stress created by the process is considered to be a major negative factor in the management of the nation's teachers.
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Ekstrand, Henrik. "Quality of wildlife damage field inspections and necropsy forms." Thesis, Uppsala universitet, Institutionen för biologisk grundutbildning, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-416183.
Full text
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Jin, Fenghua. "Machine vision technology for food quality and safety inspections." College Park, Md.: University of Maryland, 2008. http://hdl.handle.net/1903/8772.
Full textAbstract:
Thesis (Ph. D.) -- University of Maryland, College Park, 2008.Thesis research directed by: Fischell Dept. of Bioengineering . Title from t.p. of PDF. Includes bibliographical references. Published by UMI Dissertation Services, Ann Arbor, Mich. Also available in paper.
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Lamoreaux, Phillip T. "Does PCAOB Inspection Exposure Affect Auditor Reporting Decisions?" Diss., The University of Arizona, 2013. http://hdl.handle.net/10150/306135.
Full textAbstract:
To gain insight into the Public Company Accounting Oversight Board's (PCAOB) impact on audit quality, this study investigates the association between PCAOB inspection exposure (akin to the threat of a PCAOB inspection) and auditor reporting decisions. Certain foreign governments prohibit PCAOB inspections of their domestic auditors of U.S. SEC registrants citing sovereign control. This unique setting provides an opportunity to observe variation in the reach of the PCAOB inspection program and isolate its' effect on auditor reporting. I find that auditors in jurisdictions allowing PCAOB inspections are more likely to report going concern opinions and material weaknesses relative to auditors in jurisdictions barring PCAOB inspections. I find no difference in these auditor reporting propensities in the pre-PCAOB regulatory. This study provides evidence that PCAOB inspection exposure is associated with auditor reporting incentives, and ultimately audit quality, which is the fundamental purpose of the PCAOB inspection program.
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Zaklouta, Hadi. "Cost of quality tradeoffs in manufacturing process and inspection strategy selection." Thesis, Massachusetts Institute of Technology, 2011. http://hdl.handle.net/1721.1/76133.
Full textAbstract:
Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Materials Science and Engineering, 2011.Cataloged from PDF version of thesis.
Includes bibliographical references (p. 106-108).
In today's highly competitive markets manufacturers must provide high quality products to survive. Manufacturers can achieve higher levels of quality by changing their manufacturing process and/or by product inspection where a multitude of different strategies are often available. Each option has its own cost implications that must also be taken into account. By reconciling the competing objectives of quality maximization and cost minimization, a cost of quality approach serves as a useful framework for comparing available manufacturing process and inspection alternatives. Still, any rigorous comparison requires both a metric as well as a profound understanding of cost of quality tradeoffs. The cost of quality tradeoffs in manufacturing process and inspection strategy selection are examined through a probabilistic cost of quality model explored analytically using a sample set of fundamental inspection strategies (reinspect rejects, reinspect accepts and single inspection) and applied to the case of electric vehicle battery pack assembly. From an expected value point of view a series of parametric sensitivity analyses reveal that complex tradeoffs between manufacturing process, inspection, internal and external failure costs determine the optimal manufacturing process and inspection strategy combination. In general, reinspect rejects minimizes internal failure costs, reinspect accepts minimizes external failure costs and single inspection lies in between while minimizing inspection costs. This thesis illustrates the fact that results are scenario specific and depend on product cost-, manufacturing process and available inspection method attributes. It is also observed that manufacturing process improvement often coincides with a need to change inspection strategy choice, thereby indicating that manufacturing process and inspection strategy selection should not be performed independently of each other. This thesis demonstrates that the traditional expected value approach for evaluating cost of quality implications of manufacturing and inspection is often misleading. Decision tree formulations and discrete event simulations indicate that cost of quality distributions are asymmetric. High internal- and external failure costs, manufacturing process non-conformance rates and inspection method error rates are contributing factors. The alternative metric of expected utility captures decision makers risk aversion to high cost outliers and changes the criteria for optimality and favors inspection strategies and manufacturing processes that minimize external failure events with increasing risk intolerance. In the examined case of electric vehicle battery pack assembly both material- and external failure costs are very high. Analytical and discrete event simulation results indicate that for the given welding process the inspection strategy that minimizes external failure costs is optimal from an expected cost point of view as well as at high degrees of risk aversion. This result is shown to be sensitive to parameters driving the cost and probability of external failure events.
by Hadi Zaklouta.
S.M.
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Valieva, Inna. "Photometric Methods for Autonomous Tree Species Classification and NIR Quality Inspection." Thesis, KTH, Maskinkonstruktion (Inst.), 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-176266.
Full textAbstract:
In this paper the brief overview of methods available for individual tree stems quality evaluation and tree species classification has been performed. The use of Near Infrared photometry based on conifer’s canopy reflectance measurement in near infrared range of spectrum has been evaluated for the use in autonomous forest harvesting. Photometric method based on the image processing of the bark pattern has been proposed to perform classification between main construction timber tree species in Scandinavia: Norway spruce (Picea abies) and Scots Pine (Pinus sylvestris). Several feature extraction algorithms have been evaluated, resulting two methods selected: Statistical Analysis using gray level co-occurrence matrix and maximally stable extremal regions feature detector. Feedforward Neural Network with Backpropagation training algorithm and Support Vector Machine classifiers have been implemented and compared. The verification of the proposed algorithm has been performed by real-time testing.