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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
41

Modélisation des contrôles non-destructifs par ondes ultrasonores guidées. Application aux contrôles de canalisations / Modelling of non-destructive testing by ultrasonic guided waves : application to pipeline inspection

Bakkali, Mohammed Marouane El 28 January 2015 (has links)
La thèse s’inscrit dans les travaux du CEA LIST pour développer dans la plate-forme CIVA un module simulant le contrôle non-destructif (CND) par ondes ultrasonores guidées ; elle est dédiée au développement et à la validation de modèles simulant l’inspection de canalisations et se focalise sur le cas de canalisations comportant un ou plusieurs coudes. Pour prédire l’effet de la courbure sur les ondes guidées, une extension en coordonnées curvilignes de la méthode des éléments finis semi-analytiques est réalisée pour calculer les modes se propageant dans un coude, par résolution d’un système d’équations aux valeurs propres restreint à la section du guide. Ce développement a aidé à comprendre les effets de distorsion des champs ultrasonores et de décalage des fréquences de coupures dus à la courbure. La diffraction des ondes à la jonction entre un tube droit et un coude est ensuite calculée par raccordement modal donnant la matrice de diffraction de la jonction ; les éléments de la matrice s’obtiennent par évaluation numérique d’intégrales à la surface de la jonction. Les matrices de diffractions locales sont enfin combinées à des matrices de propagation pour rendre compte de la présence de plusieurs diffracteurs sur la canalisation, sous forme d’une matrice globale de diffraction. Le coût minimal de son calcul permet d’étudier l’influence des paramètres de contrôle et de les optimiser. Les modèles sont validés en comparant leurs prédictions avec des résultats numériques et expérimentaux de la littérature et des mesures faites au CETIM sur maquettes industrielles. Intégrés à la plate-forme CIVA, ils étendent les possibilités du module de simulation du CND par ondes guidées. / The thesis is in the framework of developments made at CEA LIST of a module of the CIVA platform to simulate nondestructive testing (NDT) by ultrasonic guided waves; it is dedicated to the development and the validation of models simulating the examination of pipelines and is focussed on the case of pipeline comprising one or several elbows. To predict effects due to the curvature on guided waves, an extension in curvilinear coordinates of the semi-analytic finite element method is worked out to compute modes propagating in an elbow, by solving an eigen system restricted to the guide section. This development allows us to better understand effects due to the curvature such as displacement field distortions or cut-off frequencies splits. The scattering of waves at the junction between a straight tube and an elbow is then computed by means of the mode-matching method, leading to the modal scattering matrix of the junction; matrix elements are obtained by numerical evaluation of integrals over the junction surface. Local scattering matrices are finally combined to propagation matrices to account for the presence of several scatterers in the pipeline, to form a global scattering matrix. Its minimal computation cost allows us to study the influence of the parameters of the testing configuration and to optimize them. Models are validated by comparing their predictions to numerical and experimental results of the literature and to measurements made at CETIM on industrial mock-ups. Integrated in the platform CIVA, the developed models extend the capabilities of the guided wave NDT module.
42

Essays on learning-by-doing after information systems implementation in developing countries: the case of Costa Rica

Wu, Tianshi 12 January 2015 (has links)
Developing countries are increasing their adoption of information systems at the country level now. One important aspect distinguishing the implementation of information systems in developing countries from that in developed countries is that developing countries usually lack the resources and capability for training and support, and the workers need to learn to use the system from their own experience. Thus, a better understanding of the workers’ learning-by-doing after the implementation of an information system in developing countries may have important theoretical and practical implications, but empirical evidence on this issue remains limited. This dissertation seeks to fill in the gap by investigating workers’ learning-by-doing after the implementation of an information system at two levels. First, it studies how an individual customs agent’ experience preparing and submitting customs documents influences her performance in document preparation and submission tasks. Second, it also examines how an agent-inspector dyad’s experience working together affects the performance of customs inspection tasks completed through the cooperation of the dyad. The first chapter provides an overview of the dissertation. The second chapter examines how the relatedness of workers’ prior experience affects their learning-by-doing and operational performance in service work. Prior research has viewed relatedness along a single dimension. However, tasks and the underlying knowledge required for task performance can vary along multiple attributes. This chapter extends prior conceptualizations of relatedness by defining it as a multi-dimensional construct and also accounting for the level of task relatedness between different categories in each task dimension. It separates the level of workers’ experience from the relatedness of their experience, and then link the two constructs to workers’ task performance, including their efficiency and quality. Analyzing data on the processing of 998,258 import customs declarations in Costa Rica from 2006-2010, the second chapter finds that customs agents, the major workers processing the customs declarations, learn from their experience to improve their time to complete the task but not their quality of completion. Moreover, it finds that the relatedness of customs agents’ experience to their current task is positively related to the quality of task completion but has a U-shape relationship with completion time, such that the completion time first decreases with and then increases with an increase in customs agents' experience relatedness. The chapter also finds that the impact of customs agents’ experience relatedness is enhanced when the agents have more experience. Overall, the results highlight the role of experience relatedness in workers’ performance in learning-by-doing service work, and help to identify ways for managers to improve different operational performance measures. Many service tasks are completed by dyads rather than by an individual worker. In this setting, the individuals in the dyad not only need to acquire knowledge about the task, but also have to learn to work with each other. Thus, individuals’ experience working together may have significant performance implications for dyads. However, this effect remains largely unexamined, especially when there are conflicts within the dyad. In the third chapter, it theorizes how a dyad’s experience working together influences the dyad’s task performance, and label it as a learning-by-working-together effect. The chapter further proposes that the impact of dyad experience can vary across tasks with different levels of complexity, goal conflict, and combinations of the two. It examines learning-by-working-together in a setting where there is goal conflict, but the dyad must work together to complete the task: customs inspections. Based on a field study on data of 323,520 customs inspections in Costa Rica, the third chapter shows that the number of prior interactions between a customs agent and a customs inspector is positively associated with the agent-inspector dyad’s efficiency in customs inspection. In addition, it demonstrates that the impact of an agent-inspector dyad’s experience working together is greater for high-complexity tasks than for low-complexity tasks, and weaker for high-conflict tasks than for low-conflict tasks. It also shows that due to a joint effect of task complexity and task-level goal conflict, dyad experience exhibits the largest impact on the performance of high-complexity, high-conflict tasks. The chapter discusses the implications of our results for the study of learning curves and for the practice.
43

Apoio ao processo de inspeção de usabilidade para aplicações de software

Santos, Fábio Henrique Oliveira dos 03 March 2011 (has links)
Made available in DSpace on 2015-04-11T14:02:40Z (GMT). No. of bitstreams: 1 fabio.pdf: 4867233 bytes, checksum: 50fd99e07e3a0dec4c10f9701864abed (MD5) Previous issue date: 2011-03-03 / Usability Inspections are methods used to verify the software s quality in relation to its interaction with users. The applications acceptability is directly related to their usability. Thus, the goal of this work is to develop ways to assist the inspection execution, providing better costeffectiveness. In this thesis, we present an assistant to support the inspection process with a focus on usability of traditional software applications and Web applications. This wizard, called APIU, aims at reducing the time spent during the inspection execution and to achieve better management of the inspection process. The wizard s requirements were defined based on practical experience in inspections and usability testing as well as studies found in current literature. This thesis presents how the proposed APIU assistant was defined and developed, the context in which it can be used, as well as studies for the improvement of the wizard. / As inspeções de usabilidade são métodos utilizados com o objetivo de verificar a qualidade de um software em relação à interação com os usuários. A aceitabilidade das aplicações está diretamente ligada à usabilidade das mesmas. Desta forma, o objetivo deste trabalho é desenvolver meios que auxiliem a execução de uma inspeção, dotando essa atividade de melhor custo-benefício. Esta dissertação propõe um assistente de apoio ao processo de inspeção de usabilidade, o APIU, voltado para aplicações de software tradicionais e aplicações Web. Este assistente de apoio objetiva reduzir o esforço gasto durante a execução de uma inspeção e apoiar um melhor gerenciamento da mesma. Este assistente teve seus requisitos definidos a partir de experiências práticas em inspeções e testes de usabilidade, além do estudo de trabalhos disponíveis na literatura. Esta dissertação apresenta como o APIU foi definido e desenvolvido, o contexto em que ele pode ser empregado e os estudos realizados para o aprimoramento do assistente.
44

Stavebně technologický projekt bytového domu v Miroslavi / Building technological project of Miroslav

Jedličková, Alena January 2018 (has links)
In this thesis there are main parts of the building and technological project of The apartment building Miroslav. There is technical report on on the technological project, studies of major technological stages, site equipment project, design of building machines and mechanisms, time plan, inspections and test plan.
45

Automated visual inspections for final assembly : A case study of cab assembly at Scania Oskarshamn / Automatiserade visuella inspektioner för slutmontering : En fallstudie på hyttmontering hos Scania i Oskarshamn

Johnson, Amos, Aronsson, Hannes January 2020 (has links)
Quality inspections have seen varying degrees of automation depending on the complexity of the task and the environment. Especially in later phases of multi-stage manufacturing processes, such as final assembly in automotive industries, quality inspections are largely manual to this day. Today, emerging technologies offer both pressures and tools to increase automation. However, the current state of the research field is lacking in studies that help guide companies toward implementation. Thus, quality managers at final assembly for Scania's truck coachwork factory in Oskarshamn (MC) stipulated a thesis assignment to explore how inspections in their final assembly workshop could be automated. This assignment constitutes the purpose of this thesis project - to provide an exploratory study into existing and emerging technologies that enable automation of quality inspections at MC. This was eventually delimited to exploring automated visual inspection technologies. In order to better understand Scania's inspection and manufacturing system, a series of interviews and shadowings were undertaken with appropriate respondents. From these, we were able to extract seven inspection system requirements, most important were the ability to (1) handle high variability, (2) add new inspections fast, (3) inspect in direct flow and (4) inspect inside and outside of the truck coach without disassembly. Then, a thorough and comprehensive review of 559 active inspections allowed us to categorize and map the nature of inspections at MC. In our literature review, a model for a general quality inspections was found, which was used to guide and ground our proposals and recommendations as well as provided intuitive illustration. Further, two paradigms emerged as most interesting for this project: machine vision and deep learning. A theoretical comparison of the two suggested that the more traditional, rule-based machine vision algorithms would struggle in accommodating the requirements previously found. However, we could infer that deep learning would be highly suitable with respect to MC's requirements and inspections. A prototype deep learning inspection system gave further validation toward our speculations that deep learning offered the greatest potential for automation in complex environments such as MC's. Although this thesis was created for Scania as a primary customer, important theoretical and practical contributions were developed for a more general audience. Firstly, the exploration into new avenues for automation that overcome their traditional limitations were provided; something that is of high current import given the trends toward more complex manufacturing settings. Practically, we provide some guidance to industries that find themselves in similar situations to Scania - employing complex manufacturing systems or having complex products - where our findings can give insights in regards to modern automation challenges and solutions. / Kvalitetsinspektioner har automatiserats i variarande grad beroende på uppgiftens och omgivningens komlexitet. I synnerhet i de senare stadierna av flerstegsproduktioner, exempelvis slutmontering i fordonstillverkningsindustrin, består manuella inspektioner i stor utsträckning. Den snabba tekniska utvecklingen som har skett nyligen avger både ett tryck och skapar verktyg för att utöka automatiseringen. Dessvärre erbjuder dagslägets forskning föga stöd till företag gällande storskalig implementering av automatiserade kvalitetsinspektionssystem. Därför skapade kvalitetschefer på Scanias lastbilshyttmonteringsfabrik i Oskarshamn (MC) ett uppdrag att utforska hur deras inspektioner skulle kunna automatiseras. Detta uppdrag utgjorde syftet i vårt examensarbete: att utföra en explorativ studie inom befintliga och nya tekniker som möjliggör automatisering av MCs kvalitetsinpspektioner, vilket senare avgränsades till undersökandet av visuella kvalitetsinspektioner. För att tillgodogöra oss en djupare förståelse för Scanias inspektions- och produktionssytem utfördes en serie intervjuer och skuggningar med kunniga respondenter. Datan som erhölls utgjorde grunden i en nulägesanalys, från vilken sju systemkrav för ett inspektionssystem på MC kunde extraheras. De viktigaste av dessa var förmågan att (1) klara av hög variation, (2) addera nya inspektionspunkter snabbt, (3) kontrollera i direktflödet och (4) kontrollera innan- och utanför lastbilshytten. Vidare gjordes en omfattande genomgång av 559 aktiva inspektionspunkter vilket resulterade i en kategorisering och kartläggning av inspektioner på MC. I vår genomgång av relevant vetenskaplig litteratur hittades en generell modell för kvalitetskontroll som användes för att illustrera och teroretiskt förankra rekommendationer för ett automatiskt inspektionssystem. Vidare urskiljdes två intressanta områden i forskningen, machine vision och deep learning. En teoretisk jämförelse av traditionella regelbaserade machine vision algoritmer med deep learning erhöll att den förstnämnda är mindre lämpad för Scania med hänsyn till de krav som tagits fram. Deep learning å andra sidan, erbjuder många fördelar i relation till dessa. Genom en relativt enkel process kunde en deep learning baserad prototyp utvecklas. Prototypen påvisade goda resultat och gav vidare validering av vår spekulation att deep learning är ett lämpligt verktyg för automatisering i komplexa miljöer.Trots att detta examensarbete hade Scania som huvudsaklig uppdragsgivare så gjordes viktiga teoretiska och praktiska bidrag. En utforskning av i nya möjligheter för automatisering som kan överkomma begränsningarna av traditionell automatisering framtogs, vilket anses som både aktuellt och av vikt för samtiden där trender går mot mer dynamiska produktionssystem. Vad gäller praktiska bidrag så utgör denna rapport en sammanställning av råd till företag som befinner sig i liknande sitser som Scania - som använder komplexa produktionssystem eller har komplexa produkter - där våra resultat kan ge insikt gällande svårigheter och lösningar för modern automatisering.
46

Výběrové prodejny s potravinářským sortimentem na obvodě Praha 1 v 80. letech 20. století / Extra choice shops with food assortment in the district of Prague 1 in the eighties of 20th century

Kiššová, Veronika January 2016 (has links)
My thesis is devoted to the influence of food retail units with an exclusive assortment on the territory of Prague 1 at the time of normalization, specifically in the 80s of the 20th century. All facilities which are mentioned in the thesis have been incorporated into the enterprise Potraviny Prague 1, and were somehow exceptional in its own way, whether it was a privilege in supplying compared to standard establishments, or the customers' demand for local delicacies. As the enterprise Potraviny Prague 1 was a direct superior of the member establishments and their important part, this thesis deals with its origin and history. Its inseparable part consists also in the mention of organized competitions, shows, and last but not least, I mention the awards, which ware granted to this enterprise. The fourth chapter focuses on the availability of the specialized range of products, their quality and the level of provided services, which is connected to overseeing the establishments by its parent organization. The methodology of this thesis uses both the scientific literature, the press of that time, and the interviews conducted using the method of oral history.
47

A multi-objective optimization framework for an inspection planning problem under uncertainty and breakdown / Un cadre d'optimisation multi-objectif pour les problèmes de planification des inspections avec prise en compte des incertitudes et défaillances

Mohammadi, Mehrdad 10 December 2015 (has links)
Dans les systèmes manufacturiers de plus en plus complexes, les variations du processus de fabrication et de ses paramètres opératoires ainsi que leurs effets sur l’ensemble du système doivent être maîtrisés, mesurés et contrôlés. Cette thèse propose un cadre d’optimisation pour l’élaboration d’un plan d’inspection optimal qui permet une prise de décision opérationnelle afin d’assurer la satisfaction des objectifs stratégiques (réduction des coûts, amélioration de la qualité, augmentation de la productivité, …). La prise de décision se divise en trois questions : Quoi contrôler ? Comment contrôler ? Quand contrôler ? Le manque d'informations fiables sur les processus de production et plusieurs facteurs environnementaux est devenu un problème important qui impose la prise en compte de certaines incertitudes lors de la planification des inspections. Cette thèse propose plusieurs formulations du problème d’optimisation de la planification du processus d'inspection, dans lesquelles, les paramètres sont incertains et les machines de production sont sujettes aux défaillances. Ce problème est formulé par des modèles de programmation mathématique avec les objectifs : minimiser le coût total de fabrication, maximiser la satisfaction du client, et minimiser le temps de la production totale. En outre, les méthodes Taguchi et Monte Carlo sont appliquées pour faire face aux incertitudes. En raison de la complexité des modèles proposés, les algorithmes de méta-heuristiques sont utilisés pour trouver les solutions optimales. / Quality inspection in multistage production systems (MPSs) has become an issue and this is because the MPS presents various possibilities for inspection. The problem of finding the best inspection plan is an “inspection planning problem”. The main simultaneous decisions in an inspection planning problem in a MPS are: 1) which quality characteristics need to be inspected, 2) what type of inspection should be performed for the selected quality characteristics, 3) where these inspections should be performed, and 4) how the inspections should be performed. In addition, lack of information about production processes and several environmental factors has become an important issue that imposes a degree of uncertainty to the inspection planning problem. This research provides an optimization framework to plan an inspection process in a MPS, wherein, input parameters are uncertain and inspection tools and production machines are subject to breakdown. This problem is formulated through several mixed-integer mathematical programming models with the objectives of minimizing total manufacturing cost, maximizing customer satisfaction, and minimizing total production time. Furthermore, Taguchi and Monte Carlo methods are applied to cope with the uncertainties. Due to the complexity of the proposed models, meta-heuristic algorithms are employed to find optimal or near-optimal solutions. Finally, this research implements the findings and methods of the inspection planning problem in another application as hub location problem. General and detail concluding remarks are provided for both inspection and hub location problems.
48

Bezpečnostní inspekce pozemních komunikací pro město Choceň / Safety inspection of roads in Choceň

Ropek, Jan January 2012 (has links)
The tendency is to create comprehensive documentation, based on the methodology for carrying out safety inspections, to serve the communications manager territory (mainly municipalities and cities) as a basis for usable implementation of proposed measures to increase safety, as well as Study for implementation of proposals contained in the projected future and implemented traffic-engineering measures on roads solved territorial unit.
49

Влияние контрольно-надзорной деятельности государства на функционирование малого и среднего бизнеса : магистерская диссертация / Influence of the state control and supervisory activities on the small and medium-sized businesses’ functioning

Лиснов, П. С., Lisnov, P. S. January 2019 (has links)
In modern conditions, from the point of view of the reform of control and supervisory activities, a comprehensive assessment of the control and supervisory measures impact on the functioning of small and medium-sized businesses becomes increasingly important. The purpose of the master's thesis is to develop a methodological approach to assessing the impact of the state control and Supervisory activities on the functioning of small and medium-sized businesses. The analysis was based on the study of scientific and periodic literature, the study of existing approaches to assessing the effectiveness and efficiency of control and supervisory activities of public authorities. Scientific and methodological publications on the research topic, normative legal acts, data of official statistics on the research subject were used as sources of information. In the course of writing a master's thesis was proposed methodological approach, involving three ways to assess the control and supervisory activities’ impact of the state on business. First, it is an analysis of the dynamics of the complex economic indicator. Secondly, the statistical study of the correlation between the indicators of control and supervisory activities and the performance of small and medium-sized businesses, the dynamics of which can be determined by the activity of control and supervisory bodies. Third, a sociological study of small and medium-sized businesses in order to obtain subjective assessments of the control and supervisory activities’ impact on their functioning. As a result of testing the proposed methodological approach, objective (economic and statistical) and subjective (sociological) assessments of the impact of state control and supervision on small and medium-sized businesses were obtained. / В современных условиях с точки зрения реформы контрольно-надзорной деятельности всю большую значимость приобретает всесторонняя оценка влияния контрольно-надзорных мероприятий на функционирования субъектов малого и среднего бизнеса. Целью магистерской диссертации является разработка методического подхода к оценке влияния контрольно-надзорной деятельности государства на функционирование малого и среднего бизнеса. Анализ основывался на изучении научно-периодической литературы, изучении существующих подходов к оценки эффективности и результативности контрольно-надзорной деятельности органов государственной власти. В качестве источников информации использовались научные и методические публикации по теме исследования, нормативно-правовые акты, данные официальной статистики по тематике исследования. В ходе написания магистерской диссертации был предложен методический подход, предполагающий три способа оценки влияния контрольно-надзорной деятельности государства на бизнес. Во-первых, это анализ динамики комплексного экономического индикатора. Во-вторых, статистическое изучение корреляционной взаимосвязи показателей контрольно-надзорной деятельности и показателей функционирования малого и среднего бизнеса, динамика которых может быть детерминирована активностью контрольно-надзорных органов. В-третьих, социологическое исследование субъектов малого и среднего бизнеса с целью получения субъективных оценок влияния контрольно-надзорной деятельности на их функционирование. В результате апробации предложенного методического подхода были получены объективные (экономико-статистические) и субъективные (социологические) оценки влияния контрольно-надзорной деятельности государства на малый и средний бизнес.
50

The King Arrives: Chinese Government Inspections and Their Effects

Xi, Jinrui 08 1900 (has links)
This dissertation studies a critical facet of Chinese politics, inspections by higher Chinese government to villages. Principally, it looks at how village economic development determines government inspection decisions and how inspections, once conducted, impact village politics. Specifically, I argue that villages perceived as destabilizing to the Chinese regime, villages with higher levels of economic inequality and villages located at the two extremes of economic development, should see more inspections. In addition, I argue that inspections, in return, drive village politics: they increase village leaders' governing efficacy and raise villagers' political awareness. This theory has received strong support from both field work and quantitative empirical tests using the Chinese Household Income Project (2002) dataset.

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