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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.
811

Stavebně technologický projekt polyfunkčních domů Zlín-Příluky / Construction and technological project of multifunctional buildings in Zlín-Příluky

Kužela, Vlastimil January 2016 (has links)
This diploma thesis deals with technological project for the construction of complex of two multifunctional buildings in Zlín-Příluky. Thesis includes technical report, technological rules, plan of controls and testing, machines, safety plan, project of construction site equipment, budget and time schedule.
812

Engineering-orientierte Steuerungsarchitektur auf der Basis von Aktionsprimitiven für Anwendungen in der Robotik

Hennig, Matthias 27 August 2012 (has links)
In der vorliegenden Arbeit wird die flexible Steuerungsarchitektur Apeca für Systeme der Robotik sowie der robotergestützten Fertigungstechnik vorgestellt. Dafür werden verschiedene Anforderungen identifiziert und innerhalb eines Entwurfs vereint. Ein Hauptaugenmerk des dabei entstandenen Konzeptes ist es, einen vereinfachten Engineeringprozess für den Steuerungsentwurf zu ermöglichen. Dieser Ansatz wird durch die Verwendung von Aktionsprimitiven ermöglicht, die in Form atomarer Systemverhalten in einer speziellen Modulhierarchie eingesetzt werden. Hierzu erfolgt innerhalb der Steuerungsarchitektur eine Trennung zwischen einem funktionsorientierten verhaltensbasierten Modell zur hierarchischen sowie funktionell parallelen Ausführung von Aktionsprimitiven und einem ablauforientierten Modell zur aufgabenabhängigen Aktivierung derselben. Mit Hilfe eines Nutzerkonzepts werden diese Modelle verschiedenen Anwendern zugeordnet. Die objektorientierte Realisierung dieses Entwurfs ermöglicht die Verwendung und Synchronisation von mehreren Teilsystemen innerhalb einer Steuerung. In der Arbeit wird sowohl der entstandene Entwurf diskutiert als auch eine prototypische Implementierung vorgestellt. Abschließend werden die Ergebnisse anhand verschiedener Demonstrationsszenarien präsentiert. / In this present work, the Apeca framework, a flexible control architecture for robotic systems, is introduced. The conceptual design combines different requirements identified in miscellaneous robotic control approaches. The main focus of the resulting concept is on a simplified engineering process for the controller design. This approach is supported by the use of atomic system behaviors, the so called action primitives, in a special module hierarchy. For this purpose a distinction between a functional behavior based system model with hierarchically and also parallelly executed action primitives and a sequential control system model with a task-dependent activation of the primitives is proposed. These models are assigned to different users through a distinct user concept. An object-oriented implementation of the proposed architecture allows the utilization and synchronisation of multiple (sub-)systems within one framework. In this work the proposed framework will be discussed, a prototypical implementation will be presented and results based on different experimental scenarios will be shown.
813

Entwicklung und Gestaltung variabler Bedienelemente für ein Bedien- und Anzeigesystem im Fahrzeug

Sendler, Jochen 31 March 2008 (has links)
Angesichts der steigenden Anzahl von Funktionen in Fahrzeugen, insbesondere im Pkw, sind neue Bedien- und Anzeigesysteme notwendig, die eine optimale Bedienbarkeit der Funktionen sicherstellen und die Ablenkung des Fahrers von der Fahraufgabe minimieren. Im Rahmen dieser Arbeit wird dazu der Einsatz variabler Bedienelemente verfolgt, die sich der aktuellen Bedienaufgabe optimal anpassen. Ziel dieser Arbeit ist es insbesondere, Vorgehensweisen und Gestaltungsempfehlungen für variable Beschriftung von Tasten und zentrale Bedienelemente mit variabler Formcodierung für abgesetzte Bedien- und Anzeigesysteme zu erarbeiten. Unter Zuhilfenahme arbeitswissenschaftlicher Methoden wird dafür zunächst die Gestaltung variabler Beschriftung von Tasten untersucht und Empfehlungen für deren Gestaltung abgeleitet. Des Weiteren wird die Entwicklung eines zentralen Bedienelements mit variabler Formcodierung beschrieben. Dazu wird, aufbauend auf bekannten Entwicklungs- und Auswahlverfahren für Bedienelemente, eine Vorgehensweise zur Entwicklung variabler Bedienelemente vorgeschlagen. Das entwickelte variable zentrale Bedienelement wird darüber hinaus hinsichtlich seiner Bedienbarkeit und Ablenkungswirkung bewertet. Aus den Versuchsergebnissen konnten Gestaltungsempfehlungen abgeleitet werden, wie durch ein variables zentrales Bedienelement die Bedienbarkeit von abgesetzten Bedien- und Anzeigesystemen verbessert und die Ablenkungswirkung reduziert werden kann. Die Ergebnisse dieser Arbeit leisten einen Beitrag zur Entwicklung zukünftiger abgesetzter Bedien- und Anzeigesysteme und geben insbesondere Entwicklern und Gestaltern eine Hilfestellung beim Einsatz variabler Bedienelemente.
814

Lillgrund Wind Farm Modelling and Reactive Power Control

Boulanger, Isabelle January 2009 (has links)
The installation of wind power plant has significantly increased since several years due to the recent necessity of creating renewable and clean energy sources. Before the accomplishment of a wind power project many pre-studies are required in order to verify the possibility of integrating a wind power plant in the electrical network. The creation of models in different software and their simulation can bring the insurance of a secure operation that meets the numerous requirements imposed by the electrical system. Hence, this Master thesis work consists in the creation of a wind turbine model. This model represents the turbines installed at Lillgrund wind farm, the biggest wind power plant in Sweden. The objectives of this project are to first develop an accurate model of the wind turbines installed at Lillgrund wind farm and further to use it in different kinds of simulations. Those simulations test the wind turbine operating according to different control modes. Also, a power quality analysis is carried out studying in particular two power quality phenomena, namely, the response to voltage sags and the harmonic distortion. The model is created in the software PSCAD that enables the dynamic and static simulations of electromagnetic and electromechanical systems. The model of the wind turbine contains the electrical machine, the power electronics (converters), and the controls of the wind turbine. Especially, three different control modes, e.g., voltage control, reactive power control and power factor control, are implemented, tested and compared. The model is tested according to different cases of voltage sag and the study verifies the fault-ride through capability of the turbine. Moreover, a harmonics analysis is done. Eventually the work concludes about two power quality parameters.
815

Propuesta de mejora para la reducción de las paradas de producción en la zona de Acabados de la planta Aceros Arequipa aplicando herramientas Lean Manufacturing

Huaynalaya Eguia, Gino Renzo 23 February 2021 (has links)
El presente proyecto de mejora, se enfoca básicamente en reducir los tiempos de parada producción presentadas en la Zona de Acabados del proceso de Laminación de barras corrugadas de la corporación Aceros Arequipa. Las paradas de producción, se presentaban principalmente por fallas en el mantenimiento de máquinas y/o equipos, y por el trabamiento de barras corrugadas (varillas). Por tal motivo, se realizan propuestas de mejoras teniendo como referencia la metodología del Lean Manufacturing, de la cual se aplicaron las herramientas del TPM, Controles visuales y 5S. Para la herramienta del TPM, se utiliza los 5 pilares los cuales se relacionan con el mantenimiento de máquinas y/o equipos utilizados en el proceso; la herramienta de Controles Visuales se utiliza para reducir los tiempos perdidos en la coordinación entre operador de cabina y de campo ,y también para reducir las probabilidades de incidentes en la zona; y la herramientas de las 5S se utiliza para mejorar la limpieza en la zona, sobre todo para eliminar la cantidad de despuntes (varillas pequeñas) tiradas por la zona de trabajo. Luego de ejecutar las propuestas de mejoras a lo largo de un año, se reduce los tiempo de parada; generando un aumento de la producción diaria en 6 paquetes de varillas (15 toneladas) en el sub-proceso Zona de Acabados. Con los resultados obtenidos, se genera beneficios mensuales de 210.000 soles; además de mejoras en los Indicadores de Productividad en la empresa. / This improvement project is basically focused on reducing the production downtime presented in the Finishing Zone of the corrugated bar rolling process of the Aceros Arequipa corporation. The production stoppages were mainly due to machine and / or equipment maintenance failures, and to the locking of corrugated bars (rods). For this reason, proposals for improvements are made having as a reference the Lean Manufacturing methodology, from which the TPM, Visual Controls and 5S tools were applied. For the TPM tool, the 5 pillars are used, which are related to the maintenance of machines and / or equipment used in the process; The Visual Controls tool is used to reduce the time lost in the coordination between the cabin and field operators, and also to reduce the probability of incidents in the area; and the 5S tools are used to improve cleaning in the area, especially to eliminate the amount of spikes (small rods) thrown around the work area. After executing the improvement proposals over a year, the downtime is reduced; generating an increase in daily production in 6 packages of rods (15 tons) in the Finishing Zone sub-process. With the results obtained, monthly benefits of 210,000 soles are generated; in addition to improvements in the Productivity Indicators in the company. / Trabajo de Suficiencia Profesional
816

IFRS 15 - Den nya intäktsstandarden för avtal med kunder : Implementeringen av den nya intäktsstandarden IFRS 15

Batte, Piran, Isik, Zagros January 2021 (has links)
Title: IFRS 15- The new revenue recognition standard from contracts with customers.   Level: Student thesis, final assignment for Bachelor Degree in Business Administration    Author: Piran Batte and Zagros Isik   Supervisor: Jean-Claude Mutiganda and Pär Vilhelmson   Date: 2021 – June    Aim: The study aims to examine how listed companies in Sweden are affected by institutional pressures in the implementation of IFRS 15 and what organizational changes the revenue standard entails.    Method: The study examines listed companies in the construction and real estate industry in the Swedish market that have implemented IFRS 15 in their revenue recognition. The study is characterized by a qualitative research approach that produced data through semi-structured interviews and literary sources which were then analyzed via coding and thematic analyzes presented in tabular form.   Result & Conclusions: The results presented in the study show that the examined companies are affected by the isomorphic factors arising from the new institutional theory in the adoption and transition to IFRS 15. The companies are strongly influenced by a mandatory isomorphism as they are listed and are thus legally obliged to comply with IFRS standards. The companies are also characterized by an imitating isomorphism in the form of cooperation with competing companies because of uncertainty regarding the handling of the new standard. A normative isomorphism has been of a lesser degree. The results show no significant changes in the company's internal operations around their internal controls, IT systems and contract design, however, these have been permeated by high workload in the early phase of the implementation process of the standard. All companies felt an overestimated effect of the standard on its internal operations.    Contribution of the thesis: The study fills the existing gap around research on IFRS 15 and its impact on listed companies that are in the Swedish market. The study contributes to the new institutional theory by showing how companies experience pressure from society and norm-setting bodies. The theoretical contribution shows that mandatory and mimicking isomorphism has affected companies in the implementation of IFRS 15. Compliance with laws and advice as well as taking inspiration and collaborating with other companies have been demonstrated. The practical contribution is that companies tend to act under pressure from the environment in the goal of achieving legitimacy.   Suggestions for future research: As the companies examined in this study have been in the construction and real estate industry, a proposal for future research may be to study other listed companies that have adopted IFRS 15 as a revenue standard.    Key words: IFRS 15, Organizational Change, Implementation, New Institutional Theory, IASB, Internal Controls, IT Systems, Contract Design and Work Tasks. / Titel: IFRS 15 – Den nya intäktsstandarden för avtal med kunder   Nivå: Examensarbete på Grundnivå (kandidatexamen) i ämnet företagsekonomi    Författare: Piran Batte och Zagros Isik   Handledare: Jean-Claude Mutiganda och Pär Vilhelmson    Datum: 2021 – Juni    Syfte: Studien syftar till att undersöka hur börsnoterade företag i Sverige påverkas av institutionella påtryckningar vid implementeringen av IFRS 15 samt vilka organisationsförändringar intäktsstandarden medför.   Metod: Studien undersöker börsnoterade företag inom bygg -och fastighetsbranschen på den svenska marknaden som implementerat IFRS 15 i sin intäktsredovisning. Studien präglas av en kvalitativ forskningsansats som samlat in data genom semistrukturerade intervjuer och litterära källor som sedan analyserats via kodningar och tematiska analyser som presenterats i tabellform. Urvalet består av tio respondenter    Resultat & slutsats: Resultaten som framställs i studien visar att de undersökta företagen påverkas av de isomorfa faktorerna som härrör den ny institutionella teorin vid antagandet och övergången till IFRS 15. Företagen påverkas starkt av en tvingande isomorfism då dessa är börsnoterade och är således lagenligt skyldiga att följa IFRS-regelverken. Företagen präglas även av en härmande isomorfism i form av samarbete med konkurrerande företag till följd av ovisshet kring hanteringen av den nya standarden. En normativ isomorfism har varit av mindre grad. Resultatet visar inga påtagliga förändringar på företagens interna verksamhet kring dess interna kontroller, IT-system och kontraktsutformning dock har dessa genomsyrats av en hög arbetsbörda vid en tidig fas av implementeringsprocessen av standarden. Samtliga företag kände en överskattad effekt av standarden på dess interna verksamheter.    Examensarbetets bidrag: Studien fyller det existerande gapet kring forskning om IFRS 15 och dess påverkan på börsnoterade företag som befinner sig på den svenska marknaden. Studien bidrar till den ny institutionella teorin genom att visa hur företag påverkas av påtryckningar från samhället och normgivningsorgan. Det teoretiska bidraget visar att tvingande och härmande isomorfism har påverkat företag i implementeringen av IFRS 15. Att följa lagar och rådgivning samt att ta inspiration och samarbeta med andra företag har påvisats. Det praktiska bidraget är att företagen tenderar att agera under press från omgivningen i mål om att uppnå legitimitet.    Förslag till fortsatt forskning: Då företagen som undersökts i denna studie befunnit sig inom bygg -och fastighetsbranschen kan ett förslag till framtida forskning vara att studera andra branscher ute på börsen som antagit IFRS 15 som intäktsstandard.    Nyckelord: IFRS 15, Organisationsförändring, Implementering, New institutional theory, IASB, Interna kontroller, IT-system, Kontraktsutformning och Arbetsuppgifter
817

Risk factors associated with TB co-infection in HIV/AIDS patients taking antiretroviral therapy (ART) in one of the public health facilities in Ethiopia

Obsa Amente Megersa 24 January 2014 (has links)
Purpose: The purpose of this study is to assess risk factors associated with TB co-infection in HIV/AIDS patients taking antiretroviral therapy (ART). Methodology: An observational, analytic, case-control and quantitative study was conducted on a randomly selected 367 HIV and AIDS patients of whom 92 of them were TB co-infected. Data collection was done by using self-structured questionnaire. Result: In this study, educational status, waste disposal system, monthly income, contact history with a patient of active tuberculosis or presence of a family member with active tuberculosis, drug adherence, knowledge on tuberculosis prevention and history of exposure to substance were factors independently associated with the occurrence of active tuberculosis among HIV and Aids patients taking ART. Conclusion: The findings highlight the need for on-going educational, informational and other interventions to address the risk factors of tuberculosis in HIV and Aids patients in order to decrease the rate of TB co-infection / Health Studies / M.A. Public Health
818

Facteurs de risque professionnels des cancers des voies aérodigestives supérieures chez les femmes : analyse des données de l’étude Icare. / Occupational risk factors for head and neck cancer in French women : a population based case-control study in France, Icare

Carton, Matthieu 15 February 2017 (has links)
Contexte : Peu d’études ont recherché le rôle des facteurs de risque professionnels dans la survenue des cancers des voies aérodigestives supérieures (VADS). Ces études ont été conduites principalement chez des hommes.Objectif : L’objectif de cette thèse était d’étudier les associations entre les cancers des VADS et les expositions professionnelles chez les femmes.Méthodes : Icare est une étude cas-témoins en population générale incluant 296 cas féminins de cancers épidermoïdes des VADS et 775 femmes témoins. Les historiques de carrières recueillis ont été codés et croisés avec les matrices emplois-expositions du programme Matgéné. Outre les intitulés d’emplois, les expositions à 5 solvants chlorés (chloroforme, chlorure de méthylène, perchloréthylène, trichloréthylène, tétrachlorure de carbone), 5 solvants oxygénés (éthylène glycol, tétrahydrofurane, éther éthylique, cétones, alcools), 5 solvants pétroliers (essences carburants, essences spéciales, gazole, benzène, white-spirit) et à 7 poussières et fibres (amiante, farine, cuir, fibres céramiques réfractaires, ciment, laines minérales, silice) ont été étudiées. Les odds-ratios et leurs intervalles de confiance à 95% ajustés sur l’âge, le département, les consommations de tabac et d’alcool ont été estimés par régressions logistiques non conditionnelles.Résultats :Plusieurs professions et secteurs d’activité associés à un risque élevé de cancer des VADS ont été identifiés. Certaines professions (ouvrières de l’alimentation et des boissons, monteuses en appareillage électrique ou électronique, soudeuses) peuvent être à l’origine d’expositions professionnelles aux solvants, aux métaux, aux fumées de soudage et à diverses poussières. Les analyses par nuisance ont mis en évidence des associations significatives entre le risque de cancer des VADS et l’exposition au perchloréthylène et au au trichloréthylène. Aucune association claire n’est observée avec les solvants pétroliers et oxygénés, certains largement utilisés par les femmes L’exposition aux poussières de farine augmente significativement le risque de cancer des VADS. Une exposition probable à l’amiante est associée à une augmentation modérée et non significative du risque. Les analyses par localisation de cancer (cavité orale, pharynx, larynx), limitées par des effectifs faibles, ne mettent pas en évidence d’association spécifique.Conclusion : Nos résultats suggèrent un rôle des expositions professionnelles au trichloréthylène, au perchloréthylène et aux poussières de farine dans la survenue des cancers des VADS chez les femmes. / Background : Few occupational studies have addressed head and neck cancer, and these studies have been predominantly conducted in men. Objective : Our objective was to investigate the associations between head and neck cancer and occupational exposures in women Population and methods : ICARE, a French population-based case–control study, included 296 squamous cell carcinomas of the head and neck (HNSCC) in women and 775 female controls. Lifelong occupational history was collected. Job-exposure matrices were used to assess exposure to five chlorinated solvents (carbon tetrachloride; chloroform; methylene chloride; perchloroethylene; trichloroethylene), 5 petroleum solvents (benzene; special petroleum product; gasoline; white-spirits and other light aromatic mixtures; diesel, fuels and kerosene), 5 oxygenated solvents (alcohols; ketones and esters; ethylene glycol; diethyl ether; tetrahydrofuran) and 7 fibers and dusts (asbestos, flour dust, leather dust, refractory ceramic fibers, cement dust, mineral wools and silica) . An analysis by job title was conducted, and then associations with specific occupational exposures were investigated.Odds ratio (ORs) and 95% confidence intervals (CI), adjusted for smoking, alcohol drinking, age and residence area, were estimated with logistic models. Results : Significantly increased HNSCC risks were found for several jobs and industries. Some of these occupations (food and beverage processors, electrical and electronic equipment assemblers, welders and flame cutters) may entail exposure to agents such as solvents, metals, welding fumes and various dusts. Analyses for specific occupational exposures showed a significantly elevated risk of HNSCC associated with exposure to trichloroethylene and perchloroethylene. There is no clear evidence that petroleum or oxygenated solvents, some of them commonly used by women, are risk factors for HNSCC. Exposure to flour dust increased significantly HNSCC risk. Probable exposure to asbestos was associated with a moderate, non-significant elevation in risk. Analyses by cancer site (oral cavity, pharynx, larynx) were hampered by small numbers and did to reveal any specific association.Conclusion : These findings suggest that occupational exposure to perchloroethylene, trichloroethylene and flour dust may increase the risk of HNSCC in women.
819

Environmental Impacts Due to Fixed and Floating Offshore Wind Turbines

Brewer, Micah K 01 January 2012 (has links) (PDF)
As has been the case for onshore wind systems, the environmental effects of offshore wind farms are expected to play an important part of the development of future large-scale wind energy systems. This paper presents a detailed review of the status of, and recent developments in, research on the environmental impacts of fixed and floating offshore wind turbine systems. The primary information that has been reviewed has come from European sources where there are a significant number of offshore installations, but some work on this subject has been carried out recently in the United States. Information, from an extensive review, is presented on the environmental impacts of fixed and floating offshore wind turbines on benthic organisms, fish, marine mammals, avian species and bats. The environmental impacts of fixed and floating systems are anticipated to vary due to multiple parameters that need to be taken into account when identifying environmental impacts. Additionally, there are variations in the impact throughout the lifecycle of the offshore wind turbines. The primary focus for this paper is on the environmental impacts through the scope of barrier and habitat impacts in addition to the anticipated avian and bat fatalities. A noise propagation model is used to determine the extent of effects due to the installation of fixed and floating support structures using piling installation methods. Finally, a summary of progress in all the major environmental impact areas is given along with recommendations for future research.
820

Model-Based Approach for Resilient Vehicle Operation

Shveta Dhamankar (16709415) 31 July 2023 (has links)
<p>The vehicle industry has an endless appetite to get better. Often, this appetite is justified by the need of the hour. In the agricultural space, this translates to improving agricultural productivity in the face of population growth, reduced arable land and shortage of skilled farm labor. As for torsional vibrations, which have been around ever since the wheel was invented, the problem gets redefined with new regulations demanding new powertrains with improved fuel efficiency and reduced emissions.</p><p>A solution to the agriculture problem, involves efficiently automating the harvesting process.The first section of this thesis covers the ‘Auto-Unload’ where the goal of automation is achieved. This was done by building a simulation framework that was used to develop and synthesize the ‘AutoUnload’ controller. This controller was later deployed on a combine and a successful unloading on-the-go was demonstrated with a combine, tractor, and tractor-driven grain cart.</p><p>The solution to the second problem about drivetrain vibrations involved deriving a mathematical model for simulating the powertrain of a medium-duty truck. This was done to confirm resonance seen during testing done on a chassis dynamometer. The consequent control strategy to mitigate undesired vibration was to move the torque excitation away from the natural frequency of the system. This was achieved by a ‘gear-shifting’ algorithm. Comparison between on-road tests with and without the ‘gear-shifting’ algorithm showed that such a control strategy can effectively eliminate resonance. The solution methodology developed in this work is robust and transferable to higher engine torques and harvest speeds.</p>

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