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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.
51

Sistema de gerência de pavimentos aeroportuários: estudo de caso no Aeroporto Estadual de Araraquara / Airport pavement management system: a case study in Araraquara State Airport

Jorge Braulio Cossío Durán 26 February 2015 (has links)
A presente pesquisa objetiva contribuir para a implantação de Sistemas de Gerência de Pavimentos Aeroportuários (SGPA), tendo por base um estudo de caso desenvolvido no Aeroporto Estadual de Araraquara-SP Bartolomeu de Gusmão. Foi criado um banco de dados informatizado, através do FAA PAVEAIR, programa computacional de gerência de pavimentos aeroportuários disponibilizado pelo FAA (Federal Aviation Administration), que permitiu o armazenamento de toda informação inerente aos pavimentos do complexo aeroportuário e a determinação, com base no método PCI (Pavement Condition Index), da condição atual da pista de pousos e decolagens, da pista de rolagem e do pátio de aeronaves. Os resultados mostraram que o aeroporto de Araraquara apresenta condição regular de operação, indicada por um PCI médio de 67, e que os principais defeitos encontrados foram desagregação das partículas da mistura asfáltica, trincas transversais e, principalmente, trincas longitudinais. Por conseguinte, foram planejadas intervenções de manutenção e reabilitação, de modo a evitar situações que levassem ao comprometimento geral da condição dos pavimentos e, por consequência, a um aumento significativo dos custos de conservação. A melhor estratégia, se aplicada ao longo dos vinte anos de período de projeto, resultaria em um valor de PCI médio igual a 77, correspondente a boas condições de operação. Dessa forma, o estudo de caso desenvolvido contribuiu, com um exemplo completo, para a implantação de um SGPA em nível de rede e, mais ainda, para o desenvolvimento de um SGPA integral para a rede de aeroportos de administrações aeroportuárias de pequeno, médio e grande portes no Brasil, o que deve ser precedido pela elaboração de legislação específica que exija a aplicação efetiva de técnicas de manutenção que prolonguem a vida útil dos pavimentos, especialmente devido ao aumento da demanda por transporte aéreo e à necessidade de modernas e potentes aeronaves, que requerem, cada vez mais, melhores condições funcionais e estruturais das pistas de pousos e decolagens e dos pátios de aeronaves dos aeroportos. / This research aims to contribute to the implementation of Airport Pavements Management Systems (SGPA), based on a case study developed at the Araraquara State Airport Bartolomeu de Gusmao, in the State of Sao Paulo, Brazil. A computerized database was created, using the FAA PAVEAIR, an airport pavement management computer program provided by the FAA (Federal Aviation Administration), which allowed the storage all information inherent to the airport complex facilities and determining, based on the method of PCI (Pavement Condition Index), the current condition of the runway, taxiway and apron. The results showed that the airport presents regular operating condition, indicated by an average PCI of 67, and that the main defects found were raveling, transverse cracks and mainly longitudinal cracks. Therefore, maintenance and rehabilitation operations are planned so as to avoid situations that could lead to impairment of the general condition of the pavement and, consequently, a significant increase of maintenance costs. The best strategy, if applied over the twenty-year project period, would result in average PCI value of 77, corresponding to good operating condition. Thus, the case study developed contributed with a complete example, for the implementation of a SGPA network-level and even more so for the development of a comprehensive SGPA to the airport network of administrations of small, medium and large airports in Brazil, which should be preceded by the enactment of specific legislation that requires the effective application of maintenance techniques that prolong the life of pavements, especially due to increased demand for air transport and the need for modern and powerful aircraft, requiring increasingly, better functional and structural conditions of runways and aprons.
52

Akuter ST-Strecken-Hebungsinfarkt (STEMI) bei Patientinnen und Patienten mit zusätzlich chronischem Verschluss in einem Nicht-Infarkt-Gefäß: klinische Relevanz und prognostische Bedeutung / Acute ST-segment elevation myocardial infarction (STEMI) in patients with additional chronic total occlusion (CTO) in a non-infarct-related artery: clinical relevance and prognostic significance

Scholz, Matthias 24 April 2018 (has links)
No description available.
53

Développement d'une camera x couleur ultra-rapide a pixels hybrides / Development of an ultra-fast X-ray camera using hybrid pixel detectors

Dawiec, Arkadiusz 04 May 2011 (has links)
L’objectif du projet, dont le travail présenté dans cette thèse est une partie, était de développer une caméra à rayons X ultra-rapide utilisant des pixels hybrides pour l’imagerie biomédicale et la science des matériaux. La technologie à pixels hybrides permet de répondre aux besoins des ces deux champs de recherche, en particulier en apportant la possibilité de sélectionner l’énergie des rayons X détectés et de les imager à faible dose. Dans cette thèse, nous présentons une caméra ultra-rapide basée sur l’utilisation de circuits intégrés XPAD3-S développés pour le comptage de rayons X. En collaboration avec l’ESRF et SOLEIL, le CPPM a construit trois caméras XPAD3. Deux d’entre elles sont utilisée sur les lignes de faisceau des synchrotrons SOLEIL et ESRF, et le troisième est installé dans le dispositif d’irradiation PIXSCAN II du CPPM. La caméra XPAD3 est un détecteur de rayons X de grande surface composé de huit modules de détection comprenant chacun sept circuits XPAD3-S équipés d’un système d’acquisition de données ultra-rapide. Le système de lecture de la caméra est basé sur l’interface PCI Express et sur l’utilisation de circuits programmables FPGA. La caméra permet d’obtenir jusqu’à 240 images/s, le nombre maximum d’images étant limité par la taille de la mémoire RAM du PC d’acquisition. Les performances de ce dispositif ont été caractérisées grâce à plusieurs expériences à haut débit de lecture réalisées dans le système d’irradiation PIXSCAN II. Celles-ci sont décrites dans le dernier chapitre de cette thèse. / The aim of the project, of which the work described in this thesis is part, was to design a high-speed X-ray camera using hybrid pixels applied to biomedical imaging and for material science. As a matter of fact the hybrid pixel technology meets the requirements of these two research fields, particularly by providing energy selection and low dose imaging capabilities. In this thesis, high frame rate X-ray imaging based on the XPAD3-S photons counting chip is presented. Within a collaboration between CPPM, ESRF and SOLEIL, three XPAD3 cameras were built. Two of them are being operated at the beamline of the ESRF and SOLEIL synchrotron facilities and the third one is embedded in the PIXSCAN II irradiation setup of CPPM. The XPAD3 camera is a large surface X-ray detector composed of eight detection modules of seven XPAD3-S chips each with a high-speed data acquisition system. The readout architecture of the camera is based on the PCI Express interface and on programmable FPGA chips. The camera achieves a readout speed of 240 images/s, with maximum number of images limited by the RAM memory of the acquisition PC. The performance of the device was characterize by carrying out several high speed imaging experiments using the PIXSCAN II irradiation setup described in the last chapter of this thesis.
54

Grundskollärares upplevelse av det psykologiska kontraktet och dess inverkan på intentionen att avsluta anställningen / Primary school teachers experience of the psychological contract and it’s impact on the intention to quit the employment.

Berglund, Emma, Håkansson, Andrea January 2022 (has links)
The purpose of this study was to examine how the psychological contract relates to the intention to quit the employment (ITQ) of professional primary school teachers. In addition to this, the purpose was to examine which form of contract in the psychological contract that most strongly predicts ITQ. A quantitative study was conducted, of which a digital survey was distributed via email to principals and/- or deputy principals for 312 municipal schools in Sweden and was shared on the social platform Meta as well. The survey was based on The Psychological Contract Inventory (PCI) by Rousseau and the Turnover Intention Scale - 6 items (TIS-6) by Roodt. The data collection generated 80 questionnaire responses which were then used for analysis through a hierarchical multiple regression analysis. The results showed that all four forms of contracts: transactional, relational, balanced and transitional contracts explained a larger part of the variance in ITQ. The balanced contract and the transitional contract were significant predictors of which the transactional contract and relational contract were not significant. The transitional contract predicted ITQ to the highest degree.
55

Elaboración de una base de datos aplicando la técnica del método PCI con un sistema georeferenciado para conocer el estado actual de los pavimentos del distrito de Bellavista-Sullana / Elaboration of a database applying the technique of the PCI Method with a georeferenced system to know the current state of the rigid and flexible pavements of the district of Bellavista, Sullana

Nole Dávila, Kelly Margot, Sotomayor Solano, Yordan Luis 06 April 2021 (has links)
La presente tesis tiene por finalidad elaborar una base de datos en el Software Qgis, aplicando la técnica del Método PCI con un sistema georreferenciado para conocer el estado actual de los pavimentos rígidos y flexibles del distrito de Bellavista, Sullana. En primer lugar, se zonifica el área de análisis según el tipo de pavimento que presentan las vías y se realiza la clasificación de las calles y transversales donde es aplicable el Método PCI (Pavement condition Index). Seguido de la obtención de las cantidades de unidades de muestra por secciones (avenidas, calles o transversales), para posteriormente realizar el inventario de fallas en una hoja de registro y obtener el índice de condición de las unidades de muestra, y más adelante determinar la condición de toda la calle. Con la información recolectada en campo, y después de haber realizado el levantamiento topográfico de las secciones analizadas que es determinante para elaborar la base de datos en el software, se lleva a cabo el seguimiento a las fallas para determinar sus coordenadas UTM utilizando un GPS navegador. Una vez obtenida el detalle de las fallas y sus respectivas coordenadas se procede a realizar los trabajos de gabinete donde se modela en el Software Qgis el mapa catastro y se insertan las coordenadas de cada falla evaluada. Por lo que, el estudio se centra en crear una base de datos con los índices de condición de las vías que componen el distrito de Bellavista. Finalmente, a través de la base de datos se puede generar una herramienta útil y eficaz para la Municipalidad de Bellavista, ya que actualmente no cuenta con información suficiente para realizar el control y monitoreo de los pavimentos. / The purpose of this thesis is to elaborate a database in the Qgis Software, applying the PCI Method technique with a georeferenced system to know the current state of rigid and flexible pavements in the Bellavista district, Sullana. In the first place, the analysis area is zoned according to the type of pavement that the roads present and the classification of the streets and cross-sections where the PCI Method (Pavement condition Index) is applicable is carried out. Followed by obtaining the quantities of sample units by sections (avenues, streets or cross-sections), to later carry out the inventory of failures in a record sheet and obtain the condition index of the sample units, and later determine the condition of the entire street. With the information collected in the field, and after having carried out the topographic survey of the analyzed sections, which is decisive for preparing the database in the software, the faults are tracked to determine their UTM coordinates using a GPS navigator. . Once the details of the faults and their respective coordinates have been obtained, the cabinet work is carried out where the cadastre map is modeled in the Qgis Software and the coordinates of each evaluated fault are inserted. Therefore, the study focuses on creating a database with the condition indices of the roads that make up the Bellavista district. Finally, through the database, a useful and effective tool can be generated for the Municipality of Bellavista, since it currently does not have enough information to carry out the control and monitoring of the pavements. / Tesis
56

Synthèse de EFSM observatrices à partir de spécifications HAAD

Ogoubi, Etienne January 2002 (has links)
Mémoire numérisé par la Direction des bibliothèques de l'Université de Montréal.
57

Telemetry Recorders and Disruptive Technologies

Kortick, David 10 1900 (has links)
ITC/USA 2009 Conference Proceedings / The Forty-Fifth Annual International Telemetering Conference and Technical Exhibition / October 26-29, 2009 / Riviera Hotel & Convention Center, Las Vegas, Nevada / Telemetry data recorders are not immune to the effects that a number of disruptive technologies have had on the telemetry industry. Data recorder designs today make use of data buses, storage types and graphical user interfaces that are constantly evolving based on the advances of personal computer and consumer electronics technologies. Many of these recorders use embedded designs that integrate disruptive technologies such as PCI Express for realtime data and signal processing, SATA interfaces for data storage and touchscreen technologies to provide an intuitive operator interface. Solid state drives also play a larger role in the latest recorder designs. This paper will explore the effects of these technologies on the latest telemetry recorders in terms of the benefits to the users, cost of implementation, obsolescence management, and integration considerations. The implications of early adoption of disruptive technologies will also be reviewed.
58

HARDWARE DOWNLOADABLE MULTI-FUNCTION TELEMETRY INPUT MODULE

Nicolais, Ray, Nicolo, Stephen J., Snyder, Ed 10 1900 (has links)
International Telemetering Conference Proceedings / October 23-26, 2000 / Town & Country Hotel and Conference Center, San Diego, California / This paper describes a Multi-Function Telemetry Input Module (TIM). The TIM module includes a 30 Mbps PCM frame synchronizer, a time code translator/generator, a PCM simulator and a tunable bit synchronizer all on a single PCI card. The module uses a generic architecture including: high density Field Programmable Gate Arrays (FPGAs), look-up table memory, dual port A/B data buffer memory and a full function PCI interface. The FPGA and the logic function of the card are downloadable via the PCI interface. This allows a single module to support many hardware functions in a telemetry front-end. The TIM is an integral part of a PC-based Advanced Telemetry Processing and Display System. This concept for hardware design ushers in a new generation of flexible downloadable telemetry products.
59

SIMULTANEOUS DATA PROCESSING OF MULTIPLE PCM STREAMS ON A PC BASED SYSTEM

Weisenseel, Chuck, Lane, David 10 1900 (has links)
International Telemetering Conference Proceedings / October 25-28, 1999 / Riviera Hotel and Convention Center, Las Vegas, Nevada / The trend of current data acquisition and recording systems is to capture multiple streams of Pulse Code Modulation (PCM) data on a single media. The MARS II data recording system manufactured by Datatape, the Asynchronous Realtime Multiplexer and Output Reconstructor (ARMOR) systems manufactured by Calculex, Inc., and other systems on the market today are examples of this technology. The quantity of data recorded by these systems can be impressive, and can cause difficulties in post-test data processing in terms of data storage and turn around time to the analyst. This paper describes the system currently in use at the Strategic Systems Combined Test Force B-1B division to simultaneously post-flight process up to twelve independent PCM streams at twice real-time speeds. This system is entirely personal computer (PC) based running the Window NT 4.0 operating system with an internal ISA bus PCM decommutation card. Each PC is capable of receiving and processing one stream at a time. Therefore, the core of the system is twelve PCs each with decommutation capability. All PCs are connected via a fast ethernet network hub. The data processed by this system is IRIG 106 Chapter 8 converted MIL-STD-1553B bus data and Chapter 4 Class I and II PCM data. All system operator inputs are via Distributed Component Object Modeling (DCOM) provided by Microsoft Developers Studio, Versions 5.0 and 6.0, which allows control and status of multiple data processing PCs from one workstation. All data processing software is written in-house using Visual C++ and Visual Basic.
60

Implementación de Interfaz PCI Sobre Plataforma Industrial Basada en Dispositivo FPGA

Román Asenjo, Enrique Efraín January 2009 (has links)
ISIS es una placa madre industrial desarrollada en Chile por Continental Lensa S.A orientada al soporte de SoPCs (Systems on a Programmable Chip) sobre un dispositivo FPGA (Field Programmable Gate Array), integrado con una serie de periféricos on-board. La capacidad de soportar SoPCs basados en el procesador Nios II y el sistema operativo uClinux, en conjunto con diversos núcleos de hardware de propiedad intelectual o IP cores, abre un universo de aplicaciones que abarca desde el control de sistemas, procesamiento digital de señales, y sistemas de radio y televisión digital. ISIS incorpora un conector PMC (PCI Mezzanine Card), que corresponde a una especificación mecánica para sistemas PCI de montaje paralelo y tamaño pequeño, contrario al estándar PCI convencional donde las tarjetas se montan en forma perpendicular. Sin embargo, no es posible controlar dispositivos PCI con la plataforma ISIS sin un adecuado soporte de hardware y software que provea una interfaz de bus acorde a los requerimientos del estándar PCI. El presente trabajo otorga a la plataforma ISIS soporte para conectividad con dispositivos PCI 3.3V 32 bit @ 33 MHz. El trabajo aporta la implementación de un chipset PCI embebido en el dispositivo FPGA, el soporte de software para operación con el sistema operativo uClinux, y una aplicación para control y diagnóstico del hardware. Además, se aporta un nuevo hardware que brinda una solución a la incompatibilidad entre los complejos estándares mecánicos PCI Mezzanine Card y PCI convencional de PC. Uno de los aportes es la implementación del IP core de libre distribución PCI Bridge de Opencores con interfaz de bus Wishbone, en un SoPC con arquitectura de comunicación nativa Avalon System Interconnect Fabric, lo que requiere implementar lógica de adaptación entre dos estándares de interconexión SoC incompatibles. Además, los requerimientos del sistema exigen que el IP core PCI Bridge sea implementado en modo Host, estando disponible solamente con pruebas de operación en modo Guest, lo que implica el desafío de implementar funcionalidades que no cuentan con un proceso de validación. También se desarrolla una capa de software que comunica el hardware PCI con el kernel de Linux, y un programa que permite el control y diagnóstico de los dispositivos presentes en el bus. El presente trabajo se integra como parte fundamental del equipo de radiodifusión digital de tercera generación GSD-21 Exgine. El núcleo de hardware del equipo lo constituye la plataforma ISIS integrada con el dispositivo PCI DUC-II (Next Generation Digital Up Converter), por medio de los sistemas de hardware y software desarrollados. Se obtiene una tasa de transferencia promedio de 14,5 MByte/s para transferencias PCI usando DMA, y una tasa de error de bus igual a cero para 24 horas de operación sin interrupciones del equipo GSD-21.

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