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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.
11

Trendy modernizace technologií pro řízení letů v okolí civilních letišť / Trends of modernization of the technologies intended for flight control in vicinity of an aerodrome

Buľák, Marián January 2019 (has links)
This master’s thesis deals with technologies intended for flight control during approach and landing. The main focus is on perspective approach systems, including differential technology systems. The thesis is to serve as a study aid for pilots and students of Air Traffic study programme. The main aim of this thesis is to create a qualified whole of perspective and used approach systems. Individual systems include basic characteristics and assessment of their future use. The thesis also includes an analysis of the possibility of implementing the DGNSS system at the airport with multiple runways. Prague-Ruzyně airport was chosen for this purpose. The implementation of this system is compared to other precision approach systems.
12

Technologie automatického řízení civilního letadla po trajektorii přibližování na přistání / Technology of aircraft automatic flight control along an approach trajectory

Kočiš, Martin January 2020 (has links)
This diploma thesis is focused to systems used for automatic control of civil aircraft along an precision approach trajectory. It describes precision approach systems used in the past and their evolutional steps leading to their current and future configuration. The thesis does not put the goal to be a detailed study but to be a publication providing to pilots and students of Aeronautical traffic the introduction to the field of precision approach systems in context to another fields of aeronautical traffic, describing its current status and infer its further development.
13

Testování propojení komponent systému GBAS / GBAS interconnection and testing

Polok, Zbyszek January 2016 (has links)
This thesis deals with the problem of GNSS. The document will attempt to illustrate some possible sources of error and their corrections. The main characteristics of SBAS and GBAS are described. The aim of this work is to design GBAS interconnection
14

Detection of GPS C/A Code Self-Interference: An Evaluation of Monitors

Belzer, Jessica A. January 2022 (has links)
No description available.
15

Análisis del sistema de navegación por satélite europeo EGNOS para su integración con VRS

Olivares Belinchon, Jesús Lorenzo 21 March 2016 (has links)
[EN] Abstract Global Navigation Satellite Systems (GNSS) have transformed the positioning and navigation techniques, becoming the indispensable today for multiple applications. Satellite navigation is one of the new forms of navigation and has multiple advantages over existing techniques. It can provide information to users in any location, without direct vision and comprehensively worldwide. Therefore, we are witnessing the arrival of a navigation system that, by itself, could give boaters the ability to perform positioning and route planning without the need to resort to another method or additional information. The International Civil Aviation Organization (ICAO) began in early 1990 a series of activities to define "air navigation system of the future", whose base would be the GNSS systems. The potential applicability of these systems is a reality, fulfilling the requirements of many operations navigation: accuracy, integrity, availability and continuity. One example that is already being used for CAT III operations, such as aircraft landing. The signal emitted by satellites undergoes a series of errors in its spread and the operating system to be limited for many applications. Therefore, the real-time positioning requires the use of a differential corrections to improve the performance of GNSS systems. Current differential correction systems can be grouped in local systems or LADGPS (Local Area DGPS), and extensive systems or WADGPS area (Wide Area DGPS). In March 2011 the European Commission declared the 'Safety-of-Life' service of EGNOS suitable for use in civil aviation, which is the WADGPS system used in this research together with the System of Permanent Reference Stations VRS, as system LADGPS. The objective of this thesis is the analysis of the possible integration of EGNOS navigation system with positioning methodology from ground Reference Stations Trimble VRS. It aims to improve the positioning accuracy of the EGNOS system implementing a priori more accurate VRS solution. In short, we seek a proposed methodology of positioning that has the best of both, we call EGNOS / VRS. Having defined the methodology to be used for determining the positioning EGNOS / VRS new performances are analyzed and improved accuracy is verified, allowing use is new methodology for applications with requirements for positioning accuracy, such as in agriculture precision. / [ES] Resumen Los Sistemas Globales de Navegación por Satélite (GNSS) han transformado las técnicas de posicionamiento y navegación, llegando a ser en la actualidad indispensable para múltiples aplicaciones. La navegación por satélite es una de las nuevas formas de navegación y tiene múltiples ventajas sobre las técnicas existentes. Puede proporcionar información a los usuarios en cualquier ubicación, sin necesidad de visión directa y de forma global en todo el planeta. Por tanto, estamos asistiendo a la llegada de un sistema de navegación que, por sí mismo, podría proporcionar a los navegantes la capacidad de realizar el posicionamiento y la planificación de rutas sin la necesidad de recurrir a otro método o información adicionales. La Organización de Aviación Civil Internacional (OACI) inició a principios de 1990 una serie de actividades encaminadas a definir el "sistema de navegación aérea del futuro", cuya base serían los sistemas GNSS. La aplicabilidad potencial de estos sistemas es ya una realidad, cumpliendo los requerimientos de muchas operaciones de navegación: precisión, integridad, disponibilidad y continuidad. Sirva como ejemplo que se está utilizando ya para operaciones de CAT III, como el aterrizaje de aeronaves. La señal que emiten los satélites sufre una serie de errores en su propagación y funcionamiento del sistema que los limitan para muchas aplicaciones. Por ello, el posicionamiento en tiempo real necesita de la utilización de unas correcciones diferenciales que mejoran el rendimiento de los sistemas GNSS. Los sistemas actuales de corrección diferencial los podemos agrupar en sistemas locales o LADGPS (Local Area DGPS), y sistemas de área extensa o WADGPS (Wide Area DGPS). En marzo de 2011 la Comisión Europea declaró el servicio 'Safety-of-Life' de EGNOS apto para su uso en aviación civil, siendo éste el sistema WADGPS utilizado en esta investigación junto con el sistema de Estaciones de Referencia Permanentes por VRS, como sistema LADGPS. El Objetivo de ésta Tesis es el análisis de la posible integración del sistema de navegación EGNOS con la metodología de posicionamiento a partir de Estaciones de Referencia en tierra VRS de Trimble. Se pretende mejorar la precisión de posicionamiento del sistema EGNOS implementando la solución VRS, a priori más precisa. En definitiva, buscamos una propuesta de metodología de posicionamiento que tenga lo mejor de ambas, que llamaremos EGNOS/VRS. Una vez definida la metodología a emplear para la determinación del posicionamiento EGNOS/VRS se analizan los nuevos rendimientos y se verifica la mejora de precisión, lo que permite utilizar está nueva metodología para aplicaciones con más requisitos en exactitud de posicionamiento, como por ejemplo en agricultura de precisión. / [CA] Resum Els Sistemes Globals de Navegació per Satèl¿lit (GNSS) han transformat les tècniques de posicionament i navegació, arribant a ser en l'actualitat indispensable per a múltiples aplicacions. La navegació per satèl¿lit és una de les noves formes de navegació i té múltiples avantatges sobre les tècniques existents. Pot proporcionar informació als usuaris en qualsevol ubicació, sense necessitat de visió directa i de forma global en tot el planeta. Per tant, estem assistint a l'arribada d'un sistema de navegació que, per si mateix, podria proporcionar als navegants la capacitat de realitzar el posicionament i la planificació de rutes sense la necessitat de recórrer a un altre mètode o informació addicionals. L'Organització d'Aviació Civil Internacional (OACI) va iniciar a principis de 1990 una sèrie d'activitats encaminades a definir el "sistema de navegació aèria del futur", la base del qual serien els sistemes GNSS. L'aplicabilitat potencial d'estos sistemes és ja una realitat, complint els requeriments de moltes operacions de navegació: precisió, integritat, disponibilitat i continuïtat. Servisca com a exemple que s'està utilitzant ja per a operacions de CAT III, com l'aterratge d'aeronaus. El senyal que emeten els satèl¿lits patix una sèrie d'errors en la seua propagació i funcionament del sistema que els limiten per a moltes aplicacions. Per això, el posicionament en temps real necessita de la utilització d'unes correccions diferencials que milloren el rendiment dels sistemes GNSS. Els sistemes actuals de correcció diferencial els podem agrupar en sistemes locals o LADGPS (Local Àrea DGPS) , i sistemes d'àrea extensa o WADGPS (Wide Àrea DGPS) . Al març de 2011 la Comissió Europea va declarar el servici 'Safety-of-Life' d'EGNOS apte per al seu ús en aviació civil, sent este el sistema WADGPS utilitzat en esta investigació junt amb el sistema d'Estacions de Referència Permanents per VRS, com a sistema LADGPS. L'Objectiu d'esta Tesi és l'anàlisi de la possible integració del sistema de navegació EGNOS amb la metodologia de posicionament a partir d'Estacions de Referència en terra VRS de Trimble. Es pretén millorar la precisió de posicionament del sistema EGNOS implementant la solució VRS, a priori més precisa. En definitiva, busquem una proposta de metodologia de posicionament que tinga el millor d'ambdós, que cridarem EGNOS/VRS. Una vegada definida la metodologia a emprar per a la determinació del posicionament EGNOS/VRS s'analitzen els nous rendiments i es verifica la millora de precisió, la qual cosa permet utilitzar està nova metodologia per a aplicacions amb més requisits en exactitud de posicionament, com per exemple en agricultura de precisió. / Olivares Belinchon, JL. (2016). Análisis del sistema de navegación por satélite europeo EGNOS para su integración con VRS [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/61981
16

Characterization of Airborne Antenna Group Delay as a Function of Arrival Angle and its Impact on Accuracy and Integrity of the Global Positioning System

Raghuvanshi, Anurag 01 October 2018 (has links)
No description available.
17

Influence of Nontraditional and Natural Pozzolans (NNPs) on the Mechanical and Durability Properties of Mortars and Concretes

Alberto Castillo (12323243) 29 April 2022 (has links)
<p>  </p> <p>Concrete is the second most consumed material in the world after water and is an essential element of constructed infrastructure. Over 14 billion m3 of concrete are being produced annually, resulting in a serious impact on the environment. The production of cement, which is the main component of concrete, is responsible for 5 – 8 % of global CO2 emissions. As a result, several global initiatives have been undertaken to achieve carbon neutrality by 2050. This carbon neutrality target coincides with the Paris Agreement's goal to limit global warming to 1.5 °C. A well-known, and successful strategy to reduce CO2 emissions in the concrete industry is to use supplementary cementitious materials (SCMs) as a partial replacement for cement. However, it is projected that in 2030 the demand for two of the most commonly used SCMs, fly ash and slag cement, will exceed their supply. Using nontraditional and natural pozzolans (NNPs) can help to close this supply gap, but there is a lack of knowledge regarding the reactivity and long-term performance of these materials.</p> <p>The purpose of this research was to perform experiments on several NNPs, some of which can be supplied in commercially viable quantities with the objective of evaluating their performance in cementitious systems (mortars and concretes) with the goal of accurately assessing their potential for use as alternative SCMs. The mortar study was performed using a total of 11 different NNPs, belonging to 4 distinctive groups and distributed as follows: 3 from the group of calcined clays (CCs) - CC1, CC2, and CC3, 3 from the group of natural pozzolans (NPs) - NP1, NP2 and NP3, 2 from the group of fluidized bed combustion (FBCs) ashes - FBC1 and FBC2, and 3 from the group of bottom ashes (GBAs) - GBA1, GBA2, and GBA3.</p> <p>The concrete study was performed on 4 different materials, one from each of the previously mentioned groups. The materials selected for concrete study were the worst-performing members of each group, as determined by the analysis of the test results obtained from mortars. These included CC2, NP3, FBC1, and GBA3 materials. This approach was adopted under the assumption that achieving adequate concrete characteristics with lowest-quality materials will all but assure satisfactory performance of concretes with higher-quality materials. </p> <p>The findings generated from this research indicate that several of the NNPs used in this study present a viable alternative to traditional SCMs. As an example, out of the 11 NNPS, 9 were found to conform to the requirements of the ASTM C618-19, the standard specification currently used to assess the suitability of coal fly ash and raw or calcined natural pozzolans for use in concrete. Results obtained from tests performed on mortars demonstrated that, when used at the replacement level of 25%, all 11 NNPs produced mixtures with characteristics similar to those obtained from the plain cement (OPC) mortar. For that reason, this level of replacement was selected to prepare concrete specimens. The results collected from concrete specimens showed that, when compared to plain concrete, mixtures with all 4 NNPs attained comparable (or improved) mechanical (compressive and flexural strength), durability (freeze-thaw resistance), and transport (formation factor and rate of water absorption) properties. As in the case of traditional SCMs, the mixtures with NNPs were found to require extended curing times to fully realize their property-enhancing potential associated with pozzolanic reactions. Overall, the best performing materials were those from the CCs group, followed by those belonging to, respectively, NPs, GBAs, and FBCs groups. </p>

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