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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.
1

The Virtuous Drone Pilot

Chapa, Joseph January 2014 (has links)
Thesis advisor: Kenneth Himes / This thesis responds to two distinct claims about drone (or remotely piloted aircraft) pilots. The first is the general claim that the martial virtues function as a kind of role morality for soldiers; the second, that drone pilots, based on the absence of personal risk and their distance from the battlefield, are unable to meet the demands of such a role morality. Chapter One explains what is meant by role morality, and determines whether the martial virtues do in fact function in a role morality capacity. The second chapter applies this general conception of a role morality for soldiers to military drone pilots in particular. This investigation finds that, insofar as "soldier" is in fact a role that generates a role morality, military drone pilots are as capable of meeting the demands of such a role morality as other military members. The second half of the thesis challenges the premise that drone pilots do not face personal risk. Chapter Three identifies psychological risk among drone pilots and seeks to determine how this kind of non-physical risk may affect the cultivation of the martial virtues. The fourth chapter argues that by placing military drone pilots within domestic territory, drone-capable militaries (such as the US military) have redrawn the battlespace such that it includes the drone operators, wherever they may be, and that as a result, drone pilots do in fact face some physical risk. Finally, in closing, this thesis presents a positive account of the martial virtues that enables military ethicists and strategists to bring centuries of philosophical investigation to bear on contemporary military issues. / Thesis (MA) — Boston College, 2014. / Submitted to: Boston College. Graduate School of Arts and Sciences. / Discipline: Philosophy.
2

Using Remotely Piloted Aircraft and Infrared Technology to Detect and Monitor Greater Sage-Grouse

Thompson, Thomas R. 01 May 2018 (has links)
In wildlife management, using cutting edge technology and science to monitor greater sage-grouse (Centrocercus urophasianus; sage-grouse) populations, enables land managers to better assess the impact of their management decisions. Having precise counts of sage-grouse lek attendance, and specifically male lek attendance, is an important metric used to evaluate population status and response to conservation actions (Gifford et.al, 2013, Dahlgren et al., 2016). Leks are seasonal breeding sites where males perform a ritualistic courtship dance for females. Our case study examined if a Remotely Piloted Aircraft (RPA) was effective in detecting, and counting, sage-grouse during the lek season (early March to late April). More specifically, this research used a Forward-Looking Infrared (FLIR) camera (a thermal camera) to detect sage-grouse and determine body temperatures of individual sage-grouse to determine if temperature data can be used to identify displaying male sage-grouse. These images can be used to document the activity and behavior of sage-grouse and can be revisited at future times to document changes in bird numbers as well as perform additional statistical analyses. We conducted 5 flights and on a per-flight basis, we identified an average of 4.4 displaying males, 13.4 non-displaying males, and 5.6 female sage-grouse. We found that the average size and average maximum temperature of the three sage-grouse categories differed where females were smaller with an average body size of 325 cm2, an average maximum temperature of 14.6 C ̊, and a smaller average thermal range of 2.47 C ̊. Non-displaying male body size was approximately 488 cm2, with a maximum average temperature of 17.2 C ̊, and an average thermal range of 4.66C ̊. Displaying male body size was the largest at approximately 655 cm2, an average maximum temperature of 27.5C ̊, with the largest average range of 12.39C ̊. Our study demonstrates that RPA and infrared technology can be used to conduct accurate sage-grouse lek attendance counts. Further, results of this study will also provide a guideline for the use of RPA’s to monitor sage-grouse and other lekking species.
3

Design and Testing of a Flight Control System for Unstable Subscale Aircraft

Sobron, Alejandro January 2015 (has links)
The primary objective of this thesis was to study, implement, and test low-cost electronic flight control systems (FCS) in remotely piloted subscale research aircraft with relaxed static longitudinal stability. Even though this implementation was carried out in small, simplified test-bed aircraft, it was designed with the aim of being installed later in more complex demonstrator aircraft such as the Generic Future Fighter concept demonstrator project. The recent boom of the unmanned aircraft market has led to the appearance of numerous electronic FCS designed for small-scale vehicles and even hobbyist-type model aircraft. Therefore, the purpose was not to develop a new FCS from scratch, but rather to take advantage of the available technology and to examine the performance of different commercial off-the-shelf (COTS) low-cost systems in statically unstable aircraft models. Two different systems were integrated, calibrated and tested: a simple, gyroscope-based, single-axis controller, and an advanced flight controller with a complete suite of sensors, including a specifically manufactured angle-of-attack transducer. A flight testing methodology and appropriate flight-test data analysis tools were also developed. The satisfactory results are discussed for different flight control laws, and the controller tuning procedure is described. On the other hand, the different test-bed aircraft were analysed from a theoretical point of view by using common aircraft-design methods and conventional preliminary-design tools. The theoretical models were integrated into a flight dynamics simulator, which was compared with flight-test data obtaining a reasonable qualitative correlation. Possible FCS modifications are discussed and some future implementations are proposed, such as the integration of the angle-of-attack in the control laws.
4

3D wind vectors measurement with remotely piloted aircraft system for aerosol-cloud interaction study

Calmer, Radiance 20 March 2018 (has links) (PDF)
The European project BACCHUS (impact of Biogenic versus Anthropogenic emissions on Clouds and Climate: towards a Holistic UnderStanding) focuses on aerosol-cloud interactions. Vertical wind velocities near cloud base, and cloud condensation nuclei (CCN) spectra, are the two most important input parameters for aerosol-cloud parcel models in determining cloud microphysical and optical properties. Therefore, the present study focuses on the instrumental development for vertical wind measurements to improve aerosol-cloud closure studies. Enhancements in Remotely Piloted Aircraft Systems (RPAS) have demonstrated their potential as tools in atmospheric research to study the boundary layer dynamics, aerosols and clouds. However, as a relatively new tool for atmospheric research, RPA require instrumental development and validation to address current observational needs. A 5-hole probe is implemented on a remotely piloted aircraft (RPA) platform, with an inertial navigation system (INS) to obtain atmospheric wind vectors. The 5- hole probe is first calibrated in a wind tunnel (at Météo-France, Toulouse, France), and an error analysis is conducted on the vertical wind measurement. Atmospheric wind vectors obtained from RPA flights are compared with wind vectors determined from sonic anemometers located at different levels on a 60 m meteorological mast (Centre de Recherches Atmosphériques, Lannemezan, France). Good agreements between vertical wind velocity probability density functions are obtained. The power spectral density of the three wind components follow the -5/3 line for the established regime of turbulence (Kolmogorov law). Turbulent kinetic energy (TKE) values calculated from the RPA are somewhat higher than TKE compared to the sonic anemometer; however, the results agree with those reported in other experiments that compare RPA platforms and sonic anemometers (Lampert et al. (2016), Båserud et al. (2016)). As the RPA equipped with a 5-hole probe (defined as the ``wind-RPA'') is developed for aerosol-cloud observations, updraft velocities near cloud base are compared with cloud radar data during a BACCHUS field campaign (Mace Head Research Station, Ireland). Three case studies illustrate the similarity of in-cloud updrafts measured between the wind-RPA and the cloud radar. A good agreement between vertical velocities of both instruments over a range of different meteorological conditions is found. Updraft velocity measurements from the wind-RPA are implemented in the aerosol-cloud parcel model to conduct a closure study for stratocumulus case with convection sampled during a BACCHUS field campaign in Cyprus. Aerosol size distributions and CCN were measured at a ground-site, which served as input to the aerosol-cloud parcel model along with the updraft velocities at cloud base measured by the RPA. In addition, the RPA conducted a vertical profile through the cloud layer and measured the shortwave transmission of solar irradiance during the ascent. The aerosol-cloud parcel model also shows that entrainment has a greater impact on cloud optical properties than variability in updraft velocity and aerosol particle concentration. Results of the case study for the Cyprus field experiment are consistent with results for similar closure studies conducted during the Mace Head field campaign (Sanchez et al., 2017), and reinforce the significance of including entrainment processes in cloud models to reduce uncertainties in aerosol-cloud interactions.
5

Measurement of aeroelastic wing deflections on a remotely piloted aircraft using modal strain shapes

Warwick, Stephen Daniel Wilfred 03 September 2020 (has links)
The aerospace industry endeavours to improve modern aircraft capabilities in efficiency, endurance, and comfort. One means of achieving these goals is through new enhancements in aerodynamics. Increased wing aspect ratio is an example of further improving efficiency. However, this comes with new challenges including possibly adverse aero-elastic and aero-servo-elastic (ASE) phenomena. New computational methods and tools are emerging and there is a need for experimental data for validation. University of Victoria’s Centre for Aerospace Research (UVic CfAR) set out to design a 20kg ASE demonstrator using a remotely piloted aircraft (RPA). This aircraft was designed with the intent of exploring coupling between aero-elastic modes including coupling between the short period aerodynamic mode and the first out-of-plane elastic mode of the wing. This thesis discuses the implementation of instrumentation designed and integrated into the ASE RPA demonstrator to monitor the deformation of the elastic wing in-flight. A strain based measurement technique was selected for integration into the ASE aircraft. This choice was made for several reasons including its reliability regardless of outdoor lighting, relatively lightweight processing requirements for real time applications, and suitable sampling bandwidth. To compute the wing deformation from strain, a method, sometimes referred to as strain pattern analysis (SPA), utilizing linear combinations of reference modal shapes fit against the measured strain, was used. Although this method is not new, to the author’s knowledge, it is the first practical application to a reduced scale RPA demonstrator. The deformation measurement system was validated against a series of distributed static load tests on the ground. Distributed load cases along the wing demonstrated good out-of-plane measurement performance. A case where only load is applied near the root of the wing resulted in the largest error in part as the mode shapes generated are less suited to approximate the resulting shape. In general errors in out-of-plane displacement at the end of the flexible wing portion can be expected to be less than 5%. The displacement at the tip of the wing can be as great as 11% for the left wing whereas the right wing is 4.7%. This suggest an asymmetry between the left and right wings requiring specifically tuned FE models for each to achieve best results. Twist angles presented in tests were relatively small for accurate comparison against the reference measurement, which was relatively noisy. Generally, the deformation measurement by SPA technique followed the same twist behaviours as the reference. A twist case, unlikely to be seen in flight, provided some insight into twist measurement robustness. The work presented is merely a small step forward with many opportunities for further research. There is room for improvement of the FE model used to generate the mode shapes in the strain pattern analysis. Initial efforts focused on the flexible spar portion of the wing. With more work improvements could be achieved for the estimation of the rigid wing. Additionally, there was some asymmetry between each wing semi-span, and with some focus on the left wing its results could be improved to at least match that of the right wing. A real-time implementation was not completed and would be particularly interesting for use as feedback for flight control. Study of load alleviation techniques may benefit. Another topic of study is the combination of this method with other measurements, such as accelerometers, to provide improved performance state estimation through sensor fusion. / Graduate
6

3D wind vectors measurement with remotely piloted aircraft system for aerosol-cloud interaction study / Mesure du vecteur tridimensionnel du vent à partir de drones pour l'étude des interactions aérosol-nuage

Calmer, Radiance 20 March 2018 (has links)
Le projet européen BACCHUS (impact of Biogenic versus Anthropogenic emissions on Clouds and Climate: towards a Holistic UnderStanding) porte sur les interactions aérosol-nuage. Les vitesses du vent vertical à proximité de la base des nuages et les spectres des noyaux de condensation des nuages (CCN) sont deux paramètres d'entrée importants pour les modèles de parcelle aérosol-nuage dans la détermination des propriétés microphysiques et optiques des nuages. Par conséquent, la présente étude se concentre sur le développement et la mise en oeuvre de mesures de vent atmosphérique afin d’améliorer les études de fermeture aérosolnuage. Les systèmes d'aéronefs pilotés à distance (RPAS) ont démontré leur potentiel en tant qu'outils pour la recherche atmosphérique dans l’étude de la couche limite, des aérosols et des nuages. Cependant, en tant qu'outil récent en recherche atmosphérique, le RPAS nécessite un développement instrumental pour répondre aux besoins d'observation actuels. Une sonde à 5 voies est développée pour une plateforme d'aéronef piloté à distance (RPA), assistée par un système de navigation inertiel (INS) pour obtenir les trois vecteurs du vent atmosphérique. La sonde à 5 voies est d'abord calibrée dans une soufflerie (à Météo-France, Toulouse, France), et une analyse d'erreur est effectuée sur la mesure du vent vertical. Les vecteurs de vent obtenus à partir de vols de RPA sont comparés à des vecteurs de vent déterminés à partir d'anémomètres soniques situés à différents niveaux d’un mât météorologique de 60 m (Centre de Recherches Atmosphériques, Lannemezan, France). Une bonne concordance entre les fonctions de densité de probabilité de la vitesse verticale du vent est obtenue. La densité spectrale de puissance des trois composantes du vent suit la ligne -5/3 en régime de turbulence établie (loi de Kolmogorov). Les valeurs d’énergie cinétique turbulente (TKE), calculées à partir du RPA, sont légèrement supérieures à celles de l'anémomètre sonique. Cependant, les résultats concordent avec ceux rapportés dans d'autres expériences comparant les plateformes RPAs à des anémomètres soniques (Lampert et al. (2016), Båserud et al. (2016)). Comme le RPA équipé d'une sonde à 5 voies (définie comme le ``wind-RPA'') est développé pour les observations aérosol-nuage, les vitesses verticales (updraft) près de la base des nuages sont comparées avec les données d’un radar de nuage au cours d'une campagne de mesures BACCHUS (Mace Head Research Station, Irlande). Trois études de cas illustrent la similitude des vitesses verticales dans les nuages mesurées par le wind-RPA et le radar de nuage. Une bonne concordance entre les vitesses verticales des deux instruments à travers différentes conditions météorologiques est établie. Les mesures de vitesse verticale du wind-RPA sont implémentées dans le modèle de parcelle aérosol nuage pour mener une étude de fermeture (campagne de mesures BACCHUS à Chypre). Les distributions de taille des aérosols et les CCN mesurés par un site au sol servent de paramètres d’entrée au modèle avec les vitesses verticales mesurées par le RPA. Le modèle de parcelle aérosol-nuage montre que l'entraînement dans les nuages a un impact plus important sur les propriétés optiques des nuages que la variabilité de la vitesse verticale et que la concentration en aérosols. Les résultats du cas d’étude de Chypre sont cohérents avec les résultats des études de fermeture similaires de la campagne de mesures à Mace Head (Sanchez et al., 2017) et renforcent l'importance d'inclure les processus d'entraînement dans les modèles de nuages pour réduire les incertitudes liées aux interactions aérosol-nuage. / The European project BACCHUS (impact of Biogenic versus Anthropogenic emissions on Clouds and Climate: towards a Holistic UnderStanding) focuses on aerosol-cloud interactions. Vertical wind velocities near cloud base, and cloud condensation nuclei (CCN) spectra, are the two most important input parameters for aerosol-cloud parcel models in determining cloud microphysical and optical properties. Therefore, the present study focuses on the instrumental development for vertical wind measurements to improve aerosol-cloud closure studies. Enhancements in Remotely Piloted Aircraft Systems (RPAS) have demonstrated their potential as tools in atmospheric research to study the boundary layer dynamics, aerosols and clouds. However, as a relatively new tool for atmospheric research, RPA require instrumental development and validation to address current observational needs. A 5-hole probe is implemented on a remotely piloted aircraft (RPA) platform, with an inertial navigation system (INS) to obtain atmospheric wind vectors. The 5- hole probe is first calibrated in a wind tunnel (at Météo-France, Toulouse, France), and an error analysis is conducted on the vertical wind measurement. Atmospheric wind vectors obtained from RPA flights are compared with wind vectors determined from sonic anemometers located at different levels on a 60 m meteorological mast (Centre de Recherches Atmosphériques, Lannemezan, France). Good agreements between vertical wind velocity probability density functions are obtained. The power spectral density of the three wind components follow the -5/3 line for the established regime of turbulence (Kolmogorov law). Turbulent kinetic energy (TKE) values calculated from the RPA are somewhat higher than TKE compared to the sonic anemometer; however, the results agree with those reported in other experiments that compare RPA platforms and sonic anemometers (Lampert et al. (2016), Båserud et al. (2016)). As the RPA equipped with a 5-hole probe (defined as the ``wind-RPA'') is developed for aerosol-cloud observations, updraft velocities near cloud base are compared with cloud radar data during a BACCHUS field campaign (Mace Head Research Station, Ireland). Three case studies illustrate the similarity of in-cloud updrafts measured between the wind-RPA and the cloud radar. A good agreement between vertical velocities of both instruments over a range of different meteorological conditions is found. Updraft velocity measurements from the wind-RPA are implemented in the aerosol-cloud parcel model to conduct a closure study for stratocumulus case with convection sampled during a BACCHUS field campaign in Cyprus. Aerosol size distributions and CCN were measured at a ground-site, which served as input to the aerosol-cloud parcel model along with the updraft velocities at cloud base measured by the RPA. In addition, the RPA conducted a vertical profile through the cloud layer and measured the shortwave transmission of solar irradiance during the ascent. The aerosol-cloud parcel model also shows that entrainment has a greater impact on cloud optical properties than variability in updraft velocity and aerosol particle concentration. Results of the case study for the Cyprus field experiment are consistent with results for similar closure studies conducted during the Mace Head field campaign (Sanchez et al., 2017), and reinforce the significance of including entrainment processes in cloud models to reduce uncertainties in aerosol-cloud interactions.
7

MINERAÇÃO DE DADOS DE IMAGENS OBTIDAS COM AERONAVE REMOTAMENTE PILOTADA PARA ESTIMATIVA DE PRODUTIVIDADE DO TRIGO

Gerke, Tiago 03 February 2017 (has links)
Made available in DSpace on 2017-07-21T14:19:29Z (GMT). No. of bitstreams: 1 TIAGO GERKE.pdf: 2494737 bytes, checksum: 62b5d2787dcdebe0e9ccf39bfa75f626 (MD5) Previous issue date: 2017-02-03 / Wheat cultivation plays an important role to Brazil and the world economic development, as well as in the human diet. The wheat Brazilian production is insufficient to meet the national demand, making research needed in order to improve the yield of this cereal. The goal of this work was to estimate wheat yield, searching for a predictive model through the data mining techniques, with data obtained from high spatial resolution images collected by unmanned aerial vehicles (UAV). The work was carried out in two experimental areas at Ponta Grossa city, Parana state, where for each area eight images were taken, at different culture development stages, with spatial resolution of 3.4cm/px and two images with resolution 10cm/px and 20cm/px, using an eBee UAV with an RGB and a NIR camera. The image processing was done with the Pix4D software, and resulted in an orthomosaics with reflectance values at different wavelengths: Red, Green and Blue, from the RGB camera and Red, Greed and NIR from the NIR camera, besides an image with NDVI values obtained from the arithmetic of NIR and Red wavelengths. The georeferencing correction of each orthomosaic and the extraction of the reflectance values were done with Quantum GIS geographic information system (GIS). From the extracted reflectance values, databases in different proportions (10%, 20%, 40%, 70% and 100%) were created for data mining, using the SMOReg algorithm, based on a support vector machine (SVM) for regression (SVR). The georreferencing correction using 10 control points provided ortomosaics with mean square error (RSME) of distance of 0.35m, which did not show significant difference compared to the correction with 5 control points (RMSE = 0.38m). The reflectance values were different for each study area, making it difficult to indicate better periods for estimating wheat yield. The highest correlation were obtained with data from RGB camera images, followed by the NIR and NDVI camera, with correlations of 0.6168,0.5423 and 0.5324, respectively. The amount of information extracted from the images, reflected in the proportion of the databases, was not significant to generated predictive models, as well as in the correlation indexes, which were statistically the same. Better correlation indices were obtained from the data extracted from the images with spatial resolution of 20cm/px, which suggests that high spatial resolution images may not be adequate for wheat yield estimation. / O cultivo do trigo desempenha um papel importante no desenvolvimento econômico de várias regiões do Brasil e do mundo, bem como na dieta humana. A produção brasileira do trigo é insuficiente para atender à demanda nacional, tornando necessárias pesquisas com intuito de melhorar a produtividade desse cereal. O objetivo desse trabalho foi a estimativa de produtividade do trigo, a partir da criação de modelos preditivos por meio da mineração de dados obtidos em imagens de alta resolução espacial, coletadas por aeronave remotamente pilotada (RPA). O trabalho foi realizado em duas áreas experimentais na cidade de Ponta Grossa – PR, onde para cada área foram feitas oito coletas de imagens, em diferentes estádios de desenvolvimento da cultura, com resolução espacial de 3,4cm/px e duas coletas com resolução 10cm/px e 20cm/px, através de uma RPA eBee utilizando uma câmera RGB e outra NIR. O processamento das imagens foi feito a partir do software Pix4D, e resultou em um ortomosaicos com os valores de refletância em diferentes comprimentos de onda: R, G e B da câmera RGB e R, G e NIR da câmera NIR, além de uma imagem com valores de NDVI obtidos a partir da aritmética das bandas Nir e Red (vermelho). A correção de georreferenciamento de cada ortomosaico e a extração dos valores de refletância foram feitas com auxílio do sistema de informação geográfica (SIG) Quantum GIS. A partir dos valores de refletância extraídos, foram criadas bases de dados em diferentes proporções (10%, 20%, 40%, 70% e 100%) para mineração de dados por meio do algoritmo SMOReg, baseado em máquina de vetor de suporte (SVM) para regressão (SVR). A correção de georreferenciamento utilizando 10 pontos de controle proporcionou ortomosaicos com erro médio quadrático (RSME) de distância de 0,35m, o qual não mostrou diferença significativa para a correção com 5 pontos de controle (RMSE = 0,38m). Os valores de refletância foram diferentes para cada área de estudo, tornando difícil a indicação de melhores períodos para a estimativa de produtividade do trigo. Os maiores índices de correlação da produtividade com os comprimentos de onda, foram obtidos com os dados das imagens da câmera RGB, seguido da câmera NIR e NDVI, com as correlações de 0,6168, 0,5423 e 0,5324, respectivamente. A quantidade de informação extraída das imagens, refletida na proporção das bases de dados, não se mostrou significativa nos modelos preditivos gerados, bem como nos índices de correlação, os quais foram estatisticamente iguais. Índices de correlação melhores foram obtidos a partir dos dados extraídos das imagens com resolução espacial de 20cm/px, o que sugere que imagens de alta resolução espacial podem não ser adequadas para estimativa de produtividade do trigo.
8

Índice de vegetação por diferença normalizada (NDVI) para definição de zonas de manejo e monitoramento da variabilidade da sucessão aveia preta/soja / Normalized differential vegetation index (NDVI) for the definition of management zone and monitoring of variability of succession black oats / soybean

Damian, Júnior Melo 18 January 2017 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / The no-tillage system (SPD) was one of the main innovations in Brazilian agriculture, but there are still discussions about how to achieve and maintain its quality and sustainability. The management of SPD areas through management zones presents great potential for this purpose, since it integrates different variables in order to facilitate and increase the technical and computerized management of agricultural practices and consequently the reduction of polluting potencies in environments. Among the main variables used to delimit management zones are the chemical attributes, yield maps and recently the NDVI index. In this sense, with Article I, the objective was to delimit management zones through yield maps and NDVIs derived from satellite images in historical series. To do this, in an area of 118 ha, three yield maps of different cultures between the years of 2010 to 2015 were selected and for each yield map we searched for the images from the Landsat 5 and 8 satellite that included a date in of the cycle of the crop in question from which the NDVI was calculated and also with the intention of verifying the stability of the NDVI generated in different crop cycles, four other satellite images were selected for four crops according to the historical of the study area, between the years 2007 and 2013. In article II, the objective was to verify the variability caused by the winter cover crop in the summer crop and if the NDVI index performed by land and with a RPAS is able to evidence this variability in the summer crop. In an area 73.96 there was applied a sampling grid of 70.71 x 70.71 m (0.5 ha), where soil sampling for chemical analysis and dry matter nutrients accumulated in the winter cover crop of black oats where soybean was sown in the summer, in which in the R5 and R5.5 stages evaluations were carried out with a portable sensor "by land" and with a RPAS for obtaining of the NDVI index and finally the grain yield of the soybean was determined, as well as the final population of plants. With the results, NDVI from satellite images can replace and/or compose the yield maps (article I) and that the dry mass and accumulated nutrients in the winter crop interfere with the yield of the summer crop and the NDVI index performed by land or with a RPAS was effective in expressing this variability (article II). / O Sistema Plantio Direto (SPD) foi uma das principais inovações na agricultura brasileira, contudo ainda há discussões sobre como alcançar e manter sua qualidade e sustentabilidade. A gestão de áreas sob SPD por meio de zonas de manejo, apresenta grande potencial para essa finalidade, pois integra diferentes variáveis afim de facilitar e incrementar a gestão tecnificada e informatizada das práticas agrícolas, e em consequência a redução de potencias poluidores no ambiente. Entre as principais variáveis utilizadas para delimitar zonas de manejo estão os atributos químicos, mapas de rendimento e recentemente o índice NDVI. Nesse sentido, com o artigo I objetivou-se delimitar zonas de manejo por meio de mapas de rendimento e NDVI oriundos de imagens de satélite em series históricas. Para isso, em uma área de 118 ha, selecionou-se três mapas de rendimento de diferentes culturas compreendidas entre os anos de 2010 a 2015 e para cada mapa de rendimento buscou-se selecionar as imagens satélite oriundas série Landsat que compreendessem uma data dentro do ciclo da cultura em questão a partir das quais procedeu-se o cálculo do NDVI e ainda com o intuito de verificar a estabilidade do NDVI gerado em diferentes ciclos de cultivo, foram selecionadas outras quatro imagens de satélites referentes a quatro cultivos, segundo o histórico de cultivo da área de estudo, compreendidos entre os anos de 2007 a 2013. Já no artigo II, o objetivo foi verificar a variabilidade causada pela cultura de cobertura de inverno na cultura de verão e se o índice de NDVI realizado “por terra” e com um RPAS é capaz de evidenciar essa variabilidade na cultura de verão. Em uma área 73,96 ha, aplicou-se uma malha amostral de 70,71 x 70,71 m (0,5 ha), onde realizou-se a amostragem de solo para a análise química e as avaliações de matéria seca e os nutrientes acumulados na cultura de cobertura inverno da aveia preta onde sobre esta, foi semeada no verão a cultura da soja, na qual nos estágios R5 e R5.5 foram realizadas avaliações com um sensor portátil “por terra” e com um RPAS para a obtenção do índice de NDVI e por final determinou-se o rendimento de grãos da soja, bem como, a população final de plantas. Com os resultados, constatou-se que O NDVI foi um bom parâmetro para delimitar duas zonas de manejo de alto e baixo potencial (artigo I) e que a matéria seca e os nutrientes acumulados na cultura de inverno interferem o rendimento da cultura de verão, sendo que o índice de NDVI realizado “por terra” ou com um RPAS foi eficaz em expressar essa variabilidade (artigo II).
9

Možnosti rozvoje a zajištění bezpečnosti dálkově řízených letadel (RPAS) v ČR / Development opportunities and ensure the safety of remote-controlled aircraft (RPAS) in Czech Republic

Habrnal, Lukáš January 2015 (has links)
Tato diplomová práce se zabývá možnostmi rozvoje a zajištěním bezpečnosti dálkově řízených letadel (RPAS) v ČR. Práce je rozdělena do 3 hlavních částí: legislativní, technické a bezpečnostní. V legislativní části najdeme současné a připravované předpisy pro RPAS. Technická část popisuje vývoj bezpilotního letectví až k dnešním civilním RPAS, které jsou popsány na příkladech používaných v ČR. V poslední části je věnován prostor oblastem, které, především z bezpečnostního hlediska, omezují rozvoj RPAS.
10

Aircraft Based GPS Augmentation Using an On-Board RADAR Altimeter for Precision Approach and Landing of Unmanned Aircraft Systems

Videmsek, Andrew R. 02 June 2020 (has links)
No description available.

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