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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.
71

The good and the bad: UCAV counterinsurgency : how are the UCAV theories reflected in the counterinsurgency in Afghanistan and Pakistan?

Asplund Thidlund, Peter January 2016 (has links)
The modern battlefield is a changing environment where new ideas and technology are being tried and implemented. One such technology that has brought recent changes to the battlefield is the Unmanned Aerial Combat Vehicles (UCAV), commonly (and often incorrectly) referred to as “drones”. UCAV can be considered the new weapon of choice to deal with irregular opponents or terrorist organisations, such as those in Afghanistan and Pakistan. However, the use of UCAV is not without contradictory elements and leads to debate. It is within this debate that this study takes foothold. This study will be analysing the debate and issues surrounding this by evaluating four contrasting variables, measuring impact through different means and aiming to increase the understanding of UACV in the field. There are several crossovers in the analysis of all four variables citing the strengths and weaknesses of UCAV provisions in conflict. The analysis, however, conclude that a sole, holistic use of UCAV strikes would not resort in a termination of threats, such as the Taliban or Al-Qaida. This means that both the positive and the negative aspects of UCAV are seen in the conflict and do not contradict one another. Regretfully, this implicates that even if the Taliban and Al-Qaida becomes less effective due to the UCAV strikes, they will not perish.
72

Identification of Flying Drones in Mobile Networks using Machine Learning / Identifiering av flygande drönare i mobila nätverk med hjälp av maskininlärning

Alesand, Elias January 2019 (has links)
Drone usage is increasing, both in recreational use and in the industry. With it comes a number of problems to tackle. Primarily, there are certain areas in which flying drones pose a security threat, e.g., around airports or other no-fly zones. Other problems can appear when there are drones in mobile networks which can cause interference. Such interference comes from the fact that radio transmissions emitted from drones can travel more freely than those from regular UEs (User Equipment) on the ground since there are few obstructions in the air. Additionally, the data traffic sent from drones is often high volume in the form of video streams. The goal of this thesis is to identify so-called "rogue drones" connected to an LTE network. Rogue drones are flying drones that appear to be regular UEs in the network. Drone identification is a binary classification problem where UEs in a network are classified as either a drone or a regular UE and this thesis proposes machine learning methods that can be used to solve it. Classifications are based on radio measurements and statistics reported by UEs in the network. The data for the work in this thesis is gathered through simulations of a heterogenous LTE network in an urban scenario. The primary idea of this thesis is to use a type of cascading classifier, meaning that classifications are made in a series of stages with increasingly complex models where only a subset of examples are passed forward to subsequent stages. The motivation for such a structure is to minimize the computational requirements at the entity making the classifications while still being complex enough to achieve high accuracy. The models explored in this thesis are two-stage cascading classifiers using decision trees and ensemble learning techniques. It is found that close to 60% of the UEs in the dataset can be classified without errors in the first of the two stages. The rest is forwarded to a more complex model which requires more data from the UEs and can achieve up to 98% accuracy.
73

Modélisation, observation et commande d'un drone miniature à birotor coaxial / Modelling, Estimation and Control of a Coaxial Rotor UAV

Koehl, Arnaud 19 March 2012 (has links)
Les drones miniatures à voilures tournantes tendent aujourd'hui à devenir les nouveaux outils du fantassin, grâce à la polyvalence des missions auxquelles ils peuvent être employés. Leur principal atout concerne leur capacité à combiner le vol stationnaire et le vol de translation rapide, dans des environnements étroits et encombrés. Nous proposons ici l'étude d'un nouveau concept de drone atypique appelé GLMAV (Gun Launched Micro Air Vehicle), qui consiste à amener un véhicule hybride projectile/drone très rapidement sur un site d'intérêt éloigné, en utilisant l'énergie fournie par une arme portable. La première tâche concerne la modélisation aérodynamique du GLMAV. L'identification paramétrique du modèle aérodynamique est alors réalisée à partir de données expérimentales d'efforts, que nous pouvons a priori quantifier par un critère algébrique d'excitabilité persistante. Nous proposons ensuite des techniques de filtrage, afin d'estimer les paramètres anémométriques inconnus mais nécessaires pour connaître l'environnement aérodynamique dans lequel l'engin évolue. De plus, pour palier à la défaillance de capteurs embarqués et qui peuvent affecter l'information de vitesse linéaire après le tir, nous proposons un estimateur d'ordre réduit de la vitesse linéaire. Dans ces deux problèmes d'estimation, nous prouvons la stabilité des observateurs proposés. Enfin, nous proposons une structure de commande pour la stabilisation de l'engin en vol quasi-stationnaire à partir d'un modèle de synthèse linéaire. Les efficacités des méthodes proposées sont illustrées par des résultats de simulations numériques et des essais expérimentaux / The miniature rotary wing UAVs are now tending to become the new tools of the soldier, with the versatility of missions they can be used. Their main advantage concerns their ability to combine the hovering and translational fast flight in narrow and congested environments. We propose the study of a new and atypical UAV concept called GLMAV (Gun Launched Micro Air Vehicle), which must bring a hybrid projectile/UAV very quickly on a site of interest, using the energy delivered by a portable weapon. The first task concerns the modelling of the aerodynamic GLMAV model. The parametric identification of the aerodynamic model is then realized from experimental load data, that can be a priori quantified by a persistent-excitability-algebraic-criterion. We then propose two filtering techniques to estimate the unknown aerodynamic parameters but needful to determine the aerodynamic environment in which the vehicle operates. In addition, to compensate the failure of embedded sensors that can affect the linear speed information after the shooting, we propose a reduced-order estimator to conserve a good linear speed information. In both estimation problems we prove the stability of the proposed observers. Finally, we propose a control scheme for the stabilization of the aircraft in the quasistationary flight mode from a linearized GLMAV model. The efficiencies of the proposed methods are illustrated through numerical results and experimental tests
74

Security techniques for drones

Jongho Won (5930405) 10 June 2019 (has links)
<div>Unmanned Aerial Vehicles (UAVs), commonly known as drones, are aircrafts without a human pilot aboard. The flight of drones can be controlled with a remote control by an operator located at the ground station, or fully autonomously by onboard computers. Drones are mostly found in the military. However, over the recent years, they have attracted the interest of industry and civilian sectors. <br></div><div>With the recent advance of sensor and embedded device technologies, various sensors will be embedded in city infrastructure to monitor various city-related information. In this context, drones can be effectively utilized in many safety-critical applications for collecting data from sensors on the ground and transmitting configuration instructions or task requests to these sensors.</div><div> <br></div><div>However, drones, like many networked devices, are vulnerable to cyber and physical attacks.<br></div><div>Challenges for secure drone applications can be divided in four aspects: 1) securing communication between drones and sensors, 2) securing sensor localization when drones locate sensors, 3) providing secure drone platforms to protect sensitive data against physical capture attacks and detect modifications to drone software, and 4) protecting secret keys in drones under white-box attack environments.<br></div><div> <br></div><div>To address the first challenge, a suite of cryptographic protocols is proposed. The protocols are based on certificateless cryptography and support authenticated key agreement, non-repudiation and user revocation. To minimize the energy required by a drone, a dual channel strategy is introduced.<br></div><div>To address the second challenge, a drone positioning strategy and a technique that can filter out malicious location references are proposed.<br></div><div>The third challenge is addressed by a solution integrating techniques for software-based attestation and data encryption.<br></div><div>For attestation, free memory spaces are filled with pseudo-random numbers, which are also utilized to encrypt data collected by the drone like a stream cipher.<br></div>A dynamic white-box encryption scheme is proposed to address the fourth challenge. Short secret key are converted into large look-up tables and the tables are periodically shuffled by a shuffling mechanism which is secure against white-box attackers.
75

Employing concepts of the SDN paradigm to support last-mile military tactical edge networks / Empregando conceitos de redes definidas por software para apoio à redes táticas militares de última milha

Zacarias, Iulisloi January 2018 (has links)
Em um futuro próximo, “dispositivos inteligentes” serão massivamente empregados em campos de batalha. Essa já é uma realidade, porém, o número de dispositivos utilizados em campos de batalha tende a aumentar em ordens de magnitude. As redes de comunicação de dados serão essenciais para transmitir os dados que esses dispositivos coletam e transformá-los em informações valiosas utilizadas como suporte à atuação humana. O suporte à tomada de decisão, ou mesmo níveis de autonomia, permitindo que estes dispositivos coordenem outros dispositivos, exigem comunicação contínua. Desafios relacionados à comunicação surgirão devido à dinamicidade do ambiente. A configuração da rede deve refletir decisões superiores automaticamente. A grande escala das redes conectando os altos escalões, tropas, veículos e sensores, aliada à falta de padronização dos dispositivos, tornará a integração destes desafiadora. Em um ambiente tão heterogêneo, muitos protocolos e tecnologias coexistirão. As redes de campo de batalha são um elemento de suma importância nas operações militares modernas e conceito de guerra centrada em rede é uma tendência sem volta e influencia desde os altos escalões até o controle de tropas Embora estudos tenham sido realizados nessa área, a maioria deles aborda redes estratégicas de alto nível e portanto não levam em conta as “redes táticas de última milha” (TEN), que compreendem dispositivos de comunicação com recursos limitados, como sensores ou ainda pequenos veículos aéreos não tripulados. Em uma tentativa de preencher esta lacuna, esse trabalho propõe uma arquitetura que combina conceitos dos paradigmas de redes definidas por software (SDN) juntamente com redes tolerantes à atraso/disrupçoes (DTN), para aplicação em redes táticas de última milha. O uso de SDN em cenários com nodos móveis é avaliado considerando uma aplicação de vigilância que utiliza streaming de vídeo e medidas de Qualidade de Experiência (QoE) de usuário são coletadas. Com base nos resultados obtidos, uma aplicação em conjunto dos conceitos de SDN e DTN é proposta, além disso abordamos a escolha do nodo que atuará como controlador SDN na rede. Os experimentos foram executados utilizando um emulador de redes. Apesar de pesquisas adicionais serem necessárias – considerado requisitos de segurança, por exemplo – os resultados foram promissores e demonstram a aplicabilidade destes conceitos no cenários das TENs. / The future battlefield tends to be populated by a plethora of “intelligent things”. In some ways, this is already a reality, but in future battlefields, the number of deployed things should be orders of magnitude higher. Networked communication is essential to take real advantage of the deployed devices on the battlefield, and to transform the data collected by them into information valuable for the human warfighters. Support for human decision making and even a level of autonomy, allowing devices to coordinate and interact with each other to execute their activities in a collaborative way require continuous communication. Challenges regarding communication will arise from the high dynamics of the environment. The network adaption and management should occur autonomously, and it should reflect upper-level decisions. The large scale of the network connecting high-level echelons, troops on the field, and sensors of many types, beside the lack of communication standards turn the integration of the devices more challenging. In such a heterogeneous environment, many protocols and communication technologies coexist. This way, battlefield networks is an element of paramount importance in modern military operations Additionally, a change of paradigm regarding levels of autonomy and cooperation between humans and machines is in course and the concept of network-centric warfare is a no way back trend. Although new studies have been carried out in this area, most of these concern higher-level strategic networks, with abundant resources. Thus, these studies fail to take into account the “last-mile Tactical Edge Network (TEN) level,” which comprises resource constrained communication devices carried by troopers, sensor nodes deployed on the field or small unmanned aerial vehicles. In an attempt to fill this gap, this work proposes an architecture combining concepts from software-defined networking (SDN) paradigm and the delay-tolerant approach to support applications in the last-mile TEN. First, the use of SDN in dynamic scenarios regarding node positioning is evaluated through a surveillance application using video streaming and Quality of Experience (QoE) measures are captured on the video player. We also explore the election of nodes to act as SDN Controllers in the TEN environment. The experiments use emulator for SDN with support to wireless networks. Further investigation is required, for example, considering security requirements, however the results are promising and demonstrate the applicability of this architecture in the TEN network scenario.
76

La guerre par les drones : un système immunitaire ? : une étude du rapport entre corps, politique et nouvelles formes de conflit / Genealogy of disexposure : a philosophical approach on drone warfare

Portron, Margaux 30 March 2017 (has links)
Ce travail se fonde sur la littérature critique existante sur les drones militaires, des études de cas et le travail de Michel Foucault sur le biopouvoir pour mettre en évidence les ressorts du pouvoir immunitaire. Nous cherchons à définir la logique immunitaire et à montrer ses ramifications en utilisant une de ses incarnations : les avions sans pilote utilisés à des fins militaires pour la surveillance et le bombardement par les États-Unis notamment. Ce travail analyse principalement les relations de pouvoir auxquelles sont soumis les corps dans l’assemblage. Si les travaux actuels ont insisté sur la place du corps du pilote de drone, ou opérateur, dans l’assemblage disciplinaire, notre étude des corps au sol comme partie intégrante du dispositif homme-machine met en évidence une logique constitutive du nous et du eux. La souveraineté est en effet le mécanisme qui fonde un groupe sur le commun, en excluant les autres, et qui trace ses frontières sur le principe de préservation de ce groupe. Ces frontières peuvent être celles d’un État, du monde occidental, mais aussi de certains quartiers, dans les villes, plus rentables que d’autres. Ce souci de préservation d’une communauté va aller de pair avec le développement d’un racisme institutionnalisé servant à organiser les vies à protéger et celles qu’on peut abandonner et même, et c’est pour cela que le pouvoir immunitaire superpose biopouvoir et pouvoir souverain, à éliminer si l’on estime qu’elles posent une menace. / This work draws on the existing critical literature on drone warfare, case studies and Michel Foucault’s work on biopower to highlight how immunity unfolds. I seek to define immunity by using one of its embodiments: pilotless devices used in contemporary conflicts for surveillance and bombing, mostly by the United States. This work mainly analyses the power relations to which the bodies that form the drone assemblage are subjected. If current analyses have insisted on the position of the drone pilot, or drone operator, in the disciplinary assemblage, my focus on the bodies on the ground as an essential part of the man-machine apparatus shows a way of constituting us and them. Sovereignty is indeed the mechanism by which a group constitutes itself on what they have in common, excluding others, and which confuses its borders with the principle of preservation. These borders can be those of a State, of the western world, but also of some city neighbourhoods. This obsession with community preservation is going to develop in parallel with institutionalised racism, which serves to organise lives which must be protected and those which can be abandoned and even killed if considered a threat. This is why I argue that biopower and sovereign power overlap in immune power.
77

Dinâmica Reprodutiva e Influência das Áreas de Congregação de Zangões na Africanização de Apis mellifera (Apidae: Apini) no Brasil / Reproductive Dynamics and the Influence of Drone Congregation Areas of Apis mellifera on the Africanization Process in Brazil

Martínez Carantón, Omar Arvey 21 December 2006 (has links)
A introdução de 33 rainhas africanas (Apis mellifera scutellata) em 1956, com o objetivo de iniciar um programa de seleção e melhoramento genético no Brasil, e a posterior enxameação de algumas destas rainhas, deu inicio ao processo de Africanização, originando o poli-híbrido, denominado, Abelha africanizada. Este processo envolveu uma série de fatores biológicos e ambientais, cujas interações não são suficientemente claras. Os acasalamentos em abelhas melíferas ocorrem em sítios denominados como Áreas de Congregação de Zangões (ACZ), estes locais têm sido bem estudados em abelhas européias, porém, pouco pesquisados em abelhas africanizadas. Assim, é mister a necessidade de desenvolver novos estudos sobre o comportamento reprodutivo destas subespécies, que contribuíram para a rápida expansão das abelhas africanizadas nas Américas. Foram observados os comportamentos de vôos de 10 rainhas (Apis mellifera carnica e Apis mellifera africanizada) e de 126 e 146 zangões de cada raça, respectivamente. Observou-se 6 pontos, localizados no campus da USP de Ribeirão Preto, os quais poderiam ter uma maior concentração de zangões em vôo. Estes pontos foram analisados por meio de uma rainha fecundada presa a um balão preenchido com gás Helio e determinadas características ambientais. Todas as rainhas retornnaram ao núcleo com a marca de acasalamento e iniciaram o processo de postura. Os dados revelaram que não existem diferenças significativas (? = 0,05%) ao compararmos: A idade da rainha no seu primeiro vôo (T=123: P=0,185); a idade da rainha no vôo do acasalamento (t=1,721; P=0,104); o numero de vôos que cada rainha realizou (T=79,5; P=0,789); a duração do vôo de acasalamento (t=1,065; P=0,303); a temperatura no dia do vôo de acasalamento (t=0,263; P=0,796) e o horário do dia no qual ocorrem os vôos de acasalamento (t = 0,0; P=1,0). A atividade de vôo dos zangões carnicos nunca precedeu o horário as 14:15 e 14:30h para zangões carnicos e africanizados, respectivamente, confirmando que não existem diferenças significativas no período do dia em que estes realizam seus vôos (t = -3,11E-015; P = 1,000). Dos 6 pontos observados, somente um ponto não atraiu zangões à isca. Não foram encontrados diferenças significativas entre as diferentes ACZ (P = 0,109). Ao analisar a velocidade do vento (m/s), a analise de variância encontrou diferenças significativas entre as diferentes ACZ (P=<0,001), porém não influenciando a presença de zangões na isca. Dados coletados neste experimento revelaram que os zangões freqüentam estas áreas durante condições de vento superiores a 4 m/s, e em algumas ocasiões com ventos de 8.1 m/s. Também foi observado que os zangões realizam seus vôos de acasalamento em dias nublados e com pouca luminosidade. Não existiu uma preferência, pelos zangões, por determinadas ACZ, constatando-se que o ambiente oferece muitos espaços abertos típicos de ACZ, garantindo e facilitando o acasalamento destas abelhas. / The introduction of 33 African queens ( Apis mellifera scutellata ) in 1956 , aiming to start a program of selection and breeding in Brazil , and later some of these swarming queens , began the process of Africanization , yielding poly - hybrid called , \" Africanized Bee \" . This process involved a number of biological and environmental factors whose interactions are unclear. Mating in honeybees occur at sites referred to as Areas of Congregation Hornets ( ACZ ) , these sites have been well studied in European bees , but little researched in Africanized bees . Thus , it is essential the need to develop new studies on the reproductive behavior of these subspecies, which contributed to the rapid expansion of Africanized bees in the Americas . Behaviors Flight 10 queens ( Apis mellifera and Apis mellifera Africanized carnica ) and 126 and 146 Hornets each race respectively were observed . There was 6 points , located in the USP , Ribeirão Preto , which could have a higher concentration of drones in flight campus . These points were analyzed by means of a fertilized queen attached to a balloon filled with helium and certain environmental characteristics. All queens retornnaram the core branded mating and begun the process of laying. The data revealed no significant differences when comparing : The age of the queen on her first flight (T = 123 : P = 0.185 ) ( = 0.05 % ? ) ; the age of the queen in flight mating ( t = 1.721 , P = 0.104 ) ; the number of flights that each queen performed (T = 79.5 , P = 0.789 ) ; the flight duration of mating ( t = 1.065 , P = 0.303 ) ; the temperature on the mating flight ( t = 0.263 , P = 0.796 ) and time of day in which mating flights occur ( t = 0.0, P = 1.0 ) . Flight activity of CARNICOS Hornets never preceded the hours 14:15 and 14:30 for CARNICOS and Africanized drones, respectively , confirming that there are no significant differences in time of day in which they perform their flights ( t = -3.11 and -015 , P = 1.000) . 6 of the observed points , only one point not attracted to the bait Hornets . No significant differences were found between the different ACZ (P = 0.109 ) . By analyzing the wind speed ( m / s ) , analysis of variance found significant differences between the different ACZ ( P = < 0.001), but not influencing the presence of drones at the bait . Data collected in this experiment revealed that the Hornets frequent these areas during windy conditions exceeding 4 m / s , and on some occasions with winds of 8.1 m / s . It was also observed that the Hornets perform their mating flights on cloudy days and low light . There was a preference by the Hornets , by certain ACZ , noting that if the environment offers many open spaces typical of ACZ , ensuring and facilitating mating these bees.
78

The Unmanned Aerial Systems (UASs) Industry and the Business Impacts of the Evolution of the Federal Regulatory Environment

Spencer, Darren W. 12 November 2018 (has links)
Despite the explosion of popularity of UASs, and the recognition that such systems must find a way to safely operate alongside manned aviation, a literature review by this author as well as interviews with three commercial aerial photography companies in Tampa Bay, Florida, indicate that regulatory restrictions are still the greatest obstacle to law abiding commercial UAS operators. It can take six to eight months with a backlog of 12,000 waiver applications to get either a Part 333 or Part 107 exemption, which grants FAA permission for a commercial operator to fly a UAS inside controlled airspace (Gardner, 2018). A manned pilot can file a flight plan and hover a helicopter over the same area in just a few hours. The purpose of this research was to determine what industry experts perceive the future of UAS regulations hold, and how the industry will be impacted in both the short term of 5 years and less, and long-term of 5 years or more. UAS industry expert interviews were conducted in the “reflection of the meaning”, semi-structured style, with each interviewee given the latitude to discuss topics as they came to mind. A preset approved bank of questions helped to guide the interview, but in many cases as experts in the field, the interviewees naturally discussed the topics covered in the preset questions and the interview adapted to avoid unnecessary repetition. One interview was conducted in-person, but the rest were via phone calls due to geographical separation.
79

Exploring the Role of Building Modeling and Drones in Construction.

Efosa, Alohan January 2019 (has links)
No description available.
80

MNT à très haute résolution spatiale pour la représentation 3D de ravines d'érosion en montagne

Jacome Pereira, Andrés 17 December 2009 (has links) (PDF)
Le suivi et la compréhension de la dynamique spatio-temporelle de l'érosion par ravinement en zones de Badlands ont besoin de méthodes de caractérisation détaillée, rapide et facilement reproductibles de ces phénomènes et de leurs manifestations sur le terrain. Nous avons testé deux approches d'observation spatiales afin de répondre à ces besoins : une approche aérienne (stéréophotogrammétrie d'images drone), et une approche terrestre (LiDAR terrestre). Pour l'approche aérienne, une combinaison adéquate de la préparation de terrain, la compensation des erreurs systématiques issues de l'acquisition d'images et la stratégie de corrélation d'image, nous a permis d'obtenir une précision, un détail et une cohérence hydrographique des MNT drone à la limite de la donnée (résolution d'image originale au sol autour de 3 cm). Par rapport à l'approche terrestre, l'analyse du bruit de la mesure LiDAR sur tôles avec des formes géométriques connues nous montre une dispersion autour de 1 cm pour une distance de mesure de 30 m. L'application d'une moyenne simple à un pas régulier d'un centimètre permet de réduire le bruit et aussi de récréer les formes de plus de 3 cm. Le rapport " avantages-contraintes " entre ces deux approches nous montre que l'approche aérienne produit des MNT avec une étendue et une continuité importante, tandis que l'approche terrestre produit des MNT plus précis et détaillé. Les résultats révèlent l'énorme potentiel du vecteur drone pour le développement des MNT peu coûteux. D'autre part, le LiDAR terrestre se révèle comme un système de lever de terrain permettant une rapidité et une répétitivité de mesure, ainsi qu'un niveau de détail intéressant.

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