Download or read book Architecture de communication s curis e d une flotte de drones written by Jean-Aimé Maxa and published by . This book was released on 2017 with total page 229 pages. Available in PDF, EPUB and Kindle. Book excerpt: Grâce aux progrès de miniaturisation des systèmes embarqués, les mini-drones qu'on appelle en anglais Small Unmanned Aerial Vehicle (UAVs) sont apparus et permettent de réaliser des applications civiles à moindres coûts. Pour améliorer leurs performances sur des missions complexes (par exemple, pour contourner un obstacle), il est possible de déployer une flotte de drones coopératifs afin de partager les tâches entre les drones. Ce type d'opération exige un niveau élevé de coopération entre les drones et la station de contrôle. La communication entre les drones de la flotte est donc un enjeu important dans la réalisation des opérations d'une flotte de drones. Parmi les différentes architectures de communication qui existent, le réseau ad hoc s'avère être une solution efficace et prometteuse pour l'opération d'une flotte de drones. Un réseau ad hoc de drones ou UAV Ad hoc Network (UAANET) est un système autonome constitué d'une flotte de mini-drones et d'une ou plusieurs station(s) sol. Ce réseau peut être considéré comme une sous-catégorie d'un réseau ad hoc mobile (MANET) avec des caractéristiques spécifiques (vitesse importante des nœuds, modèle de mobilité spécifique, etc.) qui peuvent engendrer des baisses de performance du protocole de routage utilisé. Par ailleurs, la nature partagée du support de transmission et l'absence d'une infrastructure fixe pour vérifier l'authenticité des nœuds et des messages posent un problème de sécurité des communications. Compte tenu du caractère critique des données de charge utile échangées (en effet, un attaquant peut capturer un drone et l'utiliser à des fins malveillantes), il est important que les messages échangés soient authentifiés et qu'ils n'ont pas été modifiés ou retardés par un attaquant. L'authentification des messages est donc un des objectifs à atteindre pour garantir la sécurité du système Unmanned Aerial System (UAS) final. Diverses solutions de sécurité ont été conçues pour les réseaux sans fil, puis ont ensuite été adaptées aux réseaux MANET. Ces solutions peuvent s'étendre à des applications pour les réseaux UAANET, c'est pourquoi nous proposons dans cette thèse une architecture de communication fiable et sécurisée pour les flottes des drones. Dans ce travail, nous avons étudié en premier lieu l'application d'un réseau ad hoc mobile pour les flottes de drones. Nous examinons en particulier le comportement des protocoles de routage ad hoc existants dans un environnement UAANET. Ces solutions sont ainsi évaluées pour permettre d'identifier le protocole adéquat pour l'échange des données. Cela nous amène dans un deuxième temps, à proposer un protocole de routage intitulé Secure UAV Ad hoc routing Protocol (SUAP) qui garantit l'authentification des messages et détecte l'attaque wormhole. Cette attaque peut être définie comme un scénario dans lequel un attaquant enregistre les paquets en un point, et les rejoue à un autre point distant. L'attaque wormhole est particulièrement dangereuse lorsqu'un protocole de routage réactif (qui utilise le nombre de sauts comme métrique d'une route) est utilisé. Pour contrer cette attaque, le protocole SUAP permet d'une part d'assurer des services de livraison de donnés (une vidéo de télésurveillance) entre un drone distant et une station sol. D'autre part, le protocole SUAP possède également des partitions de sécurisation qui se basent sur une signature et une fonction de hachage pour assurer l'authentification et l'intégrité des messages. En ce qui concerne l'attaque wormhole, une technique qui consiste à corréler le nombre de sauts et la distance relative entre deux nœuds voisins est utilisée. Ce mécanisme permet de déduire la présence ou non d'un tunnel wormhole dans le réseau. En outre, cette architecture de communication est conçue avec une méthodologie de prototypage rapide avec l'utilisation d'une méthode orientée modèle pour tenir compte du besoin de validation du système UAS final.
Download or read book Conception et mise en oeuvre d une architecture de communication pour mini drones civils written by Ons Bouachir and published by . This book was released on 2014 with total page 170 pages. Available in PDF, EPUB and Kindle. Book excerpt: Le domaine des drones, engins volants sans pilotes, généralement appelé UAV pour Unmanned Aerial Vehicle, ont longtemps été un outil militaire. Ces dernières années, avec l'avènement de micro-drones, plus petits, légers et moins coûteux que leurs homologues à étendu l'utilisation des UAV au domaine civil. Afin d'améliorer les performances des drones sur de telles missions, des recherches sont menées afin de rendre les drones coopératifs. Une flotte de drones coopératifs sera alors capable de réaliser plus rapidement des missions plus complexes en partageant les différentes tâches entre les UAV. Ce genre d'opération nécessite un niveau élevé de coordination entre les drones rendu possible par un échange continu d'information entre eux et avec leur station de contrôle. Cet échange permet aux contrôleurs d'ajuster la mission selon les circonstances. La communication est donc vue comme un enjeu majeur dans l'évolution des opérations de ce genre de systèmes. Le réseau ad hoc est une solution prometteuse pour faire communiquer les drones entre eux et avec la station sol. Au cours d'une mission, une flotte de drones coopératifs, ayant chacun un rôle différent des autres, échange une variété de types de messages envoyés entre les UAV sur la liaison descendante (des drones vers la station sol) et sur la liaison montante. Ces messages ont des priorités et des besoins en termes de la qualité de service (QdS) qui diffèrent selon la tâche accordée à l'émetteur. Ces besoins peuvent varier selon le contenu du message et au cours du temps avec l'évolution et le changement de la tâche. Par la suite, la QdS doit être gérée par un module conscient de ces évolutions et capable de s'adapter à la variation des besoins et de fournir à chaque trafic sa demande durant toute l'opération. Cette thèse, financée par le projet européen D3CoS, propose un système nommé DAN " DCoS (Distributed Cooperative Systems) Ad hoc Network ", offrant des garanties en termes de différenciation de services selon une variété de critères choisis par les applications comme la tâche allouée à l'émetteur et le contenu du message. Ce système permet de proposer aux agents collaboratifs différents niveaux de QdS en fonction du type d'application utilisée qui peut être variable au cours du temps. Le système DAN devant être utilisé en environnement réel, il a été évalué à l'aide de deux moyens : la simulation et l'expérimentation réelle. Il a été implémenté sur Linux embarqué sur des cartes Raspberry Pi intégrées aux drones Paparazzi. Plusieurs tests ont été réalisés permettant de valider les résultats obtenus par simulations
Download or read book Guernsey Folk Lore written by Sir Edgar MacCulloch and published by . This book was released on 1903 with total page 624 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Dictionary of the French and English Languages written by Gabriel Surenne and published by . This book was released on 1856 with total page 580 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Aegeans in the Theban Tombs written by Shelley Wachsmann and published by Peeters Publishers. This book was released on 1987 with total page 246 pages. Available in PDF, EPUB and Kindle. Book excerpt: The wall paintings of several Theban tombs represent foreigners who present gifts that are sometimes typically Cretan or Aegean. Other foreigners, although labeled Princes of Keftiu (Crete), are represented as Asiatics. The aim of the present volume is to analyze these wall paintings in order to distinguish the Aegeans and their gifts. The author manages to establish their characteristics in nine Theban tombs, divides chronologically in two groups, and shows that the related figures reflect actual Aegeo-Egyptian relations in the time of the XVIIIth dynasty, down to c. 1470/1450 BC. This result is obtained by a careful comparison of represented gifts with undoubtedly Minoan objects and documents from the Aegean, especially Crete.
Download or read book MIT Lincoln Laboratory written by Eva C. Freeman and published by Lincoln Laboratory Massachusetts Institute of Technology. This book was released on 1995 with total page 320 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Dravidian Origins and the West written by Nicolas Lahovary and published by . This book was released on 1963 with total page 446 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Crossing Open Ground written by Barry Lopez and published by Vintage. This book was released on 1989-05-14 with total page 226 pages. Available in PDF, EPUB and Kindle. Book excerpt: In Crossing Open Ground, Barry Lopez weaves the same invigorating spell as in his National Book Award-winning classic Arctic Dreams. Here, he travels through the American Southwest and Alaska, discussing endangered wildlife and forgotten cultures. Through his crystalline vision, Lopez urges us toward a new attitude, a re-enchantment with the world that is vital to our sense of place, our well-being . . . our very survival.
Download or read book Share Attack written by Malcolm Stacey and published by Harriman House Limited. This book was released on 2015-08-03 with total page 145 pages. Available in PDF, EPUB and Kindle. Book excerpt: 80 must-read tips and techniques to get you started in trading Trading shares can make you rich - but it's not risk-free. You need years of experience to navigate the dangers and seize the best opportunities at the right time. Malcolm Stacey has done the hard work for you: he's learned how to be successful through years of his own experience and countless conversations with top traders. Now he's ready to share this knowledge and give you a head start. Probably Britain's best-known shares blogger, Malcolm has traded from his armchair for nearly 30 years. He's gone through it all, from frothy bull market bubbles to crunching crashes. As a BBC business reporter, he interviewed some of the most successful share traders in the world who revealed to him their top-secret strategies and tips. He's also spoken to countless business leaders to learn what makes a good company - the kind you want to be backing. In Share Attack, he distils all of this into 80 vital trading tips and techniques that you can put into practice right now. Filled with insight and experience, Share Attack is a trading book with teeth - a fascinating beginner's guide for those who want to start trading more actively. It's fast-moving and entertaining - and packed with years of techniques, tricks and red flags. You'll learn from Malcolm's early mistakes and benefit from his successes. Malcolm can't guarantee to make you rich by trading shares, but you can give yourself a much-needed edge by learning the top secrets of those who've done it all before. It's time for the Share Attack!
Download or read book Indigenous Men and Masculinities written by Robert Alexander Innes and published by Univ. of Manitoba Press. This book was released on 2015-11-06 with total page 408 pages. Available in PDF, EPUB and Kindle. Book excerpt: What do we know of masculinities in non-patriarchal societies? Indigenous peoples of the Americas and beyond come from traditions of gender equity, complementarity, and the sacred feminine, concepts that were unimaginable and shocking to Euro-western peoples at contact. "Indigenous Men and Masculinities", edited by Kim Anderson and Robert Alexander Innes, brings together prominent thinkers to explore the meaning of masculinities and being a man within such traditions, further examining the colonial disruption and imposition of patriarchy on Indigenous men. Building on Indigenous knowledge systems, Indigenous feminism, and queer theory, the sixteen essays by scholars and activists from Canada, the U.S., and New Zealand open pathways for the nascent field of Indigenous masculinities. The authors explore subjects of representation through art and literature, as well as Indigenous masculinities in sport, prisons, and gangs. "Indigenous Men and Masculinities" highlights voices of Indigenous male writers, traditional knowledge keepers, ex-gang members, war veterans, fathers, youth, two-spirited people, and Indigenous men working to end violence against women. It offers a refreshing vision toward equitable societies that celebrate healthy and diverse masculinities.
Download or read book Arctic Dreams written by Barry Lopez and published by Simon and Schuster. This book was released on 2024-07-23 with total page 300 pages. Available in PDF, EPUB and Kindle. Book excerpt: Winner of the National Book Award This bestselling, groundbreaking exploration of the Far North is a classic of natural history, anthropology, and travel writing. The Arctic is a perilous place. Only a few species of wild animals can survive its harsh climate. In this modern classic, Barry Lopez explores the many-faceted wonders of the Far North: its strangely stunted forests, its mesmerizing aurora borealis, its frozen seas. Musk oxen, polar bears, narwhal, and other exotic beasts of the region come alive through Lopez’s passionate and nuanced observations. And, as he examines the history and culture of its indigenous communities, along with parallel narratives of intrepid, often underprepared and subsequently doomed polar explorers, Lopez drives to the heart of why the austere and formidable Arctic is also a constant source of breathtaking beauty, mystery, and wonder. Written in prose as pure as the land it describes, Arctic Dreams is a timeless mediation on the ability of the landscape to shape our dreams and to haunt our imaginations.
Download or read book Autopsy in the 21st Century written by Jody E. Hooper and published by Springer. This book was released on 2018-11-08 with total page 202 pages. Available in PDF, EPUB and Kindle. Book excerpt: Autopsy as a field is enjoying an unexpected renaissance as new and improved uses are found for postmortem examination in quality improvement, education, and research. Increased interest in the autopsy is evident in the popular press as well as in national and international physician meetings.This text will provide an overview of topics the authors consider crucial to competent and effective autopsy practice in the 21st century. Each chapter will combine relevant theoretical background with current and practical experience-based guidance so that pathologists and clinicians can better utilize the autopsy to provide optimal value to families, patients, hospitals, and health systems. Distinguished contributors will provide a review of the rich history of autopsy practice, including assessments of how the past both informs autopsy practice and impedes its progress. The autopsy will be placed in the context of larger healthcare systems with chapters on the use of autopsy in quality improvement and evaluating the value of autopsy as a professional activity, as well as new technology that affects practice models. Better and more reproducible methods for reporting autopsy findings will be explored to exploit the full potential of autopsy data for cross-institutional research. Two chapters will also provide the first book-level review of the growing field of autopsies performed on an urgent basis to sample both diseased and normal control tissue for research. These “rapid research autopsies” are especially crucial to cancer research and the growth of personalized medicine, and the book will explain the science behind utilization of autopsy tissue and offer a full template for designing and delivering a successful rapid autopsy program. Additionally, pathologist and clinician contributors will highlight current recommendations for special techniques and ancillary testing in postmortem examinations to serve the needs of today’s patient populations. As resident education is re-examined by pathology and education authorities, new competency-based training models will almost certainly come to the fore. A chapter will examine approaches to the future training of medical students, residents, and fellows in an environment of changing autopsy exposure. A final chapter will summarize the vision for the autopsy as a clinical outcome measure, and valuable scientific resource. This book will be a new type of volume in the field of autopsy pathology. It differs from the presently available review references and atlases in that it provides guidance for readers to embrace transformations that are already taking place in the field. There currently is no resource that offers comprehensive guidance for modern autopsy practice and looks forward to what the field might become in the future.
Download or read book The Clay We Are Made Of written by Susan M. Hill and published by Univ. of Manitoba Press. This book was released on 2017-04-28 with total page 245 pages. Available in PDF, EPUB and Kindle. Book excerpt: If one seeks to understand Haudenosaunee (Six Nations) history, one must consider the history of Haudenosaunee land. For countless generations prior to European contact, land and territory informed Haudenosaunee thought and philosophy, and was a primary determinant of Haudenosaunee identity. In The Clay We Are Made Of, Susan M. Hill presents a revolutionary retelling of the history of the Grand River Haudenosaunee from their Creation Story through European contact to contemporary land claims negotiations. She incorporates Indigenous theory, fourth world post-colonialism, and Amerindian autohistory, along with Haudenosaunee languages, oral records, and wampum strings to provide the most comprehensive account of the Haudenosaunee’s relationship to their land. Hill outlines the basic principles and historical knowledge contained within four key epics passed down through Haudenosaunee cultural history. She highlights the political role of women in land negotiations and dispels their misrepresentation in the scholarly canon. She guides the reader through treaty relationships with Dutch, French, and British settler nations, including the Kaswentha/Two-Row Wampum (the precursor to all future Haudenosaunee-European treaties), the Covenant Chain, the Nanfan Treaty, and the Haldimand Proclamation, and concludes with a discussion of the current problematic relationships between the Grand River Haudenosaunee, the Crown, and the Canadian government.
Download or read book Cape Gelidonya a Bronze Age Shipwreck written by George Fletcher Bass and published by . This book was released on 1967 with total page 198 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Aspiration Biopsy for the Community Hospital written by David B. Kaminsky and published by . This book was released on 1981 with total page 253 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book A History of Seafaring Based on Underwater Archaeology written by George Fletcher Bass and published by . This book was released on 1972 with total page 320 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Nanoscale Thermodynamics written by Signe Kjelstrup and published by . This book was released on 2021 with total page 168 pages. Available in PDF, EPUB and Kindle. Book excerpt: This Special Issue concerns the development of a theory for energy conversion on the nanoscale, namely, nanothermodynamics. The theory has been applied to porous media, small surfaces, clusters or fluids under confinement. The number of unsolved issues in these contexts is numerous and the present efforts are only painting part of the broader picture. We attempt to answer the following: How far down in scale does the Gibbs equation apply? Which theory can replace it beyond the thermodynamic limit? It is well known that confinement changes the equation of state of a fluid, but how does confinement change the equilibrium conditions themselves? This Special Issue explores some of the roads that were opened up for us by Hill with the idea of nanothermodynamics. The experimental progress in nanotechnology is advancing rapidly. It is our ambition with this book to inspire an increased effort in the development of suitable theoretical tools and methods to help further progress in nanoscience. All ten contributions to this Special Issue can be seen as efforts to support, enhance and validate the theoretical foundation of Hill.
