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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
51

SAFE DESCENT : FACILITATING MOUNTAIN RESCUE WITH THE HELP OF DRONES

Fries, Alexander January 2022 (has links)
The goal of this project was to explore opportunities and develop a concept to improve the safety for mountain recreationists. Recreational outdoor activities have become increasingly popular in the past years. Engaging in those activities is associated with certain risks. The research phase included interviews with various stakeholders from mountain rescuers to mountain recreationists as well as field trips to mountain rescue stations. Existing research was analyzed. To acquire a better understanding of current and potential future preventive and reactive measures for emergencies, mountain rescue operations and dangers in mountains were explored. Interviews and continuous contact with professionals and my collaboration partner Flir throughout the whole project helped to form and validate various ideas and concepts. In emergency situations topographic circumstances, natural dangers and atmospheric conditions like cold, altitude and weather make mountain rescue time- and resource intensive. When air rescue resources are limited or the sight is too low due to unfavorable weather or night, the response time can dramatically increase up to several hours or overnight. This leaves the patient exposed to the hazardous mountain environment. Drones have the ability to bridge the gap between rescuers and patients to provide help at a much earlier stage of the rescue operation. They are already used on a small scale in mountain rescue and im- provements in technology and legislation are expected.The result of this project is a system to provide aid for people in emergency situations, even if air rescue is not available, to help them better prevail in the moun- tain conditions. It consists of a range of attachments that can be connected to various drone models. The different modules that can be attached allow forsearch for people in avalanches, search for missing people and delivery of emergency supplies to people in need of rescue. The delivery module has been de- veloped as a representative part of the system. It can be used to deliver supplies like shelter- and first aid equipment long before the professional arrive on site.
52

Design of an anechoic chamber for aeroacoustic testing and analysis of large UAS propellers

Vesa, Jonathan Hunter 25 November 2020 (has links)
This thesis details the design and construction of an anechoic chamber for acoustic testing and measurements of large UAS propellers. Three propellers are considered, as they are common propeller designs used for large UAS today. The knowledge and practices involved with acoustic testing and measurements in anechoic chambers, as well as the results of noise studies related to large UAS, are not widely available due in large part to the limited availability and use of large UAS in the public domain. Using established principles related to fundamental acoustic theory and propeller noise, the aeroacoustic noise from large UAS propellers was measured to study and evaluate the reduction in total aerodynamic noise. This data and research provides the ability to evaluate propeller noise in relation to the overall detectability of large unmanned aircraft systems.
53

Documentary Photography and the Edge of the Sword

Opal, Jack A. 16 June 2017 (has links)
No description available.
54

Evaluating the intention to use Industry 5.0 (I5.0) drones for cleaner production in sustainable food supply chains: an emerging economy context

Mahroof, Kamran, Omar, Amizan, Vann Yaroson, E., Quinn, G., Breen, L.,, Tenebe, S.A., Rana, Nripendra P., Sivarajah, Uthayasankar, Weerakkody, Vishanth J.P. 26 October 2023 (has links)
Yes / Purpose – The purpose of this study is to evaluate food supply chain stakeholders’ intention to use Industry 5.0 (I5.0) drones for cleaner production in food supply chains. Design/methodology/approach – We used a quantitative research design and collected data using an online survey administered to a sample of 264 food supply chain stakeholders in Nigeria. The partial least square structural equation model (PLS-SEM) was conducted to assess the research’s hypothesised relationships. Findings – We provide empirical evidence to support the contributions of I5.0 drones for cleaner production. Our findings showed that food supply chain stakeholders are more concerned with the use of I5.0 drones in specific operations such as reducing plant diseases which invariably enhances cleaner production. However, there is less inclination to drones adoption if the aim was pollution reduction, predicting seasonal output and addressing workers health and safety challenges. Our findings outline the need for awareness to promote the use of drones for addressing workers hazard challenges and knowledge transfer on the potentials of I5.0 in emerging economies. Originality – This is the first study to address I5.0 drones' adoption using a sustainability model. We contribute to existing literature by extending the sustainability model to identify the contributions of drones use in promoting cleaner production through addressing specific system operations. This study addresses the gap by augmenting a sustainability model, suggesting that technology adoption for sustainability is motivated by curbing challenges categorised as drivers and mediators.
55

Demonstrating an Equivalent Level of Safety for sUAS in Shielded Environments

Edmonds, Kendy Elizabeth 22 June 2021 (has links)
The current proposed unmanned aircraft system (UAS) detect and avoid standards require the same safety metrics, even when in close proximity to the ground or structures. This requirement has the potential to hinder low altitude small unmanned aircraft operations, such as local package delivery and utility inspection. One of the main safety metrics for UASs to adhere to is a ``well clear" volume that quantifies the vertical and horizontal separation UASs are required to maintain from manned aircraft. The current volume of 2000 feet horizontal and +/- 250 feet vertical does not provide credit for the safety benefit of being close to an obstacle where manned aircraft do not fly and could prove to be too restricting for low-level flight operations (i.e., under 400 feet above ground level). This thesis suggests using smaller safety metric volumes than the well clear volume to demonstrate that operations at lower altitudes can still be proven to be just as safe as if they were held to the larger well clear volume standard by using obstacle and terrain shielding. The research leverages simulation to analyze different safety metrics and provides an example use case in which the methodology of shielded operations is applied to demonstrate how this methodology can be applied for a safety case. / Master of Science / With the development of small unmanned aircraft system (sUAS) technologies have come many practical and regulatory challenges, especially in low altitude airspaces. At lower altitudes, manned aircraft are likely to be operating at lower velocities and restricting standards require UASs to maneuver against aircraft that may not present a significant risk of collision. The excessive avoidance maneuvering can cause the successful execution of even simple operations such as package delivery or survey operations to become difficult. The strict requirements have the potential to specifically inhibit sUAS beyond visual line-of-sight commercial operations, which are of great interest to the industry. This thesis describes a method for demonstrating an equivalent level of safety of small UAS operations when utilizing avoidance algorithms that leverage obstacle and terrain awareness. The purpose of this research is to demonstrate that by remaining close to obstacles, which pose a hazard to other aircraft, an unmanned aircraft can lower the risk of a mid-air collision and to demonstrate an equivalent level of safety for operations using a reduced safety metrics.
56

Multi-Sensor, Fused Airspace Monitoring Systems for Automated Collision Avoidance between UAS and Crewed Aircraft

Post, Alberto Martin 07 January 2022 (has links)
The autonomous operation of Uncrewed Aircraft Systems (UAS) beyond the pilot in command's visual line of sight is currently restricted due to a lack of cost-effective surveillance sensors robust enough to operate in low-level airspace. The current sensors available either have have high accuracy of locating targets but are too short of a range to be usable or have long ranges but have gaps in coverage due to varying terrain. Sensor fusion is one possible method of combining the strengths of different sensors to increase the overall airspace surveillance quality to allow for robust detect and avoid (DAA) capabilities; enabling beyond visual line of sight operations. This thesis explores some of the current techniques and challenges to use sensor fusion for collision avoidance between crewed aircraft and UAS. It demonstrates an example method of sensor fusion using data from two radars and an ADS-B receiver. In this thesis, a test bed for ground-based airspace monitoring surveillance is proposed for a low cost method of long-term sensor evaluation. Lastly, an potential method of a heterogeneous, score-based, sensor fusion is presented and simulated. / Master of Science / Long range operations of Uncrewed Aircraft Systems (UAS) are currently restricted due to a lack of cost-effective surveillance sensors that work well enough near the ground in the presence changing terrain. The current sensors available either have have high accuracy of locating targets but are too short of a range to be usable or have long ranges but have gaps in coverage due to varying terrain. Sensor fusion is a solution to this problem by combining the strengths of different sensors to allow for better collision avoidance capabilities; enabling these long range operations. This thesis explores some of the current techniques and challenges to use sensor fusion for collision avoidance between crewed aircraft and UAS. It demonstrates an example method of sensor fusion using data from two radars and an ADS-B receiver. In this thesis, a test bed for ground-based airspace monitoring surveillance is proposed for long-term sensor testing. Lastly, an potential method of a sensor fusion using different types of sensors is presented and simulated.
57

Asymmetric Strategies and Asymmetric Threats: A Structural-realist Critique of Drone Strikes in Pakistan, 2004-2014

Harris, Kathryn Elizabeth 28 January 2016 (has links)
As a component of the overall policy to defeat global terrorism and prevent attacks against the U.S., the Bush and Obama administrations have turned to unmanned aerial vehicles (UAVs), or drones. From 2004 to 2014, Pakistan has seen the largest volume of U.S. drone strikes targeting radical groups such as al Qaeda and the Taliban, a trend that is likely to continue for the foreseeable future. On the surface, using drones to eliminate terrorists while avoiding an official armed conflict aligns with the theory of neo- or structural realism developed by Kenneth Waltz. And yet although 9/11 served as the impetus for the U.S. to refocus attention on ameliorating the threat of terrorism and to initiate far-reaching measures to protect homeland security, there remains intense debate over whether or not the U.S. is actually more secure than it was prior to 9/11. While structural realism is still relevant to the current international system, the effects of drone strikes in Pakistan may set the U.S. on a path toward increasingly destabilizing situations that could lead to heightened insecurity and ultimately a change in power in the international system. The existing literature suggests that drone strikes in Pakistan are (1) leading to revenge-driven counter attacks, (2) intensifying radical anti-Americanism and creating more potential terrorists, (3) damaging the U.S. relationship with nuclear-armed Pakistan, (4) destabilizing the regions where drone attacks are launched, and (5) undermining American 'soft power.' The culmination of these five trends has the potential to disrupt the current balance of power in a way that is not in America's national interest. The unique security dilemma presented by the asymmetrical threat of terrorism and the asymmetrical response of drone strikes necessitates the continued evolution of neorealism as an IR theory. / Master of Arts
58

Architecture and Drones: Accomodating Unmanned Aerial Vehicles

Elmagri, Loay Hatem Rajab 11 February 2019 (has links)
Through out history, technological advancements have reshaped the built environment and its Architecture. The cities that we live in today were only made possible by the technologies of the first, second, and third industrial revolutions. Today, we are witnessing another technological revolution based on open source data and artificial intelligence. As there is an enormous amount of prosperous innovations that would directly impact Architecture design tools, building and finishing materials, and construction methods, there are also other innovations that would require spaces, buildings, and cities to be designed to accommodate them. Among the latter mentioned innovations is the Unmanned Aerial Vehicle (UAV), also know as drones. Like the automobile, drone technology will influence not only the way we live but also our design thinking and the components of our built environment. Along with drone's ability to fly, UAV's digital infrastructure is much more flexible and most importantly, invisible. Autonomous Drones' intelligent abilities allow them to provide a wide range of services in various fields such as; freight and delivery, transportation, infrastructure and buildings maintenance, survey, surveillance, policing, fire fighting, agriculture, and even construction, all of which will effectively reduce the amount of ground vehicle traffic, especially in populated cities. Today, as these possibilities are available and constantly under development, it is important for Architecture and Urban Design disciplines to address the challenge and provide comprehensive solutions to accommodate such a technology and allow its possibilities to prosper even further. The intent of this thesis is to study UAV technology and design a mix-use complex that embraces and accommodates UAV services such as; delivery, transport, freight, and maintenance. The complex hosts a residential tower, a vertical garden tower, ground level commercial spaces, and an underground drone hub. / Master of Architecture / Today, we are witnessing another technological revolution based on open source data and artificial intelligence. As there is an enormous amount of prosperous innovations that would directly impact architecture design tools, building and finishing materials, and construction methods, there are also other innovations that would require the built environment of our cities to be designed to accommodate them. Among the later mentioned innovations is the Unmanned Aerial Vehicle (UAV), also known as drones. Autonomous drones are flying robots with intelligent abilities which allow them to provide a wide range of services in various fields such as; freight and delivery, transportation, infrastructure and buildings maintenance, survey, surveillance, policing, fire fighting, agriculture, and even construction, all of which will are available today and constantly under development. Therefore, it is important for architecture and urban design disciplines to address the challenge and provide comprehensive solutions to accommodate such a technology and allow it to grow even further. The intent of this thesis is study drones and their future possibilities and to design a mixed-use complex that embraces and accommodates drone services such as; delivery, transport, freight, and maintenance. The complex hosts a residential tower, a vertical garden tower, ground level commercial spaces, and an underground drone hub.
59

Applications et services DTN pour flotte collaborative de drones

Laplace, Rémi 20 December 2012 (has links) (PDF)
Les travaux présentés dans cette thèse effectuée au LaBRI portent sur la mise en place d'une flotte de drones et le portage sur celle-ci d'applications collaboratives distribuées utilisant des communications asynchrones non sûres. Ces applications sont formalisées grâce au modèle de réétiquetage de graphes Asynchronous Dynamicity Aware Graph Relabeling System (ADAGRS) que nous proposons. Au delà des contributions théoriques, ces travaux ont débouché sur la mise en place du démonstrateur CARUS dans lequel cinq drones se partagent la surveillance d'une grille de 15 points d'incidents potentiels (au sol). Lorsqu'un drone détecte un incident, il s'en rapproche pour le traiter. Le reste de la flotte doit alors prendre en charge les points que ce drone ne traite plus.Les réorganisations nécessaires de la flotte se font en totale autonomie vis-à-vis du sol et sous hypothèse de perte éventuelle de drones et de messages.
60

Drones e drone art : poder militar, ética e resistência

Rodrigues, Anna Carolina Natale 06 May 2015 (has links)
Submitted by Nádia Paes (nadia66paes@gmail.com) on 2016-09-30T14:19:37Z No. of bitstreams: 1 DISS_2015_Anna Carolina Natale Rodrigues.pdf: 1941878 bytes, checksum: 83d67286141efc175526c206f4b5d8a9 (MD5) / Approved for entry into archive by Jordan (jordanbiblio@gmail.com) on 2016-09-30T16:16:19Z (GMT) No. of bitstreams: 1 DISS_2015_Anna Carolina Natale Rodrigues.pdf: 1941878 bytes, checksum: 83d67286141efc175526c206f4b5d8a9 (MD5) / Made available in DSpace on 2016-09-30T16:16:19Z (GMT). No. of bitstreams: 1 DISS_2015_Anna Carolina Natale Rodrigues.pdf: 1941878 bytes, checksum: 83d67286141efc175526c206f4b5d8a9 (MD5) Previous issue date: 2015-05-06 / CAPES / Aeronaves Remotamente Pilotadas, mais conhecidas como Drones nos textos da imprensa, são aeronaves que funcionam como dispositivos de vigilância e defesa, utilizados pelos Estados Unidos desde a Guerra do Vietnã. Por muito tempo esta tecnologia esteve nas mãos dos israelenses, mas, nos últimos anos, os Estados Unidos tornaram-se o maior produtor desse tipo de aeronave. A utilização desta tecnologia começou a se tornar conhecida no último governo Bush após os ataques de 11 de setembro com a chamada ‘Guerra ao Terror’. Mais recentemente, o governo Obama intensificou o seu uso, com o aumento de investimentos militares, fabricação e circulação desses dispositivos. Por mais que o uso civil desta tecnologia esteja aumentando, o foco da pesquisa ainda em andamento é a utilização dela no contexto militar, principalmente estadunidense. Há quase dois mil conflitos armados ao redor do mundo desde o novo milênio e o número cresce a cada dia. A violência legítima, a criminalidade e o terrorismo tornam-se indistinguíveis um do outro. Em decorrência disso, os termos de validação tendem a entrar em colapso. Os chamados drones podem ser operados a milhares de quilômetros de distância e costumam ser utilizados sem a autorização do espaço aéreo dos governos invadidos. Vive-se em um momento de conflitos difusos de pequenos inimigos em todo lugar e a utilização das Aeronaves Remotamente Pilotadas confirma a ideia da presença de um inimigo constante, e quando a guerra está na base da política, o inimigo tem a função constitutiva de legitimar a vigilância e os ataques. Se o inimigo não é mais concreto, compreensível e localizável sua aura é hostil, facilitando a legitimação daquilo que é na realidade insustentável. / Remotely Piloted Aircrafts also known through the press as Drones, are surveillance and defense devices used by The United States of America since the Vietnam war. For a long time, this technology was in the hands of the Israeli armed forces, but in the last few years, The United States became the largest producer of this aircraft. The use of Drones became known in the last Bush administration, after the attacks of September 11, with the so-called "War on Terror". Moreover, more recently in the Obama administration with the increasing manufacture of such devices. Even though the use of this technology among civilians are increasing, the focus of this ongoing research is its use in military context, mostly American. According to Hardt and Negri (2012), nowadays there are almost two thousand armed conflicts around the world since the new millennium. These numbers keep growing, therefore, the legitimate violence, crime and terrorism became indistinguishable from one another, the terms of validation tend to collapse. The remotely piloted aircrafts can be operated thousands of miles away and often without the airspace permission of the invaded governments. We are in a time of small and intern conflicts with small enemies everywhere. Moreover, using this aircraft confirms the idea of this constant enemy, and when war is at the base of politics, the enemy has the primary function to legitimate surveillance and attacks. If the enemy is no longer concrete, understandable and traceable, then its aura is hostile, facilitating the legitimacy of that is in reality unsustainable.

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