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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.
41

Användning av drönarteknik vid överlåtelsebesiktning av hus

Hansson, Nicklas, Sjöberg, Maria January 2021 (has links)
Syftet med följande examensarbete har varit att undersöka vilken effekt implementering av drönare har vid överlåtelsebesiktningar, samt om detta är praktiskt genomförbart. Svårigheter med att besikta yttertak på grund av rådande arbetsmiljöregler samt den betydande fallrisken det medför ligger till grund för detta arbete. Arbetet har genomlyst rådande lagstiftning kring användandet av drönare som visar på att det är juridiskt genomförbart att använda denna metod. Studien har senare utförts genom aktionsforskning där en drönare har köpts in av företaget och utvärderats efter ett antal överlåtelsebesiktningar. I samband med flygningarna har ett antal frågor besvarats för att undersöka besiktningsteknikernas upplevelser av drönarflygningarnas nytta vid dessa besiktningar. Svaren har sedan sammanställts och i resultatdelen redovisas vilka effekter besiktningsteknikerna ansåg att drönare hade vid överlåtelsebesiktning.    Rapporten har visat att det finns flera fördelar med att använda drönarteknik i samband med överlåtelsebesiktning. Rekommendationen är därför att drönarteknik bör vara standard vid överlåtelsebesiktning. / This thesis aims to examine the effects of implementing drone techniques in support of transfer inspections, and also if this technique is feasible. Difficulties in conducting roof inspections due to current working environment regulations and the considerable risk of falling is the underlying reason of this thesis. Current legislation regarding drone usage has been reviewed, with the conclusion that this technique is legally applicable. The study has later on been conducted as actionresearch, where a drone has been purchased and evaluated after a number of transfer inspections has been performed. A number of questions have been answered during the flights in order to determine whether drone techniques have been of use for the inspection technicians. The answers have then been compiled in the results section, showing the technicians’ experienced effects of using drones in conjunction with transfer inspections. The report demonstrates several gains and advantages with drone techniques during inspections. Therefore, the recommendation is that drone techniques should be a standard when conducting transfer inspections. / <p>Betyg 2021-06-04</p>
42

Policy Innovation for an Uncertain Future: Regulating Drone Use in Southern California Cities

January 2019 (has links)
abstract: Over the past six years, the use of drones for recreational and commercial purposes has increased dramatically. There are currently over one million registered drones in the United States, and this number is expected to increase in the foreseeable future. For now, drones are a local phenomenon. The operational limitations prevent them from long range activity and federal policies prevent them from operating beyond the visual line of sight of the controller. The localized nature of drone operation makes them a particularly salient issue at the local regulatory level. At this level, cities must contend with the uncertainty of drone operation and a complex regulatory environment. Within a single metropolitan region, there are cities that may attempt to restrict the use of drones through various local ordinances while neighboring cities may have not even considered, let alone adopted, any type of regulation. The reasons behind these policy choices are not clear. In an effort to understand the factors involved in the decisions to adopt a local drone use policy, this dissertation leverages qualitative methods to analyze the policy process leading to local decisions. The study capitalizes on rich contextual data gathered from a variety of sources for select cities in Orange and Los Angeles Counties. Specifically, this study builds a conceptual framework from policy innovation literature and applies it in the form of content analysis. This initial effort is used to identify the catalysts for policy discussion and the specific innovation mechanisms that support or detract from the decision to adopt a local drone use ordinance. Then, qualitative comparative analysis is used to determine which configuration of factors, identified during the content analysis, contribute to the causal path of policy adoption. Among other things, the results highlight the role that uncertainty plays in the policy process. Cities that adopt a drone use ordinance have low levels of uncertainty, high numbers of registered drone users, and at least two neighboring cities that also have drone use policies. This dissertation makes a modest contribution to policy innovation research, highlights how a configurational analysis technique can be applied to policy adoption decisions, and contains several recommendations for regulating drone use at the local level. / Dissertation/Thesis / Doctoral Dissertation Public Administration and Policy 2019
43

Resource Allocation and Energy Management in Green Network Systems

Liu, Jiashang 29 September 2020 (has links)
No description available.
44

Information Visualization of Performance Indicators for Drones in Urban Areas : A Complementary Module for the Visual Research Tool UTM50

Kettisen, Anders January 2022 (has links)
Drones in low-altitude air space at a large scale is a new and ongoing field of research and there is a high possibility that we during the coming decades will see a rise in both commercial and state-driven drone activities in this space, especially in urban areas. This will require new ways in which to think and operate all air traffic management around the world. To support the research and realization of this, this master thesis will investigate a way to visualize performance indicators for drones that are related to key performance indicators used in air traffic today. This is done by researching commonly used performance metrics for air traffic and finding a suitable program that can visualize these in different graph types often used in information visualization, to build and evaluate an interactive dashboard that lets a user explore the performance data. The drone data used in this work is retrieved from a drone simulation program where delivery drones act between start, delivery and endpoints. / <p>Examensarbetet är utfört vid Institutionen för teknik och naturvetenskap (ITN) vid Tekniska fakulteten, Linköpings universitet</p>
45

Unmanned Aerial Vehicles for Geographic Data Capture: A Review / Obemannade Flygfarkoster för Insamling av Geografisk Data: En Översiktsstudie

Gustafsson, Hanna, Zuna, Lea January 2017 (has links)
In GIS-projects the data capture is one of the most time consuming processes. Both how to collect the data and the quality of the collected data is of high importance. Common methods for data capture are GPS, LiDAR, Total Station and Aerial Photogrammetry. Unmanned Aerial Vehicles, UAVs, have become more common in recent years and the number of applications continues to increase. As the technique develops there are more ways that UAV technique can be used for collection of geographic data. One of these techniques is the UAV photogrammetry that entails using an UAV equipped with a camera combined with photogrammetric software in order to create three dimensional models and orthophotos of the ground surface. This thesis contains a comparison between different geographic data capture methods such as terrestrial and aerial methods as well as UAV photogrammetry. The aim is to investigate how UAVs are used to collect geographic data today as well how the techniques involving UAVs can replace or be used as a complement to traditional methods. This study is based on a literature study and interviews. The literature study aims to give a deeper insight in where and how UAVs are used today for geographic data capturing with focus on three main areas: environmental monitoring, urban environment and infrastructure, and natural resources. Regarding the interviews companies and other participants using UAVs for geographic data collection in Sweden have been interviewed to get an accurate overview of the current status regarding the use of UAVs in Sweden. Advantages, disadvantages, limitations, economical aspects, accuracy and possible future use or development are considered as well as different areas of applications. The study is done in collaboration with the geographic IT company Digpro Solutions AB. The goal is to be able to present suggestions of how UAV data can be applied in Digpros applications. Information from the literature study and the interviews show that using a UAV makes it possible to cover a large range between terrestrial and aerial methods, and that it can replace or complement other methods for surveying and data collection. The use gives the possibility to get close to the object without being settle to the ground, as well as work environment profits since dangerous, difficult areas can be accessed from distance. The data can be collected faster, quicker, cheaper and more frequent. Time savings occurs in the measurement stage but compared to terrestrial methods more time is required for the post-processing of the data. The use in Sweden is limited due to difficulties linked to Swedish legislation regarding camera surveillance, as well as long waiting times for the permissions that is required to fly. However, a change in the camera surveillance law is expected which means that UAVs will be excluded from the law. That may result in great benefits for everyone within the industry as well as a continued development of the technique and the use of UAVs. / Inom GIS ar datainsamling en av de mest tidskrävande processerna. Både hur data samlas in samt kvaliteten ar av hög vikt. Några av de vanligaste metoderna för datainsamling idag är GPS, LiDAR, totalstation och fotogrammetri. Obemannade flygfarkoster, UAVs, har de senaste åren blivit allt vanligare och användningsområdena fortsätter att öka. I takt med att tekniken hela tiden utvecklas finns idag flertalet satt att med hjälp av UAVs samla in geografisk data. Med kamerautrustade obemannade flygfarkoster och fotogrammetriska programvaror ar det bland annat möjligt att skapa tredimensionella modeller samt ortofoton av markytan. Detta kandidatexamensarbete innehaller en jämförelse mellan terrestra- samt flygburna metoder för datainsamling och obemannade flygburna metoder. Syftet är att undersöka hur UAVs kan anvandas för att samla in geografisk data samt möjligheten att ersätta eller komplettera existerande metoder, samt att presentera en overgripande bild av UAVs anvandningsomåden. Denna studie bygger pa en litteraturstudie samt intervjuer. Litteraturstudien syftar till en djupare inblick i anvandningsområden för UAV tekniken med fokus på tre huvudområden: miljöövervakning, urbana miljöer och infrastruktur samt naturliga resurser. Under intervjuerna intervjuades företag och andra aktörer inom branschen med syftet att göra en nulägesanalys av hur UAVs används för insamling av geografisk data i Sverige. Det insamlade materialet analyserades med avseende pa användningsområden, för- och nackdelar, hinder, kostnader, noggrannhet samt möjlig framtida användning och utveckling av tekniken. Studien är gjord i samarbete med företaget Digpro Solutions AB som är verksamma inom geografisk IT. Målet är att efter studien kunna ge förslag på hur data insamlad med UAV kan appliceras på Digpros applikationer. Information fran intervjuerna och litteraturen har visat att UAV täcker ett stort spann mellan terrestra- och flygburna metoder, och att den kan ersätta eller utgöra ett komplement till många mät- och datainsamlingsmetoder. Användningen av UAVs innebär möjlighet till att samla in data på ett nära avstånd till objekt utan att vara bunden till marken. Den medför även arbetsmiljövinster då farliga, svårtillgängliga områden kan nås från avstånd. Data kan samlas in snabbare, enklare, billigare och mer frekvent. Tisdbesparingar sker i inmätningsskedet men jämfört med terrestra mätmetoder krävs dock mer tid för efterbearbetning av mätdatat. Användningen i Sverige begränsas av svårigheter kopplade till Svensk lagstiftning gällande kameraövervakning, samt långa väntetider på de tillstånd som kravs för att få flyga. Dock väntas en ändring i kameraövervakningslagen som innebär att drönare inte innefattas i lagen. Detta kan komma att medföra stora fördelar för samtliga inom branschen samt en fortsatt utveckling av tekniken samt användningen av UAVs.
46

Towards On-Device Detection of Sharks with Drones

Moore, Daniel 01 December 2020 (has links) (PDF)
Recent years have seen several projects across the globe using drones to detect sharks, including several high profile projects around alerting beach authorities to keep people safe. However, so far many of these attempts have used cloud-based machine learning solutions for the detection component, which complicates setup and limits their use geographically to areas with internet connection. An on-device (or on-controller) shark detector would offer greater freedom for researchers searching for and tracking sharks in the field, but such a detector would need to operate under reduced resource constraints. To this end we look at SSD MobileNet, a popular object detection architecture that targets edge devices by sacrificing some accuracy. We look at the results of SSD MobileNet in detecting sharks from a data set of aerial images created by a collaboration between Cal Poly and CSU Long Beach’s Shark Lab. We conclude that SSD MobileNet does suffer from some accuracy issues with smaller objects in particular, and we note the importance of customized anchor box configuration.
47

3D Path Planning for Radiation Scanning of Cargo Containers

Braun, Patrick Douglas 28 October 2022 (has links)
Every year, the ports of entry of the continental United States receive millions of containers from container ships for processing. These containers contain everything that the country imports, and sometimes regulated items can be hidden inside them in attempt to smuggle them illegally into the country. Some of these items may be radioactive material meant for criminal purposes and represent a threat to national security. The containers are currently being scanned for radioactivity as they leave the port, but before leaving the port, containers can sit inside the port for weeks. It can be beneficial to scan these containers before they are picked up to catch the illegal material sooner and reduce the risk of danger to those nearby. Uncrewed Aerial Systems can be useful for scanning container stacks in container fields since they can be attached with sensors and reach heights that are difficult for humans. They can also scan autonomously, requiring less over watch from people. This thesis attempts to solve the problem of autonomous search by using an initial 3D scan of the search area to input into a 3D path planning algorithm to generate a flight path that will sufficiently scan the search area while minimizing flight time. Coverage is a main area of concern, as well is computational complexity and time. In order to maintain security of the aircraft, the path must be generated on-board the aircraft, and as such use on-board, lightweight, computers. The approach taken in this thesis is by breaking the problem down into 2D layers, and then developing paths on each layer based on where the obstacles are. In order to maximize coverage, contours are generated around the obstacles. The vertices of the contours are then treated like points to visit in a Travelling Salesman Problem. To incentivize paths that run alongside the obstacles for better radiation detection, paths that do not run close to the obstacles are given a higher cost than those that do, resulting in a cost-minimizing path planning algorithm yielding paths that stay close to obstacles. The Travelling Salesman Problem algorithm then yields the most time effective path to cover the area while maintaining a distance healthy for radiation scanning from the obstacles. / Master of Science / Every year, the ports of entry of the continental United States receive millions of containers from container ships for processing. These containers contain everything that the country imports, and sometimes regulated items can be hidden inside them in attempt to smuggle them illegally into the country. Some of these items may be radioactive material meant for criminal purposes and represent a threat to national security. It can be beneficial to scan these containers before they are picked up to catch the illegal material sooner and reduce the risk of danger to those nearby. Uncrewed Aerial Systems can be useful for scanning container stacks in container fields since they can be attached with sensors and reach heights that are difficult for humans. They can also scan autonomously, requiring less over watch from people. This thesis attempts to solve the problem of autonomous search by using an initial 3D scan of the search area to input into a 3D path planning algorithm to sufficiently scan the search area while minimizing flight time.
48

Russian media reactions to Ukrainian drone strikes in 2022

Mellqvist, Carl January 2023 (has links)
On February 24, 2022, the Russian Federation launched a full-scale invasion of Ukraine, framed as a limited “special military operation”, rather than the largest invasion in Europe since World War II. Although Ukraine put up fierce resistance, the Kremlin doubled down on their “special military operation”, using the Russian information space to insulate their population from the realities of the catastrophic invasion. However, as the months passed, Ukrainian capabilities grew, and a new threat to the carefully cultivated image of the invasion as limited emerged: strikes on military bases on territory that had been held by Russia before February 24. This study looks at the Russian media space’s reaction to four drone attacks on Russian held territory through mainstream media. The study uses the method “Naming, Blaming, Claiming” with the aim of showing how Russian media identified the problem (naming), who was responsible (blaming), and what was done to mitigate the issue (claiming). It will be shown that the blame for these attacks shifted with time, from Ukraine to the West. Additionally, it provides insight into how the Russian information space, specifically news media, behaves during such events.
49

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.
50

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.

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