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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.
301

Effects of Movement on Biometric Facial Recognition in Body-Worn Cameras

Julia Bryan (8788169) 01 May 2020 (has links)
<p>This study examined how three different manipulations of a single policing stance affected the quality scores and matching performance in a biometric facial recognition system; it was conducted in three phases. In the first phase, the researcher collected qualitative survey data from active, sworn law enforcement officers in 15 states. In the second phase, the researcher collected quantitative data using a single facial recognition subject and a static body-worn camera mounted to an adjustable tripod. In the third phase, the researcher collected quantitative data from body-worn camera-equipped law enforcement officers who filmed a stationary target as they executed a series of specified movements from the interview stance. The second phase tested two different body-worn cameras: one that is popular among law enforcement agencies in the United States, the Axon Body 2; and one that is inexpensive and available to the general public via a popular internet commerce website. The third phase tested only the Axon Body 2. Results of the study showed that matching results are poor in a biometric system where the test body-worn camera was the sensor, with error rates as high as 100% when the body-worn camera wearer was in motion. The general conclusion of this study is that a body-worn camera is not a suitable sensor for a biometric facial recognition system at this time, though advances in camera technology and biometric systems may close the gap in the future. </p>
302

Nätverksbaserade övervakningskameror i hemmet : Hur påverkar kamerorna den upplevda integriteten? / Network-based surveillance cameras in homes : How is the perceived integrity affected by the cameras?

Lundmark, Hedda January 2020 (has links)
Det har kommit att bli allt vanligare att installera nätverksbaserade övervakningskameror i hemmet som en säkerhetsåtgärd. Tidigare studier som undersöker nätverksbaserade övervakningskameror visar att dessa kameror utgör en möjlig säkerhetsrisk för de boende då det teoretiskt sätt är möjligt för personer som har kunskaper i att bryta sig in i datorsystem att spionera på de boende i hemmet genom övervakningskamerorna. Detta arbete har syftat till att undersöka om människor uppfattar den nätverksbaserade övervakningskameran, vars avsedda verkan är att övervaka hemmet och skydda det mot inbrott, som en säkerhetsrisk för intrång i deras integritet. Genom kvalitativa intervjuer undersöktes användares upplevelse av nätverksbaserade övervakningskameror i hemmet. Studien omfattade sex deltagare vilka rekryterades genom ett kriteriebaserat snöbollsurval. Genom en kvalitativ innehållsanalys kom studien fram till ett resultat som visar på samband i hur dessa övervakningskameror påverkar deltagarnas upplevda integritet i hemmet. Till exempel visade resultatet att deltagarna initialt kände sig iakttagna av dessa kameror. Dessa samband kan ligga till grund för fortsatt forskning kring hur nätverksbaserade övervakningskameror kan utvecklas för att förbättra användarupplevelsen av dem. / It has become increasingly common to install network-based surveillance cameras in homes as a security measure. Previous studies examining network-based surveillance cameras shows that these cameras pose a possible security risk to users as it is theoretically possible for people who have the knowledge to break into computer systems to spy on the residents of a home through the surveillance cameras. This study aimed to investigate whether users perceive the network-based surveillance camera, whose purpose is to monitor the home and protect it from intruders, as a security risk of intrusion into their privacy. Through qualitative interviews the users experience of network-based surveillance cameras in home has been examined. The study included six participants who were recruited though a criterion-based snowball selection. Through a qualitative content analysis, the study resulted in correlations between the participants experience of the network-based surveillance cameras and their impact on the participants perceived integrity. For example, the result showed that the participants initially felt observed by these cameras. The findings can be basis for further research on how network-based surveillance cameras can evolve to improve the user experience.
303

La nueva corriente cinematográfica que propone Emmanuel Lubezki en sus películas de la última década / The new cinematographic current that Emmanuel Lubezki proposes in his films

Sosa Suarez, Ruben Enrique 04 May 2020 (has links)
En este estudio se examinan los recursos de la cinematografía de Emmanuel Lubezki en relación a las nuevas corrientes que se han generado debido al tratamiento que este le ha dado a sus películas de la última década, por medio de la investigación de papers anteriores que tratan el tema del cine de Lubezki y porque lo hace reconocido y único en su estilo, también, la visualización de variedad de entrevistas en las que Lubezki explica el sentido que el toma y lo que aprendió durante su crecimiento como cineasta en el cine de actual. La información recogida nos muestra los aspectos básicos en los que se fija un cinematógrafo, como la iluminación, la composición, las cámaras, objetivos, etc. Se realiza un estudio de todos estos elementos basados en el respectivo uso que hacia Lubezki de estos como estrategia para reconocer el estilo del cineasta. / This study examines the resources of Emmanuel Lubezki's cinematography in relation to the new currents that have been generated due to the treatment that he has given to his films of the last decade, through the investigation of previous papers that deal with the Lubezki's film theme and because it makes him recognized and unique in his style, also, the visualization of a variety of interviews in which Lubezki explains the meaning he takes and what he learned during his growth as a filmmaker in current cinema. The information collected shows us the basic aspects in which a cinematograph is fixed, such as lighting, composition, cameras, lenses, etc. A study is made of all these elements based on Lubezki's respective use of these as a strategy to recognize the filmmaker's style. / Trabajo de investigación
304

Polisiära och lagstiftande åtgärder i syfte att öka gångtrafikanters trafiksäkerhet : En översiktsstudie / Police and legislative measures with the aim of increasing road safety for pedestrians : A scoping review

larsson, dennis January 2023 (has links)
Background: The whole of society is facing major challenges regarding the ongoing climate change and the possibility of creating sustainable development. This also largely applies to today's trafficsystem, which needs to change to more sustainable trffic system. Increased active travel is a nescessery for reaching the set goals that exist when it comes to sustainable travel. Increased active travel will lead to more unprotected road users in the trafficsystem, one group of unprotected road users are pedestrians. An increased number of pedestrians in the trafficsystem requires additional efforts to ensure traffic safety for that group. Method: An scoping review is carried out in which police and legislative measures aimed at increasing road safety for pedestrians are evaluated. The purpose of the study is to gain knowledge about what measures the current research proposes to increase traffic safety and to come up with proposals for additional areas where more research is needed. The study builds on two previous literature studies that superficially touched on the subject. Seven scientific articles are taken from these literature studies, a further 13 scientific articles are selected after a literature search. A total of 20 scientific articles that meet the inclusion criteria are included and analyzed. In order to assess whether Swedish authorities implement effective police and legislative measures with the aim of increasing traffic safety for pedestrians, a comparison is made between the measures proposed by the research and the measures that two Swedish authorities, the Swedish Transport Agency and the Swedish Police Agency, present in their documents Aktionsplan för säker vägtrafik 2022–2025 - 250 åtgärder som 33 myndigheter och aktörer avser att vidta för ökad trafiksäkerhet samt Polismyndighetens strategi inom trafiksäkerhetsarbetet. Results: The study shows that targeted police measures aimed at fining individuals who break traffic rules in a certain place during a certain time have a positive effect on pedestrian traffic safety. The focus should be on increasing rule compliance and reducing the number of speed limit violations by motorists, as well as encouraging pedestrians not to walk against red lights. The legislative measures that the scoping review shows have the best effect are lowering the speed limit and car-free zones on stretches of road where many pedestrians are moving. Conclusions: The conclusions that thos scoping review draws are that further research is required in the connection between reduced average speed and the number of traffic accidents which leads to personal injuries to pedestrians, as well as the part of police and legislative measures in different action programs that include several different measures that are implemented together. The police authority is working towards a reduced average speed of motorists through targeted police measures, which is in line with the measures proposed by the existing research in the area. However, there is nothing in the document about targeted police measures against pedestrians in order to increase rule compliance by that group, which is something that the Police Authority is recommended to develop. In the Swedish Transport Agency's action plan for the years 2022-2025, no measures are mentioned to increase pedestrian traffic safety linked to traffic accidents. Only measures to reduce the number of fall injuries are presented. The Swedish Transport Agency is therefore recommended to further develop its action plan and also have it include legislative measures such as reduced speed limits or car-free zones on road sections where many pedestrians move.
305

Feasibility of Event-Based Sensors to Detect and Track Unresolved, Fast-Moving, and Short-Lived Objects

Tinch, Jonathan Luc 13 July 2022 (has links)
No description available.
306

Automation and Autonomy : Developing and Evaluating Open Learning Material on IR Cameras in Automation Applications / Automation och Autonomi

Ahlberg, Victor, Frid, Julia January 2019 (has links)
This master thesis project was based on the development and evaluation of an open learning material in thermal imaging for automation applications. The outsourcer – FLIR Systems – wanted a three-day course covering all necessary topics for infrared cameras in automation applications. These topics include thermography, optics, detectors, networks, protocols, and more. The open learning material was designed to function as a three-day, self-paced, distance course, and it was based on theories of andragogy, self-directed learning and transformative learning. The master thesis process was essentially divided into two phases: the development phase and the evaluation phase. The method for the development phase was based on a literature study. The literature on creating open learning material included ways of compensating for the lack of social interaction in distance courses, such as a friendly, warm narrator using the pronoun “I”, encouraging phrases, and self-assessment questions (SAQs). An SAQ is a framing of question intended to guide the learner towards self-assessment of his or her learning and knowledge. The vital part of the SAQ is the response, where not only the correct answer is given, but feedback on the wrong choices too. The development of the open learning material was an iterative process where discussion with supervisors at FLIR Systems and KTH Royal Institute of Technology led to improvements of the material. The evaluation phase consisted of two tests with test subjects. The first test was conducted by sending a sample unit of the material to test subjects around the world along with a questionnaire. The main objective was to test the tone and style of the material. There were variations in the result, but the majority found the material friendly and readable. The second test was an in-house test with three participants. Three sample units of the material was used, and the main objective was to test the usability of the material and the test subjects’ perceived learning process. The usability of the material varied with the three test subjects and depended on their technological prerequisites and reading comprehension in English. All test subjects responded positively to their perceived learning outcome. The following conclusions were drawn: the open learning material has the potential to promote autonomous and self-directed learners and can be used as a basis for further development – such as web-based courses and teacher-led classes. The open learning material as a whole and the results and analysis from the tests are included as appendices. / Detta examensarbete baserades på utveckling och utvärdering av ett öppet läromedel i termografi för automationstillämpningar. Uppdragsgivaren – FLIR Systems – hade uttryckt ett behov av en tredagarskurs som täckte alla nödvändiga ämnen för infraröda kameror för automationstillämpningar. Dessa ämnen var bland annat termografi, optik, detektorer, nätverk, protokoll med flera. Det öppna läromedlet var designat för att fungera som en tredagars distanskurs och det var baserat på teorier om andragogik, självstyrt lärande och transformativt lärande. Examensarbetets process bestod i huvudsak av två faser: utvecklingsfasen och utvärderingsfasen. Metoden för utvecklingsfasen baserades på en litteraturstudie. Litteraturen i skapande av öppet läromedel inkluderade tillvägagångssätt för att kompensera för bristen av social interaktion i distanskurser, så som en vänlig och varm berättarröst som använder pronomenet ”jag”, uppmuntrande fraser och självbedömningsfrågor (SAQ, Self-Assessment Question). En självbedömningsfråga är en frågeställning menad att leda den lärande mot självbedömning av hens lärande och kunskap. Den viktiga delen av självbedömningsfrågan är responsen, där inte bara det rätta svaret är givet, utan också feedback på de felaktiga svaren. Utvecklingen av det öppna läromedlet var en iterativ process där diskussion med handledare på FLIR Systems och Kungliga Tekniska högskolan ledde till förbättringar i materialet. Utvärderingsfasen bestod av två test med försökspersoner. Det första testet utfördes genom att skicka en provenhet av materialet till försökspersoner över hela världen tillsammans med en enkät. Huvudsyftet med testet var att testa tonen och stilen på materialet. Resultatet var varierande, men majoriteten av testpersonerna fann materialet vänskapligt och läsligt. Det andra testet var ett internt test med tre deltagare. Tre provenheter från materialet användes och huvudsyftet var att testa användbarheten av materialet och försökspersonernas upplevda läroprocess. Användbarheten av materialet varierade hos de tre försökspersonerna och berodde på deras tekniska förutsättningar och läsförståelse i engelska. Alla försökspersoner gav positiv respons om deras upplevda läranderesultat. Följande slutsatser drogs: det öppna läromedlet har potential att främja autonomt och självstyrt lärande, samt kan användas som en bas för fortsatt utveckling så som webbaserade kurser och lärarledda kurser. Det öppna läromedlet i sin helhet och resultat och analys av testen är inkluderade som bilagor.
307

Interactions spatiales et temporelles entre les chiens libres et les carnivores sauvages à proximité des villages nordiques du Nunavik dans un contexte de transmission d’une maladie zoonotique : la rage

Frenette, Marie-Christine 04 1900 (has links)
Dans l'Arctique, le risque de transmission de maladies zoonotiques comme la rage est encore une préoccupation pour la santé publique, avec plusieurs cas rapportés chaque année chez différentes espèces animales. L’interface entre la faune sauvage, les animaux domestiques et les humains pour la transmission de maladies sera en augmentation en raison des pressions grandissantes du développement anthropique et du réchauffement climatique. Les interactions directes entre les chiens domestiques des villages nordiques et les renards sauvages, les principales sources d’exposition à la rage, sont des évènements critiques pour l’exposition des humains au virus, mais très peu d’études se sont attardées à ce sujet. Les objectifs de ce projet sont 1- de décrire et de quantifier l’activité spatiale et temporelle des renards et des chiens libres et d’identifier les facteurs anthropiques et environnementaux qui influencent leur présence à proximité et dans les villages nordiques, 2- de quantifier les contacts directs et le potentiel d’interactions entre les renards et les chiens libres afin de mieux identifier les périodes et les zones avec un risque de transmission de la rage, 3- de comparer et discuter des résultats de l’activité des renards et des chiens libres et leur potentiel d’interactions entre les deux villages nordiques à l’étude et 4- d’identifier des méthodes de gestion pour diminuer les opportunités d’interactions entre les renards et les chiens libres. Afin de détecter la présence des deux carnivores, un réseau de caméras automatiques a été installé sur une grille spatiale autour et à l’intérieur de deux villages typiques du Nord, Kuujjuaq (près de la limite des arbres) et Inukjuak (à > 100 km de la limite des arbres). Pour chaque station caméra, différents facteurs anthropiques et environnementaux ont été évalués (distance au dépotoir, distance à l’aéroport, densité d’habitations, densité de chiens de traîneau, distance aux rues, distance à l’eau, indice de végétation). Les contacts directs et les indices d’interaction ont été calculés pour évaluer le potentiel d’interactions entre les renards et les chiens libres. Les opportunités d’interactions entre les renards et les chiens sont plus élevées à l’aube et au crépuscule pendant les mois d'octobre et de novembre en périphérie des deux villages, particulièrement près des chiens de traîneau et légèrement près du dépotoir municipal (KU) et de l’aéroport (IN). Les renards roux et les renards arctiques ont été observés à proximité et dans les deux villages, mais les renards roux sont plus souvent observés à Kuujjuaq (87% des observations) qu’à Inukjuak (renards arctiques : 74% des observations), ce qui reflète également des particularités biotiques et abiotiques uniques à chaque village. Les résultats suggèrent que les opportunités d’interactions entre les renards et les chiens représentent un risque d’exposition à la rage pour les chiens et les humains, et possiblement pour d’autres pathogènes nordiques transmissibles entre les chiens et la faune. Cependant, les évènements de contacts directs interspécifiques renard-chien sont rares et les opportunités d’interactions sont concentrées dans le temps et dans des zones restreintes, ce qui peut aider à cibler des mesures préventives visant à limiter les évènements de transmission. Cette étude fournit la première documentation sur l'activité des renards et leurs interactions avec les chiens libres dans les villages de l'Arctique. L’application d’une approche « Une seule Santé » devrait être utilisée pour prévenir ou diminuer le risque de transmission de la rage entre les renards et les chiens. / In the Arctic, the risk of transmission of zoonotic diseases like rabies is still a public health concern, with several cases reported each year in different animal species. The interface between wildlife, domestic animals and humans for disease transmission will be increasing due to pressures from anthropogenic development and global warming. Direct interactions between domestic dogs in northern communities and wild foxes, the main source of rabies exposure, are critical of human exposure to the virus, but very few studies have focused on this. The objectives of this project are 1- to describe and quantify the spatial and temporal activity of free-ranging dogs and foxes, and identify the anthropogenic and environmental factors that influence their presence near and within northern villages, 2- to quantify direct contacts and the potential for interactions between free-ranging dogs and foxes in order to better identify periods and areas of higher risk of rabies transmission, 3- to compare and contrast dog-fox activity and interactions between the two northern villages under study, and 4- to identify management methods to reduce opportunities for fox-dog interactions. To detect the presence of the two carnivores, we set up a network of automatic cameras near and within two typical northern villages, i.e., Kuujjuaq (near the tree line) and Inukjuak (> 100 km from the tree line). For each camera, different anthropogenic and environmental factors were evaluated (distance to the landfill, distance to the airport, density of dwellings, density of sled dogs, distance to streets, distance to water, vegetation index). Direct contacts and interaction index were calculated to assess the potential for interactions between foxes and free-roaming dogs. Interaction opportunities between foxes and dogs are more likely to occur at dawn and dusk during the months of October and November, and on the outskirts of both villages, particularly near sled dogs and slightly nearer to the landfill (KU) and the airport (IN). Red and Arctic foxes were observed in and around both villages, but red foxes were more frequently observed in Kuujjuaq (87% of observations) while Arctic foxes were more frequent in Inukjuak (74% of observations), which also reflects the biotic and abiotic particularities specific to each village. These results suggest that fox-dog contacts around and within the village are likely, posing a real risk of peri-domestic rabies transmission to dogs and humans, and possibly for other northern pathogens transmissible between wildlife and dogs. Nevertheless, interspecific direct contact events are rare and interaction opportunities are concentrated in time and space, which may help target preventive measures aimed at limiting transmission events. This study provides the first documentation on the activity of foxes and their interactions with dogs and humans in Arctic communities. Considering the potential risk-by-proximity described in our study, a “One Health” approach could be applied to prevent or lower fox-dog rabies transmission.
308

Asynchronous Event-Feature Detection and Tracking for SLAM Initialization

Ta, Tai January 2024 (has links)
Traditional cameras are most commonly used in visual SLAM to provide visual information about the scene and positional information about the camera motion. However, in the presence of varying illumination and rapid camera movement, the visual quality captured by traditional cameras diminishes. This limits the applicability of visual SLAM in challenging environments such as search and rescue situations. The emerging event camera has been shown to overcome the limitations of the traditional camera with the event camera's superior temporal resolution and wider dynamic range, opening up new areas of applications and research for event-based SLAM. In this thesis, several asynchronous feature detectors and trackers will be used to initialize SLAM using event camera data. To assess the pose estimation accuracy between the different feature detectors and trackers, the initialization performance was evaluated from datasets captured from various environments. Furthermore, two different methods to align corner-events were evaluated on the datasets to assess the difference. Results show that besides some slight variation in the number of accepted initializations, the alignment methods show no overall difference in any metric. Overall highest performance among the event-based trackers for initialization is HASTE with mostly high pose accuracy and a high number of accepted initializations. However, the performance degrades in featureless scenes. CET on the other hand shows mostly lower performance compared to HASTE.
309

Stereo vision and LIDAR based Dynamic Occupancy Grid mapping : Application to scenes analysis for Intelligent Vehicles / Cartographie dynamique occupation grille basée sur la vision stéréo et LIDAR : Application à l'analyse de scènes pour les véhicules intelligents

Li, You 03 December 2013 (has links)
Les systèmes de perception, qui sont à la base du concept du véhicule intelligent, doivent répondre à des critères de performance à plusieurs niveaux afin d’assurer des fonctions d’aide à la conduite et/ou de conduite autonome. Aujourd’hui, la majorité des systèmes de perception pour véhicules intelligents sont basés sur la combinaison de données issues de plusieurs capteurs (caméras, lidars, radars, etc.). Les travaux de cette thèse concernent le développement d’un système de perception à base d’un capteur de vision stéréoscopique et d’un capteur lidar pour l’analyse de scènes dynamiques en environnement urbain. Les travaux présentés sont divisés en quatre parties.La première partie présente une méthode d’odométrie visuelle basée sur la stéréovision, avec une comparaison de différents détecteurs de primitives et différentes méthodes d’association de ces primitives. Un couple de détecteur et de méthode d’association de primitives a été sélectionné sur la base d’évaluation de performances à base de plusieurs critères. Dans la deuxième partie, les objets en mouvement sont détectés et segmentés en utilisant les résultats d’odométrie visuelle et l’image U-disparité. Ensuite, des primitives spatiales sont extraites avec une méthode basée sur la technique KPCA et des classifieurs sont enfin entrainés pour reconnaitre les objets en mouvement (piétons, cyclistes, véhicules). La troisième partie est consacrée au calibrage extrinsèque d’un capteur stéréoscopique et d’un Lidar. La méthode de calibrage proposée, qui utilise une mire plane, est basée sur l’exploitation d’une relation géométrique entre les caméras du capteur stéréoscopique. Pour une meilleure robustesse, cette méthode intègre un modèle de bruit capteur et un processus d’optimisation basé sur la distance de Mahalanobis. La dernière partie de cette thèse présente une méthode de construction d’une grille d’occupation dynamique en utilisant la reconstruction 3D de l’environnement, obtenue des données de stéréovision et Lidar de manière séparée puis conjointement. Pour une meilleure précision, l’angle entre le plan de la chaussée et le capteur stéréoscopique est estimé. Les résultats de détection et de reconnaissance (issus des première et deuxième parties) sont incorporés dans la grille d’occupation pour lui associer des connaissances sémantiques. Toutes les méthodes présentées dans cette thèse sont testées et évaluées avec la simulation et avec de données réelles acquises avec la plateforme expérimentale véhicule intelligent SetCar” du laboratoire IRTES-SET. / Intelligent vehicles require perception systems with high performances. Usually, perception system consists of multiple sensors, such as cameras, 2D/3D lidars or radars. The works presented in this Ph.D thesis concern several topics on cameras and lidar based perception for understanding dynamic scenes in urban environments. The works are composed of four parts.In the first part, a stereo vision based visual odometry is proposed by comparing several different approaches of image feature detection and feature points association. After a comprehensive comparison, a suitable feature detector and a feature points association approach is selected to achieve better performance of stereo visual odometry. In the second part, independent moving objects are detected and segmented by the results of visual odometry and U-disparity image. Then, spatial features are extracted by a kernel-PCA method and classifiers are trained based on these spatial features to recognize different types of common moving objects e.g. pedestrians, vehicles and cyclists. In the third part, an extrinsic calibration method between a 2D lidar and a stereoscopic system is proposed. This method solves the problem of extrinsic calibration by placing a common calibration chessboard in front of the stereoscopic system and 2D lidar, and by considering the geometric relationship between the cameras of the stereoscopic system. This calibration method integrates also sensor noise models and Mahalanobis distance optimization for more robustness. At last, dynamic occupancy grid mapping is proposed by 3D reconstruction of the environment, obtained from stereovision and Lidar data separately and then conjointly. An improved occupancy grid map is obtained by estimating the pitch angle between ground plane and the stereoscopic system. The moving object detection and recognition results (from the first and second parts) are incorporated into the occupancy grid map to augment the semantic meanings. All the proposed and developed methods are tested and evaluated with simulation and real data acquired by the experimental platform “intelligent vehicle SetCar” of IRTES-SET laboratory.
310

Faculty Senate Minutes October 5, 2015

University of Arizona Faculty Senate 09 November 2015 (has links)
This item contains the agenda, minutes, and attachments for the Faculty Senate meeting on this date. There may be additional materials from the meeting available at the Faculty Center.

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