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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.
191

Using Camera-Traps to Evaluate the Relative Abundance of Predators and Prey on the Western Slope of the Panama Canal

Ashmore, Jordan Rivers 01 December 2009 (has links)
Little research has been conducted in the Republic of Panama concerning mammalian predator and prey populations. New Technologies such as remote camera-traps, allow researcher to efficiently monitor elusive wildlife species within dense tropical vegetation. The general goal of this study was to establish concrete evidence of the felid population in EcoParque Panama-a newly designated protected area adjacent to Panama City. The specific objective of the study was to estimate the relative abundance of predators and prey species in order to determine the feasibility of releasing more felids into the area that were to be removed from the Panama Canal Expansion Zone. Camera-traps were purposefully located in likely felid habitat and data were collected for approximately 5 months. Photographs were analyzed according to species and location captured, and abundances were established. Using SPSS and Statistix statistical software, tests for association between likely habitat for felids and time activity periods for prey species were conducted. EcoParque was found to have a robust prey population with relatively few predators. Felid predators present include the ocelot (Leopardus pardalis) and jaguarundi (Felis yaguarondi). Results suggest that felid carrying capacity has not been reached and additional individuals could be released into the area. This preliminary study lays the ground work for further research in EcoParque as well as the rest of Panama concerning predator and prey species relationships.
192

Filmpedagogik i en digital era : att sätta barnen och kameran i centrum / Film education in a digital era

Sternö, Linda January 2017 (has links)
Denna studie syftar till att undersöka filmpedagogik i en digital era, genom att sätta barnen ochkameran i centrum. Studien placerar sig inom forskningsområdet visuell kultur och är gjordmed hjälp av dubbla perspektiv; det konstnärliga/praktiska och det vetenskapliga/pedagogiska.Frågeställningarna undersöks med hjälp av ett filmat dokumentationsmaterial från en workshopmed barn, samt genom dokumentationsmaterial från en workshop inne i en camera obscura påKonstfacks vårutställning 2017. Workshopen i camera obscuran utgjorde även den gestaltandedelen av detta mastersarbete. Det empiriska materialet är insamlat genom metoden visuellperformativ etnografi. I analysen letar jag upp situationer där barnens agerande stör mig pånågot sätt, vilket blir en metod att hitta de konventioner inom filmpedagogiken jag villgenomlysa och utmana. Med hjälp av teoretiska verktyg från det posthumanistiska tänkandetanalyserar jag materialet. Resultaten från studien pekar på att en ny filmpedagogik, anpassadtill det digitala, skulle kunna utgå från barnen och drivas av barnens intresse och utforskandemed kameran, snarare än att barnen ska lära sig en fast norm för vad film är. Resultaten visarockså att genom att göra bildfenomenet som uppstår i camera obscura till en utgångspunkt förfilmpedagogiken kan synen på vad film är och kan vara idag utforskas vidare och därmedlösgöras från konventioner bundna till en analog teknik.
193

Evaluating the impacts of human-mediated disturbances on species’ behaviour and interactions

Frey, Sandra 27 August 2018 (has links)
Developing effective conservation strategies requires an empirical understanding of species' responses to human-mediated disturbances. Observable responses are typically limited to dramatic changes such as wildlife population declines or range shifts. However, preceding these obvious responses, more subtle responses may signal larger-scale future change, including changes in species' behaviours and interspecific interactions. Disturbance-induced shifts to species' diel activity patterns may disrupt mechanisms of niche partitioning along the 24-hour time axis, altering community structure via altered competitive interactions. I investigate the main questions and methods of analysis applicable to camera-trap data for furthering our understanding of temporal dynamics in animal communities. I apply these methods to evaluate the impacts of human-mediated disturbance on species' activity patterns and temporal niche partitioning in two separate studies, focusing on responses in the mammalian carnivore community. In the Canadian Rocky Mountain carnivore guild, species alter diel activities in relation to anthropogenic landscape development, although these shifts may be manifesting through indirect biotic effects instead of direct responses to human disturbance. Mesocarnivore species on a mixed-use landscape featuring anthropogenic land-use and introduced free-ranging dogs (Canis familiaris) shift activities in relation to spatiotemporal dog activity. Native carnivores partition diel activities differently on open landscapes of enhanced predation risk but abundant prey resources. Detecting shifts in species' temporal behaviours and competitive interactions may enable identification of potential precursors of population declines and shifting community assemblages, providing us with opportunities to pre-emptively manage against such biodiversity losses on human-modified landscapes. / Graduate
194

Dance/Video Mashup as a Choreographic Process

Johnston, Molly 29 September 2014 (has links)
This thesis document articulates the development of Dance/Video Mashup as a Choreographic Process. Prior to this movement thesis I determined a list of goals I would aim to achieve throughout the exploration of Dance/Video Mashup as a Choreographic Process. The goals aimed to develop a choreographic process that sampled movement from videos found online, create a website that documented the creative process of developing a screendance, realize an artistic need and develop clear guidelines for future choreographers. This document narrates and evaluates the creative process of developing guidelines for Dance/Video Mashup and clearly articulates the guidelines for future researchers and choreographers. The supplemental file attached allows readers to view the screendance, Somniloquies, created through Dance/Video Mashup as a Choreographic Process.
195

Fisheye Camera Calibration and Applications

January 2014 (has links)
abstract: Fisheye cameras are special cameras that have a much larger field of view compared to conventional cameras. The large field of view comes at a price of non-linear distortions introduced near the boundaries of the images captured by such cameras. Despite this drawback, they are being used increasingly in many applications of computer vision, robotics, reconnaissance, astrophotography, surveillance and automotive applications. The images captured from such cameras can be corrected for their distortion if the cameras are calibrated and the distortion function is determined. Calibration also allows fisheye cameras to be used in tasks involving metric scene measurement, metric scene reconstruction and other simultaneous localization and mapping (SLAM) algorithms. This thesis presents a calibration toolbox (FisheyeCDC Toolbox) that implements a collection of some of the most widely used techniques for calibration of fisheye cameras under one package. This enables an inexperienced user to calibrate his/her own camera without the need for a theoretical understanding about computer vision and camera calibration. This thesis also explores some of the applications of calibration such as distortion correction and 3D reconstruction. / Dissertation/Thesis / Masters Thesis Electrical Engineering 2014
196

Influência da injunção da base na fototriangulação de imagens obtidas com uma unidade de mapeamento móvel

Espinhosa, Dalila Rosa Souza [UNESP] 25 August 2006 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:22:26Z (GMT). No. of bitstreams: 0 Previous issue date: 2006-08-25Bitstream added on 2014-06-13T20:48:54Z : No. of bitstreams: 1 espinhosa_drs_me_prud.pdf: 812310 bytes, checksum: 523e8c58d62ab6b4c0194742e34aa362 (MD5) / Em geral, um sistema móvel de mapeamento é caracterizado por um veículo automotor com um par de vídeo-câmaras montado sobre seu teto e sensores de posicionamento e navegação, tais como receptores GPS e sensores inerciais (acelerômetros, giroscópios, hodômetros etc), embarcados no interior do veículo. O processo de mapeamento topográfico e/ou cadastral com base nestes sistemas móveis consiste em capturar imagens das vias de transporte, fazer a determinação da orientação das imagens por meio da combinação de técnicas de posicionamento geodésico e técnicas fotogramétricas, armazenar as imagens georreferenciadas em um banco de imagens e daí extrair feições de interesse e representá-las cartograficamente. Os resultados mostraram que a utilização da injunção da estéreo-base tem influência em aumentar a convergência das câmaras em aproximadamente 0,1º sexagesimal e não melhorou as estimativas das coordenadas dos pontos no espaço objeto em nível de significância de 5%, nem influenciou o cálculo dos parâmetros de orientação interior. Os testes realizados com observações de qualidade pixel e subpixel indicaram que o uso de medidas subpixel é recomendado. Por meio da determinação das diferenças dos ângulos de orientação das imagens, verifica-se que os eixos ópticos não estão realmente paralelos e ortogonais à estéreo-base, há uma pequena convergência (aproximadamente 0,5º sexagesimal) e não estão no mesmo plano (desvio de aproximadamente 0,8º sexagesimal). / In general, a land-based mobile mapping system is featured by a vehicle with a pair of video cameras mounted on its roof and positioning and navigation sensors such as GPS receivers and inertial sensors (accelerometers, gyros, odometers etc) loaded in the vehicle. The topographic and/or cadastral mapping process based on these mobile systems consists on capturing road images, determining the image orientation by geodetic and photogrammetric techniques, saving the georeferenced images in an image database and then extracting and mapping interest features. The results show that the stereo base constraint has influence on to increase camera convergence on 0.1 sexagesimal degree and improves but not significantly, in 5% level, the object point X coordinate estimation, and has minor influence on the interior orientation parameters. The experiments with pixel and subpixel observation indicated that subpixel quality is recommended. Finally, considering the differences of the image orientation angles, it is verified that the optical axes are not truly parallel and orthogonal to the stereo base. In other words, there is a little convergence (0.5 sexagesimal degree) between the optical axes and they are not in the same plain (0.8 sexagesimal degree deviation).
197

Influência da injunção da base na fototriangulação de imagens obtidas com uma unidade de mapeamento móvel /

Espinhosa, Dalila Rosa Souza. January 2006 (has links)
Orientador: João Fernando Custódio da Silva / Banca: Jorge Luís Nunes e Silva Brito / Banca: Aluir Porfírio Dal Poz / Resumo: Em geral, um sistema móvel de mapeamento é caracterizado por um veículo automotor com um par de vídeo-câmaras montado sobre seu teto e sensores de posicionamento e navegação, tais como receptores GPS e sensores inerciais (acelerômetros, giroscópios, hodômetros etc), embarcados no interior do veículo. O processo de mapeamento topográfico e/ou cadastral com base nestes sistemas móveis consiste em capturar imagens das vias de transporte, fazer a determinação da orientação das imagens por meio da combinação de técnicas de posicionamento geodésico e técnicas fotogramétricas, armazenar as imagens georreferenciadas em um banco de imagens e daí extrair feições de interesse e representá-las cartograficamente. Os resultados mostraram que a utilização da injunção da estéreo-base tem influência em aumentar a convergência das câmaras em aproximadamente 0,1º sexagesimal e não melhorou as estimativas das coordenadas dos pontos no espaço objeto em nível de significância de 5%, nem influenciou o cálculo dos parâmetros de orientação interior. Os testes realizados com observações de qualidade pixel e subpixel indicaram que o uso de medidas subpixel é recomendado. Por meio da determinação das diferenças dos ângulos de orientação das imagens, verifica-se que os eixos ópticos não estão realmente paralelos e ortogonais à estéreo-base, há uma pequena convergência (aproximadamente 0,5º sexagesimal) e não estão no mesmo plano (desvio de aproximadamente 0,8º sexagesimal). / Abstract: In general, a land-based mobile mapping system is featured by a vehicle with a pair of video cameras mounted on its roof and positioning and navigation sensors such as GPS receivers and inertial sensors (accelerometers, gyros, odometers etc) loaded in the vehicle. The topographic and/or cadastral mapping process based on these mobile systems consists on capturing road images, determining the image orientation by geodetic and photogrammetric techniques, saving the georeferenced images in an image database and then extracting and mapping interest features. The results show that the stereo base constraint has influence on to increase camera convergence on 0.1 sexagesimal degree and improves but not significantly, in 5% level, the object point X coordinate estimation, and has minor influence on the interior orientation parameters. The experiments with pixel and subpixel observation indicated that subpixel quality is recommended. Finally, considering the differences of the image orientation angles, it is verified that the optical axes are not truly parallel and orthogonal to the stereo base. In other words, there is a little convergence (0.5 sexagesimal degree) between the optical axes and they are not in the same plain (0.8 sexagesimal degree deviation). / Mestre
198

The standard plenoptic camera : applications of a geometrical light field model

Hahne, Christopher January 2016 (has links)
The plenoptic camera is an emerging technology in computer vision able to capture a light field image from a single exposure which allows a computational change of the perspective view just as the optical focus, known as refocusing. Until now there was no general method to pinpoint object planes that have been brought to focus or stereo baselines of perspective views posed by a plenoptic camera. Previous research has presented simplified ray models to prove the concept of refocusing and to enhance image and depth map qualities, but lacked promising distance estimates and an efficient refocusing hardware implementation. In this thesis, a pair of light rays is treated as a system of linear functions whose solution yields ray intersections indicating distances to refocused object planes or positions of virtual cameras that project perspective views. A refocusing image synthesis is derived from the proposed ray model and further developed to an array of switch-controlled semi-systolic FIR convolution filters. Their real-time performance is verified through simulation and implementation by means of an FPGA using VHDL programming. A series of experiments is carried out with different lenses and focus settings, where prediction results are compared with those of a real ray simulation tool and processed light field photographs for which a blur metric has been considered. Predictions accurately match measurements in light field photographs and signify deviations of less than 0.35 % in real ray simulation. A benchmark assessment of the proposed refocusing hardware implementation suggests a computation time speed-up of 99.91 % in comparison with a state-of-the-art technique. It is expected that this research supports in the prototyping stage of plenoptic cameras and microscopes as it helps specifying depth sampling planes, thus localising objects and provides a power-efficient refocusing hardware design for full-video applications as in broadcasting or motion picture arts.
199

Ecological study of the ocelote (Leopardus pardalis) using the camera trap technique, in Las Piedras Region, Madre de Dios-Peru / Estudio ecológico del ocelote (Leopardus pardalis) utilizando el método de cámaras trampa en el distrito de Las Piedras, Madre de Dios - Perú

Castagnino Vera, Romina 10 April 2018 (has links)
The study focuses in the ecology and conservation of the ocelot (Leopardus pardalis) in the conservation and tourism concession owned by the ARCC. The study site is 11 000 hectares and it is located in the Las Piedras Region, north of Tambopata province, Madre de Dios. Camera traps were used to monitor the ocelot population during a 7-month period (from August 2012 to February 2013), divided in 9 rounds were 73 cameras were installed. The camera traps found 8 independent ocelots, from which only 3 (A1, A3 and A6) were recaptured in more than one occasion. The study did a capture-recapture analysis. The distance traveled by the ocelots from a capture to a recapture site was used to estimate the effective sampled area using the Mean Maximum Distance Moved - MMDM and Half MMDM. The methods yielded a density of 70 individuals/100km2 and 180 individuals/100km2, with full MMDM and Half MMDM, respectively. The study also analyzed the camera trap capture probability with PRESENCE software. Using a closed CR analysis followed by a model of constant capture probability, it yielded a capture probability rate of 0,3 (SE 0,0567). Finally, the ocelot’s habitat preference was also studied using a combination of satellite imagery and GIS software. It was found that these animals frequently use transects aimed for tourists, prefer sites near water and that they avoid bamboo forests. / Este estudio trata sobre la ecología y conservación del ocelote (Leopardus pardalis), en la concesión de conservación y ecoturismo del albergue Amazon Research and Conservation Center - ARCC. El área de estudio, de 11 000 hectáreas, se encuentra ubicada en el distrito de Las Piedras, norte de la provincia de Tambopata, departamento de Madre de Dios, Perú. Se utilizaron cámaras trampa para monitorear la población del felino en un período de siete meses (de agosto de 2012 a febrero de 2013), dividido en nueve rondas donde se instalaron 73 cámaras en total. Fueron ocho ocelotes independientes los identificados, de los cuales solo tres (A1, A3 y A6) fueron recapturados visualmente en más de una ocasión. Se realizó un análisis de captura-recaptura. Las distancias recorridas por los ocelotes entre captura y recaptura se utilizaron para estimar el área efectiva de muestreo usando el método del Promedio de la Máxima Distancia Recorrida - MMDM y Mitad del MMDM. Los métodos dieron como resultado una densidad poblacional de 700 ocelotes/100 km2 y 180 ocelotes/100 km2 con MMDM y Mitad del MMDM, respectivamente. Por otro lado, se analizó la probabilidad de captura de las cámaras trampa con el software PRESENCE. Utilizando un análisis poblacional cerrado y un modelo constante, se halló una detección por ronda de 0,3 (SE 0,0567). Finalmente, también se evaluó la preferencia de hábitat de los ocelotes a través de imágenes satélite. Se halló que la mayoría de los felinos usan transectos turísticos, que prefieren las llanuras aluviales cercanas a las riberas de los ríos y cochas, y que evitan los pantanos.
200

Dosimetria por cintilação utilizando imagens adquiridas com câmera digital / Scintillation dosimetry using images acquired with digital camera

Fernanda Guzzi Biagioni 25 May 2018 (has links)
A utilização de detectores de radiação é de imensa importância na área de dosimetria, pois permite a quantificação da dose absorvida no meio. Uma técnica interessante para esta finalidade é o uso de detectores por cintilação. Estudos recentes com cintiladores plásticos e líquidos demonstraram a viabilidade do uso de detecção de cintilação por uma câmera digital com sensor CCD ou CMOS. Desse modo, este trabalho tem como objetivo desenvolver um dosímetro cintilador de baixo custo para viabilidade de seu uso e, de um sistema de detecção de cintilação através de uma câmera digital, para que assim pudesse ser realizada sua caracterização dosimétrica. O sistema dosimétrico foi construído a partir de um cintilador líquido a base de antraceno. Dosimetricamente verificou-se uma linearidade de resposta para a dose de 0,1 a 25,53 Gy, para a taxa de dose de 6,66 Gy/min e uma pequena diminuição da sensibilidade do dosímetro quando aumentada a taxa de dose de irradiação. Com relação à dependência energética, foi verificado um aumento na sensibilidade do dosímetro de 10,8% ao se variar a energia de 100 a 160 kVp. Quando comparado a um cintilador comercial, apresentou uma intensidade de sinal reduzida e, em uma análise de reprodutibilidade, obteve-se uma variação máxima de 2% em relação a repetição de uma mesma medida. O cintilador líquido apresentou baixa estabilidade pré e pós-irradiação, com uma variação de cor e redução do sinal ao decorrer dos dias. Para medidas bidimensionais o sistema montado mostrou-se promissor, uma vez que em medidas de deposição de dose com a profundidade para várias energias de feixes, verificou-se o aumento da penetração da radiação com o aumento da energia do feixe e as medidas de penumbra de um feixe parcialmente blindado com 2 mmPb apresentaram um valor de 1,79 cm, considerando o tipo de tubo gerador e blindagem utilizada. Por toda a caracterização realizada o sistema dosimétrico mostrou-se aplicável para dosimetria, desde que operado considerando as características apresentadas. / The utilization of radiation detector is important in the dosimetric area, because it allow the quantification of absortion dose in the medium. An interesting tehnique for this finalitypurpose is the use of scintillation detector. Recent studies with plastic scintillators and liquid scintillators have demonstrated the feasibility of using scintillation detection by a digital camera with CCD or CMOS sensors. Thus, this study is the intent to develop a low-cost scintillation dosimeter for the feasibility of its use and detection scintillation system through by a digital camera, with the finality of dosimetric characterization. The dosimetric system was constructed from using liquid scintilator based anthracene. A linearity dose response between 0.1 to 25.53 Gy was found for the dose rate of 6.66 Gy/min and the dosimeter sensibility was decreased when the dose rate increased. When varied the energy from 100 to 160 kVp, was verified an increased of 10.8% in the dosimeter sensibility, due the energy dependence. When compared to a commercial dosimeter, it shows signal intensity decreased and, the study of reproducibility, a maximum variation of 2% was obtained in relation to the repetition of the same measure. The liquid scintillator presented low stability before and after irradiation, with a color variation and signal reduction over the days. For two-dimensional measurements the assembled system proved to be promising, since in dose deposition measurements with the depth for several beam energies, the penetration of the radiation was increased with the increase of the beam energy and the penumbra measurements of a narrow beam with 2mmPb presented a value of 1.79 cm, considering the type of generator tube and narrow used. Throughout the characterization carried out the dosimetric system proved to be applicable for dosimetry, if operated considering the characteristics presented.

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