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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.
11

Zpracování snímků pořízených pomocí UAV / Processing of images taken from UAV

Ptáček, Ondřej January 2014 (has links)
This diploma thesis deals with the processing and evaluation of the pictures taken by unmanned aerial vehicles - UAV. The introductory part is devoted to the definition, use, applications and types of UAV especially for photogrammetric purposes. Also the software equipment is described, including a description and examples of several types of possible outcomes. Further the measurements, computational works and process of elaboration in used software programs are described. Achieved outcomes of elaboration are also presented. In conclusion, the overall evaluation and assessment of the results of measurement is done of set of points.
12

Identifiera löv i skogar – Att lära en dator känna igen löv med ImageAI

Nordqvist, My January 2019 (has links)
A current field of research today is machine learning because it can simplify everyday life for human beings. A functioning system that has learned specific tasks can make it easier for companies in both cost and time. A company who want to use machine learning is SCA, who owns and manages forests to produce products. They have a need to automate forest classification. In order to evaluate forests, and to plan forestry measures, the proportion of leafy tree that is not used in production must be determined. Today, manual work is required of people who have to investigate aerial photos to classify the tree types. This study investigates whether it is possible, through machine learning, to teach a computer to determine whether it is leaf or not in photographs. A program is constructed with the library ImageAI which receives methods for training and predicting information in images. It examines how the choice of neural network and the number of images affects the safety of the models and how reliable the models can be. Exercise time and hardware are also two factors that are investigated. The result shows that the neural network ResNet delivers the safest results and the more images the computer exercises, the safer the result. The final model is a ResNet model that has trained on 20,000 images and has 79,0 percent security. Based on 50 samples, the mean value for safety is 90,5 percent and the median is 99,6 percent. / Maskininlärning är idag ett aktuellt forskningsområde som kan förenkla vardagen för oss människor. Ett fungerande system som har lärt sig specifika uppgifter kan underlätta för företag i både kostnad och tid. Ett företag som vill använda maskininlärning är SCA, som äger och förvaltar skog för att producera produkter. De har behov av att automatisera klassificering av skog. För att värdera skogar, samt planera skogsåtgärder, måste andelen lövträd som inte används i produktionen bestämmas. Idag krävs det manuellt arbete av personer som måste undersöka flygfoton för att klassificera trädtyperna. Denna studie undersöker om det är möjligt, via maskininlärning, att lära en dator avgöra om det är löv eller inte i ortofoton. Ett program konstrueras med biblioteket ImageAI som erhåller metoder för att träna och förutsäga information i bilder. Det undersöks hur valet av neuralt nätverk och antalet bilder påverkar säkerheten för modellerna samt hur tillförlitlig modellerna kan bli. Träningstid och hårdvara är också två faktorer som studeras. Resultatet visar att neurala nätverket ResNet levererar säkrast resultat och desto fler bilder datorn tränar på, desto säkrare blir resultatet. Den slutgiltiga modellen är en ResNet-modell som tränat på 20 000 bilder och har 79,0 procents säkerhet. Utifrån 50 stickprov är medelvärdet för säkerheten 90,5 procent och medianen 99,6 procent.
13

Development of a digital orthophoto generation system for analysis of forest canopy dynamics

ITAYA, Akemi, 板谷, 明美, YAMAMOTO, Shin-Ichi, 山本, 進一 12 1900 (has links) (PDF)
農林水産研究情報センターで作成したPDFファイルを使用している。
14

Datové sady a mapové produkty resortu ČÚZK a jejich využitelnost pro pozemkové úpravy / Data sets and map products of the State Administration of Land Surveying and Cadastre and their usability for land consolidation.

HONETSCHLÄGER, Petr January 2018 (has links)
The aim of the master's thesis is to describe the map products of the State Administration of Land Surveying and Cadastre and their applicability in planning the Land consolidation. This master's thesis consists of two parts. In literary research are explained basic terms and describe all the map series, administered by the State Administration of Land Surveying and Cadastre. There are described contents and possibilities of using individual maps, including their availability. In practical part of master's thesis are describes the maps used in the Land consolidation from different viewpoints.
15

Uso de veículos aéreos não tripulados para mapeamento e avaliação de erosão urbana / Use of unmanned arial vehicles (UAV) for mapping and evaluating urban erosion (in Goiás state, Brazil)

Rodrigues , Avilmar Antonio 25 November 2016 (has links)
Submitted by Luciana Ferreira (lucgeral@gmail.com) on 2016-12-27T11:27:00Z No. of bitstreams: 2 Dissertação - Avilmar Antonio Rodrigues - 2016.pdf: 13580117 bytes, checksum: 2b78a395b4bd955f8d72e83399bcc578 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Approved for entry into archive by Luciana Ferreira (lucgeral@gmail.com) on 2016-12-27T11:27:20Z (GMT) No. of bitstreams: 2 Dissertação - Avilmar Antonio Rodrigues - 2016.pdf: 13580117 bytes, checksum: 2b78a395b4bd955f8d72e83399bcc578 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2016-12-27T11:27:20Z (GMT). No. of bitstreams: 2 Dissertação - Avilmar Antonio Rodrigues - 2016.pdf: 13580117 bytes, checksum: 2b78a395b4bd955f8d72e83399bcc578 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2016-11-25 / This research aimed to evaluate the use of Unmanned Aerial Vehicle (UAV) as a platform for taking aerial photographs for mapping erosion planialtimetric located in urban areas. In addition, we evaluated the need to use or not to field control points for the generation of Digital Surface Model (DSM) and ortomosaico as tools to evaluate the erosive process. Despite the wide variation in attitude of aerial photographs that make up the aerophotogrammetric block arising from the instability of the UAV, it was possible to generate the MDS and ortomosaico with or without control points. This research was conducted in two urban erosions located in Goiania in Sector Fonte Nova in the stream of grass and the other in Silvânia called foot-washing. Whole generation of MDS, Digital Surface Model (MDT) and ortomosaico were performed in Agisoft PhotoScan program in semi-automatic processing, if used control points, or automatic without control points. The ortomosaicos generated without control points presented rotation, translation and scale of different generated with support. In addition, MDS generated without control points showed elevation or lowering of the reference surface with respect to the generated control, it is emphasized that these discrepancies are not constant. When performing automatic conversion of MDS to MDT, it was realized that the program was not able to eliminate the shrub vegetation located within the erosion. The vegetation or tree, shrub or undergrowth (grass) prevents proper limitation of erosion to the volume calculation. But unlike the MDS generated between two distinct epochs identifies the changes in the interval of time in areas without vegetation. The use of control points was essential to ensure the orientation, scale and the reference plane in the products generated from aerial photographs and thus evaluate the changes. Anyway, the UAV can be used as a platform for taking aerial photographs for generating cartographic products that enable the mapping and evaluation of erosions. / Esta pesquisa teve por objetivo avaliar a utilização do Veículo Aéreo Não Tripulado (VANT) como plataforma para a tomada de fotografias aéreas para o mapeamento planialtimétrico de erosão situada em zona urbana. Além disso, analisou-se a necessidade de utilização ou não de pontos de controle de campo para a geração de Modelo Digital de Superfície (MDS) e ortomosaico como instrumentos para examinar o processo erosivo. Apesar da grande variação da atitude da aeronave durante a obtenção das fotografias aéreas que compõem o bloco aerofotogramétrico, foi possível gerar o MDS e o ortomosaico com ou sem pontos de controle. Este estudo foi realizado em duas erosões urbanas, uma situada em Goiânia-GO, no Setor Fonte Nova/Córrego do Capim, e a outra em Silvânia-GO, denominada de Lava-Pés. Toda a geração dos MDS, Modelo Digital de Terreno (MDT) e ortomosaico foram realizados no programa Agisoft PhotoScan, em processamento semiautomático (i.e., com pontos de controle) e automático (i.e., sem pontos de controle). Os ortomosaicos gerados sem pontos de controle apresentaram rotação, translação e escala diferente dos gerados com apoio. Ademais, os MDS gerados sem pontos de controle apresentaram elevação ou rebaixamento da superfície de referência em relação aos gerados com controle. Ressalta-se, ainda, que essas discrepâncias não foram constantes. Ao realizar a conversão automática do MDS para o MDT, percebeu-se que o programa não foi capaz de eliminar a vegetação arbustiva localizada no interior da erosão. As vegetações arbórea, arbustiva ou rasteira (gramíneas) impedem a correta delimitação da erosão para o cálculo do volume. Porém, a diferença dos MDS gerados entre duas épocas distintas propicia identificar as alterações ocorridas nesse intervalo de tempo nas regiões sem cobertura vegetal. O uso de pontos de controle foi essencial para garantir a orientação, a escala e o plano de referência nos produtos gerados a partir das fotografias aéreas e, assim, avaliar as modificações da erosão. Por fim, o VANT pode ser utilizado como plataforma para a tomada de fotografias aéreas para gerar produtos cartográficos que possibilitem o mapeamento e as avaliações das erosões, sobretudo em áreas urbanas.
16

Utvärdering av lägesosäkerheter i ortofoton framtagna med hjälp av DJI Phantom 4 RTK / Evaluation of position uncertainties in orthophotos developed with a DJI Phantom 4 RTK

Larsson, Johan, Stark, Marcus January 2019 (has links)
Flygfotografering med Unmanned Aircraft System (UAS) är i jämförelse med traditionell fotogrammetri effektivare, billigare och säkrare vilket har medfört att denna teknik föredras av många aktörer. Ett tidskrävande arbete som varit svårt att kringgå är att etablera flygsignaler på marken som används för att georeferera och kontrollera flygbilderna med. Under 2018 presenterade UAS-tillverkaren DJI sin nya quadcopter med integrerad Real-Time Kinematic (RTK)-modul. I samband med detta kan kontinuerliga och noggranna positioner levereras via Nätverks-RTK (NRTK) och behovet av markstödpunkter reduceras. I denna studie undersöktes lägesosäkerheterna i plan för ortofoton som framställdes med hjälp av en DJI Phantom 4 RTK där flygbilderna georefererades med begränsat antal eller utan markstödpunkter. Lägesosäkerheterna beräknades och kontrollerades enligt Handbok i mät- och kartfrågor (HMK) – Ortofoto, vilket är ett stöddokument inom ämnet. Vid framställning av ett ortofoto krävs även en digital terrängmodell (DTM) eller en digital ytmodell (Digital Surface Model, DSM) och kvaliteten av denna har stor inverkan på ortofotots kvalitet. I denna studie kontrollerades och utvärderades därför en del av den DSM som användes vid ortofotoframställning för respektive uppsättning enligt den tekniska specifikationen SIS-TS 21144:2016. Resultatet från studien visar att ett ortofoto går att framställas utan markstödpunkter och samtidigt klara kraven på specificerad lägesosäkerhet enligt HMK-standardnivå 3. Den sammanlagda lägesosäkerheten beräknades till 0,029 m vilket är 5 mm högre i jämförelse med ett ortofoto som baserats på traditionell georefereringsmetod, dvs. med markstödpunkter. Kravet på kvalitet i höjddata uppfylldes också för ortofotoframställning trots att en systematisk effekt i höjd uppkom. Denna effekt påverkade inte ortofotots koordinater i plan då standardosäkerheterna i höjd var låga. Resultatet visade att om två markstödpunkter adderades i vardera änden av området, kunde de systematiska effekterna i höjd minimeras och det var då möjligt att skapa en DSM som uppfyller kraven för detaljprojektering (noggrannhetsklass 1–3) enligt SIS-TS 21144:2016. / Aerial photography with UAS is in comparison with traditional photogrammetry more efficient, cheaper and safer which has led to this technology being preferred by many performers. A time-consuming job that has been difficult to avoid is to establish signals at the ground that are used for georeferencing and evaluate the results. In 2018, the UAS manufacturer DJI presented its new quadcopter with integrated Real-Time Kinematic (RTK) module. This allows continuous and accurate positions delivered via Network RTK (NRTK) and the need of ground control points can be reduced. In this study, investigations of the position uncertainties in orthophotos produced using a DJI Phantom 4 RTK carried out where the aerial images were georeferenced with limited numbers or without ground control points. The position uncertainties were calculated and controlled according to the Swedish HMK – Ortofoto (Orthophoto) which is a document within the subject. When producing an orthophoto, a digital terrain model (DTM) or a digital surface model (DSM) is also required and the quality of this has a great impact on the result. Therefore, a part of the DSM used for orthophoto production for each set was checked and evaluated according to the Swedish technical specification, SIS-TS 21144:2016. The result of the study shows that an orthophoto can be produced without ground control points and at the same time meet the requirements for specified position uncertainty according to HMK standard level 3. The total position uncertainty was calculated to be 0,029 m, which is 5 mm higher compared to the orthophoto based on the traditional georeferencing method, i.e. with ground control points. The requirement for quality in height data was also met for orthophoto production even though a systematic effect in height occurred. This effect did not affect the plane coordinates in the orthophoto because of the low standard uncertainties in height. The result showed that if two ground control points were added at each end of the area, the systematic effects were minimized, and it was possible to produce a DSM that fulfils the requirements for accuracy class 1-3 according to SIS-TS 21144:2016.
17

Vyhodnocení snímků pořízených pomocí UAV / Evaluation of data captured by UAV

Martináková, Veronika January 2018 (has links)
The master´s thesis deals with the application of unmanned aerial vehicle (UAV) in photogrammetry and mapping. The first part describes the UAV that was used for imaging, legislative restrictions resulting from its operations, planning and realization of the flight. The second part of this thesis is focused on processing results, especially on evaluation the accuracy of the results gained by UAV with and without a GNSS module. The data are evaluated in the 3rd accuracy rating class (ČSN 01 3410). The theoretical principles are explained as well. The main aim of the thesis is to demonstrate the effective use of the GNSS module Emlid Reach and the unmanned aerial vehicle in geodesy.
18

Žemės paėmimo visuomenės poreikiams įtakos žvyrkelių rekonstrukcijos kainai VĮ „Telšių regiono keliai“ veiklos zonoje vertinimas / Evaluation of the effect of taking of land for public needs on the price of the gravel roads reconstruction in the state enterprice „Telšių regiono keliai“ activity area

Lašinytė, Asta 13 June 2005 (has links)
The final master‘s work analyzes problems which occur or may occur due to taking the land for public needs when implementing the program of asphalt works on gravel roads in the area of activity of state enterprise „Telšių regiono keliai“. A research of sections of gravel roads intended for reconstruction and included into the program of maintenance and expansion of public highways for 2002–2015 was carried out, in the course of which a road plan was projected following norms of road engineering and the extent of taking the land for public needs was evaluated. Recommendations regarding the expedience of taking the land for road lane when implementing the program of asphalt works on gravel roads in the area of activity of state enterprise „Telšių regiono keliai“ were rendered.

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