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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.
1

En utredning av tekniken "mobile mapping" i kommunal verksamhet

Parianos, Andreas, Dahlqvist, Tobias January 2010 (has links)
<p>This thesis work is intended to analyze whether the municipalities has a need for the new technology of mobile mapping.</p><p>Mobile mapping consists of the technologies of laser scanning, photographing and positioning of streets and roads in city environment and in the countryside. When these technologies are operating together a georeferenced three-dimensional image model is created, which has specific coordinates that states its position on the surface of the earth. Thanks to the laser scanning process even measuring can be performed in this model.</p><p>The municipal sector consists of many different departments which use visual spatial information. These departments are an interesting target group for this system. Specific departments within the municipal sector, which we considered were the most suitable, have been selected. Individuals within these departments have replied to a <em>questionnaire</em> where several statements were given. The statements are constructed so that the replies that are received as much as possible describe the need for this new technology. In addition to the <em>questionnaire</em> a number of telephone- and in-depth interviews have been done in purpose of creating a basis which is as solid as possible.</p><p>The results that have been obtained indicate that there is a rather considerable demand for the technology. The majority of the asked professions have given replies which hint that they would appreciate visual measurable spatial information in accurate and detailed 3D-models. The telephone interviews have pointed in this direction as well.</p><p>Since a municipality is organized of a large number of departments which each have a need for the technology, a reference can be made to the expression “many a little makes a mickle”. In other words, the municipal need for the technology is considerable since many different units find their own uses for mobile mapping.</p><p>We have after this investigation obtained a result which implies that mobile mapping would be a good investment for the municipal sector.</p>
2

En utredning av tekniken "mobile mapping" i kommunal verksamhet

Parianos, Andreas, Dahlqvist, Tobias January 2010 (has links)
This thesis work is intended to analyze whether the municipalities has a need for the new technology of mobile mapping. Mobile mapping consists of the technologies of laser scanning, photographing and positioning of streets and roads in city environment and in the countryside. When these technologies are operating together a georeferenced three-dimensional image model is created, which has specific coordinates that states its position on the surface of the earth. Thanks to the laser scanning process even measuring can be performed in this model. The municipal sector consists of many different departments which use visual spatial information. These departments are an interesting target group for this system. Specific departments within the municipal sector, which we considered were the most suitable, have been selected. Individuals within these departments have replied to a questionnaire where several statements were given. The statements are constructed so that the replies that are received as much as possible describe the need for this new technology. In addition to the questionnaire a number of telephone- and in-depth interviews have been done in purpose of creating a basis which is as solid as possible. The results that have been obtained indicate that there is a rather considerable demand for the technology. The majority of the asked professions have given replies which hint that they would appreciate visual measurable spatial information in accurate and detailed 3D-models. The telephone interviews have pointed in this direction as well. Since a municipality is organized of a large number of departments which each have a need for the technology, a reference can be made to the expression “many a little makes a mickle”. In other words, the municipal need for the technology is considerable since many different units find their own uses for mobile mapping. We have after this investigation obtained a result which implies that mobile mapping would be a good investment for the municipal sector.
3

Jämförelse mellan Scheimpflug imaging och anterior segment OCT i mätning av Corneal tjocklek.

Fournstedt, Daniel January 2015 (has links)
Purpose: The purpose of this study was to compare corneal thickness measured both centrally and midperipherally, between two instruments using different measuring principles. The study also looked at correlation between corneal thickness and intraocular pressure (IOP). Methods: Central and midperipheral corneal thickness was measured on the right eyes of 31 subjects with two different instruments. Instruments were Scheimpflug-camera from Bon Sirius and an AS/OCT from Optos. Measurements were taken on central cornea (CCT) and midperipheral (nasal (NCT), temporal (TCT), superior (SCT) and inferior (ICT)) at a distance of 1.75 mm from the apex. Mean age of the subjects was 23.6 ± 4.5 years. (19-44 years). A CT-80A non-contact tonometer (NonCT) from Topcon was used to measure the intraocular pressure (IOP). Results: A mean-value for central corneal thickness was calculated to 542.4 µm and 540.4 µm for Bon Sirius and AS/OCT repectively. Remaining measured points had mean-values for corneal thickness of, NCT: 577.7 µm &amp; 558.5 µm. TCT: 555.0 µm &amp; 545.2 µm. SCT: 585.7 µm &amp; 554.5 µm. ICT: 563.0 µm &amp; 548.9 µm, respectively. Mean-difference for CCT was 2.4 µm and it showed a significant difference between the two instruments with a p-value of 0.007. Remaining measured points all showed a significant difference of p&lt;0.05. NCT: 19.2 µm. TCT: 9.8 µm. SCT: 31 µm. ICT: 14 µm. A correlation between IOP and CCT measured in both Sirius and AS/OCT was positive with r = 0.7 and p&lt;0.05. Conclusion: The results showed that Sirius gives higher values for corneal thickness then ASOCT in all five measurement points. The results show that these instruments can be used interchangeably when measuring central corneal thickness. However, caution should be used when measuring midperipheral corneal thickness as the there is a significant differences between these two instruments.
4

Understanding Solar Cell Contacts Through Simulations

January 2020 (has links)
abstract: The maximum theoretical efficiency of a terrestrial non-concentrated silicon solar cell is 29.4%, as obtained from detailed balance analysis. Over 90% of the current silicon photovoltaics market is based on solar cells with diffused junctions (Al-BSF, PERC, PERL, etc.), which are limited in performance by increased non-radiative recombination in the doped regions. This limitation can be overcome through the use of passivating contacts, which prevent recombination at the absorber interfaces while providing the selectivity to efficiently separate the charge carriers generated in the absorber. This thesis aims at developing an understanding of how the material properties of the contact affect device performance through simulations.The partial specific contact resistance framework developed by Onno et al. aims to link material behavior to device performance specifically at open circuit. In this thesis, the framework is expanded to other operating points of a device, leading to a model for calculating the partial contact resistances at any current flow. The error in calculating these resistances is irrelevant to device performance resulting in an error in calculating fill factor from resistances below 0.1% when the fill factors of the cell are above 70%, i.e., for cells with good passivation and selectivity. Further, silicon heterojunction (SHJ) and tunnel-oxide based solar cells are simulated in 1D finite-difference modeling package AFORS-HET. The effects of material property changes on device performance are investigated using novel contact materials like Al0.8Ga0.2As (hole contact for SHJ) and ITO (electron contact for tunnel-oxide cells). While changing the bandgap and electron affinity of the contact affect the height of the Schottky barrier and hence contact resistivity, increasing the doping of the contact will increase its selectivity. In the case of ITO, the contact needs to have a work function below 4.2 eV to be electron selective, which suggests that other low work function TCOs (like AZO) will be more applicable as alternative dopant-free electron contacts. The AFORS-HET model also shows that buried doped regions arising from boron diffusion in the absorber can damage passivation and decrease the open circuit voltage of the device. / Dissertation/Thesis / Masters Thesis Materials Science and Engineering 2020
5

Testování výškové přesnosti přijímačů GNSS RTK / Testing of height precision of GNSS RTK receivers

Sládek, Miroslav January 2016 (has links)
he main subject of this thesis is accuracy testing of three GNSS RTK receivers – Trimble R4, Leica 1200, Topcon GRS-1. It is an outdoor research using different correction types provided by CZEPOS and Trimble.
6

Construcción de Obras de Arte en el Corredor Vial Interoceánico Sur Perú – Brasil Tramo 3: Puente Inambari – Iñapari. EJECUCIÓN: Enero 2008 – Enero 2010

Espinoza Garay, Ethel Marcos January 2010 (has links)
El informe describe la Construcción de Obras de Arte en el Corredor Vial Interoceánico Sur Perú – Brasil Tramo 3: Puente Inambari en la Región Madre de Dios límite con Cuzco, hasta la ciudad fronteriza Iñapari con Brasil. En las obras de arte que menciono: Defensa Ribereña, Cunetas de Drenaje revestida en concreto y en césped respectivamente, Cuneta de Drenaje Urbano, Veredas Urbanas, Otras Obras de Arte (Pases Vehiculares, Pases Peatonales, Dispositivos de Amortiguamiento y Encausamiento de Alcantarillas); se define cada una de ellas, los materiales que se utilizan, y se explica el proceso constructivo. Se ve la importancia de la utilización de equipos de última generación en la topografía (estación total, GPS) y en el estudio de suelos (densímetro nuclear), entre otros, haciendo uso además de programas de computación asociados a estos. Además se hace una descripción del monitoreo de los trabajos realizados, supervisión de campo, programación e informe, reuniones semanales de coordinación y por último se hace mención al departamento de Seguridad y Salud que tienen el objetivo principal de garantizar las condiciones de seguridad y salvaguardar la vida, la integridad física y bienestar de los trabajadores en general. The report describes the Construction Works of Art in South Interoceanic Highway Peru - Brazil Section 3: Bridge Inambari in the Madre de Dios region bordering Cuzco, to the border town with Brazil Iñapari. In works of art that I mention: Riverfront Defense, Drainage Ditches lined with concrete and grass respectively Cuneta Urban Drainage, Urban Trails, Other Works of Art (Vehicle Passes, Passes Pedestrian, damping devices and Sewer Indictment) defined each of them, the materials used, and explains the construction process. We see the importance of using the latest equipment in the topography (total station, GPS) and the study of soils (nuclear densimeter), among others, also using computer programs associated with them. Besides a description of monitoring the work, field supervision, scheduling and reporting, weekly coordination meetings, and finally referred to the Health and Safety department with the primary aim of ensuring the security and safeguarding life, physical integrity and welfare of workers in general.
7

Mobilní mapování / Mobile Mapping

Manda, David January 2013 (has links)
The aim of this thesis is introduce the mobile mapping system IP-S2, which is using by company GEODIS BRNO, and perform data collection by this system. Measure the identical points, determine their coordinates and compare with coordinates obtained by mobile mapping system. The conclusion of this thesis is focused on testing the accuracy of the mobile mapping system.
8

OCT (Optical Coherense Tomography) : Teknik och tillämpning

Lundkvist, Stefan January 2013 (has links)
Before year 1895, the doctors could only make a probable diagnosis based on what the patient could tell and it was hurt and there was no discernable change to the outside of the body. With X-ray, it was possible to see inside the patient without first cutting it, you can say that the X-ray was the starting point for diagnostic imaging.The further development of X-ray gave CT (Computed Tomography), where X-ray tubes and detectors rotate around the patient while the patient table moves. Besides CT also developed MRI (Magnetic Resonance Imaging), PET (Positron Emission Tomography) and Ultrasound. Common to these methods is that the produced 3D images.In 1990 a completely new approach for diagnostic imaging, OCT (optical coherence tomography), by measuring the phase shift and the intensity of reflected light, it provides real-time and non-destructive measurements (in vivo) a resolution of 1 to 15 microns, much higher than all other standard imaging techniques. You could say that OCT machine can be compared to ultrasound, which uses the reflection of sound waves to interpretation.The first OCT machines were of type TD (Time Domain), these had low resolution and low scanning speed. In 2005 came the SD-OCT, they had higher resolution and scanning speed, SD stands for spectral domain, SD-OCT is sometimes called FD-OCT as Fourier transformed signals and operating in the frequency domain.The development of OCT machines are only in their infancy, resolution, scanning speed and accuracy will increase all the time, this allows new uses and ways to diagnose developed. OCT can be used in such Oncology, MSD (Musculoskeletal disorders), cardiovascular medicine, teeth, nerves, but the largest field is the eye and then the back of the eye called the retina (retina).This thesis is limited to the eye, the purpose is to provide input to those who are likely to purchase an OCT-machine, but also show the measurement data OCT-machines are performing and how to use the OCT-machine more than to see age-related macular degeneration. Another aim is to increase understanding of the physics behind an OCT-machine for ease of understanding the output given.The manufacture/model that have selected for evaluation are Zeiss Cirrus 4000, Topcon 3D OCT-2000 and Heidelberg Spectralis, the reason is that there are only these three on the Swedish market and all are SD-OCT. The way to evaluate OCT-machines is to scan performance and what the various analysis programs can handle. Furthermore, each OCT-machine scans the macula and optic disk on a experimental person/ reference eye, in order to get the output of the precision, or if you want to call it repeatability, which is very important if one wants to follow a solitary disease course.The conclusion of this thesis is to OCT machines are quite similar. When it comes to ease of use when doing scans is the Cirrus is lightened by the use of the extra screen where you always look eye (iris camera), which makes it easy to adjust the sharpness and position of the mouse buttons. Topcon and Heidelberg is not difficult to use but requires more experience of the person making the OCT scans. Most measurement functions in the analysis program is Topcon and Heidelberg and best accuracy/repeatability is Heidelberg, both the macula and RFNL.OCT machine is a good tool to use on the anterior segment, but in the case the precision allows the precision used to monitor RNFL thickness changes in those with glaucoma. / <p>Validerat; 20131029 (global_studentproject_submitter)</p>

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