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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.
31

Zpracování obrazu prostřednictvím mobilních zařízení

Čermák, Pavel January 2013 (has links)
No description available.
32

A comparison between vector algorithm and CRSS algorithm for indoor localization

Dama, Yousef A.S., Abd-Alhameed, Raed, Hammad, H., Zaid, R., Excell, Peter S. January 2014 (has links)
yes / In this paper a comparison between two indoor localization algorithms using received signal strength is utilized the vector algorithm and the Comparative Received Signal Strength algorithm. The comparison considered the effect of the radio map resolution, the number of access points, and the operating frequency on the accuracy of the localization process. The experiments were carried out using ray tracing software, measured values and MATLAB.
33

A Low-Infrastructure Approach to Indoor Localization and Tracking using Lighting Information

Edwards, Eric 01 1900 (has links)
Low-infrastructure techniques for indoor localization attempt to provide indoor positioning information for users, without requiring the installation of specialized transmitting or receiving hardware. Such an approach should encourage further adoption of indoor positioning systems by reducing the installation burden on individual building owners. If fully adopted, indoor positioning could prove to be a valuable addition to the existing outdoor localization system based on GPS. In this work, a particle filter is used to combine motion and light data in order to provide positioning information for a user in an indoor environment. A simple lighting model is used to predict light measurements, while an orientation tracking algorithm provides information about user motion. The system is shown to work with the existing lighting infrastructure of a building, though the addition of visible light communication (VLC) enabled light fixtures is shown to further improve performance. An experimental demonstration of the proposed system is provided, which indicates that tracking accuracy on the order of ten’s of centimetres is possible with very low infrastructure requirements. / Thesis / Master of Applied Science (MASc)
34

Point cloud scan selection for indoor floor plan generation

Frincu, Cristian January 2019 (has links)
Building Information Models (BIM) are becoming a standard in the construction indus- try for storing information about buildings and assets. Automatically creating BIMs has attracted a lot of attention, as it has great potential to improve efficient resource man- agement. A detailed description of the building can decrease the cost of management, heating and cooling, and restoration. For pre-existing structures design documents are typically outdated or unavailable, making BIMs challenging to acquire. The field of indoor floor plan creation has grown in recent years due to advancements in LIDAR technology. However, LIDARs create millions of points per scan, making it computationally expensive to process all of them. In order to properly create a floor it is imperative to acquire a sufficient number of scans to visualize the whole building, while simultaneously minimizing the number of scans for computational reasons. We propose a method for selecting a subset of the scans, as well as a method for clustering points into lines to be used for floor plan extraction. Our method works by clustering nearby points, creating a convex hull around them, and selecting scans based on the most area covered by the union of the hulls. The point clustering splits the pointcloud into potential lines by projecting each point along its surface normal, clustering points from the same line together. Those improvements allow for the efficient generation of floor plans for large buildings. / Thesis / Master of Science (MSc)
35

Impact of Positioning Technology on Human Navigation

2015 May 1900 (has links)
In navigation from one place to another, spatial knowledge helps us establish a destination and route while travelling. Therefore, sufficient spatial knowledge is a vital element in successful navigation. To build adequate spatial knowledge, various forms of spatial tools have been introduced to deliver spatial information without direct experience (maps, descriptions, pictures, etc.). An innovation developed in the 1970s and available on many handheld platforms from the early 2000s is the Global Position System (GPS) and related map and text-based navigation support systems. Contemporary technical achievements, such as GPS, have made navigation more effective, efficient, and comfortable in most outdoor environments. Because GPS delivers such accurate information, human navigation can be supported without specific spatial knowledge. Unfortunately, there is no universal and accurate navigation system for indoor environments. Since smartphones have become increasingly popular, we can more frequently and easily access various positioning services that appear to work both indoors and outdoors. The expansion of positioning services and related navigation technology have changed the nature of navigation. For example, routes to destination are progressively determined by a “system,” not the individual. Unfortunately we only have a partial and nascent notion of how such an intervention affects spatial behaviour. The practical purpose of this research is to develop a trustworthy positioning system that functions in indoor environments and identify those aspects those should be considered before deploying Indoor Positioning System (IPS), all towards the goal of maintaining affordable positioning accuracy, quality, and consistency. In the same way that GPS provides worry free directions and navigation support, an IPS would extend such opportunities to many of our built environments. Unfortunately, just as we know little about how GPS, or any real time navigation system, affects human navigation, there is little evidence suggesting how such a system (indoors or outdoors) changes how we find our way. For this reason, in addition to specifying an indoor position system, this research examines the difference in human’s spatial behaviour based on the availability of a navigation system and evaluates the impact of varying the levels of availability of such tools (not available, partially available, or full availability). This research relies on outdoor GPS, but when such systems are available indoors and meet the accuracy and reliability or GPS, the results will be generalizable to such situations.
36

Inomhus- och arbetsmiljön i grund- och gymnasieskolan : En studie i Malå och Norsjö kommuner / Indoor environment in schools : a study in the municipality of Malå and Norsjö (Sweden)

Ohlsson, Ida January 2014 (has links)
The purpose of this study was to examine the school environment in the municipalities of Malå and Norsjö. The study focused on cleaning, ventilation, classroom noise and illumination which are the most important factors for a good indoor climate and a good working environment in school. The study was performed by inspection of school buildings, questionnaire among school children and measurements of CO2. The result showed that all the visited schools did not meet the Swedish standards for cleaning and ventilation, also sound environment and the illumination had inadequacies in some of the classes. The result also showed that the majority of the pupils were satisfied with the indoor climate and working environment. Of the total percentage of pupils surveyed, 35% of the pupils were unsatisfied with the cleanliness of the toilets and 44% reported that the sound level is perceived as disturbing. The measurements of CO2 showed that all schools had concentrations (ranging from 541-926 ppm) below the Swedish standard (1 000 ppm), nevertheless there was indications that these concentrations may increase during a day. In conclusion this study showed that the indoor environment in the visited schools had inadequacies which may have a negative impact of the pupils. To avoid unhealthy, and from a public health perspective, these inadequacies should be attended.
37

Reference values for building material emissions and indoor air quality in residential buildings /

Järnström, Helena. January 1900 (has links) (PDF)
Thesis (doctoral)--University of Kuopio, 2008. / Includes bibliographical references. Also available on the World Wide Web.
38

[en] INDOOR PROPAGATION STUDIES FOR WLAN PLANNING / [pt] ESTUDO DE PROPAGAÇÃO EM AMBIENTES FECHADOS PARA O PLANEJAMENTO DE WLANS

MARCELO NAJNUDEL 21 June 2004 (has links)
[pt] Recentemente, tem sido observado um crescimento explosivo na utilização de redes de acesso local sem fio (Wireless Local Area Networks - WLANs), utilizando equipamentos de nível de radiação restrito operando em bandas independentes de outorga de uso de rádio freqüência, tanto para uso corporativo como doméstico e para prover acesso pago em ambientes públicos como aeroportos, hotéis, centros de convenções, campi universitários e mesmo restaurantes e cafés. Se estas redes serão complementares ou competidoras das redes celulares de terceira e quarta gerações é ainda uma questão polêmica e aberta. Os objetivos deste trabalho são o desenvolvimento um modelo de propagação de sinais na faixa de freqüência de 2,4 GHz em ambientes fechados (indoor), para a previsão de cobertura de WLANs, e prover ao projetista de redes wireless uma metodologia um bom dimensionamento da rede. São apresentados os principais modelos semi-empíricos já existentes na literatura técnica e, a partir de medidas realizadas em diferentes ambientes, é proposto um ajuste de parâmetros de um modelo de propagação indoor bastante completo. As medidas realizadas incluem as perdas de penetração em paredes de diferentes materiais, o efeito de difração em quinas de paredes, efeito de movimentação de pessoas no ambiente, além do coeficiente de perda de propagação com a distância. Os modelos desenvolvidos foram implementados numa ferramenta de software para o planejamento de cobertura de redes wireless indoor que permite realizar o projeto a partir da planta baixa do ambiente disponibilizada em arquivos de imagem. / [en] Recently, an explosive growth in the use of Wireless Local Area Networks - WLANs, using restricted radiation levels and operating in license exempted frequency bands, has been observed, not only for corporative domestic use but also to provide paid internet access in public environments such as airports, hotels, convention centers, university campus and even restaurants and coffee shops. The question if these networks will be complementary or will compete with third and forth generation of cellular networks, is still a controversial and opened. The objectives of this work are the development a model for propagation in closed environments (indoor) at the 2,4 GHz frequency band for the coverage planning of WLANs and to provide the wireless network designer with a complete project methodology . The most important semi-empirical models available in the technical literature are presented and, based on measurements carried out in different environments, a fairly complete model with fitted parameters is proposed. The measurements include losses of penetration in walls of different materials, the effect of diffraction at wall edges, the effect of movement of people in the environment and the rate of loss with distance coefficient. The developed models have been implemented in a software tool for coverage planning of wireless indoor networks that allows the development of the project starting from blue prints of the environment available as digital image files.
39

Indoor localization using received signal strength

Obeidat, Huthaifa A.N., Abd-Alhameed, Raed, Noras, James M., Zhu, Shaozhen (Sharon), Ghazaany, Tahereh S., Ali, N.T., Elkhazmi, Elmahdi A. January 2013 (has links)
No / A comparison between two indoor localization algorithms using received signal strength is carried out. The first algorithm is the vector algorithm; the second is the matrix algorithm. The comparison considered the effects of the reference points, the access point, and the frequency on the accuracy of the localization process. The experiments were carried out using ray tracing software and MATLAB. This paper justifies the use of adopting the matrix algorithm.
40

An Indoor Localization System Based on BLE Mesh Network

Silver, Oscar January 2016 (has links)
Internet of Things (iot) is a growing field enabled by many different technologies. One of these technologies is  Bluetooth Low Energy (ble). It is of interest to investigate the potential of ble and one interesting, currently unsupported, feature is mesh networking. This thesis work aims to investigate whether it is possible to design and implement a mesh network protocol using ble. To verify the implemented mesh network protocols functionality an indoor localization system has been implemented upon the BLE mesh network protocol. Furthermore this thesis work investigates if an indoor localization system can benefit from using a mesh network. The results of the investigation is a proof of concept of a functional ble mesh network protocol implemented on hardware and tested in a real environment. Tests show that the implemented localization system has similar accuracy as other rssi based indoor localization systems. The largest advantage found for a mesh based indoor localization is the ability to localize objects outside of the radio propagation range of the user. This feature is enabled by multi-hop messaging in the mesh network.

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