The aim of this study were two fold. First, the study investigated whether the reading speed and reading distance changed depending on which device was used. The other part of this study evaluated whether there was any correlation between the reading distance and the participants refractive errors. This was accomplished by measuring reading speed and reading distance during reading on different devices; smartphone, tablet and an A4-paper. The participants (n=26) first went through an eye examination and additional measurements to see if they met the criteria that was required for taking part in this study. After that the participants read six texts from the Swedish version of the standardized reading test IReST on three different devices; smartphone, tablet and paper. They read two texts per device where the first round tested the reading speed and the second round tested the reading distance. Later the reading distance for the different devices were compared with the participants refractive errors. There was a statistical significant difference for the reading distance between smartphone and tablet (p=0,026) and smartphone and paper (p=0,004). However there was no statistical significant difference in reading distance between tablet and paper (p=0,60). The study showed no statistical significant difference in reading speed between the different devices (p>0,05). A completed comparison between the reading distance of the different devices and the participants refractive error showed no statistical significant correlation (r<0,80). The study showed that there was an impact in reading distance due to which device that were used. There was a statistical significant difference in reading distance between smartphone and tablet and smartphone and paper. However, there was no difference in reading speed between the different devices. The correlation between the reading distance for the different devices and the participants refractive error was not statistically significant.

While radio frequency identification tags (RFIDs) have been widely used for identifying objects (and some people), their primary use has been for access control, inventory, and other similar purposes. In this thesis we will use the detection of an RFID to indicate that a user is present in a given location.  This will be used to extend a Session Initiation Protocol (SIP) system with user presence. A typical HF RFID reader is able to read a tag from a range of 8-10 cm. In this application we wish to read tags from a range of 50 to 100 cm (the width of a doorway or narrow hallway). One of the challenges is how to increase the reading range while staying below the maximum RF power limits (for reasons of safety). Providing an RFID based presence indication can be used to automatically adjust the heating, ventilation, and air conditioning system of a room, etc. This thesis presents several different antennas which were analyzed and simulated using FEKO to obtain a suitable antenna for this target application. The thesis shows that fractal patterns are the best for the intended application based upon the results of simulations. These antennas were implemented and tested. The prototype establishes that such antennas are a suitable design and can be used with current RFID systems to achieve long ranges. The thesis also suggests some future enhancements to these antennas. / Identifiering av radiofrekvenstaggar (RFID) har använts i stor utsträckning för att identifiera objekt (och vissa människor). De primära användningsområdena har varit åtkomstkontroll, inventering, och andra liknande ändamål. I denna avhandling kommer vi att använda närvaroupptäckten av en RFID-tagg för att ange att en användare befinner sig påen given plats. Detta kommer att användas för att utöka ett Session Initiation Protocol-system med användarnärvaro. En typisk HF RFID-läsare kan läsa en tagg från ett avstånd av 8-10 cm. I denna appliceringen vill vi läsa RFID-taggar från ett avstånd av 50 till 100 cm (bredden påen dörröppning eller en smal korridor). En av utmaningarna är hur man kan öka läsavståndet och samtidigt hålla sig under de maximala RF-effektgränserna (av säkerhetsskäl). En RFIDbaserad närvaroindikering kan användas för att automatiskt justera värme, ventilation och luftkonditionering av ett rum, osv. I denna avhandling kommer vi att presentera olika antenner som analyserades och simulerades med hjälp av FEKO, för att erhålla en lämplig antenn. Avhandlingen visar att de bästa resultaten från simuleringarna för det huvudsakliga målet, är att använda fraktala mönster. Genomförandet och testerna av dessa antenner leder till en prototyp av en gynnsam antennutformning, som en bas för framtida förbättringar. Dessutom beskriver vi skälen till varför fraktalantenner ofta används i nuvarande RFID-system för att uppnålånga läsavstånd.