E911 creep samples exposed to temperatures of 600˚C, 625˚C and 650˚C at differing stress levels were supplied by CORUS. The hardness of the gauge length that experienced both creep strain and temperature was found to be lower than that of the head where thermal softening only can be assumed. The changes in the morphology and size of precipitates were observed qualitatively by optical microscopy and Scanning Electron Microscopy. A creep fracture mechanism map of E911 steel was constructed with two modes of creep (transgranular and intergranular ). A fitted ellipse shape was used to characterise the irregular block shape by Electron Backscattered Diffraction (EBSD). It showed that the width of the block inside a prior austenite grain increases more rapidly in the gauge length than in the head; subgrain growth was also observed by EBSD. Transmission Electron Microscopy studies indicate that at 600°C E911 steel can reach up to 75647 hours creep rupture life (108MPa), which is due to the relatively small size of M23C6, Laves and M2X phases. However, Z phase precipitation results in a drop in creep resistance owing to the dissolution of fine MX phase and the transformation of M2X phase. At 625°C and 650°C, the creep rupture life decreases owing to the coarsening of Laves, M23C6 and M2X phases. Four experimental steel casts were prepared with varying levels of Ni and Cr to investigate the effect of these elements on Z phase formation. After 10,000 hours exposure, there was little evidence of Z phase in the samples studied and therefore it is difficult to draw definitive conclusions about the role of Ni or Cr in promoting Z phase formation. It is possible that the casts studied here will allow better conclusions to be drawn after exposing the samples to longer durations.

Global Navigation Satellite Systems (GNSS) have found wide adoption in various applications, be they military, civilian or commercial. The susceptibility of GNSS to radio-frequency interference can, thus, be very disruptive, even for emergency services, therefore threatening people's lives. An early prototype of a system providing relatively cheap widescale GNSS jamming detection, called J911, is explored in this thesis. J911 is smartphone-based crowdsourcing of GNSS observations, most interesting of which are carrier-to-noise-density ratio (<img src="http://www.diva-portal.org/cgi-bin/mimetex.cgi?%5Cfrac%7BC%7D%7BN_0%7D" />) and Automatic Gain Control (AGC) voltage. To implement the prototype, an Android application to provide the measurements, a backend to parse and store the measurements, and a frontend to visualize the measurements were developed. In real-world use, the thesis argues, the J911 system would best be implemented over existing Enhanced 9-1-1 (E911) infrastructure, becoming a standardized part of the Public Switched Telephone Network (PSTN). The Android application, running on a smartphone, would periodically construct messages to be sent to the backend over an Internet connection. The messages would include: current location from all location providers available in Android OS, observed satellites from all supported constellations, the satellites' <img src="http://www.diva-portal.org/cgi-bin/mimetex.cgi?%5Cfrac%7BC%7D%7BN_0%7D" />, and a timestamp. Once a message is received on the backend, the data would be extracted and stored in a database. The frontend would query the database and produce a map with the collected datapoints overlaid on top of it, whose color indicates received signal strength at that point. When a jammer gets close enough to a few smartphones, they will all be jammed, which is easily observed on the map. On top of that, if enough samples are gathered, a Power Difference of Arrival localization algorithm can be used to localize the jammer. The smartphones that the system was planned to be tested with did not support AGC level readings, therefore in order to obtain AGC levels over time, a few SiGe GN3S Samplers, which are radio-frequency frontends, were used. In eastern Idaho, United States, over three nights in July 2017, an exercise, named 2017 DHS JamX, was performed with the help of the US Department of Homeland Security. Sadly, the approval for the publication of the test results did not come in time to be included in this thesis.

The aim of the work is the radio access network of mobile networks second, third and fourth generation. The main objective is a description of the radio access network of the second, third and fourth generation, their elements, interfaces and signaling procedures. The next part describes the emergency services and the architecture of the fourth generation mobile networks. The practical part is then devoted to identify actions needed to prepare radio access network to testing emergency services, identify actions needed to conversion of transport protocol fixed part of the radio access network from IPv4 to IPv6 and describe the intervention to radio access network to change the active segment of the core network.

Detta arbete behandlar mobilpositionering och relaterade tjänster, så kallade location-based services. Syftet med arbetet är att undersöka hur mobilpositionering kommer att utvecklas i takt med att nya mobilsystem tillåter mer avancerade mobila tjänster. En applikation, Finder Client har utvecklats för att kunna visa vänners positioner på en handdators karta. Kartorna som används finns i färdiga ruttplaneringsprodukter som installeras på handdatorn. Positioneringen sker via en GSM-telefon och SMS. Syftet är även att visa att man kan spara data på handdatorn för att göra intelligentare applikationer. Utvecklingen har gjorts i OPL för en Psion 5mx handdator. OPL är inbyggt i Psion och liknar språk som Pascal och Basic. Slutsatsen är att det går bra att utveckla en Finder klient för handdatorer men det vore mer användarvänligt att utveckla den för en kombinerad handator och mobiltelefon, en så kallad Smart Phone. Man kan också tänka sig att GSM-positionering blir en del av ett ruttplaneringsprogram precis som GPS-positionering är idag. En marknadsundersökning har utförts i examensarbetet. Det kan konstateras att en kombination av GSM- och GPS-positionering kommer troligen att vara lyckosammast i framtiden. De drivande krafterna inom mobilpositionering är den amerikanska statens påbud att alla mobiltelefoner ska kunna positioneras vid alarmsamtal (E911) samt att mobiltelefonoperatörerna ser tjänsterna som en ny potentiell inkomstkälla. Det är mycket svårt att säga vilka tjänster som kommer att bli populära i framtiden. Lösningar som riktar sig till ungdomar, underhållningsbranchen och mot att navigera/spåra fordon ser dock mycket intressanta ut. Det är troligt att positionering kommer att utgöra en liten del i många framtida mobila tjänster. ABSTRACT This work deals with the aspects of location-based services. The aim is to investigate how mobile positioning is going to develop in relation to the fact that new mobile system allows more advanced mobile services. An application, an enhanced Finder Client is developed. It uses maps to display friends’ positions on a handheld computer (PDA). The maps are off-the-shelf route planning products that are installed on the PDA. The positioning is made using a GSM mobile phone and SMS as a means for communication. The aim is also to show that it is possible to store large amounts of data on the PDA to make more intelligent applications. The development is performed in OPL on a Psion 5mx handheld computer. OPL is Psion’s built-in programming language, quite similar to languages like Pascal and Basic. The conclusion is that it is possible to develop a Finder Client for handheld computers but it would be more user-friendly to develop the client on a combined mobile phone and a PDA: a Smart Phone. It can also be possible to incorporate GSM positioning into the map software just as GPS positioning is a part of them today. A market overview has also been performed. The conclusion is that a combination of GSM and GPS positioning is probably the most successful solution for the future. The driving force is the Federal Communications Commissions, FCCs E911 decree, which regulates that all emergency calls from a mobile phone must be able to be positioned. Another aspect is that the mobile operators consider location-based services to be a new source for income. It is difficult to estimate which solutions that are going to be popular in the future. Services focusing on the youth, entertainment and vehicle navigation/tracking seems however to be the most interesting. It is likely to believe that mobile positioning is going to be a small part in many mobile services in the future. / Validerat; 20101217 (root)

As the demand for wireless communication systems has exploded over the past few years, many researchers have taken on the challenge to model wireless channels more accurately. These models are very useful for enhancing the design of all aspects of wireless communications. Smart antennas and systems used in position location are among the most popular new studies that require signal information such as the amplitude, phase, and angle-of-arrival (AOA) of multipath delay spreads. For proper and efficient implementation of future systems, emerging wireless systems must be able to exploit processing of spatial information. The goal of the work presented in this thesis is to further improve two channel modeling tools, SMRCIM and SIRCIM, by implementing new geometrical models that provide users with angle-of-arrival information as well as amplitude and phase data for wideband wireless communication channels. The new angle-of-arrival models are explained and pseudo code is provided to demonstrate the software implementation of the models. Likewise, the channel models are explained and the usage and results of the simulation tools are described. The SMRCIM and SIRCIM tools are currently being used by researchers throughout the world. <i>[Vita removed March 5, 2012. Gmc]</i> / Master of Science