Sökning: "Teknik och teknologier Samhällsbyggnadsteknik Geoteknik"
Visar resultat 1 - 5 av 189 avhandlingar innehållade orden Teknik och teknologier Samhällsbyggnadsteknik Geoteknik.
1. Distributed thermal response tests : New insights on U-pipe and Coaxial heat exchangers in groundwater-filled boreholes
Sammanfattning : U-pipe Borehole Heat Exchangers (BHE) are widely used today in ground source heating and cooling systems in spite of their less than optimal performance. This thesis provides a better understanding on the function of U-pipe BHEs and Investigates alternative methods to reduce the temperature difference between the circulating fluid and the borehole wall, including one thermosyphon and three different types of coaxial BHEs. LÄS MER
2. GNSS hardware biases in code and carrier phase observables
Sammanfattning : GNSS hardware biases appear in code and phase observations, and originates both from the receiver and satellite hardware. The presence of biases in GNSS observations might affect the accuracy in precise GNSS positioning applications, and might also be of relevance in other GNSS applications. LÄS MER
3. Secure GNSS-based Positioning and Timing : Distance-Decreasing attacks, fault detection and exclusion, and attack detection with the help of opportunistic signals
Sammanfattning : With trillions of devices connected in large scale systems in a wired or wireless manner, positioning and synchronization become vital. Global Navigation Satellite System (GNSS) is the first choice to provide global coverage for positioning and synchronization services. LÄS MER
4. Inventory of geomechanical phenomena related to train-induced vibrations from tunnels
Sammanfattning : Banverket is expecting that the number of railway tunnels in densely populated areas will increase over the next 20 years due to the lack of available space on the ground surface, but also since the railway is considered an environmentally friendly solution of transportation for the future. The need for good predictions of vibration and noise levels in dwellings along the planned tunnels is therefore evident. LÄS MER
5. Load-Haul-Dump operations in underground mines
Sammanfattning : The research presented in this thesis addresses several aspects of loading operations inunderground mines, in particular tools and equipment selection. It also addresses the flexibilityof the fleet when subject to substantial disturbances, such as ore pass loss, and proposes integration of the scheduling system with discrete event simulation. LÄS MER