Sökning: "Engineering and Technology Civil Engineering Geotechnical Engineering"

Visar resultat 1 - 5 av 200 avhandlingar innehållade orden Engineering and Technology Civil Engineering Geotechnical Engineering.

  1. 1. Distributed thermal response tests : New insights on U-pipe and Coaxial heat exchangers in groundwater-filled boreholes

    Författare :José Acuña; Björn Palm; Jeffrey Spitler; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Borehole heat exchangers; Distributed Thermal Response Test; Ground Source Heat Pumps; Coaxial; U-pipe; Multi-pipe; Pipe-in-pipe; Multi-chamber; Groundwater; Thermosyphon; SRA - Energy; SRA - Energi;

    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

  3. 2. Structural Reliability and Identification with Stochastic Simulation - Application to Railway Mechanics

    Författare :Sadegh Rahrovani; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; model reduction; time-integration; finite element model; sleeper-ballast load characterization; stochastic simulation; Bayesian system identification;

    Sammanfattning : System identification of structures based on measured response data can play a key role in improving reliability based structural designs. However, the experimental limitations of in situ tests and uncertainties of required model complexity together with the inverse nature of system identification give rise to a number of challenging issues. LÄS MER

  4. 3. Secure GNSS-based Positioning and Timing : Distance-Decreasing attacks, fault detection and exclusion, and attack detection with the help of opportunistic signals

    Författare :Kewei Zhang; Panagiotis Papadimitratos; Erik G. Larsson; Christina Pöpper; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Electrical Engineering; Elektro- och systemteknik;

    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

  5. 4. Sedimentation and Its Challenge for Sustainability of  Hydraulic Structures : A Case Study of Mosul Dam Pumping Station

    Författare :Mohammad Ezz-Aldeen Mohammad; Sven Knutsson; Nadhir Al-Ansari; Jan Laue; Rafid Al Khaddar; Luleå tekniska universitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Geoteknik; Soil Mechanics;

    Sammanfattning : A successful management and operation of water resources projects are essential to maintain their functions. Dams and reservoirs are one of the largest worldwide infrastructures. They serve one or more functions; reliable store and release of water for different purposes, hydropower generation and   flood and draught controls. LÄS MER

  7. 5. GNSS hardware biases in code and carrier phase observables

    Författare :Martin Håkansson; Milan Horemuz; Anna B. O. Jensen; Lambert Wanninger; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; GNSS; GNSS positioning; hardware biases; phase biases; multi-GNSS; GPS; GLONASS; Galileo; BeiDou; satellite dependency; characterization; android; mass market; Group delay variations; nadir dependence; ionosphere modeling; ionospheric tomography; Geodesy and Geoinformatics; Geodesi och geoinformatik; Geodesi; Geodesy;

    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