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Visar resultat 1 - 5 av 83 avhandlingar som matchar ovanstående sökkriterier.

  1. 1. Estimation and detection of transmission line characteristics in the copper access network

    Författare :Fredrik Lindqvist; [2011]
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Digital subscriber line; DSL; line qualification; twisted-pair line; copper access network; cable modeling; crosstalk channel estimation; estimation; detection;

    Sammanfattning : The copper access-network operators face the challenge of developing and maintaining cost-effective digital subscriber line (DSL) services that are competitive to other broadband access technologies. The way forward is dictated by the demand of ever increasing data rates on the twisted-pair copper lines. LÄS MER

  2. 2. Impact Evaluation of Intentional Electromagnetic Interference (IEMI) on Targeted Loads in Complex Networks Using Analytical Investigations

    Detta är en avhandling från KTH Royal Institute of Technology

    Författare :Bing Li; Daniel Månsson; Nelson Theethayi; [2017]
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Intentional Electromagnetic Interference; Networks; BLT; Transmission Line; Electrical Engineering; Elektro- och systemteknik;

    Sammanfattning : With the proliferation of various electronic and electrical devices, IEMI has become a critical issue that may severely threaten the modern society. For practical protection considerations, it is crucial to comprehensively evaluate the potential damages resulted by IEMI. LÄS MER

  3. 3. Harmonic Mitigation in Traction Drives

    Detta är en avhandling från Department of Industrial Electrical Engineering and Automation, Lund Institute of Technology

    Författare :Hans Bängtsson; [1999]
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; hydraulics; Mechanical engineering; converter; line interference; track circuit; Railway signalling system; vacuum technology; vibration and acoustic engineering; Maskinteknik; hydraulik; vakuumteknik; vibrationer; akustik;

    Sammanfattning : In railway traffic the low friction between wheel and rail causes long braking distances, normally much longer than the sight distance of the driver, i.e. if the driver starts the braking when a problem on the track is discovered, it might be too late to brake the train. Therefore, safe railway traffic can not only rely on the driver. LÄS MER

  4. 4. Electromagnetic Interference in Distributed Outdoor Electrical Systems, with an Emphasis on Lightning Interaction with Electrified Railway Network

    Detta är en avhandling från Uppsala : Institutionen för teknikvetenskaper

    Författare :Nelson Theethayi; Uppsala universitet.; [2005]
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Electrical engineering; Electromagnetic Compatibility EMC ; Lightning; Lightning Protection; Transmission Lines; Electromagnetic Wave Propagation; Underground Cables; Grounding; Electromagnetic Transients; Electromagnetic Interference; Shielding Effectiveness; Railway Systems; Elektroteknik; elektronik och fotonik; TECHNOLOGY Electrical engineering; electronics and photonics; TEKNIKVETENSKAP Elektroteknik; elektronik och fotonik;

    Sammanfattning : This thesis deals with the electromagnetic compatibility (EMC) problems of distributed electrical networks, especially that caused by lightning to electrified railway. Lightning transients were found to damage important devices that control train movements, causing traffic stoppage and delays. LÄS MER

  5. 5. Interference competition between arctic and red foxes

    Detta är en avhandling från Stockholm : Department of Zoology, Stockholm University

    Författare :Bodil Elmhagen; Devra G Kleiman; [2003]
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURAL SCIENCES Biology Terrestrial; freshwater and marine ecology Terrestrial ecology; NATURVETENSKAP Biologi Terrestisk; limnisk och marin ekologi Terrestisk ekologi;

    Sammanfattning : In this thesis, I investigate the relationship between arctic foxes Alopex lagopus and red foxes Vulpes vulpes in Swedish mountain tundra habitat (fjällen). The arctic fox population was severely reduced by hunting in the early 20th century. LÄS MER