Sökning: "Roland Eriksson"
Visar resultat 1 - 5 av 18 avhandlingar innehållade orden Roland Eriksson.
1. On the Ising problem and some matrix operations
Sammanfattning : The first part of the dissertation concerns the Ising problem proposed to Ernst Ising by his supervisor Wilhelm Lenz in the early 20s. The Ising model, or perhaps more correctly the Lenz-Ising model, tries to capture the behaviour of phase transitions, i.e. how local rules of engagement can produce large scale behaviour. LÄS MER
2. On Latin squares and avoidable arrays
Sammanfattning : This thesis consists of the four papers listed below and a survey of the research area. I Lina J. Andrén: Avoiding (m, m, m)-arrays of order n = 2k II Lina J. Andrén: Avoidability of random arrays III Lina J. LÄS MER
3. Development of on-line diagnostic methods for medium voltage XLPE power cables
Sammanfattning : On-line diagnostics of power system components is an important area since it allows the diagnostics to be performed at regular intervals during the normal operation of the components. This combined with reliability centered maintenance could lead to reduced customer outages. LÄS MER
4. On-line time domain reflectometry diagnostics of medium voltage XLPE power cables
Sammanfattning : Degradation of XLPE insulated power cables by water-trees is a primary cause of failure of these cables. The detection of water-trees and information about the severity of the degradation can be obtained with off-line measurement using dielectric spectroscopy. In many situations only a limited part of the cable may be degraded by the water-trees. LÄS MER
5. Modelling of cavity partial discharges at variable applied frequency
Sammanfattning : The presence of partial discharges (PD) in high voltage components is generally a sign of defects and degradation in the electrical insulation. To diagnose the condition of high voltage insulation, PD measurements is commonly used. LÄS MER
