Search for dissertations about: "non-stationarity"

Showing result 6 - 10 of 12 swedish dissertations containing the word non-stationarity.

  2. 6. Towards Robust and Adaptive Machine Learning : A Fresh Perspective on Evaluation and Adaptation Methodologies in Non-Stationary Environments

    Author : Firas Bayram; Bestoun S. Ahmed; Patrick Glauner; Karlstads universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; machine learning; concept drift; covariate shift; performance robustness; evaluation methodology; adaptive learning; Computer Science; Datavetenskap;

    Abstract : Machine learning (ML) has become ubiquitous in various disciplines and applications, serving as a powerful tool for developing predictive models to analyze diverse variables of interest. With the advent of the digital era, the proliferation of data has presented numerous opportunities for growth and expansion across various domains. READ MORE

  4. 7. Stochastic Modeling and Management of an Emergency Call Center : A Case Study at the Swedish Emergency CallCenter Provider, SOS Alarm Sverige AB

    Author : Klas Gustavsson; Leif Olsson; Panagiotis Papapetrou; Mittuniversitetet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Call Center Management; Burst Modeling; Stochastic Resources; Skills-Based Routing; Discrete-Event-Simulation;

    Abstract : A key task of managing an inbound call center is in estimating its performance and consequently plan its capacity, which can be considered a complex task since several system variables are stochastic. These issues are highly crucial for certain time-sensitive services, such as emergency call services. READ MORE

  5. 8. Ion dynamics and structure of collisionless shocks in space

    Author : Andreas Johlander; Andris Vaivads; Robert F. Wimmer-Schweingruber; Uppsala universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Fysik med inriktning mot rymd- och plasmafysik; Physics with specialization in Space and Plasma Physics;

    Abstract : Shock waves form when supersonic flows encounter an obstacle. Like in regular gases, shock waves can form in a plasma - a gas of electrically charged particles. Shock waves in plasmas where collisions between particles are very rare are referred to as collisionless shock waves. READ MORE

  6. 9. The effect of scale on the morphology, mechanics and transmissivity of single rock fractures

    Author : Nader Fardin; KTH; []
    Keywords : Anisotropy; Aperture; Asperity degradation; Contact area; Finite Element Method FEM ; Flow analysis; Fractals; Fracture morphology; Heterogeneity; Stress-deformation; Surface roughness; Roughness-Length method; Scale dependency; Stationarity; Transm;

    Abstract : This thesis investigates the effect of scale on themorphology, mechanics and transmissivity of single rockfractures using both laboratory and in-situ experiments, aswell as numerical simulations. Using a laboratory 3D laserscanner, the surface topography of a large silicon-rubberfracture replica of size 1m x 1m, as well as the topography ofboth surfaces of several high-strength concrete fracturereplicas varying in size from 50mmx50mm to 200mm x 200mm, werescanned. READ MORE

  7. 10. Time Varying Parameters in Exchange Rate Models

    Author : Richard Henricsson; Nationalekonomiska institutionen; []
    Keywords : SAMHÄLLSVETENSKAP; SOCIAL SCIENCES; economic systems; economic theory; econometrics; Economics; stochastich volatility.; purchasing power parity; GARCH; exchange rates; Stationarity; economic policy; Nationalekonomi; ekonometri; ekonomisk teori; ekonomiska system; ekonomisk politik;

    Abstract : This thesis consists of five papers on different aspects of parametervariation in some common exchange rate models.The first paper investigates the stability in the real exchange rate, witch is equivalent to purchasing power parity (PPP). READ MORE