Sökning: "variational regularization"

Visar resultat 1 - 5 av 6 avhandlingar innehållade orden variational regularization.

  1. 1. Ghosts and machines : regularized variational methods for interactive simulations of multibodies with dry frictional contacts

    Författare :Claude Lacoursière; Bo Kåggström; Ander Klarbring; Umeå universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Discrete mechanics; Variational method; Contact problems; Impacts; Least action principle; Saddle point problems; Lagrange Multipliers; Constrained systems; Multibody Systems; Numerical regularization; Constraint realization; Constraint stabilization; Dry friction; Differential Algebraic Equations; Nonsmooth problems; Linear Complementarity; Quaternion algebra; Numerical linear algebra; Physics modeling; Interactive simulation; Numerical stability; Rigid body dynamics; Dissipative systems; Computational physics; Beräkningsfysik;

    Sammanfattning : A time-discrete formulation of the variational principle of mechanics is used to provide a consistent theoretical framework for the construction and analysis of low order integration methods. These are applied to mechanical systems subject to mixed constraints and dry frictional contacts and impacts---machines. LÄS MER

  3. 2. Multidimensional inverse problems in imaging and identification using low-complexity models, optimal mass transport, and machine learning

    Författare :Axel Ringh; Johan Karlsson; Rodolphe Sepulchre; KTH; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Inverse problems; convex optimization; variational regularization; trigonometric moment problems; optimal mass transport; computed tomography; machine learning; analytic interpolation; delay systems; Inversa problem; konvex optimering; variationell regularisering; trigonometriska momentproblem; optimal masstransport; datortomografi; maskininlärning; analytisk interpolation; system med tidsfördröjning; Mathematics; Matematik;

    Sammanfattning : This thesis, which mainly consists of six appended papers, primarily considers a number of inverse problems in imaging and system identification.In particular, the first two papers generalize results for the rational covariance extension problem from one to higher dimensions. LÄS MER

  4. 3. Variational Tensor-Based Models for Image Diffusion in Non-Linear Domains

    Författare :Freddie Åström; Michael Felsberg; George Baravdish; Reiner Lenz; Christoph Schnörr; Linköpings universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; image diffusion; variational formulation; denoising; tensor; non-linear;

    Sammanfattning : This dissertation addresses the problem of adaptive image filtering.Although the topic has a long history in the image processing community, researchers continuously present novel methods to obtain ever better image restoration results. LÄS MER

  5. 4. Sequential Data Learning, Scalable Models and Adversarial Regularization

    Författare :Jin Huang; Ming Xiao; Geyong Min; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY;

    Sammanfattning : Time Series Prediction (TSP) has been used in mobile network traffic data analysis to produce predictive results for network planning and resource allocation. In the first part of this thesis, we propose a novel method of predicting mobile network traffic using neural networks based on conditional probability modeling between adjacent data windows in the time series sequence. LÄS MER

  7. 5. Statistical Segmentation and Registration of Medical Ultrasound Data

    Författare :Mattias Hansson; Matematik LTH; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Registration; Segmentation; Feature descriptor; Statistical image and signal processing; Medical ultrasound; Variational methods; Mixture model; Bayesian; Markov Chain Monte Carlo; Similarity measur;

    Sammanfattning : The interpretation of ultrasonic imagery is typically not straightforward and of quite subjective nature and therefore strongly dependent on the expertise of its users. Thus the development of algorithms which aid in the interpretation of ultrasonic data is a highly relevant topic. LÄS MER