Sökning: "sparse"

Visar resultat 16 - 20 av 507 avhandlingar innehållade ordet sparse.

  1. 16. Urban Travel Time Estimation from Sparse GPS Data : An Efficient and Scalable Approach

    Författare :Mahmood Rahmani; Harilaos Koutsopoulos; Nikolas Geroliminis; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; map-matching; path inference; sparse GPS probes; floating car data; arterial; urban area; digital road network; iterative travel time estimation; fixed point problem; Stockholm; taxi; Transportvetenskap; Transport Science;

    Sammanfattning : The use of GPS probes in traffic management is growing rapidly as the required data collection infrastructure is increasingly in place, with significant number of mobile sensors moving around covering expansive areas of the road network. Many travelers carry with them at least one device with a built-in GPS receiver. LÄS MER

  3. 17. Group-Sparse Regression : With Applications in Spectral Analysis and Audio Signal Processing

    Författare :Ted Kronvall; Statistical Signal Processing Group; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; sparse regression; group-sparsity; statistical modeling; regularization; hyperparameter-selection; spectral analysis; audio signal processing; classification; localization; multi-pitch estimation; chroma; convex optimization; ADMM; cyclic coordinate descent; proximal gradient;

    Sammanfattning : This doctorate thesis focuses on sparse regression, a statistical modeling tool for selecting valuable predictors in underdetermined linear models. By imposing different constraints on the structure of the variable vector in the regression problem, one obtains estimates which have sparse supports, i.e. LÄS MER

  4. 18. Path Inference of Sparse GPS Probes for Urban Networks : Methods and Applications

    Författare :Mahmood Rahmani; Harilaos Koutsopoulos; Clas Rydergren; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; map-matching; path inference; sparse GPS probes; FCD; urban area; digital road network; Stockholm; taxi; iMobility Lab; MapViz; travel time; SRA - Transport; SRA - Transport;

    Sammanfattning : The application of GPS probes in traffic management is growing rapidly as the required data collection infrastructure is increasingly in place in urban areas with significant number of mobile sensors moving around covering expansive areas of the road network. Most travelers carry with them at least one device with a built-in GPS receiver. LÄS MER

  5. 19. Sparse Representations for Medium Level Vision

    Författare :Per-Erik Forssén; Gösta Granlund; Linköpings universitet; []
    Nyckelord :TECHNOLOGY; TEKNIKVETENSKAP;

    Sammanfattning : In this thesis a new type of representation for medium level vision operations is explored. We focus on representations that are sparse and monopolar. The word sparse signifies that information in the feature sets used is not necessarily present at all points. On the contrary, most features will be inactive. LÄS MER

  7. 20. Topics in Sparse Least Squares Problems

    Författare :Mikael Adlers; Michael A. Saunders; Linköpings universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES;

    Sammanfattning : This thesis addresses topics in sparse least squares computation. A stable method for solving the least squares problem, min ||Ax-b||2 is based on the QR factorization.Here we have addressed the difficulty for storing the orthogonal matrix Q. LÄS MER