Sökning: "bounds"

Visar resultat 1 - 5 av 489 avhandlingar innehållade ordet bounds.

  1. 1. Low-angle estimation : Models, methods and bounds

    Författare :Katarina Boman; Peter Stoica; Uppsala universitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Signal Processing; Signalbehandling;

    Sammanfattning : In this work we study the performance of elevation estimators and lower bounds on the estimation error variance for a low angle target in a smooth sea scenario using an array antenna. The article is structured around some key assumptions on multipath knowledge, signal parameterization and noise covariance, giving the reader a framework in which Maximum Likelihood estimators exploiting different á priori information can be found. LÄS MER

  3. 2. Bounds on Hilbert Functions

    Författare :Ornella Greco; Mats Boij; Aldo Conca; KTH; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Hilbert Functions; Commutative Algebra;

    Sammanfattning : This thesis is constituted of two articles, both related to Hilbert functions and h-vectors. In the first paper, we deal with h-vectorsof reduced zero-dimensional schemes in the projective plane, and, in particular, with the problem of finding the possible h-vectors for the union of two sets of points of given h-vectors. LÄS MER

  4. 3. Lower Bounds and Trade-offs in Proof Complexity

    Författare :Susanna F. de Rezende; Jakob Nordström; Amit Chakrabarti; KTH; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Proof complexity; trade-offs; lower bounds; size; length; space; Computer Science; Datalogi;

    Sammanfattning : Propositional proof complexity is a field in theoretical computer science that analyses the resources needed to prove statements. In this thesis, we are concerned about the length of proofs and trade-offs between different resources, such as length and space. LÄS MER

  5. 4. Optimization and Physical Bounds for Passive and Non-passive Systems

    Författare :Yevhen Ivanenko; Sven Nordebo; Börje Nilsson; Mats Gustafsson; Mariana Dalarsson; Aaron Welters; Linnéuniversitetet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Convex optimization; physical bounds; Herglotz functions; quasi-Herglotz functions; passive systems; non-passive systems; approximation; absorption in lossy media; Waves; Signals and Systems; Vågor; signaler och system;

    Sammanfattning : Physical bounds in electromagnetic field theory have been of interest for more than a decade. Considering electromagnetic structures from the system theory perspective, as systems satisfying linearity, time-invariance, causality and passivity, it is possible to characterize their transfer functions via Herglotz functions. LÄS MER

  7. 5. Fundamental Bounds on Performance of Periodic Electromagnetic Radiators and Scatterers

    Författare :Andrei Ludvig-Osipov; B. Lars G. Jonsson; Christophe Caloz; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Q-factor; bandwidth; antenna arrays; periodic structures; physical bounds; physical limitations; Electrical Engineering; Elektro- och systemteknik;

    Sammanfattning : In this thesis, the optimal bandwidth performance of periodic electromagnetic radiators and scatterers is studied. The main focus is on the development and application of methods to obtain fundamental physical bounds, relating geometrical parameters, frequency bandwidth, efficiency and radiation characteristics of periodic electromagnetic structures. LÄS MER