Sökning: "parametric coding"

Visar resultat 1 - 5 av 7 avhandlingar innehållade orden parametric coding.

  1. 1. Towards flexible audio coding

    Författare :Renat Vafin; Bastiaan Kleijn; Juergen Herre; KTH; []
    Nyckelord :ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Electronics; Audio coding; multistage coding; waveform coding; parametric coding; sinusoidal coding; Elektronik; Electronics; Elektronik;

    Sammanfattning : thesis is about audio coding and improving flexibility thereof. Audio coding is used to reduce the bit rate needed to represent audio signals in digital format. When the available bit rate is low, parametric coding methods that use models to describe perceptually-important features of audio signals have shown their efficiency. LÄS MER

  2. 2. Towards Asymptotic Vector Quantization

    Författare :Jonas Samuelsson; Chalmers University of Technology; []
    Nyckelord :EM algorithm; parametric models; expectation maximization; spectrum coding; Gaussian mixture models; fast search; bounded support; multidimensional companding; vector quantization; high rate quantization;

    Sammanfattning : We study topics in source coding, and vector quantization (VQ) in particular. We approach VQ from two directions: a theoretical starting point based on high rate quantization theory, and a practical based on a database desription of the signal source. LÄS MER

  3. 3. Studies of genetic and environmental influences on Parkinson's disease

    Författare :Karin Wirdefeldt; Karolinska Institutet; Karolinska Institutet; []
    Nyckelord :MEDICAL AND HEALTH SCIENCES; MEDICIN OCH HÄLSOVETENSKAP; Parkinson s disease; genetic linkage; autosomal dominant; in situ hybridization; a-Synuclein; twin; heritability; co-twin control; smoking;

    Sammanfattning : Parkinson's disease (PD) is the second most common neurodegenerative disorder after Alzheimer's disease. Little is known about the etiology of PD. Although several PD genes are known, these are thought to be involved in only a small proportion of all PD cases. LÄS MER

  4. 4. Genetic studies of colorectal cancer

    Författare :Johanna Skoglund; Karolinska Institutet; Karolinska Institutet; []
    Nyckelord :MEDICAL AND HEALTH SCIENCES; MEDICIN OCH HÄLSOVETENSKAP; colorectal cancer; linkage analysis; TGFBR1; case-control study; meta-analysis;

    Sammanfattning : Colorectal cancer is the third most commonly diagnosed cancer worldwide with an incidence rate of over 1 million cases per year. A genetic contribution has been suggested to be involved in around 35% of all colorectal cancer cases. LÄS MER

  5. 5. Estimation and Performance Analysis of Wireless Multiple Antenna Communication Channels

    Författare :Mikael Coldrey; Chalmers University of Technology; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; MIMO; generalized beamforming; Wireless communications; training; channel estimation; distributed sources; capacity; performance bounds;

    Sammanfattning : The focus of this thesis is on channel estimation in wireless communication systems that employ multiple antennas.The thesis is divided into two parts, whereof the first part addresses theproblem of parameter estimation of distributed sources. Due to, e.g. LÄS MER