Sökning: "Cholesky decomposition"

Hittade 5 avhandlingar innehållade orden Cholesky decomposition.

  1. 1. New Approaches to Large-Scale Electronic Structure Calculations

    Författare :Francesco Aquilante; Teoretisk kemi; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Theoretical chemistry; orbital localization; electron correlation; analytic gradients; Cholesky decomposition; density fitting; quantum chemistry; Teoretisk kemi; kvantkemi;

    Sammanfattning : Recent years have witnessed a growing interest of the scientific community for the use of ab initio and density functional theory methods in theoretical studies of molecules containing many atoms. However, the `scaling wall' of some of the most accurate of such methods is often an obstacle for their applicability to systems of real-life interest, e. LÄS MER

  2. 2. Baseband Processing for 5G and Beyond: Algorithms, VLSI Architectures, and Co-design

    Författare :Mojtaba Mahdavi; Institutionen för elektro- och informationsteknik; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; VLSI Implementation; Hardware architectures; ASIC implementation; FPGA implementation; CMOS Technology; Baseband Processing; Massive MIMO; 5G New Radio; Beyond 5G; Co-Design; FFT processor; OFDM modulation; wireless communications; Massive MIMO Detection; Angular domain processing; Zero forcing; Systolic array; Non-linear detector; Channel Sparsity; Channel compression; Linear detector; Channel coding; Spatial coupling; Turbo-like codes; Spatially coupled serially concatenated codes; Threshold analysis; Decoder architecture; BCJR algorithm; MAP algorithm; Coupling memory; Window decoding; Complexity analysis; Performance Evaluation; Throughput; Decoding Latency; Silicon area; Design tradeoffs; Interleaver architecture; Memory requirements; Matrix multiplication; Channel state information CSI ; Cholesky decomposition; Tanner graph; Trellis codes; Convolutional encoder; Code design; Puncturing; Reordering circuit; wireless communication system; digital electronic;

    Sammanfattning : In recent years the number of connected devices and the demand for high data-rates have been significantly increased. This enormous growth is more pronounced by the introduction of the Internet of things (IoT) in which several devices are interconnected to exchange data for various applications like smart homes and smart cities. LÄS MER

  3. 3. Extending the Reach of Accurate Wavefunction Methods

    Författare :Mickaël G. Delcey; Roland Lindh; Per-Åke Malmqvist; Martin Schütz; Uppsala universitet; []
    Nyckelord :NATURAL SCIENCES; NATURVETENSKAP; NATURVETENSKAP; NATURAL SCIENCES; Quantum chemistry; Density fitting; CASSCF; Analytical gradients; Photochemistry; X-ray spectroscopy; Kemi med inriktning mot kvantkemi; Chemistry with specialization in Quantum Chemistry;

    Sammanfattning : Multiconfigurational quantum chemistry methods, and especially the multiconfigurational self-consistent field (MCSCF) and multireference perturbation theory (MRPT2), are powerful tools, particularly suited to the accurate modeling of photochemical processes and transition metal catalysis. However, they are limited by their high computational cost compared to other methods, especially density functional theory. LÄS MER

  4. 4. Genetic epidemiological approaches to the study of risk factors for cardiovascular diseases

    Författare :Anastasia Iliadou; Karolinska Institutet; Karolinska Institutet; []
    Nyckelord :MEDICAL AND HEALTH SCIENCES; MEDICIN OCH HÄLSOVETENSKAP; Twins; cardiovascular diseases; lipids; apolipoproteins; blood pressure; obesity; diabetes mellitus; genetic and environmental components; linkage; association; genetics; epidemiology.;

    Sammanfattning : Cardiovascular disease (CVD) is one of the most common causes of death in most developed countries. Genetic and environmental factors influence CVD and its risk factors in a complex fashion. Parallel to this, new statistical methods are being developed to make use of the new molecular genetic information. LÄS MER

  5. 5. Longitudinal study of the impact on hearing from aging, genetic background and environmental exposures in male twins

    Författare :Renata Bogo; Karolinska Institutet; Karolinska Institutet; []
    Nyckelord :MEDICAL AND HEALTH SCIENCES; MEDICIN OCH HÄLSOVETENSKAP; Male twins; Longitudinal cohort study; Aging; Genetic influences; Hearing loss Tinnitus; Pure–Tone Average; Threshold shift; Prevalence; Incidence proportion; Noise exposure; Job–Exposure Matrix; Occupational work code;

    Sammanfattning : Background: Hearing loss is a process that normally develops over many years, and the ability to hear high–frequency sounds is often reduced first. Age, repeated exposure to loud noise and other risk factors, diseases, medications and injury, can damage the various structures of the ear and interfere with hearing. LÄS MER