Sökning: "PCA"

Visar resultat 1 - 5 av 210 avhandlingar innehållade ordet PCA.

  1. 1. Principal Word Vectors

    Författare :Ali Basirat; Joakim Nivre; Hinrich Schütze; Uppsala universitet; []
    Nyckelord :HUMANITIES; HUMANIORA; NATURAL SCIENCES; NATURVETENSKAP; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; NATURVETENSKAP; TEKNIK OCH TEKNOLOGIER; HUMANIORA; NATURAL SCIENCES; ENGINEERING AND TECHNOLOGY; HUMANITIES; word; context; word embedding; principal component analysis; PCA; sparse matrix; singular value decomposition; SVD; entropy;

    Sammanfattning : Word embedding is a technique for associating the words of a language with real-valued vectors, enabling us to use algebraic methods to reason about their semantic and grammatical properties. This thesis introduces a word embedding method called principal word embedding, which makes use of principal component analysis (PCA) to train a set of word embeddings for words of a language. LÄS MER

  2. 2. Prostate Cancer Diagnosis : experimental and Clinical Studies With HRMAS NMR Spectroscopy

    Författare :Katarina Stenman; Katrine Åhlström-Riklund; Anders Bergh; Peter Lundberg; Umeå universitet; []
    Nyckelord :MEDICAL AND HEALTH SCIENCES; MEDICIN OCH HÄLSOVETENSKAP; MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; Prostate cancer; PCa; HRMAS NMR; MRSI; metabolomics; Gleason score; citrate; inositol; choline; Krebs cycle; PUFA; omega-6; omega-3; Diagnostic radiology; Diagnostisk radiologi; Radiology; radiologi;

    Sammanfattning : A few abnormal cells found in a small piece of prostate tissue are most consequential for a man’s future. The prevalence of prostate cancer (PCa) is increasing globally. LÄS MER

  3. 3. Novel Approaches for Application of Principal Component Analysis on Dynamic PET Images for Improvement of Image Quality and Clinical Diagnosis

    Författare :Pasha Razifar; Ewert Bengtsson; Mats Bergström; Harald Schneider; Habib Zaidi; Uppsala universitet; []
    Nyckelord :NATURAL SCIENCES; NATURVETENSKAP; NATURVETENSKAP; NATURAL SCIENCES; Bildanalys; Dynamic PET; Noise Correlation; PCA; Image Quality; Slice-Wise; Pixel-Wise; Masked-Volume-Wise; Pre-normalization; Bildanalys; Image analysis; Bildanalys;

    Sammanfattning : Positron Emission Tomography, PET, can be used for dynamic studies in humans. In such studies a selected part of the body, often the whole brain, is imaged repeatedly after administration of a radiolabelled tracer. LÄS MER

  4. 4. A multivariate approach to computational molecular biology

    Författare :Fredrik Pettersson; Michael Sjöström; Umeå universitet; []
    Nyckelord :NATURAL SCIENCES; NATURVETENSKAP; NATURVETENSKAP; NATURAL SCIENCES; PLS; PCA; biomarker; Drosophila; SNP; linkage; disequilibrium; bioinformatics; computational; molecular; biology; genomics; microarray; SELDI; proteomics; Bioinformatics; Bioinformatik;

    Sammanfattning : This thesis describes the application of multivariate methods in analyses of genomic DNA sequences, gene expression and protein synthesis, which represent each of the steps in the central dogma of biology. The recent finalisation of large sequencing projects has given us a definable core of genetic data and large-scale methods for the dynamic quantification of gene expression and protein synthesis. LÄS MER

  5. 5. Physico-chemical characteristics and quantitative structure-activity relationships of PCBs

    Författare :Patrik Andersson; Stephen Safe; Umeå universitet; []
    Nyckelord :NATURAL SCIENCES; NATURVETENSKAP; polychlorinated biphenyls; PCBs; physico-chemical properties; statistical design; multivariate; PCA; PLS; biomagnification; BMF; bioassay; CYP1A; SAR; QSAR; REPs; risk assessment; Chemistry; Kemi; Chemistry; Kemi;

    Sammanfattning : The polychlorinated biphenyls (PCBs) comprise a group of 209 congeners varying in the number of chlorine atoms and substitution patterns. These compounds tend to be biomagnified in foodwebs and have been shown to induce an array of effects in exposed organisms. LÄS MER