Sökning: "PLS"

Visar resultat 6 - 10 av 144 avhandlingar innehållade ordet PLS.

1. 6. Prediction of wood species and pulp brightness from roundwood measurements

   Författare :David Nilsson; Ulf Edlund; Michael Sjöström; Olav Kvalheim; Umeå universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Design of Experiments; ISO brightness; Multivariate Image Analysis; Multivariate Modelling; NIR spectroscopy; Norway spruce; PCA; PLS; Roundwood; Scots pine; Organic chemistry; Organisk kemi;

   Sammanfattning : This thesis presents a number of studies, where a multivariate approach was taken to construct models that predict wood species and thermo mechanical pulp brightness from roundwood of Norway spruce and Scots pine. The first and second studies produced multivariate prediction models for wood species from the bark of spruce and pine. LÄS MER

3. 7. Improving interpretation by orthogonal variation : Multivariate analysis of spectroscopic data

   Författare :Hans Stenlund; Johan Trygg; Tom Fearn; Umeå universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; OPLS; PLS; Multivariate Analysis; Orthogonal variation; Chemometrics; hyperspectral images; FTIR; NIR; spectroscopy; Chemistry; Kemi;

   Sammanfattning : The desire to use the tools and concepts of chemometrics when studying problems in the life sciences, especially biology and medicine, has prompted chemometricians to shift their focus away from their field‘s traditional emphasis on model predictivity and towards the more contemporary objective of optimizing information exchange via model interpretation. The complex data structures that are captured by modern advanced analytical instruments open up new possibilities for extracting information from complex data sets. LÄS MER

4. 8. Development of an Environment-Accident Index : A planning tool to protect the environment in case of a chemical spill

   Författare :Åsa Scott Andersson; Mats Tysklind; Ingrid Fängmark; Olof Stjernström; Stellan Fisher; Per Leffler; Ronald Wennersten; Umeå universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Environmental chemistry; Environment-Accident Index; Chemical Accidents; environmental effects; questionnaire; expert judgements; statistical multivariate design; PCA; PLS; Miljökemi; Environmental chemistry; Miljökemi;

   Sammanfattning : The increasing mass and complexity of chemicals being produced and transported has resulted in more rigorous demands on both authorities as well as chemical-handling industries to assess the risks involved. The Environment-Accident Index (EAI), has been proposed as a planning tool created as an equation in which chemical properties (variables describing the chemical involved) are combined with site-specific properties (variables describing the accident site). LÄS MER

5. 9. Multivariate spectroscopic methods for the analysis of solutions

   Författare :Kent Wiberg; Sven Jacobsson; Lars Nørgaard; Stockholms universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Chemometrics; UV-Vis spectroscopy; Multivariate calibration; Lidocaine; Identity; Content; PLS; SIMCA; Non-column; Diode array UV spectroscopy; DAD; Control sample; High Capacity Analysis HCA ; Fluorescence spectroscopy; Albumin; Immunoglobulin G; HPLC-DAD; Prilocaine; Peak purity determination; PCA; PARAFAC; Partial separation; Curve resolution; Analytical chemistry; Analytisk kemi;

   Sammanfattning : In this thesis some multivariate spectroscopic methods for the analysis of solutions are proposed. Spectroscopy and multivariate data analysis form a powerful combination for obtaining both quantitative and qualitative information and it is shown how spectroscopic techniques in combination with chemometric data evaluation can be used to obtain rapid, simple and efficient analytical methods. LÄS MER

7. 10. Structural Elements in Native Celluloses

   Författare :Kristina Wickholm; KTH; []
   Nyckelord :cellulose I; accessible fibril surfaces; inaccessible fibril surfaces; para-crystalline cellulose; fibril aggregates; CP MAS 13C-NMR spectroscopy; spectral fitting; PCA; PLS;

   Sammanfattning : In this thesis, a schematic model for the structure ofaggregated cellulose I fibrils is proposed. The model consistsof a crystalline fibril core surrounded by less orderedcellulose forms. These cellulose forms are fibril surfacesaccessible to water, fibril surfaces inaccessible to water andpara-crystalline cellulose. LÄS MER