Pubications
These publications have been fetched automatically from AAU scientific database. See also the information about the ACABS group on AAU website.
01.
Acoustic chemometric prediction of total solids in bioslurry: A full-scale feasibility study for on-line biogas process monitoring
Ihunegbo, F., Madsen, M., Esbensen, K., Holm-Nielsen, J. B. & Halstensen, M. 2012 I : Chemometrics and Intelligent Laboratory Systems. 110, 1, s. 135-143.Publikation: Forskning - peer review › Tidsskriftartikel
Dry matter is an important process control parameter in the bioconversion application field. Acoustic chemometrics, as a Process Analytical Technology (PAT) modality for quantitative characterisation of dry matter in complex bioslurry systems (biogas fermentation), has not been successful despite several earlier dedicated attempts. A full-scale feasibility study based on standard addition experiments involving natural plant biomass was conducted using multivariate calibration (Partial Least Squares Regression, PLS-R) of acoustic signatures against dry matter content (total solids, TS). Prediction performance of the optimised process implementation was evaluated using independent test set validation, with estimates of accuracy (slope of predicted vs. reference values) and precision (squared correlation coefficient, r2) of 0.94 and 0.97 respectively, with RMSEP of 0.32% w/w (RMSEPrel = 3.86%) in the range of 5.8–10.8% w/w dry matter. Based on these excellent prediction performance measures, it is concluded that acoustic chemometrics has come of age as a full grown PAT approach for on-line monitoring of dry matter (TS) in complex bioslurry, with a promising application potential in other biomass processing industries as well.
| Originalsprog | Engelsk |
|---|---|
| Tidsskrift | Chemometrics and Intelligent Laboratory Systems |
| Udgivelsesdato | 2012 |
| Vol/bind | 110 |
| Tidsskriftsnummer | 1 |
| Sider | 135-143 |
| ISSN | 0169-7439 |
| DOI | |
| Status | Udgivet |
02.
A systematic approach to assessing measurement uncertainty for CO2 emissions from coal-fired power plants – Missing contributions from the Theory of Sampling (TOS)
Wagner, C. & Esbensen, K. nov 2011 I : Chemical Engineering Research & Design. 89, 9, s. 1572-1586. 15 s.Publikation: Forskning - peer review › Tidsskriftartikel
An augmented measurement uncertainty approach for CO2 emissions from coal-fired power plants with a focus on the often forgotten contributions from sampling errors occurring over the entire fuel-to-emission pathway is presented. Current methods for CO2 emission determination are evaluated in detail, from which a general matrix scheme is developed that includes all factors and stages needed for total CO2 determination, which is applied to the monitoring plan of a representative medium-sized coal-fired power plant. In particular sampling involved significant potential errors, as identified and assessed by the Theory of Sampling (TOS), which also shows how these can be eliminated and/or minimised. Since coal-related CO2 emission calculations not only require analytical results of the carbon content of coal itself but also of the by-products fly ash and bottom ash, sampling procedures of these three materials were also given full attention. A systematic error (bias) is present in the current sampling approach, which increases the present uncertainty estimate unnecessarily. For both primary sampling and analytical sample extraction steps, random variations, which hitherto only have been considered to a minor extent, have now also been fully quantified and included in the overall uncertainty. Elimination of all identified sampling errors lead to modified CO2 determination procedures, which indicate that the actual CO2 emission is approximately 20,000 t higher than the present estimate. Based on extensive empirical sampling experiments, a fully comprehensive uncertainty estimate procedure has been devised. Even though uncertainties increased (indeed one particular factor is substantially higher, the so-called “emission factor”), the revised CO2 emission budget for the case plant complies with the official pre-determined uncertainty levels maxima in the EU guidelines.
| Originalsprog | Engelsk |
|---|---|
| Tidsskrift | Chemical Engineering Research & Design |
| Udgivelsesdato | nov 2011 |
| Vol/bind | 89 |
| Tidsskriftsnummer | 9 |
| Sider | 1572-1586 |
| Antal sider | 15 |
| ISSN | 0263-8762 |
| Status | Udgivet |
03.
Principal Component Analysis (PCA): Concept, geometrical intrepretation, mathematical background, algorithms, history
Esbensen, K. & Geladi, P. 2009 Comprehensive Chemometrics. Brown, S., Taulor, R. & Walczak, R. (red.). 2. Oxford : Elsevier Science s. 211-226. 25 s.Publikation: Forskning › Bidrag til bog/antologi
| Originalsprog | Engelsk |
|---|---|
| Titel | Comprehensive Chemometrics : Chemical and Biochemical Data Analysis |
| Redaktører | S. Brown, R. Taulor, R. Walczak |
| Antal sider | 25 |
| Vol/bind | 2 |
| Udgivelsessted | Oxford |
| Udgiver | Elsevier Science |
| Udgivelsesdato | 2009 |
| Sider | 211-226 |
| ISBN (trykt) | 978-0-444-52701-1 |
| DOI | |
| Status | Udgivet |
04.
Chemical imaging and multivariate image analysis
Kucheryavskiy, S. 30 maj 2011Publikation: Forskning › Konferenceabstrakt til konference
| Originalsprog | Engelsk |
|---|---|
| Udgivelsesdato | 30 maj 2011 |
| Antal sider | 1 |
| Status | Udgivet |
05.
Fast algorithm for exploring and compressing of large hyperspectral images
Kucheryavskiy, S. 6 jun 2011Publikation: Forskning - peer review › Paper uden forlag/tidsskrift
A new method for calculation of latent variable space for exploratory analysis and dimension reduction of large hyperspectral images is proposed. The method is based on significant downsampling of image pixels with preservation of pixels’ structure in feature (variable) space. To achieve this, information about pixels density in principal component space for the first two components is utilized. The method was tested on several hyperspectral images and showed significant improvement of performance while the orientation of the latent variables was not very different from the original one. The method can be used first of all for fast compression of large data arrays with principal component analysis or similar projection techniques.
| Originalsprog | Engelsk |
|---|---|
| Udgivelsesdato | 6 jun 2011 |
| Antal sider | 4 |
| DOI | |
| Status | Udgivet |
Workshop
| Workshop | WHISPERS 2011 |
|---|---|
| Land | Portugal |
| By | Lisbon |
| Periode | 06-06-11 → 09-06-11 |
06.
Lyt til dit biogasanlæg
Madsen, M. jun 2011 I : Forskning i Bioenergi, Brint og Brændselsceller. 8, 36, s. 16-17. 2 s.Publikation: Formidling › Tidsskriftartikel
Akustiske og optiske fænomener åbner op for bedre styring af biogasprocessen.
For de største biogasanlæg burde investeringen til akustiske
onlinemålinger kunne tjenes hjem inden for et par måneder,
mens de optiske teknikker er betragteligt dyrere og stiller
andre krav til kalibrering og vedligeholdelse af udstyr.
For de største biogasanlæg burde investeringen til akustiske
onlinemålinger kunne tjenes hjem inden for et par måneder,
mens de optiske teknikker er betragteligt dyrere og stiller
andre krav til kalibrering og vedligeholdelse af udstyr.
| Originalsprog | Dansk |
|---|---|
| Tidsskrift | Forskning i Bioenergi, Brint og Brændselsceller |
| Udgivelsesdato | jun 2011 |
| Vol/bind | 8 |
| Tidsskriftsnummer | 36 |
| Sider | 16-17 |
| Antal sider | 2 |
| ISSN | 1904-6960 |
| Status | Udgivet |
