| 1. |
- Löfhede, Johan, 1978, et al.
(författare)
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Detection of bursts in the EEG of post asphyctic newborns
- 2006
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Ingår i: 2006 28th Annual International Conference of the IEEE Engineering in Medicine and Biology Society. - 1557-170X. - 9781424400324 ; , s. 2179-2182, s. 5-6
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Konferensbidrag (refereegranskat)abstract
- Eight features inherent in the electroencephalogram (EEG) have been extracted and evaluated with respect to their ability to distinguish bursts from suppression in burst-suppression EEG. The study is based on EEG from six full term infants who had suffered from lack of oxygen during birth. The features were used as input in a neural network, which was trained on reference data segmented by an experienced electroencephalographer. The performance was then evaluated on validation data for each feature separately and in combinations. The results show that there are significant variations in the type of activity found in burst-suppression EEG from different subjects, and that while one or a few features seem to be sufficient for most patients in this group, some cases require specific combinations of features for good detection to be possible.
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| 2. |
- Löfhede, Johan, et al.
(författare)
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Classification of burst and suppression in the neonatal electroencephalogram
- 2008
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Ingår i: Journal of Neural Engineering. - : Institute of Physics Publishing Ltd.. - 1741-2560 .- 1741-2552. ; 5:4, s. 402-410
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Tidskriftsartikel (refereegranskat)abstract
- Fisher's linear discriminant (FLD), a feed-forward artificial neural network (ANN) and a support vector machine (SVM) were compared with respect to their ability to distinguish bursts from suppressions in electroencephalograms (EEG) displaying a burst-suppression pattern. Five features extracted from the EEG were used as inputs. The study was based on EEG signals from six full-term infants who had suffered from perinatal asphyxia, and the methods have been trained with reference data classified by an experienced electroencephalographer. The results are summarized as the area under the curve (AUC), derived from receiver operating characteristic (ROC) curves for the three methods. Based on this, the SVM performs slightly better than the others. Testing the three methods with combinations of increasing numbers of the five features shows that the SVM handles the increasing amount of information better than the other methods.
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| 3. |
- Löfhede, Johan, et al.
(författare)
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Comparing a Supervised and an Unsupervised Classification Method for Burst Detection in Neonatal EEG
- 2008
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Ingår i: Proceedings of Engineering in Medicine and Biology Society, EMBS 2008. 30th Annual International Conference of the IEEE, 20-24 August, 2008. - : IEEE. - 1557-170X. - 9781424418145 ; , s. 3836-3839
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Konferensbidrag (refereegranskat)abstract
- Hidden Markov Models (HMM) and Support Vector Machines (SVM) using unsupervised and supervised training, respectively, were compared with respect to their ability to correctly classify burst and suppression in neonatal EEG. Each classifier was fed five feature signals extracted from EEG signals from six full term infants who had suffered from perinatal asphyxia. Visual inspection of the EEG by an experienced electroencephalographer was used as the gold standard when training the SVM, and for evaluating the performance of both methods. The results are presented as receiver operating characteristic (ROC) curves and quantified by the area under the curve (AUC). Our study show that the SVM and the HMM exhibit similar performance, despite their fundamental differences.
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| 4. |
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| 5. |
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| 6. |
- Bengtsson, Lars, 1963
(författare)
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Signalbehandling
- 2003
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Ingår i: Tabeller och Formler. - Stockholm : Liber AB. - 9147050926 ; , s. 355-360
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Bokkapitel (övrigt vetenskapligt/konstnärligt)abstract
- Denna formel- och tabellsamling innehåller grundläggande definitioner, tabeller och formler inom det naturvetenskapliga och tekniska området. Boken är lämplig för högskoleingenjörsutbildning och grundläggande utbildningar för civilingenjörer. Författarnas inriktning har varit att ge boken en sådan bredd att den också kan användas som referenslitteratur på gymnasiet.
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| 7. |
- Johansson, Erika, 1969, et al.
(författare)
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Towards Sustainable Conservation and Use of Materials in Built Environments : Summary from the FORSCENE workshop: Industry/Economy, Vienna, October 23-24, 2006
- 2007
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Ingår i: Giljum, S., Hinterberger, F., Hammer, M. (Eds.), Report from the FORSCENE workshop Industry-Environment, Sustainable Europe Research Institute (SERI), Vienna, October 2006, Part 2..
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Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- Up until today, no comprehensive efforts have been made, and principles are yet to be established for the ‘sustainable conservation’ of the built environment – in an inter- and transdisciplinary manner, including systematic integrative modelling and an appreciation of the inherent values of already existing structures and ambiences. Existing built structures and environments are still often seen as obstacles for sustainable development. It may be argued that a more preventive and integrated approach, i.e. an early estimation and a meta-level understanding of the built environment and its processes; its critical loads, inherent qualities, values, threats, life cycles, production chains, recyclability and quantities etc., would rather promote any kind of planning for a sustained future and the proper use of materials by hindering unnecessary material flows - i.e. through their unnecessary/unsympathetic production, exploitation and/or use, that would minimise their negative impact on peoples lives and the environment. This alternative and more preventative approach - earlier the predominant way of handling urban planning, construction and development (i.e. the production and utilisation of both existing and planned for resources, e.g. by the use of high quality production technologies and crafts, processes and skills), was historically much based on the valorisation of costs of manpower, materials, traditional knowledge, techniques and low-energy modes of transportation, compared to modern circumstances. There was also a profound knowledge of economics in more general terms and a well-developed forecasting of future scenarios. Given the demands for a sustained future, it would be reasonable to assume that this knowledge and approach would have a great deal to offer also to the planning and epistemological modelling of our times.
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| 8. |
- Berglin, Mattias, 1970, et al.
(författare)
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Use of surface-sensitive methods for the study of adsorption and cross-linking of marine bioadhesives
- 2005
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Ingår i: Journal of Adhesion. - : Informa UK Limited. - 0021-8464 .- 1563-518X .- 1545-5823. ; 81:7-8, s. 805-822
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Tidskriftsartikel (refereegranskat)abstract
- The establishment of the bond of sessile marine organisms such as barnacles, mussels, and algae in the marine environment starts with the secretion and the adsorption of the adhesive biopolymers to the substrate. Subsequently, this is followed by the formation of cohesive interactions with the next layer of adhesive biopolymers that are deposited/adsorbed on top of the first layer. These two fundamental processes for the adhesive plaque buildup have been subjected to several investigations in recent years using model molecules, especially Mefp-1 extracted from the blue mussel Mytilus edulis. With the introduction of optical surface-sensitive methods such as ellipsometry, surface plasmon resonance (SPR), and infrared spectroscopy (IR), it has been possible to elucidate both the kinetics of adsorption and structure of the Mefp-1 film. In contrast to adsorption, the cohesive interactions or the cross-linking are not easily followed with these optical methods and new approaches and techniques are required. One such technique that has been useful is the quartz-crystal microbalance with dissipation monitoring (QCM-D), which has been used for cross-linking studies of a variety of biopolymers including bioadhesives from mussel and algae. Copyright © Taylor & Francis Inc.
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| 10. |
- Ballerini, Lucia, et al.
(författare)
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Comparison of histomorphometrical data obtained with two different image analysis methods
- 2007
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Ingår i: Journal of materials science. Materials in medicine. - : Springer. - 0957-4530 .- 1573-4838. ; 18:8, s. 1471-1479
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Tidskriftsartikel (refereegranskat)abstract
- A common way to determine tissue acceptance of biomaterials is to perform histomorphometrical analysis on histologically stained sections from retrieved samples with surrounding tissue, using various methods. The “time and money consuming” methods and techniques used are often “in house standards”. We address light microscopic investigations of bone tissue reactions on un-decalcified cut and ground sections of threaded implants. In order to screen sections and generate results faster, the aim of this pilot project was to compare results generated with the in-house standard visual image analysis tool (i.e., quantifications and judgements done by the naked eye) with a custom made automatic image analysis program. The histomorphometrical bone area measurements revealed no significant differences between the methods but the results of the bony contacts varied significantly. The raw results were in relative agreement, i.e., the values from the two methods were proportional to each other: low bony contact values in the visual method corresponded to low values with the automatic method. With similar resolution images and further improvements of the automatic method this difference should become insignificant. A great advantage using the new automatic image analysis method is that it is time saving—analysis time can be significantly reduced.
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