Sigurdur Olafsson

Dr. Sigurdur Olafsson

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Research Focus & Metrics

Academic Career Length

24Years (2003-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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1 December 2005 in Journal of Scheduling
Verified
Journal Article
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XLXiaonan Li
Xiaonan Li
SOSigurdur Olafsson
Sigurdur Olafsson

1 March 2004 in Methodology and Computing in Applied Probability
Verified
Journal Article
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SOSigurdur Olafsson
Sigurdur Olafsson

23 July 2014 in European Journal of Public Health
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Journal Article
Open access
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TTThorarinn Tyrfingsson
Thorarinn Tyrfingsson
SOSigurdur Olafsson
Sigurdur Olafsson
EBEinar Bjornsson
Einar Bjornsson
VRVilhjalmur Rafnsson
Vilhjalmur Rafnsson
Background: The objectives were to study alcohol consumption per capita and liver cirrhosis mortality in the population of Iceland. Methods: The Statistic Iceland website supplied alcohol sales figures and death rates. Results: The alcohol consumption increased 30% during the study period 1982–2009, because of increase in beer and wine, and decrease in spirits consumption. Chronic liver cirrhosis mortality increased significantly for men when comparing the 1982–88 rates (before beer ban was lifted) with the rates for 2003–09. Conclusion: The findings do not support the suggestion that spirits consumption rather than the total alcohol consumption affect the cirrhosis mortality.

10 September 2006
Verified
Book Chapter
Closed access
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JLJun-Youl Lee
Jun-Youl Lee
SOSigurdur Olafsson
Sigurdur Olafsson

20 November 2024 in Automation
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Journal Article
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MMMohammad Mohammadzadeh
Mohammad Mohammadzadeh
GKGül E. Kremer
Gül E. Kremer
SOSigurdur Olafsson
Sigurdur Olafsson
PKPaul Kremer
Paul Kremer
Detecting cracks in cylinder heads traditionally relies on manual inspection, which is time-consuming and susceptible to human error. As an alternative, automated object detection utilizing computer vision and machine learning models has been explored. However, these methods often face challenges due to a lack of sufficiently annotated training data, limited image diversity, and the inherently small size of cracks. Addressing these constraints, this paper introduces a novel automated crack-detection method that enhances data availability through a synthetic data generation technique. Unlike general data augmentation practices, our method involves copying cracks from one location to another, guided by both random and informed engineering decisions about likely crack formations due to cyclic thermomechanical loads. The innovative aspect of our approach lies in the integration of domain-specific engineering knowledge into the synthetic generation process, which substantially improves detection accuracy. We evaluate our method’s effectiveness using two metrics: the F2 score, which emphasizes recall to prioritize detecting all potential cracks, and mean average precision (MAP), a standard measure in object detection. Experimental results demonstrate that, without engineering insights, our method increases the F2 score from 0.40 to 0.65, while maintaining a stable MAP. Incorporating detailed engineering knowledge further enhances the F2 score to 0.70 and improves MAP to 0.57, representing increases of 63% and 43%, respectively. These results confirm that our approach not only mitigates the limitations of traditional data augmentation but also significantly advances the reliability and precision of crack detection in industrial settings.

18 December 2008
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Book Chapter
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LSLeyuan Shi
Leyuan Shi
SOSigurdur Olafsson
Sigurdur Olafsson