0
Journal of Offshore Mechanics and Arctic Engineering | Volume 131 | Issue 4 | Ocean Engineering
Ocean Engineering

Statistics of Extreme Events in Airgap Measurements

[+] Author and Article Information
A. Naess

Department of Mathematical Sciences, Centre for Ships and Ocean Structures, Norwegian University of Science and Technology, NO-7491 Trondheim, Norwayarvidn@math.ntnu.no

C. T. Stansberg

 MARINTEK, NO-7450 Trondheim, Norwaycarl.t.stansberg@marintek.sintef.no

O. Gaidai

 MARINTEK, NO-7450 Trondheim, Norwayoleg.gaidai@marintek.sintef.no

R. J. Baarholm

 MARINTEK, NO-7450 Trondheim, Norwayrolf.j.baarholm@marintek.sintef.no

J. Offshore Mech. Arct. Eng 131(4), 041107 (Oct 01, 2009) (8 pages) doi:10.1115/1.3160652 History: Received March 18, 2008; Revised February 25, 2009; Published October 01, 2009
Article
References
Figures
Tables
Citing Articles

The paper presents a study of the extreme value statistics related to airgap measurements on a scale model of a semisubmersible platform subjected to random waves in a wave basin. Relative wave elevation records corresponding to totally 24 h storm duration are considered, made up by 8×3 h realizations. The focus is on a comparison of two alternative methods for the prediction of extreme values from finite recordings at two different locations at the platform. One is a standard method used in the wave basin, making use of a Weibull-tail fitting procedure. The other is a novel method based on the level upcrossing function combined with an optimization procedure that allows prediction at extreme response levels. Similar results are obtained in the mean values by the two methods, while the latter shows less variability in the predictions from single 3 h records.
Copyright © 2009 by American Society of Mechanical Engineers
Your Session has timed out. Please sign back in to continue.

References

Figures

Grahic Jump Location
+Schematic of the problem (see Ref. 3)
View Large  |  Save Figure  |  Download Slide (.ppt)
Schematic of the problem (see Ref. 3)
Figure 1

Schematic of the problem (see Ref. 3)

Grahic Jump Location
+Bird’s eye view of the case study geometry. Wave probe locations used in this presentation are highlighted in Ref. 3.
View Large  |  Save Figure  |  Download Slide (.ppt)
Bird’s eye view of the case study geometry. Wave probe locations used in this presentation are highlighted in Ref. 3.
Figure 2

Bird’s eye view of the case study geometry. Wave probe locations used in this presentation are highlighted in Ref. 3.

Grahic Jump Location
+Snapshot from the ocean basin tests of the Kristin semisubmersible
View Large  |  Save Figure  |  Download Slide (.ppt)
Snapshot from the ocean basin tests of the Kristin semisubmersible
Figure 3

Snapshot from the ocean basin tests of the Kristin semisubmersible

Grahic Jump Location
+Power spectra, 24 h records
View Large  |  Save Figure  |  Download Slide (.ppt)
Power spectra, 24 h records
Figure 4

Power spectra, 24 h records

Grahic Jump Location
+Amplitude distribution, relative wave 8, and 3 h realization
View Large  |  Save Figure  |  Download Slide (.ppt)
Amplitude distribution, relative wave 8, and 3 h realization
Figure 5

Amplitude distribution, relative wave 8, and 3 h realization

Grahic Jump Location
+Amplitude distribution, relative wave 8, and 24 h realization
View Large  |  Save Figure  |  Download Slide (.ppt)
Amplitude distribution, relative wave 8, and 24 h realization
Figure 6

Amplitude distribution, relative wave 8, and 24 h realization

Grahic Jump Location
+Plot of the 3 h extreme values from measurements and the Weibull fit for relative wave 1
View Large  |  Save Figure  |  Download Slide (.ppt)
Plot of the 3 h extreme values from measurements and the Weibull fit for relative wave 1
Figure 7

Plot of the 3 h extreme values from measurements and the Weibull fit for relative wave 1

Grahic Jump Location
+Plot of the 3 h extreme values from measurements and the Weibull fit for relative wave 8
View Large  |  Save Figure  |  Download Slide (.ppt)
Plot of the 3 h extreme values from measurements and the Weibull fit for relative wave 8
Figure 8

Plot of the 3 h extreme values from measurements and the Weibull fit for relative wave 8

Grahic Jump Location
+Crossing rate log plot with extrapolation, 24 h, and relative wave 1
View Large  |  Save Figure  |  Download Slide (.ppt)
Crossing rate log plot with extrapolation, 24 h, and relative wave 1
Figure 9

Crossing rate log plot with extrapolation, 24 h, and relative wave 1

Grahic Jump Location
+Optimal transformed plot, 24 h, and relative wave 1
View Large  |  Save Figure  |  Download Slide (.ppt)
Optimal transformed plot, 24 h, and relative wave 1
Figure 10

Optimal transformed plot, 24 h, and relative wave 1

Grahic Jump Location
+Crossing rate log plot with extrapolation, 24 h, and relative wave 8
View Large  |  Save Figure  |  Download Slide (.ppt)
Crossing rate log plot with extrapolation, 24 h, and relative wave 8
Figure 11

Crossing rate log plot with extrapolation, 24 h, and relative wave 8

Grahic Jump Location
+Optimal transformed plot, 24 h, and relative wave 8
View Large  |  Save Figure  |  Download Slide (.ppt)
Optimal transformed plot, 24 h, and relative wave 8
Figure 12

Optimal transformed plot, 24 h, and relative wave 8

Grahic Jump Location
+Plot of the 3 h extreme value from measurements and the predicted MPM for relative wave 1
View Large  |  Save Figure  |  Download Slide (.ppt)
Plot of the 3 h extreme value from measurements and the predicted MPM for relative wave 1
Figure 13

Plot of the 3 h extreme value from measurements and the predicted MPM for relative wave 1

Grahic Jump Location
+Plot of the 3 h extreme value from measurements and the predicted MPM for relative wave 8
View Large  |  Save Figure  |  Download Slide (.ppt)
Plot of the 3 h extreme value from measurements and the predicted MPM for relative wave 8
Figure 14

Plot of the 3 h extreme value from measurements and the predicted MPM for relative wave 8

Grahic Jump Location
+Plot of the 3 h extreme value from measurements and the predicted 90% fractile extreme for relative wave 1
View Large  |  Save Figure  |  Download Slide (.ppt)
Plot of the 3 h extreme value from measurements and the predicted 90% fractile extreme for relative wave 1
Figure 15

Plot of the 3 h extreme value from measurements and the predicted 90% fractile extreme for relative wave 1

Grahic Jump Location
+Plot of the 3 h extreme value from measurements and the predicted 90% fractile extreme for relative wave 8
View Large  |  Save Figure  |  Download Slide (.ppt)
Plot of the 3 h extreme value from measurements and the predicted 90% fractile extreme for relative wave 8
Figure 16

Plot of the 3 h extreme value from measurements and the predicted 90% fractile extreme for relative wave 8

Tables

Errata

Discussions

Some tools below are only available to our subscribers or users with an online account.

Related Content

Customize your page view by dragging and repositioning the boxes below.

Related Journal Articles
Related eBook Content
A Compact Circularly Polarized Microstrip Antenna for UHF RFID Readers
International Conference on Instrumentation, Measurement, Circuits and Systems (ICIMCS 2011)
Geophysical Data Processing and Identifying for Gas Hydrate in the Slope of South China Sea
International Conference on Electronics, Information and Communication Engineering (EICE 2012)
International Cooperation Practice Model in Vocational and Technical University
International Conference on Electronics, Information and Communication Engineering (EICE 2012)
New Aspects of Measurement Techniques and Management Systems for QoS in VoIP
International Conference on Instrumentation, Measurement, Circuits and Systems (ICIMCS 2011)
Research on Fitting Model of the Human Body Based on Remote Image Feature Recognition
International Symposium on Information Engineering and Electronic Commerce, 3rd (IEEC 2011)
Topic Collections

Sorry! You do not have access to this content. For assistance or to subscribe, please contact us:

  • TELEPHONE: 1-800-843-2763 (Toll-free in the USA)
  • EMAIL: asmedigitalcollection@asme.org
Sign In