Zobrazeno 1 - 10
of 14
pro vyhledávání: '"Jorgen L. Nikolajsen"'
Autor:
Jorgen L. Nikolajsen
Publikováno v:
Royal Society Open Science, Vol 1, Iss 2 (2014)
A set of simple stopping criteria is presented, which improve the efficiency of iterative root finding by terminating the iterations immediately when no further improvement of the roots is possible. The criteria use only the function evaluations alre
Externí odkaz:
https://doaj.org/article/41c0cf45ea3b43eaa8656d63c56881a7
Autor:
Jorgen L. Nikolajsen
Publikováno v:
SIAM Journal on Scientific Computing. 35:A561-A576
The concept of fractional significant digits is explored and a definition is proposed, which puts the concept on a firm analytical footing. A simple, reliable procedure is derived for calculating the number of fractional significant digits with high
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::f3727275fee761a209778c9351047464
https://doi.org/10.1137/110828435
https://doi.org/10.1137/110828435
Autor:
Jorgen L. Nikolajsen
Publikováno v:
SIAM Journal on Scientific Computing. 22:822-834
A Laguerre iteration procedure is described for finding the eigenvalues of unsymmetric matrices with improved efficiency. Compared to the QR method, the processing time for dense matrices is reduced by roughly a factor of 1.6 and for sparse matrices
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::55ab349a4e71b865d83721dbf2954604
https://doi.org/10.1137/s106482759834963x
https://doi.org/10.1137/s106482759834963x
Autor:
Jorgen L. Nikolajsen
Publikováno v:
Tribology Transactions. 42:186-191
Analytical models are derived for the viscosity and the density of aerated oil in fluid-film bearings. The models account for the effects of fluid-film pressure, fluid-film geometry, oil aeration rate and bubble surface tension. The viscosity model c
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::7bb3fceb80350db6c211c1d551f1c0be
https://doi.org/10.1080/10402009908982207
https://doi.org/10.1080/10402009908982207
Autor:
Jorgen L. Nikolajsen
Publikováno v:
Tribology Transactions. 42:58-62
The load capacity of a plain journal bearing is calculated using newly derived analytical models for the density and the viscosity of aerated oil. The results show that oil aeration can double the load capacity of plain journal bearings. This is due
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::56e8ae1cebbed697efae5986dbe6d20a
https://doi.org/10.1080/10402009908982190
https://doi.org/10.1080/10402009908982190
Autor:
Jorgen L. Nikolajsen
Publikováno v:
Volume 4: Manufacturing Materials and Metallurgy; Ceramics; Structures and Dynamics; Controls, Diagnostics and Instrumentation; Education; IGTI Scholar Award.
A quantitative comparison is made between the Finite Element Method and four variants of the Transfer Matrix Method, as applied to free vibration analysis of rotor systems. The results are as follows: The Finite Element Method is the most robust meth
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::1e5ed8926aca15141fe7fb457e75cd29
https://doi.org/10.1115/2001-gt-0234
https://doi.org/10.1115/2001-gt-0234
Publikováno v:
Volume 4: Manufacturing Materials and Metallurgy; Ceramics; Structures and Dynamics; Controls, Diagnostics and Instrumentation; Education; IGTI Scholar Award; General.
This paper describes some of the requirements for bearing dampers to be used in an aircraft engine and briefly discusses the pros and cons of various types of dampers that were considered as candidates for active control in aircraft engines. A disk t
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::95e7b2ea1e406e5148d2259e4c34ec2a
https://doi.org/10.1115/99-gt-018
https://doi.org/10.1115/99-gt-018
Publikováno v:
Volume 4: Manufacturing Materials and Metallurgy; Ceramics; Structures and Dynamics; Controls, Diagnostics and Instrumentation; Education; IGTI Scholar Award.
The Fast Wavelet Transform (FWT) is a powerful new tool which can be used for vibration analysis and condition monitoring of advanced rotating machinery. The main advantage of wavelet analysis for condition monitoring is that so-called wavelet maps c
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::ad97a86d974692c9da6f14670f33262d
https://doi.org/10.1115/97-gt-058
https://doi.org/10.1115/97-gt-058
Autor:
M. S. Hoque, Jorgen L. Nikolajsen
Publikováno v:
Vibration and Wear in High Speed Rotating Machinery ISBN: 9789401073547
A new type of vibration damper for rotor systems has been developed and tested. The damper contains electroviscous fluid which solidifies and provides Coulomb damping when an electric voltage is imposed across the fluid. The damping capacity is contr
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::3748283907e66dadde2ed27c15fb7e65
https://doi.org/10.1007/978-94-009-1914-3_25
https://doi.org/10.1007/978-94-009-1914-3_25
Autor:
Jorgen L. Nikolajsen
Publikováno v:
Magnetic Bearings ISBN: 9783642517266
An AC-electromagnetic bearing based on eddy-current repulsion has been built and tested. The bearing was found to be inherently stable and able to provide support in five degrees of freedom, i.e. a short rotor was fully supported by a single bearing
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::2368c958ab6b3103202611f195f262ce
https://doi.org/10.1007/978-3-642-51724-2_11
https://doi.org/10.1007/978-3-642-51724-2_11