Results 211 to 220 of about 116,428 (235)

Nonlinear roll damping parameter identification using free-decay data

Ocean Engineering, 2021
Abstract A common practice for evaluating the nonlinear damping in ship roll motion is to perform a free-decay experiment. Although various methods have been developed to estimate the coefficients of a nonlinear damping model, these methods are limited to certain and relatively simple models.
Huajun Li, Sau-Lon James Hu, Jinwei Sun
openaire   +2 more sources

The decay of stresses induced by flat rolling of metal strip

International Journal of Mechanical Sciences, 1993
Abstract Current simulation models for the prediction of residual stresses in flat metal rolling utilize heuristic assumptions about the roll-gap entrance and exit velocity distributions. The nature of the velocity distributions which occur in the strip adjoining the roll-gap is investigated.
Donald McElwain, S. A. Domanti, Richard H. Middleton, W.J. Edwards   +3 more
openaire   +2 more sources

Expected Time Value Decay of Options: Implications for Put‐Rolling Strategies [PDF]

Financial Review, 2008
AbstractAssuming the underlying asset price remains constant, previous studies show that the time value of an option decays gradually at a rate that accelerates over time and peaks at the expiration date. Thus, a significant portion of time value is lost in the four weeks leading up to expiration.
Clifton Lee-Sing, George F. Tannous
openaire   +1 more source

Martensite decay during rolling contact fatigue in ball bearings

Metallurgical Transactions A, 1976
During rolling contact fatigue of ball bearings structural changes may occur below the raceway, in the region of maximum shear stress. A great number of 6309 type bearings were tested at two stress levels for varying numbers of revolutions, and the resulting structural changes in the inner rings were studied by optical and electron microscopy.
Olof Vingsbo, P. C. Becker, H. Swahn
openaire   +2 more sources

Application of wavelet transforms to the decoupling of free-roll decay data

Ocean Engineering, 2003
This study presents the results of the decoupling of a free-roll decay test by wavelet transforms. A free-roll decay test was performed to determine the coefficients of damping terms in equations of motion. No motion of the model was restricted during the experiment. A slight yaw motion was found while the model was in the free-roll decay motion.
Dae-Woong Kim, Hee Seob Lee, Soon-Goo Kwon   +2 more
openaire   +2 more sources

Free Roll Decay Study of a Damaged Ship for CFD Validation

Volume 6: Ocean Engineering, 2011
Among many factors to be considered for higher safety level requirements, the hull stability in intact and damaged conditions in seaway is of utmost importance. Since the assessment of the damaged stability is complicated due to the highly non-linear behavior, it is widely acknowledged that computational fluid dynamics (CFD) methods are the only viable
Hyun-Ho Lee, Key-Pyo Rhee, Ji-Myoung You, Shin Hyung Rhee, Sungkyun Lee   +4 more
openaire   +2 more sources

Experimental and numerical estimation on roll damping and pressure on a 2-D rectangular structure in free roll decay test

Ocean Engineering, 2020
Abstract Experimental and numerical studies were performed to estimate roll damping and hydrodynamic pressure on a 2-D rectangular structure. Free roll decay test was simulated by experiment in 2-D wave tank with Particle Image Velocimetry (PIV) measurement, and by numerical simulations using CFD based on an unsteady incompressible Reynolds-Averaged ...
Gang Nam Lee, Tien Trung Duong, Il-Ryong Park, Sung-Bu Suh, Mingyu Kim, Kwang Hyo Jung, Sung Boo Park   +6 more
openaire   +2 more sources

An Exponential Decay Model for Decaying of Contact Patch Friction Steering Moment with Rolling Speed

Tire Science And Technology
ABSTRACT Steering torque is a very important quantity for the driver's response. In fact, it gives the driver an idea of the road adherence condition during driving. Several models have been developed to simulate shear forces at the contact patch; most of them are based on semi-empirical tire models that account for slip and slip angles.
Jai Prakash, Michele Vignati, Edoardo Sabbioni   +2 more
openaire   +1 more source

Estimation of ship roll damping—A comparison of the decay and the harmonic excited roll motion technique for a post panamax container ship

Ocean Engineering, 2016
The decay motion as well as the harmonic excited roll motion are established techniques to estimate roll damping for ships. This paper compares the advantages and disadvantages of both techniques and focuses on their applicability. Different analysis methods for both techniques to determine the nonlinear roll damping moment are investigated with the ...
Moustafa Abdel-Maksoud, Sven Wassermann, Dag-Frederik Feder   +2 more
openaire   +2 more sources

Measuring the coefficients of kinetic and rolling friction by exploring decaying mass-spring oscillations [PDF]

Physics Education, 2017
A novel method of measuring the coefficients of kinetic and rolling friction is proposed. The method is simple to implement and reliable. Samples of measurements and calculations are presented.
Leonard Minkin, Daniel Sikes
openaire   +1 more source