... Abstract A simultaneous Distributed Acoustic Sensing (DAS) and Distributed Temperature Sensing (DTS) system is presented. In DAS, perturbations across hundreds of metres of fibre are detected by the use of phase-sensitive Optical Time-Domain Reflectometry (OTDR) from Rayleigh backscattering...

... condition friction residual curvature section perturbation installation residual curvature endal offshore pipeline upstream oil & gas pendulum lateral rotate curvature tdp pipeline rotation reference rotation instability straightness Prediction of Pipeline Rotation During...

... of motion path deviations on impact loads and free surface perturbations and shapes are discussed. INTRODUCTION In the past, the influence of pressure sensor type and model as well as data acquisition rates have been under intense investigation in the field of impact load related topics like sloshing...

... even for long duration tests. Thus, if a small uncertainty window is introduced, impacts always happen at the same instants when the same condition is repeated. They are referred to as coincident impacts. The impact time is their impact ID. The random perturbations brought to the flow...

... for the effects of current gradient on the nonlinear dynamics of the ocean surface near blocking point. Using a split-step scheme we show that the extended NLSE of Smith is unstable against random chaotic perturbation in the current profile. Therefore the monochromatic wave field with unit amplitude turns...

... sediment simulations continued over the new bed geometry. A typical result of ripple creation, merging and annihilation, is shown in Fig. 7 for oscillatory flow over a flat bed with an initial perturbation in the middle of the flow field, at Re = 5,000. The non-dimensional domain length was equal to 3...

... identification proximity intensity production logging noise generation perturbation acoustic perturbation upstream oil & gas acoustic analogy artificial intelligence contribution analogy indirect approach production monitoring Experimental Methodologies For Noise Source Diagnostics In Marine...

... and strength on acoustic propagation (Robertson et al. , 1985). However, these parabolic equations are restricted to two dimensions. parabolic equation transmission loss dimension cross angle perturbation receiver propagation variation eddy parabolic approximation south china sea robertson...

..., correction terms in the transport equations of the κ- closure model has been implemented to compensate the turbulence equilibrium perturbation. By counter-balancing the enhanced kinetic turbulent energy (TKE), these terms shall account for the generation of extra-velocity shear induced by the presence...

... cycle oscillations by adjusting the nonlinear feedback in the system. Limit cycles of the oscillator controller generate swimming patterns that resist perturbations and therefore the BAUV could swim stably. Increasing the swimming efficiency could be achieved by using actuators that drive motions...

... devices, determine only local perturbations. If these perturbations are interlinked with long-period processes of a global scale, it is possible to assume presence of correlation between drift in local points and on the basis of the considerable expansion. Thus, the integrated approach to a solution...

... matrix was studied during the model tests. As shown in Table 6, all the various design seastates, along with their perturbations on Hs and Tp were tested. Additionally, two crest-based seastates, i.e. seastates that were specifically calibrated to result in the correct design crest, were tested...

... of this paper is to document a preliminary review, primarily theoretical, focusing on geotechnical aspects. subsea system upstream oil & gas foundation spudcan-footprint interaction th int conf perturbation deployment spudcan drilling equipment interaction footprint trajectory...

... is sought in both regions satisfying the matching pressure and normal velocity conditions between the internal and external fluid regions, and zero normal velocity conditions on the rigid boundary. The method of solution is based on perturbation theory, using a perturbation parameter defined in terms...

... perturbation nonlinear roll amplitude amplitude characteristic exponent upright position perturbation ship mathieu equation instability zone Proceedings of the Eleventh (2001) International Offshore and Polar Engineering Conference Stavanger, Norway, June 17-22, 2001 Copyright © 2001...

... equation to investigate and demonstrate response probabilistic characteristics. With the presence of weak perturbations, highly nonlinear phenomena including coexistence of attractors and chaos are found to exist. It is indicated that the presence of noise expands the potential chaotic domain...

... nonlinear wave instability perturbation instability wave steepness steepness Proceedings of the Seventh (1997) International Offshore and Polar Engineering Conference Honolulu, USA, May 25-30, 1997 Copyright © 1997 by The International Society of Offshore and Polar Engineers ISBN 1-880653-28.1 (Set...

... in the atmosphere are viewed by many as perhaps the most serious global environmental problem facing mankind. If irreversible changes in the global climate system are triggered by the increased greenhouse ffect caused by CO_, and other gases whose natural cycles have been perturbed, conditions for future...

..., with their associated hysteresis for an axially preloaded spiral strand experiencing superimposed (external) uniform cyclic load perturbations, and axial or restrained bending fatigue life. Using a series of theoretical parametric studies on a large number of spiral strands with widely varying strand (and wire...

... validation drift current altimeter renewable energy metocean model wind field procedure perturbation latitude determination satellite measurement metocean input data Proceedings of the Fifth (1995) International Offshore and Polor Engineering Conference The Hague, The Netherlonds,June 11-16...