This paper discusses the problem of Adaptive heave compensation. A new estimator based on dynamic recurrent neural networks is applied to this problem. It is shown that the new algorithm is well suited for online implementation and has excellent performance. Computational results via extensive simulations are provided to illustrate the effectiveness of the algorithm. A comparative evaluation wi...

A numerical solution for heave prediction is developed within the context theories for both saturated and unsaturated soil behaviors. Basically, lowering the potential level of compressing on a saturated layer will cause heaving due to water absorption. This water absorption is in an opposite way, similar to water dissipation as what happens during unloading in consolidation process. However, i...

We present the development and application of small buoy systems for wave energy harvesting (free-floating or slackly moored), to produce about 1 KW per unit at full scale. These systems are targeted for powering distributed marine surveillance and instrumentation networks, and should be simple in concept, easily deployable, storm resilient, and low maintenance. Our work involved design, experi...

The resulting motion in waves can be considered as a superposition of the motion of the body in still water and the forces on the restrained body. In this study the effect of added mass fluctuation on vertical vibration of TLP in the case of vibration in still water for both free and forced vibration subjected to axial load at the top of the leg is presented. This effect is more important when ...

Ride quality depends on a combination of vertical displacement (heave) and angular displacement (pitch). Road irregularities are the main factor affecting ride comfort. Suspension elements between the road wheels and the vehicle body generate vertical forces which excite both heave and pitch motions. An active controller design based on time-scale separation and an "input decoupling transformat...

To minimize body motions, floating marine structures are often designed with natural frequencies far away from the spectrum of ocean waves. Such design considerations led to a class of deep draft caisson vessels (DDCV or spars). Even so, large resonant responses may still be generated by excitation from nonlinear interactions of waves with body motions. Past experiments indicated that a DDCV ex...

This paper presents the characteristics of heave motion responses and hydrodynamic forces a horizontal floating circular cylinder during wave–current interaction. A two-dimensional numerical model based on CFD (Computational Fluid Dynamics) method for modeling wave flow is validated verified. The were calculated analyzed under conditions different k values (stiffness spring), amplitudes, submer...

The response control of a very large floating structure (VLFS) is crucial issue that affects the stability and safety structure. This paper presents vibration method for stabilizing motion multi-modular VLFS by using set stiffness-adjustable connectors. proposed connector consists cylindrical spring with an embedded actuator, making its stiffness adjustable. In case study, layout such connector...