A computationally efficient quasi-two-degree-of-freedom (Q2DOF) stochastic model and a stability analysis of barges in random seas are presented in this paper. Based on the deterministic 2DOF coupled Roll-Heave model with highdegree polynomial approximation of restoring forces and moments developed in Part I, an attempt is made to further reduce the DOF of the model for efficient stochastic sta...

This paper presents a practical scheme to control heave motion for hover and automatic landing of a Rotary-wing Unmanned Aerial Vehicle (RUAV) in the presence of strong horizontal gusts. A heave motion model is constructed for the purpose of capturing dynamic variations of thrust due to horizontal gusts. Through construction of an effective gust estimator, a feedback-feedforward controller is d...

Expansive soils are considered to be the one of the highly problematic soil. These soils undergo large volume change based on the amount of moisture content.. Because of this behaviour, lightly loaded civil engineering structures founded on the expansive soils gets severely damaged. There are several mitigating techniques available to counteract the problems posed by the expansive soils. In rec...

Characteristics of heave compensation systems used on a marine drilling platform or drill-ship are analyzed. An active heave compensation system with two lift cylinders is proposed by COMRA (China Ocean Mineral Resources & Association), which will be used in 1000-m depth ocean poly-metallic nodule pilot mining system. A corresponding virtual prototype of this system is developed. The parametric...

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...