The interdependency of biological and physical components of the arctic tundra system can yield strongly nonlinear processes with potential thresholds for ecosystem shifts. Hydrology critically infl uences the ecosystem dynamics in the Arctic, even though the tundra appears to have a relatively simple hydrologic system, often consisting of only a saturated active layer underlain by permafrost. ...

One of the most-studied unsteady locomotor behaviors exhibited by fishes is the c-start escape response. Although the kinematics of these responses have been studied extensively and two well-defined kinematic stages have been documented, only a few studies have focused on hydrodynamic patterns generated by fishes executing escape behaviors. Previous work has shown that escape responses by blueg...

Heave compensation systems are essential for operations’ safety, reliability, and efficiency in harsh offshore environments. This paper investigates the vibration suppression problem of a type deep-sea robot with length time variation operating environments active heave systems, where hydraulic compensators implement actuators input nonlinearity, model coupling, unknown nonlinear disturbances. ...

The DeepCwind floating wind turbine platform has become one of the most successful structures for accommercial farms, and stability it is crucial survivability. Hence, this paper studies an anti-oscillation device with purpose reducing heave surge effects platform. influence various chamfered perforations at different sizes anti-heave on was further studied by numerical experimental methods. Fu...

Abstract In this study, a three degrees of freedom nonlinear air cushion vehicle (ACV) model is introduced to examine the dynamic behavior heave and pitch responses in addition pressure ACV both time frequency domains. The based on compressible flow Bernoulli’s equation thermodynamics isentropic relations along with Newton second law translation rotation. dynamical investigation was numerical s...