in this paper, a nonlinear model of the underactuated six degrees of freedom (6 dof) quadrotor helicopter was derived based on the newton-euler formalism. a new nonlinear robust control strategy was proposed to solve the stabilizing and path following problems in presence of external disturbances and parametric uncertainties. the proposed control structure consist of a sliding mode control base...

abstract background: the prevalence of disordered eating behaviors has been reported to increase in recent decades; therefore, the search for specific psychological variables that may contribute to the etiology of this disorder is of great importance. the current study examined the mediating role of the emotion regulation difficulties on the relationship between body image disturbance and disor...

Infancy is a critical developmental period involving establishment of the neurological underpinnings of psychological, affective and relational functioning. The integration of findings from developmental and attachment theories and neurodevelopment has contributed to greater understanding of the significance of early relationships and the developmental impact of interactional disturbance. This ...

It is widely agreed that overtraining should be employed in order to achieve peak performance but it is also recognised that overtraining can actually produce decrements in performance. The challenge appears to be one of monitoring stress indicators in the athlete in order to titrate the training stimulus and prevent the onset of staleness. The present paper summarises a ten-year research effor...

Epidemic transmission is one of the critical density-dependent mechanisms that affect species viability and dynamics. In a predator-prey system, epidemic transmission can strongly affect the success probability of hunting, especially for social animals. Predators, therefore, will suffer from the positive density-dependence, i.e., Allee effect, due to epidemic transmission in the population. The...

Wind disturbance can create large forest blowdowns, which greatly reduces live biomass and adds uncertainty to the strength of the Amazon carbon sink. Observational studies from within the central Amazon have quantified blowdown size and estimated total mortality but have not determined which trees are most likely to die from a catastrophic wind disturbance. Also, the impact of spatial dependen...

This study compares the rate and perceptions of interruptions experienced by practice nurses and GPs. During two recording periods, nurses noted the number of interruptions they experienced before and during their consultations (Paxton et al 1996). The nurses reported 48.5 interruptions per 100 consultations in the first period and 30.2 in the second. Fifty per cent of nurses in the first perio...

A description is given of a practical clinical test of contrast sensitivity and of the results obtained on a normal population. An account is given of recent physiological work which illustrates the potential usefulness of the method in ophthalmology, and the clinical results obtained by the author and others are summarised.