Although homeostatic mechanisms remain of utmost importance, rhythmic changes are present also. The main ones have a period of 24 h (circadian) or about 2-3 h (ultradian). Circadian rhythms are derived from a body clock, found in the base of the brain, and from the pattern of our sleep-wake cycle, including activity and meal times. These rhythms promote the regular changes between an active wak...

A wake model for the free-streamline theory is proposed to treat the two-dimensional flow past an obstacle with a wake or cavity formation. In this model the wake flow is approximately described in the large by an equivalent potential flow such that along the wake boundary the pressure first assumes a prescribed constant under-pressure in a region downstream of the separation points (called the...

The classical wake oscillator model is capable of predicting the vortex-induced vibration response a cylinder at high mass-damping ratios, but it fails to perform satisfactorily low ratios. A modified presented in this paper. modification method involves analyzing variation law add mass coefficient versus reduced velocity and expressing reference lift CL0 as function coefficient. has been demon...

Although homeostatic mechanisms remain of utmost importance, rhythmic changes are present also. The main ones have a period of 24 h (circadian) or about 2-3 h (ultradian). Circadian rhythms are derived from a body clock, found in the base of the brain, and from the pattern of our sleep wake cycle, including activity and meal times. These rhythms promote the regular changes between an active wak...

All mammals have daily cycles of behavior (e.g., wake-sleep and feeding), and physiology (e.g., hormone secretion and body temperature). These cycles are typically entrained to the external light/dark cycle, but they can be altered dramatically under conditions of restricted food availability, changes in ambient temperature, or the presence of external stimuli such as predators. During the past...

Recent work in experimental neurophysiology has identified distinct neuronal populations in the rodent brain stem and hypothalamus that selectively promote wake and sleep. Mutual inhibition between these cell groups has suggested the conceptual model of a sleep-wake switch that controls transitions between wake and sleep while minimizing time spent in intermediate states. By combining wake- and...

The wind farm layout program FLaP (Farm Layout Program) estimates the wind speed at any point in a wind farm and the power output of the turbines. The ambient flow conditions and the properties of the turbines and the farm are used as input. The core of the program is an axis-symmetric wake model, describing the wake behind one rotor. Here an approach based on the simplified Reynolds equation w...

1 Model equations 2 1.1 A simple model of the two-switch negative feedback oscillator (Design I) . . . . . . . . . . . . . . . . . 2 1.1.1 Two-dimensional simple models . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 1.2 A simple model of the amplified negative feedback oscillator (Design II) . . . . . . . . . . . . . . . . . 7 1.3 A simple model of the three-switch ri...