A new algorithm for ship wake detection is developed with the aim of ship heading and velocity estimation. It exploits the Radon transform and utilizes merit indexes in the intensity domain to validate the detected linear features as real components of the ship wake. Finally, ship velocity is estimated by state-of-the-art techniques of azimuth shift and Kelvin arm wavelength. The algorithm is a...

An area-efficient 60-GHz wake-up receiver (WuRx) using reconfiguration techniques of multistage low-noise amplifiers (LNAs) is presented. The gain stages of the 60-GHz LNA are reused as the envelope detectors for the wake-up receiver. Therefore, the bulky components such as extra switches between the wake-up receiver and the LNA, additional antennas, and excess input matching network can be rem...

We searched the COBE DIRBE Sky and Zodi Atlas for a wake of dust trailing Mars and for Trojan dust near Jupiter’s L5 Lagrange point. We compare the DIRBE images to a model Mars wake based on the empirical model of the Earth’s wake as seen by the DIRBE and place a 3-σ upper limit on the fractional overdensity of particles in the Mars wake of 18% of the fractional overdensity trailing the Earth. ...

A highly accurate Fourier-Chebyshev spectral collocation method has been used to simulate flow in the wake of a sphere in the Reynolds number range from 350 to 650. Flow visualizations and frequency spectra provide a glimpse of the complex vortex dynamics that are observed in the sphere wake. It is found that in addition to the vortex shedding frequency which corresponds to the shedding of larg...

Sleep/wake disturbance is a feature of almost all common age-related neurodegenerative diseases. Although the reason for this is unknown, it is likely that this inability to maintain sleep and wake states is in large part due to declines in the number and function of wake-active neurons, populations of cells that fire only during waking and are silent during sleep. Consistent with this, many of...

Bio-inspired aerodynamic designs have been mutually promoted by the studies on flapping wings in the past decades. Among the tons of researches topics, the wake formation/structure of an oscillating airfoil is more attractive, and it results in the development of both numerical methods and flow diagnostics techniques. In this paper, wake formation behind a sinusoidally piching NACA 0012 has bee...

The unsteady wake of an EPPLER 361 airfoil in pitching motion has been investigated in a subsonic wind tunnel by hot-wire anemometry. The airfoil was given the pitching motion about the one-quarter chord axis at reduced frequency of 0182. Streamwise mean velocity profiles (wake profiles) were investigated at several vertically aligned points behind the airfoil at one-quarter chord downstream di...

The aim of this study was to examine the validity of activity-based monitoring (actigraphy) for the assessment of sleep-wake patterns during the 1st year of life. Forty-one infants were directly observed for sleep-wake state determination by trained observers. Concomitant activity data obtained by actigraphs attached to the infants’ ankles during the observation were matched on a minute-by-minu...

Individual pitch control (IPC) for wind turbine load reduction in Region 3 operation is improved when wake interaction is considered. The Larsen wake model is applied for composing the rotor wind profile for downstream turbines under wake interaction. The wind profile of the turbine wake was generated by modifying the NREL’s TurbSim codes. The state-space models of wind turbine were obtained vi...

A general free wake geometry calculation for wings and rotors is presented. The method, which has been implemented in CAMRAD II, gives good performance and airloads correlation at advance ratios of 0.05 and above, with reasonable computation speed. The wake geometry distortion can be calculated for multiple wings, multiple rotors, and non-identical blades; for all wake structures, including mul...