Estimation of blood velocities using ultrasound and time-domain cross-correlation is investigated. The measurement principle is introduced and the basic properties of the cross-correlation function is discussed. Expressions for the variance of the estimates of the peak location are given showing the innuence of integration time, transducer bandwidth and signal-to-noise ratio. It is also shown t...

different construction materials with different roughness used to make circular weirs highly affect surface roughness and, in turn, flow hydraulics passing over these structures.  in the present research, numerous experiments under different hydraulic conditions were performed on a physical model to study the effects of roughness on flow hydraulics over a circular weir. the flow hydraulics incl...

S U M M A R Y We use cross-correlation of seismic noise recorded at stations in the San Andreas Fault Observatory at Depth (SAFOD) pilot hole to extract P and S waves and measure S-wave anisotropy on the horizontal components. The data are recorded at seven three-component stations at depths from 1857 to 2097 m in the pilot hole. In late September and early 2004 October drilling noise underneat...

oily wastewaters from oil refineries and oil distribution centers are one of the most important environmental concerns in recent decades; therefore, it is critical to treat these types of wastewaters. in this study, the performance of different polyethersulfone hollow fiber membranes in oily wastewaters treatment was investigated and the effects of operating conditions such as transmembrane pre...

A PIV algorithm is presented for estimating time-averaged or phase-averaged velocity fields. The algorithm can be applied to situations where signal strength is not sufficient for standard cross correlation techniques, such as a low number of particle images in an interrogation spot, or poor image quality. The algorithm can also be used to increase the spatial resolution of measurements by allo...

The implementationof real-time blood velocity estimators using time-domain cross-correlation is investigated. The basic algorithm is presented for doing stationary echo canceling, cross-correlation estimation and subsequent velocity estimation. Sampled data acquired at rates of approximately 20 MHz are used in the algorithm imposing a heavy burden on the signal processing hardware. The algorith...

Recent experiments have demonstrated that dynein motor exhibits catch bonding behaviour, in which the unbinding rate of a single dynein decreases with increasing force, for a certain range of force. Motivated by these experiments, we propose a model for catch bonding in dynein using a threshold force bond deformation (TFBD) model wherein catch bonding sets in beyond a critical applied load forc...

Hydrogeological and Geochemical Characterization Both surface and crosshole tomographic geophysical data have been used in the saprolite and carbonate gravel (Areas 3 and 2, respectively) to delineate large scale geologic structure, nitrate plume boundaries, and localscale fracture zonation. Surface electri seismic data were originally used in a reconnaissance mode to choose the location for th...