Results 261 to 270 of about 771,464 (302)

Accurate Velocity Measurement With a Narrowband Doppler Current Profiler

1993
Abstract : Accurate velocity of an ocean going vessel with respect to the water can be determined in real time by utilizing a Doppler Current Profiler (DCP) system. The DCP employs multiple sonar beams with a plurality of bins or returns from various depth segments.
Blair H. Brumley, Peter T. Shaw
openaire   +1 more source

River Habitat Quality from River Velocities Measured Using Acoustic Doppler Current Profiler

Environmental Management, 2005
Prior research has demonstrated the utility of metrics based on spatial velocity gradients to characterize and describe stream habitat, with higher gradients generally indicative of higher levels of physical heterogeneity and thus habitat quality. However, detailed velocity data needed to compute these metrics are difficult to obtain.
F Douglas, Shields, J R, Rigby
openaire   +2 more sources

Velocity Measurements in the Deep Western Boundary Current of the South Pacific

Nature, 1970
IN their schematic theory of the deep ocean circulation, Stommel and Arons1 require deep western boundary currents in each of the world's oceans as the means by which cold deep water is transported from polar regions to middle and low latitudes. These have been measured directly in the North Atlantic2, inferred from the density field and property ...
B A, Warren, A D, Voorhis
openaire   +2 more sources

Research for measuring velocity and direction of current from dynamic image

The 6th International Conference on Soft Computing and Intelligent Systems, and The 13th International Symposium on Advanced Intelligence Systems, 2012
The speed and direction of coastal ocean surface currents are very important elements in examining land reclamation or establishment of coastal levees. Measuring the speed of sea surface currents generally employs a radar system using Doppler effect. However, there is a problem that it is unable to measure the current in a wide area because the system ...
Yuki Fukushima, Etsuji Kitagawa, Hirokazu Muraki, Takehiro Kashiyama, Shigenori Tanaka   +4 more
openaire   +1 more source

Adaptive Control of Electrically-Driven Robot Manipulators Without Velocity/Current Measurements

Volume 4A: Dynamics, Vibration, and Control, 2014
An adaptive output feedback controller for electrically-driven robot manipulators is developed in this paper. The proposed controller can compensate for parametric uncertainties while only requiring link position measurements. To eliminate the need for measuring link velocity and electrical winding current, two individual observers are used as a ...
Mohamadreza Homayounzade, Mehdi Keshmiri, Mohammad Keshmiri   +2 more
openaire   +1 more source

Measurement of Bed Load Velocity using an Acoustic Doppler Current Profiler

Journal of Hydraulic Engineering, 2002
A new technique has been developed to measure the apparent velocity of bed load (\Iυ\da\N) using an acoustic Doppler current profiler. The technique involves estimating the bias in bottom tracking due to a moving bottom. Mean \Iυ\da\N measured at sampling stations in the gravel-bed Fraser River correlated well (\Ir²\N=0.93, \in=9) with mean bed load ...
Colin D. Rennie, Robert G. Millar, Michael A. Church   +2 more
openaire   +1 more source

Use of Bagnold's velocity meter in laboratory density current measurements

Journal of Scientific Instruments, 1967
A modified version of Bagnold's velocity meter, suitable for determining the mean velocity at a point in a salt water laboratory density current, is described. The dynamic head detected by a small bore Pitot nozzle is balanced by the dynamic head of an opposing jet of fresh water.
openaire   +1 more source

Synchronous Lagrangian and Eulerian velocity measurements. IEEE Sixth Working Conference on Current Measurement

Proceedings of the IEEE Sixth Working Conference on Current Measurement (Cat. No.99CH36331), 1999
A Phased Array Doppler Sonar (PADS), as developed at SIO, images both acoustic backscatter intensity and Doppler shift over areas up to 90 degrees in bearing by 500 m in range. Sequences of are recorded continuously for up to two months, with individual "pings" 0.5 to 1.0 seconds apart.
openaire   +1 more source

Comments on "Current velocity measurements using acoustic doppler backscatter: A Review"

IEEE Journal of Oceanic Engineering, 1987
Omissions in the subject paper, especially lack of reference to one 1968 paper by the author of this letter, may tend to mislead the reader. The subject paper was perhaps too brief to clear the record.
W. Vlasak, W. Woodward, G. Appell
openaire   +1 more source

Using a lowered acoustic Doppler current profiler for measuring current velocities in the Black Sea

Oceanology, 2007
The results obtained with the use of a lowered acoustic Doppler current profiler (LADCP) are presented. The use of the LADCP from a vessel was the first in the history of the study of the Black Sea. The measurements were carried out in the northeastern Black Sea under the auspices of the Black Sea Ecosystem Recovery Program (BSERP) in May 2004.
D. D. Aleinik, G. I. Shapiro, L. D. Mee, E. M. Lemeshko   +3 more
openaire   +1 more source