Results 181 to 190 of about 84,280 (228)
Some of the next articles are maybe not open access.
Seedless Velocimetry Measurements by Schlieren Image Velocimetry
AIAA Journal, 2011Schlieren optical systems have been used to perform velocity measurements in refractive turbulent flows using particle image velocimetry algorithms. This schlieren image velocimetry (schlieren "particle image velocimetry") technique makes use of naturally occurring refractive turbulent eddies in a flow as virtual "seed particles" upon which velocimetry
Michael J. Hargather +3 more
openaire +1 more source
Doppler Velocimetry in Obstetrics
Obstetrics and Gynecology Clinics of North America, 1990Doppler ultrasound velocimetry offers a noninvasive method for assessing velocities in the various components of the fetal circulation including the cardiac, umbilical, cerebral, and aortic flows. As the volumetric flow measurement in these circumstances is prone to significant errors, the major approach has been to analyze the maximum frequency shift ...
D, Maulik, P, Yarlagadda, G, Downing
openaire +2 more sources
Applied Optics, 1988
A new technique, digital image velocimetry, is proposed for measurement of instantaneous velocity fields of time dependent flows. A time sequence of single-exposure images of seed particles are captured with a high speed camera, and the sampled images are then digitized on an image processor, enhanced, and superposed to construct a multiple-exposure ...
openaire +2 more sources
A new technique, digital image velocimetry, is proposed for measurement of instantaneous velocity fields of time dependent flows. A time sequence of single-exposure images of seed particles are captured with a high speed camera, and the sampled images are then digitized on an image processor, enhanced, and superposed to construct a multiple-exposure ...
openaire +2 more sources
Doppler velocimetry in pregnancy
Seminars in Ultrasound, CT and MRI, 1993Since the late 1970s, Doppler velocimetry has been investigated extensively for use in obstetrics. Initially, this technique showed promise for the management of certain complications of pregnancy; this promise has yet to be fulfilled. Doppler velocimetry of either the uterine or umbilical vessels, which showed some merit in selecting growth-retarded ...
openaire +2 more sources
Planar Doppler Velocimetry: Three-Component Velocimetry in Supersonic Jets
AIAA Journal, 1998A three-component planar Doppler velocimetry system was developed and used to make mean and instantaneous velocity measurements in a Mach 2 axisymmetric freejet. The mean measurements were in good agreement with reference laser Doppler velocimetry measurements taken in the same flowfield, whereas the instantaneous measurements were in fair agreement ...
Pamela Clancy +2 more
openaire +1 more source
Perceptual and Motor Skills, 1972
A velocimeter employing secondary emission photomultipliers has been described. A softball or other light colored object is detected against a black background under room ambient light conditions. The throwing field is triangular with a useable area of approximately 30 ft2.
openaire +2 more sources
A velocimeter employing secondary emission photomultipliers has been described. A softball or other light colored object is detected against a black background under room ambient light conditions. The throwing field is triangular with a useable area of approximately 30 ft2.
openaire +2 more sources
Ultrasonic Velocimetry of Biological Compounds
Annual Review of Biophysics and Biophysical Chemistry, 1991Ultrasonic velocimetry, a method of molecular biological studies developed in recent years, is an effective tool for investigating hydration of biological substances, conformational transitions of biopolymers and molecular interactions. The method is based upon precise measurements of ultrasonic velocity in solutions of biological substances. The paper
openaire +3 more sources
Ophthalmic Artery Velocimetry in Preeclampsia
Gynecologic and Obstetric Investigation, 1995Our objective was to compare ophthalmic artery pulsatility index values from normal pregnant women with those from preeclampsia patients. The ophthalmic artery of 20 normotensive pregnant women, 7 mildly preeclamptic and 2 severely preeclamptic patients was studied once with color Doppler flow imaging and pulsed Doppler ultrasonography after 32 weeks ...
T, Hata, D, Senoh, K, Hata, M, Kitao
openaire +2 more sources
[Velocimetry and sympathectomy].
Journal des maladies vasculaires, 1983In a previous work, the writers have described the influence of vasomotoricity on the shape of the ultrasonic velocimetric curves (Doppler). A vasodilatation induced by an anaesthesia of the sympathetic chain or by a general anaesthesia by penthotal produces a raising of the whole curve above the basic line. The writers have studied in the present work
J, van der Stricht, A, Bertrand
openaire +1 more source
Middle Cerebral Artery Velocimetry: Different Clinical Relevance Depending on Umbilical Velocimetry
Obstetrics & Gynecology, 1997To evaluate the role of cerebral velocimetry as a predictor of perinatal outcome in high-risk pregnancies.Middle cerebral artery pulsatility index was measured in 576 high-risk pregnancies undergoing umbilical velocimetry. The results of both tests were evaluated with respect to the birth of small for gestational age (SGA) infants and adverse perinatal
STRIGINI, FRANCESCA ANNA LETIZIA +5 more
openaire +3 more sources