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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

The value of extracranial arterial blood flow volume in ischaemic cerebrovascular disease. / CUHK electronic theses & dissertations collection

January 2002 (has links)
Ho Sin Yee, Stella. / "August 2002." / Thesis (Ph.D.)--Chinese University of Hong Kong, 2002. / Includes bibliographical references (p. 167-193). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Mode of access: World Wide Web. / Abstracts in English and Chinese.
12

Doppler ultrasound detection of tissue motion and flow generated by external energy /

Shi, Xuegong. January 2000 (has links)
Thesis (Ph. D.)--University of Washington, 2000. / Vita. Includes bibliographical references (leaves 161-175).
13

Effects of edge safety factor on the toroidal flow velocity of the STOR-M plasma.

2015 February 1900 (has links)
The effect of changing edge safety factor on the toroidal flow of the STOR-M plasma has been investigated during the application of both resonant magnetic perturbation (RMP) and compact torus injection (CTI). The edge safety factor was varied by varying the plasma current while keeping the toroidal field constant. A Czyner-Turner spectrometer was used to collect the spectral data from which the velocity of specific impurity ions was diagnosed. Time resolved velocity measurements were inferred from the Doppler wavelength shift of the emission lines. Impurity emission lines at different ionization stages are located at different radial locations within the STOR-M plasma. Properties of these impurity ions are assumed to be closely related the hydrogen ion (main working gas) due to the strong interaction among the ion species. Changing the edge safety factor has a similar effect on the toroidal flow of STOR-M plasma during discharges with both RMP and CTI. A velocity shear was discovered for different impurity ions. The toroidal flow is enhanced for edge ions while a reversal of flow is observed for core ions. As the edge safety factor reduces, the emission location for the core ions is located with q=2 surface and RMP has a significant impact on their toroidal flow velocity. It was also observed that CT injection has a significant effect on the toroidal velocity of the core ions compared to that of the edge ions. In addition, high plasma current (low safety factor) induced large change in the toroidal flow velocity of the STOR-M plasma.
14

On the autonomic control of blood flow and secretion in salivary glands : functional and morphological aspects of muscarinic receptor subtypes in different species /

Ryberg, Anders T., January 2007 (has links)
Diss. (sammanfattning) Göteborg : Göteborgs universitet, 2007. / Härtill 4 uppsatser.
15

Characterizing erythrocyte motions in flowing blood

Leggas, Markos, January 1999 (has links) (PDF)
Thesis (M.S. )--University of Tennessee Health Science Center, 1999 / Title from title page screen (viewed on July 16, 2008). Research advisor: Eugene C. Eckstein. Document formatted into pages (91 p. : ill.). Vita. Abstract. Includes bibliographical references (p. 73-77).
16

Control of blood flow by the metabolic level in the exocrine pancreas

Beijer, Hendrikus Johannes Maria, January 1983 (has links)
Thesis (doctoral)--Rijksuniversiteit te Utrecht.
17

Μέτρηση ταχυτήτων ροής με αναρτημένη σφαίρα

Κουλουράς, Αθανάσιος 07 October 2011 (has links)
Στην παρούσα διατριβή γίνεται διερεύνηση της ικανότητας υπολογισμού της τοπικής ταχύτητας ροής με την χρήση εκκρεμούς, βυθισμένο εντός της ροής. / In this thesis is examined if the local flow velocity can be calculated by a pendulum, with a narrow margin of error.
18

The relationship between the blood flow and the marrow cavity pressure of bone

Hawk, Hubert Edmund January 1971 (has links)
An experimental animal model was developed to study and define the relationship between the blood flow and the marrow cavity pressure of bone. The study was carried out in 24 rabbits and 32 dogs under nembutol anesthesia. A multichannel physiograph was used to record simultaneously the systemic blood pressure, bone blood flow, marrow cavity pressure of bone and time sequence. The systemic blood pressure was measured by cannulating a brachial or carotid artery. The bone blood flow was measured by cannulating the nutrient vein and/or the nutrient artery. The marrow cavity pressure was measured by inserting a steel cannula through a drill hole in the cortex into the marrow cavity. The bones studied were mainly the tibia and femur. During the normal control condition, the marrow cavity pressure was found to have a wide range from animal to animal. In the rabbits, the range was from 20 to 60 mm. Hg. (15 to 50 percent of the systemic blood pressure). In the dogs, it ranged from 40 to 120 mm. Hg. (20 to 90 percent of the systemic blood pressure). However, the systemic blood pressure, intramedullary pressure and nutrient venous outflow were remarkably constant in a control period, therefore, their changes under experimental conditions were readily recordable. Various factors affecting bone circulation were studied. If the femoral vein is occluded the marrow cavity pressure rises and the nutrient venous outflow increases indicating venous congestion of bone. Nutrient artery occlusion causes a sharp fall in marrow cavity pressure coupled with a marked decrease in the nutrient venous outflow. Adrenalin and noradrenalin intravenous infusions produce a fall in marrow cavity pressure coupled with a decreased bone blood flow, despite an elevation in the systemic blood pressure. Isoproterenol hydrochloride generally causes a fall in the systemic blood pressure, widening of the pulse pressure, a fall in the marrow cavity pressure and a decrease in the nutrient venous outflow. Electrical sympathetic stimulation produces a fall in the marrow cavity pressure and a decrease in bone blood flow. Lumbar sympathectomy causes a rise in the marrow cavity pressure and an increase in the bone blood flow. Skeletal muscle contraction produces bone venous congestion with elevation of the marrow cavity pressure and increased nutrient venous outflow. Muscular relaxation causes a momentary sharp fall in the marrow cavity pressure to sub control levels before returning to the normal pressure. It is concluded that the marrow cavity pressure is bone blood flow dependent and reflects well the changes in the hemodynamics of bone. The narrow pressure rises if the arterial blood supply to bone increases or the venous congestion occurs in bone. The marrow pressure falls if the arterial blood supply to bone decreases or the venous drainage of bone is facilitated. / Surgery, Department of / Medicine, Faculty of / Graduate
19

A system for the acquisition and digital analysis of lower limb flow waveforms

Smith, Leonard January 1994 (has links)
A PC based waveform acquisition and analysis system has been developed for use in aorta-iliac arterial assessment. A Motorola DSP56001 based system containing dual Analog to Digital converters is used to sample phase quadrature demodulated signals from a commercially available continuous wave Doppler unit. The Power Spectral Density is calculated using an autoregressive model from which the mean velocity waveform is calculated. This waveform is used to calculate the damping factor, vessel compliance and runoff resistance of a simple electrical model of the lower limb arterial circulation using a non-linear regression technique of curve fitting in the time domain. A pilot study using the system shows a significant separation (p < 0.001 Mann Whitney U-test) between the damping factors of a normal control group (quartile range = 0. 15 - 0.25 ; median = 0. 19) and a patient group with angiographically determined aorta-iliac arterial disease (quartile range = 0.45 - 0.89 ; median= 0.49).
20

Submerged flexible vegetation impact on open channel flow velocity distribution: An analytical modelling study on drag and friction

Pu, Jaan H., Hussain, Awesar, Guo, Yakun, Vardakastanis, Nikolaos, Hanmaiahgari, P.R., Lam, Dennis 06 June 2019 (has links)
Yes / In this paper, an analytical model that represents the streamwise velocity distribution for open channel flow with submerged flexible vegetation is studied. In the present vegetated flow modelling, the whole flow field has been separated into two layers vertically: a vegetated layer and a non-vegetated free-water layer. Within the vegetated layer, an analysis of the mechanisms affecting water flow through flexible vegetation has been conducted. In the non-vegetated layer, a modified log-law equation that represents the velocity profile varying with vegetation height has been investigated. Based on the studied analytical model, a sensitivity analysis has been conducted to assess the influences of the drag and friction coefficients on the flow velocity. The investigated ranges of drag and friction coefficients have also been compared to published values. The findings suggest that the drag and friction coefficient values are non-constant at different depths and vegetation densities, unlike the constant values commonly suggested in literature. This phenomenon is particularly clear for flows with flexible vegetation, which is characterised by large deflection.

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