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total: 380
Search results for: CRITICAL VELOCITY
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Wavelet transform analysis to assess oscillations in pial artery pulsation at the human cardiac frequency
PublicationPial artery adjustments to changes in blood pressure (BP)may last only seconds in humans. Using a novelmethod called near-infrared transillumination backscattering sounding (NIR-T/BSS) that allows for the non-invasive measurement of pial artery pulsation (cc-TQ) in humans, we aimed to assess the relationship between spontaneous oscillations in BP and cc-TQ at frequencies between 0.5 Hz and 5 Hz. We hypothesized that analysis of...
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Suspended-sediment transport related to ice-cover conditions during cold and warm winters, Toudaoguai stretch of the Yellow River, Inner Mongolia, China
PublicationThe presence of winter ice in cold regions changes the water level, flow rate, velocity distribution, and other parameters of the river, which in turn affects the sediment concentration and channel evolution. Based on data obtained from Toudaoguai Hydrological Station from 1959 to 2021, this study examines the characteristics of the ice regime during cold and warm winters and the water and sediment transport processes along the...
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UUV and AUV Vehicles as the autonomous systems for naval applications
PublicationThere is a growing pressure to investigate how to design and build the unmanned underwater vehicles of different types which are devoted towards performing many tasks under the water surface according to the data missions. During the recent years the Department of Ship Design and Subsea Robotics, Faculty of Ocean Engineering and Ship Technology, Gdansk University of Technology designed and built a few types of unmanned underwater...
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Petrophysical analyses of rock construction materials from the Roman rural settlement in Podšilo bay on Rab island (NE Adriatic, Croatia)
PublicationThis article presents the results of petrophysical analyses of limestones and sandstones used for the construction of the wall structures of a Roman rural settlement located in Podšilo Bay on Rab Island (Croatia). An on-site analysis of the walls indicated the use of different lithotypes, which is an uncommon case in the area. So far, no petrophysical properties of the applied materials have been tested, and their provenance...
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Dew and hoarfrost frequency, formation efficiency and chemistry in Wroclaw, Poland
PublicationThis article presents the results of a research study concerning a comparison of frequency, formation efficiency and basic physico-chemical properties of dew and hoarfrost in urban conditions. Longer than two-year series of measurements was carried out from 1 February 2008 to 10 March 2010 in Wroclaw, Poland. Sampling of atmospheric deposits was made by means of insulated plain passive radiative condensers, which allowed to collect...
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Peptide Permeases in Candida albicans
PublicationAims: The aim of this work was to characterize oligopeptide uptake in Candida albicans mutants in which the genes encoding putative peptide permeases were selectively disrupted. Initial velocities of transport of model oligopeptides, (Ala)2, (Ala)3, (Ala)4, and sensitivity of mutants to antifungal oligopeptides containing N3-(4-methoxyfumaroyl)-L-2,3-diaminopropanoic acid (FMDP) were determined and compared to those of the wild-type...
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TIME- AND FREQUENCY-DOMAIN QUASI-2D SMALL-SIGNAL MOSFET MODELS
PublicationA novel approach to small-signal MOSFET modeling is presented in this book. As a result, time- and frequency-domain physics-based quasi-2D NQS four-terminal small-signal MOSFET models are proposed. The time-domain model provides the background to a novel DIBL-included quasi‑2D NQS four-terminal frequency-domain small-signal MOSFET model. Parameters and electrical quantities of the frequency-domain model are described by explicit...
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Electrohydrodynamic Flow Patterns in a Narrow Electrostatic Precipitator with Longitudinal Wire Electrode for Various Electrode Geometries
PublicationRecently narrow electrostatic precipitators (ESPs) have become a subject of interest because of their possible application in diesel engines. In this paper results of 2-dimensional (2D) Particle Image Velocimetry (PIV) measurements of the flow patterns in a narrow ESP for a various electrode geometries are presented. The PIV measurements were carried out in the observation plane that is perpendicular to the ESP duct. The ESP was...
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Non-Newtonian Mathematics Instead of Non-Newtonian Physics: Dark Matter and Dark Energy from a Mismatch of Arithmetics
PublicationNewtonian physics is based on Newtonian calculus applied to Newtonian dynamics. New paradigms such as ‘modified Newtonian dynamics’ (MOND) change the dynamics, but do not alter the calculus. However, calculus is dependent on arithmetic, that is the ways we add and multiply numbers. For example, in special relativity we add and subtract velocities by means of addition β1⊕β2=tanh(tanh−1(β1)+tanh−1(β2)), although multiplication β1⊙β2=tanh(tanh−1(β1)⋅tanh−1(β2)),...
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Sympathetic Activation Does Not Affect the Cardiac and Respiratory Contribution to the Relationship between Blood Pressure and Pial Artery Pulsation Oscillations in Healthy Subjects
PublicationUsing a novel method called near-infrared transillumination backscattering sounding (NIR-T/BSS) that allows for the non-invasive measurement of pial artery pulsation (cc-TQ) and subarachnoid width (sas-TQ) in humans, we assessed the influence of sympathetic activation on the cardiac and respiratory contribution to blood pressure (BP) cc-TQ oscillations in healthy subjects. The pial artery and subarachnoid width response to handgrip...