Cardiovascular and Perceptual Responses to an Open Water Channel Swim: A Case Study

2010 ◽  
Vol 42 ◽  
pp. 639
Author(s):  
Jennifer M. Schumacher ◽  
Daniel A. Judelson ◽  
Lenny D. Wiersma
Keyword(s):  
Water Channel ◽  
Open Water

Boundaries Influence on the Flow Field Around an Oscillating Sphere

2013 ◽  
Author(s):  
Domenica Mirauda ◽  
Antonio Volpe Plantamura ◽  
Stefano Malavasi
Keyword(s):  
Free Surface ◽  
Flow Field ◽  
Boundary Conditions ◽  
Damping Ratio ◽  
Water Channel ◽  
Open Water ◽  
Free Surface Flows ◽  
The Body ◽  
Sphere Diameter ◽  
Oscillating Sphere

This work analyzes the effects of the interaction between an oscillating sphere and free surface flows through the reconstruction of the flow field around the body and the analysis of the displacements. The experiments were performed in an open water channel, where the sphere had three different boundary conditions in respect to the flow, defined as h* (the ratio between the distance of the sphere upper surface from the free surface and the sphere diameter). A quasi-symmetric condition at h* = 2, with the sphere equally distant from the free surface and the channel bottom, and two conditions of asymmetric bounded flow, one with the sphere located at a distance of 0.003m from the bottom at h* = 3.97 and the other with the sphere close to the free surface at h* = 0, were considered. The sphere was free to move in two directions, streamwise (x) and transverse to the flow (y), and was characterized by values of mass ratio, m* = 1.34 (ratio between the system mass and the displaced fluid mass), and damping ratio, ζ = 0.004. The comparison between the results of the analyzed boundary conditions has shown the strong influence of the free surface on the evolution of the vortex structures downstream the obstacle.

Comparison of Stopping Modes for Pod-Driven Ships by Simulation Based on Model Testing

2005 ◽  
Vol 219 (2) ◽  
pp. 47-64 ◽  
Author(s):  
M D Woodward ◽  
M Atlar ◽  
D Clarke
Keyword(s):  
Load Condition ◽  
Open Water ◽  
Water Model ◽  
Simulation Algorithm ◽  
Time Domain Simulation ◽  
Dynamic Effects ◽  
Study Results ◽  
Simulation Based ◽  
Fluid Damping

Conventionally, the stopping of a ship is achieved by direct reversal of propeller rotation. However, the introduction of azimuthing pods presents other options. The following study examines the various modes that may be employed to stop a pod-driven ship. A continuous function is derived describing the hydrodynamic forces on both the propeller and the pod body for any load condition and helm angle, including fluid damping and added mass effects. The proposed function is validated through comparison with comprehensive open water model tests. Next, a time domain simulation algorithm is proposed to examine the dynamic effects including the mass inertia on both the propeller shaft and slewing stock. Finally, a simulation study for the proposed stopping modes is performed using a known design as a case study. Results and discussion are presented.

Landsat thermal infrared to detect sub-canopy riparian flooding

2021 ◽  
Author(s):  
Emanuel Storey ◽  
Witold Krajewski ◽  
Efthymios Nikolopoulos
Keyword(s):  
Open Water ◽  
Thermal Infrared ◽  
Short Wave ◽  
Mapping Technique ◽  
Landsat 8 ◽  
Infrared Observations ◽  
Plant Canopies ◽  
Multi Temporal ◽  
Flood Detection

<p>Satellite based flood detection can enhance understanding of risk to humans and infrastructures, geomorphic processes, and ecological effects.  Such application of optical satellite imagery has been mostly limited to the detection of water exposed to sky, as plant canopies tend to obstruct water visibility in short electromagnetic wavelengths.  This case study evaluates the utility in multi-temporal thermal infrared observations from Landsat 8 as a basis for detecting sub-canopy fluvial inundation resulting in ambient temperature change.</p><p>We selected three flood events of 2016 and 2019 along sections of the Mississippi, Cedar, and Wapsipinicon Rivers located in Iowa, Minnesota, and Wisconsin, United States.  Classification of sub-canopy water involved logical, threshold-exceedance criteria to capture thermal decline within channel-adjacent vegetated zones.  Open water extent in the floods was mapped based on short-wave infrared thresholds determined parametrically from baseline (non-flooded) observations.  Map accuracy was evaluated using higher-resolution (0.5–5.0 m) synchronic optical imagery.</p><p>Results demonstrate improved ability to detect sub-canopy inundation when thermal infrared change is incorporated: sub-canopy flood class accuracy was comparable to that of open water in previous studies.  The multi-temporal open-water mapping technique yielded high accuracy as compared to similar studies.  This research highlights the utility of Landsat thermal infrared data for monitoring riparian inundation and for validating other remotely sensed and simulated flood maps.</p>

scholarly journals Modeling the Impacts of Urbanization and Open Water Surface on Heavy Convective Rainfall: A Case Study over the Emerging Xiong'an City, China

2019 ◽  
Vol 124 (16) ◽  
pp. 9078-9098 ◽  
Author(s):  
Yue Xing ◽  
Guangheng Ni ◽  
Long Yang ◽  
Yan Yang ◽  
Pei Xing ◽  
...  
Keyword(s):  
Water Surface ◽  
Open Water ◽  
Convective Rainfall

Pacing and Mood Changes While Crossing the Adriatic Sea From Italy to Albania: A Case Study

2015 ◽  
Vol 10 (4) ◽  
pp. 520-523 ◽  
Author(s):  
Giulia De Ioannon ◽  
Giuseppe Cibelli ◽  
Sergio Mignardi ◽  
Agnese Antonelli ◽  
Laura Capranica ◽  
...  
Keyword(s):  
Perceived Exertion ◽  
Adriatic Sea ◽  
Mood State ◽  
Open Water ◽  
Fold Increase ◽  
Rating Of Perceived Exertion ◽  
Anthropometric Parameters ◽  
Stroke Length ◽  
Pacing Strategy

Purpose:To evaluate the pacing strategy, rating of perceived exertion (RPE), and mood during a 78.1-km solo ultraendurance open-water swim.Methods:Before and after the event, anthropometric parameters, cortisol, and the profile of mood state (POMS) of 1 male athlete (age 48 y, height 172 cm, body mass 68 kg, body fat 7.2%, athletic achievement: Italian record holder of the Channel Swim) were ascertained. Every 3 h during the event, average swimming speed (SS), stroke rate, stroke length (SL), and RPE were recorded.Results:The athlete completed the event in 23:44 h:min. Compared with the first 3 h of swimming, decreases in SS (−33%) and SL (−25%) were observed between 18 h and 21 h. Thereafter, the athlete increased SS (+41%) and SL (+17%) between 21 h and the end. RPE steadily increased from the beginning to the last 6 h of swimming. Cortisol showed a 23-fold increase. After the event, POMS showed a 500% increase in fatigue, 44% decrease in tension, and 77% decrease in vigor.Conclusion:For the first time ever an athlete crossed the Adriatic Sea. This case study shows that the athlete adopted a variable pacing strategy to complete 78 km. Despite the athlete perceiving his effort at maximum during the last 6 h, the observed increases in SS at the end of the event might substantiate his high potential motivation to accomplish this challenging and unique event.

scholarly journals Modified Equation of Impulse for Solitons in an Open Water Channel

2021 ◽  
Vol 6 (1) ◽  
Author(s):  
A. N. Volobuev ◽  
Keyword(s):  
Solitary Wave ◽  
Continuity Equation ◽  
Water Channel ◽  
Open Water ◽  
Geometrical Characteristics ◽  
Correct Calculation ◽  
The Given ◽  
The Waves ◽  
Modified Equation ◽  
Impulse Equation

On the basis of the certain form of write of an impulse equation the modeling of the solitary waves in the water channel is examined at action of gravitation forces. It is shown that as against an existing method of modelling where the waves propagating from left to right turn out from the equation of an impulse, and from right to left from the continuity equation in the offered technique both waves turn out from the equation of impulse. It is marked that the given method is physically more correct. Calculation of a solitary wave, its velocity and geometrical characteristics is submitted.

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