Meander migration and the lateral tilting of floodplains

2001 ◽  
Vol 37 (5) ◽  
pp. 1485-1502 ◽  
Author(s):  
Tao Sun ◽  
Paul Meakin ◽  
Torstein Jøssang
Keyword(s):  
Lateral Tilting ◽  
Meander Migration

Upstream and downstream morphodynamic influence in simulated and real meandering rivers

2021 ◽  
Author(s):  
Hossein amini ◽  
Guido Zolezzi ◽  
Federico Monegaglia ◽  
Emanuele Olivetti ◽  
Marco Tubino
Keyword(s):  
Migration Rate ◽  
Machine Learning Techniques ◽  
Stochastic Gradient Descent ◽  
Support Vector ◽  
Lateral Migration ◽  
Remotely Sensed Data ◽  
Meandering Rivers ◽  
Meandering River ◽  
Migration Rates ◽  
Meander Migration

<p>This study investigates the dependency of meander lateral migration rates on the spatial distribution of channel centerline curvature in both synthetic and real meandering rivers. It employs Machine Learning techniques (hereafter ML) to relate observed local lateral meander migration rates with the local and the upstream/downstream values of the centerline curvature. To achieve this goal, it was primarily essential to identify the feasibility of using ML in the meandering river's morphodynamics. We then determined the ability of ML to predict the excess near bank velocity based a set of input data using different regression techniques (linear and polynomial, Stochastic Gradient Descent, Multi-Layer Perceptron, and Support Vector Machine). We then moved forward to study the upstream-downstream influence on local migration rate. Synthetic meandering river planforms, as obtained through the planform evolution model of Bogoni et al. (2017), which is based on Zolezzi and Seminara (2001) meander flow model, were used as test cases for the calibration and check of the different adopted ML algorithms. The calibrated algorithms were then applied to multi-temporal information on meander planform dynamics obtained through the PyRiS software (Monegaglia et al., 2018), to quantify to which extent the upstream and downstream distribution of meander centerline curvature affects the local meander migration rate in real rivers.</p><p>References </p><p>1- Zolezzi, G., & Seminara, G. (2001b). Downstream and upstream influence in river meandering. Part 1. General theory and application overdeepening. Journal of Fluid Mechanics, 438(September 2015), 183–211. https://doi.org/10.1017/S002211200100427X</p><p>2- Monegaglia, F., Zolezzi, G., Güneralp, I., Henshaw, A. J., & Tubino, M. (2018). Automated extraction of meandering river morphodynamics from multitemporal remotely sensed data. In Environmental Modelling & Software (Vol. 105, pp. 171–186). https://doi.org/10.1016/j.envsoft.2018.03.028</p><p>3- Bogoni, M., Putti, M., & Lanzoni, S. (2017). Modeling meander morphodynamics over self-formed heterogeneous floodplains. In Water Resources Research (Vol. 53, Issue 6, pp. 5137–5157). https://doi.org/10.1002/2017wr020726</p><p>4- Benozzo, D.,  Olivetti, E., Avesani, P. (2017). Supervised Estimation of Granger-Based Causality between Time series. In Frontiers in Neuroinformatics. </p><p>https://doi.org/10.3389/fninf.2017.00068 </p><p>5- Sharma A., Kiciman, E. (2020). DoWhy: An End-to-End library for Causal Inference. arXiv preprint arXiv:2011.04216. </p><p>https://arxiv.org/abs/2011.04216</p>

Modelling of meander migration in an incised channel

2014 ◽  
Vol 29 (4) ◽  
pp. 441-453 ◽  
Author(s):  
Jianchun HUANG ◽  
Blair P. GREIMANN ◽  
Timothy J. RANDLE
Keyword(s):  
Incised Channel ◽  
Meander Migration

scholarly journals Quantifying Process-Based Mitigation Strategies in Historical Context: Separating Multiple Cumulative Effects on River Meander Migration

PLoS ONE ◽  
2014 ◽  
Vol 9 (6) ◽  
pp. e99736 ◽  
Author(s):  
Alexander K. Fremier ◽  
Evan H. Girvetz ◽  
Steven E. Greco ◽  
Eric W. Larsen
Keyword(s):  
Historical Context ◽  
Mitigation Strategies ◽  
Cumulative Effects ◽  
Meander Migration

Net local removal of floodplain sediment by river meander migration

Geomorphology ◽  
2008 ◽  
Vol 96 (1-2) ◽  
pp. 123-149 ◽  
Author(s):  
J. Wesley Lauer ◽  
Gary Parker
Keyword(s):  
Floodplain Sediment ◽  
Meander Migration

Modulation of soleus H reflex by lateral tilting in man

1992 ◽  
Vol 15 (4) ◽  
pp. 479-481 ◽  
Author(s):  
I. Aiello ◽  
G. Rosati ◽  
G. F. Sau ◽  
R. Cacciotto ◽  
M. E. Lentinu ◽  
...  
Keyword(s):  
H Reflex ◽  
Lateral Tilting

scholarly journals Cardiovascular responses during submaximal cycling with and without left-lateral tilting: insights for practical applications of stress echocardiography

2020 ◽  
pp. 1-4
Author(s):  
Alexander J. Beaumont ◽  
Laura J. Forrest ◽  
Viswanath Unnithan ◽  
Nicholas Sculthorpe
Keyword(s):  
Oxygen Uptake ◽  
Stress Echocardiography ◽  
Physiological Responses ◽  
Cardiovascular Responses ◽  
Heart Rates ◽  
Practical Applications ◽  
Lateral Tilt ◽  
Cardiorespiratory Responses ◽  
Fixed Power ◽  
Lateral Tilting

We investigated the cardiorespiratory responses to semi-supine exercise with (SS+45°) and without (SS-0°) a left-lateral tilt in 15 adults at fixed power output (70 W) and matched heart rates. At 70 W, oxygen uptake and heart rate reduced from upright to SS-0° then increased to SS+45° (p < 0.05). At matched heart rates, oxygen uptake and efficiency were lowest in SS+45° (p < 0.05). Left-lateral tilting should not be performed under the assumption that each position replicates the same cardiorespiratory responses. Novelty: Cardiorespiratory responses to exercise are influenced by left-lateral tilting, which should not be performed under the assumption that physiological responses are replicated between left-lateral positions.

Hiding responses of locusts to approaching objects

1999 ◽  
Vol 202 (12) ◽  
pp. 1701-1710 ◽  
Author(s):  
B. Hassenstein ◽  
R. Hustert
Keyword(s):  
Visual Angle ◽  
Predator Avoidance ◽  
Locusta Migratoria ◽  
Positional Information ◽  
Small Field ◽  
Response Latencies ◽  
Specific Goal ◽  
Angular Velocities ◽  
Plant Stem ◽  
Lateral Tilting

Locusts, Locusta migratoria, sitting on a plant stem hide from dark moving or expanding shapes in their environment. The fore- and middle legs perform this avoidance response by making lateral tilting movements, while the hindlegs slide laterally and guide rotation of the posterior body over the stem. During larger turns, the legs take lateral steps when lateral tilting is limited by the joints. Slow hiding movements of less than 300 degrees s-1 of angular velocity are induced by slowly changing (looming) shapes, and interposed stops or slowing of the movement can delay the progress of this hiding manoeuvre. Fast hiding movements with angular velocities between 120 degrees s-1 and 860 degrees s-1 proceed continuously and rapidly in response to rapidly expanding stimuli. Hiding responses to expanding shapes occur only after the expanding image has exceeded a threshold visual angle of 8–9.5 degrees. Hiding response latencies range between 220 ms and 1.2 s for fast hiding and are approximately 1.2 s for most slow hiding responses. Predator-avoidance responses such as freezing, jerking, crouching, walking backwards, dropping or jumping can be used instead of or in conjunction with hiding behaviour. We conclude that the fast hiding behaviour of locusts is a specific goal-directed type of optomotor behaviour requiring positional information from small-field detectors of shape expansion in the interneurone layers of the locust eye.

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