Channel slope adjustment in reduced gravity environments and implications for Martian channels

Geology ◽  
2018 ◽  
Vol 46 (2) ◽  
pp. 183-186 ◽  
Author(s):  
Kory M. Konsoer ◽  
Jessica LeRoy ◽  
Devon Burr ◽  
Gary Parker ◽  
Robert Jacobsen ◽  
...  
Keyword(s):  
Reduced Gravity ◽  
Channel Slope ◽  
Slope Adjustment

Validation Test Report for OCEANS 1.0: The 1/40 Global, Reduced Gravity NRL Layered Ocean Model

1998 ◽  
Author(s):  
E. J. Metzger ◽  
Robert C. Rhodes ◽  
Dong S. Ko ◽  
Harley E. Hurlburt
Keyword(s):  
Ocean Model ◽  
Reduced Gravity ◽  
Test Report ◽  
Validation Test

scholarly journals Geomorphic effects of recurrent outburst superfloods in the Yigong River on the southeastern margin of Tibet

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Kaiheng Hu ◽  
Chaohua Wu ◽  
Li Wei ◽  
Xiaopeng Zhang ◽  
Qiyuan Zhang ◽  
...  
Keyword(s):  
Landslide Dam ◽  
Upstream Migration ◽  
One Dimensional ◽  
Landform Evolution ◽  
Outburst Floods ◽  
Stepwise Method ◽  
Large Landslide ◽  
Southeastern Margin ◽  
Channel Slope ◽  
The One

AbstractLandslide dam outburst floods have a significant impact on landform evolution in high mountainous areas. Historic landslide dams on the Yigong River, southeastern Tibet, generated two outburst superfloods > 105 m3/s in 1902 and 2000 AD. One of the slackwater deposits, which was newly found immediately downstream of the historic dams, has been dated to 7 ka BP. The one-dimensional backwater stepwise method gives an estimate of 225,000 m3/s for the peak flow related to the paleo-stage indicator of 7 ka BP. The recurrence of at least three large landslide dam impoundments and super-outburst floods at the exit of Yigong Lake during the Holocene greatly changed the morphology of the Yigong River. More than 0.26 billion m3 of sediment has been aggraded in the dammed lake while the landslide sediment doubles the channel slope behind the dam. Repeated landslide damming may be a persistent source of outburst floods and impede the upstream migration of river knickpoints in the southeastern margin of Tibet.

scholarly journals Modulation of spatial and temporal modules in lower limb muscle activations during walking with simulated reduced gravity

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Shota Hagio ◽  
Makoto Nakazato ◽  
Motoki Kouzaki
Keyword(s):  
Matrix Factorization ◽  
Lower Limb ◽  
Nonnegative Matrix Factorization ◽  
Walking Speed ◽  
Nonnegative Matrix ◽  
Tensor Decomposition ◽  
Reduced Gravity ◽  
Dependent Variables ◽  
Specific Speed ◽  
Muscle Activations

AbstractGravity plays a crucial role in shaping patterned locomotor output to maintain dynamic stability during locomotion. The present study aimed to clarify the gravity-dependent regulation of modules that organize multiple muscle activities during walking in humans. Participants walked on a treadmill at seven speeds (1–6 km h−1 and a subject- and gravity-specific speed determined by the Froude number (Fr) corresponding to 0.25) while their body weight was partially supported by a lift to simulate walking with five levels of gravity conditions from 0.07 to 1 g. Modules, i.e., muscle-weighting vectors (spatial modules) and phase-dependent activation coefficients (temporal modules), were extracted from 12 lower-limb electromyographic (EMG) activities in each gravity (Fr ~ 0.25) using nonnegative matrix factorization. Additionally, a tensor decomposition model was fit to the EMG data to quantify variables depending on the gravity conditions and walking speed with prescribed spatial and temporal modules. The results demonstrated that muscle activity could be explained by four modules from 1 to 0.16 g and three modules at 0.07 g, and the modules were shared for both spatial and temporal components among the gravity conditions. The task-dependent variables of the modules acting on the supporting phase linearly decreased with decreasing gravity, whereas that of the module contributing to activation prior to foot contact showed nonlinear U-shaped modulation. Moreover, the profiles of the gravity-dependent modulation changed as a function of walking speed. In conclusion, reduced gravity walking was achieved by regulating the contribution of prescribed spatial and temporal coordination in muscle activities.

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