scholarly journals Targets, ripples and spirals in a precipitation system with anomalous dispersion

2015 ◽  
Vol 17 (30) ◽  
pp. 19806-19814 ◽  
Author(s):  
Mahmoud M. Ayass ◽  
Istvan Lagzi ◽  
Mazen Al-Ghoul
Keyword(s):  
Anomalous Diffusion ◽  
Heterogeneous System ◽  
Three Dimensional ◽  
Anomalous Dispersion ◽  
Precipitation System ◽  
Wave Phenomena ◽  
Dimensional Wave

We report multiple three-dimensional wave phenomena in a heterogeneous system due to anomalous diffusion.

scholarly journals Collaborative Pursuit-Evasion Strategy of UAV/UGV Heterogeneous System in Complex Three-Dimensional Polygonal Environment

Complexity ◽  
2020 ◽  
Vol 2020 ◽  
pp. 1-13
Author(s):  
Xiao Liang ◽  
Honglun Wang ◽  
Haitao Luo
Keyword(s):  
Visual Field ◽  
Heterogeneous System ◽  
Three Dimensional ◽  
Unmanned Ground Vehicle ◽  
Worst Case ◽  
Ground Vehicle ◽  
Pursuit Evasion ◽  
Evasion Game ◽  
Evasion Strategy ◽  
Aerial Vehicle

The UAV/UGV heterogeneous system combines the air superiority of UAV (unmanned aerial vehicle) and the ground superiority of UGV (unmanned ground vehicle). The system can complete a series of complex tasks and one of them is pursuit-evasion decision, so a collaborative strategy of UAV/UGV heterogeneous system is proposed to derive a pursuit-evasion game in complex three-dimensional (3D) polygonal environment, which is large enough but with boundary. Firstly, the system and task hypothesis are introduced. Then, an improved boundary value problem (BVP) is used to unify the terrain data of decision and path planning. Under the condition that the evader knows the position of collaborative pursuers at any time but pursuers just have a line-of-sight view, a worst case is analyzed and the strategy between the evader and pursuers is studied. According to the state of evader, the strategy of collaborative pursuers is discussed in three situations: evader is in the visual field of pursuers, evader just disappears from the visual field of pursuers, and the position of evader is completely unknown to pursuers. The simulation results show that the strategy does not guarantee that the pursuers will win the game in complex 3D polygonal environment, but it is optimal in the worst case.

scholarly journals Numerical simulation of the three-dimensional wave-induced currents on unstructured grid

2017 ◽  
Vol 31 (5) ◽  
pp. 539-548
Author(s):  
Ping Wang ◽  
Ning-chuan Zhang ◽  
Shuai Yuan ◽  
Wei-bin Chen
Keyword(s):  
Numerical Simulation ◽  
Unstructured Grid ◽  
Three Dimensional ◽  
Induced Currents ◽  
Wave Induced ◽  
Dimensional Wave

scholarly journals Symmetric Boundary Condition for Laplacian on Net of Regular Hexagons

2017 ◽  
Vol 9 (3) ◽  
pp. 46
Author(s):  
Daniel Lee
Keyword(s):  
Boundary Condition ◽  
Matrix Theory ◽  
Three Dimensional ◽  
Cardiac Tissues ◽  
Energy Product ◽  
Symmetric Boundary Condition ◽  
Almost All ◽  
Wave Phenomena ◽  
Dimensional Cell ◽  
Theory Series

Hexagonal grid methods are found useful in many research works, including numerical modeling in spherical coordinates, in atmospheric and ocean models, and simulation of electrical wave phenomena in cardiac tissues. Almost all of these used standard Laplacian and mostly on one configuration of regular hexagons. In this work, discrete symmetric boundary condition and energy product for anisotropic Laplacian are investigated firstly on general net of regular hexagons, and then generalized to its most extent in two- or three-dimensional cell-center finite difference applications up to the usage of symmetric stencil in central differences. For analysis of Laplacian related applications, this provides with an approach in addition to the M-matrix theory, series method, functional interpolations and Fourier vectors.

Two- and three-dimensional locomotion of the nematode Nippostrongylus brasiliensis

Parasitology ◽  
1990 ◽  
Vol 101 (2) ◽  
pp. 301-308 ◽  
Author(s):  
D. L. Lee ◽  
W. D. Biggs
Keyword(s):  
Sodium Alginate ◽  
Intestinal Mucosa ◽  
Three Dimensional ◽  
Viscous Medium ◽  
Nippostrongylus Brasiliensis ◽  
Two Dimensional ◽  
Immune Rejection ◽  
Forward Movement ◽  
Helical Wave ◽  
Dimensional Wave

Locomotion of adult Nippostrongylus brasiliensis has been studied in saline, in 0.6% agar, in sodium alginate of different viscosities and amongst sand grains in these media. In saline the nematode formed two-dimensional waves but there was little forward progression. Amongst sand grains in saline the nematode moved forwards by thrusting against sand grains, but thigmokinetic behaviour later resulted in quiescence. In 0.6% agar and in alginates of weak viscosity the nematode produced two-dimensional waves and sometimes a three-dimensional helical wave which resulted in forward movement. The formation of three-dimensional waves and the distance travelled increased with increasing viscosity up to 4% sodium alginate and also amongst sand gains in these media. In 8% sodium alginate the nematode became coiled like a spring but remained almost stationary. The three-dimensional wave is formed with torsion and obtains thrust from the viscous medium. In the intestine of the host thrust will be obtained from the mucus and villi of the intestinal mucosa. The ability of this nematode to move by two-and three-dimensional undulatory propulsion is probably related to its complex ridged cuticle. Attention is drawn to the role that increased viscosity of mucus may play in entrapping nematodes during their immune rejection.

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