Tsunami wave propagation by voronoi diagram

Cellular automata is the model applied in very complicated situations and complex problems. It involves the Introduction of voronoi diagram in tsunami wave propagation with the help of a fast-marching method to find the spread of the tsunami waves in the coastal regions. In this study we have modelled and predicted the tsunami wave propagation using the finite difference method. This analytical method gives the horizontal and vertical layers of the wave run up and enables the calculation of reaching time.

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BOAT-SAIL VORONOI DIAGRAM AND ITS APPLICATION

International Journal of Computational Geometry & Applications ◽

10.1142/s0218195909003052 ◽

2009 ◽

Vol 19 (05) ◽

pp. 425-440 ◽

Cited By ~ 2

Author(s):

TETSUSHI NISHIDA ◽

KOKICHI SUGIHARA

Keyword(s):

Differential Equation ◽

Partial Differential Equation ◽

Boundary Value Problem ◽

Voronoi Diagram ◽

Water Surface ◽

Eikonal Equation ◽

Fast Marching Method ◽

Fast Marching ◽

Marching Method ◽

Generalized Voronoi Diagram

A new generalized Voronoi diagram, called a boat-sail Voronoi diagram, is defined on the basis of the time necessary for a boat to reach on water surface with flow. A new concept called a boat-sail distance is introduced on the surface of water with flow, and it is used to define a generalized Voronoi diagram, in such a way that the water surface is partitioned into regions belonging to the nearest harbors with respect to this distance. The problem of computing this Voronoi diagram is reduced to a boundary value problem of a partial differential equation, and a numerical method for solving this problem is constructed. The method is a modification of a so-called fast marching method originally proposed for the eikonal equation. Computational experiments show the efficiency and the stableness of the proposal method. We also apply our equation to the shortest path problem and the simulation of the forest fire.

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Numerical Investigations of Tsunami Run-Up and Flow Structure on Coastal Vegetated Beaches

Water ◽

10.3390/w10121776 ◽

2018 ◽

Vol 10 (12) ◽

pp. 1776 ◽

Cited By ~ 2

Author(s):

Hongxing Zhang ◽

Mingliang Zhang ◽

Tianping Xu ◽

Jun Tang

Keyword(s):

Wave Propagation ◽

Numerical Model ◽

Peak Flow ◽

Tsunami Wave ◽

Coastal Vegetation ◽

Coastal Forest ◽

Governing Equations ◽

Tsunami Waves ◽

Run Up ◽

Sloping Beach

Tsunami waves become hazardous when they reach the coast. In South and Southeast Asian countries, coastal forest is widely utilized as a natural approach to mitigate tsunami damage. In this study, a depth-integrated numerical model was established to simulate wave propagation in a coastal region with and without forest cover. This numerical model was based on a finite volume Roe-type scheme, and was developed to solve the governing equations with the option of treating either a wet or dry wave front boundary. The governing equations were modified by adding a drag force term caused by vegetation. First, the model was validated for the case of solitary wave (breaking and non-breaking) run-up and run-down on a sloping beach, and long periodic wave propagation was investigated on a partially vegetated beach. The simulated results agree well with the measured data. Further, tsunami wave propagation on an actual-scale slope covered by coastal forest Pandanus odoratissimus (P. odoratissimus) and Casuarina equisetifolia (C. equisetifolia) was simulated to elucidate the influence of vegetation on tsunami mitigation with a different forest open gap. The numerical results revealed that coastal vegetation on sloping beach has significant potential to mitigate the impacts from tsunami waves by acting as a buffer zone. Coastal vegetation with open gaps causes the peak flow velocity at the exit of the gap to increase, and reduces the peak flow velocity behind the forest. Compared to a forest with open gaps in a linear arrangement, specific arrangements of gaps in the forest can increase the energy attenuation from tsunami wave. The results also showed that different cost-effective natural strategies in varying forest parameters including vegetation collocations, densities, and growth stages had significant impacts in reducing the severity of tsunami damage.

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Mobile Robot Path Planning using Voronoi Diagram and Fast Marching

Robotics, Automation, and Control in Industrial and Service Settings - Advances in Civil and Industrial Engineering ◽

10.4018/978-1-4666-8693-9.ch003 ◽

2015 ◽

pp. 92-108 ◽

Cited By ~ 1

Author(s):

S. Garrido ◽

L. Moreno

Keyword(s):

Path Planning ◽

Mobile Robot ◽

Voronoi Diagram ◽

High Speed ◽

Fast Marching Method ◽

Robot Path Planning ◽

Fast Marching ◽

Path Planner ◽

Marching Method ◽

Robot Path

This chapter presents a new sensor-based path planner, which gives a fast local or global motion plan capable to incorporate new obstacles data. Within the first step, the safest areas in the environment are extracted by means of a Voronoi Diagram. Within the second step, the fast marching method is applied to the Voronoi extracted areas so as to get the trail. This strategy combines map-based and sensor-based designing operations to supply a reliable motion plan, whereas it operates at the frequency of the sensor. The most interesting characteristics are high speed and reliability, as the map dimensions are reduced to a virtually one-dimensional map and this map represents the safest areas within the environment.

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Estimates of Amplitude Characteristics of Tsunami Wave Run-Up in Various Areas of the Black Sea Coast

Ekologicheskaya bezopasnost pribrezhnoy i shel fovoy zon morya ◽

10.22449/2413-5577-2021-1-34-46 ◽

2021 ◽

Author(s):

A. Yu. Belokon ◽

Keyword(s):

Wave Propagation ◽

Sea Level ◽

Black Sea ◽

Tsunami Wave ◽

Computational Modelling ◽

Wave Model ◽

The Black Sea ◽

Tsunami Propagation ◽

Tsunami Waves ◽

Run Up

This paper is devoted to computational modelling of tsunami wave propagation and runup to the shore for some points on the Russian, Turkish, Bulgarian and Ukrainian coasts of the Black Sea. The nonlinear long wave model was used to solve the problem of wave propagation from hydrodynamic tsunami sources, which can constitute the greatest potential danger for the studied coast areas. The hydrodynamic sources were set in the form of an elliptical elevation, the parameters of which were chosen according to the sea level response to an underwater earthquake of magnitude 7. All the sources were located in seismically active areas, where tsunamigenic earthquakes had already occurred, along the 1500 m isobath. Near each of the studied points in the area above 300 m depths, we calculated marigrams, i.e. time-series of sea level fluctuations caused by the passage of waves. Then, a one-dimensional problem of tsunami propagation and run-up on the coast was solved for each of the points under study, where the obtained marigrams were used as boundary conditions. Peculiarities of tsunami wave propagation have been shown depending on the bottom and land relief in the studied areas of the Black Sea. Estimates have been obtained of the sea level maximum rise and fall during surge and subsequent coastal drainage for the characteristic scales of relief irregularity at different points. For possible tsunamigenic earthquakes, the largest splashes may occur in the region of Yalta (2.15 m), Cide (1.9 m), Sevastopol (1.4 m), and Anapa (1.4 m). Tsunami propagation in the Feodosiya and Varna coastal areas is qualitatively similar, with maximum wave heights of 0.64 m and 0.46 m, respectively. The coastlines of Evpatoriya (0.33 m) and Odessa (0.26 m) are least affected by tsunami waves due to the extended shelf.

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Fast Marching Method Aplication for Forward Modelling of Seismic Wave Propagation

Jurnal Geofisika ◽

10.36435/jgf.v16i3.107 ◽

2018 ◽

Vol 16 (3) ◽

pp. 1

Author(s):

Wahyu Srigutomo ◽

Ghany Hanifan Muslim

Keyword(s):

Wave Propagation ◽

Viscosity Solution ◽

Seismic Wave ◽

Eikonal Equation ◽

Heterogeneous Media ◽

Seismic Wave Propagation ◽

Time Travel ◽

Fast Marching Method ◽

Fast Marching ◽

Marching Method

One of the classical problem in seismology is to determine time travel and ray path of seismic wave betweentwo points at a given heterogeneous media. This problem is expressed by eikonal equation and can be seen as a propagation of a wavefront and interface evolution. One of methods to solve this problem is Fast Marching Method abbreviated as FMM. This method is used to produce entropy-satisfying viscosity solution of eikonal equation. FMM combines viscosity solution of Hamilton-Jacobi equation and Huygen's Principle that centered on min-heap data structure to determine the minimum value at every loop. In this study, FMM is applied to determine time travel and raypath of seismic wave. FMM also is used to determine the location of wavesource using simple algorithm. From our forward modeling schemes, it is found that FMM is an accurate, robust, and effcient method to simulate seismic wave propagation. For further study, FMM also can be used to be a part of passive seismic inverse scheme to locate hypocenter location.

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