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Firefighting on square, hexagonal, and triangular grids [article]

Tomas Gavenciak, Jan Kratochvil, Pawel Pralat
2014 arXiv   pre-print
For the infinite hexagonal grid we provide a winning strategy if two additional vertices can be protected at any point of the process, and we conjecture that the firefighter has no strategy to stop the  ...  In each subsequent time unit, a firefighter protects one vertex which is not yet on fire, and then the fire spreads to all unprotected neighbors of the vertices on fire.  ...  Note that this is the case for square, hexagonal, triangular and many other grid-like graphs. Proof. Assume fixed c, c , F and S and let d = d(c , c).  ... 
arXiv:1305.7076v2 fatcat:qfr5gsnbjrexbo4tuqe4w5gaga

Survey of deployment algorithms in wireless sensor networks: coverage and connectivity issues and challenges

Saoucene Mahfoudh, Pascale Minet, Anis Laouiti, Ines Khoufi
2017 International Journal of Autonomous and Adaptive Communications Systems  
We present a survey that focuses on two major issues in WSNs: coverage and connectivity.  ...  Monitoring a given zone is one of the main goals of this technology.  ...  This pattern can be a triangular lattice, a square grid, an hexagonal grid or a rhomboid grid.  ... 
doi:10.1504/ijaacs.2017.10009671 fatcat:wljdtd3iabeobniv2qwm35il4a

The Coarse Geometry of Hartnell's Firefighter Problem on Infinite Graphs [article]

Danny Dyer and Eduardo Martinez-Pedroza and Brandon Thorne
2017 arXiv   pre-print
In particular, we positively answer a conjecture by Develin and Hartke by proving that the $d$-dimensional square grid $\mathbb{L}^d$ does not satisfy the $cn^{d-3}$-containment property for any constant  ...  In this article, we study Hartnell's Firefighter Problem through the group theoretic notions of growth and quasi-isometry.  ...  We thank Bojan Mohar for comments on a preliminary version of the article, in particular, for pointing out Corollary 2.4 and suggesting Question 2.5.  ... 
arXiv:1507.03050v6 fatcat:q2ocouqhxfhdlphzwr2sh4my4u

Applying Cell-DEVS Methodology for Modeling the Environment

Gabriel Wainer
2006 Simulation (San Diego, Calif.)  
The results can be used to determine the best place for firefighters in terms of safety and efficiency.  ...  We present the definition of different models of environmental applications, including the pollution on a basin, fire spreading, watershed formation and viability of a population, focusing on how to define  ...  Although triangular and hexagonal meshes provide better results in terms of the area covered, most researchers still use square lattices, as most GIS sys-tems and existing modeling tools are based on square  ... 
doi:10.1177/0037549706073698 fatcat:gpd6725az5a6xbwn464xkgatk4

Firefighting as a Strategic Game

Carme Álvarez, Maria J. Blesa, Hendrik Molter
2015 Internet Mathematics  
Most research on the problem considers the case in which the fire starts in a single place (i.e., f = 1), and in which the budget of available firefighters per time-step is one (i.e., b = 1).  ...  The Firefighter Problem was proposed in 1995 as a deterministic discrete-time model for the spread and containment of a fire.  ...  There exist concrete results for triangular, strong, and hexagonal grids [20, 31, 32, 33, 22] , and for other graph classes [21] .  ... 
doi:10.1080/15427951.2015.1110542 fatcat:tqygmwr4zfarfjipj6wvbgrgoq

Supplemental Material for The Development of Haptic Processing Skills From Childhood to Adulthood by Means of Two-Dimensional Materials

2017 Canadian journal of experimental psychology  
, hexagon, isosceles triangle, trapezoid and cross).  ...  -Texture: the stimuli used were raised-line squares filled with different textures (small crosses such as +, grid lines, grid points, horizontal lines, vertical lines, thick oblique lines, small horizontal  ...  can hold in your hand" for the comb and scissors, "this is an object used by firefighters" for the ladder, "this is an item of clothing" for the sweater, "this is a musical instrument" for the guitar  ... 
doi:10.1037/cep0000121.supp fatcat:vadtzshldbbglby4r7efwtgdhi

Control of spatio-temporal pattern formation governed by geometrical models of interface evolution

Adrian Bouaru, Daniel Coca
2014 2014 European Control Conference (ECC)  
In particular, the focus is set on the control of dendritic crystal growth and wind aided wildfire spread.  ...  Using a level set formulation of the evolving interface, a cost function is derived that allows the selection of a spatial location, such that the firefighting action has the best results with respect  ...  The most common lattice structure is the square lattice, mainly due to its relatively simple numerical implementation, but hexagonal and triangular lattice structures have been used in literature (Morita  ... 
doi:10.1109/ecc.2014.6862521 fatcat:t6betidyrrgtzf7adhapbwpk6i

Vision-Controlled Micro Flying Robots: From System Design to Autonomous Navigation and Mapping in GPS-Denied Environments

Davide Scaramuzza, Michael C. Achtelik, Lefteris Doitsidis, Fraundorfer Friedrich, Elias Kosmatopoulos, Agostino Martinelli, Markus W. Achtelik, Margarita Chli, Savvas Chatzichristofis, Laurent Kneip, Daniel Gurdan, Lionel Heng (+10 others)
2014 IEEE robotics & automation magazine  
The hexagon-shaped six-rotor design was chosen as the best tradeoff.  ...  Out of the 3-D occupancy grid, a height map was generated ( Figure 19 ) and fed to the CAO algorithm to compute the optimal-coverage poses.  ... 
doi:10.1109/mra.2014.2322295 fatcat:mpqjh7stxjdhvcelub5f2kcpym

PROPAGATOR: An Operational Cellular-Automata Based Wildfire Simulator

Andrea Trucchia, Mirko D'Andrea, Francesco Baghino, Paolo Fiorucci, Luca Ferraris, Dario Negro, Andrea Gollini, Massimiliano Severino
2020 Fire  
The fire spread probability depends on vegetation type, slope, wind direction and speed, and fuel moisture content.  ...  PROPAGATOR simulates independent realizations of one stochastic fire propagation process, and at each time-step gives as output a map representing the probability of each cell of the domain to be affected  ...  CA models for wildfire simulation model discretize spatial interactions by adopting a square or hexagonal [26] grid.  ... 
doi:10.3390/fire3030026 fatcat:curvixy7lbecdbgdsjof72edpi

The development of haptic processing skills from childhood to adulthood by means of two-dimensional materials

Anaïs Mazella, Jean-Michel Albaret, Delphine Picard
2018 Canadian journal of experimental psychology  
Ninety-one participants, aged 4 years to adult, were asked to perform a series of haptic tasks that entailed (1) finding dots and following lines, (2) matching elements based on texture, shape, and size  ...  , (3) matching elements based on spatial location and orientation, (4) memorizing sequences of dots and shapes and (5) identifying complete and incomplete raised-line pictures.  ...  , hexagon, isosceles triangle, trapezoid and cross).  ... 
doi:10.1037/cep0000121 pmid:28394168 fatcat:gghdfp4l6felhejsljns6cxpym


P Praiwattana
While the training in physical workouts give crisis personal a hand-on experience in the given situation, it often requires a long time to prepare with a considerable budget.  ...  A crisis is an infrequent and unpredictable event. Training and preparation process requires tools for representation of crisis context.  ...  Both thanks toward family and friends for their supports are invaluable during a hardship and stress. v  ... 
doi:10.24377/ fatcat:f4lki2bdfnao3k24yv73rqh5mi

Wideband and UWB Antennas for Wireless Applications: A Comprehensive Review

Renato Cicchetti, Emanuela Miozzi, Orlandino Testa
2017 International Journal of Antennas and Propagation  
Planar, printed, dielectric, and wearable antennas, achievable on laminate (rigid and flexible), and textile dielectric substrates are taken into account.  ...  A comprehensive review concerning the geometry, the manufacturing technologies, the materials, and the numerical techniques, adopted for the analysis and design of wideband and ultrawideband (UWB) antennas  ...  To this purpose, several slots geometries, such as square, rectangular, triangular, circular, and elliptical together with suitable excitation techniques making use of cross, fork, triangle, square, and  ... 
doi:10.1155/2017/2390808 fatcat:6766lx67jbhehmpfece7r4urki

Centralized Collision-free Polynomial Trajectories and Goal Assignment for Aerial Swarms [article]

Benjamin Gravell, Tyler Summers
2021 arXiv   pre-print
The method first assigns robots to goals to minimize total time-in-motion based on initial trajectories.  ...  By coupling the assignment and trajectory generation, the initial motion plans tend to require only limited collision resolution.  ...  Experiment description and findings One experiment ("X20") is now presented with = 20 agents moving in a 2m by 3m room from start locations randomly selected from a grid with 0.5m spacing to goals arranged  ... 
arXiv:2101.08829v1 fatcat:w2lnau5z3vdbrnnco5inetf5lq

Spatiotemporal enabled Content-based Image Retrieval

Mariana Belgiu, Martin Sudmanns, Tiede Dirk, Andrea Baraldi, Stefan Lang
2016 International Conference on GIScience Short Paper Proceedings  
A sensor in WSNs covers only a limited region, depending on its sensing and communicating ranges, as well as the environment configuration.  ...  and natural obstacles in the sensing areas (Wang and Cao 2011).  ...  Demšar who read and commented on an earlier version.  ... 
doi:10.21433/b311729295dw fatcat:fulw4pw3kfh5nmfzcsy3pkisvm

Biomimicry in textiles: past, present and potential. An overview

L. Eadie, T. K. Ghosh
2011 Journal of the Royal Society Interface  
Biomimetic research is a rapidly growing field and its true potential in the development of new and sustainable textiles can only be realized through interdisciplinary research rooted in a holistic understanding  ...  Throughout the millennia, nature has evolved to adapt and develop highly sophisticated methods to solve problems.  ...  Cannon Professor, Emeritus, North Carolina State University, Raleigh, USA, for his critical reading of the manuscript and many valuable suggestions.  ... 
doi:10.1098/rsif.2010.0487 pmid:21325320 pmcid:PMC3104345 fatcat:vzvakqkyerd6tpzv3wsqygpaku
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