Authors:
            
                    Marc Demange
                    
                        
                    
                     and
                
                    Cerasela Tanasescu
                    
                        
                    
                    
                
        
        
            Affiliation:
            
                    
                        
                    
                    RMIT University, Australia
                
        
        
        
        
        
             Keyword(s):
            Multi-period Vertex Cover, Wildfire, Fuel Management, Planar Graphs, Polynomial Approximation, Approximation Preserving Reductions.
        
        
            
                Related
                    Ontology
                    Subjects/Areas/Topics:
                
                        Applications
                    ; 
                        Artificial Intelligence
                    ; 
                        Energy and Environment
                    ; 
                        Knowledge Discovery and Information Retrieval
                    ; 
                        Knowledge-Based Systems
                    ; 
                        Mathematical Modeling
                    ; 
                        Methodologies and Technologies
                    ; 
                        Operational Research
                    ; 
                        Optimization
                    ; 
                        Pattern Recognition
                    ; 
                        Software Engineering
                    ; 
                        Symbolic Systems
                    
            
        
        
            
                Abstract: 
                We consider a generalisation of MIN WEIGHTED VERTEX COVER motivated by a problem in wildfire prevention. The problem is defined for a fixed number of time periods and we have to choose, at each period, some vertices to be deleted such that we never have two adjacent remaining vertices. The specificity is that whenever a vertex is deleted it reappears after a given number of periods. Consequently we may need to delete a single vertex several times. The objective is to minimise the total weight (cost) of deleted vertices. The considered application motivates the case of planar graphs. While similar problems have been mainly solved using mixed integer linear models (MIP) we investigate a graph approach that allows to take into account the structure of the underlying graph. We use a reduction to the usual MIN WEIGHTED VERTEX COVER to devise efficient approximation algorithms and to raise some polynomial classes.