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Median problems with positive and negative weights on cycles and cacti

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Abstract

This paper deals with facility location problems on graphs with positive and negative vertex weights. We consider two different objective functions: In the first one (MWD) vertices with positive weight are assigned to the closest facility, whereas vertices with negative weight are assigned to the farthest facility. In the second one (WMD) all the vertices are assigned to the nearest facility. For the MWD model it is shown that there exists a finite set of points in the graph which contains the locations of facilities in an optimal solution. Furthermore, algorithms for both models for the 2-median problem on a cycle are developed. The algorithm for the MWD model runs in linear time, whereas the algorithm for the WMD model has a time complexity of  \(\mathcal{O}(n^{2})\) .

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References

  • Benkoczi R (2004) Cardinality constrained facility location problems in trees. PhD thesis, Simon Fraser University

  • Benkoczi R, Breton D, Bhattacharya B (2006) Efficient computation of 2-medians in a tree network with positive/negative weights. Discrete Math 306:1505–1516

    Article  MATH  MathSciNet  Google Scholar 

  • Burkard R, Çela E, Dollani H (2000) 2-medians in trees with pos/neg weights. Discrete Appl Math 105: 51–71

    Article  MATH  MathSciNet  Google Scholar 

  • Burkard R, Fathali J (2007) A polynomial time method for the pos/neg weighted 3-median problem on a tree. Math Methods Oper Res 65:229–238

    Article  MATH  MathSciNet  Google Scholar 

  • Burkard R, Krarup J (1998) A linear algorithm for the pos/neg-weighted 1-median problem on a cactus. Computing 60:193–215

    Article  MATH  MathSciNet  Google Scholar 

  • Burkard R, Fathali J, Taghizadeh H (2007) The p-maxian problem on a tree. Oper Res Lett 35:331–335

    Article  MATH  MathSciNet  Google Scholar 

  • Church R, Garfinkel R (1978) Locating an obnoxious facility on a network. Transp Sci 12:107–118

    Article  MathSciNet  Google Scholar 

  • Garey MR, Johnson DS (1979) Computers and intractability: a guide to the theory of NP-completeness. Freeman, New York

    MATH  Google Scholar 

  • Gavish B, Sridhar S (1995) Computing the 2-median on tree networks in \(\mathcal{O}(n\log n)\) time. Networks 26:305–317

    Article  MATH  MathSciNet  Google Scholar 

  • Goldman A (1971) Optimal center location in simple networks. Transp Sci 5:212–221

    Article  Google Scholar 

  • Hakimi S (1964) Optimal locations of switching centers and the absolute centers and medians of a graph. Oper Res 12:450–459

    Article  MATH  Google Scholar 

  • Handler G (1973) Minimax location of a facility in an undirected tree graph. Transp Sci 7:287–293

    Article  MathSciNet  Google Scholar 

  • Hua L (1962) Applications of mathematical methods for wheat harvesting. Chin Math 2:77–91

    Google Scholar 

  • Kariv O, Hakimi S (1979) An algorithmic approach to network location problems, Part II: p-medians. SIAM J Appl Math 27:539–560

    Article  MathSciNet  Google Scholar 

  • Mirchandani P (1990) The p-median problem and generalizations. In: Mirchandani P, Francis R (eds) Discrete location theory. Wiley, New York, pp 55–117

    Google Scholar 

  • Tamir A (1996) An \(\mathcal{O}(pn^{2})\) algorithm for the p-median and related problems on tree graphs. Oper Res Lett 19:59–64

    Article  MATH  MathSciNet  Google Scholar 

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Correspondence to Rainer E. Burkard.

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Burkard, R.E., Hatzl, J. Median problems with positive and negative weights on cycles and cacti. J Comb Optim 20, 27–46 (2010). https://doi.org/10.1007/s10878-008-9187-4

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  • DOI: https://doi.org/10.1007/s10878-008-9187-4

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