Page 26 - Fister jr., Iztok, Andrej Brodnik, Matjaž Krnc and Iztok Fister (eds.). StuCoSReC. Proceedings of the 2019 6th Student Computer Science Research Conference. Koper: University of Primorska Press, 2019
P. 26
le 1: Results for the comparison of the solutions in changes of the cost, as well as in the changes in the
locations for both the Italian and German networks.
tance between the old and the new location of the facilities 6. ACKNOWLEDGMENTS
was 81.6 on average (minimum 0, maximum 247). Even
with a 40% loss of the edges the distance was 188.35 on av- This research was supported by the European Union and
erage (minimum 178, maximum 264). When we located 2 co-financed by the European Social Fund (EFOP-3.6.3-
medians, the average change was around 40 (minimum 0, VEKOP-16-2017-00002).
maximum 195) with deleting 10% of the edges and 105,2
(minimum 0, maximum 276) with a 40% loss. With the 3- 7. REFERENCES
median problem, the minimal change was about 70 and the
maximal change was about 132. [1] O. Berman, D. Krass, and M. B. C. Menezes. Facility
reliability issues in network p-median problems:
5. CONCLUSION AND FUTURE PLANS Strategic centralization and co-location effects.
Operations Research, 55(2):332–350, 2007.
By the results we can see that the change of the solution
during deleting edges highly depends on the shape of the [2] M. S. Daskin. Network and Discrete Location: Models,
graph we work with. If the graph has just a few connections Algorithms and Applications. John Wiley and Sons,
between two main parts, deleting of the edges can cause New York, 1995.
very high costs. If we work with a well-balanced graph,
even by deleting 40% of the edges the solution changes just [3] S. L. Hakimi. Optimum locations of switching centers
a little. We also could see that the location of the facilities and the absolute centers and medians of a graph.
do not change too much. In the future we are planning Operations Research, 12(3):450–459, 1964.
to inspect how a non-oriented weighted graph reacts to p-
median problem when we change the weights of edges, like [4] X. Zhao, K. Carling, Z. Dan, and J. HA˜ˇekansson.
when traffic changes or when we add new edges. We also Network density and the p-median solution. Technical
would like to check if we can make clusters according to how report, Ho¨gskolan Dalarna, Borla¨nge, 2013.
likely that a facility is located in a vertex. Furthermore we
want to inspect how a non-oriented weighted graph reacts
to other problems such as p-center problem during similar
conditions.
StuCoSReC Proceedings of the 2019 6th Student Computer Science Research Conference 26
Koper, Slovenia, 10 October
locations for both the Italian and German networks.
tance between the old and the new location of the facilities 6. ACKNOWLEDGMENTS
was 81.6 on average (minimum 0, maximum 247). Even
with a 40% loss of the edges the distance was 188.35 on av- This research was supported by the European Union and
erage (minimum 178, maximum 264). When we located 2 co-financed by the European Social Fund (EFOP-3.6.3-
medians, the average change was around 40 (minimum 0, VEKOP-16-2017-00002).
maximum 195) with deleting 10% of the edges and 105,2
(minimum 0, maximum 276) with a 40% loss. With the 3- 7. REFERENCES
median problem, the minimal change was about 70 and the
maximal change was about 132. [1] O. Berman, D. Krass, and M. B. C. Menezes. Facility
reliability issues in network p-median problems:
5. CONCLUSION AND FUTURE PLANS Strategic centralization and co-location effects.
Operations Research, 55(2):332–350, 2007.
By the results we can see that the change of the solution
during deleting edges highly depends on the shape of the [2] M. S. Daskin. Network and Discrete Location: Models,
graph we work with. If the graph has just a few connections Algorithms and Applications. John Wiley and Sons,
between two main parts, deleting of the edges can cause New York, 1995.
very high costs. If we work with a well-balanced graph,
even by deleting 40% of the edges the solution changes just [3] S. L. Hakimi. Optimum locations of switching centers
a little. We also could see that the location of the facilities and the absolute centers and medians of a graph.
do not change too much. In the future we are planning Operations Research, 12(3):450–459, 1964.
to inspect how a non-oriented weighted graph reacts to p-
median problem when we change the weights of edges, like [4] X. Zhao, K. Carling, Z. Dan, and J. HA˜ˇekansson.
when traffic changes or when we add new edges. We also Network density and the p-median solution. Technical
would like to check if we can make clusters according to how report, Ho¨gskolan Dalarna, Borla¨nge, 2013.
likely that a facility is located in a vertex. Furthermore we
want to inspect how a non-oriented weighted graph reacts
to other problems such as p-center problem during similar
conditions.
StuCoSReC Proceedings of the 2019 6th Student Computer Science Research Conference 26
Koper, Slovenia, 10 October
